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  1. Teknik Perangkingan Meta-search Engine

    OpenAIRE

    Puspitaningrum, Diyah

    2014-01-01

    Meta-search engine mengorganisasikan penyatuan hasil dari berbagai search engine dengan tujuan untuk meningkatkan presisi hasil pencarian dokumen web. Pada survei teknik perangkingan meta-search engine ini akan didiskusikan isu-isu pra-pemrosesan, rangking, dan berbagai teknik penggabungan hasil pencarian dari search engine yang berbeda-beda (multi-kombinasi). Isu-isu implementasi penggabungan 2 search engine dan 3 search engine juga menjadi sorotan. Pada makalah ini juga dibahas arahan penel...

  2. Analisis Teknik-Teknik Keamanan Pada Future Cloud Computing vs Current Cloud Computing: Survey Paper

    Directory of Open Access Journals (Sweden)

    Beny Nugraha

    2016-08-01

    Full Text Available Cloud computing adalah salah satu dari teknologi jaringan yang sedang berkembang pesat saat ini, hal ini dikarenakan cloud computing memiliki kelebihan dapat meningkatkan fleksibilitas dan kapabilitas dari proses komputer secara dinamis tanpa perlu mengeluarkan dana besar untuk membuat infrastruktur baru, oleh karena itu, peningkatan kualitas keamanan jaringan cloud computing sangat diperlukan. Penelitian ini akan meneliti teknik-teknik keamanan yang ada pada cloud computing saat ini dan arsitektur cloud computing masa depan, yaitu NEBULA. Teknik-teknik keamanan tersebut akan dibandingkan dalam hal kemampuannya dalam menangani serangan-serangan keamanan yang mungkin terjadi pada cloud computing. Metode yang digunakan pada penelitian ini adalah metode attack centric, yaitu setiap serangan keamanan dianalisis karakteristiknya dan kemudian diteliti mekanisme keamanan untuk menanganinya. Terdapat empat serangan keamanan yang diteliti dalam penelitian ini, dengan mengetahui bagaimana cara kerja sebuah serangan keamanan, maka akan diketahui juga mekanisme keamanan yang mana yang bisa mengatasi serangan tersebut. Dari penelitian ini didapatkan bahwa NEBULA memiliki tingkat keamanan yang paling tinggi. NEBULA memiliki tiga teknik baru yaitu Proof of Consent (PoC, Proof of Path (PoP, dan teknik kriptografi ICING. Ketiga teknik tersebut ditambah dengan teknik onion routing dapat mengatasi serangan keamanan yang dianalisa pada penelitian ini.

  3. CRISPR – hot genteknologisk teknik til at skabe nye sygdomsmodeller

    DEFF Research Database (Denmark)

    Alstrup, Aage Kristian Olsen

    2017-01-01

    CRISPR er i en ny genteknologisk teknik, som gør det muligt at ændre i genomet på alle arter af forsøgsdyr, hvor den gammelkendte teknik kun fungerede i mus.......CRISPR er i en ny genteknologisk teknik, som gør det muligt at ændre i genomet på alle arter af forsøgsdyr, hvor den gammelkendte teknik kun fungerede i mus....

  4. PERBEDAAN MODALITAS VISUAL, AUDITORIAL DAN KINESTETIK SISWA KELAS X SMK JURUSAN TEKNIK PERMESINAN DAN TEKNIK KENDARAAN RINGAN

    Directory of Open Access Journals (Sweden)

    Margaretha F. Dian Pratiwi

    2015-06-01

    Full Text Available Penelitian ini bertujuan untuk mengetahui signifikansi perbedaan modalitas siswa antar Jurusan Teknik Mesin dan Teknik Kendaraan Ringan kelas X SMK Muhammadiyah Salatiga. Subjek penelitian ini adalah seluruh siswa kelas X Jurusan Teknik Mesin dan seluruh siswa Teknik Kendaraan Ringan SMK Muhammadiyah Salatiga. Instrumen yang digunakan adalah kuesioner modalitas belajar. Adapun teknik analisis data menggunakan Chi Square yang diolah dengan program SPSS 16.0 for Windows. Analisis komparatif dengan menggunakan Chi-Square didapat value 9,384 dengan nilai signifikansi 0,009 < 0,01. Dengan demikian, hasil analisis menunjukkan terdapat perbedaan yang sangat signifikan antara modalitas visual, auditorial, kinestetik siswa kelas X Teknik Permesinan dan Teknik Kendaraan Ringan di SMK Muhammadiyah Salatiga.

  5. Problematika Penyelesaian Proyek Akhir bagi Mahasiswa Program Diploma 3 Jurusan Teknik Otomotif Fakultas Teknik UNY

    Directory of Open Access Journals (Sweden)

    Tawardjono Tawardjono

    2010-05-01

    Full Text Available Penelitian ini bertujuan menemukan kesulitan-kesulitan mahasiswa dalam menyelesaikan proyek akhir (PA, yang meliputi: menentukan judul/topik, proses bimbingan, prosespengerjaan, menulis laporan, serta menemukan solusi permasalahannya.Penelitian ini termasuk penelitian deskriptif kualitatif. Populasi penelitian adalah mahasiswa yang telah dan sedang mengerjakan Proyek Akhir pada tahun perkuliahan 2009/2010 dan Dosen Pembimbing PA jurusan Teknik Otomotif. Teknik sampling menggunakan ’incidental sampling’ yang didapat 55 mahasiswa dan 15 dosen pembimbing. Teknik pengambilan data menggunakan kuesioner dan wawancara sebagai pelengkap. Teknik analisis data menggunakan analisis deskriptif kualitatif.Hasil penelitian menunjukkan bahwa: Kesulitan terbesar mahasiswa datang dari faktor internal, khususnya kejiwaan mereka yang meliputi aspek motivasi dan tanggung jawab mahasiswa menyelesaikan proyek akhir. Hambatan berikutnya berturut-turut: faktor instrumental, lingkungan dan kejasmanian; Hambatan mahasiswa dalam pelaksanaan Proyek Akhir adalah dalam menentukan judul, melakukan perhitungan dan pembuktian dan masalah plagiat. Solusi yang disampaikan adalah mahasiswa perlu memilih dan menentukan judul yang feasibel, menambah wawasan pengetahuan teknik dan aplikasi otomotif, melatih kreativitas dan inovasi, memperdalam materi metodologi dan proaktif terhadap kegiatan bimbingan, membuat jadwal penggunaan bengkel dan dosen pembimbing di bengkel.

  6. Perancangan dan Implementasi Sistem Informasi Perpustakaan di Program Studi Teknik Lingkungan Fakultas Teknik Undip

    Directory of Open Access Journals (Sweden)

    Lia Dorothy

    2014-11-01

    Full Text Available Perkembangan teknologi informasi menciptakan keunggulan kompetitif dalam berbagai bidang. Perkembangan ini didukung oleh industri perangkat keras dan perangkat lunak komputer yang terus berkembang, yakni dengan pengaksesan dan pemrosesan informasi yang cepat, akurat, dan efisien melalui sebuah sistem informasi. Pengelolaan data buku di perpustakaan Teknik Lingkungan masih dilakukan menggunakan microsoft office excel, sedangkan pengelolaan data anggota dan data peminjaman masih dicatat secara manual. Oleh karena itu, diperlukan sebuah penelitian untuk membangun sebuah sistem informasi perpustakaan yang dapat mempermudah pengelolaan data dan aktivitas perpustakaan di Program Studi Teknik Lingkungan. Sistem informasi perpustakaan terkomputerisasi ini diharapkan dapat membantu pengelolaan data buku dan data anggota, transaksi peminjaman dan pengembalian buku, serta menghasilkan laporan untuk keperluan administrasi perpustakaan, sehingga dapat meningkatkan efektifitas kinerja karyawan. Sistem informasi perpustakaan ini berbasis web, dikembangkan dengan bahasa pemrograman PHP dan basis data MySQL, serta menggunakan framework CodeIgniter. Sistem informasi ini juga dilengkapi dengan barcode reader yang digunakan untuk mempermudah pengelolaan data buku. Penelitian dikembangkan dengan metode SDLC (System Development Life Cycle. Langkah-langkah penelitian meliputi tahap perencanaan, tahap analisis, tahap perancangaan, tahap implementasi, tahap pengujian, dan tahap pemeliharaan. Sistem dirancang dengan menggunakan diagram UML (Unified Modelling Language dan diuji dengan pengujian kotak hitam (blackbox testing. Semua menu dalam sistem informasi perpustakaan dan barcode reader dapat bekerja dengan baik. Sistem informasi perpustakaan telah diimplementasikan di Program Studi Teknik Lingkungan Fakultas Teknik UNDIP. Sistem informasi ini menambah kualitas pelayanan pada perpustakaan Teknik Lingkungan.

  7. Eksplorasi Pewarnaan Teknik Smock Kombinasi Tritik Jumputan untuk Produk Fashion

    OpenAIRE

    Suryawati Ristiani; Irianti Nugrahani

    2016-01-01

    ABSTRAKKain tritik jumputan merupakan salah satu jenis kerajinan tekstil dari Jawa. Jumlah industri pembuat kain tritik jumputan semakin berkurang, sehingga perlu dilakukan pengembangan motif pada tritik jumputan agar lebih menarik. Smock adalah salah satu teknik keterampilan menjahit dan menyulam tangan, yaitu teknik tusukan menjahit untuk membuat kerutan-kerutan yang menghasilkan motif menarik sesuai pola tertentu. Tujuan kegiatan ini adalah melakukan pengembangan teknik smock sebagai tekni...

  8. Teknik Migrasi Data Lintas DBMS dengan Menggunakan Metadata

    Directory of Open Access Journals (Sweden)

    Wahyu Hidayat

    2015-11-01

    Full Text Available Proses migrasi data biasanya dibutuhkan saat adanya perubahan sistem, format, atau tipe storage. Saat ini telah dikenal beberapa teknik dan kakas untuk melakukan migrasi data, misalnya CSV file, ODBC, SQLDump dan sebagainya. Sayangnya tidak semua teknik tersebut dapat diimplementasikan untuk migrasi data antara dua DBMS yang berbeda. Dalam penelitian ini dipaparkan sebuah teknik migrasi data yang dapat digunakan untuk migrasi data lintas DBMS. Teknik migrasi data yang dipaparkan memanfaatkan metadata yang ada di masing-masing DBMS. Proses migrasi data yang dipaparkan di sini melalui tiga tahap yaitu capture, convert dan construct. Sebuah prototype dibangun untuk menguji teknik migrasi data ini. Dengan menggunakan schema HR dilakukan uji coba migrasi data lintas DBMS antara Oracle dan MySQL. Dengan menggunakan teknik ini, migrasi data full-schema membutuhkan waktu rata-rata 20,43 detik dari DBMS Oracle ke MySQL dan 12,96 detik untuk skenario sebaliknya. Adapun untuk migrasi data parsial dibutuhkan waktu rata-rata 5,95 detik dari DBMS Oracle ke MySQL dan 2,19 detik untuk skenario sebaliknya.

  9. Profil Soft skills Mahasiswa Pendidikan Teknik Boga (PTB Fakultas Teknik Universitas Negeri Yogyakarta

    Directory of Open Access Journals (Sweden)

    Siti Hamidah

    2013-01-01

    Full Text Available Abstrak: Profil Soft skills Mahasiswa Pendidikan Teknik Boga (PTB Fakultas Teknik Universitas Negeri Yogyakarta. Penelitian ini bertujuan untuk memperoleh gambaran kekuatan dan kelemahan 9 soft skills mahasiswa PTB. Penelitian  diskriptif ini dilaksanakan di Program Studi PTB dengan menggunakan kuesioner respon. Sampel penelitian adalah semua mahasiswa semester 6. Data dianalisis secara diskriptif kuantitatif. Hasil Penelitian menunjukkan bahwa kekuatan soft skills mahasiswa PTB secara berturut adalah:  kemampuan untuk selalu belajar (72,89%, tanggung jawab (70,77%,  kerja sama dalam tim (68,61%, komitmen (67,96%, kreativitas (67,25%, disiplin (64,79%, usaha keras mencapai sukses (62,68%, pemecahan masalah (55,87%, komunikasi (49,90%. Keadaan kelemahan soft skills secara berturut: komunikasi (50,10%, pemecahan masalah (44, 13%,  usaha keras mencapai sukses (37,32%,  disiplin (35,21%, kreativitas (32,75%, komitmen (32,04%, kerjasama dalam tim (31,39%, tanggung jawab (29,23%, kemampuan untuk selalu belajar (27,11%. Dapat dinyatakan bahwa keadaan profil soft skills tersebut merupakan  hasil pengasuhan soft skills melalui pola pembelajaran model terpisah, terintegarsi dan   komplementatif. Kata kunci: profil, soft skills, mahasiswa

  10. EFEKTIVITAS TEKNIK MANAJEMEN DIRI UNTUK MENGATASI INFERIORITY FEELING

    Directory of Open Access Journals (Sweden)

    Kartika

    2016-04-01

    Full Text Available Siswa yang memiliki inferiority feeling selalu memandang rendah kemampuan yang dimiliki oleh dirinya. Untuk menutupi harga dirinya yang lemah, mereka akan melakukan kompensasi dengan cara menarik diri, bersikap agresif, ataupun membuat alasan. Sebagai upaya mengatasi inferiority feeling adalah dengan mengimplementasikan konseling kelompok dengan teknik manajemen diri. Teknik ini lebih menekankan pada pengelolaan diri yang timbul dari keinginan diri siswa. Penelitian ini bertujuan untuk menguji efektivitas konseling kelompok dengan menggunakan teknik manajemen diri untuk mengatasi inferiority feeling. Pengambilan subyek penelitian dilakukan secara non random menggunakan teknik purposive sampling. Metode penelitian yang digunakan adalah kuasi eksperimen dengan desain non equivalent pretest posttest design. Hasil penelitian menunjukkan bahwa intervensi menggunakan teknik manajemen diri efektif untuk menurunkan inferiority feeling pada subyek penelitian. Rekomendasi: (a Konselor sekolah, melakukan pemantauan secara berkala kepada siswa yang telah menjalani intervensi untuk melihat pengaruh jangka panjang dari intervensi yang telah diberikan; (b bagi peneliti selanjutnya dapat melakukan penelitian dengan keterlibatan pihak keluarga ataupun sahabat sebagai pendukung dalam memperoleh data mengenai keadaan sesungguhnya yang dialami oleh konsel

  11. Rekayasa Biopolimer Jerami Padi dengan Teknik Kopolimerisasi Cangkok dan Taut Silang

    OpenAIRE

    Henny Purwaningsih; Tun Tedja Irawadi; Zainal Alim Mas’ud; Anas Miftah Fauzi

    2017-01-01

    Kopolimerisasi cangkok dan taut silang akrilamida (AAm) terhadap jerami padi dilakukan dalamsuasana hampa udara menggunakan aliran gas N2 dengan amonium persulfat (APS) sebagai inisiatordan N,N’-metilena-bis-akrilamida (MBAAm). Pencirian dilakukan dengan teknik mikroskopipemayaran elektron (SEM) untuk melihat morfologi permukaan, teknik spektroskopi FTIR untukmelihat gugus fungsi, dan teknik DTA untuk menganalisis ketahanan produk terhadap suhu. Kajiandilakukan terhadap swelling capacity prod...

  12. Rekayasa Biopolimer Jerami Padi Dengan Teknik Kopolimerisasi Cangkok Dan Taut Silang

    OpenAIRE

    Purwaningsih, Henny; Irawadi, Tun Tedja; Mas’ud, Zainal Alim; Fauzi, Anas Miftah

    2012-01-01

    Kopolimerisasi cangkok dan taut silang akrilamida (AAm) terhadap jerami padi dilakukan dalamsuasana hampa udara menggunakan aliran gas N2 dengan amonium persulfat (APS) sebagai inisiatordan N,N'-metilena-bis-akrilamida (MBAAm). Pencirian dilakukan dengan teknik mikroskopipemayaran elektron (SEM) untuk melihat morfologi permukaan, teknik spektroskopi FTIR untukmelihat gugus fungsi, dan teknik DTA untuk menganalisis ketahanan produk terhadap suhu. Kajiandilakukan terhadap swelling capacity prod...

  13. Klare mål i natur/teknik

    DEFF Research Database (Denmark)

    Sillasen, Martin Krabbe; Paludan, Kirsten

    2004-01-01

    Projektets formål og mål Formålet med udviklingsarbejdet var på baggrund af et samarbejde mellem natur/teknik-lærere og CVU-konsulenter at få erfaringer med hensigtsmæssige samarbejdsmønstre i forhold til udviklingen af efteruddannelsestiltag for natur/teknik-lærere i et procesorienteret perspektiv......, hvor fokus vil være natur/teknik-læreres kompetenceudvikling i egen praksis. I samarbejdet indgik også refleksioner over mulige indholdsaspekter til et efteruddannelsesforløb for natur/teknik-lærere. I målbeskrivelsen nedenfor er de mulige indholdsaspekter præciseret. Målet med projektet var...... at indkredse og beskrive kriterier for en god faglig og tværfaglig forankret undervisning. Kriterierne tager udgangspunkt i: • Den gode planlægningsramme • Strukturelle og kulturelle forhold på skolen • Lærernes faglige forudsætninger • Fagteamsamarbejde • Det gode faglige/tværfaglige tema i natur...

  14. KEEFEKTIFAN TEKNIK RELAKSASI UNTUK MENURUNKAN STRES AKADEMIK SISWA SMA

    Directory of Open Access Journals (Sweden)

    Suyono Suyono

    2016-08-01

    Full Text Available Abstract: This study aims at examining the effectiveness of relaxation techniques to release students’stress and tension regarding academic within Senior High School Assádah in Gresik City. This study employed quasi-experiment design using one group pretest-posttest model. The data of this study were obtained through academic stress inventory to attain a depiction of stress level encountered by the subject. The subjects of this study were seven students of Tenth Graders in SMA Assaadah Bungah Gresik who experienced low to average stress regarding exam preparation. The data were, then, analyzed by using Wilcoxon Statistic Analysis. The result of the study indicated that relaxation technique could lower and release the level of students stress in exam preparation. Key Words: relaxation technique, student academic stress   Abstrak: Penelitian ini bertujuan untuk  menguji keefektifan teknik relaksasi untuk menurunkan stres akademik siswa SMA Ass’adah di Kota Gresik dengan menggunakan rancangan kuasi eksperimen dengan model “one group pretest posttest design. Pengumpulan data dengan menggunakan inventori stres akademik tujuannya untuk memperoleh gambaran tingkat stres akademik pada subjek penelitian. Subjek penelitian adalah siswa yang mengalami stres akademik sedang dan rendah  dalam menghadapi ujian berjumlah 7 orang siswa pada kelas X SMA Assaadah Bungah Gresik. Teknik analisis data dengan menggunakanan analisis statistic Wilcoxon. Hasil penelitian menunjukkan adanya penurunan tingkat stres akademik menjelang ujian sesudah subjek mendapatkan layanan dengan teknik  relaksasi. Kata kunci: Teknik relaksasi, stres akademik siswa

  15. Sistem Informasi Penampil Pengumuman Fakultas Teknik Universitas Diponegoro

    Directory of Open Access Journals (Sweden)

    Fajar Yogi Hernawan

    2017-01-01

    Full Text Available Abstract - Engineering Faculty is the biggest faculty with the highest number of departements and students in the Diponegoro University. The idea made SIPP (System Information Viewer Announcements Faculty of Engineering, University of Diponegoro appears is to help disseminate information and stories of pride born from Engineering Faculty to become the impetus and motivation for more achievement. SIPP maked with 5(five stages: requirement, analysis, design, implementation, testing. SIPP is built using the programming language PHP, HTML, CSS, Bootstrap, Javascript, and MySQL database. SIPP is expected to convey information and the pride stories of the Engineering Faculty in the multimedia. The output of the SIPP is the information shown via LCD TV screen ratio of 16: 9 which blend of images, video and running text. SIPP expected to be implemented in the lobby Engineering Faculty dean and in every department in it. Users SIPP is divided into 2 (two they are admin faculty as the main admin and admin department as sub-admin. SIPP tested with 2 (two test that is functionality testing by black box and performance testing with performance-analyzer application. With the implementation of SIPP environment Faculty of Engineering will be an additional alternative for the community Faculty of Engineering to obtain information. Keywords - Information, SIPP, multimedia, Engineering Faculty.   Intisari – Fakultas Teknik adalah fakultas dengan jumlah jurusan dan mahasiswa terbanyak di Universitas Diponegoro. Gagasan dibuatnya SIPP (Sistem Informasi Penampil Pengumuman Fakultas Teknik Universitas Diponegoro muncul adalah untuk membantu menyebarkan informasi dan cerita kebanggaan dari Fakultas Teknik yang menjadi dorongan dan motivasi untuk lebih berprestasi. SIPP dibuat dengan 5(lima tahap : rencana kebutuhan, analisis kebutuhan, perancangan desain, perancangan sistem, dan pengujian. SIPP dibangun menggunakan bahasa pemrograman PHP, HTML, CSS, Bootstrap

  16. Eksplorasi Pewarnaan Teknik Smock Kombinasi Tritik Jumputan untuk Produk Fashion

    Directory of Open Access Journals (Sweden)

    Suryawati Ristiani

    2016-04-01

    Full Text Available ABSTRAKKain tritik jumputan merupakan salah satu jenis kerajinan tekstil dari Jawa. Jumlah industri pembuat kain tritik jumputan semakin berkurang, sehingga perlu dilakukan pengembangan motif pada tritik jumputan agar lebih menarik. Smock adalah salah satu teknik keterampilan menjahit dan menyulam tangan, yaitu teknik tusukan menjahit untuk membuat kerutan-kerutan yang menghasilkan motif menarik sesuai pola tertentu. Tujuan kegiatan ini adalah melakukan pengembangan teknik smock sebagai teknik dalam pewarnaan yang dikombinasikan dengan teknik tritik jumputan sehingga dapat meningkatkan daya saing produk fashion tritik jumputan. Metode dalam kegiatan ini adalah melakukan survey langsung ke industri tritik jumputan serta eksplorasi literatur. Data-data yang diperoleh kemudian dianalisa dari segi proses maupun desain motifnya. Tahap berikutnya dilakukan ujicoba pewarnaan dengan mengkombinasikan dua teknik yaitu teknik smock dan teknik tritik jumputan. Ujicoba yang dilakukan tercipta desain motif baru yang indah. Hasil kegiatan diperoleh 23 desain motif baru. Pengamatan visual menunjukkan hasil pewarnaan yang paling optimal adalah pada kain mori Primissima. Berdasarkan hasil uji labolatorium, tekstil kerajinan ini mempunyai ketahanan luntur warna terhadap pencucian, keringat, dan sinar yang bagus, dengan nilai hasil uji 4 – 5. Sedangkan nilai ketahanan luntur warna terhadap gosokan, adalah 3. Dapat dikatakan hasil pewarnaan dengan mengkombinasikan dua teknik ini memenuhi standar kualitas sebagai produk bahan sandang. Ujicoba pasar yang dilakukan menunjukkan bahwa ternyata respon masyarakat sangat bagus. Hasil uji kesukaan responden mendapatkan nilai sangat bagus sebanyak 55%, dan bagus sebanyak 45%. Teknik pewarnaan smock kombinasi tritik jumputan ini prosesnya sederhana, tidak memerlukan alat khusus, sehingga berpotensi untuk dikembangkan menjadi sumber daya ekonomi yang signifikan. Kata kunci: ABSTRACTTritik jumputan is one kind of craft textile

  17. TEKNIK PENGENDALIAN PENYAKIT BENIH PILANG (Acacia leucophloea Wild.

    Directory of Open Access Journals (Sweden)

    Tati Suharti

    2016-09-01

    Full Text Available Salah satu faktor yang mempengaruhi daya berkecambah benih adalah serangan penyakit benih. Penyakit yang umumnya berupa cendawan terbawa benih dapat menimbulkan kerusakan pada benih diantaranya mutu dan daya simpan benih menjadi menurun. Teknik pengendalian secara fisik dapat dilakukan dengan penggunaan kemasan plastik yang hampa udara (vacum, sedangkan secara kimia dengan penggunaan fungisida benomil. Teknik pengendalian penyakit benih pilang selama penyimpanan yaitu dengan perlakuan pengepresan vacum. Perlakuan ini dapat menjaga viabilitas benih dan menekan infeksi cendawan Aspergillus sp. Pada umur simpan 1 tahun, perlakuan ini menghasilkan daya berkecambah sebesar 47 % dan persentase infeksi Aspergillus sp. sebesar 18% sedangkan perlakuan plastik menghasilkan daya berkecambah sebesar 34,67 % dan persentase infeksi Aspergillus sp. sebesar 50 %.

  18. PENERAPAN METODE PENDEKATAN TEKNIK UNTUK MENINGKATKAN KEANDALAN SISTEM DISTRIBUSI

    Directory of Open Access Journals (Sweden)

    Rukmi Sari Hartati

    2010-07-01

    Full Text Available Metode pendekatan teknik dipergunakan untuk meningkatkan keandalan sistem distribusi dengan menentukan lokasi recloser yang optimal pada penyulang- penyulang yang akan ditingkatkan keandalannya, sehingga diperoleh nilai indeks keandalan yang lebih baik. Telah dilakukan penelitian dengan menggunakan metode tersebut untuk meningkatkan keandalan pada penyulang Penebel dan Marga untuk memenuhi target PLN ke depan yakni mencapai WCS (World Customer Service serta WCC (World Class Company yaitu SAIFI = 3 kali/pelanggan/tahun dan SAIDI = 100 menit/pelangggan/tahun. Dari hasil penelitian pada 2 penyulang tersebut diperoleh nilai indeks keandalan SAIDI dan SAIFI untuk kedua penyulang tersebut sudah mendekati target WCS dan jauh lebih baik dibandingkan dengan kondisi sebelum dipasang recloser. Sehingga dapat disimpulkan bahwa penggunaan metode pendekatan teknik untuk meningkatkan keandalan sistem distribusi cocok untuk diterapkan, terutama pada sistem distribusi di Bali.

  19. Teknik Penanaman Eboni (Diospyros Celebica Bakh.) Di Daerah Agak Kering

    OpenAIRE

    Hendromono, Hendromono

    2008-01-01

    Pohon eboni sebagai penghasil kayu mewah merupakan jenis yang hanya tumbuh alami di Sulawesi. Harga kayu eboni yang mahal mengakibatkan pohonnya dieksploitasi secara berlebihan dihabitat alarnnya. Untuk mencegah eboni dari kepunahan diperlukan konservasi eboni secara in-situ dan ex-situ. Tujuan penelitian adalah untuk mengetahui teknik penanaman eboni di daerah tropik yang beriklim agak kering. Penelitian menggunakan rancangan acak lengkap berkelompok dalam percobaan faktorial 2 x 3. Perlaku...

  20. Kajian Keselamatan dan Kesehatan Kerja Bengkel di Jurusan Pendidikan Teknik Sipil dan Perencanaan Fakultas Teknik Uny

    Directory of Open Access Journals (Sweden)

    Nur Hidayat

    2016-05-01

    Full Text Available The objective of this study was to analyse: (1 the plan (2 the implementation, and (3 the evaluation of the Occupational Safety and Health (OSH management in the workshop of the Department of Civil Engineering and Planning Education, Faculty of Engineering, Yogyakarta State University (YSU. This study was categorised into descriptive study that scientifically explained the workplace environment of the workshop specifically in terms of the OSH management. The data collection techniques used observations, interviews and questionnaires. The data of this study was analysed descriptively. This study presented the detailed descriptions of the collected data in the field. The results revealed (1 It is crucial to develop a more systematic OSH management plan in the workshop of the Department of Civil Engineering and Planning Education, Faculty of Engineering, YSU (2 the planning policies and the implementation of the OSH management need a continual improvement  and (3 the evaluation of the OSH management should be conducted simultaneously by the stakeholders, the lecturers and the technicians. (4 The OSH policy in the practices should be properly organised to promote the OSH culture in the workshop. (5 The OSH management control and review were prioritised for fostering the effectiveness of the OSH management implementation. Penelitian ini bertujuan untuk mengetahui perencanaan, pelaksanaan, dan  evaluasi Keselamatan dan Kesehatan Kerja (K3 di Bengkel Jurusan Pendidikan Teknik Sipil dan Perencanaan FT UNY. Penelitian ini merupakan penelitian deskriptif (descriptive reasearch yang memaparkan secara ilmiah keadaan di lingkungan bengkel khususnya mengenai aspek K3. Metode pengumpulan data menggunakan observasi, wawancara, dan angket. Analisis data menggunakan analisis deskriptif. Penelitian ini mendeskripsikan secara detail terhadap apa yang ditemukan dalam pengambilan data. Hasil penelitian ini menunjukkan bahwa

  1. Meningkatkan Kemampuan Prososial Siswa Melalui Layanan Informasi dengan Teknik Bibliotherapy

    Directory of Open Access Journals (Sweden)

    Kiftiyah Riris Novita

    2017-12-01

    Full Text Available Tujuan penelitian ini adalah untuk mengetahui kemampuan prososial siswa sebelum dan setelah diberikan layanan informasi dengan teknik bibliotherapy di SD N Sekaran 01, Semarang. Penelitian eksperimen ini menggunakan one group pretest-posttest design. Populasi kelas enam di SD N Sekaran 01 berjumlah 40 siswa. Teknik pengambilan sampel menggunakan purposive sampling didasarkan atas tujuan dan pertimbangan tertentu, kemudian diambil sampel dengan jumlah 20 siswa. Pengumpulan data dilakukan dengan menggunakan skala prososial berjumlah 40 item. Analisis data menggunakan deskriptif persentase dan uji t-test. Hasil penelitian menunjukan bahwa persentase siswa naik dari 51% menjadi 83%, dan hasil uji thitung lebih besar dari ttabel yaitu 17.333 > 2.086. maka dapat disimpulkan bahwa layanan informasi dengan teknik bibliotherapy efektif dalam meningkatkan perilaku prososial siswa.   The purpose of this research is to know the prosocial ability of student before and after the given information service with the technique of bibliotherapy in SD N Sekaran 01, Semarang. This experiment uses one-group pretest and post test design. The population of this class is sixth grade in SD N Sekaran 01 amounted fourty students. Sample retneval technique used is a purposive sampling based upon the purpose and particular consideration so obtained sample amounted to twenty students. Data collection uses prosocial scale 40 items. Data analysis uses descriptive percentage and t-test. This research shows that the result increases percentage of 51% to 83% and the result is ttabel > ttabel : 17.333 > 2.086. So it can be conclution that information service with bibliotherapy technique is effective to increases behavior of prosocial students.

  2. Pengembangan Teknik Jahit Celup (Tritik dengan Pola Geometris

    Directory of Open Access Journals (Sweden)

    Bintan Titisari

    2014-10-01

    Full Text Available Teknik jahit celup biasa dikenal dengan istilah tritik, yang berarti titik, merupakan teknik tekstil kelompok celup rintang. Tritik adalah cara menghias kain putih dengan menjahit jelujur lalu ditarik kemudian dicelup dan motif terbentuk setelah benang dilepaskan. Teknik tritik digunakan untuk membuat kain sasirangan, kain tradisional Kalimantan Selatan, Indonesia. Proses menjahit pada tritik dikerjakan secara tradisional tanpa ketentuan yang jelas, sehingga pengembangan desain motif belum maksimal. Melihat kondisi tersebut, penelitian  ini menggunakan pola geometris pada teknik tritik untuk melihat kemungkinan dihasilkan motif berbeda. Dengan  metode eksperimen kualitatif didapat ketentuan mengenai aturan jahitan yang diaplikasikan pada pembuatan pola geometris. Penggunaan pola geometris menghasilkan motif lebih teratur dengan tetap terkesan samar sebagai ciri khas tritik. Pewarnaan bertahap dan pengaturan jarak menghasilkan efek ilusi optik (kedalaman, arah, dan gerak. Motif tersebut diaplikasikan pada produk fashion dengan menonjolkan efek ilusi optik untuk menghasilkan siluet pada pakaian wanita.Kata kunci: geometri; jahit celup rintang; pola; sasirangan; tritik.Resist stitch-dyeing, also known locally as tritik (lit. dots, is resist dye textile weaving technique. Tritik is a method to embellish white cloth by tacking, which is then dyed and removed. The motif is formed after the thread is removed. Tritik methods and techniques are less popular compared to batik or dyed ikat. It is, however, used in making sasirangan cloth, a traditional cloth from South Kalimantan, Indonesia. The stitching has always been done traditionally due to the lack of clear convention on stitching as a resist-media. Thus, development of motif designs is not in full capacity. Taking into consideration the above, this study is carried out to create new geometric patterns using tritik techniques. Qualitative experiment methods are used to obtain ideal stitching

  3. VIDEO ANIMASI 3D PENGENALAN RUMAH ADAT DAN ALAT MUSIK KEPRI DENGAN MENGUNAKAN TEKNIK RENDER CEL-SHADING

    OpenAIRE

    Jianfranco Irfian Asnawi; Afdhol Dzikri

    2016-01-01

    Animasi ini berjudul "video animasi 3D rumah adat dan alat musik Kepulauan Riau dengan menggunakan teknik render cel-shading" merupakan video yang bertujuan memperkenalkan alat-alat musik yang berasal dari kepulauan riau, Animasi ini akan diterapkan dengan menggunakan teknik render cel-shading. Cel-shading adalah teknik render yang menampilkan grafik 3D yang menyerupai gambar tangan, seperti gambar komik dan kartun. Teknik ini juga sudah di terapkan dalam game 3D yang ternyata menarik banyak ...

  4. Correlation between the surface chemistry and the atmospheric corrosion of AZ31, AZ80 and AZ91D magnesium alloys

    International Nuclear Information System (INIS)

    Feliu, S.; Pardo, A.; Merino, M.C.; Coy, A.E.; Viejo, F.; Arrabal, R.

    2009-01-01

    X-ray photoelectron spectroscopy (XPS) was used in order to investigate the correlation between the surface chemistry and the atmospheric corrosion of AZ31, AZ80 and AZ91D magnesium alloys exposed to 98% relative humidity at 50 deg. C. Commercially pure magnesium, used as the reference material, revealed MgO, Mg(OH) 2 and tracers of magnesium carbonate in the air-formed film. For the AZ80 and AZ91D alloys, the amount of magnesium carbonate formed on the surface reached similar values to those of MgO and Mg(OH) 2 . A linear relation between the amount of magnesium carbonate formed on the surface and the subsequent corrosion behaviour in the humid environment was found. The AZ80 alloy revealed the highest amount of magnesium carbonate in the air-formed film and the highest atmospheric corrosion resistance, even higher than the AZ91D alloy, indicating that aluminium distribution in the alloy microstructure influenced the amount of magnesium carbonate formed.

  5. Pengaruh waktu kontak terhadap kualitas sambungan hasil las gesek (Friction Welding Magnesium AZ-31

    Directory of Open Access Journals (Sweden)

    Solihin Solihin

    2018-01-01

    Full Text Available Abstrak: Pengelasan merupakan salah suatu proses penyambungan dua atau lebih bahan teknik, dengan atau tanpa peroses pencairan logam dasarnya. Teknologi Las Gesek (Friction Welding, FW merupakan salah satu teknik pengelasan padat atau pengelasan tanpa proses pencairan (solid-state welding. Pembangkitan panas dalam proses FW dihasilkan dengan cara menggesekkan permukaan material las (base metal hingga mencapai temperatur penyambungannya (semi-solid temperature atau sekitar 80% dari temperature cair bahan, dan dalam hal Magnesium AZ31 adalah sekitar temperatur 5500C. Setelah bahan mencapai temperatur semi-solid tersebut, kemudian diberi tekanan agar terjadi proses penyambungan. Penelitian ini bertujuan untuk mengetahui pengaruh variasi proses terhadap kualitas hasil pengelasan gesek, yang meliputi: kekuatan tarik, struktur makro, dan nilai kekerasan bahan hasil las. Parameter pengujiannya adalah variasi waktu kontak las, yaitu selama 3, 5, dan 10 menit. Kecepatan putar spindle selama proses pengelasan ditetapkan 1400 rpm. Hasil pengelasan menunjukkan bahwa waktu kontak gesek 3 menit menghasilkan kekuatan tarik tertinggi (16,78 MPa, bila dibandingkan dengan dua parameter lain. Hasil uji keras pada daerah las (stir zone menunjukkan angka kekerasan rata-rata yang relative konsisten, atau sebesar 60 HRE untuk semua parameter, sedangkan angka kekerasan rata-rata di daerah terpengaruh panas (heat affected zone, HAZ untuk waktu kontak gesek 3, 5 dan 10 menit secara berturut-turut adalah sebesar 69,6; 64,6; dan 60,6 HRE. Hasil penelitian awal ini memberikan potensi studi lanjutan pada berbagai parameter pengelasan lain agar didapatkan kualitas sambungan las gesek yang optimum untuk proses pengelasan gesek Magnesium AZ-31. Kata Kunci: Las gesek, Magnesium AZ-31, struktur makro, cacat void. Abstract: Welding is a process technology aiming to join two or more materials. Friction Welding (FW is including in a solid-state technology cluster, where the heat is

  6. Pengaruh Layanan Penguasaan Konten Teknik Mind Mapping Terhadap Keefektifan Belajar

    Directory of Open Access Journals (Sweden)

    Ajeng Pudak Pinasti

    2015-04-01

    Full Text Available Penelitian ini bertujuan untuk membuktikan apakah layanan penguasaan konten dengan metode mind mapping memiliki pengaruh terhadap keefektifan belajar siswa. Penelitian ini didasari atas kurangnya keefektifan belajar siswa. Populasi dan sampel dalam penelitian ini adalah semua siswa kelas XI AP SMK YPE Sampang, Cilacap yang berjumlah 40 siswa. Teknik pengumpulan data pada penelitian ini adalah skala keefektifan belajar dan soal tes. Metode analisis data menggunakan deskriptif persentase dan uji t-test. Hasil penelitian menunjukkan bahwa keefektifan belajar siswa sebelum mendapatkan treatment dalam kategori sedang dan sesudah diberikan treatment menunjukkan kategori tinggi. Teknik mind mapping bisadigunakan untuk  mempermudah siswa memahami dan mengingat materi pelajaran dengan lebih cepat dan sederhana. Hasil uji  t-test dengan taraf signifikansi 5% menunjukan thitung (5,45 dan ttabel (2,021 sehingga thitung> ttabel. Berdasarkan hasil penelitian yang telah dilakukan, dapat disimpulkan bahwa layanan penguasaan konten dengan teknik mind mapping memberikan pengaruh positif terhadapt keefektifan belajar siswa. Oleh karena itu, diharapkan guru BK dapat memsosialisasikan pemberian layanan penguasaan konten sebagai alternatif meningkatkan keefektifan belajar. The objective of this research is to prove about the impact of  content mastery servise with mind mapping technique to the effectiveness of student learning. This research was based on the lack of effectiveness of student learning. The Population at the same time study sample are all of the XI AP grade students of SMK YPE Sampang, Cilacap, which consist of 40 students. Data collection  technique used effectiveness of student learning scale and a test. Methods of data analysis using descriptive percentages and t-test. Research result showed that the effectiveness of student learning before the treatment was in medium category. After the treatment, effectiveness of student learning was in high

  7. A Comparative Electrochemical Study of AZ31 and AZ91 Magnesium Alloy

    Directory of Open Access Journals (Sweden)

    S. A. Salman

    2010-01-01

    Full Text Available A comparative study has been carried out on AZ31 and AZ91 magnesium alloys in order to understand the electrochemical behavior in both alkaline and chloride containing solutions. The open circuit potential (OCP was examined in 1 M NaOH and 3.5 mass % NaCl solutions. AZ31 magnesium alloy shows several potential drops throughout the immersion in 1 M NaOH solution, though AZ91 does not show this phenomenon. The specimens were anodized at a constant potential of 3 V for 30 minutes at 298 K in 1 M NaOH solution. The anticorrosion behavior of the anodized specimens was better than those of nonanodized specimens. The anodized AZ91 has better corrosion resistance compared to nonanodized specimen and anodized AZ31 magnesium alloy.

  8. Keefektifan Konseling Behavioral Teknik Modeling dan Konseling Analisis Transaksional Teknik Role Playing untuk Meminimalkan Kecenderungan Perilaku Agresif Siswa Sekolah Menengah Atas

    Directory of Open Access Journals (Sweden)

    I Ketut Gading

    2017-11-01

    Full Text Available Abstract: This study aims to determine the effectiveness of behavioral counseling using modeling technique and counseling transactional analysis using role playing technique to minimize student’s tendency of aggressive behavior. This experimental research with pretest-posttest control group design is taking samples using purposive sampling technique. The sample were 18 tenth grade students from Senior High School Laboratorium Universitas Pendidikan Ganesha who have high aggressive behavior. 18 sample were randomly assigned to three group, that is: (1 experimental group of behavioral counseling using modeling technique; (2 counseling transactional analysis using role playing technique group; and (3 control group. Data on aggressive behavior tendency before and after treatment were collected using questionnaire of aggressive behavior, then analyzed by t test. The results show: (1 behavioral counseling using modeling technique were effective to minimize the tendency of aggressive behavior; (2 counseling transactional analysis using role playing technique were effective to minimize the aggressive behavior; and (3 counseling transactional analysis using role playing technique were more effectively minimizes the tendency of aggressive behavior rather than behavioral counseling using modeling technique. Abstrak: Penelitian ini bertujuan untuk mengetahui keefektifan konseling behavioral teknik modeling dan konseling analisis transaksional teknik role playing untuk meminimalkan kecenderungan perilaku agresif siswa. Penelitian eksperimen dengan rancangan pretest-posttest control group design ini mengambil sampel dengan teknik purposive sampling. Sampel terdiri dari 18 orang siswa kelas X Sekolah Menengah Atas (SMA Laboratorium Universitas Pendidikan Ganesha yang memiliki perilaku agresif tinggi. 18 sampel dibagi secara acak dan merata pada tiga kelompok, yaitu: (1 kelompok eksperimen yang mendapatkan perlakuan konseling behavioral teknik modeling; (2

  9. Penatalaksanaan Repair Palatoplasty dengan Teknik Furlow Double Opposing Z Plasty

    Directory of Open Access Journals (Sweden)

    Pingky Krisna Arindra

    2015-06-01

    metode Furlow double opposing z plasty dengan kombinasi insisi lateral, dan didapatkan hasil menutupnya celah di palatum mole sampai dengan uvula. Telah dilakukan operasi repair palatoplasi dengan metode Furlow double opposing z plasty. Teknik ini dilakukan untuk menghindari insisi yang terlalu luas dikarenakan terdapatnya jaringan fibrous yang tebal pada mukosa palatum pasca operasi sebelumnya. Tujuan studi kasus adalah untuk mengetahui kemampuan teknik Furlow Double Opposing Z Plasty sebagai prosedur repair palatoplasty.   Repair Palatoplasty Management with Furlow Double Opposing Z Plasty Technique. Cases of cleft lip and palate are one of the deformity disorders that often occur. There are variety of clinical appearance ranging from incomplete to complete cases. Clinical appearance with different width requires proper surgical technique. Patients with cleft lip and palate had undergone surgical intervention, so that they needed surgical correction to repair the result or failure of the previous surgery. A Four year old boy complain there was cleft on the soft palate. The patient was diagnosed with labiognatopalatoscisis. The patient had undergone two stages of cleft lip surgery and twice of cleft palate surgery with pushback method and repair with z plasty, however the result was unsatisfactory. Further, the patient underwent repair palatoplasty surgery with Furlow double opposing z plasty method combined with lateral relaxing insicion. The result in the post surgery was the closure of cleft soft palate up to uvula. Repair palataplasty surgery has been done with Furlow double opposing z plasty method. This technique could avoid extended incision due to thick fibrous tissue on the palatum mucosa as the result of serial previous surgery. The aim of this case case study is to determine the technical capabilities of Furlow Double Opposing Z Plasty as palatoplasty repair procedure.

  10. EnviroAtlas - Phoenix, AZ - Block Groups

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset is the base layer for the Phoenix, AZ EnviroAtlas area. The block groups are from the US Census Bureau and are included/excluded based on...

  11. The A-Z of electronuclear power

    International Nuclear Information System (INIS)

    Temmerman, G. de; Chedorge, D.

    1992-01-01

    Both a bilingual translation aid and a reference book, 'The A-Z of Electronuclear Power' covers the full range of electronuclear activities and the English and French terminology relating to the different phases of the modern industrial process

  12. PENGEMBANGAN SISTEM DATABASE HASIL SKRIPSI DAN TUGAS AKHIR PADA JURUSAN TEKNIK ELEKTRO UNNES

    Directory of Open Access Journals (Sweden)

    Tatyantoro Andrasto

    2013-02-01

    Full Text Available Belum adanya database hasil skripsi dan tugas akhir pada jurusan Teknik Elektro UNNES yang baik berakibat memungkinkannya terjadi duplikasi atau penyalahgunaan hasil skripsi atau tugas akhir tahun yang lalu digunakan lagi untuk proposal skripsi atau tugas akhir pada tahun sekarang atau yang akan datang. Sehingga hal ini akan memberikan efek negatif pada perkembangan karya ilmiah/akademik di jurusan Teknik Elektro UNNES khususnya dan dunia akademik di Indonesia pada umumnya. Metode yang diterapkan pada pembuatan database ini adalah membuat prototype kemudian dilakukan proses mencoba dan meminta pendapat orang yang mendata dan menyimpan hasil skripsi dan tugas akhir di jurusan Teknik Elektro UNNES. Hasil penelitian ini berupa sistem database berbasis web sehingga dapat dilakukan input data, edit data maupun melihat data skripsi dan tugas akhir yang ada di jurusan Teknik Elektro UNNES dari manapun, tidak harus datang ke UNNES hanya untuk melihat maupun melakukan edit data oleh admin.

  13. Cold-Sprayed AZ91D Coating and SiC/AZ91D Composite Coatings

    Directory of Open Access Journals (Sweden)

    Yingying Wang

    2018-03-01

    Full Text Available As an emerging coating building technique, cold spraying has many advantages to elaborate Mg alloy workpieces. In this study, AZ91D coatings and AZ91D-based composite coatings were deposited using cold spraying. Coatings were prepared using different gas temperatures to obtain the available main gas temperature. Compressed air was used as the accelerating gas, and although magnesium alloy is oxidation-sensitive, AZ91D coatings with good performance were obtained. The results show that dense coatings can be fabricated until the gas temperature is higher than 500 °C. The deposition efficiency increases greatly with the gas temperature, but it is lower than 10% for all coating specimens. To analyze the effects of compressed air on AZ91D powder particles and the effects of gas temperature on coatings, the phase composition, porosity, cross-sectional microstructure, and microhardness of coatings were characterized. X-ray diffraction and oxygen content analysis clarified that no phase transformation or oxidation occurred on AZ91D powder particles during cold spraying processes with compressed air. The porosity of AZ91D coatings remained between 3.6% and 3.9%. Impact melting was found on deformed AZ91D particles when the gas temperature increased to 550 °C. As-sprayed coatings exhibit much higher microhardness than as-casted bulk magnesium, demonstrating the dense structure of cold-sprayed coatings. To study the effects of ceramic particles on cold-sprayed AZ91D coatings, 15 vol % SiC powder particles were added into the feedstock powder. Lower SiC content in the coating than in the feedstock powder means that the deposition efficiency of the SiC powder particles is lower than the deposition efficiency of AZ91D particles. The addition of SiC particles reduces the porosity and increases the microhardness of cold-sprayed AZ91D coatings. The corrosion behavior of AZ91D coating and SiC reinforced AZ91D composite coating were examined. The Si

  14. Pemanfaatan Teknik Ko-Kristalisasi Untuk Produksi Serbuk Ekstrak Sirsak

    Directory of Open Access Journals (Sweden)

    Lukman Junaidi

    2013-12-01

    Full Text Available Research on application of co-crystallization technique on production of soursop extract powder conducted to diversify soursop product that could be used as industrial commodity. Treatment on this research was influence of: (1 anti-caking magnesium oxide (MO, magnesium carbonate (MC, and magnesium silicate (MS, and (2 storage period (0, 1, 2, and 3 months, on the characteristics of soursop powder quality. The results showed co-crystallization could be applied to produce soursop powder that met the requirements of SNI 01-4320-1996. Based on its quality characteristics, soursop powder oursop powder MC resulted a better quality compared to s MO and s MS. MC had a quality characteristics: oursop powder Soursop powder water content 1.89%, pH 4.17, sugar content 83.75%, vitamin C 42.7  total soluble solids 98.1%, TPC mg/100g, 55 colonies/g, soursop powder until coliform < 3 MPN, and contain no mold and yeast. Storage of 3 months increased water content, pH, and TPC, and contrarily decreased sugar content, vitamin C  total soluble solids.  Based on the quality characteristics, soursop powder that , and was stored for 3 months still met the SNI 01-4320-1996 requirements.ABSTRAK Penelitian pemanfaatan teknik ko-kristalisasi untuk produksi serbuk ekstrak sirsak dilakukan untuk diversifikasi produk olahan buah sirsak yang dapat dijadikan komoditas industri. Perlakuan yang diamati meliputi pengaruh: (1 penggunaan jenis anti-kempal magnesium oksida (MO, magnesium karbonat (MC, dan magnesium silikat (MS dan (2 masa simpan (0, 1, 2, dan 3 bulan terhadap karakteristik mutu serbuk sirsak. Hasil penelitian menunjuk-kan bahwa teknik ko-kristalisasi dapat dimanfaatkan untuk menghasilkan serbuk sirsak yang memenuhi persyaratan mutu SNI 01-4320-1996. Berdasarkan karakteristik mutunya, serbuk sirsak MC memberikan hasil yang lebih baik dibandingkan dengan serbuk sirsak MS dan serbuk sirsak MO.  Serbuk sirsak MC memiliki karakteristik mutu: kadar air 1,89%, pH 4

  15. Pemanfaatan Limbah Kulit Jagung untuk Produk Modular dengan Teknik Pilin

    Directory of Open Access Journals (Sweden)

    Artarita Ginting

    2016-04-01

    Full Text Available ABSTRAKPengembangan industri kreatif tanpa limbah merupakan persyaratan penting bagi keseimbangan yang baik antara peningkatan usaha industri, daya dukung alam dan kesejahteraan manusia yang tinggal di lingkungan tersebut. Sangat sedikit usaha para pelaku industri untuk mengoptimalkan manfaat sebuah hasil alam hingga tidak menghasilkan limbah sama sekali. Kulit jagung merupakan salah satu limbah rumah tangga dan industri kecil yang jumlahnya berlimpah namun kurang optimal dalam pemanfaatannya. Produksi dan konsumsi jagung merupakan bagian dari satu sistem kehidupan yang utuh sehingga patut dipertimbangkan strategi pelaksanaannya agar daya dukung lingkungan tetap kuat. Penelitian eksperimental bahan kulit jagung ini bertujuan memanfaatkan limbah kulit jagung sebagai bahan alternatif produk kerajinan secara optimal tanpa menghasilkan limbah kembali. Dalam penelitian yang menggunakan metode penelitian eksperimen bahan posttest-only, diperoleh kesimpulan bahwa pengawetan dengan rendaman CH3COOH selama 24 jam dan proses penjemuran selama 3 jam pada jam 9 pagi hingga jam 12 siang menghasilkan serat kulit jagung yang memiliki kekuatan tarik paling tinggi dan warna yang cerah. Sedangkan teknik pemilinan membantu untuk menambah kekuatan tarik melalui kepadatan dari hasil pilinan kulit jagung. Hasil penelitian eksperimen bahan digunakan untuk membuat spesifikasi performa produk bagi konsep perancangan desain rak anyam modular yang diwujudkan dengan teknik sambung pasak yang praktis dalam penggunaannya. Kata kunci: tanpa limbah, pilinan kulit jagung, kaleng bekas, modular ABSTRACT  The development of zero waste creative industry is a vital prerequisite for a healthy balance between industrial development, nature support capacity and community welfare within the area. There are only a few number of industries that consider to optimalized their raw materials towards zero waste goal. Corn husk is one of the industrial and residential waste that is under

  16. IKAN GABUS (Channa striata MANFAAT PENGEMBANGAN DAN ALTERNATIF TEKNIK BUDIDAYANYA

    Directory of Open Access Journals (Sweden)

    Nurbakti Listyanto

    2009-06-01

    Full Text Available Ikan gabus (Channa striata merupakan jenis ikan yang bernilai ekonomis. Di Indonesia penyebarannya antara lain di Sumatera, Jawa, Kalimantan, Sulawesi, dan Papua. Spesies ini memiliki rasa yang khas, tekstur daging tebal dan putih sehingga harganya pun cukup mahal baik dalam bentuk segar maupun kering (ikan asin. Selain itu, memiliki kandungan albumin yang diperlukan tubuh manusia dalam mengatasi berbagai penyakit terutama yang disebabkan berkurangnya jumlah protein darah. Ikan ini termasuk salah satu jenis ikan karnivora air tawar dikarenakan sifatnya yang gemar memangsa ikan-ikan kecil sebagai pakannya. Walaupun memiliki potensi strategis, serta kegunaan yang luas dalam industri pangan maupun farmasi, namun di Indonesia masih belum banyak dibudidayakan karena belum dikuasai teknik budidayanya. Pemeliharaan bersama ikan mujair di kolam, penggunaan campuran pakan buatan kaya nutrisi, serta pemanfaatan tanaman air dalam proses pemijahan merupakan alternatif budidaya yang perlu dikembangkan.

  17. VIDEO ANIMASI 3D PENGENALAN RUMAH ADAT DAN ALAT MUSIK KEPRI DENGAN MENGUNAKAN TEKNIK RENDER CEL-SHADING

    Directory of Open Access Journals (Sweden)

    Jianfranco Irfian Asnawi

    2016-11-01

    Full Text Available Animasi ini berjudul "video animasi 3D rumah adat dan alat musik Kepulauan Riau dengan menggunakan teknik render cel-shading" merupakan video yang bertujuan memperkenalkan alat-alat musik yang berasal dari kepulauan riau, Animasi ini akan diterapkan dengan menggunakan teknik render cel-shading. Cel-shading adalah teknik render yang menampilkan grafik 3D yang menyerupai gambar tangan, seperti gambar komik dan kartun. Teknik ini juga sudah di terapkan dalam game 3D yang ternyata menarik banyak perhatian peminat. Teknik ini akan di terapkan kedalam animasi 3D "video animasi rumah adat dan alat musik kepulauan riau dengan menggunakan teknik render cel-shading" Animasi di rancang menggunakan skenario dan storyboard kemudian di implementasikan dalam software 3D MAYA AUTODESK dengan menggunakan teknik render cel-shading. Setelah diterapkan maka di dapatkan definisi keberhasilan dari teknik render cel shading di bandingkan dengan teknik render global illumination seperti dari kecepatan dalam merender dan tingkat kecerahan warna pada video. Kata kunci: animasi, game 3D, cel-shading.

  18. IDENTIFIKASI TEKNIK-TEKNIK PENGUBAHAN TINGKAH LAKU DALAM PENERAPAN PEMIKIRAN IBNU QOYYIM AL-JAUZIYYAH UNTUK PENGENTASAN KORBAN SEKS BEBAS DAN HOMOSEKS (KAJIAN ANALISIS HERMENEUTIKA BERSUSUN

    Directory of Open Access Journals (Sweden)

    Aswar Aswar

    2016-02-01

    Full Text Available The purposes of this research were to obtain (1 Descriptive-interpretative information  related to the intervention targets of behavior modification, (2 Descriptive-interpretative information  related with the analysis and diagnosis, and (3 Descriptive-interpretative understanding on each form of treatment that can be used as a technique of behavior modification for freesex and homosexual. Data were collected through a text document of Ibnu Qoyyim al-Jauziyyah thought, observation and interview with research subjects in the field. The study used a qualitative approach with multilevel hermeneutic analysis. Results of the study were: (1 Intervention target of modification behavior focusing on thought/belief modification; (2 analysis and diagnosis around the unhealthy thoughts/beliefs and habit/action; (3 it was founded treatment form to alleviate freesex victim and homosexual in the form of mind intervention techniques, lust disorder alleviation techniques, homosexual alleviation techniques, and worship as an alleviation techniques. Tujuan penelitian ini untuk memperoleh (1 keterangan deskriptif-interpretif terkait sasaran intervensi pengubahan tingkah laku, (2 keterangan deskriptif-interpretif terkait analisis dan diagnosis, dan (3 pemahaman deskriptif-interpretif pada tiap bentuk perlakuan yang dapat dijadikan sebagai teknik pengubahan tingkah laku seks bebas dan homoseks. Data dikumpulkan melalui dokumen teks pemikiran Ibnu Qoyyim al-Jauziyyah, observasi dan interviu subjek terteliti lapangan. Penelitian menggunakan pendekatan kualitatif dengan analisis hermeneutika bersusun. Hasil penelitian adalah (1 sasaran intervensi pengubahan tingkah laku berfokus di pengubahan pikiran/keyakinan; (2 analisis dan diagnosis berkisar pada pikiran/keyakinan dan kebiasaan/perbuatan yang tidak sehat; (3 ditemukan bentuk perlakuan dalam pengentasan korban seks bebas dan homoseks berupa teknik intervensi pikiran, teknik pengentasan gangguan syahwat, teknik

  19. 77 FR 10649 - Modification of Class E Airspace; Douglas, AZ

    Science.gov (United States)

    2012-02-23

    ...-1313; Airspace Docket No. 11-AWP-17] Modification of Class E Airspace; Douglas, AZ AGENCY: Federal... Bisbee Douglas International Airport, Douglas, AZ. Decommissioning of the Cochise VHF Omni-Directional... Federal Register a notice of proposed rulemaking to amend controlled airspace at Douglas, AZ (76 FR 78180...

  20. ANALISIS WAKTU PEMUPUKAN TANAMAN SAWI HIJAU (Brassica rapa var. parachinensis DENGAN TEKNIK PERUNUT RADIOAKTIF

    Directory of Open Access Journals (Sweden)

    Gusti Ngurah Sutapa

    2016-11-01

    Full Text Available Telah dilakukan penelitian analisis waktu pemupukan pada tanaman sawi hijau (Brassica rapa var. parachinensisdengan teknik perunut radioaktif. Untuk menuju sistem pertanian berkelanjutan perlu adanya perbaikan pertanian(intensifikasi selama beberapa tahun yang lalu masih signifikan, karena ketersediaan sumber daya alam danteknologi pertanian cukup memadai dan berimbang dengan ketersediaan lahan dan peningkatan jumlah penduduk.Keadaan ini sulit untuk dipertahankan dimasa yang akan datang, kecuali ada pendekatan baru yang menawarkan ide dan teknik untuk meningkatkan produktifitas pertanian. Efesiensi pemupukan tanaman dengan teknik perunut (tracer radioisotop adalah salah satu potensi menujusistem pertanian berkelanjutan. Teknik perunut dapat digunakan antara lain untuk mempelajari hubungan antaratanah dan tanaman, menentukan kondisi optimal dalam penggunaan pupuk (waktu pemupukan, pola perakaranaktif tanaman, jenis dan takaran pupuk, mempelajari proses dekomposisi dan mineralisasi bahan organik, sertamempelajari proses fotosintesis tanaman,baik dengan metoda langsung maupun tidak langsung.Waktu pemupukanyang lebih tepat dapat ditentukan dengan teknik perunut tersebut, sehingga optimalisasi pemupukan dapat dicapai,tanpa pemborosan yang tidak berguna.Dari penelitian dengan menggunakan radioisotop P, ternyata waktupemupukan pada tanaman sawi hijau (Brassica rapa var. parachinensis yang paling signifikan adalah padapukul 9.00 pagi. Waktu siang hari mulai pukul 11.00 sampai pukul 15.00 adalah waktu pemupukan yang sangatburuk. Sedangkan waktu sore hari yaitu pukul 15.00 sampai 17.00 menunjukkan waktu pemupukan yang semakinbaik namun tidak signifikan.32

  1. ANALISIS WAKTU PEMUPUKAN TANAMAN SAWI HIJAU (Brassica rapa var. parachinensis DENGAN TEKNIK PERUNUT RADIOAKTIF

    Directory of Open Access Journals (Sweden)

    Gusti Ngurah Sutapa

    2016-06-01

    Full Text Available Telah dilakukan penelitian analisis waktu pemupukan pada tanaman sawi hijau (Brassica rapa var. parachinensisdengan teknik perunut radioaktif. Untuk menuju sistem pertanian berkelanjutan perlu adanya perbaikan pertanian(intensifikasi selama beberapa tahun yang lalu masih signifikan, karena ketersediaan sumber daya alam danteknologi pertanian cukup memadai dan berimbang dengan ketersediaan lahan dan peningkatan jumlah penduduk.Keadaan ini sulit untuk dipertahankan dimasa yang akan datang, kecuali ada pendekatan baru yang menawarkan ide dan teknik untuk meningkatkan produktifitas pertanian. Efesiensi pemupukan tanaman dengan teknik perunut (tracer radioisotop adalah salah satu potensi menujusistem pertanian berkelanjutan. Teknik perunut dapat digunakan antara lain untuk mempelajari hubungan antaratanah dan tanaman, menentukan kondisi optimal dalam penggunaan pupuk (waktu pemupukan, pola perakaranaktif tanaman, jenis dan takaran pupuk, mempelajari proses dekomposisi dan mineralisasi bahan organik, sertamempelajari proses fotosintesis tanaman,baik dengan metoda langsung maupun tidak langsung.Waktu pemupukanyang lebih tepat dapat ditentukan dengan teknik perunut tersebut, sehingga optimalisasi pemupukan dapat dicapai,tanpa pemborosan yang tidak berguna.Dari penelitian dengan menggunakan radioisotop P, ternyata waktupemupukan pada tanaman sawi hijau (Brassica rapa var. parachinensis yang paling signifikan adalah padapukul 9.00 pagi. Waktu siang hari mulai pukul 11.00 sampai pukul 15.00 adalah waktu pemupukan yang sangatburuk. Sedangkan waktu sore hari yaitu pukul 15.00 sampai 17.00 menunjukkan waktu pemupukan yang semakinbaik namun tidak signifikan.32

  2. Analisis Tata Kelola Teknologi Informasi Menggunakan Kerangka Kerja COBIT 4.1 pada Fakultas Teknik Undip

    Directory of Open Access Journals (Sweden)

    Arini Arumana

    2014-06-01

    Full Text Available Peran teknologi informasi dalam suatu instansi sudah tidak dapat dielakkan lagi, mengingat perkembangannya yang begitu pesat seiring berjalannya waktu. Namun masalah yang sering terjadi di instansi adalah penggunaan teknologi informasi yang kadang tidak sesuai dengan harapan. Oleh karena itu diperlukan tata kelola terhadap penggunaan teknologi informasi yang biasa disebut dengan IT Governance. Fakultas teknik UNDIP adalah salah satu fakultas yang dalam operasionalnya sangat mengandalkan teknologi informasi, baik dalam aktifitas belajar mengajar maupun dalam menjalankan operasional bisnis. Kondisi sekarang di Fakultas Teknik sendiri tidak terdapat suatu indikator yang dapat menyatakan bahwa kinerja TI yang berjalan telah sesuai dengan visi dan misi Fakultas Teknik, oleh karena itu perlu dilakukan analisis tata kelola teknologi informasi, guna mengetahui performa TI sekarang sesuai dengan yang diharapkan oleh managemen atau tidak. Hasil dari analisis ini berupa tingkat kematangan tata kelola TI yang mecerminkan kondisi tata kelola TI di Fakultas Teknik dengan mengacu pada maturity level yang disediakan kerangka kerja COBIT 4.1, yakni dari level 0 (non-existent sampai 5 (optimized. Berdasarkan analisis yang dilakukan, secara garis besar kondisi kematangan tata kelola TI Fakultas Teknik berada pada level 2 yakni repeatable but intuitive. Kondisi ini mengacu pada beberapa kelemahan dalam proses-proses TI yang berjalan, diantaranya penetapan dan dokumentasi tindakan, kebijakan dan prosedur yang minim, serta tidak tersedianya service level yang disetujui bersama.

  3. IMPLEMESTASI E-KRS PADA PROGRAM STUDI D4 TEKNIK INFORMATIKA

    Directory of Open Access Journals (Sweden)

    Chairul Fikri Ramadhan

    2016-08-01

    Full Text Available Seiring dengan kemajuan ilmu pengetahuan dan teknologi, komputer telah digunakan untuk berbagai keperluan dan menjadi bagian yang sangat penting untuk menunjang aktifitas maupun pekerjaan dalam segala hal. Pemanfaatan atau pengembangan sistem komputer ini sangat membantu pekerjaan seseorang termasuk dalam kegiatan akademik. Termasuk pula perguruan tinggi Politeknik Harapan Bersama Tegal, khususnya Program Studi D4 Teknik Informatika. Pada setiap perguruan tinggi tentunya memiliki system pengisian KRS sebagai syarat untuk mengambil matakuliah yang akan ditempuh disemester depan. Namun banyak perguruan tinggi yang masih menggunakan sistem pengisian KRS dengan cara manual termasuk pada Program Studi D4 Teknik Informatika Politeknik Harapan Bersama Tegal.Berdasarkan kondisi tersebut, maka diperlukan perencanaan sebagai langkah awal, menganalisis data yang diperlukan, merancang sistem yang ada menggunakan UML, serta penerapannya untuk mengimplementasikan  sebuah sistem E-KRS pada program studi D4 Teknik Informatika dengan tujuan untuk menghasilkan sebuah aplikasi E-KRS pada Program Studi D4 Teknik Informatika sehingga mempermudah mahasiswa dalam mengisi formulir KRS secara online. Sistem dirancang dan dibangun dengan menggunakan teknologi PHP serta Framework Code Igniter, Xampp sebagai web server, MySql sebagai database server. Dan Adobe Dreamweaver sebagai editor. Kata kunci: Tegal, E-KRS, Program Studi D4 Teknik Informatika

  4. Kain Songket Palembang dengan Penerapan Teknik Batik sebagai Produk Fesyen

    Directory of Open Access Journals (Sweden)

    Nadina Sukma Salim

    2016-06-01

    Full Text Available Minimnya perkembangan motif Songket Palembang dan menghadapi kemunculan ‘songket’ mesin yang harga jualnya jauh lebih murah membuat beberapa pengrajin tenun songket asli menggunakan material alternatif, seperti sutera campuran, benang emas campuran, dan lain-lain untuk tetap bertahan. Semaraknya tren batik di Indonesia sejak UNICEF menetapkan batik sebagai warisan tak benda asli Indonesia, namun banyak masyarakat dalam dan luar Palembang yang tidak kenal dengan Batik Palembang. Kenyataannya, karena ketidakpahaman ini dan karena sisi ekonomis menyebabkannya sebagian masyarakat terpaksa memilih tekstil hasil industri pabrik dibanding karya asli daerah. Akhirnya, kepentingan untuk mempopulerkan motif batik Palembang yang mulai terlupakan juga menjadi kepentingan penelitian ini, selain kebutuhan akan variasi baru kreasi kain Songket Palembang. Hubungan dengan Cina dan India memberikan pengaruh dalam beberapa ragam hias dan warna pada kain Songket Palembang. Kesultanan Palembang Darussalam membeli benang emas dari Cina untuk ditenun menghiasi Songket Palembang sebagai pakaian  mewah kalangan bangsawan wanita. Berdasarkan kuantitas benang dan motif yang diterapkan di dalamnya, kain songket berbeda bagi golongan penggunanya. Diketahui, sebagai komoditi dagang dari Jawa, batik juga dikenakan oleh masyarakat Palembang. Motif-motif tertentu digemari dan menjadi ciri khas motif Palembangan hingga kini. Batik Palembang tidak dibuat di Palembang melainkan di Pesisir Jawa. Oleh karena itu, motifnya merupakan paduan ragam hias flora fauna Palembang dan corak songket selain motif India dan daerah pembuatnya. Akhirnya, salah satu solusi yang ditawarkan untuk keragaman variasi ini adalah menerapkan teknik batik di atas permukaan kain Songket Palembang sebagai salah satu cara menghias permukaan kain. Penerapan ini dapat dilakukan karena kain terbuat dari benang sutera alam. Menggunakan mode kualitatif, data-data didapat melalui literatur, wawancara dan

  5. Rekayasa Biopolimer Jerami Padi dengan Teknik Kopolimerisasi Cangkok dan Taut Silang

    Directory of Open Access Journals (Sweden)

    Henny Purwaningsih

    2017-03-01

    Full Text Available Kopolimerisasi cangkok dan taut silang akrilamida (AAm terhadap jerami padi dilakukan dalamsuasana hampa udara menggunakan aliran gas N2 dengan amonium persulfat (APS sebagai inisiatordan N,N’-metilena-bis-akrilamida (MBAAm. Pencirian dilakukan dengan teknik mikroskopipemayaran elektron (SEM untuk melihat morfologi permukaan, teknik spektroskopi FTIR untukmelihat gugus fungsi, dan teknik DTA untuk menganalisis ketahanan produk terhadap suhu. Kajiandilakukan terhadap swelling capacity produk hasil rekayasa. Spektra FTIR dan mikrografmenunjukkan bahwa kopolimerisasi cangkok dan taut silang telah terjadi pada biopolimer selulosajerami padi. Produk hasil rekayasa memiliki ketahanan termal yang lebih baik dan indeks kristalinitasyang lebih tinggi dari isolat selulosanya. Nisbah dan efisiensi pencangkokan berturut-turut adalah66,14-78.15% dan 13,23-16.63%. Swelling capacity sebelum proses hidrolisis berkisar antara 8,16-12,20 g g-1. Proses hidrolisis terhadap produk hasil rekayasa mampu meningkatkan swelling capacityhingga 12,5 kali kapasitas awal.

  6. Tank 241-AZ-101 tank characterization plan

    International Nuclear Information System (INIS)

    Schreiber, R.D.

    1995-01-01

    The Defense Nuclear Facilities Safety Board has advised the DOE to concentrate the near-term sampling and analysis activities on identification and resolution of safety issues. The Data Quality Objective (DQO) process was chosen as a tool to be used in the resolution of safety issues. As a result, A revision in the Federal Facilities Agreement and Consent Order (Tri-Party Agreement) milestone M-44 has been made, which states that ''A Tank Characterization Plan (TCP) will also be developed for each double-shell tank (DST) and single-shell tank (SST) using the DQO process. Development of TCPs by the DQO process is intended to allow users to ensure their needs will be met and that resources are devoted to gaining only necessary information''. This document satisfies that requirement for Tank 241-AZ-101 (AZ-101) sampling activities. Tank AZ-101 is currently a non-Watch List tank, so the only DQOs applicable to this tank are the safety screening DQO and the compatibility DQO, as described below. The contents of Tank AZ-101, as of October 31, 1994, consisted of 3,630 kL (960 kgal) of dilute non-complexed waste and aging waste from PUREX (NCAW, neutralized current acid waste). Tank AZ-101 is expected to have two primary layers. The bottom layer is composed of 132 kL of sludge, and the top layer is composed of 3,500 kL of supernatant, with a total tank waste depth of approximately 8.87 meters

  7. Tank 241-AZ-102 tank characterization plan

    International Nuclear Information System (INIS)

    Schreiber, R.D.

    1995-01-01

    The Defense Nuclear Facilities Safety Board has advised the DOE to concentrate the near-term sampling and analysis activities on identification and resolution of safety issues. The Data Quality Objective (DQO) process was chosen as a tool to be used in the resolution of safety issues. As a result, a revision in the Federal Facilities Agreement and Consent Order (Tri-Party Agreement) milestone M-44 has been made, which states that ''A Tank Characterization Plan (TCP) will also be developed for each double-shell tank (DST) and single-shell tank (SST) using the DQO process ... Development of TCPs by the DQO process is intended to allow users to ensure their needs will be met and that resources are devoted to gaining only necessary information''. This document satisfies that requirement for tank 241-AZ-102 (AZ-102) sampling activities. Tank AZ-102 is currently a non-Watch List tank, so the only DQOs applicable to this tank are the safety screening DQO and the compatibility DQO, as described below. The current contents of Tank AZ-102, as of October 31, 1994, consisted of 3,600 kL (950 kgal) of dilute non-complexed waste and aging waste from PUREX (NCAW, neutralized current acid waste). Tank AZ-102 is expected to have two primary layers. The bottom layer is composed of 360 kL of sludge, and the top layer is composed of 3,240 kL of supernatant, with a total tank waste depth of approximately 8.9 meters

  8. Meningkatkan Minat Terhadap Jurusan Teknik Gambar Bangunan Melalui Layanan Bimbingan Kelompok

    Directory of Open Access Journals (Sweden)

    Faskhau Maulvi Alim

    2014-10-01

    Full Text Available Tujuan dari penelitian ini untuk mengetahui gambaran minat terhadap jurusan Teknik Gambar Bangunan sebelum dan setelah memperoleh layanan Bimbingan Kelompok serta mengetahui perbedaan tingkat minat terhadap jurusan Teknik Gambar Bangunan sebelum dan setelah memperoleh layanan Bimbingan Kelompok. Penelitian ini dilakukan di SMK Negeri 5 Semarang dengan subyek 10 orang siswa. Metode pengumpulan data yang digunakan yaitu skala psikologis. Teknik analisis data menggunakan uji wilcoxon match pairs. Hasil penelitian menunjukan minat terhadap jurusan Teknik Gambar Bangunan sebelum pemberian treatment rata-rata pada kategori sedang (67,9%. Setelah pemberian treatment, minat terhadap jurusan Teknik Gambar Bangunan rata-rata pada kategori tinggi (79,1%. Hasil uji wilcoxon match pairs menunjukan   (0 dan   5% (8, sehingga   (0   8 yang berarti   diterima dan   ditolak. Hal tersebut menunjukan bahwa minat terhadap jurusan Teknik Gambar Bangunan dapat ditingkatkan melalui layanan Bimbingan Kelompok. The research problems are include (1  How is the cooperative model type talking stick which is helped multimedia quiz creator to improve the senior high school students’ folklore attentive skill. (2 how is the principles of cooperative model type talking stick development which is helped by multimedia quiz creator to improve the  senior high school students’ folklore attentive skill. This research uses research and development design (R&D, this research developes model which  have been exist that is cooperative model type talking stick into cooperative model type talking stick which is helped by multimedia quiz creator. The results of the researches are : (1 the teacher and students’ need toward to cooperative model type talking stick which is helped by multimedia quiz creator. (2 cooperative model type talking stick priciples are (a innovative learning strategy, (b innovative learning media, (c assessment.

  9. MENINGKATKAN KEMAMPUAN KOMUNIKASI ANTAR PRIBADI MELALU BIMBINGAN KELOMPOK DENGAN TEKNIK PERMAINAN KERJASAMA PADA SISWA KELAS XI MATEMATIKA DAN SAINS 2 DI SMA NEGERI 1 MUNTILAN

    OpenAIRE

    Ardiatma Rio Respati

    2015-01-01

    Melalui Bimbingan Kelompok dengan teknik Permainan Kerjasama diharapkan rendahnya komunikasi antar pribadi siswa dapat ditingkatkan. Tujuan dari penelitian ini adalah untuk mengetahui keberhasilan dalam meningkatkan komunikasi antar pribadi melalui Bimbingan Kelompok dengan Teknik Permainan Kerjasama. Metode pengumpulan data menggunakan skala psikologi. Sedangkan teknik analisis data yang digunakan adalah statistik non parametrik dengan rumus wilcoxon. Dari hasil penelitian menunjukan komunik...

  10. PENGEMBANGAN TEKNIK TRITIK JUMPUTAN DENGAN SISTEM LIPAT IKAT DAN LIPAT JELUJUR

    Directory of Open Access Journals (Sweden)

    Suryawati Ristiani

    2016-06-01

    Full Text Available ABSTRAKTritik jumputan adalah proses pewarnaan rintang pada kain dengan menggunakan bahan perintang seperti tali, benang atau sejenisnya menurut corak-corak tertentu. Pada umumnya motif yang dihasilkan dari teknik tritik jumputan adalah bulat-bulat dan garis berupa motif  seperti biji mentimun berderet. Tujuan penelitian ini adalah mengembangkan teknik tritik jumputan sehingga menghasilkan motif selain bulat dan garis. Metode yang digunakan dalam  kegiatan ini  adalah  metode ujicoba  pengembangan tritik jumputan dengan teknik lipat ikat dan lipat jelujur. Hasil ujicoba dianalisa secara kualitatif dengan pengamatan visual dan uji kesukaan. Analisa kuantitatif dilakukan melalui uji laboratorium dan uji kesukaan berdasarkan pengukuran Likert dengan skala 5. Kegiatan ini menghasilkan enam belas teknik lipat tritik jumputan yang terdiri dari sembilan teknik lipat ikat dan tujuh teknik lipat jelujur. Hasil pengujian ketahanan luntur warna terhadap pencucian, keringat, cahaya, dan penekanan panas pada kain warna sintetis maupun alam menunjukkan rata-rata 4-5 (baik. Hasil pengujian ketahanan luntur warna terhadap gosokan menunjukkan  rata-rata  3-4 (cukup baik. Hasil uji kesukaan terhadap 10 sampel produk jumputan teknik lipat, menunjukkan bahwa rata-rata responden menilai bagus, dengan nilai rata-rata 116,4.Kata kunci: Teknik lipat, kain, pewarnaan, tritik jumputan ABSTRACT Tritik jumputan is resist dyeing technique on textiles by using rope, yarn or others as resisting materials, following certain motifs. The most common motifs of tritik jumputan are circles and lines, such as a row of cucumber seeds. The purpose of this research is to develop tritik jumputan techniques to produce motif other than circles and lines. The method of this research is experimental exploration of tritik Jumputan motif with folded tie and folded hem technique. The results are analyzed qualitatively by visual observation, being watched with eyes (observe and

  11. Friction welding of AZ31 magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Tsujino, R.; Ochi, H. [Osaka Inst. of Tech., Osaka (Japan); Kawai, G. [Osaka Sangyo Univ., Osaka (Japan); Yamaguchi, H.; Ogawa, K. [Osaka Prefecture Univ., Osaka (Japan); Suga, Y. [Keio Univ., Kanagawa (Japan)

    2003-07-01

    In this paper, for an acceleration of utilization of magnesium alloy which is being interested in recent years, friction welding of AZ31 magnesium alloy was carried out, and the joint performance was discussed in relation to the deformation heat input in the upset stage and upset loss as a evaluation factor. Where, the deformation heat input in the upset stage is mechanical work represented by the product of upset speed and axial pressure. As a result, it was made clear that the friction welding of AZ31 magnesium alloy was easy in the atmosphere, and good welded joints without a non- adhesion area at the weld interface could de obtained. Moreover, the evaluation factors discussed were possible to evaluate to joint performance. (orig.)

  12. SISTEM INFORMASI RENSTRA DAN RENOP JURUSAN TEKNIK ELEKTRO POLITEKNIK NEGERI SEMARANG

    Directory of Open Access Journals (Sweden)

    Alifia Choirunnisa

    2016-10-01

    Full Text Available Setiap jurusan di Politeknik Negeri Semarang mempunyai Rencana Strategi (Renstra dan Rencana Operasional (Renop untuk mengelola dan memantau perkembangan jurusannya masing-masing. Salah satu jurusannya yaitu jurusan Teknik Elektro. Dalam pengelolaan data perencanaan strategi dan operasional jurusan Teknik Elektro masih dilakukan secara manual. Dengan memanfaatkan teknologi sistem informasi, Sistem Informasi Renstra dan Renop Jurusan Teknik Elektro Berbasis Web mengubah sistem pengelolaan dari manual menjadi berbasis teknologi sistem informasi yang lebih efisien dan efektif. Tujuan dari pembuatan sistem informasi ini adalah untuk menghasilkan sebuah Sistem Informasi Renstra dan Renop Jurusan Teknik Elektro Berbasis Web serta membantu dan memberikan kemudahan dalam pengelolaan informasi Renstra dan Renop. Metode yang digunakan dalam penelitian ini adalah metodologi waterfall, dimana dalam metodologi ini setiap langkah penelitian dilakukan secara berurutan, mulai dari tahapan Analisis Kebutuhan, Desain Sistem, Implementasi dan Pengujian Unit, Integrasi dan Pengujian Sistem, serta Operasi dan Pemeliharaan. Perancangan sistem menggunakan model Data Flow Diagram (DFD. Pembangunan sistem menggunakan bahasa pemrograman PHP dan framework codeigniter serta database MySQL. Pengujian sistem menggunakan metode pengujian setiap unit fungsi dari masing-masing fitur. Hasil dari penelitian ini yaitu sebuah sistem informasi yang dapat membantu ketua jurusan, sekretaris jurusan, maupun ketua program studi dalam mengelola Renstra dan Renop. Sistem ini telah di uji coba dengan hasil tingkat kepuasan pengguna sebesar 81,2%.

  13. KEEFEKTIFAN TEKNIK SELF-INSTRUCTION UNTUK MENINGKATKAN KEPERCAYAAN DIRI SISWA SMP

    Directory of Open Access Journals (Sweden)

    Kasa Fiorentika

    2016-09-01

    Full Text Available ABSTRACT : The aim of this study was to determine the effectiveness of self -instruction techniques to increase the confidence of the students of SMPN 20 Malang . Data were collected using the inventory of confidence and analyzed with the Wilcoxon test through SPSS to students who have low self-esteem category . Results from the study are students who have a low level of confidence there are five people , students were given counseling group with the techniques of self -instruction , students are given a pretest - posttest to measure the effectiveness of a given technique , students increase confidence after attending group counseling techniques self- instruction . ABSTRAK: Tujuan dari penelitian ini adalah untuk mengetahui keefektifan teknik self-instruction untuk meningkatkan kepercayaan diri siswa SMPN 20 Malang. Data dikumpulkan menggunakan inventori kepercayaan diri dan dianalisis  dengan uji wilcoxon melalui SPSS  kepada siswa yang mempunyai kategori kepercayaan diri rendah. Hasil dari penelitian adalah siswa yang mempunyai tingkat kepercayaan diri rendah ada lima orang, siswa diberikan konseling kelompok dengan teknik self-instruction, siswa diberikan pretest-posttest untuk mengukur keefektifan teknik yang diberikan, siswa mengalami peningkatan kepercayaan diri setelah mengikuti konseling kelompok dengan teknik self-instruction.

  14. Layanan Bimbingan Kelompok Teknik Sosiodrama Untuk Meningkatkan Karakter Cinta Damai Siswa

    Directory of Open Access Journals (Sweden)

    Dwiana Kartikawati

    2018-03-01

    Full Text Available Abstrak Tujuan dari penelitian ini adalah untuk mengetahui keefektifan layanan bimbingan kelompok teknik sosiodrama dalam meningkatkan karakter cinta damai pada siswa. Penelitian ini memiliki dua variabel, yaitu variabel terikat karakter cinta damai (Y, variabel bebas bimbingan kelompok teknik sosiodrama (X. Jenis penelitian yang digunakan adalah penelitian eksperimen. Sampel penelitian ini adalah 12 siswa kelas VII B SMP Negeri 1 Tambak, Banyumas dan teknik pengambilan sampel yang digunakan adalah teknik purposive sampling. Metode pengumpulan data menggunakan skala psikologis dan observasi. Sedangkan alat pengumpul datanya menggunakan skala cinta damai dan daftar pelanggaran siswa. Teknik analisis data yang digunakan analisis deskriptif persentase dan Wilcoxon Match Pairs Test. Dari analisis Wilcoxon diperoleh Zhitung = (-3,065 dan Ztabel adalah (14, jadi Zhitung (-3,065 < Ztabel (14. Dapat disimpulkan ada perbedaan yang signifikan mengenai karakter cinta damai siswa sebelum dan setelah mendapat layanan bimbingan kelompok teknik sosiodrama Dengan demikian teruji bahwa layanan bimbingan kelompok teknik sosiodrama efektif dalam meningkatkan karakter cinta damai pada siswa. Abstract The purpose of this research is to know the effectiveness of the group counceling service in sosiodrama technique to improve the students’ love peaceful character. This research has two variabel, there are variabel that tie on love peaceful character (Y, free variabel of  group counceling service in sosiodrama technique (X. The kind of research that use is experimental research. The sample of this research are 12 students in class VII B at SMP Negeri 1 Tambak, Banyumas and the technique to get the sample is use purposive sampling technique. The method to collect the data is use psychology method and oberservation. Whereas, the instrument to collect the data is use love peaceful scale and list of violations of the students. The data analysis technique that use are

  15. Teknik Pewarnaan Agel dengan Zat Warna Alam dari Daun Jati

    Directory of Open Access Journals (Sweden)

    Eustasia Sri Murwati

    2011-04-01

    Full Text Available ABSTRAKAgel (Corypha gebanga BL merupakan jenis tanaman yang banyak tumbuh di Indonesia dan telah dimanfaatkan oleh para perajin untuk dibuat menjadi berbagai jenis barang kerajinan bernilai ekonomis. Namun proses pewarnaan yang sering digunakan selama ini adalah pewarnaan menggunakan zat warna sintetis yang kurang ramah lingkungan. Hal ini terjadi karena masih banyak kendala dalam pewarnaan alam, salah satunya adalah warna yang didapatkan menjadi kusam. Untuk itu diperlukan penelitian teknik pewarnaan yang tepat untuk memperoleh hasil yang optimal. Daun jati dipilih menjadi bahan dasar zat warna alam karena jumlah yang melimpah di Indonesia, regenerasi yang cukup cepat dibandingkan bahan pewarna alam dari kayu, dan termasuk jenis zat warna yang memiliki afinitas besar terhadap serat selulose. Penelitian ini bertujuan memperoleh suhu, lama perendaman, dan proses mordan yang tepat untuk pewarnaan agel dengan zat warna alam dari daun jati. Metoda eksperimental dengan tahapan; penelitian bahan baku, uji kekuatan tarik sebelum dan sesudah diwarna, diproses mordan, diwarna dengan variasi suhu (60°C, 80°C, 100°C dan waktu pencelupan 30 menit, pengujian (ketahanan luntur warna terhadap cuci, gosok, dan sinar matahari, dan ketuaan warna. Hasil pengujian ketuaan warna pada suhu 100°C didapatkan warna paling tua (penyerapan optimal dengan %T (Transmitansi terkecil, suhu 80°C %T lebih tinggi dari pada suhu 100°C, dan pada suhu 60° C %T memiliki nilai tertinggi dengan warna kurang tua. Hasil pengujian ketahanan luntur warna terhadap cuci,gosok, dan sinar matahari baik. Sesudah pewarnaan tidak menurunkan kekuatan tarik.Kata kunci: agel, daun jati, ketuaan warna, suhu,warna alamABSTRACTAgel (Corypha gebanga BL grow widely in Indonesia and has been used by craftmen as material for various kinds of valuable handicrafts. However the coloring process of agel still use the staining with synthetic dyes that are less environmentally friendly. It is caused by

  16. Meningkatkan Kedisiplinan Belajar Siswa Melalui Layanan Penguasaan Konten dengan Teknik Modelling

    Directory of Open Access Journals (Sweden)

    Khuliyah Khuliyah

    2014-10-01

    Full Text Available Tujuan penelitian ini untuk mengetahui peningkatan kedisiplinan belajar siswa setelah diberikan layanan penguasaan konten dengan  teknik modelling. Jenis penelitian ini adalah penelitian tindakan kelas. Subjek dalam penelitian ini yaitu siswa kelass VII H SMP Negeri 3 Ungaran yang berjumlah 31 siswa. Teknik pengumpulan data menggunakan skala kedisiplinan belajar dan pedoman observasi. Instrumen tersebut telah diujicobakan untuk digunakan dalam penelitian menggunakan validitas dengan rumus product moment oleh Pearson dan reliabilitas instrumen dengan rumus alpha. Teknik analisis data yang digunakan yakni analisis deskriptif persentase dan Uji t (t-test. Hasil penelitian ini menunjukkan bahwa terdapat peningkatan kedisiplinan belajar siswa melalui layanan penguasaan konten dengan teknik modelling, dengan nilai  >  yaitu 16,874 > 2,042. Simpulan dari penelitian ini adalah kedisiplinan belajar siswa dapat ditingkatkan melalui layanan penguasaan konten dengan teknik modelling. Oleh karena itu, diharapkan guru pembimbing dapat meningkatkan layanan penguasaan konten kepada siswa sebagai strategi untuk membantu siswa dalam meningkatkan kedisiplinan belajar. The purpose of this study is to identify the improvement of learning discipline of student after given mastery of content service by modeling technique. Subjects of this study are students of class VII H in SMP Negeri 3 Ungaran which involved 31 students. Data collection techniques were using the learning discipline scale and observation. Validity of instrument has been tested using Pearson product moment and reliability of the instrument with alpha formula. Data analysis technique used percentage descriptive analysis and t-test (t–test. The results of this study indicate that there is an increase of student learning discipline through the mastery of content services with modeling technique, the value of  >  is 16.874 > 2.042. From this research it can be concluded that student learning

  17. Meningkatkan Kematangan Emosi Melalui Layanan Penguasaan Konten dengan Teknik Bermain (Games

    Directory of Open Access Journals (Sweden)

    Miftakhatun Riza

    2014-06-01

    Full Text Available Tujuan penelitian ini untuk memperoleh informasi atau temuan empiris tentang meningkatkan kematangan emosi melalui layanan penguasaan konten dengan teknik bermain (games pada siswa kelas IV SD N 01 Sijambe. Jenis penelitian yang digunakan dalam penelitian ini adalah penelitian quasi eksperimen. Subyek penelitian dalam penelitian ini adalah siswa kelas IV di SD N 01 Sijambe yang berjumlah 33 siswa. Teknik pengumpulan data menggunakan skala kematangan emosi. Instrumen tersebut telah diujicobakan untuk digunakan dalam penelitian menggunakan validitas dengan rumus product moment oleh Pearson dan reabilitas instrument dengan rumus Alpha. Teknik analisis data yang digunakan yakni analisis deskriptif persentase dan Uji beda t-Test. Hasil penelitian ini menunjukan bahwa terjadi peningkatan kematangan emosi melalui layanan penguasaan konten dengan teknik bermain (games, dengan nilai thitung = 15,064 >  ttabel = 2,038.  Simpulan dari penelitian ini yakni kematangan emosi dapat ditingkatkan melalui layanan penguasaan konten dengan teknik bermain (games. The purpose of this research is to get information or empirical finding about increase the emotional maturity, through mastery of content service with games technique to the fourth grade students class of SD N 01 Sijambe. This study is quasi-experimental. Subjects in this research were 33 students in grade IV of SD N 01 Sijambe. Data collection techniques using emotional maturity scale. The instrument has been tested for validity using Pearson product moment and reliability of the instrument with alpha formula. Data analysis used descriptive percentage, and t-Test. The result of study showed there was increase of emotional maturity through mastery of content service with games technique with rcount=15,064>rtable=2,038. The conclusion of study was emotional maturity could be increased through mastery of content service with games technique.

  18. MENINGKATKAN KEMATANGAN EMOSI MELALUI LAYANAN PENGUASAAN KONTEN DENGAN TEKNIK BERMAIN (GAMES

    Directory of Open Access Journals (Sweden)

    Miftakhatun Riza

    2014-06-01

    Full Text Available Tujuan penelitian ini untuk memperoleh informasi atau temuan empiris tentang meningkatkan kematangan emosi melalui layanan penguasaan konten dengan teknik bermain (games pada siswa kelas IV SD N 01 Sijambe. Jenis penelitian yang digunakan dalam penelitian ini adalah penelitian quasi eksperimen. Subyek penelitian dalam penelitian ini adalah siswa kelas IV di SD N 01 Sijambe yang berjumlah 33 siswa. Teknik pengumpulan data menggunakan skala kematangan emosi. Instrumen tersebut telah diujicobakan untuk digunakan dalam penelitian menggunakan validitas dengan rumus product moment oleh Pearson dan reabilitas instrument dengan rumus Alpha. Teknik analisis data yang digunakan yakni analisis deskriptif persentase dan Uji beda t-Test. Hasil penelitian ini menunjukan bahwa terjadi peningkatan kematangan emosi melalui layanan penguasaan konten dengan teknik bermain (games, dengan nilai thitung = 15,064 >  ttabel = 2,038.  Simpulan dari penelitian ini yakni kematangan emosi dapat ditingkatkan melalui layanan penguasaan konten dengan teknik bermain (games. The purpose of this research is to get information or empirical finding about increase the emotional maturity, through mastery of content service with games technique to the fourth grade students class of SD N 01 Sijambe. This study is quasi-experimental. Subjects in this research were 33 students in grade IV of SD N 01 Sijambe. Data collection techniques using emotional maturity scale. The instrument has been tested for validity using Pearson product moment and reliability of the instrument with alpha formula. Data analysis used descriptive percentage, and t-Test. The result of study showed there was increase of emotional maturity through mastery of content service with games technique with rcount=15,064>rtable=2,038. The conclusion of study was emotional maturity could be increased through mastery of content service with games technique.

  19. Meningkatkan Tanggung Jawab Belajar dengan Layanan Konseling Individual Teknik Self-Management

    Directory of Open Access Journals (Sweden)

    Dinia Ulfa

    2015-06-01

    Full Text Available Tujuan penelitian ini adalah untuk memperoleh data empiris tentang peningkatan tanggung jawab belajar melalui layanan konseling individual teknik self-management pada siswa kelas XI SMK Negeri 1 Pemalang. Populasinya adalah siswa  kelas XI Akuntasi 2 yang berjumlah 34 siswa dan sampel yang berjumlah 6 siswa menggunakan purposive sampling. Teknik pengumpulan data menggunakan skala tanggung jawab belajar. Instrumen tersebut telah diuji validitasnya dengan rumus product moment, sedangkan reliabilitas instrumen digunakan rumus Alpha.Teknik analisis data yang digunakan meliputi analisis deskriptif persentase, sedangkan untuk uji hipotesis menggunakan uji Wilcoxon dengan hasil perhitungan Zhitung = 2.20 > Ztabel = 0 pada n= 6, dengan taraf signifikansi 5%. Simpulan penelitian ini yaitu tanggung jawab belajar dapat ditingkatkan melalui layanan konseling individual teknik self-management.Oleh karena itu diharapkan guru pembimbing dapat lebih mengintensifkan layanan konseling individual teknik self-management sebagai strategi alternatif untuk membantu siswa meningkatkan tanggung jawab belajar. The aim of this research is to obtain the empirical data about the improvement of  learning responsibility through self-management technique individual counseling service. The population of this study were students of class XI Accounting 2 which consisted of 34 students. Puposive sampling technique was used to select 6 students as sample. The data collection technique used was learning responsibility scale. The instrument has been tested it’s validity with product moment formula, and reliability of the instrument with Alpha formula. Data analysis technique used were descriptive percentage and Wilcoxon test. The result of this research showed that there was improvement of learning responsibility through self-management technique  individual counseling service with Zcount = 2.20> Ztable = 0, n=6, with 5%  significance level. It could be concluded that learning

  20. Corrosion product layers on magnesium alloys AZ31 and AZ61: Surface chemistry and protective ability

    Science.gov (United States)

    Feliu, S.; Llorente, I.

    2015-08-01

    This paper studies the chemical composition of the corrosion product layers formed on magnesium alloys AZ31 and AZ61 following immersion in 0.6 M NaCl, with a view to better understanding their protective action. Relative differences in the chemical nature of the layers were quantified by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDX) and low-angle X-ray diffraction (XRD). Corrosion behavior was investigated by Electrochemical Impedance Spectroscopy (EIS) and hydrogen evolution measurement. An inhibitive effect from the corrosion product layers was observed from EIS, principally in the case of AZ31, as confirmed by hydrogen evolution tests. A link was found between carbonate enrichment observed by XPS in the surface of the corrosion product layer, concomitant with the increase in the protective properties observed by EIS.

  1. Mengembangkan Kemampuan Manajemen Waktu Melalui Layanan Penguasaan Konten dengan Teknik Kontrak Perilaku

    Directory of Open Access Journals (Sweden)

    Anisa Puji Harlina

    2014-06-01

    Full Text Available Tujuan penelitian ini untuk memperoleh informasi atau temuan empiris tentang mengembangkan kemampuan manajemen waktu melalui layanan penguasaan konten dengan teknik kontrak perilaku pada siswa kelas VIII B SMP N 21 Semarang. Populasinya adalah seluruh  kelas VIII SMP N 21 Semarang yang berjumlah 224 siswa dan sampel yang berjumlah 28 siswa menggunakan purposeive sampling. Teknik pengumpulan data menggunakan kuesioner manajemen waktu. Instrumen tersebut telah diujicobakan untuk digunakan dalam penelitian menggunakan validitas dengan rumus product moment oleh Pearson dan reabilitas instrument dengan rumus Alpha. Teknik analisis data yang digunakan yakni analisis deskriptif persentase dan Uji t ( t-test. Hasil penelitian ini menunjukan bahwa terdapat perkembangan kemampuan manajemen waktu melalui layanan penguasaan konten dengan teknik kontrak perilaku, dengan nilai rhitung = 20,64 > rtabel = 2,052. Simpulan dari penelitian ini yakni kemampuan manajemen waktu dapat dikembangkan melalui layanan penguasaan konten dengan teknik kontrak perilaku. Oleh karena itu, diharapkan guru pembimbing dapat lebih mengintensifkan layanan penguasaan konten dengan teknik kontrak perilaku kepada siswa sebagai strategi alternative untuk membantu siswa mengembangkan kemampuan manajemen waktu. The purpose of the study was to get information or empirical finding about developing the skill of time management, through mastery of content service with behavior contract technique to the eighth grade students B class of SMP N 21 Semarang. The population was all student of the VIII B class in SMP N 21 Semarang, which consenst of  244 students  Purposive sampling technique was used in this study, samples were 28 students. Data collection techniques using time management questionnaire. The instrument has been tested for validity using Pearson product moment and reliability of the instrument with alpha formula. Data collecting technique using quesionnaire in form of time

  2. Joining of AZ31 and AZ91 Mg alloys by friction stir welding

    Directory of Open Access Journals (Sweden)

    B. Ratna Sunil

    2015-12-01

    Full Text Available Two dissimilar magnesium (Mg alloy sheets, one with low aluminium (AZ31 and another with high aluminium (AZ91 content, were successfully joined by friction stir welding (FSW. The effect of process parameters on the formation of hot cracks was investigated. A sound metallurgical joint was obtained at optimized process parameters (1400 rpm with 25 mm/min feed which contained fine grains and distributed β (Mg17Al12 phase within the nugget zone. An increasing trend in the hardness measurements has also confirmed more amount of dissolution of aluminium within the nugget zone. A sharp interface between nugget zone and thermo mechanical affected zone (TMAZ was clearly noticed at the AZ31 Mg alloy side (advancing but not on the AZ91 Mg alloy side (retreating. From the results it can be concluded that FSW can be effectively used to join dissimilar metals, particularly difficult to process metals such as Mg alloys, and hot cracking can be completely eliminated by choosing appropriate process parameters to achieve sound joint.

  3. Tank 241-AZ-101 and tank 241-AZ-102, airlift circulator operation vapor sampling and analysis plan

    International Nuclear Information System (INIS)

    TEMPLETON, A.M.

    1999-01-01

    This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for vapor samples obtained during the operation of the tank 241-AZ-101 and 241-AZ-102 airlift circulators (ALCs). The purpose of the ALC operation is to support portions of the operational test procedure (OTP) for Project W-030 (OTP-W030-001) and to perform functional test in support of Project W-151. Project W-030 is the 241-A-702 ventilation upgrade project (241-AZ-702) and Project W-151 is the 241-AZ-101 Mixer Pump Test. The functional tests will check the operability of the tank 241-AZ-101 ALCs. Process Memo's No.2E98-082 and No.2E99-001 (LMHC 1999a, LMHC 1999b) direct the operation of the ALCs and the Industrial Hygiene monitoring respectively. A series of tests will be conducted in which the ALCs in tanks 241-AZ-101 and 241-AZ-102 will be operated at different air flow rates. Vapor samples will be obtained to determine constituents that may be present in the tank headspace during ALC operation at tanks 241-AZ-101 and 241-AZ-102 as the waste is disturbed. During the testing, vapor samples will be obtained from the headspace of tanks 241-AZ-101 and 241-AZ-102 via the unused port on the standard hydrogen monitoring system (SHMS). Results will be used to provide the waste feed delivery program with environmental air permitting data for tank waste disturbing activities. Because of radiological concerns, the samples will be filtered for particulates. It is recognized that this may remove some organic compounds

  4. Grain refinement of AZ31 magnesium alloy by electromagnetic ...

    Indian Academy of Sciences (India)

    Low-frequency electromagnetic field; AZ31 magnesium alloy; Al4C3; grain refinement. Abstract. The effects of electromagnetic stirring and Al4C3 grain refiner on the grain refinement of semicontinuously cast AZ31 magnesium alloy were discussed in this investigation. The results indicate that electromagnetic stirring has an ...

  5. ANALYSIS RESULTS FOR BUILDING 241 702-AZ A TRAIN

    Energy Technology Data Exchange (ETDEWEB)

    DUNCAN JB; FRYE JM; COOKE CA; LI SW; BROCKMAN FJ

    2006-12-13

    This report presents the analyses results for three samples obtained under RPP-PLAN-28509, Sampling and Analysis Plan for Building 241 702-AZ A Train. The sampling and analysis was done in response to problem evaluation request number PER-2004-6139, 702-AZ Filter Rooms Need Radiological Cleanup Efforts.

  6. 76 FR 18378 - Amendment of Class E Airspace; Taylor, AZ

    Science.gov (United States)

    2011-04-04

    ...-1189; Airspace Docket No. 10-AWP-19] Amendment of Class E Airspace; Taylor, AZ AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Final rule. SUMMARY: This action will amend Class E airspace at Taylor Airport, Taylor, AZ, to accommodate aircraft using the CAMBO One Departure, and the Area Navigation (RNAV...

  7. ANALYSIS RESULTS FOR BUILDING 241 702-AZ A TRAIN

    International Nuclear Information System (INIS)

    DUNCAN JB; FRYE JM; COOKE CA; LI SW; BROCKMAN FJ

    2006-01-01

    This report presents the analyses results for three samples obtained under RPP-PLAN-28509, Sampling and Analysis Plan for Building 241 702-AZ A Train. The sampling and analysis was done in response to problem evaluation request number PER-2004-6139, 702-AZ Filter Rooms Need Radiological Cleanup Efforts

  8. 702AZ aging waste ventilation facility year 2000 test procedure

    International Nuclear Information System (INIS)

    Winkelman, W.D.

    1998-01-01

    This test procedure was developed to determine if the 702AZ Tank Ventilation Facility system is Year 2000 Compliant. The procedure provides detailed instructions for performing the operations necessary and documenting the results. This verification procedure will document that the 702AZ Facility Systems are year 2000 compliant and will correctly meet the criteria established in this procedure

  9. SURVEI TEKNIK CLUSTERING ROUTING BERDASARKAN MOBILITAS PADA WIRELESS AD-HOC NETWORK

    Directory of Open Access Journals (Sweden)

    I Nyoman Trisna Wirawan

    2016-01-01

    Full Text Available Wireless ad-hoc merupakan sebuah skema jaringan yang didesain supaya mampu beroperasi tanpa membutuhkan infrastruktur tetap serta bersifat otonom. Teknik flooding pada proses path discovery dalam kasus wireless ad-hoc network dapat menimbulkan masalah beban jaringan yang berlebihan. Oleh karena itu, sebuah skema clustering diusulkan untuk mengurangi adanya flooding paket yang berlebihan dengan membagi node-node dalam jaringan menjadi beberapa bagian berdasarkan parameter tertentu. Teknik ini efektifuntuk mengurangi paket yang harus dilewatkan dalam jaringan. Namun masalah muncul ketika sebuah jaringan wireless ad-hoc harus membentuk sebuah cluster dengan mempertimbangkan beberapa parameter khusus. Parameter tersebut harus disesuaikan dengan kasus yang dihadapi. Pada tulisan ini akan dibahas secara khusus mengenai penerapan skema clustering dalam lingkungan wireless ad-hoc network, baik pada MANETdan penyesuaian skema clustering yang harus dilakukan pada VANET berdasarkan mobilitasnya.

  10. Meningkatkan Kepercayaan Diri Remaja Putri Melalui Layanan Penguasaan Konten Teknik Role Playing

    Directory of Open Access Journals (Sweden)

    Nur Ida Farida

    2014-06-01

    Full Text Available Tujuan penelitian ini untuk mengetahui peningkatan kepercayaan diri remaja putri pubertas awal setelah diberikan layanan penguasaan konten dengan teknik role playing. Jenis penelitian ini adalah penelitian pre eksperimen. Populasinya remaja putri pubertas awal kelas VII SMP N 13 Semarang. Teknik sampling yang digunakan purposive sampling, dengan sampel 16 remaja putri pubertas awal yang memiliki kecenderungan kepercayaan diri rendah. Metode pengumpulan data menggunakan skala psikologi berupa skala kepercayaan diri. Analisis datanya  menggunakan uji wilcoxon match pair dan deskriptif persentase. Hasil penelitian ini menunjukkan bahwa layanan penguasaan konten dengan teknik role playing dapat meningkatkan kepercayaan diri remaja putri pubertas awal, dengan nilai zhitung = 0 < ztabel = 30. Simpulan dari penelitian ini yakni terdapat peningkatan kepercayaan diri remaja putri pubertas awal setelah diberikan layanan penguasaan konten dengan teknik role playing. This study seeks to find out the increasing confidence of female adolescent in early  puberty  after getting mastery content counseling by role playing technique. This research was using pre-experimental design with  female adolescents of seven graders in SMP N 13 Semarang as the  population. Purposive sampling technique was used  in this study. Sixteen adolescents in their early puberty that had tendency of  low self confidence was used as sample. Method for collecting data was used self confident scale; whereas, the data analysis used wilcoxon match pair test and descriptive percentage. The result of this study showed that counseling of mastery content by role playing technique was able to increase self confidence of female adolescent in early puberity with the score zcount = 0 < ztable= 30. It can concluded that there was increasing of self confidence for female adolescent in early puberty after getting counseling of mastery content by role playing.

  11. Implementasi dan Analisis Teknik Reduksi PAPR OFDM Menggunakan Metode PTS pada WARP

    Directory of Open Access Journals (Sweden)

    Rizkha Ajeng Rochmatika

    2017-01-01

    Full Text Available Sistem OFDM cocok digunakan sebagai solusi yang dapat memenuhi layanan komunikasi data kecepatan tinggi karena memiliki efisiensi bandwidth dengan performansi terbaik. Namun dalam implementasinya, sistem OFDM memiliki kelemahan yang disebabkan oleh tingginya nilai Peak to Average Power Ratio (PAPR sehingga sinyal OFDM rentan terkena distorsi nonlinear yang disebabkan oleh adanya komponen RF power amplifier yang menyebabkan kompleksitas komponen Analog to Digital Converter (ADC yang terdapat pada Wireless Open Access Research Platform (WARP. Nilai PAPR yang besar pada OFDM membutuhkan power amplifier dengan dynamic range yang lebar untuk mengakomodasi sinyal, apabila hal tersebut tidak terpenuhi maka menyebabkan distorsi nonlinear dan pada akhirnya menurunkan performansi OFDM. Oleh karena itu, untuk mengatasinya dibutuhkan suatu metode yang dapat mereduksi nilai PAPR salah satunya menggunakan metode PTS. Guna melihat unjuk kerja teknik PTS, maka pada penelitian ini dibandingkan dua skema antara sistem OFDM tanpa dan dengan teknik PTS menggunakan analisa pada bit error rate dan nilai CCDF. Dari hasil pengukuran menunjukkan bahwa implementasi kinerja teknik PTS mampu meningkatkan kinerja sistem OFDM saat terkena distorsi nonlinear, terlihat pada pengukuran dengan modulasi 16-QAM untuk gain 56 didapatkan peningkatan BER sebesar 95.98%. Sedangkan pada grafik CCDF terjadi penurunan nilai PAPR sebesar 34.17% untuk M=4.

  12. KEEFEKTIFAN PEMBELAJARAN BERBANTUAN INTERNET DI SMK SE-KOTA YOGYAKARTA KOMPETENSI KEAHLIAN TEKNIK KOMPUTER DAN JARINGAN

    Directory of Open Access Journals (Sweden)

    Ganggang Canggi Arnanto

    2014-11-01

    Full Text Available Penelitian ini bertujuan untuk mengungkapkan keefektifan pembelajaran berbantuan internet di sekolah menengah kejuruan (SMK Se-Kota  Yogyakarta. Sekolah-sekolah tersebut dipilih yang memiliki kompetensi keahlian Teknik Komputer dan Jaringan (TKJ dan sudah melaksanakan pembelajaran berbantuan internet sebagai persiapan untuk menyambut Asian Community 2015 pada kerjasama Promoting Information and Comunication Technology (ICT, sehingga perlu diketahui sejauh mana keefektifannya. Penelitian ini merupakan penelitian expost facto. Variabel penelitiannya adalah penguasaan strategi pembelajaran guru, sikap siswa, kualifikasi guru, dan kelengkapan sarana dan prasarana laboratorium komputer. Populasi penelitian ini adalah siswa kelas 2 dan seluruh guru yang mengajar kelas 2 kompetensi keahlian teknik komputer dan jaringan. Instrumen yang digunakan dalam penelitian ini berupa angket untuk guru dan siswa, dan lembar observasi untuk kelengkapan sarana dan prasarana laboratorium komputer. Hasil analisis deskriptif mengungkapkan bahwa penguasaan strategi pembelajaran guru berada pada kategori baik (rerata 150,52 dengan tingkat kecendrungan sebesar 53,29% belum memenuhi standar yang telah ditetapkan pada kategori pembelajaran yang efektif, dan sikap siswa berada pada kategori baik (rerata 62,95 dengan tingkat kecendrungan sebesar 54,31%. Secara keseluruhan pembelajaran berbantuan internet di SMK Se-Kota Yogyakarta sudah efektif, meskipun penguasaan strategi pembelajaran guru perlu ditingkatkan dengan mengikutsertakan mereka pada pelatihan-pelatihan yang berhubungan dengan pembelajaran berbantuan internet.Kata kunci: keefektifan pembelajaran, sekolah menengah kejuruan, teknik komputer dan jaringan

  13. PENGEMBANGAN INSTRUMEN PENILAIAN KETERAMPILAN TEKNIK FOREHAND DAN BACKHAND DRIVE TENIS MEJA PADA ATLET USIA DINI

    Directory of Open Access Journals (Sweden)

    Verandita Rihtiana

    2014-09-01

    Full Text Available Penelitian ini bertujuan untuk mengembangkan instrumen penilaian keterampilan teknik forehand dan backhand drive tenis meja pada atlet usia dini. Penelitian ini menggunakan metode pene-litian dan pengembangan, dengan langkah-langkah pengembangan sebagai berikut: (1 pengumpulan informasi di lapangan, (2 melakukan analisis terhadap informasi yang dikumpulkan, (3 mengembangkan produk awal (draf model, (4 validasi ahli dan revisi, (5 uji coba skala kecil dan revisi, (6 uji coba skala besar dan revisi, (7 pembuatan produk final. Subjek penelitian atlet tenis meja usia dini. Analisis data untuk uji validitas dilakukan dengan CVR (content validity ratio dan reliabilitas dengan  menggunakan Alpha Crobanch. Penelitian ini menghasilkan buku panduan instrumen penilain keterampilan teknik forehand dan backhand drive tenis meja untuk atlet pemula  yang didalamnya berisi  petunjuk penggunaan, lembar tugas siswa, pedoman penilaian, rubrik penilaian, serta tabel penyekoran, yang memiliki validitas yang tinggi (1 dan reliabilitas yang tinggi¸forehand drive sikap awal: r = 0,975, pelaksanaan: r = 0,961, gerak lanjutan: r = 0, 955. Backhand drive sikap awal: r = 0,961, pelaksanaan r = 0,974, gerak lanjutan: r = 0, 989. Kata Kunci: instrumen penilaian teknik forehand dan backhand drive, tenis meja

  14. IDENTIFIKASI TINGKAT KUALITAS PELAYANAN JASA PENDIDIKAN DENGANMENGGUNAKAN SERVQUALDI FAKULTAS TEKNIK UNIVERSITAS X

    Directory of Open Access Journals (Sweden)

    Chalis Fajri Hasibuan

    2017-04-01

    Full Text Available Persaingan di dalam dunia pendidikan dewasa ini semakin ketat, khususnya perguruan tinggi, bukan hanya perguruan tinggi dalam negeri saja yang menjadi pesaing tetapi juga perguruan tinggi luar negeri.Minat masyarakat Indonesia semakin tinggi terhadap perguruan tinggi luar negeri yang menawarkan kualitas jasa pendidikan yang lebih baik. Adapun tujuan dalam penelitian ini yaitu Mengukur tingkat kepuasan mahasiswa/i Fakultas Teknik Universitas X terhadap pelayanan jasa yang diberikan oleh Fakultas Teknik Universitas X. Jenis penelitian yang digunakan adalah penelitian deskriptif dengan teknik survey.Metode yang digunakan adalah metode Servqual.Metode servqual digunakan untuk menentukan atribut serta mengukur kesenjangan (gap antara harapan dengan persepsi konsumen terhadap suatu pelayanan. Hasil penelitian diperoleh gap Dengan nilai terbesar yakni -0.9186 menunjukkan bahwa fasilitas yang diberikan belum sesuai dengan biaya uang kuliah yang dibayarkan oleh mahasiswa sedangkan Tingkat pendidikan Dosen yang mengajar di UMA sudah berpendidikan minimal S2 dengan gap yang bernilai positif sebesar 0.0679 yang mengindekasikan bahwa tingkat harapan yang ada pada mahasiswa lebih rendah dari kinerja yang diberikan oleh Universitas X.

  15. MENINGKATAKAN KEPERCAYAAN DIRI SISWA KORBAN BULLYING MELALUI KONSELING INDIVIDU TEKNIK HOMEWORK ASSIGMENT

    Directory of Open Access Journals (Sweden)

    Gus Riries Nahdliyatul Awaliyah

    2014-06-01

    Full Text Available Tujuan penelitian ini untuk memperoleh informasi atau temuan empiris tentang meningkatkan kepercayaan diri siswa korban bullying melalui konseling individu rational emotif behavior teknik therapy homework assignment pada siswa kelas VIII A SMP Diponegoro 7 Gumelar. Populasinya adalah siswa SMP Diponegoro 7 Gumelar Kabupaten Banyumasdan sampel yang berjumlah 6 siswa menggunakan purposeive sampling. Teknik pengumpulan data menggunakan wawancara dan observasi. Teknik analisis data yang digunakan yakni analisis deskriptif persentase dan triangulasi sumber. Hasil penelitian ini menunjukan bahwa terdapat perbedaan kepercayaan diri sebelum dan sesudah treatment. Simpulan dari penelitian ini yakni konseling individu rational emotif behavior therapy teknik home work assignment dapat meningkatkan kepercayaan diri siswa korban bullying.Oleh karena itu, diharapkan guru pembimbing melakukan penanganan lebih dini jika menemukan siswa yang menjadi korban bullying agar aktifitas serta interaksi sosial mereka di sekolah tidak terganggu. Salah satu cara yang dapat digunakan adalah konseling individu pendekatan rational emotif behavior therapy dengan menggunakan teknik home work assignment. The purposeof this study is to get information or empirical finding about the increasing confidence of bullied students as the effect of individual counseling rational emotive behavior therapy technique with home-work assignment inclass VIII A Diponegoro 7 Gumelar Junior High School. Population are students in Diponegoro 7 Gumelar junior high school.  Purposive sampling technique was used in this study, samples were 6 students of the class VIII A.Data collection techniquesusinginterviews and observations. Data analysis used descriptive percentage, and triangulation of sources. The result of this study showed there were differences in self-confidence before and after treatment.From this research it can be conluded thatthe individual counseling rational emotive behavior therapy

  16. Meningkatakan Kepercayaan Diri Siswa Korban Bullying Melalui Konseling Individu Teknik Homework Assigment

    Directory of Open Access Journals (Sweden)

    Gus Riries Nahdliyatul Awaliyah

    2014-06-01

    Full Text Available Tujuan penelitian ini untuk memperoleh informasi atau temuan empiris tentang meningkatkan kepercayaan diri siswa korban bullying melalui konseling individu rational emotif behavior teknik therapy homework assignment pada siswa kelas VIII A SMP Diponegoro 7 Gumelar. Populasinya adalah siswa SMP Diponegoro 7 Gumelar Kabupaten Banyumasdan sampel yang berjumlah 6 siswa menggunakan purposeive sampling. Teknik pengumpulan data menggunakan wawancara dan observasi. Teknik analisis data yang digunakan yakni analisis deskriptif persentase dan triangulasi sumber. Hasil penelitian ini menunjukan bahwa terdapat perbedaan kepercayaan diri sebelum dan sesudah treatment. Simpulan dari penelitian ini yakni konseling individu rational emotif behavior therapy teknik home work assignment dapat meningkatkan kepercayaan diri siswa korban bullying.Oleh karena itu, diharapkan guru pembimbing melakukan penanganan lebih dini jika menemukan siswa yang menjadi korban bullying agar aktifitas serta interaksi sosial mereka di sekolah tidak terganggu. Salah satu cara yang dapat digunakan adalah konseling individu pendekatan rational emotif behavior therapy dengan menggunakan teknik home work assignment. The purposeof this study is to get information or empirical finding about the increasing confidence of bullied students as the effect of individual counseling rational emotive behavior therapy technique with home-work assignment inclass VIII A Diponegoro 7 Gumelar Junior High School. Population are students in Diponegoro 7 Gumelar junior high school.  Purposive sampling technique was used in this study, samples were 6 students of the class VIII A.Data collection techniquesusinginterviews and observations. Data analysis used descriptive percentage, and triangulation of sources. The result of this study showed there were differences in self-confidence before and after treatment.From this research it can be conluded thatthe individual counseling rational emotive behavior therapy

  17. Corrosion product layers on magnesium alloys AZ31 and AZ61: Surface chemistry and protective ability

    International Nuclear Information System (INIS)

    Feliu, S.; Llorente, I.

    2015-01-01

    Highlights: • Surface chemistry of the corrosion product layers on magnesium alloys. • Influence of the type of alloy on the carbonate surface enrichment. • Relation between surface composition and protection properties. - Abstract: This paper studies the chemical composition of the corrosion product layers formed on magnesium alloys AZ31 and AZ61 following immersion in 0.6 M NaCl, with a view to better understanding their protective action. Relative differences in the chemical nature of the layers were quantified by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDX) and low-angle X-ray diffraction (XRD). Corrosion behavior was investigated by Electrochemical Impedance Spectroscopy (EIS) and hydrogen evolution measurement. An inhibitive effect from the corrosion product layers was observed from EIS, principally in the case of AZ31, as confirmed by hydrogen evolution tests. A link was found between carbonate enrichment observed by XPS in the surface of the corrosion product layer, concomitant with the increase in the protective properties observed by EIS

  18. Corrosion product layers on magnesium alloys AZ31 and AZ61: Surface chemistry and protective ability

    Energy Technology Data Exchange (ETDEWEB)

    Feliu, S., E-mail: sfeliu@cenim.csic.es; Llorente, I.

    2015-08-30

    Highlights: • Surface chemistry of the corrosion product layers on magnesium alloys. • Influence of the type of alloy on the carbonate surface enrichment. • Relation between surface composition and protection properties. - Abstract: This paper studies the chemical composition of the corrosion product layers formed on magnesium alloys AZ31 and AZ61 following immersion in 0.6 M NaCl, with a view to better understanding their protective action. Relative differences in the chemical nature of the layers were quantified by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDX) and low-angle X-ray diffraction (XRD). Corrosion behavior was investigated by Electrochemical Impedance Spectroscopy (EIS) and hydrogen evolution measurement. An inhibitive effect from the corrosion product layers was observed from EIS, principally in the case of AZ31, as confirmed by hydrogen evolution tests. A link was found between carbonate enrichment observed by XPS in the surface of the corrosion product layer, concomitant with the increase in the protective properties observed by EIS.

  19. Facebook Marketing - Fra A-Z

    DEFF Research Database (Denmark)

    Mortensen, Thomas Bøtker

    2009-01-01

    Facebook Marketing – Leverage Social Media to Grow Your Business af Steven Holzner er Facebook Marketing fra A-Z, som kan anbefales til virksomheder, som overvejer at bevæge sig ud i cyber space og afprøve mulighederne for at markedsføre sig dér. Bogen beskriver på hvilke væsentlige punkter...... marketing på Facebook adskiller sig fra traditionel marketing, og gennemgår trin for trin de fundamentale ting, som man skal vide for, at virksomheden kan agere med den tilsigtede effekt i et socialt netværk som Facebook. Og eftersom 34 % af den danske befolkning i dag er hoppet med på Facebook vognen og...... har oprettet en profil på Facebook, er potentialet åbenlyst....

  20. A comparative corrosion behavior of Mg, AZ31 and AZ91 alloys in 3.5% NaCl solution

    Directory of Open Access Journals (Sweden)

    I.B. Singh

    2015-06-01

    Full Text Available The corrosion behavior of Mg, AZ31 and AZ91 has been evaluated in 3.5% NaCl solution using weight loss, electrochemical polarization and impedance measurements. Corrosion rate derived from the weight losses demonstrated the occurrence of steeply fast corrosion reaction on AZ91 alloy after three hours of immersion, indicating the start of galvanic corrosion. An increase of corrosion rate with immersion time was also observed for AZ31 but with lesser extent than AZ91 alloy. Whereas Mg metals showed a decrease of corrosion rate with immersion time, suggesting the formation of a protective layer on their surfaces. In contrast, the corrosion current density (Icorr derived from the Tafel plots, exhibited their corrosion resistances in order of Mg > AZ91 > AZ31. Electrochemical charge transfer resistance (Rct and double layer capacitance measured by electrochemical impedance spectroscopy (EIS, are well in accordance with the measured Icorr. EIS measurements with time and microstructural examination of the corroded and uncorroded samples are helpful in elucidation of results measured by electrochemical polarization.

  1. APLIKASI KRS ONLINE BERBASIS WEB DAN MOBILE PADA PROGRAM STUDI DIII TEKNIK KOMPUTER POLITEKNIK HARAPAN BERSAMA TEGAL

    Directory of Open Access Journals (Sweden)

    Dwi Wahyu Susanti

    2016-03-01

    Full Text Available Pengisian Kartu Rencana Studi (KRS merupakan bagian yang berperan penting dalam sistemakademik Program Studi DIII Teknik Komputer PoliTeknik Harapan Bersama Tegal. Sistem pengisianKRS yang berjalan selama ini di masih menggunakan sistem manual sehingga dengan semakinbanyaknya jumlah mahasiswa membuat sistem ini tidak efisien baik dari segi waktu maupun biaya.Pembuatan aplikasi KRS online berbasis web dan mobile bertujuan untuk menggantikan sistem KRSmanual yang berjalan saat ini agar nantinya kegiatan perkuliahan mahasiswa dapat berjalan lancar.Dalam pembuatan sistem ini menggunakan metode observasi, wawancara serta studi literatur, denganmenggunakan sample data di antaranya data mahasiswa, data mata kuliah semester 1 sampai dengansemester 6 serta data dosen pembimbing akademik Prodi DIII Teknik Komputer Tahun akademik2013/ 2014. Perangkat keras yang digunakan yaitu 1 unit laptop Compaq Presario CQ43 denganspesifikasi processor AMD E-300, RAM 2,0 GB serta OS Windows 7 Ultimate. Sedangkan perangkatlunak yang digunakan yaitu bahasa pemrograman PHP untuk aplikasi berbasis web dan XHTML untukaplikasi berbasis mobile, MYSQL, XAMPP dan web editor Macromedia Dreamweaver 6. Hasilpenelitian ini menunjukkan bahwa dengan diterapkannya sistem baru yaitu dengan dibuatnya aplikasipengisian KRS online berbasis web dan mobile di Program Studi DIII Teknik Komputer PoliTeknikHarapan Bersama maka proses pengisian KRS akan lebih praktis dan efisien baik dari segi waktumaupun biaya.Kata Kunci : KRS Online, Web, Mobile.

  2. PERANCANGAN DAN IMPLEMENTASI SISTEM PENGUKURAN KINERJA DENGAN METODE INTEGRATED PERFORMANCE MEASUREMENT SYSTEMS (Studi Kasus: Jurusan Teknik Mesin Universitas Mataram

    Directory of Open Access Journals (Sweden)

    Bambang Syairuddin

    2007-01-01

    Full Text Available To assure the quality of education in the Department of Mechanical Engineering, we need to design an integrated performance measurement system. For that purpose, we used the IPMS (Integrated Performance Measurement Systems method. Using the IPMS method, Key Performance Indicators (KPIs of the Department of Mechanical Engineering were determined by pursuant to stakeholder requirement through four steps. Those are identifying the stakeholder requirement, external monitor, stipulating objectives, and identification of KPIs. Performance measurement system with the IPMS method in the Department of Mechanical Engineering of Mataram University can be identified into 38 KPIs grouped in 9 criterias of performance of the Department of Mechanical Engineering, that are curriculum, student, financial, human resources, administration academic, teaching and learning, alumnus, evaluation and operation, and external party. Abstract in Bahasa Indonesia : Untuk menjamin kualitas pendidikan di Jurusan Teknik Mesin, diperlukan sebuah rancangan sistem pengukuran kinerja (SPK yang terintegrasi dengan metode IPMS (Integrated Performance Measurement Systems. Dengan metode IPMS, Key Performance Indicators (KPI Jurusan Teknik Mesin ditentukan berdasarkan stakeholder requirement melalui empat tahapan yaitu; identifikasi stakeholder requirement, external monitor, penetapan objectives, dan identifikasi KPIs. Hasil perancangan SPK di Jurusan Teknik Mesin Universitas Mataram, dapat mengidentifikasi 38 KPIs yang dikelompokkan dalam 9 kriteria kinerja Jurusan Teknik Mesin, yaitu; kurikulum, mahasiswa, finansial, SDM, administrasi akademik, proses pembelajaran, alumni, evaluasi dan pengendalian, dan external party. Kata Kunci : Sistem Pengukuran Kinerja, IPMS, Teknik Mesin Unram.

  3. Recommendation Report: EJournals/EBooks A-Z Management System

    KAUST Repository

    Ramli, Rindra M.

    2014-01-01

    This is a recommendation report for KAUST Library on the Ejournals / EBooks AZ Management systems project. It briefly described the issues faced by the ERM Team, project plan overview and the project findings as well as the recommendation(s).

  4. MANFAAT TEKNIK RELAKSASI MASSAGE MUSCULLUS TRAPEZIUS DENGAN AROMATERAPI MAWAR TERHADAP PERUBAHAN TEKANAN DARAH PADA IBU HAMIL

    Directory of Open Access Journals (Sweden)

    Ernawati Ernawati

    2017-02-01

    Full Text Available Hipertensi dalam kehamilan merupakan 5-5% penyulit kehamilan dan merupakan salah satu dari tiga penyebab tertinggi mortalitas dan morbiditas ibu bersalin di Indonesia. Terdapat 2 cara mengatasi hipertensi yang dapat dilakukan yaitu secara farmakologis dan non farmakologis. Beberapa jenis penanganan non farmakologi yang dapat dilakukan adalah akupresur (akupuntur tanpa jarum, terapi herbal, terapi jus, pijat (massage, yoga, aromaterapi, pernafasan dan relaksasi, meditasi, hypnosis dan perawatan dirumah. Tujuan penelitian ini adalah untuk mengetahui manfaat teknik relaksasi massage muscullus trapezius dengan aromaterapi mawar terhadap perubahan tekanan darah pada ibu hamil. Penelitian ini menggunakan rancangan kuantitatif dengan pendekatan cross sectional. Subyek dalam penelitian ini berjumlah 38 ibu hamil. Penelitian yang dilakukan di RSUD Hj. Anna Lasmanah Banjarnegara periode 4 Januari sampai 19 Februari 2016. Teknik pengambilan sampel dalam penelitian ini adalah Purposive Sampling. Data diperoleh melalui observasi langsung. Analisis data dilakukan dengan rumus t-test of related menggunakan pengolahan komputerisasi statiscal product and serve solution (SPSS 17. Hasil analisis data didapatkan nilai thitung sebesar 9,932 untuk tekanan darah sistol dan thitung 6,173 untuk tekanan darah diastole. Jika df=38-1=37 dan ?=0,05 maka didapatkan ttabel 2,042. thitung ? ttabel maka Ho diterima, Ha ditolak dan jika t hitung ? t tabel maka Ho ditolak, Ha diterima. Dalam uji hipotesis didapatkan t hitung ? t table (9,932>2,042 dan (6,173>2,042, maka dapat disimpulkan bahwa Ho ditolak dan Ha diterima. Maka terdapat manfaat teknik relaksasi massage muscullus trapezius dengan aromaterapi mawar terhadap perubahan tekanan darah pada ibu hamil.

  5. Meningkatkan Interaksi Sosial Siswa Melalui Layanan Bimbingan Kelompok Teknik Permainan Social Playing

    Directory of Open Access Journals (Sweden)

    Nurul Rizkiana

    2014-12-01

    Full Text Available Tujuan dari penelitian ini adalah untuk memperoleh data empiris tentang peningkatan interaksi sosial pada siswa kelas VII G melalui layanan bimbingan kelompok teknik permainan social playing. Jenis penelitian yang digunakan adalah penelitian eksperimen Populasi dalam penelitian ini adalah siswa kelas VII G SMP Negeri 3. Teknik pengambilan sampel dalam penelitian ini adalah purposive sampling. Sampel dalam penelitian ini adalah 10 siswa dengan kemampuan interaksi sosial tinggi, sedang, rendah, dan sangat rendah. Metode pengumpulan data dalam penelitian ini menggunakan skala interaksi sosial. Metode analisis data yaitu deskriptif persentase dan uji hipotesis dengan uji Wilcoxon. Hasil penelitian ini yaitu setelah memperoleh layanan bimbingan kelompok dengan teknik permainan social playing, kriteria interaksi sosial siswa menjadi tinggi (80.04%. Dari uji Wilcoxon diperoleh Zhitung sebesar 2.80 dan nilai Ztabel pada taraf kesalahan 0.025 dan  n=10 yaitu 1.96. Sehingga dapat disimpulkan bahwa interaksi sosial pada siswa kelas VII G SMP Negeri 3 Ungaran dapat ditingkatkan melalui layanan bimbingan kelompok dengan teknik permainan social playing. The purpose from this research is to get empirical data about the increase of social interaction in seven G student. Through guidance service group social playing games. This type of research is experimental research, the population in this research is experimental research, the population in this research is seven G students in junior high school 3 Ungaran. Sampling technique in this research was purposive sampling. The samples have been taken on this research is 10 students with the ability of social interaction is high, medium, low, and very low. Method of collecting data in this research is using social interaction scale. Analysis methods data is descriptive percentage and hypothesis testing with wilcoxon test. The result in this research is after receiving guidance service group with social playing

  6. TEKNIK ISOLASI - IDENTIFIKASI Yersinia pestis SEBAGAI PENYEBAB PENYAKIT PES (HASIL PELATIHAN DI BALAI BESAR VETERINER BOGOR

    Directory of Open Access Journals (Sweden)

    Dewi Marbawati

    2012-11-01

    Full Text Available Teknik isolasi dan identifikasi Y. pestis mempunyai prinsip- prinsip umum pertumbuhan yaitu terdiri dari tiga tahap yaitu: tahap pengkayaan, seleksi pada media agar dan uji biokimia. Tahap pengkayaan dilakukan dengan cara menimbang sebanyak 10-25 gram spesimen kemudian dimasukkan dalam blender atau plastik steril dan ditambah 90-225 ml media pengkayaan (dapat menggunakan Buffered Peptone Water (BPW, Brain Heart Infusion (BHI atau menggunakan Nutrient Broth. Setelah itu dibuat suspensi spesimen 10%, kemudian dilakukan homogenisasi selama ± 2 menit dan diinkubasikan pada suhu 37 derajat Celcius selama 24 jam.

  7. Pemanfaatan Limbah Ranting Kayu Manis (Cinnamomun Burmanii untuk Penciptaan Seni Kerajinan dengan Teknik Laminasi

    Directory of Open Access Journals (Sweden)

    Edi Eskak

    2016-04-01

    Full Text Available ABSTRAKLimbah ranting kayu manis (Cinnamomum burmanii merupakan sisa kayu yang tidak ikut dikupas untuk diambil kulitnya sebagai bahan rempah-rempah. Limbah ranting ini jumlahnya cukup banyak pada saat panen kulit kayu manis. Pada saat ini limbah tersebut hanya dibuang ataupun dibakar. Penciptaan seni ini bertujuan untuk memanfaatan limbah ranting kayu manis tersebut menjadi aneka produk seni kerajinan. Metode yang digunakan yaitu eksplorasi, perancangan, dan perwujudan karya. Hasilnya berupa prototip produk kerajinan dengan teknik laminasi yaitu berupa: tatakan saji (tatakan gelas, mangkuk, dan piring, pigura foto, dan aneka wadah. Metode dan prototip produknya dapat dijadikan model untuk pemberdayaan industri kreatif masyarakat daerah penghasil kayu manis. Dari penciptaan seni ini dapat disimpulkan bahwa limbah ranting kayu manis bisa ditingkatkan kemanfaatan dan nilai ekonomisnya menjadi lebih tinggi dengan mengreasikannya menjadi aneka produk seni kerajinan dengan aplikasi teknik laminasi. Teknik laminasi dipilih untuk mengolah limbah ranting yang berukuran kecil agar dapat menjadi aneka produk dengan ukuran variatif yang lebih besar. Keunggulan kerajinan limbah ranting kayu manis ini adalah memiliki aroma harum alami kayu manis yang khas. Kata kunci: limbah ranting, kayu manis, seni kerajinan, teknik laminasiABSTRACTWaste of cinnamon twig (Cinnamomum burmanii is the rest of the wood unpeeled for its pelt as a spice. These twigswaste are quite a lot at the time of harvesting cinnamon bark. At this time the waste is simply dumped or burned as trash. The creation of art aims to utilize waste into cinnamon twig art craft products. The method used is the exploration, design, and realization of the work. The result is a prototype craft products with lamination techniques those are: food placemat (coasters, bowls, and plates, picture frames, and various containers. Method and prototype products can be used as a model for community empowerment

  8. Meningkatkan Motivasi Belajar Siswa Melalui Layanan Penguasaan Konten dengan Teknik Bermain Peran

    Directory of Open Access Journals (Sweden)

    Lilik Maryanto

    2014-09-01

    Full Text Available Penelitian ini bertujuan untuk membuktikan apakah layanan penguasaan konten dengan teknik bermain peran dapat meningkatkan motivasi belajar siswa. Jenis penelitian ini adalah penelitian eksperimen dengan desain one group pre-test and post test. Populasi penelitian ini adalah semua siswa kelas 5 MI AL Islam Mangunsari 02 Semarang yang berjumlah 21 siswa. Teknik sampling jenuh digunakan karena jumlah populasi relatif kecil (kurang dari 30 orang dimana seluruh populasi digunakan menjadi sampel. Metode pengumpulan data menggunakan skala psikologi dengan instrument skala motivasi belajar sebanyak 68 item pernyataan. Metode analisis data menggunakan deskriptif presentase dan uji t-Test. Perlakuan berupa layanan penguasaan konten dengan teknik bermain peran dilakukan sebanyak 8 kali pertemuan tatap muka. Berdasarkan hasil penelitian menunjukkan peningkatan motivasi belajar siswa antara sebelum perlakuan (62% dan sesudah perlakuan (77%, mengalami peningkatan sebesar 15%. Berdasarkan analisis t-Test dengan menggunakan taraf signifikan 5%, hasil analisis uji beda diperoleh thitung = 10.16 dan ttabel = 2,045, jadi nilai thitung > ttabel, sehingga dinyatakan bahwa Ha diterima dan dapat disimpulkan bahwa terdapat peningkatan motivasi belajar siswa. Hasil penelitian ini menunjukkan bahwa layanan penguasaan konten dengan teknik bermain peran (role playing dapat digunakan sebagai upaya untuk meningkatkan motivasi belajar siswa kelas 5 MI AL Islam Mangunsari 02 Semarang.   This research aimed to prove whether the content mastery service with techniques playing role (role playing can increase students' motivation. This type of research is experiments research by design one group pre-test and post test. This research population is all students 5th grade MI AL Islam Mangunsari 02 Semarang, which amounts 21 students. Saturated sampling technique is used because the population is relatively small (less than 30 people where the entire populations is used to be

  9. MENARIK MINAT SISWA PADA LAYANAN BIMBINGAN DAN KONSELING ISLAMI DI SEKOLAH MENGGUNAKAN LAYANAN INFORMASI DENGAN TEKNIK MODELLING

    Directory of Open Access Journals (Sweden)

    Ismah -

    2016-08-01

    Full Text Available Rendahnya minat siswa pada layanan bimbingan dan konseling terlihat dari minimnya siswa yang datang keruang BK untuk memanfaatkan layanan bimbingan dan konseling di sekolah. Permasalahan yang dikaji dalam penulisan ini adalah, Bagaiman layanan informasi dengan teknik modelling dapat menarik terhadap minat siswa pada layanan bimbingan dan konseling di sekolah khususnya bimbingan dan konseling islami. Tujuan yang hendak dicapai dalam penulisan ini adalah untuk memberi masukan kepada guru BK di sekolah supaya siswa-siswinya tertarik atau berminat berkunjung di ruang BK, menggunakan cara ”layanan informasi dengan teknik modelling terhadap minat siswa pada layanan bimbingan dan konseling siswa di sekolah khususnya bimbingan dan konseling islami”. Pada kajian ini dapat dianalisis bahwa: layanan informasi dengan teknik modelling, diharapkan dapat berdampak positif terhadap minat siswa berkunjung ke ruang BK, sehingga guru BK dapat memberi layanan bimbingan konseling khusunya bimbingan dan konseling islami dengan kesadaran siswa tanpa pemaksaan.

  10. 241-AZ-101 pump removal trough analysis

    International Nuclear Information System (INIS)

    Coverdell, B.L.

    1995-01-01

    As part of the current Hanford mission of environmental cleanup, various long length equipment must be removed from highly radioactive waste tanks. The removal of equipment will utilize portions of the Equipment Removal System for Project W320 (ERS-W320), specifically the 50 ton hydraulic trailer system. Because the ERS-W320 system was designed to accommodate much heavier equipment it is adequate to support the dead weight of the trough, carriage and related equipment for 241AZ101 pump removal project. However, the ERS-W320 components when combined with the trough and its' related components must also be analyzed for overturning due to wind loads. Two troughs were designed, one for the 20 in. diameter carriage and one for the 36 in. diameter carriage. A proposed 52 in. trough was not designed and, therefore is not included in this document. In order to fit in the ERS-W320 strongback the troughs were design with the same widths. Structurally, the only difference between the two troughs is that more material was removed from the stiffener plates on the 36 in trough. The reduction in stiffener plate material reduces the allowable load. Therefore, only the 36 in. trough was analyzed

  11. ANALISA OPTIMALISASI TEKNIK ESTIMASI DAN KOMPENSASI GERAK PADA ENKODER VIDEO H.263

    Directory of Open Access Journals (Sweden)

    Oka Widyantara

    2009-05-01

    Full Text Available Mode baseline encoder video H.263 menerapkan teknik estimasi dan kompensasi gerak dengan satu vector gerak untuk setiap macroblock. Prosedur area pencarian menggunakan pencarian penuh dengan akurasi setengah pixel pada bidang [16,15.5] membuat prediksi di tepian frame tidak dapat diprediksi dengan baik. Peningkatan unjuk kerja pengkodean prediksi interframe encoder video H.263 dengan optimalisasi teknik estimasi dan kompensasi gerak diimplementasikan dengan penambahan area pencarian [31.5,31.5] (unrestricted motion vector, Annex D dan 4 motion vector (advanced prediction mode, Annex F. Hasil penelitian menunjukkan bahwa advanced mode mampu meningkatkan nilai SNR sebesar 0.03 dB untuk sequence video claire, 0.2 dB untuk sequence video foreman, 0.041 dB untuk sequence video Glasgow, dan juga mampu menurunkan bit rate pengkodean sebesar 2.3 % untuk video Claire, 15.63 % untuk video Foreman,  dan 9.8% untuk video Glasgow dibandingkan dengan implementasi 1 motion vector pada pengkodean baseline mode.

  12. PENGEMBANGAN SISTEM TES DIAGNOSTIK KESULITAN BELAJAR BERBASIS WEB MAHASISWA JURUSAN TEKNIK MESIN

    Directory of Open Access Journals (Sweden)

    Soffan Nurhaji

    2016-07-01

    Full Text Available Penelitian ini bertujuan untuk: (a Merancang sistem tes diagnostik kesulitan belajar mahasiswa jurusan pendidikan teknik mesin, dan, dan (b mengembangkan sistem tes diagnostik kesulitan belajar Mahasiswa. Penelitian ini menggunakan pendekatan Research and Development dengan perangkat lunak. Model pengembangan yang digunakan dalam penelitian ini adalah model modifikasi linear sequential yang disebut juga sebagai classic life cycle atau model waterfall yang memiliki 4 langkah. Analisis kebutuhan sistem dan perancangan sistem telah dilakukan pada tahun kedua. Implementasi dan validasi program dilakukan pada tahun keempat. Validasi sistem dilakukan dengan angket yang diberikan kepada 6 dosen yang mengampu di jurusan teknik pendidikan mesin untuk melihat aspek kinerja, rancangan, dan aksesbilitas sistem. Analisis data validasi dilakukan dengan statistik deskriptif. Langkah terakhir, evaluasi pemanfaatan sistem, akan dilaksanakan pada tahun kelima. Sistem tes diagnostik kesulitan belajar akan dikembangkan dengan arsitektur web client-server. Sistem ini memiliki tiga kelompok pengguna, yaitu admin, dosen, dan mahasiswa. Hasil analisis aspek kinerja, rancangan, dan adaptabilitas sistem secara keseluruhan akan dianalisis dari angket yang mempunyai rata-rata penilaian yang diperoleh dari skala 1–4, sehingga termasuk kategori sangat baik. Karena itu sistem yang telah dikembangkan dapat digunakan pada penelitian lebih lanjut pada tahun keenam, yaitu evaluasi pemanfaatan sistem. 

  13. STUDI EVALUASI SISTEM PENGKONDISIAN UDARA DI JURUSAN TEKNIK ELEKTRO KAMPUS BUKIT JIMBARAN DENGAN MENGGUNAKAN SOFTWARE

    Directory of Open Access Journals (Sweden)

    Muhammad Nur Hanifan

    2015-10-01

    Full Text Available ABSTRAK Pada gedung Jurusan Teknik Elektro Fakultas Teknik Universitas Udayana, banyak menggunakan energi listrik untuk berbagai sarana dalam memberi kenyamanan bagi mahasiswa maupun staff. Salah satu usaha dalam memberi kenyamanan tersebut adalah dengan memasang sistem pengkondisian udara. Karena banyaknya ruangan yang menggunakan sistem pengkondisian udara, maka diperlukan evaluasi pada kapasitas sistem pengkondisian udara tersebut sehingga dapat diketahui kondisi besar kapasitas AC terpasang. Pemakaian software dalam penghitungan akan sangat membantu kecepatan dalam penghitungan kapasitas sistem pengkondisian udara yang dibuat dengan menggunakan Microsoft Visual Studio. Selain itu evaluasi dilakukan pada penggunaan timer pada gedung DH karena timer pada gedung DH sudah tidak bekerja dengan baik dan waktu operasi AC belum efektif. Pada hasil perhitungan terdapat 18 ruangan dimana kapasitas AC terpasang kurang dari hasil perhitungan dan 3 ruangan kapasitas AC terpasang melebihi hasil perhitungan. Hal ini disebabkan penghitungan kapasitas AC terpasang belum menambahkan faktor penambahan kalor dari luar dan dari dalam ruangan. Evaluasi kinerja timer yang dilakukan pada gedung DH yaitu dengan mengevaluasi waktu operasi AC dimana kerja AC sebelumnya 8 jam waktu operasi selama 7 hari dikurangi menjadi 8 jam selama 5 hari karena pada hari sabtu dan minggu merupakan hari libur kuliah sehingga konsumsi energi listrik berkurang sebesar 580,34 kWh/minggu Kata kunci : Evaluasi, Air Conditioner (AC, Kapasitas AC.

  14. Perancangan Low Noise Amplifier dengan Teknik Non Simultaneous Conjugate Match untuk Aplikasi Radar S-Band

    Directory of Open Access Journals (Sweden)

    Yana Taryana

    2016-06-01

    Full Text Available Radar merupakan sistem pemancar dan penerima gelombang elektromagnetik untuk mendeteksi, mengukur jarak dan membuat peta benda benda seperti pesawat terbang, kapal laut, kendaran bermotor dan informasi cuaca. Salah satu kendala yang dihadapi pada sistem radar adalah sinyal pantulan yang memiliki daya yang rendah sehingga kualitas penerimaan menjadi kurang baik. Untuk mengatasi kendala tersebut dibutuhkan penguat daya pada sistem penerima yaitu Low Noise Amplifier (LNA. Oleh karena itu, tulisan ini memaparkan perancangan LNA dengan menggunakan teknik Non Simultaneous Conjugate Match (NSCM untuk aplikasi radar S-Band. Teknik ini memberikan kemudahan dalam menentukan nilai trade off (TO untuk nilai gain, noise figure (NF dan Voltage Standing Wave Ratio (VSWR yang diinginkan. Dalam proses perancangannya, perangkat lunak Agilent Design System (ADS 2011 digunakan untuk mendapatkan hubungan antara lingkaran gain, lingkaran NF, lingkaran VSWR, dan lingkaran mismatch factor (M. Dari hubungan tersebut diperoleh nilai impedansi masukan dan keluaran dari komponen aktif. Dalam tulisan ini, LNA dirancang dua tingkat untuk mendapatkan penguatan yang tinggi. Masing-masing tingkat menggunakan komponen aktif BJT BFP420 dengan penguatan dirancang sebesar 13,50 dB untuk tingkat pertama dan kedua, dan M sebesar 0,98. Sedangkan untuk saluran penyesuai impedansinya menggunakan substrat teflon fiberglass DiClad527. Hasil simulasi menunjukkan karakteristik LNA pada frekuensi 3 GHz yaitu gain sebesar 28,80 dB, NF sebesar 2,80 dB, VSWRin sebesar 1,05 dan VSWRout sebesar 1,1.

  15. Teknik Penyembunyian dan Enkripsi Pesan pada Citra Digital dengan Kombinasi Metode LSB dan RSA

    Directory of Open Access Journals (Sweden)

    Antonius Erick Handoyo

    2018-02-01

    Full Text Available This study proposed a combination of steganography and cryptography techniques using LSB and RSA methods. RSA is a popular cryptographic technique that can be applied to digital imagery. Digital image pixel values range from 0 to 255, making the keys used in RSA limited enough and less secure. So in this study, it is proposed to convert pixel image value to 16 bits so that the key used can be more varied. Experimental results proved that there was a steady increase in security and imperceptibility. This was shown by the results of PSNR 57.2258dB and MSE 0.1232dB. This method was also resistant to salt and pepper attacks. Penelitian ini mengusulkan kombinasi teknik steganografi dan kriptografi menggunakan metode LSB – RSA. RSA merupakan teknik kriptografi yang populer dapat diterapkan pada citra digital. Nilai piksel citra digital hanya berkisar 0 sampai 255. Hal ini membuat kunci yang digunakan dalam RSA cukup terbatas sehingga kurang aman. Dalam penelitian ini diusulkan untuk mengkonversi nilai piksel citra menjadi 16 bit sehingga kunci yang digunakan dapat lebih bervariasi. Hasil eksperimen membuktikan adanya peningkatan keamanan serta nilai imperceptibility yang tetap terjaga. Hal ini dibuktikan dengan hasil PSNR 57.2258dB, MSE 0.1232dB. Metode ini juga tahan terhadap serangan salt and pepper.

  16. PENGEMBANGAN MODEL PENDIDIKAN SOFT SKILL MELALUI PEMBELAJARAN PADA PROGRAM STUDI PENDIDIKAN TEKNIK MESIN FT UM

    Directory of Open Access Journals (Sweden)

    Dwi Agus Sudjimat

    2012-08-01

    Full Text Available The purpose of this research was to develop the soft skill education model at the Mechanical Engineering Education Study Program, State University of Malang included the curriculum and its implementation on the instructional activities. The research found that: (1 the soft skill curriculum needed by the Mechanical Engi­neering Education Study Program consists of fundamental skill, personal skill, and social skill; and (2 for implementing the soft skill curriculum entire the instructional activities strive for each lecture to take one or more soft skills statement for development, using the various strategies/methods of teaching refer to student-centered, giving tasks, and introducing the HES (Health and Environment Safety particularly in the practicum activities. Tujuan penelitian ini adalah untuk mengembangkan model pendidikan soft skill pada Program Studi Teknik Mesin Universitas Negeri Malang termasuk kuriku­lum dan implementasinya dalam kegiatan pembelajaran. Temuan penelitian ini adalah: (1 kurikulum soft skill yang diperlukan oleh Program Studi Teknik Mesin terdiri dari keterampilan dasar, keterampilan pribadi, dan keterampilan sosial, dan (2 menerap­kan kurikulum soft skill dalam pembelajaran pada masing-masing dasar, mengambil satu atau lebih soft skill untuk dikembangkan, menggunakan berbagai strategi/metode pengajaran berpusat pada mahasiswa, memberikan tugas, dan memperkenalkan K3 (Kesehatan dan Keselamatan Kerja, terutama dalam kegiatan praktikum.

  17. Caustic leaching of composite AZ-101/AZ-102 Hanford tank sludge

    International Nuclear Information System (INIS)

    Rapko, B.M.; Wagner, M.J.

    1997-07-01

    To reduce the quantity (and hence the cost) of glass canisters needed for disposing of high-level radioactive wastes from the Hanford tank farms, pretreatment processes are needed to remove as much nonradioactive material as possible. This report describes the results of a laboratory-scale caustic leaching test performed on a composite derived from a combination of 241-AZ-101 and 241-AZ-102 Hanford Tank sludges. The goals of this FY 1996 test were to evaluate the effectiveness of caustic leaching on removing key components from the sludge and to evaluate the effectiveness of varying the free-hydroxide concentrations by incrementally increasing the free hydroxide concentration of the leach steps up to 3 M free hydroxide. Particle-size analysis of the treated and untreated sludge indicated that the size and range of the sludge particles remained essentially unchanged by the caustic leaching treatment. Both before and after caustic leaching, a particle range of 0.2 microm to 50 microm was observed, with mean particle diameters of 8.5 to 9 microm based on the volume distribution and mean particle diameters of 0.3 to 0.4 microm based on the number distribution

  18. Perawatan Ortodontik Kaninus Kiri Maksil Impaksi di Daerah Palatal dengan Alat Cekat Teknik Begg

    Directory of Open Access Journals (Sweden)

    E. Emil

    2016-10-01

    Full Text Available Latar Belakang: ketidakharmonisan ukuran rahang dengan gigi merupakan salah satu bentuk etiologi maloklusi yang diturunkan dan akan mempengaruhi susunan dan posisi gigi di dalam rahang. Impaksi gigi seperti molar ketiga atau gigi kaninus sering kita temui akibat tidak adanya ruang untuk gigi tersebut erupsi dan menyusun diri di dalam lengkung yang baik. Gigi kaninus memiliki peran penting di dalam mulut, selain untuk mastikasi, gigi ini juga memiliki peran menentukan dalam estetika susunan gigi. Senyum yang menarik tidak akan didapatkan tanpa adanya gigi kaninus di dalam lengkung. Kasus impaksi kaninus dapat dirawat menggunakan teknik Begg dengan proses windowing yang dilakukan oleh ahli bedah mulut. Tujuan: membantu erupsi gigi kaninus dengan bantuan alat orto cekat teknik Begg. Kasus: laki-laki 19 tahun mengeluhkan gigi depan rahang atas protusif langit-langit tergigit oleh gigi depan rahang bawah. Diagnosis: maloklusi Angle kelas II dengan hubungan skeletal kelas I disertai kondisi berjejal di daerah anterior dan gigitan dalam. Perawatan: menggunakan alat cekat teknik Begg dan windowing dengan pencabutan dua premolar pertama rahang atas serta prosedur windo. Kesimpulan: hasil menunjukkan gigi kaninus kiri rahang atas dapat erupsi dengan baik dan bisa diposisikan ke dalam lengkung dalam 5 bulan.   Background: Discrepancy in size between jaw and teeth is one of the etiology factor of malocclusion that genetically inherited and will affect teeth allignment and position within the jaw. Third molar and canine impaction frequently found because there is not enough space for theme to erupt and align themselfes in a good alignment. Canine have an important role in mastication as it is in facial aesthetic. Canine impaction can be treated with Begg technique and windowing process performed by oral surgeon. Purpose: to help impacted canine to erupt using fixed Begg appliance technique and windowing process. Case: 19 years old man complained of crowded

  19. Perawatan Teknik Begg Pada Maloklusi Klas I Dengan Kaninus Impaksi dan Insisivus Lateral Agenesis

    Directory of Open Access Journals (Sweden)

    Kristina Wijaya Gunawan

    2013-06-01

    Full Text Available Impaksi kaninus maksila sering dijumpai pada sisi palatal daripada labial. Agenesis adalah anomali pertumbuhan akibat tidak ada satu atau lebih benih gigi. Laporan kasus ini bertujuan memaparkan kemajuan perawatan kasus Maloklusi klas I dengan kaninus impaksi dan insisivus lateral agenesis menggunakan alat cekat teknik Begg. Seorang pasien usia 20 tahun datang mengeluhkan gigi-gigi depan atas dan bawah yang berjejal sehingga mengganggu penampilan. Perawatan bertujuan untuk koreksi Maloklusi Angle klas I tipe dentoskeletal dengan deepbite, crossbite gigi 25 terhadap 35, pergeseran midline dental maksila dan mandibula ke kanan sebesar 2,5 mm dan 3,0 mm, 13 impaksi vertikal pada sisi labial, 42 agenesis, dan edentulous parsial regio 36. Koreksi dilakukan dengan pencabutan 14, 25, pemanfaatan ruang bekas pencabutan 36 dan exposure gigi kaninus yang impaksi. Tahap pertama teknik Begg adalah leveling, unraveling, dan bite opening, diikuti dengan koreksi midline dan penutupan sisa ruang bekas pencabutan. Kesimpulan: perawataan ortodontik menggunakan teknik Begg yang dilakukan simultan dengan exposure kaninus impaksi labial dengan closed eruption technique dapat memberikan hasil yang memuaskan. Treatment for Class I Malocclusion with Impacted Canine and Agenesis Lateral Incisor Using Begg Technique. Maxillary canine impaction occurs commonly on the palatal than labial side. Agenesis is a developmental anomaly condition because of the absence of one or more tooth buds. This case report aims to explain the treatment progress of class I malocclusion with impacted canine and agenesis lateral incisor using fixed appliance through Begg technique. A 20-year-old female patient complained about her upper and lower anterior dental crowding that disturbed her appearance. The treatment aims to correct the Angle class I malocclusion dentoskeletal types with deepbite, crossbite 25 to 35, maxillary and mandibulary dental midline shift to the right by 2.5 mm and 3.0 mm

  20. Perawatan Maloklusi Pseudo Kelas III dengan Alat Ortodontik Cekat Teknik Begg

    Directory of Open Access Journals (Sweden)

    Robertus Meidiyanto

    2016-10-01

    Full Text Available Latar Belakang: Maloklusi Pseudo kelas III ditandai dengan hubungan yang tidak harmonis antara relasi anteroposterior rahang dan posisi mandibula terhadap maksila. Ketidakharmonisan tersebut dapat disebabkan karena mandibula yang normal dengan maksila retrusif. Maloklusi pseudo kelas III mempunyai perhitungan yang menunjukkan bentuk antara klas I dan skeletal klas III. Perbedaanya hanya pada sudut gonial dimana pada skeletal klas III sudutnya lebih tumpul, sedangkan pada sampel pseudo klas III, sudut gonial lebih mirip dengan klas I. Perawatan ortodontik dengan alat cekat teknik Begg dapat juga untuk merawat maloklusi Angle kelas III, termasuk maloklusi skeletal yang menyertainya. Tujuan: memaparkan perubahan dental dan skeletal setelah perawatan dengan alat cekat teknik Begg. Kasus: perempuan 20 tahun mengeluhkan gigi-gigi rahang atas ada yang tumbuh di belakang dan rahang bawah nyakil sehingga menganggu penampilan dan mengurangi rasa percaya diri. Diagnosis: Maloklusi Angle Klas III subdivisi serta hubungan skeletal klas III dengan maksila retrusif dan mandibula protusif disertai Crossbite: 12, 11, 21, 22 terhadap 34, 32,31, 41, 42, 43. Perawatan: menggunakan alat cekat teknik Begg tanpa pencabutan. Kesimpulan: Hasil menunjukkan crowded terkoreksi, overjet dan overbite terkoreksi, relasi molar menjadi klas I.   Background: Pseudo class III malocclusion characterized by disharmony between anteroposterior relationship of jaw and mandibulae position toward maxilla. This disharmony cause by normally shaped mandibles and underveloped maxillae. Pseudo clas III malocclusion is an intermediate form between class I and skeletal clas III malocclusion. The only exception was the gonial angle, which was generally more obtuse in the skeletal class III sample. Measurement of gonial angle in the pseudo class III sample was found to be rather similar to class I sample. Fixed Begg orthodontic appliance can be used to treat Angle’s class III malocclusion

  1. AZ91C magnesium alloy modified by Cd

    DEFF Research Database (Denmark)

    Shabadi, R.; Ambat, Rajan; Dwarakadasa, E.S.

    2014-01-01

    In the present work, the effect of Cd on the microstructure, mechanical properties and general corrosion behaviour of AZ91C alloys was investigated. Addition of Cd was found not to be efficient in modifying/refining the microstructure or β-phase. A morphology change in β-phase from fine continuous...... precipitates to discontinuous β-phase upon the addition of Cd was observed. A marginal increment in mechanical properties was observed. General corrosion behaviour was followed with weight loss measurements, potentiostatic polarisation studies and surface studies in 3.5% sodium chloride solution and 3.......5% sodium chloride with 2% potassium dichromate solution. Cd addition deteriorated the corrosion behaviour of AZ91C. This behaviour was attributed to the formation of chunks of β-phase upon the addition of Cd. AZ91C with refined β-phase distribution, performed rather better in the NaCl solutions....

  2. AZ-101 Mixer Pump Test Qualification Test Procedures (QTP)

    International Nuclear Information System (INIS)

    THOMAS, W.K.

    2000-01-01

    Describes the Qualification test procedure for the AZ-101 Mixer Pump Data Acquisition System (DAS). The purpose of this Qualification Test Procedure (QTP) is to confirm that the AZ-101 Mixer Pump System has been properly programmed and hardware configured correctly. This QTP will test the software setpoints for the alarms and also check the wiring configuration from the SIMcart to the HMI. An Acceptance Test Procedure (ATP), similar to this QTP will be performed to test field devices and connections from the field

  3. PENGEMBANGAN APLIKASI LAYANAN INFORMASI KAMPUS PADA JURUSAN TEKNIK ELEKTRO UNIVERSITAS UDAYANA BERBASIS MOBILE DAN WEB SERVICE

    Directory of Open Access Journals (Sweden)

    Komang Isabella Anasthasia

    2014-12-01

    Full Text Available Selama ini, Jurusan Teknik Elektro Universitas Udayana telah memanfaatkan tiga media sebagai pertukaraninformasi, yaitu: halaman website, papan pengumuman, dan TV Jurusan. Namun, penyebaran informasi kemahasiswa terkadang datang dari mulut ke mulut sehingga informasi yang disampaikan menjadi kurang berkualitas.Penelitian ini akan merancang aplikasi layanan informasi kampus berbasis mobile dengan menggunakan fitur SMSdan aplikasi Android. Informasi yang diterima akan saling terintegrasi dan ditampilkan pada TV jurusan. Hasil akhirdari penelitian membuktikan bahwa web service JSON merupakan solusi dalam pengintegrasian informasi.Perangkat mobile yang dilengkapi dengan notifikasi membuat informasi tersebut dapat dikirim dan diterima kapanpun dan di mana pun. Informasi yang diterima juga lebih berkualitas apabila dilihat dari sisi ketersediaan,keakuratan sumber, dan ketepatan waktu.

  4. RANCANG BANGUN SISTEM TEMU KEMBALI INFORMASI ABSTRAK TUGAS AKHIR MAHASISWA PRODI TEKNIK INFORMATIKA UNSOED

    Directory of Open Access Journals (Sweden)

    Lasmedi Afuan

    2014-02-01

    Full Text Available Informasi merupakan hal yang sangat mudah didapatkan dan diakses. Tetapi terkadang informasi yang diperoleh tidak sesuai dengan apa yang diinginkan pengguna. Diperlukan sistem yang dapat membantu mencari informasi yang dibutuhkan secara efektif dan efisien. Sistem informasi ini sering kali disebut dengan istilah sistem temu kembali informasi (STKI. Pada penelitian ini membahas penerapan STKIuntuk melakukan pencarian abstrak Tugas Akhir yang relevan sesuai dengan query yang dimasukan oleh pengguna. STKI Abstrak tugas akhir yang dikembangkan menggunakan metode Vector Space Model (VSM dan metode pembobotan tf-idf, implementasi VSM dan metode tf-idf menggunakan bahasa pemrograman server side PHP dan Mysql sebagai DBMS untuk menyimpan informasi abstrak tugas akhir mahasiswa Prodi Teknik Informatika Unsoed

  5. Technical Analysis Feasibility Study on Smart Microgrid System in Sekolah Tinggi Teknik PLN

    Science.gov (United States)

    Suyanto, Heri

    2018-02-01

    Nowadays application of new and renewable energy as main resource of power plant has greatly increased. High penetration of renewable energy into the grid will influence the quality and reliability of the electricity system, due to the intermittent characteristic of new and renewable energy resources. Smart grid or microgrid technology has the ability to deal with this intermittent characteristic especially if these renewable energy resources integrated to grid in large scale, so it can improve the reliability and efficiency of the grid. We plan to implement smart microgrid system at Sekolah Tinggi Teknik PLN as a pilot project. Before the pilot project start, the feasibility study must be conducted. In this feasibility study, the renewable energy resources and load characteristic at the site will be measured. Then the technical aspect of this feasibility study will be analyzed. This paper explains that analysis of ths feasibility study.

  6. Penggunaan Teknik Obat dan Permasalahan Blokade Epidural di Wilayah Jawa Barat pada Tahun 2015

    Directory of Open Access Journals (Sweden)

    Muhammad Ibnu

    2017-12-01

    Full Text Available Blokade epidural merupakan salah satu jenis anestesi regional yang memiliki rentang implikasi lebih luas dibanding dengan blokade spinal. Perbedaan teknik maupun rejimen obat untuk blokade epidural meningkat seiring dengan meningkatnya ketertarikan di bidang anestesi regional dikarenakan teknik anestesi regional memberikan efek analgesi yang efektif tanpa memengaruhi kesadaran pasien dan meningkatkan kenyamanan pasien. Tujuan penelitian ini mencari data mengenai penggunaan, teknik, rejimen obat, dan permasalahan yang dialami oleh dokter anestesi di Jawa Barat dalam melakukan blokade epidural. Penelitian ini dilakukan pada bulan Agustus hingga September 2016 di Departemen Anestesiologi dan Terapi Intensif Rumah Sakit Dr. Hasan Sadikin Bandung. Penelitian ini bersifat deskriptif dengan pengambilan data menggunakan kuesioner dan pendekatan cross sectional. Kuesioner dikirimkan kepada 120 dokter spesialis anestesi di Jawa Barat melalui jasa pos dan 30 kuesioner diberikan langsung kepada dokter spesialis anestesi yang bekerja di Rumah Sakit Dr. Hasan Sadikin Bandung. Angka respons yang didapatkan sebesar 47,3%. Hasil penelitian ini didapatkan dokter spesialis anestesi yang masih melakukan blokade epidural pada tahun 2015 sebesar 73,2%, teknik penusukan yang paling banyak dilakukan adalah pendekatan midline sebesar 73%, dan identifikasi rongga epidural paling banyak dengan pendekatan lost of resistance sebesar 80,7%. Obat anestesi lokal yang paling banyak digunakan untuk blokade epidural adalah bupivakain sebesar 95,9%. Adjuvan yang paling banyak digunakan adalah fentanil sebesar 92,3%. Permasalahan yang berkaitan dalam pelaksanaan tindakan blokade epidural pada tahun 2015 paling banyak adalah permasalahan staf di ruangan dalam membantu menangani pasien dengan epidural, yaitu sebesar 38,03%. Epidural Blockade Administration Technique and Issues in West Java in 2015 Epidural blockade is one of the regional anesthesia techniques with wider implication

  7. Perawatan Crossbite Posterior pada Maloklusi Angle Klas III dengan Alat Ortodontik Cekat Teknik Begg

    Directory of Open Access Journals (Sweden)

    Trio Wijayanto

    2011-12-01

    Full Text Available Latar Belakang: Crossbite posterior merupakan hubungan abnormal dari gigi-gigi posterior secara bukolingual pada rahang atas atau bawah pada saat kedua lengkung gigi berada dalam oklusi sentrik yang dapat terjadi pada satu atau kedua sisi rahang. Posterior crossbite adalah maloklusi yang paling sering muncul pada masa gigi susu dan awal gigi bercampur. Tujuan Perawatan: mengoreksi crossbite posterior dan mengembalikan fungsi pengunyahan yang baik. Kasus: Perempuan 20 tahun dengan maloklusi Angle klas III disertai crossbite posterior kanan, crowding rahang atas dan bawah. Penanganan: menggunakan alat cekat teknik Begg dengan pencabutan gigi premolar I rahang atas kiri, kedua premolar I rahang bawah, cross elastik, toe-in, dan toe out digunakan untuk koreksi crossbite. Kesimpulan: Perawatan crossbite posterior dengan teknik Begg menunjukkan hasil yang cukup memuaskan. Prognatik mandibula berkurang, crossbite terkoreksi, overjet normal, overbite normal, dan fungsi pengunyahan menjadi lebih baik.   Background: Posterior crossbite is defined as any abnormal bucal-lingual relations between posterior teeth of upper and lower jaw in centric occlusion which can occur in one side only or both. Posterior crossbite is one of the most prevalent malocclusion in primary and early mixed dentition. Purpose: to correct posterior and restore normal mastication. Case: 20 years old woman with Angle’s class II accompanied by posterior crossbite on the right side and crowding in anterior segment of upper and lower jaw. Management: using the Begg fixed appliance techniques with the extraction of upper left, and two lower first premolars. Cross elastic along with toe in and toe out on the main wire was used to correct posterior crossbite. Conclusion: Posterior crossbite treatment with Begg technique showed satisfactory results. Prognatism mandibula had reduced, regained normal overjet and overbite, and restored good mastication.

  8. Teknik Stimulasi dalam Pendidikan Karakter Anak Usia Dini melalui Lirik Lagu Dolanan

    Directory of Open Access Journals (Sweden)

    Ana Rosmiati

    2014-11-01

    Full Text Available Media musik melalui lirik lagu dolanan anak dapat membantu pembentukan karakater padaanak usia dini. Anak-anak dapat merasakan kehadiran musik sebagai sarana untuk menemani aktivitasdalam bermain. Teknik stimulasi melalui media musik ternyata memiliki dampak positif dalamperkembangan pembentukan emosional anak. Anak-anak bisa terkontrol emosinya dari kebiasaanyang tidak baik. Penelitian ini memakai teknik stimulasi melalui pemaknaan lirik lagu dolanan anakyang dapat membentuk karakter anak pada usia dini. Penelitian ini menggunakan metode deskriptifkualitatif yang mendeskripsikan secara sistematis, faktual dan akurat mengenai fakta-fakta, sifat, sertahubungan antara fenomena yang diselidiki. Penelitian ini mengidentifikasikan contoh pemaknaanlagu dolanan anak yang dapat membantu dalam pembentukan karakter pada anak-usia dini. Anakdapat menggali nilai-nilai kehidupan dari makna pada lirik lagu dolanan berupa nilai pendidikan,pengetahuan, religius, sosial, dan budaya. The Stimulation Technique on the Character Education of Early Age Children through theLyrics of Children’s Song. The music media through the children’s song lyrics can help building the childrencharacter of the early age children. Children can feel the presence of the music as the media for accompanyingthe children’s play activities. The stimulation technique through the music media, in fact, has the positiveimpact in developing the children emotional building. The children are able to control their emotion awayfrom the bad habits. The aim of the research is to find the appropriate stimulation technique through theunderstanding of the children’s song lyrics which can be used to build children character in the early age.This research uses a qualitative descriptive method describing systematic, factual, and accurate informationon the facts, nature, and the relationship between the phenomena investigated. The result of the researchhas been identified by some examples of

  9. 76 FR 78180 - Proposed Modification of Class E Airspace; Douglas, AZ

    Science.gov (United States)

    2011-12-16

    ...-1313; Airspace Docket No. 11-AWP-17] Proposed Modification of Class E Airspace; Douglas, AZ AGENCY... action proposes to modify Class E airspace at Bisbee Douglas International Airport, Douglas, AZ... feet above the surface at Douglas, AZ. Additional controlled airspace is necessary to accommodate...

  10. 75 FR 883 - Environmental Impact Statement; Maricopa County, AZ

    Science.gov (United States)

    2010-01-06

    ...; Maricopa County, AZ AGENCY: Federal Highway Administration (FHWA), DOT. ACTION: Notice of Intent. SUMMARY...: (602) 382-8998, e-mail: [email protected] SUPPLEMENTARY INFORMATION: The FHWA, in cooperation with the... reasonable alternatives will be considered including: (1) Taking no action; (2) using alternate travel modes...

  11. Mixer pump test plan for double shell tank AZ-101

    International Nuclear Information System (INIS)

    STAEHR, T.W.

    1999-01-01

    Mixer pump systems have been chosen as the method for retrieval of tank wastes contained in double shell tanks at Hanford. This document describes the plan for testing and demonstrating the ability of two 300 hp mixer pumps to mobilize waste in tank AZ-101. The mixer pumps, equipment and instrumentation to monitor the test were installed by Project W-151

  12. 75 FR 81190 - Television Broadcasting Services; Yuma, AZ

    Science.gov (United States)

    2010-12-27

    ... FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 73 [DA 10-2365; MB Docket No. 02-151; RM-10453] Television Broadcasting Services; Yuma, AZ AGENCY: Federal Communications Commission. ACTION: Dismissal. SUMMARY: The Commission dismisses the petition for rulemaking filed by Arizona Western College, requesting...

  13. User Manual for the AZ-101 Data Acquisition System (AS-101 DAS)

    Energy Technology Data Exchange (ETDEWEB)

    BRAYTON, D.D.

    2000-02-17

    User manual for the TK AZ-101 Waste Retrieval System Data Acquisition System. The purpose of this document is to describe use of the AZ-101 Data Acquisition System (AZ-101 DAS). The AZ-101 DAS is provided to fulfill the requirements for data collection and monitoring as defined in Letters of Instruction (LOI) from Numatec Hanford Corporation (NHC) to Fluor Federal Services (FFS). For a complete description of the system, including design, please refer to the AZ-101 DAS System Description document, RPP-5572.

  14. User Manual for the AZ-101 Data Acquisition System (AS-101 DAS)

    International Nuclear Information System (INIS)

    BRAYTON, D.D.

    2000-01-01

    User manual for the TK AZ-101 Waste Retrieval System Data Acquisition System. The purpose of this document is to describe use of the AZ-101 Data Acquisition System (AZ-101 DAS). The AZ-101 DAS is provided to fulfill the requirements for data collection and monitoring as defined in Letters of Instruction (LOI) from Numatec Hanford Corporation (NHC) to Fluor Federal Services (FFS). For a complete description of the system, including design, please refer to the AZ-101 DAS System Description document, RPP-5572

  15. Pengaruh Strategi SQ4R Tipe Bantuan Multimedia vs Buku Teks, Pengetahuan Awal, Gaya Belajar Kolb terhadap Hasil Belajar Bahasa Inggris Teknik

    OpenAIRE

    Meiti Leatemia

    2014-01-01

    Penelitian ini bertujuan menyelidiki pengaruh strategi SQ4R tipe bantuan multimedia versus buku teks, pengetahuan awal dan gaya belajar terhadap hasil belajar bahasa Inggris Teknik. Subjek penelitian adalah 96 mahasiswa  Teknik Sipil dan Mesin Politeknik Negeri Ambon tahun akademik 2011-2012. Desain eksperimen menggunakan kuasi versi  factorial  (2 x 2 x 2) pre test-post test non-equivalent control group design. Analisis data menggunakan statistik Three Ways ANOVA. Pengujian hipotesis dilakuk...

  16. Influence of artificial biological fluid composition on the biocorrosion of potential orthopedic Mg-Ca, AZ31, AZ91 alloys

    International Nuclear Information System (INIS)

    Gu, X N; Zheng, Y F; Chen, L J

    2009-01-01

    The electrochemical behavior of potential orthopedic Mg-Ca, AZ31 and AZ91 alloys was studied in Hank's solution, Dulbecco's Modified Eagle's Medium (DMEM) and serum-containing medium (DMEM adding 10% fetal bovine serum (DMEM+FBS)) over a 7 day immersion period. The biocorrosion of the above three alloys for various immersion time intervals was investigated by linear polarization and electrochemical impedance spectroscopy (EIS). After 7 day immersion, potentiodynamic polarization tests were carried out and the surface morphologies of experimental samples were examined by scanning electron microscopy (SEM) observation complemented by energy-disperse spectrometer (EDS) analysis. It was shown that the corrosion of magnesium alloys was influenced by the composition of the solution. The results indicated that chloride ion could reduce the corrosion resistance and the hydrocarbonate ions could induce rapid surface passivation. The adsorbed amino acid on the experimental magnesium alloys' surface increased their polarization resistance and reduced current densities. The influence of the serum protein on corrosion was found to be associated with the magnesium alloy compositions. A Mg-Ca alloy exhibited an increased corrosion rate in the presence of serum protein. An AZ31 alloy showed an increased corrosion rate in DMEM+FBS in the initial 3 day immersion and the corrosion rate decreased thereafter. An AZ91 alloy, with high Al content, showed a reduced corrosion rate with the addition of FBS into DMEM.

  17. Influence of artificial biological fluid composition on the biocorrosion of potential orthopedic Mg-Ca, AZ31, AZ91 alloys.

    Science.gov (United States)

    Gu, X N; Zheng, Y F; Chen, L J

    2009-12-01

    The electrochemical behavior of potential orthopedic Mg-Ca, AZ31 and AZ91 alloys was studied in Hank's solution, Dulbecco's Modified Eagle's Medium (DMEM) and serum-containing medium (DMEM adding 10% fetal bovine serum (DMEM+FBS)) over a 7 day immersion period. The biocorrosion of the above three alloys for various immersion time intervals was investigated by linear polarization and electrochemical impedance spectroscopy (EIS). After 7 day immersion, potentiodynamic polarization tests were carried out and the surface morphologies of experimental samples were examined by scanning electron microscopy (SEM) observation complemented by energy-disperse spectrometer (EDS) analysis. It was shown that the corrosion of magnesium alloys was influenced by the composition of the solution. The results indicated that chloride ion could reduce the corrosion resistance and the hydrocarbonate ions could induce rapid surface passivation. The adsorbed amino acid on the experimental magnesium alloys' surface increased their polarization resistance and reduced current densities. The influence of the serum protein on corrosion was found to be associated with the magnesium alloy compositions. A Mg-Ca alloy exhibited an increased corrosion rate in the presence of serum protein. An AZ31 alloy showed an increased corrosion rate in DMEM+FBS in the initial 3 day immersion and the corrosion rate decreased thereafter. An AZ91 alloy, with high Al content, showed a reduced corrosion rate with the addition of FBS into DMEM.

  18. Influence of artificial biological fluid composition on the biocorrosion of potential orthopedic Mg-Ca, AZ31, AZ91 alloys

    Energy Technology Data Exchange (ETDEWEB)

    Gu, X N; Zheng, Y F [State Key Laboratory for Turbulence and Complex System and Department of Advanced Materials and Nanotechnology, College of Engineering, Peking University, Beijing 100871 (China); Chen, L J, E-mail: yfzheng@pku.edu.c [School of Material Science and Engineering, Shengyang University of Technology, Shenyang 110023 (China)

    2009-12-15

    The electrochemical behavior of potential orthopedic Mg-Ca, AZ31 and AZ91 alloys was studied in Hank's solution, Dulbecco's Modified Eagle's Medium (DMEM) and serum-containing medium (DMEM adding 10% fetal bovine serum (DMEM+FBS)) over a 7 day immersion period. The biocorrosion of the above three alloys for various immersion time intervals was investigated by linear polarization and electrochemical impedance spectroscopy (EIS). After 7 day immersion, potentiodynamic polarization tests were carried out and the surface morphologies of experimental samples were examined by scanning electron microscopy (SEM) observation complemented by energy-disperse spectrometer (EDS) analysis. It was shown that the corrosion of magnesium alloys was influenced by the composition of the solution. The results indicated that chloride ion could reduce the corrosion resistance and the hydrocarbonate ions could induce rapid surface passivation. The adsorbed amino acid on the experimental magnesium alloys' surface increased their polarization resistance and reduced current densities. The influence of the serum protein on corrosion was found to be associated with the magnesium alloy compositions. A Mg-Ca alloy exhibited an increased corrosion rate in the presence of serum protein. An AZ31 alloy showed an increased corrosion rate in DMEM+FBS in the initial 3 day immersion and the corrosion rate decreased thereafter. An AZ91 alloy, with high Al content, showed a reduced corrosion rate with the addition of FBS into DMEM.

  19. Penerapan Dizcretization dan Teknik Bagging Untuk Meningkatkan Akurasi Klasifikasi Berbasis Ensemble pada Algoritma C4.5 dalam Mendiagnosa Diabetes

    Directory of Open Access Journals (Sweden)

    Mirqotussa’adah Mirqotussa’adah

    2017-08-01

    Full Text Available Pada bidang kesehatan, data mining dapat dimanfaatkan untuk memprediksi suatu penyakit dari data rekam medis pasien, diantaranya diabetes. Ada beberapa model data mining salah satunya klasifikasi. Di bidang klasifikasi,  ada banyak cabang yang berkembang yaitu pohon keputusan (decision tree. Salah satu decision tree yang populer adalah C4.5. Dalam riset ini, data yang digunakan adalah pima indian diabetes dataset yang diambil dari UCI repository of machine learning. Pada dataset ini seluruh atributnya bertipe numerik yang bersifat continuous dan untuk menangani data continuous digunakan discretization. Akurasi sangat penting dalam pengklasifikasian, ensemble method adalah metode yang digunakan untuk meningkatkan akurasi algoritma klasifikasi dengan membangun beberapa classifier dari data training. Dari hasil penelitian, dengan menerapkan discretization dan teknik bagging untuk klasifikasi berbasis ensemble pada algoritma C4.5 dapat meningkatkan akurasi sebesar 6,26%. Dengan akurasi awal 68,61%, setelah diterapkan discretization dan teknik bagging menjadi 74,87%.

  20. PENGGUNAAN TEKNIK KEAMANAN PADA JARINGAN SERAT OPTIK DENGAN METODE ANTI-JAMMING DAN STEGANOGRAFI MENGGUNAKAN MODUL OPTISYSTEM

    Directory of Open Access Journals (Sweden)

    Mia Rosmiati

    2017-02-01

    Full Text Available Serat optic merupakan media transmisi yang dapat menghantarkan informasi dalam bentuk cahaya. digunakannya cahaya sebagai media penghantaran informasi membuat media ini dapat menghantarkan informasi dengan kapasitas besar dalam waktu yang sangat singkat. Sehingga saat ini serat optic banyak digunakan dalam Telekomunikasi. jaringan serat optic ini harus disertai dengan teknik keamanan yang handal dalam proses transmisi informasinya, karena jika terjadi  penyerangan  dalam jaringan yang serat optic maka data yang akan diterima oleh receiver akan jauh berbeda dengan data yang dikirim transmitter. Sehingga hal ini sangat fatal jika informasi yang dikirimkan memiliki tingkat kerahasiaan yang sangat  tinggi seperti informasi keamanan Negara. Adapun metode yang dapat digunakan dalam pengamanan jaringan serat optic adalah metode steganography dan metode anti-jamming. Dari percobaan yang telah dilakukan terlihat bahwa teknik steganography memiliki tingkat kehandalan yang lebih baik jika dibandingkan dengan metode anti-jamming dengan  nilai BER untuk metode steganography adalah 1.91219e-077.

  1. METODE DAN TEKNIK BIMBINGAN KONSELING ISLAMI UNTUK MEMBANTU PERMASALAHAN PADA ANAK-ANAK

    Directory of Open Access Journals (Sweden)

    Atikah Atikah

    2015-08-01

    Full Text Available Perkembangan pada usia anak akan mempengaruhi perkembangan pada fase berikutnya.  Jika  anak usia dini dalam pengasuhan yang benar dan sesuai dengan karakter anak maka akan mampu menghadapi tugas perkembangan (task development berikutnya, dan akan sebaliknya ketika anak usia dini dalam pengasuhan yang salah atau perlakuan yang salah pada anak (child abuse. Sehingga dibutuhkan pemahaman tentang usia anak,  lengkap dengan karakteristik-kebutuhan-permasalahan untuk membantu tumbuh kembang anak agar optimal sesuai dengan tahapan kemampuan yang harus dimiliki anak. Cara-cara membantu masalah yang sering dialami anak-anak disesuaikan dengan tahapan usia. Ciri khas pada anak adalah bermain dan bergembira, sehingga anak-anak dapat menyelesaikan masalah yang sering muncul dengan suasana senang dan ceria. Memahamkan anak-anak tentang penyelesaian masalah juga diperlukan agar siap menghadapi permasalahan dengan kemampuan yang dimiliki. Salah satu teknik dalam metode kelompok yaitu karyawisata. Dengan mengunjungi tempat-tempat wisata,  memberi kesempatan pada anak-anak berganti situasi (rutinitas ke obyek wisata untuk mengatasi masalah dengan tetap bersenang-senang bermain. Sehingga permainan di tempat obyek wisata akan memberikan dampak kesegaran fisik  dan beban- beban masalah yang terjadi terbantukan dengan mengalihkan ke permainan yang di setting untuk membantu pemecahan masalah. Dan teknik-teknik bimbingan konseling Islam yang lainnya dapat digunakan untuk menyelesaikan sesuai dengan berbagai macam permasalahan. kata kunci: Metode Bimbingan  Konseling, Konseling Islami, Permasalahan Anak METHODS AND TECHNIQUES TO HELP THE ISLAMIC GUIDANCE COUNSELING PROBLEMS IN  CHILDREN. Development of the child’s age will affect the development of the next phase. If early childhood in the care of the correct and in accordance with the character of the child will be able to face the developmental task(taskdevelopmentnext,  and will instead when early

  2. AKUISISI KOMPETENSI SISWA PADA KOMPETENSI KEAHLIAN TEKNIK INSTALASI TENAGA LISTRIK MELALUI PRAKTIK KERJA INDUSTRI

    Directory of Open Access Journals (Sweden)

    Mohammad Fatkhurrokhman

    2016-08-01

    Full Text Available Penelitian ini bertujuan untuk mengungkap akuisisi kompetensi keahlian teknik instalasi tenaga listrik pada siswa sekolah menengah kejuruan untuk memperoleh kompetensi melalui kegiatan praktik kerja industri. Penelitian ini dilaksanakan dengan pendekatan kualitatif jenis studi kasus. Informan pada penelitian ini adalah pembimbing industri, pembimbing siswa dari sekolah, dan siswa peserta praktik kerja industri. Pengumpulan data dilakukan melalui wawancara dan observasi. Teknik analisis data dilaksanakan dengan model interaktif Miles & Huberman, meliputi pengumpulan data, data condensation, penyajian data, verifikasi, dan penarikan kesimpulan. Hasil penelitian ini dapat disimpulkan bahwa: (1 proses yang dilalui siswa dalam memperoleh kompetensi dapat dilihat dari tiga aspek, yaitu: aspek pengetahuan (mengamati, diskusi, dan mencoba, aspek keterampilan (siswa mengamati, pembimbing memberikan contoh, siswa mendiagnosis permasalahan, siswa mengerjakan, siswa bertanya, dan pembimbing mengecek hasil pekerjaan dan aspek sikap (tuntutan, adopsi, dan terbiasa; dan (2 kompetensi yang diperoleh siswa dapat dilihat dari tiga aspek, yaitu: aspek pengetahuan (dunia kerja, bersosialisasi, melayani pelanggan, bekerja dalam tim, dan pengetahuan di bidang ketenagalistrikan, aspek keterampilan (bersosialisasi, melayani pelanggan, bekerja dalam tim, dan keterampilan dibidang keahlian ketenagalistrikan, dan aspek sikap (disiplin, bekerja keras, tanggung jawab, minat bekerja, dan minat berwirausaha. Kata kunci: akuisisi, kompetensi instalasi listrik, hasil belajar, praktik kerja industri THE ACQUISITION OF ELECTRIC POWER INSTALLATION COMPETENCIES OF VOCATIONAL HIGH SCHOOL STUDENTS THROUGH INDUSTRIAL WORK PRACTICE Abstract This research aimed to reveal the acquisition electric power installation competencies of vocational high school students through industrial work practice. The research used the qualitative case study approach. The informants of this research were

  3. Sistem Pakar Diagnosis Hama dan Penyakit Tanaman Hortikultura dengan Teknik Inferensi Forward dan Backward Chaining

    Directory of Open Access Journals (Sweden)

    Ginanjar Wiro Sasmito

    2017-05-01

    Full Text Available One of the obstacles to doing cultivation of horticulture plant is to overcome pest and disease. Pest and disease attack can decrease productivity and even causes harvest fail that influence toward one of income sources the country. Therefore the diagnose on pest and disease must be done fastly and accurately. One of horticulture plant is red onion and chili plant. An expert system is offered as the second choice after expert on consultation. Using Expert System Development Life Cycle (ESDLC method, combination inference engine of and backward chaining for diagnosing pest and horticulture plant disease created as giving the solution. The technique of reasoning used in this research is the rule-based. The result of the research is an application that can be used to diagnosis pest and disease horticulture plant, that are red onion and chili. By this application, the farmer can determine quick action should be taken if the farm pests and diseases, without waiting for a consultation with an expert to do the handling. The application result also could be a learning system to the farmer about pest and disease horticulture plant. Salah satu kendala melakukan budidaya tanaman hortikultura adalah dalam mengatasi hama dan penyakit. Serangan hama dan penyakit dapat menurunkan produktivitas dan bahkan menyebabkan gagal panen yang berpengaruh terhadap salah satu sumber devisa negara. Oleh karena itu, diagnosis terhadap hama dan penyakit harus dilakukan dengan cepat dan akurat. Tanaman hortikultura tersebut salah satunya adalah bawang merah dan cabai. Sistem pakar dihadirkan sebagai pilihan kedua setelah pakar dalam melakukan konsultasi. Dengan menggunakan metode Expert System Development Life Cycle (ESDLC, penggabungan teknik inferensi forward dan backward chaining untuk diagnosis hama dan penyakit tanaman hortikultura dibuat sebagai solusi atas permasalahan yang ada. Teknik penalaran yang digunakan dalam penelitian ini yakni rule-based reasoning. Hasil

  4. Deteksi Daging Babi Pada Produk Bakso di Pusat Kota Salatiga Menggunakan Teknik Polymerase Chain Reaction

    Directory of Open Access Journals (Sweden)

    Fidia Fibriana

    2012-09-01

    Full Text Available Teknik PCR mempunyai kemampuan yang sensitif untuk deteksi keberadaan daging babi di dalam daging segar maupun produk olahan yang dicampur dengan bahan lain. Tujuan penelitian ini untuk mengetahui apakah produk bakso yang dijajakan di pusat kota Salatiga mengandung daging babi. Teknik stratified random sampling digunakan untuk mengambil sampel bakso yang dijajakan 13 warung bakso dari 25 warung bakso yang tersebar di pusat Kota Salatiga. Isolasi dan purifikasi DNA sampel bakso, daging sapi, dan daging babi menggunakan metode isolasi DNA jaringan hewan. DNA hasil isolasi dilanjutkan proses PCR menggunakan primer p14 untuk mengamplifikasi lokus PRE-1 pada genom babi. Proses amplifikasi DNA dengan program denaturasi awal pada suhu 93 °C selama 2 menit, diikuti 45 siklus terdiri atas denaturasi 93 °C selama 1 menit, annealing 62 °C selama 30 detik, ekstensi 72 °C selama 1 menit, kemudian diakhiri ekstensi 72 °C selama 2 menit. Produk PCR yang diharapkan muncul berukuran 481bp. Hasil elektroforesis gel agarose 1,2% pada produk PCR menunjukkan adanya pita DNA spesifik berukuran 481 bp pada daging babi dan sampel bakso nomor tiga belas, sehingga disimpulkan warung bakso nomor tiga belas produk baksonya mengandung daging babi.PCR technique has the ability to be sensitive to the detection of the presence of pork in fresh meat and processed products are mixed with other materials. The aim of this research to determine whether the product meatballs are sold in downtown Salatiga containing pork. Stratified random sampling technique is used to take samples of meatballs stall which sold 13 of the 25 meatballs stalls in the Salatiga City centre. Isolation and purification of DNA samples of meatballs, beef, and pork using DNA isolation method of animal tissue. DNA isolation results continue the process of PCR using primers to amplify p14 locus PRE-1 in the pig genome. DNA amplification process with initial denaturation program at a temperature of 93

  5. PRODUK BENANG SUTRA BERKUALITAS MELALUI TEKNIK SERIKULTUR DENGAN PAKAN YANG DIKEMBANGKAN SECARA IN VITRO

    Directory of Open Access Journals (Sweden)

    Faradilla Faradilla

    2018-01-01

    Full Text Available Samarinda woven sarong is typical sarong of Samarinda. This sarong is still using silk spun silk raw material imported from Tiongkok. The development of aquaculture is needed to obtain local silk threads in order to help to reduce production costs in the samarinda silk industry. The high quality mulberry plants are needed to support silkworm cultivation (sericulture. The qualified mulberry plants are obtained by in vitro culture techniques. The objective of this study is to obtain mulberry leaf (Morus Sp free from disease, uniform, and to obtain quality silk threads through sericulture techniques with feeds that were propagated in vitro. The research stages consist of sterilization, Murashige and Skoog (MS media, sub culture, observation of data analysis fund. The design used is Completely Randomized Design with single factor, ie BAP concentration (control, 0.5 mg / l, 1 mg / l and 2 mg / l. Each treatment is repeated 8 times. The results showed that administration of ZPT 2 mg / l at age 4 MST gives the best response for all observed variables. The use of ZPT BAP with various concentrations produces the germination rate, shoot height, number of shoots and number of different leaves. All treatments are unsuccessful in inducing roots. Keywords: in vitro; Murbei; Sericulture Sarung tenun samarinda adalah sarung khas kota Samarinda. Sarung ini masih menggunakan bahan baku sutera jenis spun silk yang diimpor dari Tiongkok. Pengembangan serikultur diperlukan untuk mendapatkan benang sutera lokal. Sehingga membantu mengurangi biaya produksi dalam industri persuteraan samarinda. Tanaman murbei yang berkualitas diperlukan untuk menunjang budidaya ulat sutera (serikultur. Tanaman murbei yang berkualitas diperoleh dengan teknik kultur in vitro. Tujuan penelitian adalah memperoleh daun murbei (Morus Sp yang bebas penyakit dan seragam serta memperoleh benang sutera berkualitas melalui teknik serikultur dengan pakan yan diperbanyak secara in vitro. Tahapan

  6. MENGURANGI PERILAKU SISWA TIDAK TEGAS MELALUI PENDEKATAN REBT DENGAN TEKNIK ASSERTIVE TRAINING

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    Tri Jayanti

    2012-11-01

    Full Text Available Penelitian ini bertujuan untuk mengurangi perilaku siswa tidak tegas terhadap te-man-teman sekelasnya yang tidak bersahabat melalui pendekatan Rational Emo-tive Behavior Therapy (REBT dengan teknik assertive training. Penelitian ini dilak-sanakan dengan menggunakan metode kombinasi (mixed methods dengan modelconcurrent embedded (campuran tidak berimbang. Subyek dalam penelitian iniadalah 3 siswa kelas VIII di SMP Teuku Umar Semarang yang berperilaku tidak te-gas terhadap teman-teman sekelasnya yang tidak bersahabat. Metode pengumpulandata yang digunakan adalah wawancara, observasi, dan dokumentasi. Teknik anali-sis data yang digunakan adalah analisis data interaktif Miles and Huberman, sertaanalisis deskriptif persentase. Hasil penelitian adalah ketiga klien mampu men-gubah keyakinan irrasional menjadi rasional, sehingga ketiga klien mampu men-gubah perilaku tidak tegas menjadi perilaku tegas terhadap teman-teman sekelasnyayang tidak bersahabat. Perilaku tidak tegas ketiga klien berkurang dari frekuensi ser-ing menjadi jarang. Dengan ketiga klien berperilaku asertif terjalin hubungan baikantara ketiga klien dengan teman-teman sekelasnya yang tidak bersahabat. Simpu-lan dari penelitian ini adalah perilaku siswa tidak tegas terhadap teman-teman seke-lasnya yang tidak bersahabat dapat dikurangi melalui pendekatan REBT denganteknik assertive training The purpose of the research is to decrease the students non assertive behavior toward their notfriendly classmate through the Rational Emotive Behavior Therapy (REBT approach withthe assertive training technique. This research uses the mixed methods with the concurrentembedded design. The Subject of this research is the students at eighth grade of Junior HighSchool Teuku Umar Semarang that consist of three students who had non assertive behaviortoward their not friendly classmate. The methods for collecting data are interview, observation,and documentation. The data analysis technique uses the analysis

  7. Pengaruh Bimbingan Kelompok Terhadap Pemahaman Agresivitas pada Siswa Melalui Teknik Role Playing di SMA Negeri 1 Sumber Rembang

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    Krisna Murjiatik

    2015-04-01

    Full Text Available Tujuan penelitian ini adalah untuk mengetahui apakah layanan bimbingan kelompok dengan teknik role playing dapat berpengaruh terhadap pemahaman agresivitas siswa. Penelitian ini termasuk dalam jenis penelitian eksperimen. Desain yang digunakan adalah (quasi-experimental, serta pola eksperimen yang digunakan adalah pre-test and post-test. Teknik pengambilan sampel menggunakan purposive sampling yang berjumlah 15 siswa terdiri dari 3 siswa berkriteria rendah dan 12 siswa berkriteria sedang. Metode pengumpulan data menggunakan metode summated ratings atau lebih terkenal dengan model skala Likert yang digunakan sebelum dan sesudah pemberian bimbingan kelompok. Teknik analisis data menggunakan uji Wilcoxon. Hasil pre-test pemahaman agresivitas siswa kategori sedang (48,65 %. Setelah diberikan treatment berupa layanan bimbingan kelompok dengan teknik role palying, hasil post-test pemahaman agresivitas siswa kategori rendah (35,52 %. Hasil penelitian menunjukkan adanya pengaruh pemahaman agresivitas siswa dalam bimbingan kelompok pada siswa sebesar 13,13%. Dengan demikian pemahaman agresivitas siswa dapat dipahami melalui layanan bimbingan kelompok dengan teknik role playing. The purpose of this study was to determine whether counseling services group with role playing techniques can affect the students' understanding of aggressiveness. This research included in this type of research experiments. The design used is (quasi-experimental, as well as the experimental pattern used is the pre-test and post-test. The sampling technique used purposive sampling consisted of 15 students from low berkriteria 3 students and 12 students berkriteria being. Methods of data collection methods Summated ratings or better known as Likert scale models are used before and after the administration of group counseling. Data were analyzed using the Wilcoxon test. The pre-test students' understanding of the aggressiveness of the medium category (48.65%. After being given a

  8. Characterization of mussel H2A.Z.2: a new H2A.Z variant preferentially expressed in germinal tissues from Mytilus.

    Science.gov (United States)

    Rivera-Casas, Ciro; González-Romero, Rodrigo; Vizoso-Vazquez, Ángel; Cheema, Manjinder S; Cerdán, M Esperanza; Méndez, Josefina; Ausió, Juan; Eirin-Lopez, Jose M

    2016-10-01

    Histones are the fundamental constituents of the eukaryotic chromatin, facilitating the physical organization of DNA in chromosomes and participating in the regulation of its metabolism. The H2A family displays the largest number of variants among core histones, including the renowned H2A.X, macroH2A, H2A.B (Bbd), and H2A.Z. This latter variant is especially interesting because of its regulatory role and its differentiation into 2 functionally divergent variants (H2A.Z.1 and H2A.Z.2), further specializing the structure and function of vertebrate chromatin. In the present work we describe, for the first time, the presence of a second H2A.Z variant (H2A.Z.2) in the genome of a non-vertebrate animal, the mussel Mytilus. The molecular and evolutionary characterization of mussel H2A.Z.1 and H2A.Z.2 histones is consistent with their functional specialization, supported on sequence divergence at promoter and coding regions as well as on varying gene expression patterns. More precisely, the expression of H2A.Z.2 transcripts in gonadal tissue and its potential upregulation in response to genotoxic stress might be mirroring the specialization of this variant in DNA repair. Overall, the findings presented in this work complement recent reports describing the widespread presence of other histone variants across eukaryotes, supporting an ancestral origin and conserved role for histone variants in chromatin.

  9. Test Excavations at Painted Rock Reservoir: Sites AZ Z:1:7, AZ Z:1:8, and AZ S:16:36.

    Science.gov (United States)

    1981-11-01

    were dehydrated, trimmed to 12-mm squares, and 77 78 placed in catalyzed (0.05-percent benzoyl peroxide), deinhibited acrylic monomer (50-percent methyl ...refrigeration for 72 hours in partially polymerized ethyl- methyl methacrylate. The methacrylate was polymerized at 50 degrees C and 50 p.s.i. nitrogen...pollen types from fill of Feature 10, AZ Z:l:8 Pollen Type Percent Pinus spp. 0.5 Cheno-Am 92.0 Gramineae 2.0 Ambrosia spp. 0.5 Malvaceae 0.5 Zea spp. 2.0

  10. Pembuatan Virtual Kampus Sistem Komputer Fakultas Teknik Universitas Diponegoro Menggunakan Jaringan Lokal Berbasis VRML

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    Hendra Taufiq Oktafianto

    2015-01-01

    Full Text Available Dalam bidang informasi banyak cara dalam menginformasikan data, baik secara tertulis, gambar, suara, gambar dan suara. Saat ini banyak dikembangkan teknologi dengan menggunakan metode visual yang interaktif, seperti dunia virtual yang membuat seolah-olah informasi tersebut di dapat sesuai dengan pengalaman memasuki daerah yang di lihat pada dunia virtual tersebut. Metode tersebut adalah pengembangan teknologi virtual reality yang dibuat dengan menggunakan 3DS Max sebagai software untuk menghasilkan gambar yang menarik. Pengaplikasian yang dikembangkan dengan media web dimana setiap pengguna lebih mudah dalam dalam menggunakan aplikasi tersebut. Metode pengambangan yang dirancang adalah memadukan teknologi virtual reality dengan web. Dimana aplikasi tersebut terdapat didalam tampilan web yang didukun basis data untuk mempermudah aktor admin dalam mengolah data. Pada browser yang digunakan akan di pasang plug-in cortona3d agar dapat menampilkan file ekstensi tiga dimensi yang dapat di tampilkan browser. Hasil dari pembuatan aplikasi ini adalah terancangnya sebuah aplikasi yang menggunakan teknologi virtual reality modeling language dengan studi kasus Kampus Sistem Komputer Fakultas Teknik Universitas Diponegoro menggunakan jaringan lokal berbasis VRML

  11. TEKNIK ESTIMASI GERAK PENCARIAN PENUH DENGAN AKURASI SETENGAH PIKSEL UNTUK FRAME RATE UP CONVERSION VIDEO

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    ary satya prabhawa

    2014-10-01

    Full Text Available ABSTRAK Saat ini Teknologi video digital banyak digunakan pada aplikasi hiburan, contohnya adalah TV Digital dengan format HD. Dengan frame rate tinggi, pengkodean video akan menghasil laju bit lebih tinggi yaitu sampai 15 – 30 fps. Permasalahannya adalah kapasitas saluran transmisi memiliki kapasitas terbatas. Solusinya adalah menurunkan laju bit dengan menurunkan jumlah frame video ke penerima. Skema ini dikenal dengan Frame Rate Up-Conversion (FRUC video, dimana frame yang di encoder akan direkonstruksi kembali di decoder dengan membangkitkan frame intermediate (FI. FI dibangkitkan dengan teknik Motion Compensation Interpolation (MCI. Terkait dengan metode FRUC, penelitian ini mengajukan skema MCI unidirectional dengan pencarian gerak akurasi setengah piksel. Pada skema ini, sebuah motion vector (MV kandidat akan dicari di frame referensi, proses estimasi gerak dilakukan dengan menambah piksel sisipan diantara piksel eksisting. Sasarannya adalah meningkatkan akurasi MV kandidat. Hasil simulasi menunjukkan bahwa metode yang diajukan lebih baik sampai sebesar masing – masing 3,21 dB dan 3,11 dB pada wilayah pencarian 7 dan 15 piksel dibandingkan dengan metode frame repetition untuk sekuen video foreman dan hall monitor.

  12. PENGENDALIAN KUALITAS PADA RANTAI PASOK SAYURAN SELADA DENGAN TEKNIK BUDIDAYA HIDROPONIK NFT

    Directory of Open Access Journals (Sweden)

    Fristy Yuanita

    2017-07-01

    Full Text Available Tujuan dari penelitian mengenai pengendalian kualitas pada rantai pasok sayuran selada NFT (Nutrient Film Technique adalah untuk melihat kinerja pelaku yang ada dalam rantai pasok sebagai upaya dalam pengendalian kualitas produk dalam bisnis pertanian. Penelitian dilakukan pada PT. Momenta Agrikultura “Amazing Farm” yang berlokasi di Desa Cikahuripan Kampung Cisaroni RT 002/008, Kecamatan Lembang, Kabupaten Bandung Barat, Jawa Barat Indonesia. Desain penelitian yang digunakan dalam penelitian ini adalah desain kualitatif didukung data kuantitatif dengan teknik penelitian yang digunakan adalah studi kasus. Pengambilan sampel yang digunakan adalah metode purposive sampling. Data yang diperoleh adalah data primer dan data sekunder. Analisis data menggunakan analisis deskriptif. Hasil penelitian menunjukkan permasalahan utama adalah kontrak yang tidak memadai serta penanganan yang kasar disebabkan kurangnya pengawasan dan evaluasi kinerja secara rutin, serta pengendalian kualitas proses produksi pada rantai pasok selada dilakukan oleh pemasok dan PT Momenta Agrikultura “Amazing Farm”. Kinerja PT Momenta Agrikultura “Amazing Farm” mendekati empat sigma, yang mana merupakan standar industri Amerika dan melebihi standar kebanyakan industri di Indonesia. Tindakan pada perbaikan dan pengendalian yang diusulkan yaitu pembenahan kontrak, pembagian informasi, perbaikan metode kerja dan mengu-rangi resiko penurunan kualitas dengan Standard Operating Procedure (SOP pada Packing House agar lebih steril, efektif, dan efisien.

  13. PENERAPAN TEKNIK BAGGING PADA ALGORITMA KLASIFIKASI UNTUK MENGATASI KETIDAKSEIMBANGAN KELAS DATASET MEDIS

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    Rizki Tri Prasetio

    2016-03-01

    para peneliti dari berbagai bidang. Oleh karena itu, sejumlah metode seperti metode sampling, cost-sensitive learning, serta bagging dan boosting, telah diusulkan untuk memecahkan masalah ini. Beberapa dataset medis yang memiliki dua kelas atau binominal mengalami ketidakseimbangan kelas yang menyebabkan kurangnya akurasi pada klasifikasi. Pada penelitian ini diusulkan kombinasi teknik bagging dan algoritma klasifikasi untuk meningkatkan akurasi dari klasifikasi dataset medis. Teknik bagging digunakan untuk menyelesaikan masalah ketidakseimbangan kelas. Metode yang diusulkan diterapkan pada tiga algoritma classifier yaitu, naïve bayes, decision tree dan k-nearest neighbor. Penelitian ini menggunakan lima dataset medis yang didapatkan dari UCI Machine Learning yaitu, breast-cancer, liver-disorder, heart-disease, pima-diabetes dan vertebral column. Hasil penelitian menunjukan bahwa metode yang diusulkan membuat peningkatan yang signifikan pada dua algoritma klasifikasi yaitu decision tree dengan P value of t-Test sebesar 0,0184 dan k-nearest neighbor dengan P value of t-Test sebesar 0,0292, akan tetapi tidak signifikan pada naïve bayes dengan P value of t-Test sebesar 0,9236. Setelah diterapkan teknik bagging pada lima dataset medis, naïve bayes memiliki akurasi paling tinggi untuk dataset breast-cancer sebesar 96,14% dengan AUC sebesar 0,984, heart-disease sebesar 84,44% dengan AUC sebesar 0,911dan pima-diabetes sebesar 74,73% dengan AUC sebesar 0,806. Sedangkan k-nearest neighbor memiliki akurasi yang paling baik untuk dataset liver-disorder sebesar 62,03% dengan AUC sebesar dan 0,632 dan vertebral column dengan akurasi sebesar 82,26% dengan AUC sebesar 0,867. Kata Kunci: teknik ensemble, bagging, ketidakseimbangan kelas, dataset medis.

  14. PENGARUH TEKNIK PENYAYATAN PAHAT MILLING PADA CNC MILLING 3 AXIS TERHADAP TINGKAT KEKASARAN PERMUKAAN BENDA BERKONTUR

    Directory of Open Access Journals (Sweden)

    Irawan Irawan

    2016-06-01

    Full Text Available Dalam perindustrian penggunaan mesin CNC Milling sangat di andalkan untuk mendapatkan hasil yang optimum baik secara kualitas maupun kuantitas. Akan tetapi muncul permasalahan,bagaimana pengaruh perbedaan teknik penyayatan terhadap nilai kekasaran permukaan benda kerja berkontur dalam proses milling CNC. Penelitian ini bertujuan untuk mengetahui pengaruh metode penyayatan pahat milling terhadap kekasaran permukaan benda kerja berkontur yang di hasilkan pada proses freis dengan menggunakan mesin milling CNC - 3Axis Makino S33. Peneliitan ini merancang dan membuat molding Cover stop kontak dikarenakan permukaan produk cover stop kontak memiliki permukaan yang berkontur. Molding ini terdiri dari Core dan Cavity. Benda kerja yang akan di ujicoba adalah bagian Core sebanyak 3 buah. Dalam pengerjaanya benda ujicoba diberikan perlakuan yang sama antara lain, kedalaman pemotongan, kecepatan spindle, dan jenis pahat yang di gunakan, kemudian dari ke 3 benda kerja tersebut masing- masing di tentukan 3 titik pengukuran. Dari hasil pengujian yang di peroleh kemudian dilakukan analisis tabel. Nilai kekasaran permukaan terendah (rata-rata kekasaran 0.899µ m dengan waktu permesinan tercepat (waktu proses 1 jam 08 menit pada penggunaan metode penyayatan 3D offset finishing. Penulis menyarankan agar dalam proses freis menggunakan mesin milling CNC 3Axis Makino S33 pada permukaan benda yang berkontur, untuk mendapatkan nilai kekasaran yang terendah disarankan menggunakan metode penyayatan 3D offset finishing.

  15. FAKTOR-FAKTOR PENGHAMBAT PENGERJAAN TUGAS AKHIR SKRIPSI MAHASISWA PENDIDIKAN TEKNIK OTOMOTIF FT UNY

    Directory of Open Access Journals (Sweden)

    Ibnu Siswanto

    2015-06-01

    Full Text Available Tujuan yang ingin dicapai dalam penelitian ini ialah mengetahui dan mendeskripsikan secara faktual, akurat dan sistematis tentang 1 Implementasi pedoman penulisan tugas akhir skripsi mahasiswa FT UNY di Jurusan PT. Otomotif dan 2 Faktor-faktor yang menjadi penghambat dalam pengerjaan tugas akhir skripsi mahasiswa PT. Otomotif FT UNY Penelitian ini menggunakan pendekatan deskriptif. Objek penelitian ialah Koordinator tugas akhir skripsi, dosen pembimbing, dan mahasiswa PT. Otomotif FT UNY. Pengumpulan data dilakukan dengan wawancara dan dokumentasi. Teknik analisis data yang dipergunakan ialah metode analisis deskriptif.  Hasil penelitian menunjukkan bahwa 1 Implementasi pedoman penulisan tugas akhir skripsi di jurusan PT. Otomotif FT UNY dilakukan dengan pembentukan koordinator tugas akhir skripsi, pembagian tahapan-tahapan pengerjaan skripsi yang terdiri dari pengajuan judul, bimbingan, pengambilan data penelitian, dan ujian TAS sampai dengan pengeluaran nilai TAS. Semua dosen PT. Otomotif FT UNY melaksanakan bimbingan tugas akhir skripsi sesuai dengan pedoman penulisan tugas akhir skripsi. Jurusan PT. Otomotif FT UNY juga melakukan bimbingan klasikal bagi mahasiswa yang akan/sedang mengerjakan tugas akhir skripsi, 2 Faktor-faktor yang menjadi penghambat dalam pengerjaan tugas akhir skripsi yaitu kesulitan dalam menemukan permasalahan yang akan diangkat menjadi judul penelitian, mahasiswa fokus mengerjakan proyek akhir (mahasiswa angkatan 2008 ke bawah, fokus laporan KKN PPL, mengulang banyak mata kuliah, tidak rutin bimbingan dengan dosen, kesulitan dalam menulis karya tulis ilmiah.

  16. POLA PENDANAAN PENYELENGGARAAN PENDIDIKAN SEKOLAH MENENGAH KEJURUAN NEGERI PROGRAM STUDI KEAHLIAN TEKNIK BANGUNAN

    Directory of Open Access Journals (Sweden)

    Machmud Sugandi

    2012-08-01

    Full Text Available The pattern of funding vocational high school in the field of engineering building program in east java province. Funding of vocational education, especially in the fields of technology and industry study programs needed systematic planning funding based on learning activities in schools.Basically this study is ex-post facto, the approach used to solve the problems in this study is a quantitative approaches. The research question is how the structure of the pattern of vocational high school education funding based on the learning activities.The result of study is relationships between each cost components with of the source of funds to finance the international and a regulary vocational high school have the same funding pattern. Pola Pendanaan Penyelenggaraan Pendidikan Sekolah Menengah Kejuruan Negeri Program Studi Keahlian Teknik Bangunan. Pendanaan pendidikan kejuruan, khususnya di bidang studi teknologi dan industri diperlukan perencanaan pendanaan yang sistematis berdasarkan kegiatan pembelajaran di sekolah. Jenis penelitian ini adalah ex-post facto, pendekatan kuanti­ta­tif digunakan untuk memecahkan perma­salah­an penelitian. Masalah penelitian ada­lah bagaimanakah struktur pola pendanaan pendidikan sekolah menengah kejuruan yang didasarkan pada kegiatan pembelajaran. Hasil penelitian adalah pola hubungan antara setiap komponen biaya dengan sumber dana pendidikan sekolah menengah kejuruan bertaraf internasional dan reguler me­miliki pola pendanaan yang sama.

  17. PENGEMBANGAN SISTEM INFORMASI MANAJEMEN LABORATORIUM TEKNIK MEKANIK OTOMOTIF PADA SMK BERBASIS DATABASE MICROSOFT ACCESS

    Directory of Open Access Journals (Sweden)

    Taufik Didik Setiawan

    2012-08-01

    Full Text Available Activities in laboratory require regular and organized administration, so the laboratory can be arranged and functioned in an optimal manner. Administrative services system in Automotive Mechanical Engineering Laboratory at SMK consisted of the equipment loaning, supplying, inventory, and maintenance sector is still using an old system causing hindered activities in the laboratory. Developed MIS Labora­tory is a means to make use of the computer optimally at SMK. Therefore so, adminis­trative services system becomes faster and supports decision making processes. Kegiatan dalam laboratorium membutuhkan administrasi yang reguler dan terorganisasi sehingga laboratorium diatur dan difungsikan secara optimal. Sistem layanan administratif pada Laboratorium Teknik Mekanik Otomotif di SMK meliputi peminjaman peralatan, penyediaan alat dan bahan, inventori, dan layanan perawatan masih menggunakan sistem lama yang mengakibatkan hambatan pada aktivitas di laboratorium. Sistem manajemen informasi laboratorium yang dikembang­kan sebagai alat bantu layanan administrasi yang mengoptimalkan penggunaan komputer di SMK. Dengan demikian sistem layanan administrasi dapat berjalan lebih cepat dan men­dukung sistem pengambilan keputusan.

  18. Teknik Gelatinisasi Tepung Beras untuk Menurunkan Penyerapan Minyak Selama Penggorengan Minyak Terendam

    Directory of Open Access Journals (Sweden)

    Florentina Florentina

    2017-02-01

    Full Text Available Pregelatinized rice flour is one of ingredients that can reduce oil uptake. Gelatinization can be processed by drum drying, extrusion, and steaming. The aim of this research was to know the effect of gelatinization rice flour by drum drying, extrusion, and cooking rice on water holding capacity, degree of gelatinization, and oil uptake. Oil uptake was analyzed by using food model that substituted with 50 % pregelatinized flour. Results indicated that degree of gelatinization and water holding capacity of pregelatinized flour by drum drying was higher than extrusion and cooking rice. The highest reducing oil uptake of product was produced using pregelatinized flour by drum dryer was 33.70 % while by extruder which was 13.32 % and rice cooker was 10.09 % ABSTRAK Tepung beras pragelatinisasi merupakan salah satu ingredien yang dapat mengurangi penyerapan minyak. Proses gelatinisasi dapat dilakukan dengan metode pengeringan drum, ekstrusi, dan pengukusan. Penelitian ini bertujuan untuk mengetahui pengaruh teknik gelatinisasi tepung beras dengan pengeringan drum, ekstrusi, dan pemasakan nasi terhadap daya ikat air, derajat gelatinisasi dan penyerapan minyak. Penyerapan minyak dianalisis dengan menggunakan model pangan yang telah disubtitusi 50 % tepung pragelatinisasi. Hasil penelitian menunjukkan bahwa derajat gelatinisasi dan daya ikat air pada tepung pragelatinisasi dari pengeringan drum lebih tinggi daripada proses ekstrusi dan pemasakan nasi. Penurunan penyerapan minyak tertinggi dihasilkan pada produk dengan penggunaan tepung pragelatinisasi pengeringan drum yaitu 33,70 %, sedangkan ekstruder sebesar 13,32 % dan pemasak nasi sebesar 10,09 %.

  19. The Corrosion Protection of Magnesium Alloy AZ31B

    Science.gov (United States)

    Danford, M. D.; Mendrek, M. J.; Mitchell, M. L.; Torres, P. D.

    1997-01-01

    Corrosion rates for bare and coated Magnesium alloy AZ31B have been measured. Two coatings, Dow-23(Trademark) and Tagnite(Trademark), have been tested by electrochemical methods and their effectiveness determined. Electrochemical methods employed were the scanning reference electrode technique (SRET), the polarization resistance technique (PR) and the electrochemical impedance spectroscopy technique (EIS). In addition, general corrosion and stress corrosion methods were employed to examine the effectiveness of the above coatings in 90 percent humidity. Results from these studies are presented.

  20. Enhancing Microstructure and Mechanical Properties of AZ31-MWCNT Nanocomposites through Mechanical Alloying

    Directory of Open Access Journals (Sweden)

    J. Jayakumar

    2013-01-01

    Full Text Available Multiwall carbon nanotubes (MWCNTs reinforced Mg alloy AZ31 nanocomposites were fabricated by mechanical alloying and powder metallurgy technique. The reinforcement material MWCNTs were blended in three weight fractions (0.33%, 0.66%, and 1% with the matrix material AZ31 (Al-3%, zinc-1% rest Mg and blended through mechanical alloying using a high energy planetary ball mill. Specimens of monolithic AZ31 and AZ31-MWCNT composites were fabricated through powder metallurgy technique. The microstructure, density, hardness, porosity, ductility, and tensile properties of monolithic AZ31 and AZ31-MWCNT nano composites were characterized and compared. The characterization reveals significant reduction in CNT (carbon nanoTube agglomeration and enhancement in microstructure and mechanical properties due to mechanical alloying through ball milling.

  1. Reorganization of Damaged Chromatin by the Exchange of Histone Variant H2A.Z-2

    Energy Technology Data Exchange (ETDEWEB)

    Nishibuchi, Ikuno [Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima (Japan); Department of Radiation Oncology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan); Department of Radiation Oncology, Hiroshima Prefectural Hospital, Hiroshima (Japan); Suzuki, Hidekazu; Kinomura, Aiko; Sun, Jiying; Liu, Ning-Ang [Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima (Japan); Horikoshi, Yasunori [Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima (Japan); Research Center for Mathematics of Chromatin Live Dynamics, Hiroshima University, Hiroshima (Japan); Shima, Hiroki [Department of Biochemistry, Graduate School of Medical Sciences, Tohoku University, Sendai (Japan); Kusakabe, Masayuki; Harata, Masahiko [Laboratory of Molecular Biology, Graduate School of Agricultural Science, Tohoku University, Sendai (Japan); Fukagawa, Tatsuo [Department of Molecular Genetics, National Institute of Genetics and The Graduate University for Advanced Studies, Mishima (Japan); Ikura, Tsuyoshi [Laboratory of Chromatin Regulatory Network, Department of Mutagenesis, Radiation Biology Center, Kyoto University, Kyoto (Japan); Ishida, Takafumi [Department of Cardiovascular Medicine, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan); Nagata, Yasushi [Department of Radiation Oncology, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima (Japan); Tashiro, Satoshi, E-mail: ktashiro@hiroshima-u.ac.jp [Department of Cellular Biology, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima (Japan); Research Center for Mathematics of Chromatin Live Dynamics, Hiroshima University, Hiroshima (Japan)

    2014-07-15

    Purpose: The reorganization of damaged chromatin plays an important role in the regulation of the DNA damage response. A recent study revealed the presence of 2 vertebrate H2A.Z isoforms, H2A.Z-1 and H2A.Z-2. However, the roles of the vertebrate H2A.Z isoforms are still unclear. Thus, in this study we examined the roles of the vertebrate H2A.Z isoforms in chromatin reorganization after the induction of DNA double-strand breaks (DSBs). Methods and Materials: To examine the dynamics of H2A.Z isoforms at damaged sites, we constructed GM0637 cells stably expressing each of the green fluorescent protein (GFP)-labeled H2A.Z isoforms, and performed fluorescence recovery after photobleaching (FRAP) analysis and inverted FRAP analysis in combination with microirradiation. Immunofluorescence staining using an anti-RAD51 antibody was performed to study the kinetics of RAD51 foci formation after 2-Gy irradiation of wild-type (WT), H2A.Z-1- and H2A.Z-2-deficient DT40 cells. Colony-forming assays were also performed to compare the survival rates of WT, H2A.Z-1-, and H2A.Z-2-deficient DT40 cells with control, and H2A.Z-1- and H2A.Z-2-depleted U2OS cells after irradiation. Results: FRAP analysis revealed that H2A.Z-2 was incorporated into damaged chromatin just after the induction of DSBs, whereas H2A.Z-1 remained essentially unchanged. Inverted FRAP analysis showed that H2A.Z-2 was released from damaged chromatin. These findings indicated that H2A.Z-2 was exchanged at DSB sites immediately after the induction of DSBs. RAD51 focus formation after ionizing irradiation was disturbed in H2A.Z-2-deficient DT40 cells but not in H2A.Z-1-deficient cells. The survival rate of H2A.Z-2-deficient cells after irradiation was lower than those of WT and H2A.Z-1- DT40 cells. Similar to DT40 cells, H2A.Z-2-depleted U2OS cells were also radiation-sensitive compared to control and H2A.Z-1-depleted cells. Conclusions: We found that vertebrate H2A.Z-2 is involved in the regulation of the DNA

  2. Reorganization of Damaged Chromatin by the Exchange of Histone Variant H2A.Z-2

    International Nuclear Information System (INIS)

    Nishibuchi, Ikuno; Suzuki, Hidekazu; Kinomura, Aiko; Sun, Jiying; Liu, Ning-Ang; Horikoshi, Yasunori; Shima, Hiroki; Kusakabe, Masayuki; Harata, Masahiko; Fukagawa, Tatsuo; Ikura, Tsuyoshi; Ishida, Takafumi; Nagata, Yasushi; Tashiro, Satoshi

    2014-01-01

    Purpose: The reorganization of damaged chromatin plays an important role in the regulation of the DNA damage response. A recent study revealed the presence of 2 vertebrate H2A.Z isoforms, H2A.Z-1 and H2A.Z-2. However, the roles of the vertebrate H2A.Z isoforms are still unclear. Thus, in this study we examined the roles of the vertebrate H2A.Z isoforms in chromatin reorganization after the induction of DNA double-strand breaks (DSBs). Methods and Materials: To examine the dynamics of H2A.Z isoforms at damaged sites, we constructed GM0637 cells stably expressing each of the green fluorescent protein (GFP)-labeled H2A.Z isoforms, and performed fluorescence recovery after photobleaching (FRAP) analysis and inverted FRAP analysis in combination with microirradiation. Immunofluorescence staining using an anti-RAD51 antibody was performed to study the kinetics of RAD51 foci formation after 2-Gy irradiation of wild-type (WT), H2A.Z-1- and H2A.Z-2-deficient DT40 cells. Colony-forming assays were also performed to compare the survival rates of WT, H2A.Z-1-, and H2A.Z-2-deficient DT40 cells with control, and H2A.Z-1- and H2A.Z-2-depleted U2OS cells after irradiation. Results: FRAP analysis revealed that H2A.Z-2 was incorporated into damaged chromatin just after the induction of DSBs, whereas H2A.Z-1 remained essentially unchanged. Inverted FRAP analysis showed that H2A.Z-2 was released from damaged chromatin. These findings indicated that H2A.Z-2 was exchanged at DSB sites immediately after the induction of DSBs. RAD51 focus formation after ionizing irradiation was disturbed in H2A.Z-2-deficient DT40 cells but not in H2A.Z-1-deficient cells. The survival rate of H2A.Z-2-deficient cells after irradiation was lower than those of WT and H2A.Z-1- DT40 cells. Similar to DT40 cells, H2A.Z-2-depleted U2OS cells were also radiation-sensitive compared to control and H2A.Z-1-depleted cells. Conclusions: We found that vertebrate H2A.Z-2 is involved in the regulation of the DNA

  3. Tank 241-AZ-102 Privatization Push Mode Core Sampling and Analysis Plan

    International Nuclear Information System (INIS)

    TEMPLETON, A.M.

    1999-01-01

    This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for samples obtained from tank 241-AZ-102

  4. Tank 241-AZ-102 Privatization Push Mode Core Sampling and Analysis Plan

    International Nuclear Information System (INIS)

    RASMUSSEN, J.H.

    2000-01-01

    This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for samples obtained from tank 241-AZ-102

  5. 241-AZ Tank Farm Construction Extent of Condition Review for Tank Integrity

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, Travis J.; Boomer, Kayle D.; Gunter, Jason R.; Venetz, Theodore J.

    2013-07-30

    This report provides the results of an extent of condition construction history review for tanks 241-AZ-101 and 241-AZ-102. The construction history of the 241-AZ tank farm has been reviewed to identify issues similar to those experienced during tank AY-102 construction. Those issues and others impacting integrity are discussed based on information found in available construction records, using tank AY-102 as the comparison benchmark. In the 241-AZ tank farm, the second DST farm constructed, both refractory quality and tank and liner fabrication were improved.

  6. Microstructural Characteristics and Mechanical Properties of 2205/AZ31B Laminates Fabricated by Explosive Welding

    Directory of Open Access Journals (Sweden)

    Yan Li

    2017-04-01

    Full Text Available A bimetal composite of 2205 duplex stainless steel and AZ31B magnesium alloy was cladded successfully through the method of explosive welding. The microstructural characteristics and mechanical properties of 2205/AZ31B bimetal composite are discussed. The interface of 2205/AZ31B bimetallic composite was a less regular wavy morphology with locally melted pockets. Adiabatic shear bands occurred only in the AZ31B side near explosive welding interface. The microstructure observed with EBSD showed a strong refinement near the interface zones. Line scan confirmed that the interface had a short element diffusion zone which would contribute to the metallurgical bonding between 2205 duplex stainless steel and AZ31B magnesium alloy. The value of micro-hardness near the bonding interface of composite plate increased because of work hardening and grain refinement. The tensile shear strength of bonding interface of 2205/AZ31B composite was 105.63 MPa. Tensile strength of 2205/AZ31B composite material was higher than the base AZ31B. There were two abrupt drops in stress in the stress–strain curves of the 2205/AZ31B composite materials.

  7. MENINGKATKAN TECHNICAL SKILL SISWA SMK TEKNIK BANGUNAN MELALUI PELAKSANAAN PRAKTIK KERJA INDUSTRI

    Directory of Open Access Journals (Sweden)

    Blima Oktaviastuti

    2016-04-01

    . Mengingat pembangunan infrastruktur negara saat sekarang lebih diutamakan, kebutuhan pekerja konstruksi menjadi hal yang utama. Lulusan SMK teknik bangunan diharapkan memiliki technical skill agar dapat bersaing dengan tenaga asing memasuki era MEA seperti sekarang.

  8. RANCANG BANGUN SISTEM INFORMASI MANAJEMEN ASET BERBASIS WEB UNTUK OPTIMALISASI PENELUSURAN ASET DI TEKNIK INDUSTRI UNDIP

    Directory of Open Access Journals (Sweden)

    Galih Setyo Pambudi

    2017-01-01

    ABSTRACT   Program Studi Teknik Industri (PSTI is one of the departments in the Faculty of Engineering, University of Diponegoro. In 2015 PSTI has had a new building to support lesson activity. Along with it PSTI also get lectures supporting assets such as computers, desks, chairs and others. However, asset management in PSTI is currently not running well, PSTI has no special asset database to simplify the management and tracking of assets. PSTI asset manager at this time only use data collection using Excel to record the availability of its assets and it also had not updated. Many assets in PSTI do not have an inventory number that has been given by the Unit Layanan Pengadaan (ULP Faculty of Engineering. This condition make difficult for searching their asset. These problems often lead to asset managers in the PSTI is difficult to determine the condition of the assets is good, broken or missing. This makes the process of replacing damaged assets PSTI in ULP be no maximum. Therefore, needed an information system that can run the asset management business into a neat and structured asset management department can be easy to perform management and asset tracking. The process of designing Asset Management Information System (SIMA begins with the identification of an asset management system that is currently running in PSTI and make the proposed new system. Furthermore, of the proposed system is designed DFD (Data Flow Diagram and ERD (Entity Relationship Diagram and also the information system interface design. From the design stage and then produced a web-based information system to manage assets in PSTI. Further verification and validation to determine the suitability of the design of the system with the end result of SIMA have been made. Last is comparing the old system with a new system to determine the differences that looks after the implementation of the new system.

  9. PENGEMBANGAN MEDIA AJAR LINE FOLLOWER ANALOG PADA MATA PELAJARAN PEREKAYASAAN SISTEM ROBOTIK KELAS XII TEKNIK ELEKTRONIKA INDUSTRI

    Directory of Open Access Journals (Sweden)

    Suwasono Suwasono

    2017-01-01

    Full Text Available This research aims at developing line follower analog media for robotic system engineering in SMKN 2 Singosari. The development was refered to modified model suggested by Sugiyono. The results of this development are in the form of modul, jobsheet, and trainer for robotic system engineering. The product was validated by content expertise I from Electrical Engineering Lecturer and obtained 92,06% of validity result. While the valifity result given the content expertise II from Robotic System Engineering teacher obtained 92,77%. In terms of media validity, the product obtained 94,81% from Electrical Engineering Lecturer and 94,02% from Robotic System Engineering Teacher. The product was also tested in XII Graders of Industry Electronics Engineering in SMKN 2 Singosari and obtained 88,20%. Thus, the media developed in the form of modul, jobsheet, and trainer of Robotic System Engineering within this study is considered as appropriate for XII Graders of Industry Electronics Engineering in SMKN 2 Singosari. Penelitian ini bertujuan untuk mengembangkan media ajar line follower analog pada mata pelajaran perekayasaan sistem robotik di SMKN 2 Singosari. Penelitian pengembangan mengacu pada model pengembangan Sugiyono yang dimodifikasi. Hasil pengembangan media ajar line follower analog berupa modul, jobsheet dan trainer untuk mata pelajaran Perekayasaan Sistem Robotik. Produk divalidasi ahli materi I dosen dari Jurusan Teknik Elektro memperoleh persentase sebesar 92,06%, ahli materi II dari guru mata pelajaran Perekayasaan Sistem Robotik memperoleh persentase sebesar 92,77%. Validasi media I dosen dari Jurusan Teknik Elektro memperoleh hasil persentase sebesar 94,81%, ahli media II dari guru mata pelajaran Perekayasaan Sistem Robotik memperoleh persentase sebesar 94,02%. Produk juga diujicobakan pada siswa kelas XII Teknik Elektronika Industri SMKN 2 Singosari diperoleh persentase sebesar 88,20% dan termasuk dalam kategori sangat layak. Sehingga produk

  10. 76 FR 62144 - Environmental Impact Statement for Implementation of Passenger Rail Service Between Tucson, AZ...

    Science.gov (United States)

    2011-10-06

    ... impacts to the natural and built environment of those alternatives, and invite public participation in the... will provide programmatic assessment of environmental effects associated with the construction... Environmental Impact Statement for Implementation of Passenger Rail Service Between Tucson, AZ and Phoenix, AZ...

  11. 76 FR 30299 - Proposed Establishment of Class E Airspace; Kayenta, AZ

    Science.gov (United States)

    2011-05-25

    ...-0393; Airspace Docket No. 11-AWP-2] Proposed Establishment of Class E Airspace; Kayenta, AZ AGENCY... action proposes to establish Class E Airspace at Kayenta Airport, Kayenta, AZ. Controlled airspace is...) standard instrument approach procedures at Kayenta Airport. The FAA is proposing this action to enhance the...

  12. 76 FR 3570 - Proposed Amendment of Class E Airspace; Taylor, AZ

    Science.gov (United States)

    2011-01-20

    ...-1189; Airspace Docket No. 10-AWP-19] Proposed Amendment of Class E Airspace; Taylor, AZ AGENCY: Federal... proposes to modify Class E airspace at Taylor Airport, Taylor, AZ. Controlled airspace is necessary to accommodate aircraft using the CAMBO One Departure Area Navigation (RNAV) out of Taylor Airport. The FAA is...

  13. Influence of the Composition of the Hank’s Balanced Salt Solution on the Corrosion Behavior of AZ31 and AZ61 Magnesium Alloys

    Czech Academy of Sciences Publication Activity Database

    Tkacz, J.; Slouková, K.; Minda, J.; Drábiková, J.; Fintová, Stanislava; Doležal, P.; Wasserbauer, J.

    2017-01-01

    Roč. 7, č. 11 (2017), č. článku 465. ISSN 2075-4701 Institutional support: RVO:68081723 Keywords : magnesium alloy * AZ31 * AZ61 * HBSS * HBSS+ * EIS * potentiodynamic test Subject RIV: JK - Corrosion ; Surface Treatment of Materials OBOR OECD: Coating and films Impact factor: 1.984, year: 2016 http://www.mdpi.com/2075-4701/7/11/465

  14. Internet video - teknik og pædagogik mødes på nettet

    Directory of Open Access Journals (Sweden)

    Dorte Sidelmann Jørgensen

    2004-05-01

    Full Text Available

    Første gang publiceret i UNEV nr. 3: Internet Video: Teknik og pædagogik mødes på nettet, april - juni 2004, red. Jens Dørup. ISSN 1603-5518.

    I nærværende UNEV tema som omhandler universiteternes brug af digital video tegnes en status over dette nye medies anvendelse rundt om i landet. En række af de flittigste brugere, som også har været iblandt de første på området, fortæller om deres praktiske erfaringer, som naturligt nok har været af både teknologisk og pædagogisk art. Som universitetsundervisere og forskere er vi vandt til et relativt lavt budget, og vi har måttet klare mange teknologiske opgaver uden professionel hjælp. Til gengæld stimulerer denne situation underviseren til at inddrage pædagogiske og teknologiske aspekter samtidigt, når videomediet og det nye potentialer skal afprøves og implementeres. Som læringsmedie adskiller Internet video sig på mange måder fra TV og analoge videobånd. De indlysende forskelle – om mulighederne for uafhængighed af tid og sted – kan snart erkendes og beskrives, men erfaringerne tyder på at disse forskelle, når det gælder om at stimulere læringen, måske er mindre betydningsfulde end mulighederne for at indarbejde, forankre og samvirke netbaseret video med øvrige læringsaktiviteter. Det aktuelle tema viser at de tekniske muligheder er tilgængelige og at vi mange steder er kommet godt i gang, men også at der er langt igen før danske universiteter til fulde har lært at udnytte potentialerne i digital video.

  15. MANAJEMEN KUALITAS MEDIA PENDEDERAN LELE PADA LAHAN TERBATAS DENGAN TEKNIK BIOFLOK

    Directory of Open Access Journals (Sweden)

    MN Abulias

    2014-11-01

    Full Text Available Akuakultur intensif bisa menyebabkan menurunnya kandungan oksigen dan meningkatnya kandungan limbah pada ekosistem perairan, khususnya nitrogen organik. Transfer teknologi sudah dilakukan dengan tujuan untuk mengelola kegiatan budidaya lele pada daerah terbatas menggunakan bioflok. Tujuan penelitian ini adalah membandingkan pertumbuhan ikan lele yang dipelihara menggunakan sistem bioflok dan non bioflok. Sampel penelitian yang digunakan adalah 500 bibit ikan berumur 10 hari, yang dipelihara selama 30 hari. Pengamatan dilakukan pada hari ke-0, 15, dan 30. Parameter pertumbuhan yang diamati adalah panjang dan berat ikan. Parameter lingkungan yang diamati adalah suhu air dan udara, karbondioksida terlarut, oksigen terlarut, dan pH. Hasil penelitian menunjukkan bahwa ada perbedaan peningkatan panjang dan berat tubuh benih lele pada kedua media budidaya. Meskipun peningkatan pertumbuhan tidak terlalu tinggi, namun cukup memberikan gambaran bahwa benih lele yang dipelihara dengan aplikasi bioflok mengalami pertumbuhan yang lebih baik. Hal ini mengindikasikan bahwa pakan yang diberikan dan media pemeliharaannya mampu mendukung pertumbuhan benih lele. Media pemeliharaan yang mengaplikasikan teknik bioflok menunjukkan kondisi yang lebih baik dan relatif ideal untuk pendederan lele. Hal ini juga diperkuat dengan relatif rendahnya tingkat kematian benih selama pemeliharaan, yaitu  10%. Intensive aquaculture might decrease of the dissolved oxygen and increase the wastes, particularly organic nitrogen, in the aquatic ecosystem. Technology transfer has long been made to improve the catfish rearing management in confined tanks using biofloc. The objective of the research was to compare the growth of catfish reared in non-biofloc and biofloc systems. Samples were 500 catfish seedlings aged 10 days and reared for 30 days. Observations were made on day 0, 15, and 30. Growth parameters observed were length and weight of the fish. The environmental parameters

  16. Meningkatkan Kemampuan Menyimak Siswa Kelas I Melalui Teknik Permainan Pesan Berantai Pada Pembalajaran Bahasa Indonesia

    Directory of Open Access Journals (Sweden)

    Imam Imam

    2014-08-01

    Full Text Available Kondisi riil pendidikan yang ada di daerah, masih banyak menemukan guru berada dalam situasi yang kurang menguntungkan untuk melaksanakan tugas dengan professional.Banyak guru yang ditempatkan di dalam ruang yang penuh sesak dengan anak didik dengan perlengkapan yang kurang memadai, para guru diharapkan mampu melaksanakan tugas mulia untuk mendidik generasi penerus anak bangsa.Hal demikian sebagaimana dialami pula oleh peneliti selaku guru di SDN Pinggir Papas 1, dimana SDN Pinggir Papas 1 juga terletak di daerah pinggiran dengan penduduk yang kurang berpendidikan.Siswa kelas 1A sebagian besar tidak mempunyai latar pendidikan dari TK, mereka memulai segalanya (mengenal huruf dan angka dari kelas 1.Kemampuan berbahasa Indonesia siswa kelas 1A juga sangat kurang, mereka terbiasa menggunakan bahasa Madura sebagai bahasa komunikasi sehari-hari. Untuk itu peneliti selaku guru kelas 1A, merasa kesulitan di dalam membelajarkan bahasa Indonesia kepada siswa. Hal ini terlihat dari hasil belajar siswa yang rendah di segala aspek keterampilan bahasa, yaitu pada aspek membaca, menulis, menyimak, dan berbicara. Setiap diadakan penilaian terhadap salah satu aspek keterampilan bahasa yang diajarkan, misalnya keterampilan menyimak, nilai hasil belajar siswa selalu di bawah KKM yang telah ditentukan yaitu 65, hanya ada beberapa siswa yang mampu memperoleh nilai di atas KKM yang telah ditentukan.Sebagai alternatif pemecahan masalah maka peneliti sebagai guru kelas 1 berupaya melakukan perbaikan pembelajaran melalui penelitian tindakan kelas yang berjudul “Meningkatkan Kemampuan Menyimak Siswa Kelas 1A Melalui Teknik Permainan Pesan Berantai pada Pembelajaran Bahasa Indonesia”.Berdasarkan hasil penelitian tindakan kelas yang dilakukan selama 2 siklus dengan menggunakan metode observasi dan tes serta data catatan lapangan selama proses pembelajaran, dapat disimpulkan bahwa kemampuan menyimak siswa kelas 1A dapat ditingkatkan melalui penerapan metode permainan

  17. KOMPONEN WEB DATA ANALYZER PADA IE STUDI KASUS: AKSES WEB TERFAVORIT LABORATORIUM IBS TEKNIK INFORMATIKA - ITS

    Directory of Open Access Journals (Sweden)

    Darlis Heru Murti

    2005-07-01

    Explorer. Untuk itu di dalam pelaksanaan penelitian ini, akan dilakukan perancangan dan pembuatan sebuah perangkat lunak komponen Web Data Analyzer yang melekat pada browser Internet Explorer untuk pencarian akses web terfavorit pengguna. Uji coba dan evaluasi pada penelitian ini dilakukan dengan melakukan instalasi komponen Web Data Analyzer pada sejumlah workstation di Laboratorium IBS Teknik Informatika ITS. Hasil uji coba menunjukkan bahwa komponen Web Data Analyzer mampu memonitor dan menganalisa data aktivitas browsing pengguna serta melakukan otomatisasi terhadap fitur Favorites Internet Explorer dari data aktivitas browsing pengguna yang berhasil tersimpan ke database server. Kata kunci: band object, explorer bar, browser helper object (bho, http analyzer.

  18. Perancangan Implementasi E-Learning Berbasis Moodle Dalam Matakuliah Statistika Program Studi Pendidikan Teknik Informatika Dan Komputer

    Directory of Open Access Journals (Sweden)

    Affni Syaviera Nova

    2017-06-01

    Full Text Available Penelitian dilakukan dengan tujuan merancang implementasi e-learning berbasis Moodle berupa website dalam matakuliah Statistika program studi Pendidikan Teknik Informatika dan Komputer. Sistem e-learning ini dirancang untuk diimpelementasikan pada semua matakuliah yang ada pada program studi Pendidikan Teknik Informatika dan Komputer, sehingga membantu kegiatan perkuliahan. Sebagai pengembangan awal, sistem e- learning ini diuji coba pada matakuliah statistika. Penelitian ini menggunakan desain penelitian dan pengembangan (Research and Development menurut Sugiyono (2010. Subyek penelitian yaitu dosen statistika dan mahasiswa yang telah mengikuti perkuliahan Statistika ditentukan secara purposive sampling. Data yang diambil adalah kelayakan dari segi materi dan media melalui angket, dan tanggapan mahasiswa melalui angket. Tanggapan ahli menunjukkan e-learning berbasis Moodle sangat baaik dari segi media dan bagus dari segi materi. Hasil angket tanggapan siswa pada uji coba skala kecil menunjukkan bahwa mayoritas siswa memberikan tanggapan positif terhadap kegiatan pembelajaran menggunakan media e-learning berbasis Moodle. Produk final e-learning berbasis Moodle berisi modul, video, ppt, chat, kelas virtual dan forum diskusi. Berbagai konten dan fasilitas yang dimiliki e-learning yang dikembangkan membuat pembelajaran Sistem Gerak menjadi lebih menarik. Berdasarkan hasil analisis dan pembahasan dapat disimpulkan bahwa e-learning berbasis Moodle sesuai dan layak diterapkan pada matakuliah Statistika.

  19. Sistem Administrasi Proses Belajar Mengajar Di Program Studi Teknik Telekomunikasi PNJ Berbasis Android dengan Transmisi WiFi

    Directory of Open Access Journals (Sweden)

    Toto Supriyanto

    2016-11-01

    Full Text Available Sistem Administrasi Proses Belajar Mengajar di Program Studi Teknik Telekomunikasi PNJ Berbasis Android dengan Transmisi Wifi  merupakan sebuah sistem untuk pencatatan kegiatan belajar mengajar berupa absen mahasiswa dan materi pembelajaran setiap harinya. Web server bertindak sebagai admin dan aplikasi android sebagai user. User dalam hal ini adalah dosen. Aplikasi ini terinstal pada tablet PC dan setiap menggunakan aplikasi ini user akan melakukan login terlebih dahulu dengan memasukkan username dan password sesuai dengan database server. Setelah melakukan login aplikasi akan menampilkan halaman menu. Pada halaman menu berisi  profil dosen, kelas dan mata kuliah yang diajar oleh dosen, kurikulum yang ada di program studi teknik telekomunikasi PNJ dan jadwal mengajar dosen. Pada menu jadwal, dosen dapat melakukan absensi mahasiswa didik. Dosen melakukan absen satu persatu dengan menekan tombol “absen”. Data absensi dikirimkan ke web server dengan transmisi wifi dan masuk ke halaman lembar kontrol kegiatan dimana user diminta untuk mencatatkan judul materi. Web server akan menyimpan seluruh data yang dikirimkan oleh aplikasi android dan mengakumulasi absensi mahasiswa. Jika terdapat mahasiswa yang tidak hadir pada jam belajar dan memiliki masalah pada jumlah absensi sistem akan mengirimkan notifikasi berupa SMS kepada mahasiswa bersangkutan melalui SMS gateway.

  20. Development of AZS refractories for the glass industry

    International Nuclear Information System (INIS)

    Guzman, A.M.; Rodriguez, P.

    2004-01-01

    Refractory materials can support high temperatures, thermal strength and the contact with aggressive environments, for this reason they are widely used in the cement, glass and steel industry. Commercial AZS (alumina-zirconia-silica) refractories are a good alternative in refractory materials for the glass industry' because they can support the aggressive conditions during liquid processing of glass. However, another problem encountered in glass industry is contamination by refractory' material that fall into the molten glass, which can produce a series of defects in the final product. This research was conducted to develop new formulations of AZS refractories with different amounts of ZrO 2 with the purpose of improving the characteristics, properties and the work conditions in the glass melting furnaces and, at the same time, lower the costs this type of refractories. The results obtained indicate that the composition with low content of ZrO 2 can provide better properties than the commercial product, with some modifications in the particle size distribution. Copyright (2004) AD-TECH - International Foundation for the Advancement of Technology Ltd

  1. Influence of the Composition of the Hank’s Balanced Salt Solution on the Corrosion Behavior of AZ31 and AZ61 Magnesium Alloys

    Directory of Open Access Journals (Sweden)

    Jakub Tkacz

    2017-11-01

    Full Text Available The electrochemical corrosion characteristics of AZ31 and AZ61 magnesium alloys were analyzed in terms of potentiodynamic tests and electrochemical impedance spectroscopy. The influence of the solution composition and material surface finish was examined also through the analysis of corrosion products created on the samples’ surface after electrochemical measurements in terms of scanning electron microscopy using energy-dispersive spectroscopy. Obtained data revealed the differences in the response of the magnesium alloys to enriched Hank’s Balanced Salt Solution—HBSS+ (with Mg2+ and Ca2+ ions and Hank’s Balanced Salt Solution—HBSS (without Mg2+ and Ca2+ ions. Both examined alloys exhibited better corrosion resistance from the thermodynamic and kinetic point of view in the enriched HBSS+. AZ61 magnesium alloy reached higher values of polarization resistance than AZ31 magnesium alloy in both the used corrosion solutions. Phosphate-based corrosion products were characteristic for the AZ31 and AZ61 alloys tested in the HBSS (without Mg2+ and Ca2+ ions. The combination of phosphate-based corrosion products and clusters of MgO and Mg(OH2 was typical for the surface of samples tested in the enriched HBSS+ (with Mg2+ and Ca2+ ions. Pitting corrosion attack was observed only in the case of enriched HBSS+.

  2. In Vitro Studies on the Degradability, Bioactivity, and Cell Differentiation of PRP/AZ31B Mg Alloys Composite Scaffold

    Directory of Open Access Journals (Sweden)

    Jian Zou

    2017-01-01

    Full Text Available In recent years, more and more methods have been developed to improve the bioactivity of the biodegradable materials in bone tissue regeneration. In present study, we used rat mesenchymal stem cells (rMSCs to evaluate the outcomes of Mg alloys (AZ31B, Magnesium, and Aluminum and Platelet-rich plasma (PRP/Mg alloys on rMSCs biocompatibility and osteogenic differentiation. Water absorption experiments indicated that both bare AZ31B and PRP/AZ31B were capable of absorbing large amounts of water. But the water absorption ratio for PRP/AZ31B was significantly higher than that for bare AZ31B. The degradability experiments implied that both samples degraded at same speed. rMSCs on the surface of AZ31B distributed more and better than those on the AZ31B scaffold. In ALP activity experiment, the activity of rMSCs on the PRP/AZ31B was markedly higher than that on the AZ31B scaffolds on the 7th day and 14th day. qRT-PCR also showed that OPN and OCN were expressed in both samples. OPN and OCN expression in PRP/AZ31B sample were higher than those in bare AZ31B samples. In summary, the in vitro study implied that AZ31B combined with PRP could remarkably improve cell seeding, attachment, proliferation, and differentiation.

  3. An Analysis of Magnesium Alloy AZ31B-H24 for Ballistic Applications

    Science.gov (United States)

    2007-12-01

    CELIUS MATERIAL TEKNIK KARLSKOGA AB L HELLNER S 69180 KARLSKOGA SWEDEN 3 CENTRE D’ETUDES GRAMAT J CAGNOUX C GALLIC J TRANCHET... GRAMAT 46500 FRANCE 1 MINISTRY OF DEFENCE DGA DSP STTC G BRAULT 4 RUE DE LA PORTE D’ISSY 00460 ARMEES F 75015 PARIS FRANCE 1

  4. Dictionary of engines. The internal combustion engine from A-Z; Lexikon Motorentechnik. Der Verbrennungsmotor von A-Z

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, F. (ed.); Basshuysen, R. van

    2004-04-01

    This dictionary describes current engine technology and gives an outlook to the future. Cross-references, broader and narrower terms ensure optimal user guidance. Entries do not stand alone but provide content-oriented information. About 4,500 terms are included from A-Z, providing an outline of subjects like exhaust systems, acoustics, supercharging, combustion chamber, injection systems, control, flame propagation, mixing, catalytic converters, pistons, fuels, cooling, crank casing, stratified charging, lambda control, camshaft, oil, particulate filters, sensors/actuators, pollutants, valves, combustion processes, efficiency, ignition, cylinder head. The dictionary is for development engineers in the motor car industry, in component and system development in the supply industry, university teachers and students, foremen in motor car repair shops, etc. (orig.) [German] Das Lexikon Motorentechnik ist ein Nachschlagewerk, das die aktuelle Motorentechnik umfassend beschreibt und Ausblicke in der Zukunft ermoeglicht. Das ausgefeilte System aus Querverweisen fuehrt alle Unterbegriffe zum Hauptbegriff und ermoeglicht so eine optimale Benutzerfuehrung. Dadurch stehen die Stichwoerter nicht isoliert, sondern es werden inhaltlich zusammenhaengende Betrachtungen moeglich. Der Inhalt umfasst 4 500 Begriffe von A-Z wie z.B.: Abgastechnik, Akustik, Aufladung, Brennraum, Einspritzsysteme, Elektronische Motorsteuerung, Flammenausbreitung, Gemischbildung, Katalysator, Kolben, Kraftstoff, Kuehlung, Kurbelgehaeuse, Kurbeltrieb, Ladungswechsel, Lambda-Regelung, Nockenwelle, Oel, Partikelfilter, Sensoren/Aktuatoren, Schadstoffe, Ventiltrieb, Verbrennungsverfahren, Wirkungsgrad, Zuendung, Zylinderkopf. Die Zielgruppen waeren Ingenieure in Motoren- und Fahrzeugentwicklung der Automobilindustrie, Ingenieure in der Komponenten- und Systementwicklung der Zuliefererindustrie, Professoren und Studenten an Hochschulen mit Schwerpunkt Kraftfahrzeugtechnik, Meister in Kfz-Werkstaetten. (orig.)

  5. Identifikasi Transgene pada Tanaman Padi (oryza sativa var. koshihikari yang Ditransformasi dengan Bantuan Agrobacterium tumefaciens, Menggunakan Metode Tanpa Teknik Kultur Jaringan.

    Directory of Open Access Journals (Sweden)

    I Putu Suparthana

    2015-04-01

    Full Text Available Metode transformasi tanaman dengan bantuan Agrobacterium tumefaciens biasa dilakukan dengan melibatkan teknik kultur jaringan, akan tetapi teknik kultur jaringan memiliki beberapa kelemahan yaitu memerlukan suatu kondisi steril, memakan banyak waktu, sering terjadi mutasi dalam proses kultur in vitro dan sejumlah tanaman bersifat rekalsitran pada tahap regenerasi. Disisi lain metode baru (in planta transformation system yang dikembangkan dalam penelitian ini mampu mengatasi kelemahan-kelemahan tersebut. Penelitian dilakukan pada tanaman padi dengan bantuan A. tumefaciens sebagai inokulum namun tidak melibatkan teknik kultur jaringan pada masa regenerasinya. Biji padi (Oryza sativa L. var. Koshihikari direndam dalam air selama 2 hari, dengan demikian embrionya yang mengandung sel apikal meristem dapat diinokulasi dengan cara menusukkan jarum yang telah dicelupkan dalam inokulum. Biji padi yang telah diinokulasi selanjutnya ditumbuhkan dilapangan selayaknya pembenihan biasa tanpa perlakuan steril. Untuk menentukan keberhasilan teknik ini, dua jenis strain mutan A. tumefaciens (M-21 dan LBA4404 digunakan dalam transformasi. Mutan M-21 mengandung Tn5 tersisip dalam gen iaaM dan mutan LBA4404 membawa binari plasmid vektor. Transgen dari mutan M-21 dapat diidentifikasi dari perubahan fenotipe pada tanaman padi transgenik sedangkan dari mutan LBA4404 dapat diidentifikasi dengan uji histokimia dan ketahanan terhadap antibitik (hygromycin B.Kata kunci: in planta transformation, A. tumefaciens, transformation method

  6. Klasifikasi Dokumen Karya Akhir Mahasiswa Menggunakan Naïve Bayes Classifier (NBC Berdasarkan Abstrak Karya Akhir Di Jurusan Teknik Elektro Universitas Negeri Jakarta

    Directory of Open Access Journals (Sweden)

    Nur Indah Pratiwi

    2017-06-01

    Full Text Available Dokumen karya akhir di Jurusan Teknik Elektro Universitas Negeri Jakarta setiap tahunnya bertambah, pengklasifikasian dokumen menjadi hal yang sangat penting untuk mengorganisasikan dokumen sehingga dapat memudahkan pencarian. Pengembangan Sistem klasifikasi dokumen bertujuan untuk mengembangkan sebuah sistem yang dapat mengklasifikasikan dokumen karya akhir mahasiswa berdasarkan abstrak karya akhir menggunakan algoritma Naïve Bayes Classifier (NBC. Sehingga, dapat memudahkan pengklasifikasian dokumen karya akhir di Jurusan Teknik Elektro. Dalam penelitian ini menggunakan metode eksperimen dan menggunakan 100 dokumen abstrak, 90 dokumen sebagai data train dan 10 dokumen sebagai data test. Data diambil dari skripsi mahasiswa Jurusan Teknik Elektro Universitas Negeri Jakarta dari 14 Maret 2014 sampai dengan 27 Maret 2014. Setelah melakukan proses pengembangan perangkat lunak, dihasilkan sebuah sistem klasifikasi yang bernama Sistem Klasifikasi Dokumen Skripsi. Sistem di implementasi menggunakan PHP dan MySQL, dan diuji menggunakan K-Fold Cross Validation (10 Fold. Berdasarkan pada hasil uji Sistem didapatkan hasil tingkat akurasi sebesar 81%. Oleh karena itu, dapat disimpulkan bahwa Sistem Klasifikasi Dokumen Abstrak Karya Akhir Menggunakan Algoritma Naïve Bayes di Jurusan Teknik Elektro telah berhasil dikembangkan.

  7. 241-AY/AZ waste storage tanks: Supplemental gravity load analysis. Volume 1

    International Nuclear Information System (INIS)

    Baliga, R.

    1994-01-01

    An analysis of the 241SY tanks performed by ADVENT(1994b) to resolve dome overload issues indicated that the tank can sustain the dome loads resulting from additional soil overburden depth, increased soil density, and increased concentrated load. Similar issues exist for the 241AY/AZ tanks and therefore, an interim analysis of the 241AY/AZ tanks is presented herein. The scope of this effort is to review and compare all design drawings pertaining to the 241AY and 241AZ tanks with those pertaining to the 241SY tanks; to modify the axisymmetric model of the 241SY tanks to represent the 241AY/AZ tanks; and to evaluate the effect of additional dome load on the 241AY/AZ tanks by performing a structural analysis for gravity loads (dead load + live load). ADVENTS's additional scope of work is to perform a qualitative evaluation of the 241AY/AZ tanks for seismic and thermal loadings (Vollert 1982 and Blume 1971). This qualitative evaluation does not include any detailed finite element analysis of the tanks. The following design-based gravity loading conditions are used in this interim analysis of the 241AY/AZ tanks to determine a baseline for the tank stresses or section loads

  8. Histone H2A.Z is essential for estrogen receptor signaling

    Science.gov (United States)

    Gévry, Nicolas; Hardy, Sara; Jacques, Pierre-Étienne; Laflamme, Liette; Svotelis, Amy; Robert, François; Gaudreau, Luc

    2009-01-01

    Incorporation of H2A.Z into the chromatin of inactive promoters has been shown to poise genes for their expression. Here we provide strong evidence that H2A.Z is incorporated into the promoter regions of estrogen receptor (ERα) target genes only upon gene induction, and that, in a cyclic pattern. Moreover, members of the human H2A.Z-depositing complex, p400, also follow the same gene recruitment kinetics as H2A.Z. Importantly, cellular depletion of H2A.Z or p400 leads to a severe defect in estrogen signaling, including loss of estrogen-specific cell proliferation. We find that incorporation of H2A.Z within TFF1 promoter chromatin allows nucleosomes to adopt preferential positions along the DNA translational axis. Finally, we provide evidence that H2A.Z is essential to allow estrogen-responsive enhancer function. Taken together, our results provide strong mechanistic insight into how H2A.Z regulates ERα-mediated gene expression and provide a novel link between H2A.Z–p400 and ERα-dependent gene regulation and enhancer function. PMID:19515975

  9. About some corrosion mechanisms of AZ91D magnesium alloy

    International Nuclear Information System (INIS)

    Ballerini, Gaia; Bardi, Ugo; Bignucolo, Roberto; Ceraolo, Giuseppe

    2005-01-01

    The present work is dedicated to a study of the corrosion resistance of AZ91D (91% Mg) alloy in wet environments. Three industrial alloys obtained by die-casting or sand casting were subjected to salt spray corrosion tests (ASTM-B117 standard) and immersion tests. Weight loss kinetic curves were measured. Surface analysis was performed by X-ray photoelectron diffraction (XPS). After corrosion the sand cast alloy presents a surface mainly enriched in hydroxides and carbonates while the die-cast alloy presents a surface enriched also in mixed Mg-Al oxides. The quantitative analysis of the rate Mg/Al shows an enrichment in aluminium for the die-cast alloys in comparison to the sand cast alloy

  10. High speed cutting of AZ31 magnesium alloy

    Directory of Open Access Journals (Sweden)

    Liwei Lu

    2016-06-01

    Full Text Available Using LBR-370 numerical control lathe, high speed cutting was applied to AZ31 magnesium alloy. The influence of cutting parameters on microstructure, surface roughness and machining hardening were investigated by using the methods of single factor and orthogonal experiment. The results show that the cutting parameters have an important effect on microstructure, surface roughness and machine hardening. The depth of stress layer, roughness and hardening present a declining tendency with the increase of the cutting speed and also increase with the augment of the cutting depth and feed rate. Moreover, we established a prediction model of the roughness, which has an important guidance on actual machining process of magnesium alloy.

  11. commodity: el caso del mercado internacional del azúcar

    Directory of Open Access Journals (Sweden)

    Julio César Alonso

    2013-01-01

    Full Text Available Este trabajo estudia el comportamiento estacional de los precios internacionales del azúcar transados en Nueva York y Londres. Para este caso, empleando pruebas de raíces estacionales y una muestra mensual desde enero de 1989 hasta diciembre de 2010, se encuentra la existencia de un comportamiento estacional estocástico no estacionario. Dicha conducta implica que un “verano” se puede convertir en un “invierno”, resultado que no había sido documentado previamente en estos mercados. Por otro lado, empleando dicho hallazgo, los resultados muestran que es posible construir un modelo autorregresivo de media móvil que se comporta relativamente mejor al pronosticar el precio frente a un modelo que no tiene en cuenta dicho tipo de estacionalidad.

  12. TEKNIK JARINGAN SYARAF TIRUAN FEEDFORWARD UNTUK PREDIKSI HARGA SAHAM PADA PASAR MODAL INDONESIA

    Directory of Open Access Journals (Sweden)

    Budi Bambang DP.

    1999-01-01

    , beberapa model analisa teknik telah dipakai dan dikembangkan, beberapa analisa tersebut seperti : MACD , Fourier Transform, Accumulator Swing Index, Stochastic Oscilator dan lain lain. Sebagai masukannya digunakan beberapa macam kombinasi harga seperti : harga pembukaan, tertinggi, terendah, penutupan kemarin dan penutupan hari ini serta volume perdagangan. Dan sebagai keluaran adalah suatu grafik yang menampilkan suatu keputusan beli atau jual. Suatu cara lain dalam menentukan harga saham adalah dengan menggunakan metoda 'Fundamental Analysis', yaitu suatu analisa dimana penampilan dari suatu kinerja perusahaan didasarkan atas ratio-ratio / laporan keuangan yang ada. Teknologi sistem jaringan syaraf tiruan telah di-implementasikan dalam berbagai aplikasi terutama dalam hal pengenalan pola. Kemampuan inilah yang telah menarik beberapa kalangan dalam menggunakan jaringan syaraf tiruan untuk keperluan kesehatan, keuangan , investasi, marketing dan lain lain. Pada makalah ini akan dibahas penggunaan Jaringan syaraf tiruan Feedforward/Backpropagarion. Data dari harga saham dapat diperlakukan secara 'time series' . Jika kita mempunyai data harian selama perioda tertentu, misal : Xt (t=1,2,......, maka harga saham pada perioda berikutnya (t+h dapat diprediksi (waktu yang digunakan bisa jam, harian, mingguan , bulanan ataupun tahunan . Demikian seterusnya dilakukan suatu iterasi berulang hingan N hari kerja. Untuk mendapatkan hasil prediksi yang baik maka pada jaringan syaraf buatan hasus di-umpankan suatu masukan yang mewakili dari beberapa aspek atau segi penunjang harga suatu saham. Kemudian dilakukan prinsip pembobotan yang diadaptasikan untuk meminimumkan kesalahan prediksi pada satu langkah kedepan. Dengan menggunakan bobot akhir dilakukan suatu tindakan untuk meminimumkan kesalahan total untuk iterasi berikutnya. Saham yang akan dibahas adalah saham Semen Gresik (SMGR dan Gudang Garam (GGRM Kata kunci: prediksi harga saham, jaringan syaraf tiruan, time series feedforward

  13. MODEL PEMBELAJARAN PRAKTIK PENGELASAN SHIELED METAL ARC WELDING(SMAW POSISI 1G JURUSAN TEKNIK PENGELASAN

    Directory of Open Access Journals (Sweden)

    Masri Bin Ardin

    2016-08-01

    Full Text Available Penelitian ini bertujuan untuk: (1 mendeskripsikan model pembelajaran praktik yang berlangsung atau disebut model pembelajaran regular praktek pengelasan SMAW posisi 1G di SMK Negeri 2 Pengasih; (2 mengetahui efektifitas dan mendeskripsikan bahan yang digunakan dalam praktek pengelasan SMAW posisi 1G, misalnya: besi plat, mata gerinda, elektroda, dan waktu yang digunakan selama praktek pengelasan SMAW posisi 1G. Penelitian ini merupakan penelitian deskriptif dengan teknik pengumpulan data menggunakan wawancara, dokumentasi, angket dan penilaian skill pengelasan. Asessment skill pengelasan mengacu pada Acean Skill Welding Competition. Hasil penelitian yaitu: (1 model pembelajaran praktek pengelasan SMAW posisi 1G terdiri dari 4 pertemuan teori dan 13 pertemuan praktik; (2 model pembelajaran praktik pengelasan di SMKN 2 Pengasih sudah efektif tetapi untuk rutinitas pengelasan belum efektif untuk membentuk skill pengelasan SMAW posisi 1G dengan sistem assesment Asean Skill Welding Competition. Fasilitas utama dalam praktek pengelasan SMAW posisi 1G adalah mesin las. Sementara itu SMKN 2 pengasih memiliki 6 buah mesin las dengan rasio 1 mesin las untuk 5 orang siswa. Bahan habis pakai untuk 30 orang siswa per semester yang menggunakan model pembelajaran praktek pengelasan adalah besi plat ± 100-150 kg, mata gerinda total ± 5-6 keping, elektroda ± 9-10 box dan total waktunya aktif 77 jam selama satu semester. Kata kunci: pembelajaran Praktik Pengelasan SMAW, Skill Siswa untuk Posisi 1G LEARNING MODEL OF SHIELD METAL ARC WELDING (SMAW PRACTICE OF 1G POSITION AT THE WELDING ENGINEERING DEPARTMENT Abstract This research aimed to: (1 describe the learning model of shield metal arc welding (SMAW practice of 1G position at the Welding Engineering Department of State Vocational High School (SMKN 2 Pengasih; (2 find the effectiveness and describe materials needed in the learning model of shield metal arc welding (SMAW practice of 1G position, for examples

  14. Corrosion resistance of titanium ion implanted AZ91 magnesium alloy

    International Nuclear Information System (INIS)

    Liu Chenglong; Xin Yunchang; Tian Xiubo; Zhao, J.; Chu, Paul K.

    2007-01-01

    Degradable metal alloys constitute a new class of materials for load-bearing biomedical implants. Owing to their good mechanical properties and biocompatibility, magnesium alloys are promising in degradable prosthetic implants. The objective of this study is to improve the corrosion behavior of surgical AZ91 magnesium alloy by titanium ion implantation. The surface characteristics of the ion implanted layer in the magnesium alloys are examined. The authors' results disclose that an intermixed layer is produced and the surface oxidized films are mainly composed of titanium oxide with a lesser amount of magnesium oxide. X-ray photoelectron spectroscopy reveals that the oxide has three layers. The outer layer which is 10 nm thick is mainly composed of MgO and TiO 2 with some Mg(OH) 2 . The middle layer that is 50 nm thick comprises predominantly TiO 2 and MgO with minor contributions from MgAl 2 O 4 and TiO. The third layer from the surface is rich in metallic Mg, Ti, Al, and Ti 3 Al. The effects of Ti ion implantation on the corrosion resistance and electrochemical behavior of the magnesium alloys are investigated in simulated body fluids at 37±1 deg. C using electrochemical impedance spectroscopy and open circuit potential techniques. Compared to the unimplanted AZ91 alloy, titanium ion implantation significantly shifts the open circuit potential (OCP) to a more positive potential and improves the corrosion resistance at OCP. This phenomenon can be ascribed to the more compact surface oxide film, enhanced reoxidation on the implanted surface, as well as the increased β-Mg 12 Al 17 phase

  15. Corrosion properties and corrosion evolution of as-cast AZ91 alloy with rare earth yttrium

    International Nuclear Information System (INIS)

    Luo, T.J.; Yang, Y.S.

    2011-01-01

    Highlights: → Minor addition of Y will increase the corrosion resistance of AZ91 alloy, and 0.3 wt.% Y is the optimum addition. → A film composed of Mg(OH) 2 , MgCO 3 , Al(OH) 3 and Al 2 O 3 is formed on the surface of AZ91 alloy with rare earth Y free. → The film of AZ91 alloy with 0.3 wt.% Y is mainly composed of Mg(OH) 2 and MgCO 3 without any Al(OH) 3 and Al 2 O 3 . → The relative quantity of MgCO 3 in the surface film of AZ91 + 0.3 wt.% Y is bigger than that of AZ91 alloy with Y free. → Y 2 O 3 phase is found in the surface film of alloy III, which benefits to stabilize the surface film. -- Abstract: The corrosion resistance property and the corrosion evolution of as-cast AZ91 alloy with rare earth Y addition are investigated by using immersion tests, electrochemical impedance spectroscopy (EIS), and X-ray photoelectron spectroscopy (XPS). The results show that the proper amount of Y in the alloys can improve the corrosion resistance of AZ91 alloys effectively. With the increment of Y, the corrosion rate of the modified AZ91 alloys by Y addition was markedly less than that of AZ91 alloy. The corrosion rate of AZ91 alloy with 0.3 wt.% Y was the slightest, but further addition of Y content over 0.3 wt.% make the corrosion heavier. The XPS analysis suggests that the compound film of AZ91 alloy with 0.3 wt.% Y is mainly composed of Mg(OH) 2 and MgCO 3 without any Al(OH) 3 and Al 2 O 3 , in addition, Y 2 O 3 phase is found in the compound film of AZ91 alloy with 0.3 wt.% Y, which benefits to stabilize the surface film.

  16. Project W-211 Initial Tank Retrieval Systems (ITRS) Description of Operations for 241-AZ-102

    Energy Technology Data Exchange (ETDEWEB)

    BRIGGS, S.R.

    2000-02-25

    The primary purpose of the Initial Tank Retrieval Systems (ITRS) is to provide systems for retrieval of radioactive wastes stored in underground double-shell tanks (DSTs) for transfer to alternate storage, evaporation, pretreatment or treatment, while concurrently reducing risks associated with safety watch list and other DSTs. This Description of Operation (DOO) defines the control philosophy for the waste retrieval system for Tank 241-AZ-102 (AZ-102). This DOO provides a basis for the detailed design of the Project W-211 Retrieval Control System (RCS) for AZ-102 and also establishes test criteria for the RCS.

  17. Microstructure and Aging Behavior of Nonflammable AZ91D Mg Alloy

    OpenAIRE

    Seok Hong Min; Tae Kwon Ha

    2014-01-01

    Phase equilibria of AZ91D Mg alloys for nonflammable use, containing Ca and Y, were carried out by using FactSage® and FTLite database, which revealed that solid solution treatment could be performed at temperatures from 400 to 450oC. Solid solution treatment of AZ91D Mg alloy without Ca and Y was successfully conducted at 420oC and supersaturated microstructure with all beta phase resolved into matrix was obtained. In the case of AZ91D Mg alloy with some Ca and Y; howeve...

  18. Project W-211 Initial Tank Retrieval Systems (ITRS) Description of Operations for 241-AZ-102

    International Nuclear Information System (INIS)

    BRIGGS, S.R.

    2000-01-01

    The primary purpose of the Initial Tank Retrieval Systems (ITRS) is to provide systems for retrieval of radioactive wastes stored in underground double-shell tanks (DSTs) for transfer to alternate storage, evaporation, pretreatment or treatment, while concurrently reducing risks associated with safety watch list and other DSTs. This Description of Operation (DOO) defines the control philosophy for the waste retrieval system for Tank 241-AZ-102 (AZ-102). This DOO provides a basis for the detailed design of the Project W-211 Retrieval Control System (RCS) for AZ-102 and also establishes test criteria for the RCS

  19. Perangkat Lunak Untuk Analisis Gaya Gelombang Di Laboratorium Lingkungan Dan Energi Laut, Jurusan Teknik Kelautan, Ftk-Its

    Directory of Open Access Journals (Sweden)

    Fendi Hidayat

    2013-09-01

    Full Text Available Laboratorium Lingkungan dan Energi Laut, Jurusan Teknik Kelautan, FTK-ITS sering digunakan untuk pengujian. Salah satunya menguji gaya mooring pada floating breakwater. Hal tersebut menjadi salah satu alasan untuk membuat suatu perangkat lunak dalam membantu dalam proses analisis gaya mooring tersebut. Perangkat lunak yang dibuat berfungsi untuk membantu proses kalibrasi sensor load cell LUB-B 5 to 50 KB dan melakukan analisis gaya gelombang. Metode yang digunakan dalam penelitian ini adalah dengan menggunakan regresi linier, korelasi linier, perhitungan varian, standar deviasi, dan hukum Newton yang kemudian disusun dengan menggunakan Microsoft Visual Studio 2008. Penyusunan perangkat lunak yang bernama FORYS ini memiliki tampilan antarmuka pengguna yang mudah dalam pemakaian. Perangkat lunak yang telah dibuat juga bersifat portable sehingga bisa digunakan di berbagai komputer atau laptop. Hasil pengujian yang telah dilakukan menghasilkan bahwa semakin besar gaya gelombang yang terjadi, maka semakin besar pula tegangan yang terjadi pada tali.  

  20. EnviroAtlas - Phoenix, AZ - BenMAP Results by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 2,434 block groups in Phoenix, AZ. The US EPA's...

  1. EnviroAtlas - Phoenix, AZ - Meter-Scale Urban Land Cover (MULC) Data (2010)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The EnviroAtlas Phoenix, AZ Meter-Scale Urban Land Cover (MULC) data and map were generated from USDA NAIP (National Agricultural Imagery Program) four band (red,...

  2. Development of a Ballistic Specification for Magnesium Alloy AZ31B

    National Research Council Canada - National Science Library

    Jones, Tyrone L; DeLorme, Richard D

    2008-01-01

    The U.S. Army Research Laboratory (ARL) and Magnesium Elektron North America (MENA) have conducted a joint effort to develop and evaluate rolled plate in commercially available magnesium alloy-temper AZ31B-H24...

  3. Operational Test Report for the 241-AZ-101 Suspended Solids Profiler

    International Nuclear Information System (INIS)

    STENKAMP, D.M.

    2000-01-01

    This document comprises the Operational Test Report for the 241-AZ-101 Suspended Solids Profiler. This document presents the results of Operational Testing of the 241-AZ-101 Suspended Solids Profiler (SSP). Testing of the SSP was performed in accordance with OTP-260-005, ''SUSPENDED SOLIDS PROFILER OPERATIONAL TEST PROCEDURE''. The objective of the testing was to verify that all equipment and components functioned as designed, following construction completion and turnover to operations

  4. Microstructure and corrosion resistance of Ce–V conversion coating on AZ31 magnesium alloy

    International Nuclear Information System (INIS)

    Jiang, Xiao; Guo, Ruiguang; Jiang, Shuqin

    2015-01-01

    Highlights: • Through simple chemical conversion process, a Ce–V conversion coating is prepared on AZ31 magnesium alloy. The coating (∼2 μm thick) has a duplex structure and is composed of Mg, Al, Ce, V and O in the outer layer and Mg, Al, V, F and O in the inner layer. • The Ce–V conversion coating can increase the E corr by 157 mV and decrease the i corr by 80 times compared to AZ31 magnesium alloy substrate. Moreover, the performance of the Ce–V conversion coating excels the chromate conversion coating on AZ31 magnesium alloy. • The EIS results of Ce–V conversion coating indicate an increase of 10× in the corrosion resistance and a delay in the corrosion process kinetics compared to uncoated AZ31 magnesium alloy in 3.5 wt.% NaCl solution. • The ball cratering is a simple and effective technique of thickness measurement for chemical conversion coating. - Abstract: A Ce–V conversion coating was developed to improve the corrosion resistance of AZ31 magnesium alloy. Scanning electronic microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectrometer (XPS), grazing incidence X-ray diffraction (GIXRD) and the ball cratering test were adopted to study the morphology, chemical composition, structure and thickness of the coating. The coating has duplex structure with network and its thickness is about 2 μm. The coating contains high contents of Ce and V, which exhibits amorphous structure. Potentiodynamic polarization shows the coating can increase the corrosion potential and reduce the corrosion current density of AZ31 magnesium alloy. Moreover, the electrochemical impedance spectra exhibit the coating significantly improves the corrosion resistance of AZ31 magnesium alloy. Results indicate that the Ce–V conversion coating can provide effective protection to AZ31 magnesium alloy

  5. Microstructure and corrosion resistance of Ce–V conversion coating on AZ31 magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Xiao, E-mail: xiaoxiao217@126.com; Guo, Ruiguang; Jiang, Shuqin

    2015-06-30

    Highlights: • Through simple chemical conversion process, a Ce–V conversion coating is prepared on AZ31 magnesium alloy. The coating (∼2 μm thick) has a duplex structure and is composed of Mg, Al, Ce, V and O in the outer layer and Mg, Al, V, F and O in the inner layer. • The Ce–V conversion coating can increase the E{sub corr} by 157 mV and decrease the i{sub corr} by 80 times compared to AZ31 magnesium alloy substrate. Moreover, the performance of the Ce–V conversion coating excels the chromate conversion coating on AZ31 magnesium alloy. • The EIS results of Ce–V conversion coating indicate an increase of 10× in the corrosion resistance and a delay in the corrosion process kinetics compared to uncoated AZ31 magnesium alloy in 3.5 wt.% NaCl solution. • The ball cratering is a simple and effective technique of thickness measurement for chemical conversion coating. - Abstract: A Ce–V conversion coating was developed to improve the corrosion resistance of AZ31 magnesium alloy. Scanning electronic microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectrometer (XPS), grazing incidence X-ray diffraction (GIXRD) and the ball cratering test were adopted to study the morphology, chemical composition, structure and thickness of the coating. The coating has duplex structure with network and its thickness is about 2 μm. The coating contains high contents of Ce and V, which exhibits amorphous structure. Potentiodynamic polarization shows the coating can increase the corrosion potential and reduce the corrosion current density of AZ31 magnesium alloy. Moreover, the electrochemical impedance spectra exhibit the coating significantly improves the corrosion resistance of AZ31 magnesium alloy. Results indicate that the Ce–V conversion coating can provide effective protection to AZ31 magnesium alloy.

  6. Final results of double-shell tank 241-AZ-101 ultrasonic inspection

    International Nuclear Information System (INIS)

    JENSEN, C.E.

    1999-01-01

    This document presents the results and documentation of the nondestructive ultrasonic examination of tank 241-AZ-101. A tank inspection supplier was retained to provide and use an ultrasonic examination system (equipment, procedures, and inspectors) to scan a limited area of double-shell tank 241-AZ-101 primary tank wall and welds. The inspection found one reportable indication of thinning and no reportable pitting, corrosion, or cracking

  7. System Description for Tank 241-AZ-101 Waste Retrieval Data Acquisition System

    International Nuclear Information System (INIS)

    ROMERO, S.G.

    2000-01-01

    The proposed activity provides the description of the Data Acquisition System for Tank 241-AZ-101. This description is documented in HNF-5572, Tank 241-AZ-101 Waste Retrieval Data Acquisition System (DAS). This activity supports the planned mixer pump tests for Tank 241-AZ-101. Tank 241-AZ-101 has been selected for the first full-scale demonstration of a mixer pump system. The tank currently holds over 960,000 gallons of neutralized current acid waste, including approximately 12.7 inches of settling solids (sludge) at the bottom of the tank. As described in Addendum 4 of the FSAR (LMHC 2000a), two 300 HP mixer pumps with associated measurement and monitoring equipment have been installed in Tank 241-AZ-101. The purpose of the Tank 241-AZ-101 retrieval system Data Acquisition System (DAS) is to provide monitoring and data acquisition of key parameters in order to confirm the effectiveness of the mixer pumps utilized for suspending solids in the tank. The suspension of solids in Tank 241-AZ-101 is necessary for pretreatment of the neutralized current acid waste and eventual disposal as glass via the Hanford Waste Vitrification Plant. HNF-5572 provides a basic description of the Tank 241-AZ-101 retrieval system DAS, including the field instrumentation and application software. The DAS is provided to fulfill requirements for data collection and monitoring. This document is not an operations procedure or is it intended to describe the mixing operation. This USQ screening provides evaluation of HNF-5572 (Revision 1) including the changes as documented on ECN 654001. The changes include (1) add information on historical trending and data backup, (2) modify DAS I/O list in Appendix E to reflect actual conditions in the field, and (3) delete IP address in Appendix F per Lockheed Martin Services, Inc. request

  8. Acceptance Test Report for the 241-AZ-101 Ultrasonic Interface Level Analyzer

    International Nuclear Information System (INIS)

    ANDREWS, J.E.

    2000-01-01

    This document comprises the Acceptance Test Report for the 241-AZ-101 Ultrasonic Interface Level Analyzer. This document presents the results of Acceptance Testing of the 241-AZ-101 Ultrasonic Interface Level Analyzers (URSILLAs). Testing of the URSILLAs was performed in accordance with ATP-260-001, ''URSILLA Pre-installation Acceptance Test Procedure''. The objective of the testing was to verify that all equipment and components function in accordance with design specifications and original equipment manufacturer's specifications

  9. Influence of boron addition on the grain refinement and mechanical properties of AZ91 Mg alloy

    International Nuclear Information System (INIS)

    Suresh, M.; Srinivasan, A.; Ravi, K.R.; Pillai, U.T.S.; Pai, B.C.

    2009-01-01

    This article reports the effect of boron addition on the grain refinement efficiency and mechanical properties of AZ91 magnesium alloy. The results show that the addition of boron in the form of Al-4B master alloy, significantly refines the grain size of AZ91 alloy. This refinement is due to the presence of AlB 2 particles, which act as potential nucleants for Mg grains. Improved mechanical properties are obtained with the addition of boron due to the finer grains.

  10. Electrochemical corrosion behavior of AZ91D alloy in ethylene glycol

    International Nuclear Information System (INIS)

    Fekry, A.M.; Fatayerji, M.Z.

    2009-01-01

    The effect of concentration on the corrosion behavior of Mg-based alloy AZ91D was investigated in ethylene glycol-water solutions using electrochemical techniques i.e. potentiodynamic polarization, electrochemical impedance measurements (EIS) and surface examination via scanning electron microscope (SEM) technique. This can provide a basis for developing new coolants for magnesium alloy engine blocks. Corrosion behavior of AZ91D alloy by coolant is important in the automotive industry. It was found that the corrosion rate of AZ91D alloy decreased with increasing concentration of ethylene glycol. For AZ91D alloy in chloride >0.05 M or fluoride 0.05 M for fluoride containing ethylene glycol solution, some inhibition effect has been observed. The corrosion of AZ91D alloy in the blank can be effectively inhibited by addition of 0.05 mM paracetamol that reacts with AZ91D alloy and forms a protective film on the surface at this concentration as confirmed by surface examination.

  11. Effect of mechanical vibrations on the wear behavior of AZ91 Mg alloy

    Science.gov (United States)

    Chaturvedi, V.; Pandel, U.; Sharma, A.

    2018-02-01

    AZ91 Mg alloy is the most promising alloy used for structural applications. The vibration induced methods are effective and economic viable in term of mechanical properties. Sliding wear tests were performed on AZ91 Mg alloy using a pin-on- disc configuration. Wear rates were measured at 5 N and 10N at a sliding velocity of 1m/s for varied frequency within the range of 5- 25Hz and a constant amplitude of 2mm. Microstructures of worn surfaces and wear debris were characterized by field emission scanning electron microscopy (FESEM). It is observed that wear resistance of vibrated AZ91 alloy at 15Hz frequency ad 2mm amplitude was superior than cast AZ91 Mg alloy. Finer grain size and equiaxed grain shape both are important parameters for better wear resistance in vibrated AZ91 Mg alloys. FESEM analysis revealed that wear is considerably affected due to frictional heat generated by the relative motion between AZ91 Mg alloy and EN31 steel surface. No single mechanism was responsible for material loss.

  12. Effect of aluminum coatings on corrosion properties of AZ31 magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Chiu Liuho; Lin Hsingan; Chen Chunchin; Yang Chihfu [Dept. of materials engineering, Tatung Univ., Taipei (Taiwan); Chang Chiahua; Wu Jenchin [Physical chemistry section, chemical systems research div., Chung-Shan Inst. of Science and Technology, Tao-Yuan (Taiwan)

    2003-07-01

    This investigation aimed to increase the corrosion resistance of an AZ31 magnesium alloy by an aluminum arc spray coating and a post-treatment consisted of hot pressing and anodizing. It was found that the aluminum arc spraying alone was incapable of protection against corrosion due to the high amount of pores present in the coating layer. In order to solve the problem, densification of the Al arc-sprayed layer was carried out by hot pressing the coated AZ31 Mg alloy plate under an appropriate range of temperature, time and pressure. After hot pressing the Al coated AZ31 Mg alloy plate exhibited a much improved corrosion resistance. A final anodizing treatment applied to the AZ31 alloy with the dense Al coating further improved its resisting to corrosion. The results showed that, by adopting the Al arc spraying, hot pressing and anodizing process, the corrosion current density of the AZ31 alloy in a 3.5 wt% NaCl solution was from 2.1 x 10{sup -6} A/cm{sup 2} (original AZ31) to 3.7 x 10{sup -7} A/cm{sup 2} (after the surface treatment), which value is close to that of an anodized aluminum plate. (orig.)

  13. Electrochemical corrosion behavior of AZ91D alloy in ethylene glycol

    Energy Technology Data Exchange (ETDEWEB)

    Fekry, A.M. [Chemistry Department, Faculty of Science, Cairo University, Giza 12613 (Egypt)], E-mail: hham4@hotmail.com; Fatayerji, M.Z. [Chemistry Department, Faculty of Science, Cairo University, Giza 12613 (Egypt)

    2009-11-01

    The effect of concentration on the corrosion behavior of Mg-based alloy AZ91D was investigated in ethylene glycol-water solutions using electrochemical techniques i.e. potentiodynamic polarization, electrochemical impedance measurements (EIS) and surface examination via scanning electron microscope (SEM) technique. This can provide a basis for developing new coolants for magnesium alloy engine blocks. Corrosion behavior of AZ91D alloy by coolant is important in the automotive industry. It was found that the corrosion rate of AZ91D alloy decreased with increasing concentration of ethylene glycol. For AZ91D alloy in chloride >0.05 M or fluoride <0.05 M containing 30% ethylene glycol solution, they are more corrosive than the blank (30% ethylene glycol-70% water). However, at concentrations <0.05 for chloride or >0.05 M for fluoride containing ethylene glycol solution, some inhibition effect has been observed. The corrosion of AZ91D alloy in the blank can be effectively inhibited by addition of 0.05 mM paracetamol that reacts with AZ91D alloy and forms a protective film on the surface at this concentration as confirmed by surface examination.

  14. Effect of rare earth elements on high cycle fatigue behavior of AZ91 alloy

    International Nuclear Information System (INIS)

    Mokhtarishirazabad, M.; Boutorabi, S.M.A.; Azadi, M.; Nikravan, M.

    2013-01-01

    This article investigates effects of adding rare earth elements (RE) into a magnesium–aluminum–zinc alloy (the AZ91 alloy) on its high cycle fatigue (HCF) behavior. For this purpose, AZ91 and AZ91+1% RE (AZE911) alloys were gravity casted in a metallic die. RE elements were added to the AZ91 alloy in the form of mischmetals. Microscopic evaluations with the scanning electron microscopy (SEM) and mechanical tests include tensile, hardness and HCF behaviors, were performed on prepared samples. Rotary bending fatigue tests were carried out at a stress ratio (R) of −1 and a frequency of 125 Hz, at the room temperature, in the air. The microscopic investigation demonstrates that the addition of 1% RE elements leads to the formation of Al 11 RE 3 intermetallic particles which is associated to the reduction of β-(Mg 17 Al 12 ) phases. Results of mechanical experiments suggest a negligible effect of adding 1% RE elements on mechanical properties of the AZ91 alloy. Curves of stress-life (S–N) shows an increase in the fatigue strength at 10 5 cycles, from 100±10 MPa to 135±10 MPa, when RE elements were added to the AZ91 alloy

  15. Effect of rare earth elements on high cycle fatigue behavior of AZ91 alloy

    Energy Technology Data Exchange (ETDEWEB)

    Mokhtarishirazabad, M., E-mail: mehdi-mokhtari@hotmail.com [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Boutorabi, S.M.A. [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Azadi, M.; Nikravan, M. [Irankhodro Powertrain Company (IPCO), Tehran (Iran, Islamic Republic of)

    2013-12-10

    This article investigates effects of adding rare earth elements (RE) into a magnesium–aluminum–zinc alloy (the AZ91 alloy) on its high cycle fatigue (HCF) behavior. For this purpose, AZ91 and AZ91+1% RE (AZE911) alloys were gravity casted in a metallic die. RE elements were added to the AZ91 alloy in the form of mischmetals. Microscopic evaluations with the scanning electron microscopy (SEM) and mechanical tests include tensile, hardness and HCF behaviors, were performed on prepared samples. Rotary bending fatigue tests were carried out at a stress ratio (R) of −1 and a frequency of 125 Hz, at the room temperature, in the air. The microscopic investigation demonstrates that the addition of 1% RE elements leads to the formation of Al{sub 11}RE{sub 3} intermetallic particles which is associated to the reduction of β-(Mg{sub 17}Al{sub 12}) phases. Results of mechanical experiments suggest a negligible effect of adding 1% RE elements on mechanical properties of the AZ91 alloy. Curves of stress-life (S–N) shows an increase in the fatigue strength at 10{sup 5} cycles, from 100±10 MPa to 135±10 MPa, when RE elements were added to the AZ91 alloy.

  16. UBV Photometry at the Outside Eclipse Phase of AZ Cassiopeiae

    Directory of Open Access Journals (Sweden)

    Il-Seong Nha

    1994-06-01

    Full Text Available VV Cep-type long period spectroscopic-eclipsing binary AZ Cas has been observed for five years, 1985 Oct ~ 1990 Feb, in UBV at the Ilsan Station of Yonsei University Observatory. A total of 431 observations (U=129, B=142 and V=160 are made for 86 nights. Instrumental differential UBV and B-V light curves made with these observations cover phases nearly a half of one period. There is no appreciable light variation in V but in other two passbands a gradual decrease of the brightness is clearly noticed. The loss of light in B resulted in a reddening in △(B-V by +0.06 at phases between 0.4~0.5 as compared with that of at phase ~0.1. This intrinsic reddening arouses a question why at the orbital phase of the transit of a hot star in front of a cool M supergiant the heating of the facing hemisphere of M supergiant by the strong radiation from the B star is absent. With regard to this unusual situation we propose a hypothesis that a large amount of gas stream of low temperature ejected from the surface of M supergiant component towards the B star dominates the brightness of B star and reflection effect.

  17. CYCLIC FATIGUE RESISTANCE OF AZ91 MAGNESIUM ALLOY

    Directory of Open Access Journals (Sweden)

    Aneta Němcová

    2009-11-01

    Full Text Available The paper deals with determination of principal mechanical properties and the investigation of fatigue behaviour of AZ91 magnesium alloy. The experimental material was made by squeeze casting technique and heat treated to obtain T4 state (solution annealing, when hard, brittle Mg17Al12 intermetallic phase is dissolved. The basic mechanical properties (Young’s modulus, ultimate tensile strength, yield strength, elongation to fracture and reduction of area were determined by static tensile test. Furthermore, fatigue parameters were investigated. The S-N curve on the basis of smooth test bars tested under symmetrical push-pull loading at room temperature was evaluated. The measured data were subsequently used for fitting with suitable regression functions (Kohout & Věchet and Stromeyer for determination of the fatigue parameters. Fatigue limit sigma-c of the studied alloy for 108 cycles is approaching 50 MPa. In addition, the fracture surfaces were observed by scanning electron microscopy. The failure analysis proved that the striations were observed in fatigue crack propagation area and in the area of static fracture was observed the transgranular ductile fracture. The structure of the studied alloy in the basic state and after heat treatment was observed by light and scanning electron microscopy.

  18. AzTEC on ASTE Survey of Submillimeter Galaxies

    Science.gov (United States)

    Kohno, K.; Tamura, Y.; Hatsukade, B.; Nakanishi, K.; Iono, D.; Takata, T.; Wilson, G. W.; Yun, M. S.; Perera, T.; Austermann, J. E.; Scott, K. S.; Hughes, H.; Aretxaga, I.; Tanaka, K.; Oshima, T.; Yamaguchi, N.; Matsuo, H.; Ezawa, H.; Kawabe, R.

    2008-10-01

    We have conducted an unprecedented survey of submillimeter galaxies (SMGs) using the 144 pixel bolometer camera AzTEC mounted on the ASTE 10-m dish in Chile. We have already obtained many (>20) wide (typically 12' × 12' or wider) and deep (1 σ sensitivity of 0.5-1.0 mJy) 1.1 mm continuum images of known blank fields and over-density regions/protoclusters across a wide range of redshifts with a spatial resolution of ˜ 30''. It has resulted in the numerous (˜ a few 100, almost equivalent to the total number of the previously known SMGs) new and secure detections of SMGs. In this paper, we present initial results of two selected fields, SSA 22 and AKARI Deep Field South (ADF-S). A significnat clustering of bright SMGs toward the density peak of LAEs is found in SSA 22. We derived the differential and cumulative number counts from the detected sources in ADF-S, which probe the faintest flux densities (down to ˜1 mJy) among 1-mm blank field surveys to date.

  19. The effects of alloying elements on microstructures and mechanical properties of tungsten inert gas welded AZ80 magnesium alloys joint

    Science.gov (United States)

    Li, Hui; Zhang, Jiansheng; Ding, Rongrong

    2017-11-01

    The effects of alloying elements on the macrostructures, microstructures and tensile strength of AZ80 Mg alloy weldments were studied in the present study. The results indicate that with the decrease of Al element content of filler wire, the welding defects of seam are gradually eliminated and the β-Mg17Al12 phases at α-Mg boundaries are refined and become discontinuous, which are beneficial to the improvement of tensile strength. With AZ31 Mg alloy filler wire, the maximum tensile strength of AZ80 weldment is 220 MPa and fracture occurs at the welding seam of joint. It is experimentally proved that robust AZ80 Mg alloy joints can be obtained by tungsten inert gas (TIG) welding process with AZ31 Mg alloy filler wire. However, further study is required to improve the microstructures and reduce welding defects of joint in order to further improve the joining strength of AZ80 Mg alloy joint.

  20. Peningkatan Kemampuan Memahami Bacaan Bahasa Arab Melalui Teknik Pembelajaran SQ4-R (Penelitian Tindakan pada Mahasiswa Pendidikan Bahasa Arab Jurusan Tarbiyah STAIN Kendari)

    OpenAIRE

    Batmang, Batmang

    2013-01-01

    Tujuan dari penelitian ini adalah untuk meningkatkan kemampuan siswa pada semester ke enam Departemen Arab Bahasa Pendidikan Akademik 2012-2013 dalam memahami teks-teks Arab dengan penerapan teknik pembelajaran SQ4-R. Penelitian ini merupakan penelitian tindakan dan pendekatan kualitatif. Metode untuk mengumpulkan data yang: observasi, wawancara, portofolio, membaca tes pemahaman, dan catatan lapangan. Data dianalisis secara kualitatif dengan mengurangi, menyajikan dan dengan menarik kesimpul...

  1. Penerapan european foundation for quality management’s (efqm excellence model pada sistem pengukuran kinerja jurusan Teknik Mesin Universitas Udayana

    Directory of Open Access Journals (Sweden)

    I Made Dwi Budiana Penindra

    2018-01-01

    Full Text Available Abstrak Globalisasi merupakan fenomena yang tidak dapat dihindari dalam tata kehidupan kita dimana persaingan antar negara semakin terbuka terutama pada bidang sumber daya manusia. Untuk menghadapi keadaan tersebut maka perguruan tinggi diharapkan menjadi pusat penyelenggaraan dan pengembangan pendidikan tinggi yang menghasilkan manfaat dan meningkatkan mutu kehidupan bermasyarakat, berbangsa dan bernegara. Jurusan Teknik Mesin adalah salah satu jurusan yang telah mendapatkan akreditasi A dari BAN PT dimana saat ini baru 20% jurusan yang terakreditasi di lingkungan Unuversitas Udayana. Didalam meningkatkan kinerja perlu kiranya dirancang suatu sistem pengukuran kinerja yang terintegrasi dimana saat ini Jurusan Teknik Mesin belum memiliki sistem pengukuran kinerja yang baik. Dalam menyempurnakan sistem pengukuran kinerja yang telah ada, maka akan dilakukan Analisis, perancangan dan implementasi sistem pengukuran kinerja dengan European Foundation for Quality Management’s (EFQM Execellence Model dimana metode tersebut diintregasikan dengan beberapa metode yaitu Metode Objectives Matrix (OMAX, Integrated Performance Measurement Systems (IPMS, dan Analytical Hierarcy Process (AHP pada Jurusan Teknik Mesin Universitas Udayana. Langkah-langkah atau rincian dari metode penelitian yang diharapkan adalah mengikuti tahapan sebagai berikut : Pemilihan Metode Pengukuran Produktivitas, Jenis dan Metode Pengumpulan Data, Identifikasi Indikator-Indikator atau Kriteria Produktivitas yang Akan Diukur, Pemberian Bobot Dari Masing-Masing KPI Yang Diukur, Pengolahan Data Atau Pengukuran Kriteria Produktivitas, Evaluasi Produktivitas. Dari hasil penelitian dapat disimpulkan bahwa Implementasi Sistem Pengukuran Kinerja dengan European Foundation for Quality Management’s (EFQM Execellence Model yang diintegrasikan Integrated Performance Measurement Systems (IPMS dan Metode Objectives Matrix (OMAX memiliki perbedaan pandangan pada penentuan stakeholder requirement

  2. A study on the relationships between corrosion properties and chemistry of thermally oxidised surface films formed on polished commercial magnesium alloys AZ31 and AZ61

    International Nuclear Information System (INIS)

    Feliu, Sebastián; Samaniego, Alejandro; Barranco, Violeta; El-Hadad, A.A.; Llorente, Irene; Serra, Carmen; Galván, J.C.

    2014-01-01

    Highlights: • Surface chemistry of heat treated magnesium alloys. • Relation between heat treatment and aluminium subsurface enrichment. • Relation between surface composition and corrosion behaviour. - Abstract: This paper studies the changes in chemical composition of the thin oxide surface films induced by heating in air at 200 °C for time intervals from 5 min to 60 min on the freshly polished commercial AZ31 and AZ61 alloys with a view to better understanding their protective properties. This thermal treatment resulted in the formation of layers enriched in metallic aluminium at the interface between the outer MgO surface films and the bulk material. A strong link was found between the degree of metallic Al enrichment in the subsurface layer (from 10 to 15 at.%) observed by XPS (X-ray photoelectron spectroscopy) in the AZ61 treated samples and the increase in protective properties observed by EIS (electrochemical impedance spectroscopy) in the immersion test in 0.6 M NaCl. Heating for 5–60 min in air at 200 °C seems to be an effective, easy to perform and inexpensive method for increasing the corrosion resistance of the AZ61 alloy by approximately two or three times

  3. A study on the relationships between corrosion properties and chemistry of thermally oxidised surface films formed on polished commercial magnesium alloys AZ31 and AZ61

    Energy Technology Data Exchange (ETDEWEB)

    Feliu, Sebastián, E-mail: sfeliu@cenim.csic.es [Centro Nacional de Investigaciones Metalúrgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain); Samaniego, Alejandro [Centro Nacional de Investigaciones Metalúrgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain); Barranco, Violeta [Instituto de Ciencias de Materiales de Madrid, ICMM, Consejo Superior de Investigaciones Científicas, CSIC, Sor Juana Inés de la Cruz, 3, Cantoblanco, 28049, Madrid (Spain); El-Hadad, A.A. [Physics Department, Faculty of Science, Al-Azhar University, Nasr City 11884, Cairo (Egypt); Llorente, Irene [Centro Nacional de Investigaciones Metalúrgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain); Serra, Carmen [Servicio de Nanotecnologia y Análisis de Superficies, CACTI, Universidade de Vigo, 36310 Vigo (Spain); Galván, J.C. [Centro Nacional de Investigaciones Metalúrgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain)

    2014-03-01

    Highlights: • Surface chemistry of heat treated magnesium alloys. • Relation between heat treatment and aluminium subsurface enrichment. • Relation between surface composition and corrosion behaviour. - Abstract: This paper studies the changes in chemical composition of the thin oxide surface films induced by heating in air at 200 °C for time intervals from 5 min to 60 min on the freshly polished commercial AZ31 and AZ61 alloys with a view to better understanding their protective properties. This thermal treatment resulted in the formation of layers enriched in metallic aluminium at the interface between the outer MgO surface films and the bulk material. A strong link was found between the degree of metallic Al enrichment in the subsurface layer (from 10 to 15 at.%) observed by XPS (X-ray photoelectron spectroscopy) in the AZ61 treated samples and the increase in protective properties observed by EIS (electrochemical impedance spectroscopy) in the immersion test in 0.6 M NaCl. Heating for 5–60 min in air at 200 °C seems to be an effective, easy to perform and inexpensive method for increasing the corrosion resistance of the AZ61 alloy by approximately two or three times.

  4. A study on the relationships between corrosion properties and chemistry of thermally oxidised surface films formed on polished commercial magnesium alloys AZ31 and AZ61

    Science.gov (United States)

    Feliu, Sebastián; Samaniego, Alejandro; Barranco, Violeta; El-Hadad, A. A.; Llorente, Irene; Serra, Carmen; Galván, J. C.

    2014-03-01

    This paper studies the changes in chemical composition of the thin oxide surface films induced by heating in air at 200 °C for time intervals from 5 min to 60 min on the freshly polished commercial AZ31 and AZ61 alloys with a view to better understanding their protective properties. This thermal treatment resulted in the formation of layers enriched in metallic aluminium at the interface between the outer MgO surface films and the bulk material. A strong link was found between the degree of metallic Al enrichment in the subsurface layer (from 10 to 15 at.%) observed by XPS (X-ray photoelectron spectroscopy) in the AZ61 treated samples and the increase in protective properties observed by EIS (electrochemical impedance spectroscopy) in the immersion test in 0.6 M NaCl. Heating for 5-60 min in air at 200 °C seems to be an effective, easy to perform and inexpensive method for increasing the corrosion resistance of the AZ61 alloy by approximately two or three times.

  5. TEKNIK PENGATURAN AIR PADA INTENSIFIKASI PADI AEROB TERKENDALI-BERBASIS ORGANIK (IPAT-BO UNTUK MENINGKATKAN POPULASI RHIZOBACTERIA, EFISIENSI PENGGUNAAN AIR, PERAKARAN TANAMAN, DAN HASIL TANAMAN PADI

    Directory of Open Access Journals (Sweden)

    Hingdri -

    2013-03-01

    Full Text Available Teknik pengaturan air pada budidaya tanaman padi melalui Intensifikasi Padi Aerob Terkendali-Berbasis Organik (IPAT-BO perlu dilakukan untuk meningkatkan efisiensi penggunaan air. Penelitian ini bertujuan untuk mengtahui aktivitas rhizobacteria, tingkat efisiensi penggunaan air, perkaran tanaman, dan hasil tanaman pada berbagai teknik pengaturan air.Penelitian dilaksanakan di lahan percobaan Fakultas Pertanian Universitas Winaya Mukti, Tanjungsari pada inceptisol pada skala pot plastik. Rancangan percobaan yang digunakan adalah Rancangan Acak Kelompok (RAK faktor tunggal dengan 16 perlakuan dan diulang tiga kali, yaitu terdiri dari kombinasi antara perlakuan air dan empat varietas. Perlakuan air: tinggi muka air + 5cm, 0 cm, – 5 cm dan  – 10 cm. Empat varietas: Ciherang, Sintanur, Inpari 13 dan Fatmawati..Hasil penelitian menunjukkan terdapat pengaruhnyata terhadap populasi Rhizobacteria, perkembangan akar, dan hasil tanaman. Perlakuan tinggi muka air – 10 cm varietas Fatmawati memberikan hasil tertinggi pada volume akar 186,67 ml, populasi bakteri Azotobacter sp. (1,43 x 1010 CFU g-1, bakteri pelarut fosfat (6,07 x 108 CFU g-1, hasil tanaman tertinggi 95,9 g rumpun-1 setara dengan 9,14 ton ha-1 serta meningkatkan efisiensi penggunaan air 47,1 % dibandingkan dengan pengenangan 5 cm.Kata kunci:  Teknik pengaturan air, efisiensi penggunaan air, IPAT-BO, populasi rhizobakteria

  6. Study on fused/cast AZS refractories for deployment in vitrification of radioactive waste effluents

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, Pranesh, E-mail: praneshsengupta@gmail.com [Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Mishra, R.K.; Soudamini, N. [Waste Management Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Sen, D.; Mazumder, S. [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Kaushik, C.P. [Waste Management Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Ajithkumar, T.G. [Central NMR Facility, National Chemical Laboratory, Pune 411 008 (India); Banerjee, K. [Nuclear Recycle Group, Mumbai 400 085 (India)

    2015-12-15

    ‘Fused/cast Al{sub 2}O{sub 3}–ZrO{sub 2}–SiO{sub 2} (FC-AZS)’ is being considered as ‘glass contact refractory’ within ceramic melters, to be used for nuclear waste immobilization. Microstructural analyses reveal random distributions of baddeleyite (ZrO{sub 2}) within aluminosilicate (Al{sub 2}SiO{sub 5}) matrix. {sup 27}Al and {sup 29}Si NMR data suggest that within aluminosilicate matrix Al occurs in both 4- and 6-fold co-ordinations whereas Si prefers a 4-fold environment. Polydispersity of pores has been studied with small-angle neutron scattering (SANS) technique. Corrosion rates of FC-AZS within 6 M HNO{sub 3}, simulated wastes (500 h exposure), and borosilicate melt (975 °C, 800 h exposure) are found to be 0.38 × 10{sup 3} μmy{sup −1}, 0.13 × 10{sup 3} μmy{sup −1} and 4.75 × 10{sup 3} μmy{sup −1} respectively. A comparison of chemical interaction data clearly suggests that FC-AZS exhibits better chemical durability than AZC refractory (Al{sub 2}O{sub 3}–ZrO{sub 2}–Cr{sub 2}O{sub 3}, also used for similar purpose). Thermal cycling studies indicate that FC-AZS retains structural integrity (including compressive strength and density) even up to 20 cycles. - Highlights: • Vitrification of nuclear waste using AZS refractory within ceramic melter. • Microstructure of AZS refractory. • Interaction of AZS with simulated high level waste and glass.

  7. Rapid coating of AZ31 magnesium alloy with calcium deficient hydroxyapatite using microwave energy

    International Nuclear Information System (INIS)

    Ren, Yufu; Zhou, Huan; Nabiyouni, Maryam; Bhaduri, Sarit B.

    2015-01-01

    Due to their unique biodegradability, magnesium alloys have been recognized as suitable metallic implant materials for degradable bone implants and bioresorbable cardiovascular stents. However, the extremely high degradation rate of magnesium alloys in physiological environment has restricted its practical application. This paper reports the use of a novel microwave assisted coating technology to improve the in vitro corrosion resistance and biocompatibility of Mg alloy AZ31. Results indicate that a dense calcium deficient hydroxyapatite (CDHA) layer was uniformly coated on a AZ31 substrate in less than 10 min. Weight loss measurement and SEM were used to evaluate corrosion behaviors in vitro of coated samples and of non-coated samples. It was seen that CDHA coatings remarkably reduced the mass loss of AZ31 alloy after 7 days of immersion in SBF. In addition, the prompt precipitation of bone-like apatite layer on the sample surface during immersion demonstrated a good bioactivity of the CDHA coatings. Proliferation of osteoblast cells was promoted in 5 days of incubation, which indicated that the CDHA coatings could improve the cytocompatibility of the AZ31 alloy. All the results suggest that the CDHA coatings, serving as a protective layer, can enhance the corrosion resistance and biological response of magnesium alloys. Furthermore, this microwave assisted coating technology could be a promising method for rapid surface modification of biomedical materials. - Highlights: • A microwave assisted coating process for biodegradable Mg alloy. • CDHA coatings were successfully developed on AZ31 alloy in minutes. • The as-deposited CDHA coatings significantly reduced the degradation rate of AZ31 alloy. • The CDHA coated AZ31 alloy showed good bioactivity and biocompatibility in vitro. • The microwave assisted coating process can be used as rapid surface modification for bioimplants

  8. Rapid coating of AZ31 magnesium alloy with calcium deficient hydroxyapatite using microwave energy

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Yufu, E-mail: Yufu.Ren@rockets.utoledo.edu [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Zhou, Huan [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Institute of Biomedical Engineering and Health Sciences, Changzhou University, Changzhou, Jiangsu (China); Nabiyouni, Maryam [Department of Bioengineering, The University of Toledo, Toledo, OH (United States); Bhaduri, Sarit B. [Department of Mechanical, Industrial and Manufacturing Engineering, The University of Toledo, Toledo, OH (United States); Division of Dentistry, The University of Toledo, Toledo, OH (United States)

    2015-04-01

    Due to their unique biodegradability, magnesium alloys have been recognized as suitable metallic implant materials for degradable bone implants and bioresorbable cardiovascular stents. However, the extremely high degradation rate of magnesium alloys in physiological environment has restricted its practical application. This paper reports the use of a novel microwave assisted coating technology to improve the in vitro corrosion resistance and biocompatibility of Mg alloy AZ31. Results indicate that a dense calcium deficient hydroxyapatite (CDHA) layer was uniformly coated on a AZ31 substrate in less than 10 min. Weight loss measurement and SEM were used to evaluate corrosion behaviors in vitro of coated samples and of non-coated samples. It was seen that CDHA coatings remarkably reduced the mass loss of AZ31 alloy after 7 days of immersion in SBF. In addition, the prompt precipitation of bone-like apatite layer on the sample surface during immersion demonstrated a good bioactivity of the CDHA coatings. Proliferation of osteoblast cells was promoted in 5 days of incubation, which indicated that the CDHA coatings could improve the cytocompatibility of the AZ31 alloy. All the results suggest that the CDHA coatings, serving as a protective layer, can enhance the corrosion resistance and biological response of magnesium alloys. Furthermore, this microwave assisted coating technology could be a promising method for rapid surface modification of biomedical materials. - Highlights: • A microwave assisted coating process for biodegradable Mg alloy. • CDHA coatings were successfully developed on AZ31 alloy in minutes. • The as-deposited CDHA coatings significantly reduced the degradation rate of AZ31 alloy. • The CDHA coated AZ31 alloy showed good bioactivity and biocompatibility in vitro. • The microwave assisted coating process can be used as rapid surface modification for bioimplants.

  9. Effect of the chemistry and structure of the native oxide surface film on the corrosion properties of commercial AZ31 and AZ61 alloys

    Energy Technology Data Exchange (ETDEWEB)

    Feliu, Sebastian, E-mail: sfeliu@cenim.csic.es [Centro Nacional de Investigaciones Metalurgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain); Maffiotte, C. [CIEMAT-DT edificio 30, Avda. Complutense, 22, 28040 Madrid (Spain); Samaniego, A.; Galvan, Juan Carlos [Centro Nacional de Investigaciones Metalurgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain); Barranco, Violeta [Centro Nacional de Investigaciones Metalurgicas CSIC, Avda. Gregorio del Amo 8, 28040 Madrid (Spain); Instituto de Ciencias de Materiales de Madrid, ICMM, Consejo Superior de Investigaciones Cientificas, CSIC, Sor Juana Ines de la Cruz, 3, Cantoblanco, 28049, Madrid (Spain)

    2011-08-01

    The purpose of this study has been to advance in knowledge of the chemical composition, structure and thickness of the thin native oxide film formed spontaneously in contact with the laboratory atmosphere on the surface of freshly polished commercial AZ31 and AZ61 alloys with a view to furthering the understanding of protection mechanisms. For comparative purposes, and to more fully describe the behaviour of the native oxide film, the external oxide films formed as a result of the manufacturing process (as-received condition) have been characterised. The technique applied in this research to study the thin oxide films (thickness of just a few nanometres) present on the surface of the alloys has basically been XPS (X-ray photoelectron spectroscopy) in combination with ion sputtering. Corrosion properties of the alloys were studied in 0.6 M NaCl by measuring charge transfer resistance values, which are deduced from EIS (electrochemical impedance spectroscopy) measurements after 1 h of exposure. Alloy AZ61 generally showed better corrosion resistance than AZ31, and the freshly polished alloys showed better corrosion resistance than the alloys in as-received condition. This is attributed to a combination of (1) higher thickness of the native oxide film on the AZ61 alloy and (2) greater uniformity of the oxide film in the polished condition. The formation of an additional oxide layer composed by a mixture of spinel (MgAl{sub 2}O{sub 4}) and MgO seems to diminish the protective properties of the passive layer on the surface of the alloys in as-received condition.

  10. Effect of the chemistry and structure of the native oxide surface film on the corrosion properties of commercial AZ31 and AZ61 alloys

    International Nuclear Information System (INIS)

    Feliu, Sebastian; Maffiotte, C.; Samaniego, A.; Galvan, Juan Carlos; Barranco, Violeta

    2011-01-01

    The purpose of this study has been to advance in knowledge of the chemical composition, structure and thickness of the thin native oxide film formed spontaneously in contact with the laboratory atmosphere on the surface of freshly polished commercial AZ31 and AZ61 alloys with a view to furthering the understanding of protection mechanisms. For comparative purposes, and to more fully describe the behaviour of the native oxide film, the external oxide films formed as a result of the manufacturing process (as-received condition) have been characterised. The technique applied in this research to study the thin oxide films (thickness of just a few nanometres) present on the surface of the alloys has basically been XPS (X-ray photoelectron spectroscopy) in combination with ion sputtering. Corrosion properties of the alloys were studied in 0.6 M NaCl by measuring charge transfer resistance values, which are deduced from EIS (electrochemical impedance spectroscopy) measurements after 1 h of exposure. Alloy AZ61 generally showed better corrosion resistance than AZ31, and the freshly polished alloys showed better corrosion resistance than the alloys in as-received condition. This is attributed to a combination of (1) higher thickness of the native oxide film on the AZ61 alloy and (2) greater uniformity of the oxide film in the polished condition. The formation of an additional oxide layer composed by a mixture of spinel (MgAl 2 O 4 ) and MgO seems to diminish the protective properties of the passive layer on the surface of the alloys in as-received condition.

  11. Fatigue life of the casting-magnesium alloy AZ91

    International Nuclear Information System (INIS)

    Eisenmeier, G.; Mughrabi, H.; Holzwarth, B.; Hoeppel, H.W.; Ding, H.Z.

    2000-01-01

    The cyclic deformation behaviour of the die-casting magnesium alloy AZ91 was investigated at constant total strain amplitudes between 1.4 x 10 -3 and 2 x 10 -2 at room temperature (20 C) and at 130 C. At low total strain amplitudes, a weak cyclic softening at the beginning of the fatigue tests is followed by cyclic hardening, whereas at high total strain amplitudes a strong cyclic hardening occurs throughout. The fatigue lives at 130 C are slightly longer at high strain amplitudes but shorter at low strain amplitudes than at room temperature. The fatigue life data for both temperatures can be described well by the laws of Manson-Coffin and Basquin. The microstructural investigations performed show the strong influence of several microstructural features on the initiation and propagation of fatigue cracks. In order to understand the fatigue crack propagation behaviour, fatigue tests were interrupted at certain numbers of cycles in order to make replicas of the surface of the samples. It could be verified that crack propagation occurs mainly by the coalescence of smaller cracks. Furthermore, unloading tests, performed within a closed cycle, were carried out in order to capture the changes of stiffness (compliance) during a closed cycle with the aim to ascertain the damage evolution occurring during the fatigue tests and to determine the stresses at which the cracks open and close. Finally, two-step fatigue tests were carried out with the objective to quantify deviations from the linear damage rule (LDR) of Palmgren and Miner. The results obtained in this study will be used to formulate a microstructurally based life-prediction concept for single-step as well as for two-step fatigue loading. (orig.)

  12. Dose rate analysis for Tank 101 AZ (Project W151)

    International Nuclear Information System (INIS)

    Schwarz, R.A.; Hillesland, K.E.; Carter, L.L.

    1994-11-01

    This document describes the expected dose rates for modification to tank 101 AZ including modifications to the steam coil, mixer pump, and temperature probes. The thrust of the effort is to determine dose rates from: modification of a steam coil and caisson; the installation of mixer pumps; the installation of temperature probes; and estimates of dose rates that will be encountered while making these changes. Because the dose rates for all of these configurations depend upon the photon source within the supernate and sludge, comparisons were also made between measured dose rates within a drywell and the corresponding calculated dose rates. The calculational tool used is a Monte Carlo (MCNP 2 ) code since complicated three dimensional geometries are involved. A summary of the most important results of the entire study is given in Section 2. The basic calculational geometry model of the tank is discussed in Section 3, along with a tabulation of the photon sources that were used within the supernate and the sludge, and a discussion of uncertainties. The calculated dose rates around the steam coil and caisson before and after modification are discussed in Section 4. The configuration for the installation of the mixer pumps and the resulting dose rates are given in Section 5. The predicted changes in dose rates due to a possible dilution of the supernate source are given in Section 6. The calculational configuration used to model the installation of temperature probes and the resulting predicted dose rates are discussed in Section 7. Finally, comparisons of measured to calculated dose rates within a drywell are summarized in Section 8. Extended discussions of calculational models and Monte Carlo optimization techniques used are included in Appendix A

  13. PENGEMBANGAN MODEL KOOPERATIF MODELING THE WAY DENGAN TEKNIK RENDRA DALAM PEMBELAJARAN BERMAIN DRAMA BERMUATAN PENDIDIKAN KARAKTER PADA PESERTA DIDIK SMP KELAS VIII

    Directory of Open Access Journals (Sweden)

    Andhi Nugeraha Setiaji

    2014-08-01

    Full Text Available Pembelajaran drama di SMP masih berlangsung kurang maksimal. Model pembelajaran drama yang digunakan juga masih sangat terbatas. Salah satu alternatif model pembelajaran yang bisa digunakan adalah model kooperatif Modeling the Way. Rumusan masalah penelitian ini adalah bagaimana: kebutuhan pengembangan, prinsip pengembangan, prototipe, dan keefektifan model Modeling the Way . Tujuan penelitian ini adalah mengidentifikasi kebutuhan pengembangan, merumuskan prinsip pengembangan, mengembangkan prototipe, dan mengidentifikasi keefektifan model Modeling the Way. Penelitian ini dilakukan dengan desain penelitian R&D. Langkah penelitian ini adalah studi literatur, analisis kebutuhan pengembangan, pengembangan model, uji validasi, revisi, penerapan, revisi, pengembangan model akhir. Teknik pengumpulan data dilaksanakan melalui angket, jurnal, lembar pengamatan, lembar uji validasi, dan teknik tes. Instrumen yang digunakan adalah angket analisis kebutuhan pengembangan, lembar uji validasi, observasi, motivasi,  dan kreativitas peserta didik, serta lembar tes. Teknik analisis data yang digunakan adalah teknik analisis data kebutuhan, uji validasi ahli, dan teknik analisis data uji coba terbatas Hasil penelitian ini adalah sebagai berikut. Kebutuhan pengembangan model Modeling the Way adalah diskusi, guru mengaitkan materi sebelumnya dengan materi yang  dipelajari, dan peserta didik memberikan evaluasi terhadap temannya. Prinsi model ini adalah kerja sama,  kreativitas individu, dan naskah drama bermuatan pendidikan karakter. During this learning in junior high drama still going on less than the maximum. Learners must find their own practice and role-play techniques. Examples of dramatic play techniques demonstrated by the teacher is still less than the maximum . In fact, sometimes the teacher does not show an example of dramatic play. Learning model used drama is still very limited. Often learners immediately given the task to find, read, and

  14. Penggunaan Accelerometer dan Magnetometer pada Sistem Real Time Tracking Indoor Position untuk Studi Kasus Pada Gedung Teknik Informatika ITS

    Directory of Open Access Journals (Sweden)

    Dinar Winia Mahandhira

    2017-01-01

    Full Text Available Indoor Positioning System (IPS menggunakan perangkat mobile seperti smartphone masih menjadi permasalahan yang menantang. Seperti GPS yang tidak bekerja secara akurat di dalam gedung, IPS juga memiliki kelemahan yaitu sangat bergantung pada infrastruktur gedung seperti sinyal WiFi yang terkadang tidak tersebar secara merata di seluruh bagian gedung, sehingga membuat sistem ini terkadang tidak dapat bekerja secara optimal dan real time di setiap bagian gedung. Untuk itulah dikembangkan IPS yang menggunakan sensor gerak seperti accelerometer dan magnetometer sebagai tambahan untuk melakukan update posisi secara real time dengan mendeteksi langkah dan arah hadap pengguna saat berjalan. Pertama, posisi awal pengguna harus ditentukan terlebih dahulu misalnya menggunakan sinyal WiFi yang diproses melalui klasifikasi. Setelah posisi pengguna telah ditentukan, sistem akan mendeteksi pergerakan pengguna secara real time menggunakan sensor gerak. Uji coba dilakukan menggunakan studi kasus gedung Teknik Informatika lantai tiga. Hasil yang diberikan pada saat pengujian memberikan performa yang cukup baik dengan rata-rata persentase akurasi untuk pendeteksian langkah dan estimasi arah hadap pengguna adalah sebesar 94,8% dan 94,48%.

  15. Bahagia dalam Meraih Cita-cita: Kesejahteraan Subjektif Mahasiswa Teknik Arsitektur Ditinjau dari Regulasi Emosi dan Efikasi Diri

    Directory of Open Access Journals (Sweden)

    Setyani Alfinuha

    2017-10-01

    Abstrak: Subjective well-being merupakan evaluasi individu terhadap kehidupannya yang meliputi penilaian kognitif dan afeksi. Individu dikatakan memiliki subjective well-being tinggi jika mengalami lebih banyak afeksi positif atau perasaan menyenangkan dan puas atas kehidupan yang dimiliki. Sebaliknya, orang yang memiliki subjective well-being rendah cenderung diliputi perasaan-perasaan negatif dalam dirinya. Oleh sebab itu, subjective well-being sangat penting dalam kehidupan setiap individu tidak terkecuali pada mahasiswa baru. Ada banyak faktor yang mempengaruhi subjective well-being antara lain jenis kelamin, religiusitas, pendidikan, kecerdasan, regulasi emosi dan self efficacy. Penelitian ini mem­focus­kan tentang pengaruh efikasi diri dan regulasi emosi terhadap subjective well-being. Penelitian ini melibatkan 107 orang mahasiswa baru jurusan teknik arsitektur yang terdiri dari 51 orang laki-laki dan 56 orang perempuan Penelitian ini menggunakan pendekatan kuantitatif yang diukur menggunakan empat skala yaitu Possitive and Negative Affect Schedule (PANAS, Satisfaction with Life Scale (SWLS, General Self efficacy (GSE dan Emotion Regulation Questionnaire (ERQ. Analisis yang dilakukan adalah analisis deskripsi dan regresi linier berganda. Hasil penelitian menunjukkan bahwa terdapat pengaruh self efficacy dan regulasi emosi terhadap subjective well-being. Secara bersama-sama, self efficacy dan regulasi emosi mempengaruhi subjective well-being sebesar 32,5%terhadap subjective well-being. Secara terpisah, self efficacy memberikan sumbangan sebanyak 21,62% dan regulasi emosi sebanyak 3,53% terhadap subjective well-being.

  16. APLIKASI CHATBOT “MI3” UNTUK INFORMASI JURUSAN TEKNIK INFORMATIKA BERBASIS SISTEM PAKAR MENGGUNAKAN METODE FORWARD CHAINING

    Directory of Open Access Journals (Sweden)

    Zifora Nur Baiti

    2013-10-01

    Full Text Available Chatbot adalah suatu aplikasi yang dirancang untuk berkomunikasi dengan mesin. Komunikasi ini membantu user dalam mencari sebuah informasi. Informasi yang diberikan bermacam-macam, seperti tentang akademik. Chatbot yang dibangun ini dikhususkan untuk sebuah informasi yang melingkupi jurusan Teknik Informatika UIN Maliki Malang. Chatbot ini dibangun dengan menerapkan sistem pakar menggunakan metode forward chianing. Metode forward chaining adalah metode yang digunakan untuk mencari kesimpulan dari fakta-fakta  yang  terkumpul.  Metode  forward  chaining  merupakan  algoritma  yang  baik sebagai penyelesaian proses pencarian jawaban berdasarkan kata kunci dari pertanyaan user. Sistem kerja aplikasi ini adalah dengan memecah susunan kalimat menjadi kata kemudian dari kata tersebut oleh sistem akan dicari kunci yang membuat aplikasi dapat menjawab dengan benar. Dari hasil penelitian dengan menginputkan kalimat-kalimat yang berhubungan dan tidak dengan kategori, aplikasi ini mampu mengenali kata kunci pada kalimat-kalimat tersebut. Hal ini mengacu pada hasil pengujian yang didapatkan persentase sebesar  Sangat  Setuju  48,88%  dan  Setuju  51,22%  dari  25  responden  dengan  beberapa kalimat masukan.

  17. Influence of cerium on passivity behavior of wrought AZ91 alloy

    International Nuclear Information System (INIS)

    Wang Henan; Li Ying; Wang Fuhui

    2008-01-01

    In this paper, more focus had been put on the passivity behavior of wrought AZ91 alloy with 1.5 mass% Ce. The passive current density of wrought AZ91 alloy increased with addition of Ce and the passive film became unstable. Structures and compositions of the passive films formed on wrought AZ91 alloy without and with Ce in 0.01 M NaOH aqueous solution were analyzed by potentiostatic polarization, potentiostatic-galvanostatic (P-G) transient technique and X-ray photoelectron spectroscopy (XPS). The results showed that Ce only accumulated in the inner layer of passive film in the form of CeO 2 . Further analysis revealed that there were two main effects of Ce on the passive process of wrought AZ91 alloy: first, the existence of CeO 2 in inner layer of passive film made mass transport through the passive film follow tangent hyperbolic (T) impedance instead of Warburg impedance (W); second, donor concentration (N d ) of the passive film increased by a factor 10 when 1.5 mass% Ce existed in wrought AZ91 alloy, which led to the higher passivity current density

  18. Korozní odolnost tvářených hořčíkových slitin AZ31 a AZ61 v Hankovì roztoku

    Czech Academy of Sciences Publication Activity Database

    Tkacz, J.; Slouková, K.; Minda, J.; Drábiková, J.; Fintová, Stanislava; Doležal, P.; Wasserbauer, J.

    2016-01-01

    Roč. 60, č. 4 (2016), s. 101-106 ISSN 1804-1213 Institutional support: RVO:68081723 Keywords : corrosion * AZ31 magnesium alloy * AZ61 magnesium alloy Subject RIV: JK - Corrosion ; Surface Treatment of Materials https://www.degruyter.com/view/j/kom.2016.60.issue-4/kom-2016-0016/kom-2016-0016.xml?format=INT

  19. Microstructures of friction welded joints of AZ31 to AM60 magnesium alloys

    Energy Technology Data Exchange (ETDEWEB)

    Fukumoto, S.; Ono, T.; Tanaka, S.; Tsubakino, H. [Graduate School of Engineering, Himeji Inst. of Tech., Hyogo (Japan); Tomita, T.; Aritoshi, M. [Hyogo Prefectural Inst. of Industrial Research, Kobe, Hyogo (Japan); Okita, K. [Inst. of Industrial Research, Osaka Sangyo Univ., Osaka (Japan)

    2003-07-01

    AZ31 magnesium alloy was friction-welded to AM60 and the microstructures and the friction welding process were studied. The microstructures changed near the weld interface. The AZ31 was refined to a grain size of several {mu}m near the weld interface. The nucleation occurred in the shear bands that were introduced during the welding process. On the other hand, the eutectic structure was deformed and the lamellar structure which was composed of {alpha}-Mg and Mg{sub 17}Al{sub 12} was formed near the weld interface in AM60 alloy. In the friction process, the adhesion and peel off occurred alternately between AZ31 and AM60. Eventually, bonding was completed during upset process. (orig.)

  20. Diffusion Bonding and Post-Weld Heat Treatment of Extruded AZ91 Magnesium Alloys

    Directory of Open Access Journals (Sweden)

    Fei LIN

    2015-11-01

    Full Text Available The grain size of as-extruded AZ91 magnesium alloys was refined to 12.31 μm from 21.41 μm by recrystallization annealing. The vacuum diffusion welding of as-annealed AZ91 magnesium alloys was researched. The results showed that the maximum shear strength of joints reached 64.70 MPa in the situation of 10 MPa bonding pressure, 18 Pa vacuum degree, 470 °C bonding temperature and 90 min bonding time; both bonding temperature and time are the main influence factors on as-extruded AZ91 magnesium alloys diffusion welding. Then the diffusion welded specimens were annealed, and the shear strength of joints was further improved to 76.93 MPa.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9699

  1. Influence of inorganic acid pickling on the corrosion resistance of magnesium alloy AZ31 sheet

    DEFF Research Database (Denmark)

    Nwaogu, Ugochukwu Chibuzoh; Blawert, C.; Scharnagl, N.

    2009-01-01

    Surface contaminants as a result of thermo-mechanical processing of magnesium alloys, e.g. sheet rolling, can have a negative effect on the corrosion resistance of magnesium alloys. Especially contaminants such as Fe, Ni and Cu, left on the surface of magnesium alloys result in the formation...... of micro-galvanic couples and can therefore increase corrosion attack on these alloys. Due to this influence they should be removed to obtain good corrosion resistance. In this study, the effect of inorganic acid pickling on the corrosion behaviour of a commercial AZ31 magnesium alloy sheet...... cleaning the AZ31 sheet. However, to obtain reasonable corrosion resistance at least 5 mu m of the surface of AZ31 magnesium alloy sheet have to be removed....

  2. Biodegradable behaviors of AZ31 magnesium alloy in simulated body fluid

    International Nuclear Information System (INIS)

    Song Yingwei; Shan Dayong; Chen Rongshi; Zhang Fan; Han Enhou

    2009-01-01

    Magnesium alloys have unique advantages to act as biodegradable implants for clinical application. The biodegradable behaviors of AZ31 in simulated body fluid (SBF) for various immersion time intervals were investigated by electrochemical impedance spectroscopy (EIS) tests and scanning electron microscope (SEM) observation, and then the biodegradable mechanisms were discussed. It was found that a protective film layer was formed on the surface of AZ31 in SBF. With increasing of immersion time, the film layer became more compact. If the immersion time was more than 24 h, the film layer began to degenerate and emerge corrosion pits. In the meantime, there was hydroxyapatite particles deposited on the film layer. The hydroxyapatite is the essential component of human bone, which indicates the perfect biocompatibility of AZ31 magnesium alloy.

  3. Tank 241-AZ-102 Privatization Push Mode Core Sampling and Analysis Plan; FINAL

    International Nuclear Information System (INIS)

    TEMPLETON, A.M.

    1999-01-01

    This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for samples obtained from tank 241-AZ-102. The purpose of this sampling event is to obtain information about the characteristics of the contents of 241-AZ-102. Push mode core samples will be obtained from risers 15C and 24A to provide sufficient material for the chemical analyses and tests required to satisfy these data quality objectives. The 222-S Laboratory will extrude core samples, composite the liquids and solids, perform chemical analyses, and provide subsamples to the Process Chemistry Laboratory. The Process Chemistry Laboratory will prepare test plans and perform process tests to evaluate the behavior of the 241-AZ-102 waste undergoing the retrieval and treatment scenarios defined in the applicable DQOs. Requirements for analyses of samples originating in the process tests will be documented in the corresponding test plan

  4. Tank 241-AZ-101 Mixer Pump Test Vapor Sampling and Analysis Plan

    International Nuclear Information System (INIS)

    TEMPLETON, A.M.

    2000-01-01

    This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for vapor samples obtained during the operation of mixer pumps in tank 241-AZ-101. The primary purpose of the mixer pump test (MPT) is to demonstrate that the two 300 horsepower mixer pumps installed in tank 241-AZ-101 can mobilize the settled sludge so that it can be retrieved for treatment and vitrification. Sampling will be performed in accordance with Tank 241-AZ-101 Mixer Pump Test Data Quality Objective (Banning 1999) and Data Quality Objectives for Regulatory Requirements for Hazardous and Radioactive Air Emissions Sampling and Analysis (Mulkey 1999). The sampling will verify if current air emission estimates used in the permit application are correct and provide information for future air permit applications

  5. Influence of The Arrangement of Materials and Microstructural Analysis During FSW of AZ80A

    Directory of Open Access Journals (Sweden)

    Sevvel P.

    2017-09-01

    Full Text Available The main objective of this paper is to produce defect free weldments with improved properties during friction stir welding of dissimilar Mg alloys. The influence of the anisotropic arrangement of materials when AZ80A Mg alloy is taken as advancing side and AZ91C Mg alloy as retreating side and vice versa with respect to their mechanical properties and microstructural characteristics were investigated. The effects of various FSW parameters on the quality of these joints were also analyzed and best optimized FSW parameters were suggested. Defect free sound joints with excellent mechanical properties were produced when AZ80A Mg alloy was positioned at retreating side. At the same time, it seems a little bit difficult to obtain good quality joints with the contrary arrangement of materials. These investigations revealed that materials having inferior plastic deformability must be kept at the advancing side to obtain sound joints during FSW of dissimilar alloys of Magnesium.

  6. Corrosion behaviour and in vitro/in vivo biocompatibility of surface-modified AZ31 alloy; Comportamiento frente a la corrosion y biocompatibilidad in vitrolin vivo de la aleacion AZ31 modificada superficialmente

    Energy Technology Data Exchange (ETDEWEB)

    Carboneras, M.; Iglesias, C.; Perez-Maceda, B. T.; Valle, J. A. de; Garcia-Alonso, M. C.; Alobera, M. A.; Clemente, C.; Rubio, J. C.; Escudero, M. I.; Lozano, R. M.

    2011-07-01

    The present work evaluates the corrosion behaviour and the in vitro/in vivo biocompatibility of the AZ31 magnesium alloy, which fulfills the mechanical requirements of bone. The corrosion kinetic of as-received AZ31 alloy was not compatible with the cell growth. To improve its performance, the AZ31 alloy was surface modified by a chemical conversion treatment in hydrofluoric acid. The magnesium fluoride layer generated by the surface treatment of AZ31 alloy enhances its corrosion behaviour, allowing the in vitro growth of osteoblastic cells over the surface and the in vivo formation of a highly compact layer of new bone tissue. These results lead to consider the magnesium fluoride coating as necessary for potential use of the AZ31 alloy as biodegradable and absorbable implant for bone repair. (Author) 18 refs.

  7. Microstructure and corrosion behavior of electrodeposited nano-crystalline nickel coating on AZ91 Mg alloy

    Energy Technology Data Exchange (ETDEWEB)

    Zarebidaki, Arman, E-mail: arman.zare@iauyazd.ac.ir; Mahmoudikohani, Hassan, E-mail: hassanmahmoudi.k@gmail.com; Aboutalebi, Mohammad-Reza

    2014-12-05

    Highlights: • Activation, zincating, and Cu electrodeposition were used as pretreatment processes for electrodeposition of nickel coatings. • Nano-crystalline nickel coatings were successfully electrodeposited onto the AZ91 Mg alloys. • Effect of nickel electrodeposited coating on the corrosion resistance of AZ91 Mg alloy has been studied. - Abstract: In order to enhance the corrosion resistance, nickel coating was electrodeposited onto AZ91 Mg alloy. Activation, zincating, and Cu electrodeposition used as pretreatment processes for better adhesion and corrosion performance of the nickel over layer. The corrosion properties of the AZ91 Mg alloy, nickel electroplated AZ91 Mg alloy, and pure nickel was assessed via polarization and electrochemical impedance spectroscopy (EIS) methods in 3.5 wt% NaCl solution. Moreover, the structure of the coating was investigated by means of X-ray diffraction, whereas specimen’s morphology and elemental composition were analyzed using scanning electron microscope (SEM) equipped with energy dispersive spectrometer (EDS). Measurements revealed that the coating has a nano-crystalline structure with the grain size of 95 nm. Corrosion results showed superior corrosion resistance for the coated AZ91 Mg alloy as the corrosion current density decreased from 2.5 × 10{sup −4} A cm{sup −2}, for the uncoated sample, to 1.5 × 10{sup −5} A cm{sup −2}, for coated specimen and the corrosion potential increased from −1.55 V to −0.98 V (vs. Ag/AgCl) at the same condition.

  8. Corrosion and mechanical performance of AZ91 exposed to simulated inflammatory conditions.

    Science.gov (United States)

    Brooks, Emily K; Der, Stephanie; Ehrensberger, Mark T

    2016-03-01

    Magnesium (Mg) and its alloys, including Mg-9%Al-1%Zn (AZ91), are biodegradable metals with potential use as temporary orthopedic implants. Invasive orthopedic procedures can provoke an inflammatory response that produces hydrogen peroxide (H2O2) and an acidic environment near the implant. This study assessed the influence of inflammation on both the corrosion and mechanical properties of AZ91. The AZ91 samples in the inflammatory protocol were immersed for three days in a complex biologically relevant electrolyte (AMEM culture media) that contained serum proteins (FBS), 150 mM of H2O2, and was titrated to a pH of 5. The control protocol immersed AZ91 samples in the same biologically relevant electrolyte (AMEM & FBS) but without H2O2 and the acid titration. After 3 days all samples were switched into fresh AMEM & FBS for an additional 3-day immersion. During the initial immersion, inflammatory protocol samples showed increased corrosion rate determined by mass loss testing, increased Mg and Al ion released to solution, and a completely corroded surface morphology as compared to the control protocol. Although corrosion in both protocols slowed once the test electrolyte solution was replaced at 3 days, the samples originally exposed to the simulated inflammatory conditions continued to display enhanced corrosion rates as compared to the control protocol. These lingering effects may indicate the initial inflammatory corrosion processes modified components of the surface oxide and corrosion film or initiated aggressive localized processes that subsequently left the interface more vulnerable to continued enhanced corrosion. The electrochemical properties of the interfaces were also evaluated by EIS, which found that the corrosion characteristics of the AZ91 samples were potentially influenced by the role of intermediate adsorption layer processes. The increased corrosion observed for the inflammatory protocol did not affect the flexural mechanical properties of the AZ91

  9. Blocking spinal CCR2 with AZ889 reversed hyperalgesia in a model of neuropathic pain

    Directory of Open Access Journals (Sweden)

    Vaillancourt François

    2010-12-01

    Full Text Available Abstract Background The CCR2/CCL2 system has been identified as a regulator in the pathogenesis of neuropathy-induced pain. However, CCR2 target validation in analgesia and the mechanism underlying antinociception produced by CCR2 antagonists remains poorly understood. In this study, in vitro and in vivo pharmacological approaches using a novel CCR2 antagonist, AZ889, strengthened the hypothesis of a CCR2 contribution to neuropathic pain and provided confidence over the possibilities to treat neuropathic pain with CCR2 antagonists. Results We provided evidence that dorsal root ganglia (DRG cells harvested from CCI animals responded to stimulation by CCL2 with a concentration-dependent calcium rise involving PLC-dependent internal stores. This response was associated with an increase in evoked neuronal action potentials suggesting these cells were sensitive to CCR2 signalling. Importantly, treatment with AZ889 abolished CCL2-evoked excitation confirming that this activity is CCR2-mediated. Neuronal and non-neuronal cells in the spinal cord were also excited by CCL2 applications indicating an important role of spinal CCR2 in neuropathic pain. We next showed that in vivo spinal intrathecal injection of AZ889 produced dose-dependent analgesia in CCI rats. Additionally, application of AZ889 to the exposed spinal cord inhibited evoked neuronal activity and confirmed that CCR2-mediated analgesia involved predominantly the spinal cord. Furthermore, AZ889 abolished NMDA-dependent wind-up of spinal withdrawal reflex pathway in neuropathic animals giving insight into the spinal mechanism underlying the analgesic properties of AZ889. Conclusions Overall, this study strengthens the important role of CCR2 in neuropathic pain and highlights feasibility that interfering on this mechanism at the spinal level with a selective antagonist can provide new analgesia opportunities.

  10. Electrochemical polymerization of pyrrole over AZ31 Mg alloy for biomedical applications

    International Nuclear Information System (INIS)

    Srinivasan, A.; Ranjani, P.; Rajendran, N.

    2013-01-01

    Highlights: ► Polymerization of pyrrole over AZ31 Mg was carried out using cyclic voltammetry. ► Pyrrole concentration was optimized to accomplish the adherent and uniform coating. ► Effect of monomer concentration on the surface morphology was discussed. ► Corrosion resistance of AZ31 Mg in SBF was studied as a function of Py concentration. ► PPy coated AZ31 Mg alloy exhibited enhanced corrosion resistance at 0.25 M of Py. -- Abstract: Electrochemical polymerization of pyrrole (Py) from aqueous salicylate solution over AZ31 Mg alloy was carried out using cyclic voltammetry (CV). The effect of monomer concentration on the surface and electrochemical corrosion in simulated body fluid (SBF) were analysed. Attenuated total reflection-infrared (ATR-IR) spectra showed the characteristic ring stretching peaks for polypyrrole (PPy). Scanning electron microscopy (SEM) and atomic force microscopy (AFM) studies exhibited typical cauliflower morphology with rough surface for PPy coated AZ31 Mg alloy. Open circuit potential measurement and potentiodynamic polarization studies revealed that the coating prepared using 0.25 M of Py had positive shift of about 120 mV in corrosion potential and lower corrosion current density (0.03 mA/cm 2 ) compared to other concentrations and uncoated AZ31 Mg alloy (0.25 mA/cm 2 ). Electrochemical impedance spectroscopic (EIS) studies of uncoated and PPy coated Mg alloy in SBF revealed three-time constants behaviour with about one order of increment in impedance value for 0.25 M of Py

  11. Assessing the ecosystem service potential of Tucson AZ's urban forest

    Science.gov (United States)

    Pavao-Zuckerman, M.

    2011-12-01

    Urbanization is arguably one of the most dramatic forms of landscape change, and an important anthropogenic influence on the structure and function of ecosystems. Cities have obvious impacts on local ecologies and environments, such as shifts in species diversity and alteration of local microclimates. While scientists are now familiar with many of these localized impacts of urbanization, cities and suburban areas contribute to 10-15 % of surface land cover in the conterminous U.S., pointing to the potential, yet poorly understood, contribution of cities to regional, national, and global carbon (C) and energy budgets. As cities continue to expand urban ecologists place more emphasis on understanding the functions of urban ecosystems and the ecosystem services (e.g. habitat, air, and water quality) that cities provide. While studies demonstrate that the urban environment alters the structure and function of remnant patches of native ecosystems relative to their non-urban counterparts, the ability of restoration, planning, and design to improve the provision of ecosystem services is a new approach within ecology. One strategy involves green urban design, or using ecological principles for planning or reinvigorating certain ecological processes, in cities. Increasing the amount of vegetative cover can reduce this effect by reinforcing ecosystem services in cities, including shading of surfaces, promotion of cooling through evapotranspiration, and the sequestration of atmospheric CO2 in plant tissues and soils. However, the on-the-ground reality of such strategies is relatively unknown. A pilot study is being conducted in Tucson, AZ to investigate the impact of increasing the cover of trees in the urban landscape on local microclimates and the urban heat island. Trees (Velvet Mesquite, Chilean Mesquite, and Desert Willow) were planted in two neighborhoods in Tucson in 1990. We are collecting data during the summer 2011 monsoon (DBH, crown volume, and hemispherical

  12. 78 FR 34403 - Notice of Availability of the Record of Decision for the Quartzsite Solar Energy Project, AZ

    Science.gov (United States)

    2013-06-07

    ...; AZA34666] Notice of Availability of the Record of Decision for the Quartzsite Solar Energy Project, AZ... Solar Energy Project (QSEP). The Acting Assistant Secretary for Land and Minerals Management approved...: http://www.blm.gov/az/st/en/prog/energy/solar/quartzsite_solar_energy.html . FOR FURTHER INFORMATION...

  13. Differential deposition of H2A.Z in rice seedling tissue during the day-night cycle.

    Science.gov (United States)

    Zhang, Kang; Xu, Wenying; Wang, Chunchao; Yi, Xin; Su, Zhen

    2017-03-04

    Chromatin structure has an important role in modulating gene expression. The incorporation of histone variants into the nucleosome leads to important changes in the chromatin structure. The histone variant H2A.Z is highly conserved between different species of fungi, animals, and plants. However, dynamic changes to H2A.Z in rice have not been reported during the day-night cycle. In this study, we generated genome wide maps of H2A.Z for day and night time in harvested seedling tissues by combining chromatin immunoprecipitation and high-throughput sequencing. The analysis results for the H2A.Z data sets detected 7099 genes with higher depositions of H2A.Z in seedling tissues harvested at night compared with seedling tissues harvested during the day, whereas 4597 genes had higher H2A.Z depositions in seedlings harvested during the day. The gene expression profiles data suggested that H2A.Z probably negatively regulated gene expression during the day-night cycle and was involved in many important biologic processes. In general, our results indicated that H2A.Z may play an important role in plant responses to the diurnal oscillation process.

  14. An exponential material model for prediction of the flow curves of several AZ series magnesium alloys in tension and compression

    International Nuclear Information System (INIS)

    Fereshteh-Saniee, F.; Barati, F.; Badnava, H.; Fallah Nejad, Kh.

    2012-01-01

    Highlights: ► The exponential model can represent flow behaviors of AZ series Mg alloys very well. ► Strain rate sensitivities of AZ series Mg alloys in compression are nearly the same. ► Effect of zinc element on tensile activation energy is higher than on compressive one. ► Activation energies of AZ80 and AZ81 in tension were greater than in compression. ► Tensile and compressive rate sensitivities of AZ80 are not close to each other. -- Abstract: This paper is concerned with flow behaviors of several magnesium alloys, such as AZ31, AZ80 and AZ81, in tension and compression. The experiments were performed at elevated temperatures and for various strain rates. In order to eliminate the effect of inhomogeneous deformation in tensile and compression tests, the Bridgeman’s and numerical correction factors were respectively employed. A two-section exponential mathematical model was also utilized for prediction of flow stresses of different magnesium alloys in tension and compression. Moreover, based on the compressive flow model proposed, the peak stress and the relevant true strain could be estimated. The true stress and strain of the necking point can also be predicted using the corresponding relations. It was found that the flow behaviors estimated by the exponential flow model were encouragingly in very good agreement with experimental findings.

  15. Qualitative Research of AZ31 Magnesium Alloy Aircraft Brackets Produced by a New Forging Method

    Directory of Open Access Journals (Sweden)

    Dziubińska A.

    2016-06-01

    Full Text Available The paper reports a selection of numerical and experimental results of a new closed-die forging method for producing AZ31 magnesium alloy aircraft brackets with one rib. The numerical modelling of the new forming process was performed by the finite element method.The distributions of stresses, strains, temperature and forces were examined. The numerical results confirmed that the forgings produced by the new forming method are correct. For this reason, the new forming process was verified experimentally. The experimental results showed good agreement with the numerical results. The produced forgings of AZ31 magnesium alloy aircraft brackets with one rib were then subjected to qualitative tests.

  16. Influence of Zeolite Coating on the Corrosion Resistance of AZ91D Magnesium Alloy.

    Science.gov (United States)

    Banerjee, P Chakraborty; Woo, Ren Ping; Grayson, Sam Matthew; Majumder, Amrita; Raman, R K Singh

    2014-08-22

    The protective performance of zeolite coating on AZ91D magnesium alloy was evaluated using potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS) in 0.1 M sodium chloride solution (NaCl). Electrical equivalent circuit (EEC) was developed based upon hypothetical corrosion mechanisms and simulated to correspond to the experimental data. The morphology and the chemical nature of the coating were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Post corrosion morphologies of the zeolite coated and the uncoated AZ91D alloy were investigated using SEM. The corrosion resistance of the zeolite coated specimen was at least one order of magnitude higher than the uncoated specimen.

  17. Augmenting the Energy-Saving Impact of IEEE 802.3az via the Control Plane

    OpenAIRE

    Thaenchaikun , Chakadkit; Jakllari , Gentian; Paillassa , Béatrice

    2015-01-01

    International audience; IEEE 802.3az, the recent standard for Energy Efficient Ethernet, is one of the main contributions of the ICT industry to the global quest for energy efficiency. Energy consumption reduction is accomplished by essentially replacing the continuous IDLE of legacy IEEE 802.3 cards with a Low Power Idle. While this is an important step in the right direction, studies have shown that the energy saving with IEEE 802.3az highly depends on the traffic load and stops for link ut...

  18. Anticorrosive magnesium hydroxide coating on AZ31 magnesium alloy by hydrothermal method

    International Nuclear Information System (INIS)

    Zhu Yanying; Wu Guangming; Xing Guangjian; Li Donglin; Zhao Qing; Zhang Yunhong

    2009-01-01

    Magnesium alloys are potential biodegradable biomaterials in orthopedic surgery. However, the rapid degradation rate has limited their application in biomedical field. A great deal of studies have been done to improve the resistance of magnesium alloys. In this article, An anticorrosive magnesium hydroxide coating with a thickness of approximately 100μm was formed on an AZ31 magnesium alloy by hydrothermal method. The morphology of the coatings were observed by an optical microscope and SEM. And the samples were soaked in hank's solution (37 deg. C) to investigate the corrosion resistance. Magnesium alloy AZ31 with magnesium hydroxide coatings present superior corrosion resistance than untreated samples.

  19. Effects of organic acid pickling on the corrosion resistance of magnesium alloy AZ31 sheet

    DEFF Research Database (Denmark)

    Nwaogu, Ugochukwu Chibuzoh; Blawert, C.; Scharnagl, N.

    2010-01-01

    mu m of the contaminated surface was required to reach corrosion rates less than 1 mm/year in salt spray condition. Among the three organic acids examined, acetic acid is the best choice. Oxalic acid can be an alternative while citric acid is not suitable for cleaning AZ31 sheet, because......Organic acids were used to clean AZ31 magnesium alloy sheet and the effect of the cleaning processes on the surface condition and corrosion performance of the alloy was investigated. Organic acid cleanings reduced the surface impurities and enhanced the corrosion resistance. Removal of at least 4...

  20. Structure of the AZ91 alloy pressure castings fabricated of home scrap containing charge

    Directory of Open Access Journals (Sweden)

    Z. Konopka

    2011-04-01

    Full Text Available The influence of the AZ91 alloy home scrap addition to the metal charge on both the structure and the selected mechanical propertiesof pressure castings was examined in this article. Two heats were made using different components, the first with only pure AZ91 alloyingots in the charge, and the second containing 30 wt % of home scrap. The hot chamber 3 MN machine was used for casting. Thestructures of the castings and their Brinell hardness were examined for both cases. A strong refinement of crystals was observed in castings made with the contribution of the recycled material. Any significant differences in castings hardness were not observed.

  1. Acceptance Test Report for the 241-AZ-101 Ultrasonic Interface Level Analyzer

    Energy Technology Data Exchange (ETDEWEB)

    ANDREWS, J.E.

    2000-01-27

    This document comprises the Acceptance Test Report for the 241-AZ-101 Ultrasonic Interface Level Analyzer. This document presents the results of Acceptance Testing of the 241-AZ-101 Ultrasonic Interface Level Analyzers (URSILLAs). Testing of the URSILLAs was performed in accordance with ATP-260-001, ''URSILLA Pre-installation Acceptance Test Procedure''. The objective of the testing was to verify that all equipment and components function in accordance with design specifications and original equipment manufacturer's specifications.

  2. Patrón de consumo e ingestas recomendadas de azúcar

    OpenAIRE

    Joan Quiles i Izquierdo

    2013-01-01

    Los azúcares son hidratos de carbono con sabor dulce que proveen energía al organismo. El cerebro adulto utiliza aproximadamente 140 g de glucosa al día, cantidad que puede representar hasta el 50% del total de hidratos de carbono que se consumen. En nuestro país el patrón de consumo de azúcar en alimentos permanece constante, mientras que el consumo de bebidas refrescantes presenta un aumento en los últimos cuatro años. La Encuesta Nacional de Ingesta Dietética de España (ENIDE, 2010-11) est...

  3. APLIKASI TEKNIK AAN DI REAKTOR RSG-GAS PADA PENENTUAN UNSUR ESENSIAL DAN TOKSIK DI DALAM IKAN DAN PAKAN IKAN

    Directory of Open Access Journals (Sweden)

    Saeful Yusuf

    2015-03-01

    Full Text Available Pada makalah ini diuraikan tentang aplikasi teknik AAN (Analisis Aktivasi Neutron dalam penentuan konsentrasi unsur-unsur esensial dan cemaran yang terkandung di dalam beberapa spesies ikan dan pakan ikan. Unsur-unsur esensial yang terkandung dalam pakan ikan buatan juga dianalisis untuk mengetahui pengaruhnya terhadap ikan. Penentuan unsur menggunakan teknik AAN dengan metode perbandingan dan metode k0-AAN. Sampel diiradiasi di reaktor RSG-GAS yang memiliki fluks neutron thermal 5 x 1013 n.cm-2.s-1 pada daya 15 MW. Hasil penelitian menunjukkan bahwa 12 unsur di dalam 11 spesies ikan air laut dan air tawar telah ditentukan yaitu As, Br, Cr, Co, Cs, Fe, Hg, K, Na, Rb, Se and Zn. Konsentrasi cemaran As didalam ikan laut sudah melampaui batas maksimum 1 mg/kg, sedangkan konsentrasi cemaran Hg masih dibawah batas maksimum 0,5 mg/kg, baik untuk ikan laut maupun ikan air tawar. Unsur K dan Na merupakan unsur makroesensial sedangkan unsur Cr, Co, Fe, Se and Zn adalah termasuk unsur mikroesensial. Secara umum ditunjukkan bahwa kandungan mineral didalam ikan laut lebih tinggi konsentrasinya dibandingkan ikan air tawar. Br, Cs dan Rb merupakan unsur-unsur non esensial yang teridentifikasi dalam semua ikan yang dianalisis. Penelitian terhadap pakan ikan air tawar menunjukkan bahwa semua unsur yang teridentifikasi juga terdapat di dalam ikan laut dan ikan air tawar. Hal ini menunjukkan bahwa pakan ikan berkontribusi terhadap konsentrasi unsur di dalam ikan air tawar. Kata kunci : Analisis aktivasi neutron, unsur esensial, unsur cemaran, ikan, pakan ikan   This paper reported on the application of NAA (Neutron Activation Analysis Technique in the determination of the concentration of the essential and toxic elements in some species of fish and fish feed. Determination of elements using instrumental NAA technique with comparison and k0-INAA methods. Samples were irradiated in the RSG-GAS which has a thermal neutron flux  5.0E +13 ncm-2s-1. The results

  4. Comportamiento mecánico de la aleación AZ31 reforzada con nanofibras de carbono

    Directory of Open Access Journals (Sweden)

    Adeva, P.

    2010-12-01

    Full Text Available The aim of this study is to investigate the effect of reinforcing AZ31 with carbon nanofibres. The materials AZ31, AZ31-1 % C y AZ31-2 % C were produced by a conventional powder metallurgy route consisting of mechanical mixing of nanofibres and powders of AZ31, cool compactation and extrusion at 350 °C. After extrusion the three materials exhibited a recrystallized microstructure of similar grain size, fine and rather inhomogeneous. Furthermore, they presented a weak fibre texture with basal plane parallel to the extrusion direction. The tensile properties were affected by the nanofibres presence only at 100 °C. At this temperature, yield strength and tensile strength were 30% higher than in the unreinforced alloy.

    En este trabajo se ha estudiado el efecto de la adición de nanofibras de carbono en las propiedades mecánicas de la aleación AZ31 procesada por una ruta pulvimetalúrgica convencional. Se prepararon tres materiales, AZ31, AZ31- 1 % C y AZ31-2 % C. Tras una mezcla mecánica de las nanofibras con los polvos de AZ31, se precompactaron en frío y se extruyeron a 350 °C. Los tres presentan una microestructura recristalizada con un tamaño de grano similar, fino aunque algo heterogéneo. Los tres materiales presentan una débil textura de fibra con el plano basal paralelo a la dirección de extrusión. Las propiedades mecánicas a tracción únicamente se ven afectadas por la presencia de nanofibras a 100 °C superando los materiales reforzados en un 30 % a los valores de límite elástico y resistencia de la aleación sin reforzar.

  5. Cesium Removal From Tanks 241-AN-103 and 241-SX-105 and 241-AZ-101 and 241-AZ-102 Composite For Testing In Bench Scale Steam Reformer

    International Nuclear Information System (INIS)

    Duncan, J.B.; Huber, H.J.

    2011-01-01

    This report documents the preparation of three actual Hanford tank waste samples for shipment to the Savannah River National Laboratory (SRNL). Two of the samples were dissolved saltcakes from tank 241-AN-103 (hereafter AN-103) and tank 241-SX-105 (hereafter SX-105); one sample was a supernate composite from tanks 241-AZ-101 and 241-AZ-102 (hereafter AZ-101/102). The preparation of the samples was executed following the test plans LAB-PLAN-10-00006, Test Plan for the Preparation of Samples from Hanford Tanks 241-SX-105, 241-AN-103, 241-AN-107, and LAB-PLN-l0-00014, Test Plan for the Preparation of a Composite Sample from Hanford Tanks 241-AZ-101 and 241-AZ-102 for Steam Reformer Testing at the Savannah River National Laboratory. All procedural steps were recorded in laboratory notebook HNF-N-274 3. Sample breakdown diagrams for AN-103 and SX-105 are presented in Appendix A. The tank samples were prepared in support of a series of treatability studies of the Fluidized Bed Steam Reforming (FBSR) process using a Bench-Scale Reformer (BSR) at SRNL. Tests with simulants have shown that the FBSR mineralized waste form is comparable to low-activity waste glass with respect to environmental durability (WSRC-STI-2008-00268, Mineralization of Radioactive Wastes by Fluidized Bed Steam Reforming (FBSR): Comparisons to Vitreous Waste Forms and Pertinent Durability Testing). However, a rigorous assessment requires long-term performance data from FBSR product formed from actual Hanford tank waste. Washington River Protection Solutions, LLC (WRPS) has initiated a Waste Form Qualification Program (WP-5.2.1-2010-001, Fluidized Bed Steam Reformer Low-level Waste Form Qualification) to gather the data required to demonstrate that an adequate FBSR mineralized waste form can be produced. The documentation of the selection process of the three tank samples has been separately reported in RPP-48824, Sample Selection Process for Bench-Scale Steam Reforming Treatability Studies Using

  6. CESIUM REMOVAL FROM TANKS 241-AN-103 & 241-SX-105 & 241-AZ-101 & 241AZ-102 COMPOSITE FOR TESTING IN BENCH SCALE STEAM REFORMER

    Energy Technology Data Exchange (ETDEWEB)

    DUNCAN JB; HUBER HJ

    2011-04-21

    This report documents the preparation of three actual Hanford tank waste samples for shipment to the Savannah River National Laboratory (SRNL). Two of the samples were dissolved saltcakes from tank 241-AN-103 (hereafter AN-103) and tank 241-SX-105 (hereafter SX-105); one sample was a supernate composite from tanks 241-AZ-101 and 241-AZ-102 (hereafter AZ-101/102). The preparation of the samples was executed following the test plans LAB-PLAN-10-00006, Test Plan for the Preparation of Samples from Hanford Tanks 241-SX-105, 241-AN-103, 241-AN-107, and LAB-PLN-l0-00014, Test Plan for the Preparation of a Composite Sample from Hanford Tanks 241-AZ-101 and 241-AZ-102 for Steam Reformer Testing at the Savannah River National Laboratory. All procedural steps were recorded in laboratory notebook HNF-N-274 3. Sample breakdown diagrams for AN-103 and SX-105 are presented in Appendix A. The tank samples were prepared in support of a series of treatability studies of the Fluidized Bed Steam Reforming (FBSR) process using a Bench-Scale Reformer (BSR) at SRNL. Tests with simulants have shown that the FBSR mineralized waste form is comparable to low-activity waste glass with respect to environmental durability (WSRC-STI-2008-00268, Mineralization of Radioactive Wastes by Fluidized Bed Steam Reforming (FBSR): Comparisons to Vitreous Waste Forms and Pertinent Durability Testing). However, a rigorous assessment requires long-term performance data from FBSR product formed from actual Hanford tank waste. Washington River Protection Solutions, LLC (WRPS) has initiated a Waste Form Qualification Program (WP-5.2.1-2010-001, Fluidized Bed Steam Reformer Low-level Waste Form Qualification) to gather the data required to demonstrate that an adequate FBSR mineralized waste form can be produced. The documentation of the selection process of the three tank samples has been separately reported in RPP-48824, Sample Selection Process for Bench-Scale Steam Reforming Treatability Studies Using

  7. Expression of P. falciparum var Genes Involves Exchange of the Histone Variant H2A.Z at the Promoter

    Science.gov (United States)

    Petter, Michaela; Lee, Chin Chin; Byrne, Timothy J.; Boysen, Katja E.; Volz, Jennifer; Ralph, Stuart A.; Cowman, Alan F.; Brown, Graham V.; Duffy, Michael F.

    2011-01-01

    Plasmodium falciparum employs antigenic variation to evade the human immune response by switching the expression of different variant surface antigens encoded by the var gene family. Epigenetic mechanisms including histone modifications and sub-nuclear compartmentalization contribute to transcriptional regulation in the malaria parasite, in particular to control antigenic variation. Another mechanism of epigenetic control is the exchange of canonical histones with alternative variants to generate functionally specialized chromatin domains. Here we demonstrate that the alternative histone PfH2A.Z is associated with the epigenetic regulation of var genes. In many eukaryotic organisms the histone variant H2A.Z mediates an open chromatin structure at promoters and facilitates diverse levels of regulation, including transcriptional activation. Throughout the asexual, intraerythrocytic lifecycle of P. falciparum we found that the P. falciparum ortholog of H2A.Z (PfH2A.Z) colocalizes with histone modifications that are characteristic of transcriptionally-permissive euchromatin, but not with markers of heterochromatin. Consistent with this finding, antibodies to PfH2A.Z co-precipitate the permissive modification H3K4me3. By chromatin-immunoprecipitation we show that PfH2A.Z is enriched in nucleosomes around the transcription start site (TSS) in both transcriptionally active and silent stage-specific genes. In var genes, however, PfH2A.Z is enriched at the TSS only during active transcription in ring stage parasites. Thus, in contrast to other genes, temporal var gene regulation involves histone variant exchange at promoter nucleosomes. Sir2 histone deacetylases are important for var gene silencing and their yeast ortholog antagonises H2A.Z function in subtelomeric yeast genes. In immature P. falciparum parasites lacking Sir2A or Sir2B high var transcription levels correlate with enrichment of PfH2A.Z at the TSS. As Sir2A knock out parasites mature the var genes are

  8. Perawatan Maloklusi Angle Klas I dengan Gigi Depan Crowding Berat dan Cross Bite Menggunakan Teknik Begg pada Pasien dengan Kebersihan Mulut Buruk

    Directory of Open Access Journals (Sweden)

    Sri Wahyuningsih

    2014-12-01

    Full Text Available Gigi depan crowding/berjejal parah dan cross bite adalah kasus yang sering dijumpai pada perawatan ortodontik. Gigi crowding dapat menyulitkan membersihkan mulut pada area gigi crowding sehingga dapat menyebabkan masalah periodontal. Salah satu keuntungan perawatan ortodontik cekat dengan teknik Begg adalah menghasilkan gaya yang ringan dalam megkoreksi gigi berjejal dan cross bite dapat memberikan kenyamanan pada pasien. Tujuan perawatan ini adalah untuk mengkoreksi gigi berjejal dan cross bite dalam waktu yang singkat menggunakan teknik Begg. Seorang pasien wanita umur 24 tahun dengan maloklusi Angle klas I dan skeletal klas III protrusif mandibula, gigi depan crowding berat dan cross bite, konstraksi lengkung pada kedua rahang, pergeseran median line rahang atas dan bawah disertai, gingivitis berat dan karies. Skaling, perawatan saluran akar dan pencabutan gigi non vital dilakukan sebelum perawatan ortodontik dilakukan. Koreksi dengan teknik Begg memerlukan waktu selama 6 bulan untuk mengkoreksi gigi crowding dan cross bite semuanya dalam waktu yang sama. Koreksi kasus gigi depan crowding berat dan cross bite disertai masalah periodontal dapat dilakukan dengan teknik Begg dalam waktu yang singkat dengan kemajuan yang bagus.   Treatment of Class I Angle Malocclusion with Severe Crowding and Crossbite of Anterior Teeth Using Begg Technique in Bad Oral Hygiene Patient. The severe crowding and cross bite of anterior teeth were very common type cases in orthodontic. Crowding teeth compromised the oral hygiene due to the difficulty in oral cleansing on the crowding area that cause periodontal problem. One of advantages of fixed orthodontic treatment using Begg technique produced the light forces in correcting crowding and cross bite could give convenience to patients. The purpose of this treatment is to correct crowding and cross bite in a short period of time using Begg technique. A 24 years old female patient with Class I Angle

  9. 75 FR 11554 - Notice of Intent to Repatriate Cultural Items: Museum of Northern Arizona, Flagstaff, AZ

    Science.gov (United States)

    2010-03-11

    ... continue to be used by traditional Navajo religious practitioners. Based on the sacred esoteric knowledge... Northern Arizona, Flagstaff, AZ, that meet the definitions of ``sacred objects'' and ``objects of cultural... the area of Farmington, NM. The 29 cultural items are 4 watercolors of sacred Navajo Yei figures and...

  10. 241-AZ-101 Waste Tank Color Video Camera System Shop Acceptance Test Report

    International Nuclear Information System (INIS)

    WERRY, S.M.

    2000-01-01

    This report includes shop acceptance test results. The test was performed prior to installation at tank AZ-101. Both the camera system and camera purge system were originally sought and procured as a part of initial waste retrieval project W-151

  11. Fault-tolerant epoxy-silane coating for corrosion protection of magnesium alloy AZ31

    NARCIS (Netherlands)

    Lamaka, S.V.; Xue, H.B.; Meis, N.N.A.H.; Esteves, A.C.C.; Ferreira, M.G.S.

    2015-01-01

    In this work, a hybrid epoxy-silane coating was developed for corrosion protection of magnesium alloy AZ31. The average thickness of the film produced by dip-coating procedure was 14 µm. The adhesion strength of the epoxy-silane coating to the Mg substrate was evaluated by pull-off tests and was

  12. 241-AZ-101 Waste Tank Color Video Camera System Shop Acceptance Test Report

    Energy Technology Data Exchange (ETDEWEB)

    WERRY, S.M.

    2000-03-23

    This report includes shop acceptance test results. The test was performed prior to installation at tank AZ-101. Both the camera system and camera purge system were originally sought and procured as a part of initial waste retrieval project W-151.

  13. Laser cladding of Zr-based coating on AZ91D magnesium alloy for ...

    Indian Academy of Sciences (India)

    based coating made of Zr powder was fabricated on AZ91D magnesium alloy by laser cladding. The microstructure of the coating was characterized by XRD, SEM and TEM techniques. The wear resistance of the coating was evaluated under dry ...

  14. Flow mechanisms in creep of a short-fibre AZ91 alloy-based composite

    Czech Academy of Sciences Publication Activity Database

    Pahutová, Marie; Sklenička, Václav; Kuchařová, Květa; Svoboda, Milan; Langdon, T. G.

    43 2005, č. 1 (2005), s. 34-44 ISSN 0023-432X R&D Projects: GA ČR(CZ) GA106/03/0901 Institutional research plan: CEZ:AV0Z20410507 Keywords : AZ91 magnesium alloy * metal matrix composite * short fibre reinforcement Subject RIV: JG - Metallurgy Impact factor: 0.973, year: 2005

  15. Study on fused/cast AZS refractories for deployment in vitrification of radioactive waste effluents

    Science.gov (United States)

    Sengupta, Pranesh; Mishra, R. K.; Soudamini, N.; Sen, D.; Mazumder, S.; Kaushik, C. P.; Ajithkumar, T. G.; Banerjee, K.

    2015-12-01

    'Fused/cast Al2O3-ZrO2-SiO2 (FC-AZS)' is being considered as 'glass contact refractory' within ceramic melters, to be used for nuclear waste immobilization. Microstructural analyses reveal random distributions of baddeleyite (ZrO2) within aluminosilicate (Al2SiO5) matrix. 27Al and 29Si NMR data suggest that within aluminosilicate matrix Al occurs in both 4- and 6-fold co-ordinations whereas Si prefers a 4-fold environment. Polydispersity of pores has been studied with small-angle neutron scattering (SANS) technique. Corrosion rates of FC-AZS within 6 M HNO3, simulated wastes (500 h exposure), and borosilicate melt (975 °C, 800 h exposure) are found to be 0.38 × 103 μmy-1, 0.13 × 103 μmy-1 and 4.75 × 103 μmy-1 respectively. A comparison of chemical interaction data clearly suggests that FC-AZS exhibits better chemical durability than AZC refractory (Al2O3-ZrO2-Cr2O3, also used for similar purpose). Thermal cycling studies indicate that FC-AZS retains structural integrity (including compressive strength and density) even up to 20 cycles.

  16. 78 FR 23135 - Safety Zone; Blue Water Resort & Casino West Coast Nationals; Parker, AZ

    Science.gov (United States)

    2013-04-18

    ...-AA00 Safety Zone; Blue Water Resort & Casino West Coast Nationals; Parker, AZ AGENCY: Coast Guard, DHS... Water Resort & Casino West Coast Nationals. This temporary safety zone is necessary to provide for the....). RPM Racing Enterprises is sponsoring the Blue Water Resort & Casino West Coast Nationals, which is...

  17. 75 FR 11939 - DNS Electronics, Chandler, AZ; Notice of Termination of Investigation

    Science.gov (United States)

    2010-03-12

    ... DEPARTMENT OF LABOR Employment and Training Administration [TA-W-70,654] DNS Electronics, Chandler, AZ; Notice of Termination of Investigation Pursuant to Section 223 of the Trade Act of 1974, as... on behalf of workers of DNS Electronics, Chandler, Arizona. The petitioning group of workers is...

  18. Laser cladding of Zr-based coating on AZ91D magnesium alloy for ...

    Indian Academy of Sciences (India)

    3Hubei Key Laboratory of Hydroelectric Machinery Design & Maintenance, ... To improve the wear and corrosion resistance of AZ91D magnesium alloy, Zr-based coating made of ... process that lead to inflammatory cascades which reduce bio- ... tions regarding their application as protective films on load- ... Experimental.

  19. 75 FR 5115 - Temporary Concession Contract for Lake Mead National Recreation Area, AZ/NV

    Science.gov (United States)

    2010-02-01

    ... National Recreation Area, AZ/NV AGENCY: National Park Service, Department of the Interior. ACTION: Notice of intention to award temporary concession contract for Lake Mead National Recreation Area. SUMMARY: Pursuant to 36 CFR 51.24, public notice is hereby given that the National Park Service intends to award a...

  20. Effect of Pr addition on microstructure and mechanical properties of AZ61 magnesium alloy

    Directory of Open Access Journals (Sweden)

    You Zhiyong

    2014-03-01

    Full Text Available To improve the strength, hardness and heat resistance of Mg-6Al-1Zn (AZ61 alloy, the effects of Pr addition on the as-cast microstructure and mechanical properties of AZ61 alloy were investigated at room and elevated temperatures by means of Brinell hardness measurement, optical microscope (OM, scanning electron microscope (SEM, energy dispersive spectroscopy (EDS, X-ray diffractometer (XRD and DNS100 electronic universal testing machine. The results show that the microstructures of Pr-containing AZ61 alloys were refined, with primary β-Mg17Al12 phase distributed homogeneously. When the addition of Pr is up to 1.2wt.%, the β phase becomes finer, and new needle-like or short-rod shaped Al11Pr3 phase and blocky AlPr phase appear. As a result, optimal tensile properties are obtained. However, greater than 1.2wt.% Pr addition leads to poorer mechanical properties due to the aggregation of the needle-like phase and large size of grains. The present research findings provide a new way for strengthening of magnesium alloys at room and elevated temperatures, and a method of producing thermally-stable AZ61 magnesium alloy.

  1. Mechanical properties of plasma-sprayed layers of aluminium and aluminium alloy on AZ 91

    Czech Academy of Sciences Publication Activity Database

    Kubatík, Tomáš František; Ctibor, Pavel; Mušálek, Radek; Janata, Marek

    2017-01-01

    Roč. 51, č. 2 (2017), s. 323-327 ISSN 1580-2949 R&D Projects: GA ČR(CZ) GP14-31538P Institutional support: RVO:61389021 Keywords : plasma spraying of aluminium * adhesion of coating * wear * magnesium alloy AZ91 Subject RIV: JG - Metallurgy OBOR OECD: Materials engineering Impact factor: 0.436, year: 2016

  2. Structural evaluation of thermocouple probes for 241-AZ-101 waste tank

    International Nuclear Information System (INIS)

    Kanjilal, S.K.

    1994-01-01

    This document reports on the structural analysis of the thermocouple probe to be installed in 241-AZ-101 waste tank. The thermocouple probe is analyzed for normal pump mixing operation and potential earthquake induced loads required by the Hanford Site Design Criteria SDC-4.1

  3. Structural evaluation of thermocouple probes for 241-AZ-101 waste tank

    Energy Technology Data Exchange (ETDEWEB)

    Kanjilal, S.K.

    1994-12-06

    This document reports on the structural analysis of the thermocouple probe to be installed in 241-AZ-101 waste tank. The thermocouple probe is analyzed for normal pump mixing operation and potential earthquake induced loads required by the Hanford Site Design Criteria SDC-4.1.

  4. Tank 241-AZ-101 steam bumping and settling Process Test report

    International Nuclear Information System (INIS)

    Winkler, C.M.

    1995-01-01

    This report summarizes the process test in which the airlift circulators in Tank 241-AZ-101 were shutdown. The test was successful, in that no extreme temperature excursions occurred. Only general data was obtianed through the use of a gamma energy probe

  5. Fatigue properties of magnesium alloy AZ91 processed by severe plastic deformation

    Czech Academy of Sciences Publication Activity Database

    Fintová, Stanislava; Kunz, Ludvík

    2015-01-01

    Roč. 42, FEB (2015), s. 219-228 ISSN 1751-6161 R&D Projects: GA ČR GAP108/10/2001 Institutional support: RVO:68081723 Keywords : AZ91 magnesium alloy * ECAP * Fatigue * Crack initiation Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 2.876, year: 2015 http://www.sciencedirect.com/science/article/pii/S1751616114003713

  6. 77 FR 20356 - Foreign-Trade Zone 277-Western Maricopa County, AZ; Application for Manufacturing Authority...

    Science.gov (United States)

    2012-04-04

    ... Maricopa County, AZ; Application for Manufacturing Authority; Suntech Arizona, Inc., (Solar Panel... facility is used for the manufacture of 275 and 290 watt solar panels for industrial use. Components and... to solar panels (duty-free) for the foreign inputs noted above. Suntech would also be exempt from...

  7. Comparison of Electrochemical Methods for the Evaluation of Cast AZ91 Magnesium Alloy

    Czech Academy of Sciences Publication Activity Database

    Tkacz, J.; Minda, J.; Fintová, Stanislava; Wasserbauer, J.

    2016-01-01

    Roč. 9, č. 11 (2016), č. článku 925. ISSN 1996-1944 Institutional support: RVO:68081723 Keywords : AZ91 magnesium alloy * cathodic polarization curve * anodic polarization curve * linear polarization curve Subject RIV: JK - Corrosion ; Surface Treatment of Materials Impact factor: 2.654, year: 2016 http://www.mdpi.com/1996-1944/9/11/925

  8. In vitro corrosion of magnesium alloy AZ31 — a synergetic influence of glucose and Tris

    Science.gov (United States)

    Li, Ling-Yu; Liu, Bin; Zeng, Rong-Chang; Li, Shuo-Qi; Zhang, Fen; Zou, Yu-Hong; Jiang, Hongwei George; Chen, Xiao-Bo; Guan, Shao-Kang; Liu, Qing-Yun

    2018-05-01

    Biodegradable Mg alloys have generated great interest for biomedical applications. Accurate predictions of in vivo degradation of Mg alloys through cost-effective in vivo evaluations require the latter to be conducted in an environment close to that of physiological scenarios. However, the roles of glucose and buffering agents in regulating the in vivo degradation performance of Mg alloys has not been elucidated. Herein, degradation behavior of AZ31 alloy is investigated by hydrogen evolution measurements, pH monitoring and electrochemical tests. Results indicate that glucose plays a content-dependent role in degradation of AZ31 alloy in buffer-free saline solution. The presence of a low concentration of glucose, i.e. 1.0 g/L, decreases the corrosion rate of Mg alloy AZ31, whereas the presence of 2.0 and 3.0 g/L glucose accelerates the corrosion rate during long term immersion in saline solution. In terms of Tris-buffered saline solution, the addition of glucose increases pH value and promotes pitting corrosion or general corrosion of AZ31 alloy. This study provides a novel perspective to understand the bio-corrosion of Mg alloys in buffering agents and glucose containing solutions.

  9. Selectividad de caña de azúcar en bovinos

    Directory of Open Access Journals (Sweden)

    E. M. Aranda

    2009-01-01

    Full Text Available Se condujo este trabajo con el objetivo de conocer la aceptación del forraje de caña de azúcar integral en la dieta con base de pasto para bovinos adultos fistulados en rumen y duodeno estabulados; para ello, se ofreció pasto estrella africana (Cynodon plectostachyus y caña de azúcar (Saccharum officinarum mezclada con 1% de urea a voluntad, por separado. Se midió la composición de los alimentos, consumo de materia seca, pH ruminal y duodenal. Se utilizaron técnicas de la estadística descriptiva, como la media aritmética y error estándar. La proteína, paredes celulares y hemicelulosa fueron mayores para el pasto estrella. El consumo de MS fue de 46.6 y 38.1% para la caña de azúcar y el pasto, respectivamente; el pH ruminal tuvo valores de 7.3, disminuyendo a 6.7 a las 12 h.; y el pH de la digesta duodenal osciló de 3.7 a 4.7. Se concluye que hubo mayor aceptación por la caña de azúcar y el pH ruminal no indica valores que afecten la celulólisis ruminal.

  10. Corrosion behaviour of laser surface melted magnesium alloy AZ91D

    International Nuclear Information System (INIS)

    Taltavull, C.; Torres, B.; Lopez, A.J.; Rodrigo, P.; Otero, E.; Atrens, A.; Rams, J.

    2014-01-01

    A high power diode laser (HPDL) was used to produce laser surface melting (LSM) treatments on the surface of the Mg alloy AZ91D. Different treatments with different microstructures were produced by varying the laser-beam power and laser-scanning speed. Corrosion evaluation, using hydrogen evolution and electrochemical measurements, led to a relationship between microstructure and corrosion. Most corrosion rates for LSM treated specimens were within the scatter of the as-received AZ91D, whereas some treatments gave higher corrosion rates and some of the samples had corrosion rates lower than the average of the corrosion rate for AZ91D. There were differences in corroded surface morphology. Nevertheless laser treatments introduced surface discontinuities, which masked the effect of the microstructure. Removing these surface defects decreased the corrosion rate for the laser-treated samples. - Highlights: • Corrosion behavior of AZ91D Mg alloys is intimately related with its microstructure. • Laser surface melting treatments allows surface modification of the microstructure. • Different laser parameters can achieve different microstructures. • Controlling laser parameters can produce different corrosion rates and morphologies. • Increase of surface roughness due to laser treatment is relevant to the corrosion rate

  11. Friction stir welded AM50 and AZ31 Mg alloys: Microstructural evolution and improved corrosion resistance

    Energy Technology Data Exchange (ETDEWEB)

    Templeman, Yael [Department of Materials Engineering, Ben Gurion University of the Negev, PO Box 653, Beer Sheva 84105 (Israel); Ben Hamu, Guy [Department of Mechanical Engineering, Sami Shamoon College of Engineering, Ashdod 77245 (Israel); Meshi, Louisa, E-mail: Louisa@bgu.ac.il [Department of Materials Engineering, Ben Gurion University of the Negev, PO Box 653, Beer Sheva 84105 (Israel)

    2017-04-15

    One of the major drawbacks of Mg alloys is poor weldability, caused by porosity formation during conventional fusion welding processes. Friction Stir Welding (FSW) is promising technique in this context since it is a solid state technique. Contradicting results were published in the literature regarding the FSWed Mg alloys joint's properties. Current research was performed in order to investigate the microstructure and corrosion properties of FSWed Mg alloys, studying representatives of two commercial families: wrought AZ31-H24 and die cast AM50. It was found that in both alloys recrystallization occurred during the FSW. In AM50 the mechanism of the recrystallization was continuous, manifested by dislocation rearrangement into sub grain boundaries. In AZ31 discontinuous recrystallization had occurred through grain boundaries migration - twins rotated with respect to the matrix, turning into low angle grain boundaries. Corrosion resistance has improved during the FSW in both alloys to different extents. In the AM50 alloy, the nugget exhibited significantly higher surface potential than the base metal mainly due to the higher Al concentration in the matrix of the nugget, resulting from the dissolution of Al-enrichment and β-Mg{sub 17}Al{sub 12} phase. In the AZ31 alloy, no change in Al concentration had occurred, and the surface potential measured in the nugget was only slightly higher than in the base metal. These results underline the appropriateness of the FSW for Mg alloys since during the conventional welding deterioration of the corrosion resistance occurs. - Highlights: • Following FSW, AZ31-H24 experienced discontinuous recrystallization. • In AZ31 grain boundaries migration occurred, thus twins rotated. • In die cast AM50 continuous recrystallization occurred during the FSW. • In AM50 - dislocations rearranged into sub grain boundaries. • Corrosion resistance has improved during the FSW in both alloys to different extent.

  12. Friction stir welded AM50 and AZ31 Mg alloys: Microstructural evolution and improved corrosion resistance

    International Nuclear Information System (INIS)

    Templeman, Yael; Ben Hamu, Guy; Meshi, Louisa

    2017-01-01

    One of the major drawbacks of Mg alloys is poor weldability, caused by porosity formation during conventional fusion welding processes. Friction Stir Welding (FSW) is promising technique in this context since it is a solid state technique. Contradicting results were published in the literature regarding the FSWed Mg alloys joint's properties. Current research was performed in order to investigate the microstructure and corrosion properties of FSWed Mg alloys, studying representatives of two commercial families: wrought AZ31-H24 and die cast AM50. It was found that in both alloys recrystallization occurred during the FSW. In AM50 the mechanism of the recrystallization was continuous, manifested by dislocation rearrangement into sub grain boundaries. In AZ31 discontinuous recrystallization had occurred through grain boundaries migration - twins rotated with respect to the matrix, turning into low angle grain boundaries. Corrosion resistance has improved during the FSW in both alloys to different extents. In the AM50 alloy, the nugget exhibited significantly higher surface potential than the base metal mainly due to the higher Al concentration in the matrix of the nugget, resulting from the dissolution of Al-enrichment and β-Mg 17 Al 12 phase. In the AZ31 alloy, no change in Al concentration had occurred, and the surface potential measured in the nugget was only slightly higher than in the base metal. These results underline the appropriateness of the FSW for Mg alloys since during the conventional welding deterioration of the corrosion resistance occurs. - Highlights: • Following FSW, AZ31-H24 experienced discontinuous recrystallization. • In AZ31 grain boundaries migration occurred, thus twins rotated. • In die cast AM50 continuous recrystallization occurred during the FSW. • In AM50 - dislocations rearranged into sub grain boundaries. • Corrosion resistance has improved during the FSW in both alloys to different extent.

  13. Tank 241-AZ-101 criticality assessment resulting from pump jet mixing: Sludge mixing simulation

    Energy Technology Data Exchange (ETDEWEB)

    Onishi, Y.; Recknagle, K.

    1997-04-01

    Tank 241-AZ-101 (AZ-101) is one of 28 double-shell tanks located in the AZ farm in the Hanford Site`s 200 East Area. The tank contains a significant quantity of fissile materials, including an estimated 9.782 kg of plutonium. Before beginning jet pump mixing for mitigative purposes, the operations must be evaluated to demonstrate that they will be subcritical under both normal and credible abnormal conditions. The main objective of this study was to address a concern about whether two 300-hp pumps with four rotating 18.3-m/s (60-ft/s) jets can concentrate plutonium in their pump housings during mixer pump operation and cause a criticality. The three-dimensional simulation was performed with the time-varying TEMPEST code to determine how much the pump jet mixing of Tank AZ-101 will concentrate plutonium in the pump housing. The AZ-101 model predicted that the total amount of plutonium within the pump housing peaks at 75 g at 10 simulation seconds and decreases to less than 10 g at four minutes. The plutonium concentration in the entire pump housing peaks at 0.60 g/L at 10 simulation seconds and is reduced to below 0.1 g/L after four minutes. Since the minimum critical concentration of plutonium is 2.6 g/L, and the minimum critical plutonium mass under idealized plutonium-water conditions is 520 g, these predicted maximums in the pump housing are much lower than the minimum plutonium conditions needed to reach a criticality level. The initial plutonium maximum of 1.88 g/L still results in safety factor of 4.3 in the pump housing during the pump jet mixing operation.

  14. Tank 241-AZ-101 criticality assessment resulting from pump jet mixing: Sludge mixing simulation

    International Nuclear Information System (INIS)

    Onishi, Y.; Recknagle, K.

    1997-04-01

    Tank 241-AZ-101 (AZ-101) is one of 28 double-shell tanks located in the AZ farm in the Hanford Site's 200 East Area. The tank contains a significant quantity of fissile materials, including an estimated 9.782 kg of plutonium. Before beginning jet pump mixing for mitigative purposes, the operations must be evaluated to demonstrate that they will be subcritical under both normal and credible abnormal conditions. The main objective of this study was to address a concern about whether two 300-hp pumps with four rotating 18.3-m/s (60-ft/s) jets can concentrate plutonium in their pump housings during mixer pump operation and cause a criticality. The three-dimensional simulation was performed with the time-varying TEMPEST code to determine how much the pump jet mixing of Tank AZ-101 will concentrate plutonium in the pump housing. The AZ-101 model predicted that the total amount of plutonium within the pump housing peaks at 75 g at 10 simulation seconds and decreases to less than 10 g at four minutes. The plutonium concentration in the entire pump housing peaks at 0.60 g/L at 10 simulation seconds and is reduced to below 0.1 g/L after four minutes. Since the minimum critical concentration of plutonium is 2.6 g/L, and the minimum critical plutonium mass under idealized plutonium-water conditions is 520 g, these predicted maximums in the pump housing are much lower than the minimum plutonium conditions needed to reach a criticality level. The initial plutonium maximum of 1.88 g/L still results in safety factor of 4.3 in the pump housing during the pump jet mixing operation

  15. Characterization of the first core sample of neutralized current acid waste from double-shell tank 101-AZ

    International Nuclear Information System (INIS)

    Peterson, M.E.; Scheele, R.D.; Tingey, J.M.

    1989-09-01

    In FY 1989, Westinghouse Hanford Company (WHC) successfully obtained four core samples (totaling seven segments) of neutralized current acid waste (NCAW) from double-shell tanks (DSTs) 101-AZ and 102-AZ. A segment was a 19-in.-long and 1-in.-diameter cylindrical sample of waste. A core sample consisted of enough 19-in.-long segments to obtain the waste of interest. Three core samples were obtained from DST 101-AZ and one core sample from DST 102-AZ. Two DST 101-AZ core samples consisted of two segments per core, and the third core sample consisted of only one segment. The third core consisted of the solids from the bottom of the tank and was used to determine the relative abrasiveness of this NCAW. The DST 102-AZ core sample consisted of two segments. The core samples were transported to the Pacific Northwest Laboratory (PNL), where the waste was extruded from its sampler and extensively characterized. A characterization plan was followed that simulated the processing of the NCAW samples through retrieval, pretreatment and vitrification process steps. Physical, rheological, chemical and radiochemical properties were measured throughout the process steps. The characterization of the first core sample from DST 101-AZ was completed, and the results are provided in this report. The results for the other core characterizations will be reported in future reports. 3 refs., 13 figs., 10 tabs

  16. Análisis del perfil de azúcares en la autentificación de zumos de frutas

    OpenAIRE

    Úbeda Gallego, Ana

    2013-01-01

    El objetivo general ha sido estudiar el perfil de azúcares por HPAEC-PAD para la autentificación de zumos de frutas de naranja, manzana y piña. Este objetivo general se ha dividido en los siguientes objetivos parciales: 1. Optimizar el método de análisis de azúcares por HPAEC-PAD. Para ello se han ensayado distintas concentraciones de NaOH en la fase móvil y distinta velocidad de flujo. Se han analizando muestras de azúcares, zumos concentrados y zumos comerciales. 2. Determinar el p...

  17. AMPLIFIKASI DAN IDENTIFIKASI MUTASI REGIO PROMOTER inhA PADA ISOLAT Mycobacterium tuberculosis MULTIDRUG RESISTANCE DENGAN TEKNIK POLYMERASE CHAIN REACTION

    Directory of Open Access Journals (Sweden)

    Devita Kusdianingrum

    2014-10-01

    Full Text Available ABSTRAK: Sekitar 8-20% isolate M. tuberculosis yang resisten terhadap isoniazid diketahui telah mengalami mutasi pada posisi regio promoter inhA [1]. Untuk memperoleh titik mutasi pada regio promoter, maka amplifikasi fragmen target perlu untuk dilakukan. Tujuan dilakukannya penelitian ini adalah untuk mengamplifikasi regio promoter inhA, mengetahui ada tidaknya mutasi dan jenis mutasi pada isolat 134 MDR-TB. Tahap isolasi DNA dilakukan menggunakan metode Boom yang telah dimodifikasi. Fragmen target diamplifikasi dengan teknik PCR menggunakan sepasang primer (forward primer 5’ ACATACCTGCTGCGCAAT 3’ dan reverse primer 5’ CTCCGGTAACCAGGACT GAA 3’. Amplikon disekuensing secara satu arah menggunakan forward primer. Analisis homologi dilakukan menggunakan program online BLASTn, sementara identifikasi mutasi dilakukan menggunakan software MEGA4. Hasil penelitian menunjukkan bahwa analisis homologi isolate 134 terhadap M. tuberculosis H37Rv adalah sebesar 99%. Tahap analisis mutasi menemukan terjadinya perubahan sitosin menjadi timin (CàT pada posisi -15 isolat 134 MDR-TB   ABSTRACT: Approximately 8-20% M. tuberculosis isolates that are resistant to isoniazid habe been known to have a mutation in inhA promoter region [1]. To find the mutation in inhA promoter region, it is necessary to carry out the amplification of the target fragment. The purpose of this research were to amplify the inhA promoter region and to find out if there is a mutation and type of mutation at MDR-TB isolate. DNA isolation was done by a modified Boom method. Target fragment was amplified by a pair primer (forward primer 5’ ACATACCTGCTGCGCAAT 3’ and reverse primer 5’ CTCCGGTAACCAGGACT GAA 3’ using Polymerase Chain Reaction (PCR technique. Amplicon was sequenced in one forward direction. Homology analysis was conducted by online BLASTn program, while the mutation was identified by MEGA4. The result of this research showed that homology analysis of 134 was homolog

  18. Pengaruh Strategi SQ4R Tipe Bantuan Multimedia vs Buku Teks, Pengetahuan Awal, Gaya Belajar Kolb terhadap Hasil Belajar Bahasa Inggris Teknik

    Directory of Open Access Journals (Sweden)

    Meiti Leatemia

    2014-06-01

    Full Text Available Penelitian ini bertujuan menyelidiki pengaruh strategi SQ4R tipe bantuan multimedia versus buku teks, pengetahuan awal dan gaya belajar terhadap hasil belajar bahasa Inggris Teknik. Subjek penelitian adalah 96 mahasiswa  Teknik Sipil dan Mesin Politeknik Negeri Ambon tahun akademik 2011-2012. Desain eksperimen menggunakan kuasi versi  factorial  (2 x 2 x 2 pre test-post test non-equivalent control group design. Analisis data menggunakan statistik Three Ways ANOVA. Pengujian hipotesis dilakukan pada taraf signifikansi 5% atau á=0,5  menggunakan SPSS 17.0 for windows. Hasil penelitian menunjukan bahwa (1 Ada perbedaan yang signifikan hasil belajar  antara kelompok strategi SQ4R tipe bantuan multimedia dan buku teks, (2 ada perbedaan yang signifikan hasil belajar antara kelompok pengetahuan awal tinggi dan rendah, (3 tidak ada perbedaan yang signifikan antara pembelajar diverger dan assimilator,  (4 tidak ada pengaruh interaksi antara strategi SQ4R tipe bantuan dengan pengetahuan awal terhadap hasil belajar, (5 tidak ada pengaruh interaksi antara strategi SQ4R tipe bantuan dengan gaya belajar terhadap hasil belajar, (6 ada pengaruh interaksi an-tara pengetahuan awal dengan gaya belajar terhadap hasil belajar, dan, (7 ada pengaruh interaksi antara strategi SQ4R tipe bantuan, pengetahuan awal dan gaya belajar terhadap hasil belajar. Kata kunci: strategi SQ4R tipe bantuan, multimedia, pengetahuan awal, gaya belajar,  hasil  belajar

  19. PELAKSANAAN PEMBELAJARAN BERBASIS MULTIMEDIA KOMPUTER UNTUK MENINGKATKAN PEMAHAMAN, SIKAP, DAN KETERAMPILAN DALAM MEMBUBUT ULIR SEGITIGA PADA KOMPETENSI KEAHLIAN TEKNIK PEMESINAN SMK

    Directory of Open Access Journals (Sweden)

    Bambang Eko Soebekti Djatmiko

    2013-07-01

    Full Text Available The application of multimedia based learning to improve the under­standing, attitudes, and skills on lathe triangle screw at Mechanical Engineering Com­peten­cies in Vocational High School. The purpose of this study is to improve the understand­ing, attitudes and skills competencies on lathe triangle screw using computer-based multi­media. This study is designed in 3 cycles. The subjects of the study are thirty-five students at the X grade of Mechanical Engineering competencies.The results of the study show that the use of multimedia based learning is able to enhance students' cognitive, affective (attitude and psychomotoric abilities as well as to improve student achievement. Tujuan penelitian ini adalah meningkatkan pemahaman, sikap, dan ke­te­ram­pilan membubut ulir segitiga siswa pada Kompetensi Keahlian Teknik Pemesinan SMK. Rancangan penelitian ini adalah tindakan kelas yang dilaksanakan dalam tiga siklus. Subjek penelitian adalah siswa kelas X program keahlian teknik pemesinan yang berjumlah 35 siswa. Hasil penelitian menunjukkan penggunaan pembelajaran berbasis multimedia dapat meningkatkan kemampuan kognitif siswa; dapat meningkat­kan kemampuan afektif (sikap siswa; dapat meningkatkan kemampuan psikomotorik siswa; dan dapat meningkatkan hasil belajar siswa.

  20. Perbandingan Hasil Belajar Teknik Dasar Pukulan Pada Permainan Tenis Meja Antara Yang Langsung Mengunakan Net Dengan Tanpa Menggunakan Net Terlebih Dahulu

    Directory of Open Access Journals (Sweden)

    Indra Safari

    2016-07-01

    Full Text Available Abstrak   Tujuan penelitian ini adalah untuk mengkaji antara hasil belajar langsung menggunakan net dengan yang tanpa menggunakan net terlebih dahulu terhadap peningkatan penguasaan teknik dasar pukulan pada permainan tenis meja bagi pemula.Untuk memecahkan permasalahan tersebut penulis menggunakan metode eksperimen, sedangkan data yang diperoleh adalah melalui eksperimen lapangan. Populasi yang digunakan dalam penelitian ini adalah siswa SDN Muhammadiyah III Bandung, sedangkan untuk sampelnya yaitu siswa kelas 4 s/d 6 (putera dan yang termasuk dalam kategori umur pemula. Hasil penelitian ini menunjukkan bahwa walaupun secara perhitungan statistic kedua cara pembelajaran tersebut tidak ada perbedaan yang berarti (signifikan, tetapi secara fakta di lapangan dengan frekuensi tiga kali dalam seminggu dengan cara pembelajaran tanpa menggunakan net terlebih dahulu memberikan perbedaan dalam perbedaan mean, yaitu yang langsung menggunakan net (0 – 89,0 sedangkan yang tanpa menggunakan net terlebih dahulu (0 – 93,0 dengan taraf nyata 0,05. Kata Kunci: teknik dasar, menggunakan net dan tanpa menggunakan net

  1. Peningkatan Prestasi Belajar CAD Mahasiswa Teknik Otomotif Non-Reguler FT UNY melalui Pembuatan “Pohon Kata” Perintah dalam Program AutoCAD

    Directory of Open Access Journals (Sweden)

    Martubi Martubi

    2010-05-01

    Full Text Available Penelitian ini bertujuan meningkatkan prestasi belajar mata kuliah Computer Aided Design (CAD mahasiswa prodi Teknik Otomotif Non-Reguler yang dinyatakan dalam bentuk rerata nilai akhir semester yang berasal dari komponen nilai tugas harian, nilai ujian tengah semester dan nilai ujian akhir semester. Penelitian quasi-eksperimen ini terdiri dari tahapan penelitian diawali dengan penyusunan materi pembelajaran sejumlah pokok bahasan tertentu dalam satu job sheet (lembar kerja, dilanjutkan dengan pembuatan bantuan “Pohon Kata” perintah dalam Auto CAD kepada kelas eksperimen yang ditentukan secara random dari dua kelas peserta kuliah Auto CAD pada Semester Genap 2008/2009. Kedua kelas diamati prestasinya, baik kecepatan penyelesaiannya maupun kualitas kebenaran gambarnya. Prestasi belajar kedua kelas juga diukur melalui pemberian ujian tengah semester dan ujian akhir semester. Setelah data prestasi kedua kelas terkumpul dilanjutkan dengan analisis statistik melalui uji beda (t-test setelah sebelumnya dilakukan uji persyaratan analisis yang ternyata dapat dipenuhi. Hasil penelitian ini disimpulkan bahwa: prestasi belajar CAD mahasiswa pada kelas yang diberi perlakuan strategi pembelajaran menggunakan “Pohon Kata” perintah dalam Program Auto CAD lebih baik dibanding prestasi belajar CAD mahasiswa pada kelas yang tidak diberi perlakuan (75,41>70,89, dengan demikian pembelajaran CAD menggunakan media “Pohon Kata” perintah dalam Program Auto CAD dapat meningkatkan prestasi belajar mahasiswa Teknik Otomotif Program Non-Reguler.

  2. Bioetanol de la caña de azúcar

    Directory of Open Access Journals (Sweden)

    N. Aguilar-Rivera

    2007-01-01

    Full Text Available La búsqueda de la viabilidad y desarrollo de la agroindustria de la caña de azúcar es ya una política imperativa. La producción de caña y azúcar constituyen la principal agroindustria del país, con presencia en 57 ingenios azucareros, localizados en 15 estados de la república. Sin embargo, la actual ineficiencia productiva, altos costos y otras causas —como la entrada de jarabe de maíz de alta fructosa (HFCS de menor costo— han desplazado el consumo interno de azúcar de caña, principalmente en bebidas embotelladas. Todos estos factores han contribuido a la actual y prolongada crisis del sector azucarero. Por lo tanto, la industria debe reestructurarse y reducir la producción de azúcar hacia la competitividad, con la alternativa del etanol combustible en la búsqueda de un futuro para la industria azucarera en México. Con la producción de etanol (EtOH a gran escala, por parte de los ingenios azucareros, es posible visualizar un nuevo y futuro mercado de uso de energías renovables en México, oportunidades para la exportación e incrementar los beneficios ambientales y económicos a través de su uso. La flexibilidad de la producción combinada, de azúcar y etanol en los ingenios, permitirá alcanzar esquemas y objetivos ambientales como nación. Para la industria azucarera, su mayor competidesafío, en este sentido, representa disminuir los costos actuales de producción de etanol a través del uso de la ingeniería genética, uso de diferentes materias primas y la totalidad de la planta de caña de azúcar e introducir mejoras tecnológicas.

  3. Desarrollo de las pequeñas industrias rurales de la caña de azúcar en iberoamerica: Melaza, Panela y Azúcar Moreno

    OpenAIRE

    Da Silva, Fabio César; Cesar, Marco; Hernández Díaz-Ambrona, Carlos Gregorio

    2010-01-01

    Los niveles de producción de azúcar en los últimos años crecen a un ritmo semejante al crecimiento poblacional. El fabricante debe estar atento a las características de calidad del producto que su mercado o comprador/consumidor exige y la facilidad de transporte al centro consumidor. La legislación debe especificar los requisitos mínimos pero el fabricante debe tener como desafío ofrecer un producto de calidad y reducir los riesgos ambientales en sus cultivos en función de la aptitud de la...

  4. AZ-101 Mixer Pump Demonstration Data Acquisition System and Gamma Cart Data Acquisition Control System Software Configuration Management Plan

    International Nuclear Information System (INIS)

    WHITE, D.A.

    1999-01-01

    This Software Configuration Management Plan (SCMP) provides the instructions for change control of the AZ1101 Mixer Pump Demonstration Data Acquisition System (DAS) and the Sludge Mobilization Cart (Gamma Cart) Data Acquisition and Control System (DACS)

  5. A biodegradable AZ91 magnesium alloy coated with a thin nanostructured hydroxyapatite for improving the corrosion resistance.

    Science.gov (United States)

    Mukhametkaliyev, T M; Surmeneva, M A; Vladescu, A; Cotrut, C M; Braic, M; Dinu, M; Vranceanu, M D; Pana, I; Mueller, M; Surmenev, R A

    2017-06-01

    The main aim of this study was to investigate the properties of an AZ91 alloy coated with nanostructured hydroxyapatite (HA) prepared by radio frequency (RF) magnetron sputtering. The bioactivity and biomineralization of the AZ91 magnesium alloy coated with HA were investigated in simulated body fluid (SBF) via an in vitro test. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) analyses were performed. The samples were immersed in SBF to study the ability of the surface to promote the formation of an apatite layer as well as corrosion resistance and mass change of the HA-coated AZ91 alloy. Electrochemical tests were performed to estimate the corrosion behaviour of HA-coated and uncoated samples. The results revealed the capability of the HA coating to significantly improve the corrosion resistance of the uncoated AZ91 alloy. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. In vitro corrosion of pure magnesium and AZ91 alloy?the influence of thin electrolyte layer thickness

    OpenAIRE

    Zeng, Rong-Chang; Qi, Wei-Chen; Zhang, Fen; Li, Shuo-Qi

    2016-01-01

    In vivo degradation predication faces a huge challenge via in vitro corrosion test due to the difficulty for mimicking the complicated microenvironment with various influencing factors. A thin electrolyte layer (TEL) cell for in vitro corrosion of pure magnesium and AZ91 alloy was presented to stimulate the in vivo corrosion in the micro-environment built by the interface of the implant and its neighboring tissue. The results demonstrated that the in vivo corrosion of pure Mg and the AZ91 all...

  7. TEKNIK PEMERIKSAAN PADA MIKROTROPIA

    Directory of Open Access Journals (Sweden)

    Lona Diolanda

    2014-12-01

    Full Text Available AbstrakMikrotropia merupakan strabismus sudut kecil (kurang dari 5˚ yang disertai dengan ARC dan ketajaman stereopsis yang berkurang atau tidak ada sama sekali. Mikrotropia sering disertai dengan sindroma monofiksasi. Ini ditandai dengan adanya fusi perifer dan supresi di daerah sentral (foveal suppresion scotoma mata yang mengalami deviasi. Mikrotropia dapat dibagi menjadi dua bentuk yaitu mikrotropia primer (mikrotropia with identity dan mikrotropia without identity dan mikrotropia sekunder. Pemeriksaan diagnostik pada mikrotropia bertujuan untuk menunjukkan adanya penglihatan binokular perifer tanpa disertai penglihatan binokular sentral pada penderita mikrotropia. Pada makalah ini akan membahas karakteristik klinik dan pemeriksaan mikrotropia.AbstractMicrotropia is defined as strabismus with a small deviation (less than 5˚, combined with Anomalous Retinal Correspondence (ARC and reduced or absent stereoacuity. Microtropia is often accompanied by monofixation syndrome. It is characterized by peripheral fusion and suppression in the central area (foveal suppresion scotoma of the misaligned eye. There are two forms of microtropia: primary microtropia (microtropia with identity; microtropia without identity and secondary microtropia. Diagnostic examination of microtropia aims at demonstrating existence of peripheral binocular vision but no central binocular vision. This paper will discuss about clinical characteristic and diagnostic of microtropia.

  8. Evaluation of AY/AZ tank farm ventilation system during aging waste retrieval operations

    International Nuclear Information System (INIS)

    Wong, J.J.; Waters, E.D.

    1995-01-01

    Waste Management is currently planning to demonstrate mobilization of radioactive waste sludges in Tank 101-AZ beginning in October 1991. The retrieval system being designed will utilize mixer pumps that generate high-velocity, high-volume submerged liquid jets to mobilize settled solids. There is concern that these jets may also generate radioactive aerosols, some of which may be carried into the tank Ventilation system. The purpose of this study is to determine if the current AY/AZ ventilation system or the proposed ventilation system upgrade (Project W-030) will provide adequate deentrainment of liquid and solid aerosols during mixer pump operations, or if the radioactive aerosols will overload the HEPA filters

  9. Effect of alternating voltage treatment on corrosion resistance of AZ91D magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X. [Corrosion and Protection Laboratory, Key Laboratory of Superlight Materials and Surface Technology (Harbin Engineering University), Ministry of Education, Harbin (China); Zhang, T.; Shao, Y.; Meng, G.; Wang, F. [Corrosion and Protection Laboratory, Key Laboratory of Superlight Materials and Surface Technology (Harbin Engineering University), Ministry of Education, Harbin (China); State Key Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, Shenyang (China)

    2012-06-15

    AZ91D magnesium alloy was treated by the alternating voltage (AV) treatment technique. The optimal AV-treatment parameters of the alloy were determined by orthogonal experiments. Polarization curve, electrochemical impedance spectroscopy (EIS), and scanning electrochemical microscopy (SECM) were used to understand the effect of AV-treatment on the corrosion resistance of the alloy. AFM, contact angle, and XPS were employed to investigate further the influence of AV-treatment on the properties of the surface film formed on the alloy after AV-treatment. The results showed that a uniform and stable film was formed and the corrosion resistance of AZ91D magnesium alloy was significantly improved after AV-treatment. This was caused by the noticeable change of the chemical structure and semi-conducting properties of the surface film after AV-treatment. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Influence of Zeolite Coating on the Corrosion Resistance of AZ91D Magnesium Alloy

    Directory of Open Access Journals (Sweden)

    P. Chakraborty Banerjee

    2014-08-01

    Full Text Available The protective performance of zeolite coating on AZ91D magnesium alloy was evaluated using potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS in 0.1 M sodium chloride solution (NaCl. Electrical equivalent circuit (EEC was developed based upon hypothetical corrosion mechanisms and simulated to correspond to the experimental data. The morphology and the chemical nature of the coating were characterized by scanning electron microscopy (SEM and X-ray diffraction (XRD analysis. Post corrosion morphologies of the zeolite coated and the uncoated AZ91D alloy were investigated using SEM. The corrosion resistance of the zeolite coated specimen was at least one order of magnitude higher than the uncoated specimen.

  11. Project W-314 specific test and evaluation plan for AZ tank farm upgrades

    International Nuclear Information System (INIS)

    Hays, W.H.

    1998-01-01

    The purpose of this Specific Test and Evaluation Plan (STEP) is to provide a detailed written plan for the systematic testing of modifications made by the addition of the SN-631 transfer line from the AZ-O1A pit to the AZ-02A pit by the W-314 Project. The STEP develops the outline for test procedures that verify the system's performance to the established Project design criteria. The STEP is a lower tier document based on the W-314 Test and Evaluation P1 an (TEP). Testing includes Validations and Verifications (e.g., Commercial Grade Item Dedication activities, etc), Factory Tests and Inspections (FTIs), installation tests and inspections, Construction Tests and Inspections (CTIs), Acceptance Test Procedures (ATPs), Pre-Operational Test Procedures (POTPs), and Operational Test Procedures (OTPs). The STEP will be utilized in conjunction with the TEP for verification and validation

  12. Diffusion and solubility of Au implanted into the AZ1350 photoresist

    International Nuclear Information System (INIS)

    Soares, M.R.F.; Kaschny, J.R.A.; Santos, J.H.R. dos; Amaral, L.; Behar, M.; Fink, D.

    2000-01-01

    In the present paper we report diffusion and solubility results for Au into the photoresist AZ1350. Au was implanted into AZ1350 films at very low energy (E=20 keV) and fluences (PHI=10 12 and 5x10 12 Au/cm 2 ). In this way the radiation damage introduced by the implantation process was minimized and cluster formation was avoided. Annealing was performed in the 150-300 deg. C temperature range and the as implanted and thermal treated samples were analyzed using the Rutherford backscattering (RBS) technique. For the lowest implantation fluence the results have shown a regular atomic diffusion process characterized by an activation energy of E a =640 meV. Instead, for PHI=5x10 12 Au/cm 2 the diffusional mechanism has revealed the effects of the radiation damage. In addition solubility measurements indicate that the solubility limit at 250 deg. C is of the order 0.3 at.%

  13. Corrosion behavior of biodegradable material AZ31 coated with beeswax-colophony resin

    Science.gov (United States)

    Gumelar, Muhammad Dikdik; Putri, Nur Ajrina; Anggaravidya, Mahendra; Anawati, Anawati

    2018-05-01

    Magnesium (Mg) and its alloys are potential candidates for biodegradable implant materials owing to their ability to degrade spontaneously in a physiological environment. However, the degradation rate is still considered too fast in human body solution. A coating is typically applied to slowdown corrosion rate of Mg alloys. In this work, an organic coating of mixture beeswax-colophony with ratios of 40-60, 50-50, and 60-40 in wt% was synthesized and applied on commercial magnesium alloyAZ31. The coated specimens were then characterized with SEM and XRF. The corrosion behavior of the coated specimens was evaluated by immersion test in 0.9 wt% NaCl solution at 37°C for 14 days. The results indicated that the coating material improved the corrosion resistance of the AZ31 alloy.

  14. Surface roughness optimization in machining of AZ31 magnesium alloy using ABC algorithm

    Directory of Open Access Journals (Sweden)

    Abhijith

    2018-01-01

    Full Text Available Magnesium alloys serve as excellent substitutes for materials traditionally used for engine block heads in automobiles and gear housings in aircraft industries. AZ31 is a magnesium alloy finds its applications in orthopedic implants and cardiovascular stents. Surface roughness is an important parameter in the present manufacturing sector. In this work optimization techniques namely firefly algorithm (FA, particle swarm optimization (PSO and artificial bee colony algorithm (ABC which are based on swarm intelligence techniques, have been implemented to optimize the machining parameters namely cutting speed, feed rate and depth of cut in order to achieve minimum surface roughness. The parameter Ra has been considered for evaluating the surface roughness. Comparing the performance of ABC algorithm with FA and PSO algorithm, which is a widely used optimization algorithm in machining studies, the results conclude that ABC produces better optimization when compared to FA and PSO for optimizing surface roughness of AZ 31.

  15. Surface characterization and cytocompatibility evaluation of silanized magnesium alloy AZ91 for biomedical applications

    Directory of Open Access Journals (Sweden)

    Agnieszka Witecka, Akiko Yamamoto, Henryk Dybiec and Wojciech Swieszkowski

    2012-01-01

    Full Text Available Mg alloys with high Al contents have superior corrosion resistance in aqueous environments, but poor cytocompatibility compared to that of pure Mg. We have silanized the cast AZ91 alloy to improve its cytocompatibility using five different silanes: ethyltriethoxysilane (S1, 3-aminopropyltriethoxysilane (S2, 3-isocyanatopyltriethoxysilane (S3, phenyltriethoxysilane (S4 and octadecyltriethoxysilane (S5. The surface hydrophilicity/hydrophobicity was evaluated by water contact angle measurements. X-ray photoelectron analysis was performed to investigate the changes in surface states and chemical composition. All silane reagents increased adsorption of the albumin to the modified surface. In vitro cytocompatibility evaluation revealed that silanization improved cell growth on AZ91 modified by silane S1. Measurement of the concentration of Mg2+ ions released during the cell culture indicated that silanization does not affect substrate degradation.

  16. Evolution of twinning in extruded AZ31 alloy with bimodal grain structure

    Energy Technology Data Exchange (ETDEWEB)

    Garcés, G., E-mail: ggarces@cenim.csic.es [Department of Physical Metallurgy, National Centre for Metallurgical Research CENIM-CSIC, Av. De Gregorio del Amo 8, 28040 Madrid (Spain); Oñorbe, E. [CIEMAT, Division of Structural Materials, Avenida Complutense, 40, 28040 Madrid (Spain); Gan, W. [German Engineering Materials Science Centre at MLZ, Helmholtz-Zentrum Geesthacht, Lichtebergstr. 1, D-85747 Garching (Germany); Máthis, K. [Department of Physics of Materials, Faculty of Mathematics and Physics, Charles University, KeKarlovu 5, 121 16 Praha 2 (Czech Republic); Tolnai, D. [Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Str. 1, 21502 Geesthacht (Germany); Horváth, K. [Department of Physics of Materials, Faculty of Mathematics and Physics, Charles University, KeKarlovu 5, 121 16 Praha 2 (Czech Republic); Pérez, P.; Adeva, P. [Department of Physical Metallurgy, National Centre for Metallurgical Research CENIM-CSIC, Av. De Gregorio del Amo 8, 28040 Madrid (Spain)

    2017-04-15

    Twinning in extruded AZ31 alloy with a bimodal grain structure is studied under compression along the extrusion direction. This study has combined in-situ measurements during the compression tests by Synchrotron Radiation Diffraction and Acoustic Emission techniques and the evaluation of the microstructure and texture in post-mortem compression samples deformed at different strains. The microstructure of the alloy is characterized by the coexistence of large areas of fine dynamic recrystallized grains and coarse non-recrystallized grains elongated along extrusion direction. Twinning occurs initially in large elongated grains before the macroscopic yield stress which is controlled by the twinning in equiaxed dynamically recrystallized grains. - Highlights: • The AZ31 extruded at low temperature exhibits a bimodal grains structure. • Twinning takes place before macroscopic yielding in coarse non-DRXed grains. • DRXed grains controls the beginning of plasticity in magnesium alloys with bimodal grain structure.

  17. Corrosion behavior of friction stir welded AZ31B Mg alloy - Al6063 alloy joint

    Directory of Open Access Journals (Sweden)

    B. Ratna Sunil

    2016-12-01

    Full Text Available In the present work, AZ31B Mg alloy and Al6063 alloy-rolled sheets were successfully joined by friction stir welding. Microstructural studies revealed a sound joint with good mechanical mixing of both the alloys at the nugget zone. Corrosion performance of the joint was assessed by immersing in 3.5% NaCl solution for different intervals of time and the corrosion rate was calculated. The joint has undergone severe corrosion attack compared with both the base materials (AZ31B and Al6063 alloys. The predominant corrosion mechanism behind the high corrosion rate of the joint was found to be high galvanic corrosion. From the results, it can be suggested that the severe corrosion of dissimilar Mg–Al joints must be considered as a valid input while designing structures intended to work in corroding environment.

  18. Effect of Rare Earth on Corrosion Products and Impedance Behavior of AZ91 Magnesium Alloy Under Dry-wet Cycles

    Directory of Open Access Journals (Sweden)

    ZHAO Xi

    2017-04-01

    Full Text Available The effect of mischmetal of lanthanum and cerium on the composition and structure of the corrosion products on the surface of AZ91 Mg alloy in deicing salt solution under dry-wet cycles was investigated by scanning electron microscopy (SEM, X-ray diffraction (XRD and energy dispersive spectrometer (EDS. The results show that the corrosion products of AZ91 Mg alloy without mischmetal addition (La,Ce are mainly composed of Mg(OH2, MgO, CaCO3 and Mg6Al2CO3(OH16·4H2O; and (La,CeAlO3 can be found in the products of AZ91 with mischmetal addition, meanwhile dense layer occurs in the corrosion products. Electrochemical impedance spectroscopy (EIS measurements show that the charge transfer resistance of AZ91 alloy with mischmetal addition tested in the same dry-wet cycles is much higher than that of AZ91 alloy, the addition of mischmetal helps to reduce the dispersing effect of impedance spectroscopy, indicating that the corrosion resistance of AZ91 Mg alloy and the stability of corrosion product films can be improved by mischmetal of La and Ce.

  19. TIP48/Reptin and H2A.Z requirement for initiating chromatin remodeling in estrogen-activated transcription.

    Directory of Open Access Journals (Sweden)

    Mathieu Dalvai

    2013-04-01

    Full Text Available Histone variants, including histone H2A.Z, are incorporated into specific genomic sites and participate in transcription regulation. The role of H2A.Z at these sites remains poorly characterized. Our study investigates changes in the chromatin environment at the Cyclin D1 gene (CCND1 during transcriptional initiation in response to estradiol in estrogen receptor positive mammary tumour cells. We show that H2A.Z is present at the transcription start-site and downstream enhancer sequences of CCND1 when the gene is poorly transcribed. Stimulation of CCND1 expression required release of H2A.Z concomitantly from both these DNA elements. The AAA+ family members TIP48/reptin and the histone variant H2A.Z are required to remodel the chromatin environment at CCND1 as a prerequisite for binding of the estrogen receptor (ERα in the presence of hormone. TIP48 promotes acetylation and exchange of H2A.Z, which triggers a dissociation of the CCND1 3' enhancer from the promoter, thereby releasing a repressive intragenic loop. This release then enables the estrogen receptor to bind to the CCND1 promoter. Our findings provide new insight into the priming of chromatin required for transcription factor access to their target sequence. Dynamic release of gene loops could be a rapid means to remodel chromatin and to stimulate transcription in response to hormones.

  20. Comparison of simulants to actual neutralized current acid waste: process and product testing of three NCAW core samples from Tanks 101-AZ and 102-AZ

    Energy Technology Data Exchange (ETDEWEB)

    Morrey, E.V.; Tingey, J.M.; Elliott, M.L.

    1996-10-01

    A vitrification plant is planned to process the high-level waste (HLW) solids from Hanford Site tanks into canistered glass logs for disposal in a national repository. Programs were established within the Pacific Northwest Laboratory Vitrification Technology Development (PVTD) Project to test and model simulated waste to support design, feed processability, operations, permitting, safety, and waste-form qualification. Parallel testing with actual radioactive waste was performed on a laboratory-scale to confirm the validity of using simulants and glass property models developed from simulants. Laboratory-scale testing has been completed on three radioactive core samples from tanks 101-AZ and 102-AZ containing neutralized current acid waste (NCAW), which is one of the first waste types to be processed in the high-level waste vitrification plant under a privatization scenario. Properties of the radioactive waste measured during process and product testing were compared to simulant properties and model predictions to confirm the validity of simulant and glass property ,models work. This report includes results from the three NCAW core samples, comparable results from slurry and glass simulants, and comparisons to glass property model predictions.

  1. Comparison of simulants to actual neutralized current acid waste: Process and product testing of three NCAW core samples from Tanks 101-AZ and 102-AZ

    Energy Technology Data Exchange (ETDEWEB)

    Morrey, E.V.; Tingey, J.M.

    1996-04-01

    A vitrification plant is planned to process the high-level waste (HLW) solids from Hanford Site tanks into canistered glass logs for disposal in a national repository. Programs have been established within the Pacific Northwest Laboratory Vitrification Technology Development (PVTD) Project to test and model simulated waste to support design, feed processability, operations, permitting, safety, and waste-form qualification. Parallel testing with actual radioactive waste is being performed on a laboratory-scale to confirm the validity of using simulants and glass property models developed from simulants. Laboratory-scale testing has been completed on three radioactive core samples from tanks 101-AZ and 102-AZ containing neutralized current acid waste (NCAW), which is one of the first waste types to be processed in the high-level waste vitrification plant under a privatization scenario. Properties of the radioactive waste measured during process and product testing were compared to simulant properties and model predictions to confirm the validity of simulant and glass property models work. This report includes results from the three NCAW core samples, comparable results from slurry and glass simulants, and comparisons to glass property model predictions.

  2. Mechanical properties of AZ31 alloy processed by a green metallurgy route; Propiedades mecanicas de la aleacion AZ31 procesada por una ruta eco-sostenible

    Energy Technology Data Exchange (ETDEWEB)

    D' Enrico, F.; Garces, G.; Hofer, M.; Kim, S. K.; Perez, P.; Cabeza, S.; Adeva, P.

    2013-07-01

    Recently it has been proved that molding of defect-free components of various commercial alloys of magnesium can be carried out successfully when small amounts of CaO are added to the melt, making unnecessary the use of SF{sub 6} coverage. In the case of AZ alloys, this process also remarkably improves their mechanical properties not only by the greater cleaning of alloys but also by the formation of CaAl{sub 2} phase. This work, part of the Green project Metallurgy (http://www.green-metallurgy.eu) funded by the European Union (LIFE+2009), studies the influence of different CaO additions on the microstructure and mechanical properties of AZ31 Eco-Mg alloy. The alloy was processed by a conventional route involving extrusion of as-cast rods as well as by a powder metallurgy route (PM) using chips as starting material. The objective was to analyze the viability of recycling machining chips to manufacture components for the automobile industry and transportation in general, because of its low cost and environmental impact. It has been demonstrated that alloys processed from chips exhibit the highest tensile stress values, close to 320 MPa. (Author)

  3. Comparison of simulants to actual neutralized current acid waste: process and product testing of three NCAW core samples from Tanks 101-AZ and 102-AZ

    International Nuclear Information System (INIS)

    Morrey, E.V.; Tingey, J.M.; Elliott, M.L.

    1996-10-01

    A vitrification plant is planned to process the high-level waste (HLW) solids from Hanford Site tanks into canistered glass logs for disposal in a national repository. Programs were established within the Pacific Northwest Laboratory Vitrification Technology Development (PVTD) Project to test and model simulated waste to support design, feed processability, operations, permitting, safety, and waste-form qualification. Parallel testing with actual radioactive waste was performed on a laboratory-scale to confirm the validity of using simulants and glass property models developed from simulants. Laboratory-scale testing has been completed on three radioactive core samples from tanks 101-AZ and 102-AZ containing neutralized current acid waste (NCAW), which is one of the first waste types to be processed in the high-level waste vitrification plant under a privatization scenario. Properties of the radioactive waste measured during process and product testing were compared to simulant properties and model predictions to confirm the validity of simulant and glass property ,models work. This report includes results from the three NCAW core samples, comparable results from slurry and glass simulants, and comparisons to glass property model predictions

  4. Comparison of simulants to actual neutralized current acid waste: Process and product testing of three NCAW core samples from Tanks 101-AZ and 102-AZ

    International Nuclear Information System (INIS)

    Morrey, E.V.; Tingey, J.M.

    1996-04-01

    A vitrification plant is planned to process the high-level waste (HLW) solids from Hanford Site tanks into canistered glass logs for disposal in a national repository. Programs have been established within the Pacific Northwest Laboratory Vitrification Technology Development (PVTD) Project to test and model simulated waste to support design, feed processability, operations, permitting, safety, and waste-form qualification. Parallel testing with actual radioactive waste is being performed on a laboratory-scale to confirm the validity of using simulants and glass property models developed from simulants. Laboratory-scale testing has been completed on three radioactive core samples from tanks 101-AZ and 102-AZ containing neutralized current acid waste (NCAW), which is one of the first waste types to be processed in the high-level waste vitrification plant under a privatization scenario. Properties of the radioactive waste measured during process and product testing were compared to simulant properties and model predictions to confirm the validity of simulant and glass property models work. This report includes results from the three NCAW core samples, comparable results from slurry and glass simulants, and comparisons to glass property model predictions

  5. Influence of Heat Treatment on the Corrosion Behavior of Purified Magnesium and AZ31 Alloy

    OpenAIRE

    Khalifeh, Sohrab; Burleigh, T. David

    2017-01-01

    Magnesium and its alloys are ideal for biodegradable implants due to their biocompatibility and their low-stress shielding. However, they can corrode too rapidly in the biological environment. The objective of this research was to develop heat treatments to slow the corrosion of high purified magnesium and AZ31 alloy in simulated body fluid at 37{\\deg}C. Heat treatments were performed at different temperatures and times. Hydrogen evolution, weight loss, PDP, and EIS methods were used to measu...

  6. Mechanical behaviour of biodegradable AZ31 magnesium alloy after long term in vitro degradation.

    Science.gov (United States)

    Adekanmbi, Isaiah; Mosher, Christopher Z; Lu, Helen H; Riehle, Mathis; Kubba, Haytham; Tanner, K Elizabeth

    2017-08-01

    Biodegradable magnesium alloys including AZ31 are exciting candidates for temporary implants as they eliminate the requirement for surgical removal, yet have higher mechanical properties than degradable polymers. However, the very long term mechanical properties and degradation of these alloys have not been fully characterized. The tensile, bending and corrosion behaviour of biodegradable AZ31 Mg alloy specimens have been investigated for up to 9months in vitro in phosphate buffered saline (PBS). Small AZ31 Mg specimens showed a significant drop in bend yield strength and modulus after 3months in vitro degradation and an average mass loss of 6.1%. Larger dumbbell specimens showed significant drops in tensile strength from 251.96±3.53MPa to 73.5±20.2MPa and to 6.43±0.9MPa and in modulus from 47.8±5.6GPa to 25.01±3.4GPa and 2.36±0.89GPa after 3 and 9months respectively. These reductions were accompanied by an average mass loss of 18.3% in 9months. Degradation rate for the small and large specimens followed similar profiles with immersion time, with peak degradation rates of 0.1747gm -2 h - 1 and 0.0881gm -2 h - 1 , and average rates of 0.1038gm -2 h - 1 and 0.0397gm -2 h - 1 respectively. SEM fractography and polished specimen cross-sections revealed corrosion pits, cracks and corrosion induced defects. These data indicate the potential of AZ31 Mg for use in implants that require medium term degradation with load bearing mechanical properties. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Influence of Zeolite Coating on the Corrosion Resistance of AZ91D Magnesium Alloy

    OpenAIRE

    Banerjee, P. Chakraborty; Woo, Ren Ping; Grayson, Sam Matthew; Majumder, Amrita; Raman, R. K. Singh

    2014-01-01

    The protective performance of zeolite coating on AZ91D magnesium alloy was evaluated using potentiodynamic polarisation and electrochemical impedance spectroscopy (EIS) in 0.1 M sodium chloride solution (NaCl). Electrical equivalent circuit (EEC) was developed based upon hypothetical corrosion mechanisms and simulated to correspond to the experimental data. The morphology and the chemical nature of the coating were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD...

  8. Metallurgical bond between magnesium AZ91 alloy and aluminium plasma sprayed coatings

    Czech Academy of Sciences Publication Activity Database

    Kubatík, Tomáš František; Pala, Zdeněk; Neufuss, Karel; Vilémová, Monika; Mušálek, Radek; Stoulil, J.; Slepička, P.; Chráska, Tomáš

    2015-01-01

    Roč. 282, November (2015), s. 163-170 ISSN 0257-8972 R&D Projects: GA ČR(CZ) GP14-31538P Institutional support: RVO:61389021 Keywords : Plasma spraying * AZ91 magnesium alloy * Aluminium * Metallurgical bond * X-ray diffraction Subject RIV: JK - Corrosion ; Surface Treatment of Materials Impact factor: 2.139, year: 2015 http://www.sciencedirect.com/science/article/pii/S0257897215303297

  9. Effect of ECAP on microstructure and mechanical properties of cast AZ91 magnesium alloy

    International Nuclear Information System (INIS)

    Chung, C W; Gao, W; Ding, R G; Chiu, Y L

    2010-01-01

    An as-cast AZ91 magnesium alloy was processed by Equal Channel Angular Pressing (ECAP) at 320 0 C. The microstructure and mechanical properties were studied. It has been found that ECAP refines both the grains and precipitates, thus modifies the strength and ductility of the processed alloy. After the first pass of ECAP, the yield stress improves significantly from 71 MPa to 140 MPa.

  10. Hydroxyapatite coating on AZ91 magnesium alloy via sol-gel method

    OpenAIRE

    Albayrak, Sevda; Çinici, Hanifi; Çalın, Recep; Cömert, Canser

    2018-01-01

    Producinga material lighter than available biomaterials, having corrosion-resistance tobiological attacks and histocompatible similar to the bone structure in orderto use in biomedical applications is the purpose of this study. Lightness isextremely important in biomedical applications because stainless steel and manyof the similar heavy metallic alloys can lead to infection by causing harm totissues around the implant when it is used in the body. Although the lightnessof AZ91 Mg alloy is an ...

  11. Corrosion characterization of micro-arc oxidization composite electrophoretic coating on AZ31B magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Congjie [School of Materials Science and Engineering, Xi’an University of Technology, Xi’an 710048 (China); Jiang, Bailing [School of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816 (China); Liu, Ming [General Motors China Science Lab, Shanghai 201206 (China); Ge, Yanfeng [School of Materials Science and Engineering, Xi’an University of Technology, Xi’an 710048 (China)

    2015-02-05

    Highlights: • A new protective composite coatings were prepared on AZ31B Mg alloy. • The E-coat locked into MAO coat by discharge channels forming a smoother and compact surface without defects. • Comparing with MAO coat, the MAOE composite coat could provide an excellent barrier for bare Mg against corrosion attack. - Abstract: A two layer composite coating system was applied on the surface of AZ31B magnesium alloy by Micro-arc Oxidation (MAO) plus electrophoretic coat (E-coat) technique. The Mg sample coated with MAO plus E-coat (MAOE) was compared with bare Mg and Mg sample coated by MAO only. The surface microstructure and cross section of bare and coated Mg before and after corrosion were examined by Scanning Electron Microscopy (SEM). The corrosion performance of bare and coated Mg was evaluated using electrochemical measurement and hydrogen evolution test. The results indicated that the corrosion resistance of AZ31B Mg alloy was significantly improved by MAOE composite coating. The corrosion mechanism of bare and coated Mg is discussed.

  12. Nano grained AZ31 alloy achieved by equal channel angular rolling process

    International Nuclear Information System (INIS)

    Hassani, F.Z.; Ketabchi, M.

    2011-01-01

    Equal channel angular rolling (ECAR) is a severe plastic deformation process which is carried out on large, thin sheets. The grain size could be significantly decreased by this process. The main purpose of this study is to investigate the possibility of grain refinement of AZ31 magnesium alloy sheet by this process to nanometer. The effect of the number of ECAR passes on texture evolution of AZ31 magnesium alloy was investigated. ECAR temperature was controlled to maximize the grain refinement efficiency along with preventing cracking. The initial microstructure of as-received AZ31 sheet showed an average grain size of about 21 μm. The amount of grain refinement increased with increasing the pass number. After 10 passes of the process, significant grain refinement occurred and the field emission scanning electron microscopic (FESEM) micrographs showed that the size of grains were decreased significantly to about 14-70 nm. These grains were formed at the grain boundaries and inside some of the previous larger micrometer grains. Observation of optical microstructures and X-ray diffraction patterns (XRD) showed the formation of twins after ECAR process. Micro-hardness of material was studied at room temperature. There was a continuous enhancement of hardness by increasing the pass number of ECAR process. At the 8th pass, hardness values increased by 53%. At final passes hardness reduced slightly, which was attributed to saturation of strain in high number of passes.

  13. Formation and mechanism of nanocrystalline AZ91 powders during HDDR processing

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yafen; Fan, Jianfeng, E-mail: fanjianfeng@tyut.edu.cn; Zhang, Hua; Zhang, Qiang; Gao, Jing; Dong, Hongbiao, E-mail: hd38@leicester.ac.uk; Xu, Bingshe

    2017-03-15

    Grain sizes of AZ91 alloy powders were markedly refined to about 15 nm from 100 to 160 μm by an optimized hydrogenation-disproportionation-desorption-recombination (HDDR) process. The effect of temperature, hydrogen pressure and processing time on phase and microstructure evolution of AZ91 alloy powders during HDDR process was investigated systematically by X-ray diffraction, optical microscopy, scanning electron microscopy and transmission electron microscopy, respectively. The optimal HDDR process for preparing nanocrystalline Mg alloy powders is hydriding at temperature of 350 °C under 4 MPa hydrogen pressure for 12 h and dehydriding at 350 °C for 3 h in vacuum. A modified unreacted core model was introduced to describe the mechanism of grain refinement of during HDDR process. - Highlights: • Grain size of the AZ91 alloy powders was significantly refined from 100 μm to 15 nm. • The optimal HDDR technology for nano Mg alloy powders is obtained. • A modified unreacted core model of grain refinement mechanism was proposed.

  14. Wire Arc Additive Manufacturing of AZ31 Magnesium Alloy: Grain Refinement by Adjusting Pulse Frequency

    Directory of Open Access Journals (Sweden)

    Jing Guo

    2016-10-01

    Full Text Available Wire arc additive manufacturing (WAAM offers a potential approach to fabricate large-scale magnesium alloy components with low cost and high efficiency, although this topic is yet to be reported in literature. In this study, WAAM is preliminarily applied to fabricate AZ31 magnesium. Fully dense AZ31 magnesium alloy components are successfully obtained. Meanwhile, to refine grains and obtain good mechanical properties, the effects of pulse frequency (1, 2, 5, 10, 100, and 500 Hz on the macrostructure, microstructure and tensile properties are investigated. The results indicate that pulse frequency can result in the change of weld pool oscillations and cooling rate. This further leads to the change of the grain size, grain shape, as well as the tensile properties. Meanwhile, due to the resonance of the weld pool at 5 Hz and 10 Hz, the samples have poor geometry accuracy but contain finer equiaxed grains (21 μm and exhibit higher ultimate tensile strength (260 MPa and yield strength (102 MPa, which are similar to those of the forged AZ31 alloy. Moreover, the elongation of all samples is above 23%.

  15. Study on fluidity of squeeze cast AZ91D magnesium alloy with different wall thicknesses

    Directory of Open Access Journals (Sweden)

    Chen Yun

    2014-03-01

    Full Text Available Rectangular cross-section specimens with different section thicknesses were prepared to study the influences of pouring temperature, mould temperature and squeeze velocity on the fluidity of squeeze cast AZ91D magnesium alloy by means of orthogonal test design method. The results show that pouring temperature, mould temperature and squeeze velocity can significantly affect the fluidity of magnesium alloy specimens with wall thickness no more than 4 mm, and the pouring temperature is the most influential factor on the fluidity of specimens with wall thickness of 1, 2 and 3 mm, while mould temperature is the one for specimens with wall thickness of 4 mm. Increasing pouring temperature between 700 °C and 750 °C is beneficial to the fluidity of AZ91D magnesium alloy, and increasing mould temperature significantly enhances the filling ability of thick (3 and 4 mm section castings. The fluidity of squeeze cast magnesium alloy increases with the increase of wall thickness. It is not recommended to produce magnesium alloy casting with wall thickness of smaller than 3 mm by squeeze cast process due to the poor fluidity. The software DPS was used to generate the regression model, and linear regression equations of the fluidity of squeeze cast AZ91D with different wall thicknesses are obtained using the test results.

  16. The effect of PVD coatings on the corrosion behaviour of AZ91 magnesium alloy

    International Nuclear Information System (INIS)

    Altun, Hikmet; Sen, Sadri

    2006-01-01

    In this study, multilayered AlN (AlN + AlN + AlN) and AlN + TiN were coated on AZ91 magnesium alloy using physical vapour deposition (PVD) technique of DC magnetron sputtering, and the influence of the coatings on the corrosion behaviour of the AZ91 alloy was examined. A PVD system for coating processes, a potentiostat for electrochemical corrosion tests, X-ray difractometer for compositional analysis of the coatings, and scanning electron microscopy for surface examinations were used. It was determined that PVD coatings deposited on AZ91 magnesium alloy increased the corrosion resistance of the alloy, and AlN + AlN + AlN coating increased the corrosion resistance much more than AlN + TiN coating. However, it was observed that, in the coating layers, small structural defects e.g., pores, pinholes, cracks that could arise from the coating process or substrate and get the ability of protection from corrosion worsened were present

  17. Cerium Addition Improved the Dry Sliding Wear Resistance of Surface Welding AZ91 Alloy

    Directory of Open Access Journals (Sweden)

    Qingqiang Chen

    2018-02-01

    Full Text Available In this study, the effects of cerium (Ce addition on the friction and wear properties of surface welding AZ91 magnesium alloys were evaluated by pin-on-disk dry sliding friction and wear tests at normal temperature. The results show that both the friction coefficient and wear rate of surfacing magnesium alloys decreased with the decrease in load and increase in sliding speed. The surfacing AZ91 alloy with 1.5% Ce had the lowest friction coefficient and wear rate. The alloy without Ce had the worst wear resistance, mainly because it contained a lot of irregularly shaped and coarse β-Mg17Al12 phases. During friction, the β phase readily caused stress concentration and thus formed cracks at the interface between β phase and α-Mg matrix. The addition of Ce reduced the size and amount of Mg17Al12, while generating Al4Ce phase with a higher thermal stability. The Al-Ce phase could hinder the grain-boundary sliding and migration and reduced the degree of plastic deformation of subsurface metal. Scanning electron microscopy observation showed that the surfacing AZ91 alloy with 1.5% Ce had a total of four types of wear mechanism: abrasion, oxidation, and severe plastic deformation were the primary mechanisms; delamination was the secondary mechanism.

  18. Electrodeposition of Al-Mn alloy on AZ31B magnesium alloy in molten salts

    International Nuclear Information System (INIS)

    Zhang Jifu; Yan Chuanwei; Wang Fuhui

    2009-01-01

    The Al-Mn alloy coatings were electrodeposited on AZ31B Mg alloy in AlCl 3 -NaCl-KCl-MnCl 2 molten salts at 170 deg. C aiming to improve the corrosion resistance. However, in order to prevent AZ31B Mg alloy from corrosion during electrodeposition in molten salts and to ensure excellent adhesion of coatings to the substrate, AZ31B Mg alloy should be pre-plated with a thin zinc layer as intermediate layer. Then the microstructure, composition and phase constituents of the coatings were investigated by scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDX), and X-ray diffraction (XRD). It was indicated that, by adjusting the MnCl 2 content in the molten salts from 0.5 wt% to 2 wt%, the Mn content in the alloy coating was increased and the phase constituents were changed from f.c.c Al-Mn solid solution to amorphous phase. The corrosion resistance of the coatings was evaluated by potentiodynamic polarization measurements in 3.5% NaCl solution. It was confirmed that the Al-Mn alloy coatings exhibited good corrosion resistance with a chear passive region and significantly reduced corrosion current density at anodic potentiodynamic polarization. The corrosion resistance of the alloy coatings was also related with the microstructure and Mn content of the coatings.

  19. Characteristics of AZ31 Mg alloy joint using automatic TIG welding

    Science.gov (United States)

    Liu, Hong-tao; Zhou, Ji-xue; Zhao, Dong-qing; Liu, Yun-teng; Wu, Jian-hua; Yang, Yuan-sheng; Ma, Bai-chang; Zhuang, Hai-hua

    2017-01-01

    The automatic tungsten-inert gas welding (ATIGW) of AZ31 Mg alloys was performed using a six-axis robot. The evolution of the microstructure and texture of the AZ31 auto-welded joints was studied by optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and electron backscatter diffraction. The ATIGW process resulted in coarse recrystallized grains in the heat affected zone (HAZ) and epitaxial growth of columnar grains in the fusion zone (FZ). Substantial changes of texture between the base material (BM) and the FZ were detected. The {0002} basal plane in the BM was largely parallel to the sheet rolling plane, whereas the c-axis of the crystal lattice in the FZ inclined approximately 25° with respect to the welding direction. The maximum pole density increased from 9.45 in the BM to 12.9 in the FZ. The microhardness distribution, tensile properties, and fracture features of the AZ31 auto-welded joints were also investigated.

  20. Stamping of Thin-Walled Structural Components with Magnesium Alloy AZ31 Sheets

    International Nuclear Information System (INIS)

    Chen, F.-K.; Chang, C.-K.

    2005-01-01

    In the present study, the stamping process for manufacturing cell phone cases with magnesium alloy AZ31 sheets was studied using both the experimental approach and the finite element analysis. In order to determine the proper forming temperature and set up a fracture criterion, tensile tests and forming limit tests were first conducted to obtain the mechanical behaviors of AZ31 sheets at various elevated temperatures. The mechanical properties of Z31 sheets obtained from the experiments were then adopted in the finite element analysis to investigate the effects of the process parameters on the formability of the stamping process of cell phone cases. The finite element simulation results revealed that both the fracture and wrinkle defects could not be eliminated at the same time by adjusting blank-holder force or blank size. A drawbead design was then performed using the finite element simulations to determine the size and the location of drawbead required to suppress the wrinkle defect. An optimum stamping process, including die geometry, forming temperature, and blank dimension, was then determined for manufacturing the cell phone cases. The finite element analysis was validated by the good agreement between the simulation results and the experimental data. It confirms that the cell phone cases can be produced with magnesium alloy AZ31 sheet by the stamping process at elevated temperatures

  1. Precipitation behavior and effect of new precipitated β phase in AZ80 magnesium alloy

    Institute of Scientific and Technical Information of China (English)

    TANG Wei; HAN En-hou; XU Yong-bo; LIU Lu

    2006-01-01

    Granular precipitate that was a new kind of β-Mg17Al12 phase found in aged AZ80 wrought Mg alloy at all aging temperature was studied. The structure and precipitation behavior of this granular β-Mg17Al12 precipitate were studied by environmental scanning electron microscopy (ESEM) and transmission electron microscopy (TEM). The effect of the granular precipitate on mechanical properties of AZ80 alloy was also studied. The new precipitate that was granular and nucleated both on grain boundaries (GBs) and twin boundaries, has the same crystal structure and lattice parameter as those of the continuous or discontinuous precipitated β-Mg17Al12. And the nucleation and growth of the granular precipitate are faster than those of the other two precipitates at higher temperatures (above 583 K), but are suppressed at lower temperatures (below 423 K). At lower temperatures, the discontinuous β-Mg17Al12 precipitates firstly and the granular β-Mg17Al12 precipitates after aged more than 40 h. The crack is easily nucleated on the phase boundaries of granular phase and matrix because of the weak binding force. As a result, the strength and ductility of AZ80 Mg alloy are decreased by the granular β-Mg17Al12 precipitate.

  2. Influence of heat treatment on the machinability and corrosion behavior of AZ91 Mg alloy

    Directory of Open Access Journals (Sweden)

    Swetha Chowdary V

    2018-03-01

    Full Text Available In the present study, AZ91 Mg alloy was heat treated at 410 °C for 6, 12 and 24 h to investigate the influence of heat treatment on machinability and corrosion behavior. The effect of soaking time on the amount and distribution of Mg17Al12 (β – phase was analyzed under the optical microscope. Microhardness measurements demonstrated the increased hardness with increased heat treatment soaking time, which can be attributed to the solid solution strengthening. The influence of super saturated α-grains on reducing the cutting force (Fz with respect to increased cutting speed was observed as prominent. The corrosion behavior of the heat treated specimens was studied by conducting electrochemical tests. Surprisingly, corrosion rate of heat treated samples was observed as increased compared with the base material. From the results, it is evident that the machinability of AZ91 Mg alloy can be improved by producing super saturated α-grains through heat treatment but at the cost of losing corrosion resistance. Keywords: AZ91 Mg alloy, Solid solution, Turning, Corrosion, Machinability

  3. Corrosion of AZ91D magnesium alloy with a chemical conversion coating and electroless nickel layer

    International Nuclear Information System (INIS)

    Huo Hongwei; Li Ying; Wang Fuhui

    2004-01-01

    A chemical conversion treatment and an electroless nickel plating were applied to AZ91D alloy to improve its corrosion resistance. By conversion treatment in alkaline stannate solution, the corrosion resistance of the alloy was improved to some extent as verified by immersion test and potentiodynamic polarization test in 3.5 wt.% NaCl solution at pH 7.0. X-ray diffraction patterns of the stannate treated AZ91D alloy showed the presence of MgSnO 3 · H 2 O, and SEM images indicated a porous structure, which provided advantage for the adsorption during sensitisation treatment prior to electroless nickel plating. A nickel coating with high phosphorus content was successfully deposited on the chemical conversion coating pre-applied to AZ91D alloy. The presence of the conversion coating between the nickel coating and the substrate reduced the potential difference between them and enhanced the corrosion resistance of the alloy. An obvious passivation occurred for the nickel coating during anodic polarization in 3.5 wt.% NaCl solution

  4. Flow behaviour of magnesium alloy AZ31B processed by equal-channel angular pressing

    International Nuclear Information System (INIS)

    Arun, M S; Chakkingal, U

    2014-01-01

    Magnesium alloys are characterised by their low density, high specific strength and stiffness. But, the potential application of Mg is limited by its low room-temperature ductility and formability. Formability can be improved by developing an ultrafine grained (UFG) structure. Equal channel angular pressing (ECAP) is a well known process that can be used to develop an ultrafine grained microstructure. The aim of this study was to investigate the flow behaviour of AZ31B magnesium alloy after ECAP. The specimen was subjected to three passes of ECAP with a die angle of 120° using processing route Bc. The processing temperature was 523 K for the first pass and 423 K for the subsequent two passes. The microstructure characterisation was done. Compression tests of ECAPed and annealed specimens were carried out at strain rates of 0.01 – 1s −1 and deformation temperatures of 200 – 300°C using computer servo-controlled Gleeble-3800 system. The value of activation energy Q and the empirical materials constants of A and n were determined. The equations relating flow stress and Zener-Hollomon parameter were proposed. In the case annealed AZ31, the activation energy was determined to be 154 kJ/mol, which was slightly higher than the activation energy of 144 kJ/mol for ECAPed AZ31

  5. Flow behaviour of magnesium alloy AZ31B processed by equal-channel angular pressing

    Science.gov (United States)

    Arun, M. S.; Chakkingal, U.

    2014-08-01

    Magnesium alloys are characterised by their low density, high specific strength and stiffness. But, the potential application of Mg is limited by its low room-temperature ductility & formability. Formability can be improved by developing an ultrafine grained (UFG) structure. Equal channel angular pressing (ECAP) is a well known process that can be used to develop an ultrafine grained microstructure. The aim of this study was to investigate the flow behaviour of AZ31B magnesium alloy after ECAP. The specimen was subjected to three passes of ECAP with a die angle of 120° using processing route Bc. The processing temperature was 523 K for the first pass and 423 K for the subsequent two passes. The microstructure characterisation was done. Compression tests of ECAPed and annealed specimens were carried out at strain rates of 0.01 - 1s-1 and deformation temperatures of 200 - 300°C using computer servo-controlled Gleeble-3800 system. The value of activation energy Q and the empirical materials constants of A and n were determined. The equations relating flow stress and Zener-Hollomon parameter were proposed. In the case annealed AZ31, the activation energy was determined to be 154 kJ/mol, which was slightly higher than the activation energy of 144 kJ/mol for ECAPed AZ31.

  6. Dry Sliding Wear Charactristics of Aluminum 6061-T6, Magnesium AZ31 and Rock Dust Composite

    Science.gov (United States)

    Balachandar, R.; Balasundaram, R.; Rajkumar, G.

    2018-02-01

    In recent years, the use of aluminum composite is gaining popularity in a wide range of applications like automobiles, aerospace and constructions (both interior & exterior) panels etc., due to its high strength, low density characteristics. Various reinforcing materials are used with aluminum 6061-T6 in order to have better mechanical properties. The addition of 0.3% of magnesium AZ31 will increase the ultimate tensile strength by 25 %. The reinforcement of rock dust will decrease the density. Hence, in order to have an advantages of magnesium AZ31 and rock dust, in this work, these two constitutes are varied from 1% to 2% on the base material of Al6061-T6 in stir casting. To evaluate the wear characteristics, Pin on disc is used in these composites. The input parameters are speed, time & load. The output response is wear. To minimize the number of experiments, L9 orthogonal array is used. The test results showed that a composite of 97% of Al (6061-T6), 1% Mg (AZ31) & 2 % of rock dust produced less wear. To find the best value of operating parameter for each sample, ANN-GA is used.

  7. Enrique Díaz and Present Phpotographies (From Graphic Notes to Photo-essays

    Directory of Open Access Journals (Sweden)

    Rebeca Monroy Nasr

    1998-10-01

    Full Text Available With "Enrique Díaz and Present Phpotographies (From Graphic Notes to Photo-essays ", the author presents part of our photo­graphic history, as well as some aspects of its development as a form of journalism and of art. She rescues the figure of Enrique Díaz Reyna as representative of the union of graphic journalists, due to his technical, formal and conceptual traits, all of them tools with which he opened important paths and innovative graphical and aesthetic proposals. This essay presents some aspects of the graphic journalist's work in Mexico City, from the twenties to the forties. As a guide to the photographer's extensi­ve work, the author reviews some of the proposals he made as his work became more mature: first, the graphic note, later, recrea­ting the photo-reportage, and finally, exploring with photoessays. Thus, attention is centered particularly on Díaz Reyna's visual language, where the signs of a distinctive modernity appro­priate of his time allow us to understand a substantial part of the transition towards a contemporary and  truly national photo-journalism.

  8. RANCANG BANGUN GAME ALGORITMA DAN STRUKTUR DATA BERBASIS ROLE PLAYING GAME (RPG SEBAGAI MEDIA PEMBELAJARAN MAHASISWA TEKNIK INFORMATIKA UNIVERSITAS MUHAMMADIYAH SIDOARJO

    Directory of Open Access Journals (Sweden)

    Cindy Taurusta

    2017-07-01

    Full Text Available Berdasarkan hasil survey yang dilakukan peneliti pada Mahasiswa/i Teknik Informatika semester 5 sebanyak 41.9% dan semester 7 sebanyak 24.2%, diperoleh hasil bahwa dari beberapa pelajaran pemrograman dasar di Jurusan Teknik Informatika, mata kuliah Algortima dan Struktur Data lah yang memiliki prosentasi tingkat kepahaman paling rendah yaitu 11.5% dan tingkat kesukaan/minat hanya 8.2%. Maka dari itu peneliti membuat Rancang Bangun Game Algoritma dan Struktur Data Berbasis Role Playing Game (RPG Sebagai Media Pembelajaran Mahasiswa Teknik Informatika Universitas Muhammadiyah Sidoarjo. mayoritas mahasiswa lebih suka bermain game sambil mengungkapkan misi yaitu sebesar 85,7%. Dan didapat bahwa sebesar 61,9% koresponden mengatakan bahwa game Algoritma dan Struktru Data “Fun with ALGOS” ini sudah dapat dikatakan sangat efektif, bagus, dan menyenangkan. Sedangkan hasil apakah game ini perlu diterapkan dalam metode pengajaran Algoritma dan Struktur Data, didapat sebesar 66,7% mahasiswa mendukung metode ini diterapkan di seluruh Universitas. Sedangkan dari sisi Ahli Materi, sebesar 100% mengatakan bahwa perlu ada metode pengajaran baru. Dan ketika peneliti menanyakan apakah metode pembelajaran baru itu berupa game, maka kedua ahli meteri tersebut juga seluruhnya yaitu 100% mengatakan setuju, karena memberikan warna baru dalam dunia pengajaran. Namun untuk materinya sendiri masih kurang sesuai penyampaiaan dalam setiap misinya, maka perlu ditingkatkan kepahaman materi dengan misi yang harus diselesaikan pemain. Dari segi ahli media sendiri mengatakan bahwa sebesar 100% mengatakan bahwa game ini menarik untuk dimainkan begitupun dari segi storyboard-nya. Namun dari segi grafisnya seluruh ahli media yaitu 100% mengatakan cukup menarik dan dari segi karakternya masih kurang dan monoton. Sedangkan dari segi ketertarikan seluruh aspek koresponden mulai dari mahasiswa, ahli materi, dan ahli media terdapat rata – rata 3.67 (sangat baik yang membuktikan

  9. Pemetaan Potensi Kekeringan Lahan se-pulau Batam menggunakan Teknik Sistem Informasi Geografis (SIG dan Penginderaan Jauh

    Directory of Open Access Journals (Sweden)

    Titi Aprilliyanti

    2017-04-01

    Full Text Available Kekeringan merupakan hubungan antara ketersediaan air yang jauh dibawah kebutuhan baik untuk kebutuhan hidup, pertanian, kegiatan ekonomi dan lingkungan. Informasi mengenai potensi kekeringan sangat diperlukan untuk pencegahan ataupun penanggulangan untuk mengurangi dampak negatif yang ditimbulkan. Adapun tujuan dari penelitian ini adalah menghasilkan peta potensi kekeringan lahan di Batam yang berbasis web. Dalam penelitian ini memanfaatkan teknik penginderaan jauh dan SIG. Penggunaan citra landsat 8 untuk menentukan nilai LST (Land Surface Temperature dan penggunaan lahan kemudian di overlay dan dilakukan scoring. Tahap akhir penelitian yaitu melakukan validasi terhadap parameter-parameter yang mempengaruhi dengan mengambil beberapa sampel. Adapun hasil akhir dari penelitian ini adalah peta potensi kekeringan se-pulau Batam yang memiliki 5 kelas potensi kekeringan. Kelas potensi kekeringan sangat rendah dengan  luas area 2629.45 ha yang dominan terletak pada Kecamatan Sungai Beduk, Sekupang dan Batu Aji. Kelas potensi kekeringan rendah dengan luas area 9585.521 ha yang dominan terletak pada Kecamatan Sekupang. Kelas potensi kekeringan sedang dengan  luas area 9507.12 ha yang dominan terletak pada Kecamatan Sekupang. Kelas potensi kekeringan tinggi dengan  luas area 7081.392 ha yang dominan terletak pada Kecamatan Sekupang, Sagulung dan Nongsa. Kelas potensi kekeringan sangat tinggi dengan luas area 15600.12 ha yang dominan terletak pada Kecamatan Batam Kota dan Nongsa.   Drought is the relationship between the availability of water is far below the need both for the necessities of life, agriculture, economic activities and the environment. Information about potential droughts is indispensable for the prevention or mitigation to reduce the negative impact caused. As for the purpose of this research is to produce a map of potential drought land in the Batam-based web. In this research utilising remote sensing and GIS techniques. The use of

  10. Tank 241-AZ-102 Privatization Push Mode Core Sampling and Analysis Plan

    International Nuclear Information System (INIS)

    RASMUSSEN, J.H.

    1999-01-01

    This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for samples obtained from tank 241-AZ-102. The purpose of this sampling event is to obtain information about the characteristics of the contents of 241-AZ-102 required to satisfy the Data Quality Objectives For TWRS Privatization Phase I : Confirm Tank TIS An Appropriate Feed Source For High-Level Waste Feed Batch X(HLW DQO) (Nguyen 1999a), Data Quality Objectives For TWRS Privatization Phase 1: Confirm Tank TIS An Appropriate Feed Source For Low-Activity Waste Feed Batch X (LAW DQO) (Nguyen 1999b), Low Activity Waste and High Level Waste Feed Data Quality Objectives (L and H DQO) (Patello et al. 1999) and Characterization Data Needs for Development, Design, and Operation of Retrieval Equipment Developed through the Data Quality Objective Process (Equipment DQO) (Bloom 1996). The Tank Characterization Technical Sampling Basis document (Brown et al. 1998) indicates that these issues, except the Equipment DQO apply to tank 241-AZ-102 for this sampling event. The Equipment DQO is applied for shear strength measurements of the solids segments only. Poppiti (1999) requires additional americium-241 analyses of the sludge segments. Brown et al. (1998) also identify safety screening, regulatory issues and provision of samples to the Privatization Contractor(s) as applicable issues for this tank. However, these issues will not be addressed via this sampling event. Reynolds et al. (1999) concluded that information from previous sampling events was sufficient to satisfy the safety screening requirements for tank 241-AZ-102. Push mode core samples will be obtained from risers 15C and 24A to provide sufficient material for the chemical analyses and tests required to satisfy these data quality objectives. The 222-S Laboratory will extrude core samples, composite the liquids and solids, perform chemical analyses

  11. Lactancia materna, alimentación artificial y el primer contacto con azúcar

    Directory of Open Access Journals (Sweden)

    Fabian Calixto Fraiz

    2013-01-01

    Full Text Available Objetivo: Este estudio evaluó los cambios en el patrón de lactancia materna, alimentación artificial y en la introducción de azúcar en la dieta de niños de 0 a 36 meses, a través de dos estudios, con un intervalo de 13 años en la ciudad de Curitiba, Paraná, Brasil. Material y métodos: Poblaciones semejantes de una misma región geográfica fueron evaluadas a través de un cuestionario, en los años de 1993 y 2006, envolviendo, respectivamente, las madres de 180 y 94 niños. Introducción de azúcar en la dieta fue considerada precoz cuando ocurrió antes del 6º mes completo de vida. Los datos fueron analizados estadísticamente a través del test de qui-cuadrado y test exacto de Fisher (α= 0,05. Resultados: Hubo diferencias en la frecuencia del primer contacto con azúcar (p <0,001, que ocurrió en el primer mes de vida en 61,7% de los niños del primer estudio y en sólo 3,2% de los niños del segundo estudio. Hubo diferencias en el patrón de lactancia materna (p = 0,02, siendo la prevalencia de niños amamantados mayor en el segundo estudio. No fueron encontradas diferencias estadísticamente significativas en la prevalencia de uso de biberón, uso de biberón durante la noche y lactancia materna durante la noche, así como en el uso de biberón conteniendo azúcar. Conclusiones: Estos resultados indican que la lactancia materna puede, además de sus varias ventajas, también promover el aplazamiento de la introducción de azúcar en la dieta infantil. Nuevas investigaciones son necesarias para confirmar esta hipótesis.

  12. Effectiveness of Ti-micro alloying in relation to cooling rate on corrosion of AZ91 Mg alloy

    International Nuclear Information System (INIS)

    Candan, S.; Celik, M.; Candan, E.

    2016-01-01

    In this study, micro Ti-alloyed AZ91 Mg alloys (AZ91 + 0.5wt.%Ti) have been investigated in order to clarify effectiveness of micro alloying and/or cooling rate on their corrosion properties. Molten alloys were solidified under various cooling rates by using four stage step mold. The microstructural investigations were carried out by using scanning electron microscopy (SEM). Corrosion behaviors of the alloys were evaluated by means of immersion and electrochemical polarization tests in 3.5% NaCl solution. Results showed that the Mg 17 Al 12 (β) intermetallic phase in the microstructure of AZ91 Mg alloy formed as a net-like structure. The Ti addition has reduced the distribution and continuity of β intermetallic phase and its morphology has emerged as fully divorced eutectic. Compared to AZ91 alloy, the effect of the cooling rate in Ti-added alloy on the grain size was less pronounced. When AZ91 and its Ti-added alloys were compared under the same cooling conditions, the Ti addition showed notably high corrosion resistance. Electrochemical test results showed that while I corr values of AZ91 decrease with the increase in the cooling rate, the effect of the cooling rate on I corr values was much lower in the Ti-added alloy. The corrosion resistance of AZ91 Mg alloy was sensitive towards the cooling rates while Ti-added alloy was not affected much from the cooling conditions. - Highlights: • Effect the cooling rate on grain size was less pronounced in the Ti-added alloy. • The morphology of the β phase transformed into fully divorced eutectics. • Ti addition exhibited significantly higher corrosion resistance. • Ti micro alloying is more effective than faster cooling of the alloy on corrosion.

  13. The study of a Mg-rich epoxy primer for protection of AZ91D magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Lu Xiangyu [School of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Zuo Yu, E-mail: zuoy@mail.buct.edu.c [School of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Zhao Xuhui; Tang Yuming; Feng Xingguo [School of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing 100029 (China)

    2011-01-15

    Research highlights: {yields} A Mg-rich epoxy primer was prepared by adding pure magnesium particles in epoxy coating. Cross scratch testing results showed that in 3% NaCl solution the Mg-rich primer showed better protection for AZ91D magnesium alloy than the same epoxy primer without Mg addition. {yields} The open circuit potential of AZ91D alloy in NaCl solution decreased after coated with Mg-rich coating, suggesting that cathodic protection effect of the Mg-rich coating on AZ91D alloy was present. {yields} EIS studies showed that during the immersion tests of AZ91D alloy with Mg-rich coating the magnesium particles in coating dissolved with the charge-transfer resistance R{sub ct} at the magnesium particle/coating interface decreased and the double-layer capacitance Q{sub dl} increased. While the coating resistance remained stable for a long time and corrosion of the AZ91D alloy substrate was obviously delayed. - Abstract: A Mg-rich epoxy primer was prepared by adding pure magnesium particles to an epoxy coating. The coating properties were studied with electrochemical impedance spectroscopy (EIS), scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The Mg-rich primer showed better protection for AZ91D magnesium alloy than the same epoxy primer without Mg addition. The open circuit potential measurements showed cathodic protection effect of the Mg-rich primer on AZ91D alloy. Cross scratch testing showed that the Mg-rich primer provided better protection for the substrate than original epoxy coating. The precipitation of Mg(OH){sub 2} in the coating also provided some degree of barrier protection.

  14. Effects of sintering temperature on the corrosion behavior of AZ31 alloy with Ca–P sol–gel coating

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Bo [School of Materials Science and Engineering, Liaoning University of Technology, Jinzhou, Liaoning Province, 121001 (China); Shi, Ping, E-mail: p_shi@sohu.com [School of Materials Science and Engineering, Liaoning University of Technology, Jinzhou, Liaoning Province, 121001 (China); Wei, Donghua [School of Materials Science and Engineering, Liaoning University of Technology, Jinzhou, Liaoning Province, 121001 (China); E, Shanshan [School of Mathematics and Physics, Bohai University, Jinzhou, Liaoning Province, 121013 (China); Li, Qiang; Chen, Yang [School of Materials Science and Engineering, Liaoning University of Technology, Jinzhou, Liaoning Province, 121001 (China)

    2016-04-25

    To slow down the initial biodegradation rate of magnesium alloy, calcium phosphate (Ca–P) coatings were prepared on AZ31 magnesium alloy by a sol–gel technique. To study the effects of sintering temperature on microstructure, bonding strength and corrosion behavior of the coatings, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and an adhesive strength test were used to characterize the coatings. The corrosion resistance of the coatings was investigated by immersion test and electrochemical corrosion techniques in simulated body fluid (SBF) solution. It shows that the sol–gel coatings consist of Ca{sub 2}P{sub 2}O{sub 7}, mixture of Ca{sub 2}P{sub 2}O{sub 7}, Ca{sub 3}(PO{sub 4}){sub 2} and hydroxyapatite, and hydroxyapatite, by sintering respectively at 300 °C, 400 °C and 500 °C. There are major cracks on the coatings. The crack area portion on the coating and the bonding strength at the interface between the calcium phosphate coating and the bare AZ31 increases, and the corrosion resistance of the coated AZ31 in SBF decreases with increasing sintering temperatures from 300 °C to 500 °C. Based on our investigations, the corrosion resistance of the coated AZ31 in SBF depends mainly on the crack area portion on the coatings, rather than on the coating phase stability. - Highlights: • Ca–P coating was prepared on AZ31 alloy by a sol–gel technique. • Crack area portion in the coating increases with temperatures. • Bonding strength between Ca–P coating and substrate increases with temperatures. • Corrosion resistance of the coated AZ31 in SBF decreases with temperatures. • Corrosion resistance of the coated AZ31 depends mainly on the crack area portion.

  15. The study of a Mg-rich epoxy primer for protection of AZ91D magnesium alloy

    International Nuclear Information System (INIS)

    Lu Xiangyu; Zuo Yu; Zhao Xuhui; Tang Yuming; Feng Xingguo

    2011-01-01

    Research highlights: → A Mg-rich epoxy primer was prepared by adding pure magnesium particles in epoxy coating. Cross scratch testing results showed that in 3% NaCl solution the Mg-rich primer showed better protection for AZ91D magnesium alloy than the same epoxy primer without Mg addition. → The open circuit potential of AZ91D alloy in NaCl solution decreased after coated with Mg-rich coating, suggesting that cathodic protection effect of the Mg-rich coating on AZ91D alloy was present. → EIS studies showed that during the immersion tests of AZ91D alloy with Mg-rich coating the magnesium particles in coating dissolved with the charge-transfer resistance R ct at the magnesium particle/coating interface decreased and the double-layer capacitance Q dl increased. While the coating resistance remained stable for a long time and corrosion of the AZ91D alloy substrate was obviously delayed. - Abstract: A Mg-rich epoxy primer was prepared by adding pure magnesium particles to an epoxy coating. The coating properties were studied with electrochemical impedance spectroscopy (EIS), scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The Mg-rich primer showed better protection for AZ91D magnesium alloy than the same epoxy primer without Mg addition. The open circuit potential measurements showed cathodic protection effect of the Mg-rich primer on AZ91D alloy. Cross scratch testing showed that the Mg-rich primer provided better protection for the substrate than original epoxy coating. The precipitation of Mg(OH) 2 in the coating also provided some degree of barrier protection.

  16. The Effects of Rare Earth Pr and Heat Treatment on the Wear Properties of AZ91 Alloy

    Directory of Open Access Journals (Sweden)

    Ning Li

    2018-06-01

    Full Text Available This paper investigated the influences of Pr addition and heat treatment (T6 on the dry sliding wear behavior of AZ91 alloy. The wear rates and friction coefficients were measured by using a pin-on-disc tribometer under loads of 30, 60 and 90 N at dry sliding speeds of 100 rpm, over a sliding time of 15 min. The worn surfaces were examined using a scanning electron microscope and was analyzed with an energy dispersive spectrometer. The experimental results revealed that AZ91-1.0%Pr magnesium alloy exhibited lower wear rate and friction coefficient than the other investigated alloys. As the applied load increased, the wear rate and friction coefficient increased. Compared with the as-cast AZ91-1.0%Pr magnesium alloy, the hardness and wear resistance of the alloy after solution treatment were reduced, and through the subsequent aging, the hardness and wear resistance of the alloy were improved and the hardness was 101.1 HB (compared to as-cast AZ91 magnesium alloy, it increased by 45%. The AZ91-1.0%Pr with T6 magnesium alloy exhibited best wear resistance. Abrasion was dominant at load of 30 N, delamination was dominant at load of 60 N and plastic deformation was dominant at load of 90 N. Oxidation was observed at all loads.

  17. Effect of thermal tempering on microstructure and mechanical properties of Mg-AZ31/Al-6061 diffusion bonding

    Energy Technology Data Exchange (ETDEWEB)

    Jafarian, Mojtaba [Young Researchers and Elite Club, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Rizi, Mohsen Saboktakin, E-mail: M.saboktakin@Pa.iut.ac.ir [Department of Materials Engineering, Isfahan University of Technology, Isfahan 8415683111 (Iran, Islamic Republic of); Department of Industrial Engineering, Lenjan Branch, Islamic Azad University, Isfahan (Iran, Islamic Republic of); Jafarian, Morteza [Young Researchers and Elite Club, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Honarmand, Mehrdad [Department of Mechanical Engineering, Tiran Branch, Islamic Azad University, Isfahan (Iran, Islamic Republic of); Javadinejad, Hamid Reza; Ghaheri, Ali [Department of Materials Engineering, Isfahan University of Technology, Isfahan 8415683111 (Iran, Islamic Republic of); Department of Industrial Engineering, Lenjan Branch, Islamic Azad University, Isfahan (Iran, Islamic Republic of); Bahramipour, Mohammad Taghi [Materials Engineering Department, Hakim Sabzevari University, Sabzevar, 397 (Iran, Islamic Republic of); Ebrahimian, Marzieh [Department of Materials Engineering, Isfahan University of Technology, Isfahan 8415683111 (Iran, Islamic Republic of); Department of Industrial Engineering, Lenjan Branch, Islamic Azad University, Isfahan (Iran, Islamic Republic of)

    2016-06-01

    The objective of this study is to investigate the effect of the types thermal tempering of aluminum alloy on microstructure and mechanical properties of AZ31-O Mg and Al 6061-T6 diffusion bonding. Using Optical Microscope (OM) and Scanning Electron Microscopes (SEM) equipped with EDS analysis and line scan the interfaces of joints were evaluated. The XRD analysis was carried out to characterize phase constitution near the interface zone. The mechanical properties of joints were measured using Vickers micro-hardness and shear strength. According to the results in bonding of AZ31-Mg/Al-6061-O, in less plastic deformation in magnesium alloy, diffusion rate of most magnesium atoms occurred to aluminum alloy and formation of diffusion zone with minimum micro-hardness (140 HV) and maximum shear strength (32 MPa) compared to Al 6061-T6/Mg-AZ31 bonding. Evaluation of fracture surfaces indicates an occurrence of failure from the brittle intermetallic phases. - Highlights: • Diffusion bonding AZ31 to Al-6061withoutany interlayer was successful. • Thermal tempered aluminum alloy plays a vital role in the mechanical properties of joint. • Less thickness of reaction layers and micro-hardness in bonding annealed Al- 6061 layers to AZ31 was achieved. • Fracture surfaces indicated that the onset of fracture from intermetallic compounds resulted in fracture of the cleavage.

  18. A biodegradable AZ91 magnesium alloy coated with a thin nanostructured hydroxyapatite for improving the corrosion resistance

    Energy Technology Data Exchange (ETDEWEB)

    Mukhametkaliyev, T.M.; Surmeneva, M.A. [National Research Tomsk Polytechnic University, 634050, Lenin Avenue 43, Tomsk (Russian Federation); Vladescu, A. [National Research Tomsk Polytechnic University, 634050, Lenin Avenue 43, Tomsk (Russian Federation); National Institute for Optoelectronics, 409 Atomistilor St., RO77125 Magurele (Romania); Cotrut, C.M. [National Research Tomsk Polytechnic University, 634050, Lenin Avenue 43, Tomsk (Russian Federation); Politehnica University of Bucharest, 313 Spl. Independentei, Bucharest (Romania); Braic, M.; Dinu, M. [National Institute for Optoelectronics, 409 Atomistilor St., RO77125 Magurele (Romania); Vranceanu, M.D. [Politehnica University of Bucharest, 313 Spl. Independentei, Bucharest (Romania); Pana, I. [National Institute for Optoelectronics, 409 Atomistilor St., RO77125 Magurele (Romania); Faculty of Physics, Bucharest University, 405 Atomistilor St., RO77125 Magurele (Romania); Mueller, M. [Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB, 70569 Stuttgart (Germany); Surmenev, R.A., E-mail: rsurmenev@gmail.com [National Research Tomsk Polytechnic University, 634050, Lenin Avenue 43, Tomsk (Russian Federation)

    2017-06-01

    The main aim of this study was to investigate the properties of an AZ91 alloy coated with nanostructured hydroxyapatite (HA) prepared by radio frequency (RF) magnetron sputtering. The bioactivity and biomineralization of the AZ91 magnesium alloy coated with HA were investigated in simulated body fluid (SBF) via an in vitro test. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) analyses were performed. The samples were immersed in SBF to study the ability of the surface to promote the formation of an apatite layer as well as corrosion resistance and mass change of the HA-coated AZ91 alloy. Electrochemical tests were performed to estimate the corrosion behaviour of HA-coated and uncoated samples. The results revealed the capability of the HA coating to significantly improve the corrosion resistance of the uncoated AZ91 alloy. - Highlights: • The nanostructured HA layer allows to control the degradation rate of the AZ91 alloy. • The HA coating significantly reduces the corrosion current density. • The HA coating significantly improves the polarization resistance in vitro. • The RF magnetron deposited HA coating promotes calcium-phosphate precipitation in SBF.

  19. Effect of thermal tempering on microstructure and mechanical properties of Mg-AZ31/Al-6061 diffusion bonding

    International Nuclear Information System (INIS)

    Jafarian, Mojtaba; Rizi, Mohsen Saboktakin; Jafarian, Morteza; Honarmand, Mehrdad; Javadinejad, Hamid Reza; Ghaheri, Ali; Bahramipour, Mohammad Taghi; Ebrahimian, Marzieh

    2016-01-01

    The objective of this study is to investigate the effect of the types thermal tempering of aluminum alloy on microstructure and mechanical properties of AZ31-O Mg and Al 6061-T6 diffusion bonding. Using Optical Microscope (OM) and Scanning Electron Microscopes (SEM) equipped with EDS analysis and line scan the interfaces of joints were evaluated. The XRD analysis was carried out to characterize phase constitution near the interface zone. The mechanical properties of joints were measured using Vickers micro-hardness and shear strength. According to the results in bonding of AZ31-Mg/Al-6061-O, in less plastic deformation in magnesium alloy, diffusion rate of most magnesium atoms occurred to aluminum alloy and formation of diffusion zone with minimum micro-hardness (140 HV) and maximum shear strength (32 MPa) compared to Al 6061-T6/Mg-AZ31 bonding. Evaluation of fracture surfaces indicates an occurrence of failure from the brittle intermetallic phases. - Highlights: • Diffusion bonding AZ31 to Al-6061withoutany interlayer was successful. • Thermal tempered aluminum alloy plays a vital role in the mechanical properties of joint. • Less thickness of reaction layers and micro-hardness in bonding annealed Al- 6061 layers to AZ31 was achieved. • Fracture surfaces indicated that the onset of fracture from intermetallic compounds resulted in fracture of the cleavage.

  20. Multivalent binding of PWWP2A to H2A.Z regulates mitosis and neural crest differentiation.

    Science.gov (United States)

    Pünzeler, Sebastian; Link, Stephanie; Wagner, Gabriele; Keilhauer, Eva C; Kronbeck, Nina; Spitzer, Ramona Mm; Leidescher, Susanne; Markaki, Yolanda; Mentele, Edith; Regnard, Catherine; Schneider, Katrin; Takahashi, Daisuke; Kusakabe, Masayuki; Vardabasso, Chiara; Zink, Lisa M; Straub, Tobias; Bernstein, Emily; Harata, Masahiko; Leonhardt, Heinrich; Mann, Matthias; Rupp, Ralph Aw; Hake, Sandra B

    2017-08-01

    Replacement of canonical histones with specialized histone variants promotes altering of chromatin structure and function. The essential histone variant H2A.Z affects various DNA-based processes via poorly understood mechanisms. Here, we determine the comprehensive interactome of H2A.Z and identify PWWP2A as a novel H2A.Z-nucleosome binder. PWWP2A is a functionally uncharacterized, vertebrate-specific protein that binds very tightly to chromatin through a concerted multivalent binding mode. Two internal protein regions mediate H2A.Z-specificity and nucleosome interaction, whereas the PWWP domain exhibits direct DNA binding. Genome-wide mapping reveals that PWWP2A binds selectively to H2A.Z-containing nucleosomes with strong preference for promoters of highly transcribed genes. In human cells, its depletion affects gene expression and impairs proliferation via a mitotic delay. While PWWP2A does not influence H2A.Z occupancy, the C-terminal tail of H2A.Z is one important mediator to recruit PWWP2A to chromatin. Knockdown of PWWP2A in Xenopus results in severe cranial facial defects, arising from neural crest cell differentiation and migration problems. Thus, PWWP2A is a novel H2A.Z-specific multivalent chromatin binder providing a surprising link between H2A.Z, chromosome segregation, and organ development. © 2017 The Authors.

  1. Correlative change of corrosion behavior with the microstructure of AZ91 Mg alloy modified with Y additions

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Ruiling, E-mail: jrl014014@163.com [College of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot, Inner Mongolia 010051 (China); Zhang, Ming; Zhang, Lina [College of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot, Inner Mongolia 010051 (China); Zhang, Wei [Laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of Sciences, 62 Wencui Road, Shenyang 110016 (China); Guo, Feng [College of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot, Inner Mongolia 010051 (China)

    2015-06-15

    Highlights: • The effect of Y addition into the AZ91 Mg alloys was investigated. • Initial stage of corrosion was studied by in-situ 3D digital microscopy observation. • The potential difference was investigated by Kelvin probe force microscopy. • The effect of Y addition on the corrosion mechanisms of AZ91 alloy was studied. - Abstract: Microstructure characterization of the AZ91 magnesium alloys with or without rare earth element yttrium (Y) has been revealed by SEM, EDS and EPMA. Some Y-rich phases can be found in the magnesium alloys with Y additions. The fraction of β-Mg{sub 17}Al{sub 12} phase obvious decreases and turns into granular distribution with the increase of Y addition instead of original wet distribution along grain boundaries. The results of the potentiodynamic polarization tests show that the corrosion resistance of AZ91 alloy is improved with appropriate Y additions. But an in-situ observation of 3D digital microscopy for the initial stage of corrosion of the magnesium alloy with 0.9%Y addition shows that Y-rich phases act as cathodic effect and the α phases in the vicinity of them acting as anode are corroded. So the additions of Y have a beneficial effect that can depress the overall corrosion of AZ91 alloy, whereas its harmful effect is related to Y-rich phases because they present the highest Volta potential difference from the adjacent matrix and they can drive galvanic corrosion.

  2. Correlative change of corrosion behavior with the microstructure of AZ91 Mg alloy modified with Y additions

    International Nuclear Information System (INIS)

    Jia, Ruiling; Zhang, Ming; Zhang, Lina; Zhang, Wei; Guo, Feng

    2015-01-01

    Highlights: • The effect of Y addition into the AZ91 Mg alloys was investigated. • Initial stage of corrosion was studied by in-situ 3D digital microscopy observation. • The potential difference was investigated by Kelvin probe force microscopy. • The effect of Y addition on the corrosion mechanisms of AZ91 alloy was studied. - Abstract: Microstructure characterization of the AZ91 magnesium alloys with or without rare earth element yttrium (Y) has been revealed by SEM, EDS and EPMA. Some Y-rich phases can be found in the magnesium alloys with Y additions. The fraction of β-Mg 17 Al 12 phase obvious decreases and turns into granular distribution with the increase of Y addition instead of original wet distribution along grain boundaries. The results of the potentiodynamic polarization tests show that the corrosion resistance of AZ91 alloy is improved with appropriate Y additions. But an in-situ observation of 3D digital microscopy for the initial stage of corrosion of the magnesium alloy with 0.9%Y addition shows that Y-rich phases act as cathodic effect and the α phases in the vicinity of them acting as anode are corroded. So the additions of Y have a beneficial effect that can depress the overall corrosion of AZ91 alloy, whereas its harmful effect is related to Y-rich phases because they present the highest Volta potential difference from the adjacent matrix and they can drive galvanic corrosion

  3. A biodegradable AZ91 magnesium alloy coated with a thin nanostructured hydroxyapatite for improving the corrosion resistance

    International Nuclear Information System (INIS)

    Mukhametkaliyev, T.M.; Surmeneva, M.A.; Vladescu, A.; Cotrut, C.M.; Braic, M.; Dinu, M.; Vranceanu, M.D.; Pana, I.; Mueller, M.; Surmenev, R.A.

    2017-01-01

    The main aim of this study was to investigate the properties of an AZ91 alloy coated with nanostructured hydroxyapatite (HA) prepared by radio frequency (RF) magnetron sputtering. The bioactivity and biomineralization of the AZ91 magnesium alloy coated with HA were investigated in simulated body fluid (SBF) via an in vitro test. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) analyses were performed. The samples were immersed in SBF to study the ability of the surface to promote the formation of an apatite layer as well as corrosion resistance and mass change of the HA-coated AZ91 alloy. Electrochemical tests were performed to estimate the corrosion behaviour of HA-coated and uncoated samples. The results revealed the capability of the HA coating to significantly improve the corrosion resistance of the uncoated AZ91 alloy. - Highlights: • The nanostructured HA layer allows to control the degradation rate of the AZ91 alloy. • The HA coating significantly reduces the corrosion current density. • The HA coating significantly improves the polarization resistance in vitro. • The RF magnetron deposited HA coating promotes calcium-phosphate precipitation in SBF.

  4. Effect of the Strain Rate on the Tensile Properties of the AZ31 Magnesium Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Seunghun; Park, Jiyoun; Choi, Ildong [Korea Maritime University, Busan (Korea, Republic of); Park, Sung Hyuk [Korea Institute of Materials Science, Changwon (Korea, Republic of)

    2013-10-15

    The effect of the strain rate at a range of 10‒4 ⁓ 3 × 10{sup 2}s{sup -}1 on the tensile characteristics of a rolled AZ31 magnesium alloy was studied. The normal tensile specimens were tested using a high rate hydraulic testing machine. Specimens were machined from four sheets with different thicknesses, 1, 1.5, 2 and 3 mm, along three directions, 0°, 45°, and 90° to the rolling direction. The results revealed that all the specimens had a positive strain rate sensitivity of strength, that is, the strength increased with increasing strain rate. This is the same tendency as other automotive steels have. Our results suggest that the AZ31 magnesium alloy has better collision characteristics at high strain rates because of improved strength with an increasing strain rate. Ductility decreased with an increasing strain rate with a strain rate under 1 s{sup -}1, but it increased with an increasing strain rate over 1 s{sup -}1. The mechanical properties of the AZ31 magnesium alloy depend on the different microstructures according to the thickness. Two and 3 mm thickness specimens with a coarse and non-uniform grain structure exhibited worse mechanical properties while the 1.5 mm thickness specimens with a fine and uniform grain structure had better mechanical properties. Specimens machined at 0° and 45° to the rolling direction had higher absorbed energy than that of the 90° specimen. Thus, we demonstrate it is necessary to choose materials with proper thickness and machining direction for use in automotive applications.

  5. Effect of the Strain Rate on the Tensile Properties of the AZ31 Magnesium Alloy

    International Nuclear Information System (INIS)

    Jeong, Seunghun; Park, Jiyoun; Choi, Ildong; Park, Sung Hyuk

    2013-01-01

    The effect of the strain rate at a range of 10‒4 ⁓ 3 × 10"2s"-1 on the tensile characteristics of a rolled AZ31 magnesium alloy was studied. The normal tensile specimens were tested using a high rate hydraulic testing machine. Specimens were machined from four sheets with different thicknesses, 1, 1.5, 2 and 3 mm, along three directions, 0°, 45°, and 90° to the rolling direction. The results revealed that all the specimens had a positive strain rate sensitivity of strength, that is, the strength increased with increasing strain rate. This is the same tendency as other automotive steels have. Our results suggest that the AZ31 magnesium alloy has better collision characteristics at high strain rates because of improved strength with an increasing strain rate. Ductility decreased with an increasing strain rate with a strain rate under 1 s"-1, but it increased with an increasing strain rate over 1 s"-1. The mechanical properties of the AZ31 magnesium alloy depend on the different microstructures according to the thickness. Two and 3 mm thickness specimens with a coarse and non-uniform grain structure exhibited worse mechanical properties while the 1.5 mm thickness specimens with a fine and uniform grain structure had better mechanical properties. Specimens machined at 0° and 45° to the rolling direction had higher absorbed energy than that of the 90° specimen. Thus, we demonstrate it is necessary to choose materials with proper thickness and machining direction for use in automotive applications.

  6. Influence of mictrostructure features on the corrosion behaviourof AZ91 alloy in chloride media

    Directory of Open Access Journals (Sweden)

    Lenka Bukovinová

    2014-11-01

    Full Text Available The influence of the microstructure of as-cast AZ91 magnesium alloy, which applied to solution annealing treatment and ageing treatment respectively, was evaluated in terms of its corrosion behaviour in 0.1 M NaCl solution at room temperature. The corrosion process was monitored by electrochemical impedance spectroscopy (EIS and the surface was characterized by scanning Kelvin probe force microscopy (SKPFM. The extent of corrosion damage was dependent on the microstructure. Surface potential maps indicated that, the surface potential of α-matrix is more positive than surface potential of β phase.

  7. Evaluation of 241-AZ tank farm supporting phase 1 privatization waste feed delivery

    Energy Technology Data Exchange (ETDEWEB)

    CARLSON, A.B.

    1998-11-19

    This evaluation is one in a series of evaluations determining the process needs and assessing the adequacy of existing and planned equipment in meeting those needs at various double-shell tank farms in support of Phase 1 privatization. A number of tank-to-tank transfers and waste preparation activities are needed to process and feed waste to the private contractor in support of Phase 1 privatization. The scope of this evaluation is limited to process needs associated with 241-AZ tank farm during the Phase 1 privatization.

  8. Evaluation of microstructural effects on the corrosion behaviour of AZ91D magnesium alloy

    DEFF Research Database (Denmark)

    Ambat, Rajan; Aung, Naing Naing; Zhou, W.

    2000-01-01

    The effect of microconstituents on the corrosion and electrochemical behaviour of AZ91D alloy prepared by die-casting and ingot casting route has been investigated in 3.5% NaCl solution at pH 7.25. The experimental techniques used include constant immersion technique, in-situ corrosion monitoring....... The corrosion products for ingot consisted of Mg(OH)(2) with small amounts beta phase, magnesium-aluminum oxide and MgH2 while for die-cast, the product showed a highly amorphous structure. (C) 2000 Elsevier Science Ltd. All rights reserved....

  9. Conversion Coatings Produced on AZ61 Magnesium Alloy by Low-Voltage Process

    Directory of Open Access Journals (Sweden)

    Nowak M.

    2016-03-01

    Full Text Available The resultes of anodic oxide conversion coatings on wrought AZ61 magnesium alloy production are describe. The studies were conducted in a solution containing: KOH (80 g/l and KF (300 g/l using anodic current densities of 3, 5 and 10 A/dm2 and different process durations. The obtained coatings were examined under a microscope and corrosion tests were performed by electrochemical method. Based on these results, it was found that the low-voltage process produces coatings conferring improved corrosion resistance to the tested magnesium alloy.

  10. Microstructure of Magnesium alloy AZ91-HP cast in permanent and non-permanent moulds

    DEFF Research Database (Denmark)

    Tiedje, Niels; Sørensen, Rasmus Kirkegaard; Albachari, Sami

    2003-01-01

    Casting of different geometries were made with AZ91-HP in different moulding media, so that a range of cooling conditions were obtained. Cooling curves were measured and compared to the microstructures found in the castings. It was shown that segregation in the alloy is highly dependent on cooling...... rate. This leads to precipitation of varying amounts of intermetallic phases. The distribution of phases in the material is controlled both by interdendritic and intergranular segregation, leading to an inhomogeneous microstructure. It is shown that local solidification time, segregation and diffusion...

  11. Structure and Mechanical Properties of Friction Stir Weld Joints of Magnesium Alloy AZ31

    Science.gov (United States)

    Nagasawa, T.; Otsuka, M.; Yokota, T.; Ueki, T.

    The applicability of friction stir welding to hot rolled sheet of commercial magnesium alloy AZ31 plates has been investigated. Friction stir weld joint showed mechanical strength comparable to that of base material, though the ductility remained at one half of that of the latter. The results are consistent with the microstructure which is characterized by a fine grained bond layer bounded by-intermediate grained base metals. It is found that both anodizing treatment and insertion of aluminum foil between batting faces do not degrade the joint properties at all. The results suggest that friction stir welding can be potentially applied to magnesium alloy.

  12. Microstructural Effects on the Spall Properties of ECAE-Processed AZ31B Magnesium Alloy

    Science.gov (United States)

    2016-10-01

    stresses using 51 mm and 105 mm bore gas guns . The Hugoniot Elastic Limit (HEL) was measured to be approximately 181 ± 3 MPa. The spall strengths...MD 21218, USA b Institute of Shock Physics, Imperial College London, London SW7 2AZ, UK c U.S. Army Research Laboratory, Aberdeen Proving Ground, MD...21005, USA d Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA A R T I C L E I N F O Article history: Received

  13. Constituyentes volátiles del mango de azúcar

    OpenAIRE

    Bautista., Edgar; Duque, Carmenza; Torres, Rafael

    2010-01-01

    Empleando Extracción de Volátiles por Espacio de Cabeza Dinámico y Extracción Líquido-Líquido, se estudió el aroma del mango de azúcar (Mangifera indica L), variedad nativa Colombiana apreciada por su exquisito aroma y sabor. Estos dos métodos complementarios permifieron la identificación, por Cromatografía de Gases de Alta resolución y Cromatografía de Gases de Alta Resolución - Espectrometría de Masas, de 52 coinponentes, entre los cuales sobresalieron como mayoritarios el 3-careno, el b...

  14. Microstructure and properties of friction stir butt-welded AZ31 magnesium alloy

    International Nuclear Information System (INIS)

    Wang Xunhong; Wang Kuaishe

    2006-01-01

    Friction stir welding (FSW) is a relatively new joining technique particularly for magnesium and aluminum alloys that are difficult to fusion weld. In this paper, an excellent friction stir weld of AZ31 magnesium alloy was obtained at proper parameter. In the friction stir zone (FSZ), the microstructure of the base material (BM) is replaced by fine grains and small particles of intermetallic compounds. The average microhardness of the friction stir zone is higher than that of the base material. The maximum tensile strength of joint can reach 93% that of the base material. And the failure locations are almost at the heating affected zone

  15. Evaluation of 241-AZ tank farm supporting phase 1 privatization waste feed delivery

    International Nuclear Information System (INIS)

    CARLSON, A.B.

    1998-01-01

    This evaluation is one in a series of evaluations determining the process needs and assessing the adequacy of existing and planned equipment in meeting those needs at various double-shell tank farms in support of Phase 1 privatization. A number of tank-to-tank transfers and waste preparation activities are needed to process and feed waste to the private contractor in support of Phase 1 privatization. The scope of this evaluation is limited to process needs associated with 241-AZ tank farm during the Phase 1 privatization

  16. Organic coatings silane-based for AZ91D magnesium alloy

    International Nuclear Information System (INIS)

    Hu Junying; Li Qing; Zhong Xiankang; Li Longqin; Zhang Liang

    2010-01-01

    Organic coatings silane-based containing electron withdrawing group or electron donating group have been synthesized and evaluated as prospective surface treatments for AZ91D magnesium alloy by hydrolysis and condensation reaction of the different silanes. Electrochemical tests were employed to confirm the corrosion resistance ability of the two kinds of organic coatings. The results showed that the coating with electron donating group had better corrosion protection performance. On the basis of the spatial configuration and the density of charge of those silanes molecules which was obtained through Gaussian 03 procedure based on B3LYP and density functional theory, combining experiment results, the rational explanation was provided.

  17. El azúcar y el ejercicio físico: su importancia en los deportistas

    OpenAIRE

    Ana B. Peinado; Miguel A. Rojo-Tirado; Pedro J. Benito

    2013-01-01

    El glucógeno muscular, principal almacén de glucosa en el organismo, y la glucemia sanguínea constituyen uno de los principales sustratos energéticos para la contracción muscular durante el ejercicio. El azúcar (sacarosa) es un estupendo suplemento al suministrar tanto glucosa como fructosa. Por ello, es esencial que los deportistas cuiden su alimentación, para mantener y aumentar los depósitos de este combustible, ya que las reservas de glucógeno muscular constituyen un factor limitante de l...

  18. Effect of magnesium hydride on the corrosion behavior of an AZ91 magnesium alloy in sodium chloride solution

    International Nuclear Information System (INIS)

    Chen Jian; Dong Junhua; Wang Jianqiu; Han Enhou; Ke Wei

    2008-01-01

    The effect of magnesium hydride on the corrosion behavior of an as-cast AZ91 alloy in 3.5 wt.% NaCl solution was investigated using gas collection method and potentiostatic test. The Pourbaix diagram of Mg-H 2 O system was built using thermodynamic calculation. It was possible that magnesium hydride could form in the whole pH range in theory. The experimental results showed that at cathodic region, magnesium hydride formed on surface, which was the controlling process for the corrosion behavior of AZ91 alloy; at anodic region and free corrosion potential, magnesium hydride model and partially protective film model, monovalent magnesium ion model and particle undermining model were responsible for the corrosion process of AZ91 alloy

  19. In vitro corrosion of pure magnesium and AZ91 alloy—the influence of thin electrolyte layer thickness

    Science.gov (United States)

    Zeng, Rong-Chang; Qi, Wei-Chen; Zhang, Fen; Li, Shuo-Qi

    2016-01-01

    In vivo degradation predication faces a huge challenge via in vitro corrosion test due to the difficulty for mimicking the complicated microenvironment with various influencing factors. A thin electrolyte layer (TEL) cell for in vitro corrosion of pure magnesium and AZ91 alloy was presented to stimulate the in vivo corrosion in the micro-environment built by the interface of the implant and its neighboring tissue. The results demonstrated that the in vivo corrosion of pure Mg and the AZ91 alloy was suppressed under TEL condition. The AZ91 alloy was more sensitive than pure Mg to the inhibition of corrosion under a TEL thickness of less than 200 µm. The TEL thickness limited the distribution of current, and thus localized corrosion was more preferred to occur under TEL condition than in bulk solution. The TEL cell might be an appropriate approach to simulating the in vivo degradation of magnesium and its alloys. PMID:26816655

  20. İstanbul Kıyı Balıkçılığında Kullanılan Dip Uzatma Ağlarının Teknik Özellikleri.

    Directory of Open Access Journals (Sweden)

    Taner Yıldız

    2015-12-01

    Full Text Available Bu çalışmayla, İstanbul kıyı balıkçılığında kullanılan dip uzatma ağlarının teknik özellikleri tespit edilmiştir. Bölgede altı adedi fanyalı ve yedi adedi sade olmak üzere toplam 13 tip dip uzatma ağı tanımlanmıştır. Bu uzatma ağlarının teknik planları FAO standartlarına göre ilk defa tanıtılmıştır

  1. A study of the deformation and failure mechanisms of protective intermetallic coatings on AZ91 Mg alloys using microcantilever bending

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Mingyuan; Mead, James; Wu, Yueqin; Russell, Hugh; Huang, Han, E-mail: han.huang@uq.edu.au

    2016-10-15

    In this study, a nanoindentation-based microcantilever bending technique was utilized to investigate the interfacial properties of a β-Mg{sub 17}Al{sub 12}/AZ91 Mg alloy film/substrate system under tensile loading conditions. Finite element analysis (FEA) was first undertaken to optimise the design of cantilever structures for inducing high tensile stresses at the interface. Cantilevers consisting of a necked region or notch at the interface were determined to be the most successful designs. Microcantilevers containing the β-Mg{sub 17}Al{sub 12}/AZ91 interface were then made using focused ion beam (FIB) milling technique. Necks were made in the cantilevers to intensify the tension at the interface and notches were used to introduce a stress concentration to the interface. During bending, the cantilevers were deflected to failure. Subsequent analysis of the deformed cantilevers using electron microscopies revealed that plastic deformation, and subsequent ductile rupture, of the AZ91 phase was the dominant failure mechanism. When the β-Mg{sub 17}Al{sub 12}/AZ91 film/substrate system was subjected to tension, the softer AZ91 phase failed prior to interfacial delamination, demonstrating that the strength of the interface exceeded the stresses that caused ductile failure in the substrate material. - Highlights: •Microcantilever bending was used to study the property of film/substrate interface. •FEA was used to optimise cantilever design for achieving high interfacial tension. •The intermetallic coatings on AZ91 substrate have strong interfacial adhesion.

  2. Conformal, planarizing and bridging AZ5214-E layers deposited by a 'draping' technique on non-planar III V substrates

    Science.gov (United States)

    Eliás, P.; Strichovanec, P.; Kostic, I.; Novák, J.

    2006-12-01

    A draping technique was tested for the deposition of positive-tone AZ5214-E photo-resist layers on non-planar (1 0 0)-oriented III-V substrates, which had a variety of three-dimensional (3D) topographies micromachined in them that consisted, e.g., of mesa ridges confined to side facets with variable tilt, inverted pyramidal holes and stubs confined to perpendicular side facets. All objects were sharp-edged. In each draping experiment, an AZ5214-E sheet was (1) formed floating on the water surface, (2) lowered onto a non-planar substrate and (3) draped over it during drying to form either self-sustained, or conformal, or planarizing layers over the non-planar substrates. The draping process is based on the depression of the glass transition temperature Tg of AZ5214-E material induced by penetrant water molecules that interact with AZ5214-E. During the process, the molecules are initially trapped under an AZ5214-E sheet and then transported out through the sheet via permeation. The water-AZ5214-E interaction modifies the stiffness κ of the sheet. The magnitude of the effect depends on temperature T and on partial water vapour pressure difference p(T, P, κ): the net effect is that Tg = f(C(T, P), p(T, P, κ)) is lowered as the concentration C of water increases with T and p, where P is the permeability of the sheet. The interaction depressed the Tg of the sheets as low as or lower than 53 °C for 6 µm thick sheets. At room temperature T Tg, the sheet becomes rubbery and mouldable by adhesion and capillary forces. As a result, it can either contour or planarize the topography depending on its geometry and thickness of the sheet.

  3. CSER 96-014: criticality safety of project W-151, 241-AZ-101 retrieval system process test

    Energy Technology Data Exchange (ETDEWEB)

    Vail, T.S., Fluor Daniel Hanford

    1997-02-06

    This Criticality Safety Evaluation Report (CSER) documents a review of the criticality safety implications of a process test to be performed in tank 241-AZ-101 (101-AZ). The process test will determine the effectiveness of the retrieval system for mobilization of solids and the practicality of the system for future use in the underground storage tanks at Hanford. The scope of the CSER extends only to the testing and operation of the mixer pumps and does not include the transfer of waste from the tank. Justification is provided that a nuclear criticality is extremely unlikely, if not impossible, in this tank.

  4. Comportamiento frente a la corrosión y biocompatibilidad in vitro/in vivo de la aleación AZ31 modificada superficialmente

    OpenAIRE

    Escudero, M. L.; Clemente, C.; Rubio, J. C.; Alobera, M. A.; García-Alonso, M. C.; del Valle, J. A.; Iglesias, C.; Pérez-Maceda, B. T.; Carboneras, M.; Lozano, R. M.

    2011-01-01

    The present work evaluates the corrosion behaviour and the in vitro/in vivo biocompatibility of the AZ31 magnesium alloy, which fulfills the mechanical requirements of bone. The corrosion kinetic of as-received AZ31 alloy was not compatible with the cell growth. To improve its performance, the AZ31 alloy was surface modified by a chemical conversion treatment in hydrofluoric acid. The magnesium fluoride layer generated by the surface treatment of AZ31 alloy enhances its corrosion behaviour, a...

  5. TiO2 Deposition on AZ31 Magnesium Alloy Using Plasma Electrolytic Oxidation

    Directory of Open Access Journals (Sweden)

    Leon White

    2013-01-01

    Full Text Available Plasma electrolytic oxidation (PEO has been used in the past as a useful surface treatment technique to improve the anticorrosion properties of Mg alloys by forming protective layer. Coatings were prepared on AZ31 magnesium alloy in phosphate electrolyte with the addition of TiO2 nanoparticles using plasma electrolytic oxidation (PEO. This present work focuses on developing a TiO2 functional coating to create a novel electrophotocatalyst while observing the surface morphology, structure, composition, and corrosion resistance of the PEO coating. Microstructural characterization of the coating was investigated by X-ray diffraction (XRD and scanning electron microscopy (SEM followed by image analysis and energy dispersive spectroscopy (EDX. The corrosion resistance of the PEO treated samples was evaluated with electrochemical impedance spectroscopy (EIS and DC polarization tests in 3.5 wt.% NaCl. The XRD pattern shows that the components of the oxide film include Mg from the substrate as well as MgO and Mg2TiO4 due to the TiO2 nanoparticle addition. The results show that the PEO coating with TiO2 nanoparticles did improve the corrosion resistance when compared to the AZ31 substrate alloy.

  6. Room Temperature Shear Band Development in Highly Twinned Wrought Magnesium AZ31B Sheet

    Science.gov (United States)

    Scott, Jon; Miles, Michael; Fullwood, David; Adams, Brent; Khosravani, Ali; Mishra, Raja K.

    2013-01-01

    Failure mechanisms were studied in wrought AZ31B magnesium alloy after forming under different strain paths. Optical micrographs were used to observe the shear band formation and regions of high twin density in samples strained under uniaxial, biaxial, and plane strain conditions. Interrupted testing at 4 pct effective strain increments, until failure, was used to observe the evolution of the microstructure. The results showed that shear bands, with a high percentage of twinned grains, appeared early in the samples strained under biaxial or plane strain tension. These bands are similar to those seen in uniaxial tension specimens just prior to failure where the uniaxial tensile ductility was much greater than that observed for plane strain or biaxial tension conditions. A forming limit diagram for AZ31B, which was developed from the strain data, showed that plane strain and biaxial tension had very similar limit strains; this contrasts with materials like steel or aluminum alloys, which typically have greater ductility in biaxial tension compared to plane strain tension.

  7. Near-liquidus forging, partial remelting and thixoforging of an AZ91D + Y magnesium alloy

    International Nuclear Information System (INIS)

    Zhao Zude; Chen Qiang; Hu Chuankai; Huang Shuhai; Wang Yuanqing

    2009-01-01

    A new route, near-liquidus forging plus partial remelting, has been developed for obtaining globular microstructures. Firstly, a material is formed by near-liquidus forging for obtaining a fine dendritic microstructure. Globular microstructure can be produced by reheating the material into the semi-solid temperature range for a period of time. In this paper, an AZ91D alloy with the addition of yttrium was prepared by near-liquidus forging. Microstructure evolution during partial remelting was studied at temperatures and for times. Tensile mechanical properties of thixoforged components were also determined. It is shown that the fine dendritic structure firstly evolves into a blocky structure during partial remelting. With prolonged holding time, the blocky structure disintegrates into polygonal solid particles. Prolonging time and increasing temperature promote a faster spheroidization. Good mechanical properties are obtained for the thixoforged AZ91D alloy with the addition of yttrium prepared by near-liquidus forging, with a yield strength of 160.9 MPa and a ultimate tensile strength of 301.7 MPa and a elongation to fracture of 9.734%.

  8. Microstructural characterization and finite element modeling of AZ31 magnesium alloys welded joints

    Directory of Open Access Journals (Sweden)

    José A. Segarra

    2018-03-01

    Full Text Available In this article, it has been studied how the microstructure of AZ31 magnesium alloy can be affected by the thermic cycles produced by welding processes, trying to modeling by element finite software the thermic cycles in this material. The AZ31 samples tested were welded using Gas Tugsten Arc Welding (GTAW and different filler materials. For this investigation, optic microscopy, scanning electronic microscopy, and finite elements method software has been used. This work indicates in one hand that in this type of alloys the microconstituyentes are Al-Mn o Al-Mn-Mg compounds, the presence of β-phase cannot be found at room temperature in this research at room, on the other hand the obtained simulation models indicate that the recrystallization takes place in the areas which reach maximum temperatures around 550 °C, this value is also the limit of the dissolution area for the Al-Mn o Al-Mn-Mg precipitated particles which are very likely to act as inhibitors of the corrosion in NaCl electrolytes.

  9. Mechanical properties of AZ31 alloy processed by a green metallurgy route

    International Nuclear Information System (INIS)

    D'Enrico, F.; Garces, G.; Hofer, M.; Kim, S. K.; Perez, P.; Cabeza, S.; Adeva, P.

    2013-01-01

    Recently it has been proved that molding of defect-free components of various commercial alloys of magnesium can be carried out successfully when small amounts of CaO are added to the melt, making unnecessary the use of SF 6 coverage. In the case of AZ alloys, this process also remarkably improves their mechanical properties not only by the greater cleaning of alloys but also by the formation of CaAl 2 phase. This work, part of the Green project Metallurgy (http://www.green-metallurgy.eu) funded by the European Union (LIFE+2009), studies the influence of different CaO additions on the microstructure and mechanical properties of AZ31 Eco-Mg alloy. The alloy was processed by a conventional route involving extrusion of as-cast rods as well as by a powder metallurgy route (PM) using chips as starting material. The objective was to analyze the viability of recycling machining chips to manufacture components for the automobile industry and transportation in general, because of its low cost and environmental impact. It has been demonstrated that alloys processed from chips exhibit the highest tensile stress values, close to 320 MPa. (Author)

  10. Sealing of PEO Coated AZ91 Magnesium Alloy Using La-Based Solutions

    Directory of Open Access Journals (Sweden)

    Luca Pezzato

    2017-01-01

    Full Text Available In this work, solutions containing lanthanum salts were used for a post-treatment of sealing to increase the corrosion resistance of PEO coated AZ91 alloy. PEO coatings were produced on samples of AZ91 magnesium alloy using an alkaline solution containing sodium hydroxide, sodium phosphates, and sodium silicates. The sealing treatment was performed in a solution containing 12 g/L of La(NO33 at pH 4 at different temperatures and for different treatment times. Potentiodynamic polarization test, an EIS test, showed that the sealing treatment with solution containing lanthanum nitrate caused a remarkable increase in the corrosion resistance. The corrosion behavior was correlated with the surface morphology and elemental composition evaluated with scanning electron microscope (SEM, X-ray diffraction (XRD, and X-ray photoelectron spectroscopy (XPS. In particular, the sealing treatment at 50°C for 30 min resulted in being the most promising to increase the corrosion properties of PEO treated samples because of the formation of a homogeneous sealing layer, mainly composed of La(OH3.

  11. Novel hybrid sol-gel coatings for corrosion protection of AZ31B magnesium alloy

    International Nuclear Information System (INIS)

    Lamaka, S.V.; Montemor, M.F.; Galio, A.F.; Zheludkevich, M.L.; Trindade, C.; Dick, L.F.; Ferreira, M.G.S.

    2008-01-01

    This work aims to develop and study new anticorrosion films for AZ31B magnesium alloy based on the sol-gel coating approach. Hybrid organic-inorganic sols were synthesized by copolymerization of epoxy-siloxane and titanium or zirconium alkoxides. Tris(trimethylsilyl) phosphate was also used as additive to confer additional corrosion protection to magnesium-based alloy. A sol-gel coating, about 5-μm thick, shows good adhesion to the metal substrate and prevents corrosion attack in 0.005 M NaCl solution for 2 weeks. The sol-gel coating system doped with tris(trimethylsilyl)-phosphate revealed improved corrosion protection of the magnesium alloy due to formation of hydrolytically stable Mg-O-P chemical bonds. The structure and the thickness of the sol-gel film were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The corrosion behaviour of AZ31B substrates pre-treated with the sol-gel derived hybrid coatings was tested by electrochemical impedance spectroscopy (EIS). The chemical composition of the silylphosphate-containing sol-gel film at different depths was investigated by X-ray photoelectron spectroscopy (XPS) with depth profiling

  12. Environmental friendly anodizing of AZ91D magnesium alloy in alkaline borate-benzoate electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Liu Yan [Department of Chemistry, Zhejiang University, Hangzhou 310027 (China); Department of Chemistry, Tianshui Normal University, Tianshui 741000 (China); Wei Zhongling [Magnesium Technology Co., Ltd., Chinese Academy of Sciences, Jiaxing 314051 (China); Yang Fuwei [Department of Chemistry, Tianshui Normal University, Tianshui 741000 (China); Zhang Zhao, E-mail: eaglezzy@zjuem.zju.edu.cn [Department of Chemistry, Zhejiang University, Hangzhou 310027 (China); Key Laboratory for Light Alloy Materials Technology, Jiaxing 314051 (China)

    2011-06-02

    Highlights: > Environmental friendly PEO technology for AZ91 magnesium alloy is developed. > NaBz is used as new additive and it is low-cost and environmental friendly. > The effect of NaBz additive on the properties of the anodized film was studied. > Anodized film with excellent corrosion resistance is obtained. > The forming mechanism of anodized film in the presence of NaBz is approached. - Abstract: A kind of environmental friendly anodizing routine for AZ91D magnesium alloy, based on an alkaline borate-sodium benzoate electrolyte (NaBz) was studied. The effect of NaBz on the properties of the anodized film was investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrometry (EDS), potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), respectively. The results showed that the anodizing process, surface morphology, thickness, phase structure and corrosion resistance of the anodized film were strongly dependent on the concentration of NaBz. In the presence of adequate NaBz, a thick, compact and smoothing anodized film with excellent corrosion resistance was produced. Moreover, the forming mechanism of the anodized film in the presence of NaBz additive was also approached, which was a suppression of arc discharge process by the adsorption of Bz{sup -} on the surface of magnesium alloy substrate.

  13. Thermal Microstructural Stability of AZ31 Magnesium after Severe Plastic Deformation

    Energy Technology Data Exchange (ETDEWEB)

    Young, John P.; Askari, Hesam A.; Hovanski, Yuri; Heiden, Michael J.; Field, David P.

    2015-03-01

    Both equal channel angular pressing and friction stir processing have the ability to refine the grain size of twin roll cast AZ31 magnesium and potentially improve its superplastic properties. This work used isochronal and isothermal heat treatments to investigate the microstructural stability of twin roll cast, equal channel angular pressed and friction stir processed AZ31 magnesium. For both heat treatment conditions, it was found that the twin roll casted and equal channel angular pressed materials were more stable than the friction stir processed material. Calculations of the grain growth kinetics showed that severe plastic deformation processing decreased the activation energy for grain boundary motion with the equal channel angular pressed material having the greatest Q value of the severely plastically deformed materials and that increasing the tool travel speed of the friction stir processed material improved microstructural stability. The Hollomon-Jaffe parameter was found to be an accurate means of identifying the annealing conditions that will result in substantial grain growth and loss of potential superplastic properties in the severely plastically deformed materials. In addition, Humphreys’s model of cellular microstructural stability accurately predicted the relative microstructural stability of the severely plastically deformed materials and with some modification, closely predicted the maximum grain size ratio achieved by the severely plastically deformed materials.

  14. Improvement of high temperature fatigue lifetime in AZ91 magnesium alloy by heat treatment

    Energy Technology Data Exchange (ETDEWEB)

    Mokhtarishirazabad, Mehdi [School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Azadi, Mohammad, E-mail: m_azadi@ip-co.com [Fatigue and Wear Workgroup, Irankhodro Powertrain Company (IPCO), Tehran (Iran, Islamic Republic of); Hossein Farrahi, Gholam [School of Mechanical Engineering, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Winter, Gerhard; Eichlseder, Wilfred [Chair of Mechanical Engineering, University of Leoben, Leoben (Austria)

    2013-12-20

    In the present paper, an improvement in high temperature fatigue properties of the AZ91 magnesium alloy with rare earth elements has been obtained by a typical heat treatment, denoted by T6. For this objective, out-of-phase thermo-mechanical fatigue, room temperature and high temperature low cycle fatigue tests are performed to compare lifetimes. Several rare earth elements are initially added to the AZ91 alloy during a gravity casting process in permanent molds. Also, the type of the heat treatment is examined. Results of specimens with only the solution (the T4 heat treatment) and the solution with the ageing process (the T6 heat treatment) are compared under isothermal fatigue loadings. Microstructural investigations are carried out, before and after fatigue experiments to demonstrate the heat treatment effect. Results showed that both low cycle fatigue and thermo-mechanical fatigue of the alloy at high temperatures increases tremendously after the T6 heat treatment. This behavior attributes to the variation of the ductility, which was a result of microstructural changes during the heat treatment and the varying temperature in fatigue tests.

  15. El medievalismo fértil de Paloma Díaz-Mas

    Directory of Open Access Journals (Sweden)

    Rafael M. Mérida Jiménez

    2001-01-01

    Full Text Available The author of this article is concerned with trying to understand why Paloma Díaz-Mas, the writer of such an excellent novel as La tierra fértil (1999, has not received much critical attention. He underlines three main reasons. First, she does not live in Madrid or Barcelona and so she is far away from the main centres of cultural power. Second, she teaches Spanish literature in the Basque Country, a political and linguistic community which significantly differs from that of many other writers. Third, she writes historical novels, which does not appear to be very fashionable in Spain these days. Moreover, Díaz-Mas is a woman writer who does not make use of the most commonly available feminine patterns, and she does not seem to offer a model easy to include in a given feminist methodology either. However, Mérida-Jiménez argues that Paloma provides an intelligent deconstruction of “male authority” through subtle rhetorical means, as well as a representation of the weakness of his “domination” in very innovative ways, such as those derived from the dialectics between history and fiction, centrality and marginality, heterosexuality and homosexuality, individual and society, dream and reason or tradition and modernity.

  16. Microstructure control during twin roll casting of an AZ31 magnesium alloy

    International Nuclear Information System (INIS)

    Huang, Y; Bayandorian, I; Fan, Z

    2012-01-01

    The existing twin roll casting technique for magnesium alloys suffers heterogeneity in both microstructure and chemistry and downstream processing is required to improve the strip quality, resulting in cost rise. In the present work, twin roll casting was carried out using an AZ31 magnesium alloy, with the application of intensive shearing melt conditioning prior to casting. The effect of process parameters such as pouring temperature and casting speed on microstructure control during casting and subsequent downstream processing was studied. Experimental results showed that the melt conditioning treatment allowed the production of AZ31 strips with uniform and refined microstructure free of centreline segregations. It was also shown that an optimized combination of pouring temperature and casting speed, in conjunction with a strip thickness control operation, resulted in uniformly distributed stored energies due to enhanced plastic deformation, which promoted recrystallization during casting and subsequent heat treatment. Strips prepared by twin roll casting and homogenization developed similar microstructural features to those prepared by twin roll casting followed by lengthy downstream processing by homogenization, hot rolling and annealing and displayed a weaker basal texture, exhibiting a potentially better formability.

  17. Investigation of the AZ 5214E photoresist by the laser interference, EBDW and NSOM lithographies

    Energy Technology Data Exchange (ETDEWEB)

    Škriniarová, J., E-mail: jaroslava.skriniarova@stuba.sk [Institute of Electronics and Photonics, Slovak University of Technology, Bratislava (Slovakia); Pudiš, D. [Department of Physics, University of Žilina, Žilina (Slovakia); Andok, R. [Department of E-Beam Lithography, Institute of Informatics, Slovak Academy of Sciences, Bratislava (Slovakia); Lettrichová, I. [Department of Physics, University of Žilina, Žilina (Slovakia); Uherek, F. [Institute of Electronics and Photonics, Slovak University of Technology, Bratislava (Slovakia)

    2017-02-15

    Highlights: • Applicability of the AZ 5214E photoresist for three different lithographies. • Useful for the fabrication of 1D and 2D periodic and irregular structures. • 2D structures with 260 nm period achieved by the laser interference lithography. • Structures with period below 500 nm achieved with the e-beam direct-write lithography. • Holes of 270 nm diameter made by the near-field scanning optical microscopy lithography. - Abstract: In this paper we show a comparison of chosen lithographies used for the AZ 5214E photoresist, which is normally UV sensitive but has also been investigated for its sensitivity to e-beam exposure. Three lithographies, the E-Beam Direct Write lithography (EBDW), laser Interference Lithography (IL) and the non-contact Near-field Scanning Optical Microscopy (NSOM) lithography, are discussed here and the results on exposed arrays of simple patterns are shown. With the EBDW and IL we achieved periods of the structures around half-micron, and we demonstrate attainability of dimensions smaller or comparable than usually achieved by a standard optical photolithography with the investigated photoresist. With the non-contact NSOM lithography structures with periods slightly above a micron were achieved.

  18. Corrosion behaviors in physiological solution of cerium conversion coatings on AZ31 magnesium alloy

    International Nuclear Information System (INIS)

    Cui Xiufang; Yang Yuyun; Liu Erbao; Jin Guo; Zhong Jinggao; Li Qingfen

    2011-01-01

    In this paper, a non-toxic Ce-based conversion coating was obtained on the surface of bio-medical AZ31 magnesium alloys. The micro-morphology of the coating prepared with optimal technical parameters and immersed in physiological solution (Hank's solution) in different time was observed by scanning electron microscopy (SEM), composition of the cerium conversion coating and corrosion products in Hank's solution were characterized by X-ray photoelectron spectroscopy (XPS) and energy dispersive spectroscopy (EDS), respectively. In addition, the corrosion property in Hank's solution was studied by electrochemical experiment and immersion test. The results show that the dense Ce-based conversion coating is obtained on the surface of AZ31 magnesium alloys in optimal technical parameters and the conversion coating consists of a mass of trivalent and tetravalent cerium oxides. The cerium conversion coating can provide obvious protection of magnesium alloys and can effectively reduce the degradation speed in Hank's solution. Also the degradation products have little influence on human body.

  19. Tailoring degradation of AZ31 alloy by surface pre-treatment and electrospun PCL fibrous coating

    Energy Technology Data Exchange (ETDEWEB)

    Hanas, T. [Medical Materials Laboratory, Indian Institute of Technology Madras, Chennai 600036 (India); School of Nano Science and Technology, National Institute of Technology Calicut, Calicut, Kerala 673601 (India); Sampath Kumar, T.S., E-mail: tssk@iitm.ac.in [Medical Materials Laboratory, Indian Institute of Technology Madras, Chennai 600036 (India); Perumal, Govindaraj; Doble, Mukesh [Department of Biotechnology - Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036 (India)

    2016-08-01

    AZ31 magnesium alloy was coated with polycaprolactone (PCL) nano-fibrous layer using electrospinning technique so as to control degradation in physiological environment. Before coating, the alloy was treated with HNO{sub 3} to have good adhesion between the coating and substrate. To elucidate the role of pre-treatment and coating, samples only with PCL coating as well as HNO{sub 3} treatment only were prepared for comparison. Best coating adhesion of 4B grade by ASTM D3359–09 tape test was observed for pre-treated samples. The effect of coating on in vitro degradation and biomineralization was studied using supersaturated simulated body fluid (SBF 5 ×). The weight loss and corrosion results obtained by immersion test showed that the combination of HNO{sub 3} pre-treatment and PCL coating is very effective in controlling the degradation rate and improving bioactivity. Cytotoxicity studies using L6 cells showed that PCL coated sample has better cell adhesion and proliferation compared to uncoated samples. Nano-fibrous PCL coating combined with prior acid treatment seems to be a promising method to tailor degradation rate with enhanced bioactivity of Mg alloys. - Highlights: • PCL electrospun coating on HNO{sub 3} pre-treated AZ31 alloy controls biodegradation. • Acid pre-treatment stabilizes the substrate - coating interface. • Electrospun porous coating improves biomineralization. • Coating similar to extracellular matrix enhances cell adhesion.

  20. Environmental friendly anodizing of AZ91D magnesium alloy in alkaline borate-benzoate electrolyte

    International Nuclear Information System (INIS)

    Liu Yan; Wei Zhongling; Yang Fuwei; Zhang Zhao

    2011-01-01

    Highlights: → Environmental friendly PEO technology for AZ91 magnesium alloy is developed. → NaBz is used as new additive and it is low-cost and environmental friendly. → The effect of NaBz additive on the properties of the anodized film was studied. → Anodized film with excellent corrosion resistance is obtained. → The forming mechanism of anodized film in the presence of NaBz is approached. - Abstract: A kind of environmental friendly anodizing routine for AZ91D magnesium alloy, based on an alkaline borate-sodium benzoate electrolyte (NaBz) was studied. The effect of NaBz on the properties of the anodized film was investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrometry (EDS), potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), respectively. The results showed that the anodizing process, surface morphology, thickness, phase structure and corrosion resistance of the anodized film were strongly dependent on the concentration of NaBz. In the presence of adequate NaBz, a thick, compact and smoothing anodized film with excellent corrosion resistance was produced. Moreover, the forming mechanism of the anodized film in the presence of NaBz additive was also approached, which was a suppression of arc discharge process by the adsorption of Bz - on the surface of magnesium alloy substrate.

  1. Effects of filter materials on microstructure and mechanical properties of AZ91

    Directory of Open Access Journals (Sweden)

    Wu Guohua

    2010-11-01

    Full Text Available The present investigation studied the effects of different kinds of ceramic foam filters (CFF incorporating gas bubbling on the microstructure and mechanical properties of virgin AZ91 alloys, and the reactions between filters and Mg melt during filtration. The results show that the purification process of CFF incorporating gas bubbling process can obviously improve the Rm and A of AZ91 alloy, especially the A. Amongst the selected four kinds of CFF, the MgO filter is the most suitable for filtrating Mg melt, and the filtration effective sequence of four kinds of filtrating materials is as follows: MgO>Al2O3>ZrO2>SiC. With MgO filter incorporating gas bubbling treatment under Ar flow rate of 2 L/min and temperature of 730 °C, the ultimate tensile strength Rm and elongation A can be improved greatly from 175.3 MPa and 2.74% to 195.4 MPa and 4.54%, respectively. No inclusions are found on the fracture surface of the sample filtrated by MgO ceramic foam filter, and the fracture mode is quasi-cleavage crack.

  2. The surface chemistry of 3-mercaptopropyltrimethoxysilane films deposited on magnesium alloy AZ91

    International Nuclear Information System (INIS)

    Scott, A.; Gray-Munro, J.E.

    2009-01-01

    Magnesium and its alloys have desirable physical and mechanical properties for a number of applications. Unfortunately, these materials are highly susceptible to corrosion, particularly in the presence of aqueous solutions. The purpose of this study is to develop a uniform, non-toxic surface treatment to enhance the corrosion resistance of magnesium alloys. This paper reports the influence of the coating bath parameters and alloy microstructure on the deposition of 3-mercaptopropyltrimethoxysilane (MPTS) coatings on magnesium alloy AZ91. The surface chemistry at the magnesium/MPTS interface has also been explored. The results indicate that the deposition of MPTS onto AZ91 was influenced by both the pH and MPTS concentration in the coating bath. Furthermore, scanning electron microscopy results showed that the MPTS film deposited uniformly on all phases of the magnesium alloy surface. X-ray photoelectron spectroscopy studies revealed that at the magnesium/MPTS interface, the molecules bond to the surface through the thiol group in an acid-base interaction with the Mg(OH) 2 layer, whereas in the bulk of the film, the molecules are randomly oriented.

  3. Electrophoretic deposition of nanostructured hydroxyapatite coating on AZ91 magnesium alloy implants with different surface treatments

    Energy Technology Data Exchange (ETDEWEB)

    Rojaee, Ramin, E-mail: raminrojaee@aim.com [Biomaterials Research Group, Department of Materials Engineering, Isfahan University of Technology, Isfahan, 84156-83111 (Iran, Islamic Republic of); Fathi, Mohammadhossein [Biomaterials Research Group, Department of Materials Engineering, Isfahan University of Technology, Isfahan, 84156-83111 (Iran, Islamic Republic of); Dental Materials Research Center, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of); Raeissi, Keyvan [Department of Materials Engineering, Isfahan University of Technology, Isfahan, 84156-83111 (Iran, Islamic Republic of)

    2013-11-15

    Bio-absorbable magnesium (Mg) based alloys have been introduced as innovative orthopedic implants during recent years. It has been specified that rapid degradation of Mg based alloys in physiological environment should be restrained in order to be utilized in orthopedic trauma fixation and vascular intervention. In this developing field of healthcare materials, micro-arc oxidation (MAO), and MgF{sub 2} conversion coating were exploited as surface pre-treatment of AZ91 magnesium alloy to generate a nanostructured hydroxyapatite (n-HAp) coating via electrophoretic deposition (EPD) method. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and transmission electron microscopy (TEM) techniques were used to characterize the obtained powder and coatings. The potentiodynamic polarization tests were carried out to evaluate the corrosion behavior of the coated and uncoated specimens, and in vitro bioactivity evaluation were performed in simulated body fluid. Results revealed that the MAO/n-HAp coated AZ91 Mg alloy samples with a rough topography and lower corrosion current density leads to a lower Mg degradation rate accompanied by high bioactivity.

  4. Research on the drawing process with a large total deformation wires of AZ31 alloy

    International Nuclear Information System (INIS)

    Bajor, T; Muskalski, Z; Suliga, M

    2010-01-01

    Magnesium and their alloys have been extensively studied in recent years, not only because of their potential applications as light-weight engineering materials, but also owing to their biodegradability. Due to their hexagonal close-packed crystallographic structure, cold plastic processing of magnesium alloys is difficult. The preliminary researches carried out by the authors have indicated that the application of the KOBO method, based on the effect of cyclic strain path change, for the deformation of magnesium alloys, provides the possibility of obtaining a fine-grained structure material to be used for further cold plastic processing with large total deformation. The main purpose of this work is to present research findings concerning a detailed analysis of mechanical properties and changes occurring in the structure of AZ31 alloy wire during the multistage cold drawing process. The appropriate selection of drawing parameters and the application of multistep heat treatment operations enable the deformation of the AZ31 alloy in the cold drawing process with a total draft of about 90%.

  5. Characterization of fold defects in AZ91D and AE42 magnesium alloy permanent mold castings

    International Nuclear Information System (INIS)

    Bichler, L.; Ravindran, C.

    2010-01-01

    Casting premium-quality magnesium alloy components for aerospace and automotive applications poses unique challenges. Magnesium alloys are known to freeze rapidly prior to filling a casting cavity, resulting in misruns and cold shuts. In addition, melt oxidation, solute segregation and turbulent metal flow during casting contribute to the formation of fold defects. In this research, formation of fold defects in AZ91D and AE42 magnesium alloys cast via the permanent mold casting process was investigated. Computer simulations of the casting process predicted the development of a turbulent metal flow in a critical casting region with abrupt geometrical transitions. SEM and light optical microscopy examinations revealed the presence of folds in this region for both alloys. However, each alloy exhibited a unique mechanism responsible for fold formation. In the AZ91D alloy, melt oxidation and velocity gradients in the critical casting region prevented fusion of merging metal front streams. In the AE42 alloy, limited solubility of rare-earth intermetallic compounds in the α-Mg phase resulted in segregation of Al 2 RE particles at the leading edge of a metal front and created microstructural inhomogeneity across the fold.

  6. Geologie study off gravels of the Agua Fria River, Phoenix, AZ

    Science.gov (United States)

    Langer, W.H.; Dewitt, E.; Adams, D.T.; O'Briens, T.

    2010-01-01

    The annual consumption of sand and gravel aggregate in 2006 in the Phoenix, AZ metropolitan area was about 76 Mt (84 million st) (USGS, 2009), or about 18 t (20 st) per capita. Quaternary alluvial deposits in the modern stream channel of the Agua Fria River west of Phoenix are mined and processed to provide some of this aggregate to the greater Phoenix area. The Agua Fria drainage basin (Fig. 1) is characterized by rugged mountains with high elevations and steep stream gradients in the north, and by broad alluvial filled basins separated by elongated faultblock mountain ranges in the south. The Agua Fria River, the basin’s main drainage, flows south from Prescott, AZ and west of Phoenix to the Gila River. The Waddel Dam impounds Lake Pleasant and greatly limits the flow of the Agua Fria River south of the lake. The southern portion of the watershed, south of Lake Pleasant, opens out into a broad valley where the river flows through urban and agricultural lands to its confluence with the Gila River, a tributary of the Colorado River.

  7. Ultrasonic Examination of Double-Shell Tank 241-AZ-102 Examination Completed August 2003

    International Nuclear Information System (INIS)

    Pardini, Allan F.; Posakony, Gerald J.

    2003-01-01

    COGEMA Engineering Corporation (COGEMA), under a contract from CH2M Hill Hanford Group (CH2M Hill), has performed an ultrasonic nondestructive examination of selected portions of Double-Shell Tank 241-AZ-102. The purpose of this examination was to provide information that could be used to evaluate the integrity of the wall of the primary tank. The requirements for the ultrasonic examination of Tank 241-AZ-102 were to detect, characterize (identify, size, and locate), and record measurements made of any wall thinning, pitting, or cracks that might be present in the wall of the primary tank. Any measurements that exceed the requirements set forth in the Engineering Task Plat (ETP), RPP-11832 (Jensen 2002) and summarized on page 1 of this document, are reported to CH2M Hill and the Pacific Northwest National Laboratory (PNNL) for further evaluation. Under the contract with CH2M Hill, all data is to be recorded on disk and paper copies of all measurements are provided to PNNL for third-party evaluation. PNNL is responsible for preparing a report that describes the results of the COGEMA ultrasonic examinations

  8. Improvement of high temperature fatigue lifetime in AZ91 magnesium alloy by heat treatment

    International Nuclear Information System (INIS)

    Mokhtarishirazabad, Mehdi; Azadi, Mohammad; Hossein Farrahi, Gholam; Winter, Gerhard; Eichlseder, Wilfred

    2013-01-01

    In the present paper, an improvement in high temperature fatigue properties of the AZ91 magnesium alloy with rare earth elements has been obtained by a typical heat treatment, denoted by T6. For this objective, out-of-phase thermo-mechanical fatigue, room temperature and high temperature low cycle fatigue tests are performed to compare lifetimes. Several rare earth elements are initially added to the AZ91 alloy during a gravity casting process in permanent molds. Also, the type of the heat treatment is examined. Results of specimens with only the solution (the T4 heat treatment) and the solution with the ageing process (the T6 heat treatment) are compared under isothermal fatigue loadings. Microstructural investigations are carried out, before and after fatigue experiments to demonstrate the heat treatment effect. Results showed that both low cycle fatigue and thermo-mechanical fatigue of the alloy at high temperatures increases tremendously after the T6 heat treatment. This behavior attributes to the variation of the ductility, which was a result of microstructural changes during the heat treatment and the varying temperature in fatigue tests

  9. Cyclic deformation and fatigue of rolled AZ80 magnesium alloy along different material orientations

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Ying, E-mail: yxiong@zjut.edu.cn [Key Laboratory of Special Purpose Equipment and Advanced Processing Technology, Ministry of Education, Zhejiang University of Technology, Hangzhou, Zhejiang 310032 (China); College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang 310032 (China); Jiang, Yanyao, E-mail: yjiang@unr.edu [University of Nevada, Reno, Department of Mechanical Engineering, Reno, NV 89557 (United States)

    2016-11-20

    The effect of material orientation on cyclic deformation and fatigue behavior of rolled AZ80 magnesium (Mg) alloy was experimentally investigated under fully reversed strain-controlled loading in ambient. The testing specimens were taken from a rolled AZ80 Mg plate at four orientations with respect to rolled plane: 0°(ND, normal direction), 30°(ND30), 60°(ND60), and 90°(RD, rolled direction). Fatigue fracture morphologies of specimens along different orientation were analyzed by scanning electron microscopy (SEM). Overall cyclic hardening was observed for the material loaded in different directions. For a given strain amplitude, the ND specimens had the lowest fatigue resistance among the specimens of all material orientations. The fatigue life of an ND30 specimens is similar to that of an ND60 specimen at a given strain amplitude and both are higher than that of an RD specimen when the strain amplitude is higher than 0.4%, whereas an RD specimen exhibits a better fatigue resistance when the strain amplitude is lower than 0.4%. A mixed fracture mode with transgranular and intergranular cracking related to lamellar-like features occurred during stable crack growth, and an intergranular fracture mode related to dimple-like features exhibited in the fast fracture region. A multiaxial fatigue model based on the strain energy density can correlate all the fatigue experiments of the material at different material orientations.

  10. Electrophoretic deposition of nanostructured hydroxyapatite coating on AZ91 magnesium alloy implants with different surface treatments

    International Nuclear Information System (INIS)

    Rojaee, Ramin; Fathi, Mohammadhossein; Raeissi, Keyvan

    2013-01-01

    Bio-absorbable magnesium (Mg) based alloys have been introduced as innovative orthopedic implants during recent years. It has been specified that rapid degradation of Mg based alloys in physiological environment should be restrained in order to be utilized in orthopedic trauma fixation and vascular intervention. In this developing field of healthcare materials, micro-arc oxidation (MAO), and MgF 2 conversion coating were exploited as surface pre-treatment of AZ91 magnesium alloy to generate a nanostructured hydroxyapatite (n-HAp) coating via electrophoretic deposition (EPD) method. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and transmission electron microscopy (TEM) techniques were used to characterize the obtained powder and coatings. The potentiodynamic polarization tests were carried out to evaluate the corrosion behavior of the coated and uncoated specimens, and in vitro bioactivity evaluation were performed in simulated body fluid. Results revealed that the MAO/n-HAp coated AZ91 Mg alloy samples with a rough topography and lower corrosion current density leads to a lower Mg degradation rate accompanied by high bioactivity.

  11. Electrophoretic deposition of nanostructured hydroxyapatite coating on AZ91 magnesium alloy implants with different surface treatments

    Science.gov (United States)

    Rojaee, Ramin; Fathi, Mohammadhossein; Raeissi, Keyvan

    2013-11-01

    Bio-absorbable magnesium (Mg) based alloys have been introduced as innovative orthopedic implants during recent years. It has been specified that rapid degradation of Mg based alloys in physiological environment should be restrained in order to be utilized in orthopedic trauma fixation and vascular intervention. In this developing field of healthcare materials, micro-arc oxidation (MAO), and MgF2 conversion coating were exploited as surface pre-treatment of AZ91 magnesium alloy to generate a nanostructured hydroxyapatite (n-HAp) coating via electrophoretic deposition (EPD) method. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and transmission electron microscopy (TEM) techniques were used to characterize the obtained powder and coatings. The potentiodynamic polarization tests were carried out to evaluate the corrosion behavior of the coated and uncoated specimens, and in vitro bioactivity evaluation were performed in simulated body fluid. Results revealed that the MAO/n-HAp coated AZ91 Mg alloy samples with a rough topography and lower corrosion current density leads to a lower Mg degradation rate accompanied by high bioactivity.

  12. Fatigue characteristics of sand-cast AZ91D magnesium alloy

    Directory of Open Access Journals (Sweden)

    Zhenming Li

    2017-03-01

    Full Text Available The fatigue characteristics of the AZ91D-T6 alloy samples taken from engine blocks have been investigated at 20 °C and elevated temperature (150 °C. The fatigue strength and cyclic stress amplitude of the alloy significantly decrease with the increase of the test temperature, although cyclic hardening occurs continuously until failure for both temperatures. With the increase of the temperature, the decreased fatigue life of the alloy tested at the same stress amplitude is mainly attributed to the decreased matrix strength and the increased hysteresis energies. Fatigue failure of the engine blocks made of AZ91D-T6 alloy is mainly controlled by casting defects. For the defect-free specimens, the crack initiation behavior is determined by the single-slip (20 °C and by environment-assisted cyclic slip (150 °C during fatigue, respectively. The low-cycle fatigue lives of the alloy can be predicted using the Coffin-Manson relation and Basquin laws, the three-parameter equation and the energy-based concepts, while the high-cycle fatigue lives of the alloy fitted well with the developed long crack life model and MSF life models.

  13. El blocao (y el bloqueo de José Díaz Fernández

    Directory of Open Access Journals (Sweden)

    Luis Fernando Bueno Morillas

    2015-06-01

    Full Text Available El blocao (1928 fue la primera novela de José Díaz Fernández. Supuso un éxito editorial insólito hasta entonces porque reunía tres características novedosas: una actitud crítica ante la guerra de Marruecos, una integración de las novedades vanguardistas en la que su autor llamó literatura de avanzada y un posicionamiento del intelectual al lado de las reivindicaciones del pueblo. Sin embargo, aunque publicó otra novela un año después (La Venus mecánica, un libro teórico en el que definía la literatura que él propugnaba y practicaba (El nuevo romanticismo y algunas narraciones breves, Díaz Fernández se bloqueó y dejó la literatura narrativa que tan buenas expectativas levantó. Analizaremos las posibles causas de ese bloqueo.

  14. Bernal Díaz del Castillo, la memoria y la representación

    Directory of Open Access Journals (Sweden)

    María Luisa Fischer

    2016-04-01

    Full Text Available En este trabajo se analizan los procedimientos narrativos que verosimilizan la versión de la historia que define Bernal Díaz del Castillo. Se analiza la función que en el total del relato cumplen los capítulos de largos listados que lo cierran y, especialmente, el capítulo CCVI, dedicado a los retratos indistinguibles de los capitanes españoles de la Nueva España. Se muestra cómo la memoria privilegiada del cronista está funcionando bajo el predicamento de una retórica -en este caso, la del retrato del héroe, de origen medieval- que disputa su lugar frente a la pretendida reconstrucción de la experiencia por la vía única de la memoria. This work analyse the narrative procedures which Bernal Díaz del Castillo uses to make his version of history appear to be probable. The function of the long lists at the end of the story and, especially of Chapter CCVI, containing the indistinguishable portraits of New Spain's Spanish capitains is explained. How the chronicler's privileged memory functions as a rhetorical category -in this case, that of the portrait of a medieval hero- who argues his case for the pretended reconstruction of an experience based only on memory is shown.

  15. Surface composite nanostructures of AZ91 magnesium alloy induced by high current pulsed electron beam treatment

    International Nuclear Information System (INIS)

    Li, M.C.; Hao, S.Z.; Wen, H.; Huang, R.F.

    2014-01-01

    High current pulsed electron beam (HCPEB) treatment was conducted on an AZ91 cast magnesium alloy with accelerating voltage 27 kV, energy density 3 J/cm 2 and pulse duration 2.5 μs. The surface microstructure was characterized by optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM) equipped with energy dispersive spectrometer (EDS), and transmission electron microscope (TEM). The surface corrosion property was tested with electrochemical method in 3.5 wt.% NaCl solution. It is found that after 1 pulse of HCPEB treatment, the initial eutectic α phase and Mg 17 Al 12 particles started to dissolve in the surface modified layer of depth ∼15 μm. When using 15 HCPEB pulses, the Al content in surface layer increased noticeably, and the phase structure was modified as composite nanostructures consisted of nano-grained Mg 3.1 Al 0.9 domains surrounded by network of Mg 17 Al 12 phase. The HCPEB treated samples showed an improved corrosion resistance with cathodic current density decreased by two orders of magnitude as compared to the initial AZ91 alloy.

  16. Mechanical properties and microstructural evaluation of AA1100 to AZ31 dissimilar friction stir welds

    Energy Technology Data Exchange (ETDEWEB)

    Azizieh, M., E-mail: azizieh@gmail.com [Department of Materials Science and Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz (Iran, Islamic Republic of); Sadeghi Alavijeh, A. [School of Mechatronic Systems Engineering, Simon Fraser University, 250-13450 102 Avenue, Surrey, BC V3T 0A3 (Canada); Abbasi, M. [High Temperature Energy Materials, Korea Institute of Science and Technology, Seoul, 136-791 (Korea, Republic of); Balak, Z. [Department of Materials Science and Engineering, Ahvaz Branch, Islamic Azad University, Ahvaz (Iran, Islamic Republic of); Kim, H.S. [Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang, 790-784 (Korea, Republic of)

    2016-02-15

    In this paper, microstructure and mechanical properties of dissimilar friction stir welds of AA1100 and AZ31 were investigated to understand the effects of rotational and travel speed as well as pin position. The tensile results of welded samples revealed that the sound welds were formed when the stirring pin deviated from the centreline to the AZ31 side. The X-ray diffraction shows that Al{sub 3}Mg{sub 2} and Al{sub 12}Mg{sub 17} intermetallics formation occurs in the stir zone during the welding process. High hardness of these intermetallic phases increased the hardness of the stir zone to 110 Hv. The best tensile results were obtained in the sample processed in the range of 28–32 (rev/mm) rotational to travel speed ratio. - Highlights: • For Al to Mg friction stir welding, tool offset must be to Mg side. • There is an optimum rotational speed for obtain the highest strength. • Intermetallics form in any welding condition. • The volume fraction of intermetallic is directly related to FSW peak temperature.

  17. Influence of Friction Stir Welding on Mechanical Properties of Butt Joints of AZ61 Magnesium Alloy

    Directory of Open Access Journals (Sweden)

    Seung-Ju Sun

    2017-01-01

    Full Text Available In this study, the effect of heat input on the mechanical properties and fracture behaviors of AZ61 magnesium alloy joints has been studied. Magnesium alloy AZ61 plates with thickness of 5 mm were welded at different ratios of tool rotational speed to welding speed (ω/ν. The average ultimate tensile strength of all weld conditions satisfying a ω/ν ratio of 3 reached 100% of the strength of the base material. Fractures occurred at the interface between the thermomechanical affected zone at advancing side and the stir zone in all welded specimens. From the scanning electron microscope and electron backscatter diffraction analysis, it was determined that the interface between the thermomechanical affected zone and the stir zone, which is the region where the grain orientation changes, was the weakest part; the advancing side region was relatively weaker than the retreating side region because the grain orientation change occurred more dramatically in the advancing side region.

  18. ANALISIS DAN PERANCANGAN ARSITEKTUR SISTEM OTENTIKASI TERINTEGRASI ANTARA PLATFORM LINUX, WINDOWS 2000, DAN NOVELL NETWARE: STUDI KASUS JURUSAN TEKNIK INFORMATIKA FTIF ITS

    Directory of Open Access Journals (Sweden)

    Rully Soelaiman

    2003-07-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Jurusan Teknik Infomatika merupakan suatu organisasi yang menggunakan jaringan komputer yang diakses dari beberapa domain dan menggunakan sistem operasi terpisah. Masing-masing sistem tersebut menggunakan pengelolaan autentikasi yang terpisah, dengan kenyataan bahwa seharusnya dapat diakses oleh setiap anggota organisasi ini. Kebutuhan pengguna dan pengelola jaringan akan efisiensi pemakaian informasi autentikasi menjadi permasalahan yang akan dibahasa dana makalah ini. Pada makalah ini, dilakukan analisis kemungkinan dilakukannya otentikasi terintegrasi pada jaringan komputer Teknik Informatika yang menggunakan Windows 2000, Linux, dan Novell Netware. Analisis dilakukan dengan meninjau kemampuan integrasi direktori, metode otentikasi, dan kerjasama dengan sistem lain. Dari hasil pemetaan terhadap kebutuhan dan ketersediaan sumber daya teknologi pada jurusan, dipilih solusi otentikasi menggunakan Samba dan OpenLDAP untuk melayani permintaan otentikasi dari Windows 2000 dan Linux. Uji coba telah dilakukan untuk otentikasi client Windows 2000 dan Linux , mencakup login dari masing-masing sistem operasi, domain yang berbeda, menggunakan satu username dan password. Uji coba juga dilakukan terhadap proses

  19. Histone variant H2A.Z antagonizes the positive effect of the transcriptional activator CPC1 to regulate catalase-3 expression under normal and oxidative stress conditions.

    Science.gov (United States)

    Dong, Qing; Wang, Yajun; Qi, Shaohua; Gai, Kexin; He, Qun; Wang, Ying

    2018-05-05

    In eukaryotes, deposition of the histone variant H2A.Z into nucleosomes through the chromatin remodeling complex, SWR1, is a crucial step in modulating gene transcription. Recently, H2A.Z has been shown to control the expression of responsive genes, but the underlying mechanism of how H2A.Z responds to physiological stimuli is not well understood. Here, we reveal that, in Neurospora crassa, H2A.Z is a negative regulator of catalase-3 gene, which is responsible for resistance to oxidative stress. H2A.Z represses cat-3 gene expression through direct incorporation at cat-3 locus in a SWR1 complex dependent pathway. Notably, loss of H2A.Z or SWR1 subunits leads to increased binding of a transcription factor, CPC1, at cat-3 locus. Additionally, introduction of plasmids containing gene encoding H2A.Z or SWR1 complex subunits into wild-type strains decreased CAT-3 expression, indicating that H2A.Z counteracts the positive effect of CPC1 to achieve low level cat-3 expression under non-inductive condition. Furthermore, upon oxidative stress, H2A.Z is rapidly evicted from cat-3 locus for the recruitment of CPC1, resulting in robust and full cat-3 gene expression in response to external stimuli. Collectively, this study strongly demonstrates that H2A.Z antagonizes the function of transcription factor to regulate responsive gene transcription under normal conditions and to poise for gene full activation under oxidative stress. Copyright © 2018. Published by Elsevier Inc.

  20. Development of mechanical properties in a CaO added AZ31 magnesium alloy processed by equal-channel angular pressing

    International Nuclear Information System (INIS)

    Bae, Seong-Hwan; Jung, Ki Ho; Shin, Young-Chul; Yoon, Duk Jae; Kawasaki, Megumi

    2016-01-01

    Processing through the application of equal-channel angular pressing (ECAP) is recognized as one of the attractive severe plastic deformation techniques where the processed bulk metals generally achieve ultrafine-grained microstructure leading to improved physical characteristics and mechanical properties. Magnesium has received much attention to date for its lightweight, high strength and excellent elasticity. Mg alloys with addition of CaO is reported to provide the successful casting procedure without usage of greenhouse gas, SF 6 , whereas it is generally used for preventing the oxidation of Mg during casting. In the present investigation, a CaO added AZ31 (AZ31-CaO) magnesium alloy was processed by ECAP at elevated temepratures with a few steps of reduction which result in significant grain refinement to ~ 1.5 μm after 6 passes. Compression testing at room temperature demonstrated the AZ31-CaO alloy after ECAP showed enhanced yield strength more than the as-processed commercial AZ31 alloy while both alloys maintained ductility in spite of significant reduction in grain size. The improved strength in the AZ31-CaO alloy was attributed to the formation of fine Al 2 Ca precipitates which experience breaking-up through ECAP and accelerate the microstructural refinement. Moreover, the preservation of ductility was attributed to the enhancement of strain hardening capability in the AZ31 alloy at room temperature. This study discusses the feasibility of using ECAP to improve both strength and ductility on magnesium alloys by applying the diagram describing the paradox of strength and ductility. - Highlights: • AZ31 and AZ31-CaO magnesium alloys were processed by ECAP up to 6 passes. • AZ31-CaO alloy after ECAP showed improved yield strength without losing ductility. • CaO in AZ31 forms fine Al 2 Ca accelerating microstructural refinement during ECAP. • Feasibility of using ECAP was shown to improve both strength and ductility in Mg.

  1. Influencia de compuestos azúcares y no azúcares en la calidad industrial de caña de azúcar en Tucumán (R. Argentina: Parte 1: caña limpia y despuntada Influence of sugar and nonsugar compounds on sugarcane industrial quality in Tucumán (Argentine Republic

    Directory of Open Access Journals (Sweden)

    B. Silvia Zossi

    Full Text Available Se estudió la concentración de compuestos azúcares y no azúcares, especialmente los que influyen en la formación del color y otros que inciden en el proceso industrial de producción de azúcar blanco directo, de las cuatro variedades comerciales de caña más difundidas en Tucumán (R. Argentina: TUCCP 77-42, LCP 85-384, CP 65-357 y RA 87-3. Estos ensayos fueron realizados durante las zafras 2004 a 2007 en caña limpia y despuntada. Los parámetros analizados fueron: extracción de jugo, Brix %, pol % en jugo y en caña, sacarosa y azúcar recuperable. Se estudiaron no azúcares inorgánicos, tales como cenizas, fosfato y sílice, y no azúcares orgánicos: fibra, almidón, compuestos antocianos y fenoles, nitrógeno amínico, ácidos cis y trans-aconítico, "indicator value" y color. De las cuatro variedades analizadas, la que mejor comportamiento presentó para producir azúcar blanco directo fue LCP 85-384, por su alto contenido en sacarosa y bajo contenido de componentes no azúcares. El segundo lugar le correspondió a la variedad RA 87-3, seguida por CP 65-357 y TUCCP 77-42.The concentration of sugar and nonsugar compounds, especially those which play a part in colour formation and others which affect direct white sugar manufacturing process, was studied in the four commercial cane varieties most widely grown in Tucumán (Argentine Republic: TUCCP 77-42, LCP 85-384, CP 65-357 and RA 87-3. Trials with clean cane were conducted during the 2004-2007 harvests. Analyzed parameters were: juice extraction, Brix %, pol % in juice and cane, sucrose and sugar recovery. Inorganic nonsugar compounds, such as ash, phosphate and silica, as well as organic ones, such as fibre, starch, anthocyanin and phenolic compounds, amino nitrogen, cis and trans-aconitic acids, indicator value and colour, were studied. Results showed that LCP 85-384 variety had the best factory performance to produce direct white sugar because of its high sucrose and low

  2. Analysis of the Deformability of Two-Layer Materials AZ31/Eutectic / Analiza Możliwości Odkształcania Plastycznego Materiału Dwuwarstwowego AZ31/Eutektyka

    Directory of Open Access Journals (Sweden)

    Mola R.

    2015-12-01

    Full Text Available The paper present the results of physical simulation of the deformation of the two-layered AZ31/eutectic material using the Gleeble 3800 metallurgical processes simulator. The eutectic layer was produced on the AZ31 substrate using thermochemical treatment. The specimens of AZ31 alloy were heat treated in contact with aluminium powder at 445°C in a vacuum furnace. Depending on the heating time, Al-enriched surface layers with a thickness of 400, 700 and 1100 μm were fabricated on a substrate which was characterized by an eutectic structure composed of the Mg17Al12 phase and a solid solution of aluminium in magnesium. In the study, physical simulation of the fabricated two-layered specimens with a varying thickness of the eutectic layer were deformed using the plane strain compression test at various values of strain rates. The testing results have revealed that it is possible to deform the two-layered AZ31/eutectic material at low strain rates and small deformation values.

  3. The extrusion of AZ-series magnesium alloys - extending the processing limits by hydrostatic extrusion; Erweiterung der Prozessgrenzen beim Strangpressen von Magnesiumknetlegierungen der AZ-Reihe durch das hydrostatische Strangpressverfahren

    Energy Technology Data Exchange (ETDEWEB)

    Swiostek, J. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Werkstofforschung

    2008-12-04

    The present study is concerned with the analysis of the influence of hydrostatic extrusion on the microstructural development and mechanical properties of extruded profiles of the AZ-series magnesium alloys. This work also deals with the correlation between the microstructure and resulting mechanical properties for the case extruded profiles. (orig.)

  4. Analisis Beban Kerja untuk Menentukan Jumlah Optimal Karyawan dan Pemetaan Kompetensi Karyawan Berdasar Pada Job Description (Studi Kasus : Jurusan Teknik Industri, ITS, Surabaya

    Directory of Open Access Journals (Sweden)

    Raras Mayang Arsi

    2012-09-01

    Full Text Available Beban kerja yang harus ditanggung dalam suatu unit organisasi erat kaitannya dengan efisiensi dan efektivitas suatu perusahaan. Hal ini dikarenakan beban kerja tersebut termasuk pada pengaturan sumber daya manusia yang merupakan sumber daya penting dalam perusahaan. Banyak cara yang dapat dilakukan dalam hal efisiensi sumber daya manusia, antara lain adalah dengan lebih mengoptimalkan jumlah karyawan agar melakukan aktivitas secara tepat. ITS Surabaya, sebagai salah satu perguruan tinggi terkemuka di Indonesia, juga tidak lepas dari permasalahan beban kerja ini. Adanya empat kali perubahan statuta dan penyesuaian mengenai Organisai Tata Kelola (OTK, membuat pihak ITS harus melakukan reformasi birokrasi dan reformasi organisai untuk mengembangkan ITS kedepannya. Hal ini berdampak pada banyaknya perubahan job description yang dilakukan oleh bidang-bidang yang ada di ITS, termasuk yang menjadi objek penelitian ini yaitu Jurusan Teknik Industri ITS, sehingga beban kerja yang ditanggung oleh setiap karyawan di setiap bidang tidak sesuai dengan jumlah karyawan pada bidang itu sendiri. Oleh karena itu diperlukan suatu analisis pengukuran beban kerja untuk menentukan jumlah optimal karyawan yang seharusnya dibutuhkan oleh setiap bidang. Pada penelitian ini nantinya, yang akan digunakan adalah metode perhitungan beban tugas per jabatan sesuai dengan KEP/75/M.PAN/7/2004 dan NASA-TLX.

  5. Warm Deep Drawing of Rectangular Parts of AZ31 Magnesium Alloy Sheet Adopting Variable Blank Holder Force

    International Nuclear Information System (INIS)

    Peng Yinghong; Chang Qunfeng; Li Dayong; Zeng Xiaoqin

    2007-01-01

    AZ31 magnesium alloy sheet with good shape and formability is fabricated by warm cross rolling. Uniaxial tensile tests are conducted using a Gleeble 3500 thermal - mechanical simulator, and the mechanical properties of AZ31 magnesium alloy sheet are analyzed. A warm deep drawing process of square part is also simulated by the finite element method. The influences of blank holder force on the formability are numerically investigated. A double-action hydraulic press that can realize adjustable blank holder forces is developed and its working principle and control system are introduced. Some warm deep drawing experiments of square parts of AZ31 magnesium alloy sheet are also performed. Different variation schemes of the blank holder force with the stroke of the punch are tested, and the experiment results are compared. Results show that the suitable blank holder force variation scheme is a ladder curve with the punch stroke. Adopting the variable blank holder force technique can improve 13.2% of the drawing depth of square parts of AZ31 magnesium alloy sheet

  6. Effect of Mucin and Bicarbonate Ion on Corrosion Behavior of AZ31 Magnesium Alloy for Airway Stents

    Directory of Open Access Journals (Sweden)

    Yongseok Jang

    2014-08-01

    Full Text Available The biodegradable ability of magnesium alloys is an attractive feature for tracheal stents since they can be absorbed by the body through gradual degradation after healing of the airway structure, which can reduce the risk of inflammation caused by long-term implantation and prevent the repetitive surgery for removal of existing stent. In this study, the effects of bicarbonate ion (HCO3− and mucin in Gamble’s solution on the corrosion behavior of AZ31 magnesium alloy were investigated, using immersion and electrochemical tests to systematically identify the biodegradation kinetics of magnesium alloy under in vitro environment, mimicking the epithelial mucus surfaces in a trachea for development of biodegradable airway stents. Analysis of corrosion products after immersion test was performed using scanning electron microscopy (SEM, energy dispersive X-ray spectroscopy (EDX and X-ray diffraction (XRD. Electrochemical impedance spectroscopy (EIS was used to identify the effects of bicarbonate ions and mucin on the corrosion behavior of AZ31 magnesium alloys with the temporal change of corrosion resistance. The results show that the increase of the bicarbonate ions in Gamble’s solution accelerates the dissolution of AZ31 magnesium alloy, while the addition of mucin retards the corrosion. The experimental data in this work is intended to be used as foundational knowledge to predict the corrosion behavior of AZ31 magnesium alloy in the airway environment while providing degradation information for future in vivo studies.

  7. Preparation and characterization of inorganic and organic coatings on AZ91D magnesium alloy with electroless plating pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, S.Y.; Li, Q.; Zhang, H.X.; Wang, S.Y.; Liu, F. [School of Chemistry and Chemical Engineering, Southwest University Chongqing, 400715 (China); Yang, X.K. [School of Materials Science and Engineering, Southwest University Chongqing, 400715 (China)

    2011-09-15

    In this paper, a protective coating scheme was applied for the corrosion protection of AZ91D magnesium alloy. Electroless Ni coating (EN coating) as bottom layer, electrodeposited Ni coating (ENN coating), and silane-based coating (ENS coating) as top layer, respectively, were successfully prepared on AZ91D magnesium alloy by combination techniques. Scanning electron microscopy and X-ray diffraction were employed to investigate the surface and phase structure of coatings, respectively. The electrochemical corrosion behaviors of coatings in neutral 3.5 wt% NaCl solution were evaluated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. The corrosion testing showed that the three kinds of coatings all could provide corrosion protection for AZ91D magnesium alloy to a certain extent, and the corrosion resistance of ENN and ENS was superior to EN. In order to further study the corrosion protection properties of ENN and ENS, a comparative investigation on the evolution of EIS of ENN and ENS was carried out by dint of immersion test in neutral 3.5 wt% NaCl solution. The results indicated that, compared with ENN, the ENS could provide longer corrosion protection for AZ91D magnesium alloy. It is significant to determine the barrier effect of each coating, which could provide reference for industry applications. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Effect of Mucin and Bicarbonate Ion on Corrosion Behavior of AZ31 Magnesium Alloy for Airway Stents.

    Science.gov (United States)

    Jang, Yongseok; Owuor, Daniel; Waterman, Jenora T; White, Leon; Collins, Boyce; Sankar, Jagannathan; Gilbert, Thomas W; Yun, Yeoheung

    2014-08-15

    The biodegradable ability of magnesium alloys is an attractive feature for tracheal stents since they can be absorbed by the body through gradual degradation after healing of the airway structure, which can reduce the risk of inflammation caused by long-term implantation and prevent the repetitive surgery for removal of existing stent. In this study, the effects of bicarbonate ion (HCO₃ - ) and mucin in Gamble's solution on the corrosion behavior of AZ31 magnesium alloy were investigated, using immersion and electrochemical tests to systematically identify the biodegradation kinetics of magnesium alloy under in vitro environment, mimicking the epithelial mucus surfaces in a trachea for development of biodegradable airway stents. Analysis of corrosion products after immersion test was performed using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). Electrochemical impedance spectroscopy (EIS) was used to identify the effects of bicarbonate ions and mucin on the corrosion behavior of AZ31 magnesium alloys with the temporal change of corrosion resistance. The results show that the increase of the bicarbonate ions in Gamble's solution accelerates the dissolution of AZ31 magnesium alloy, while the addition of mucin retards the corrosion. The experimental data in this work is intended to be used as foundational knowledge to predict the corrosion behavior of AZ31 magnesium alloy in the airway environment while providing degradation information for future in vivo studies.

  9. 75 FR 2133 - Construction and Operation of the Quartzsite Solar Energy Project, La Paz County, AZ (DOE/EIS-0440)

    Science.gov (United States)

    2010-01-14

    ... Quartzsite Solar Energy Project, La Paz County, AZ (DOE/EIS-0440) AGENCY: Western Area Power Administration... proposed Quartzsite Solar Energy Project (Project) in La Paz County, near Quartzsite, Arizona. Quartzsite Solar Energy, LLC (QSE) has applied to Western to interconnect the proposed Project to Western's power...

  10. Microstructure investigation and first-principle analysis of die-cast AZ91 alloy with calcium addition

    International Nuclear Information System (INIS)

    Lin, L.; Wang, F.; Yang, L.; Chen, L.J.; Liu, Z.; Wang, Y.M.

    2011-01-01

    Highlights: → Die-cast AZ91 with Ca addition was investigated experimentally and theoretically. → Precipitation sequence was confirmed with increasing Ca addition. → Phase stability difference was verified by first-principle calculation. → Valence configurations were associated with alloying effects of Al, Mg and Ca. - Abstract: In order to get improved mechanical properties of die-cast AZ91 alloy under elevated temperatures, Ca element was added as a cost-effective alloying constituent. It appeared that minor Ca addition less than 0.5 wt% would result in no apparent change in microstructure, but the tensile strength at elevated temperatures was improved considerably. When increasing Ca addition to more than 1.0 wt%, Al 2 Ca phase will precipitate during solidification, no Mg 2 Ca phase was discovered. Homogeneous microstructure and high temperature stability in tensile strength of die-cast AZ91 alloy with Ca addition was mainly attributed to the precipitation of Al 2 Ca phase, which considerably refined the bulky β-Mg 17 Al 12 phase distributed originally at the grain boundaries of die-cast AZ91 alloy with no Ca addition. The priority of Al 2 Ca phase compared to Mg 2 Ca phase in precipitation sequence was verified by first-principle calculation of their cohesive energy and formation enthalpy, and can also be associated with more bounding electrons between Al and Ca atoms.

  11. Influence of Sulfate-Reducing Bacteria on the Corrosion Residual Strength of an AZ91D Magnesium Alloy

    Science.gov (United States)

    Zhu, Xianyong; Liu, Yaohui; Wang, Qiang; Liu, Jiaan

    2014-01-01

    In this paper, the corrosion residual strength of the AZ91D magnesium alloy in the presence of sulfate-reducing bacteria is studied. In the experiments, the chemical composition of corrosion film was analyzed by a scanning electron microscope with energy dispersive X-ray spectroscopy. In addition, a series of instruments, such as scanning electronic microscope, pH-meter and an AG-10TA materials test machine, were applied to test and record the morphology of the corrosion product, fracture texture and mechanical properties of the AZ91D magnesium alloy. The experiments show that the sulfate-reducing bacteria (SRB) play an important role in the corrosion process of the AZ91D magnesium alloy. Pitting corrosion was enhanced by sulfate-reducing bacteria. Corrosion pits are important defects that could lead to a significant stress concentration in the tensile process. As a result, sulfate-reducing bacteria influence the corrosion residual strength of the AZ91D magnesium alloy by accelerating pitting corrosion. PMID:28788236

  12. ARSENIC REMOVAL FROM DRINKING WATER BY ADSORPTIVE MEDIA USEPA DEMONSTRATION PROJECT AT VALLEY VISTA, AZ SIX-MONTH EVALUATION REPORT

    Science.gov (United States)

    This report documents the activities performed and the results obtained from the first six months of the EPA arsenic removal technology demonstration project at the Arizona Water Company (AWC) facility in Sedona, AZ, commonly referred to as Valley Vista. The main objective of the...

  13. ARSENIC REMOVAL FROM DRINKING WATER BY ADSORPTIVE MEDIA, USEPA DEMONSTRATION PROJECT AT RIMROCK, AZ, SIX-MONTH EVALUATION REPORT

    Science.gov (United States)

    This report documents the activities performed during and the results obtained from the first six months of the arsenic removal treatment technology demonstration project at Rimrock, AZ. The objectives of the project are to evaluate the effectiveness of AdEdge Arsenic Package Uni...

  14. A Study on Compressive Anisotropy and Nonassociated Flow Plasticity of the AZ31 Magnesium Alloy in Hot Rolling

    Directory of Open Access Journals (Sweden)

    Guoqiang Wang

    2014-01-01

    Full Text Available Effect of anisotropy in compression is studied on hot rolling of AZ31 magnesium alloy with a three-dimensional constitutive model based on the quadratic Hill48 yield criterion and nonassociated flow rule (non-AFR. The constitutive model is characterized by compressive tests of AZ31 billets since plastic deformations of materials are mostly caused by compression during rolling processes. The characterized plasticity model is implemented into ABAQUS/Explicit as a user-defined material subroutine (VUMAT based on semi-implicit backward Euler's method. The subroutine is employed to simulate square-bar rolling processes. The simulation results are compared with rolled specimens and those predicted by the von Mises and the Hill48 yield function under AFR. Moreover, strip rolling is also simulated for AZ31 with the Hill48 yield function under non-AFR. The strip rolling simulation demonstrates that the lateral spread generated by the non-AFR model is in good agreement with experimental data. These comparisons between simulation and experiments validate that the proposed Hill48 yield function under non-AFR provides satisfactory description of plastic deformation behavior in hot rolling for AZ31 alloys in case that the anisotropic parameters in the Hill48 yield function and the non-associated flow rule are calibrated by the compressive experimental results.

  15. Pump Jet Mixing and Pipeline Transfer Assessment for High-Activity Radioactive Wastes in Hanford Tank 241-AZ-102

    Energy Technology Data Exchange (ETDEWEB)

    Y Onishi; KP Recknagle; BE Wells

    2000-08-09

    The authors evaluated how well two 300-hp mixer pumps would mix solid and liquid radioactive wastes stored in Hanford double-shell Tank 241-AZ-102 (AZ-102) and confirmed the adequacy of a three-inch (7.6-cm) pipeline system to transfer the resulting mixed waste slurry to the AP Tank Farm and a planned waste treatment (vitrification) plant on the Hanford Site. Tank AZ-102 contains 854,000 gallons (3,230 m{sup 3}) of supernatant liquid and 95,000 gallons (360 m{sup 3}) of sludge made up of aging waste (or neutralized current acid waste). The study comprises three assessments: waste chemistry, pump jet mixing, and pipeline transfer. The waste chemical modeling assessment indicates that the sludge, consisting of the solids and interstitial solution, and the supernatant liquid are basically in an equilibrium condition. Thus, pump jet mixing would not cause much solids precipitation and dissolution, only 1.5% or less of the total AZ-102 sludge. The pump jet mixing modeling indicates that two 300-hp mixer pumps would mobilize up to about 23 ft (7.0 m) of the sludge nearest the pump but would not erode the waste within seven inches (0.18 m) of the tank bottom. This results in about half of the sludge being uniformly mixed in the tank and the other half being unmixed (not eroded) at the tank bottom.

  16. 76 FR 15936 - Designation for the Owensboro, KY; Bloomington, IL; Iowa Falls, IA; Casa Grande, AZ; Fargo, ND...

    Science.gov (United States)

    2011-03-22

    ... DEPARTMENT OF AGRICULTURE Grain Inspection, Packers and Stockyards Administration Designation for the Owensboro, KY; Bloomington, IL; Iowa Falls, IA; Casa Grande, AZ; Fargo, ND; Grand Forks, ND; and Plainview, TX Areas AGENCY: Grain Inspection, Packers and Stockyards Administration, USDA. ACTION: Notice...

  17. 78 FR 43850 - Opportunity for Designation in Owensboro, KY; Bloomington, IL; Iowa Falls, IA; Casa Grande, AZ...

    Science.gov (United States)

    2013-07-22

    ... DEPARTMENT OF AGRICULTURE Grain Inspection, Packers and Stockyards Administration Opportunity for Designation in Owensboro, KY; Bloomington, IL; Iowa Falls, IA; Casa Grande, AZ; Fargo, ND; Grand Forks, ND and Plainview, TX; Areas; Request for Comments on the Official Agencies Servicing These Areas AGENCY: Grain...

  18. 77 FR 75144 - Foreign-Trade Zone 277-Western Maricopa County, AZ; Application for Expansion; (New Magnet Site...

    Science.gov (United States)

    2012-12-19

    ... Maricopa County, AZ; Application for Expansion; (New Magnet Site) Under Alternative Site Framework An... additional new magnet sites in western Maricopa County, Arizona and request usage-driven designation for an..., Arizona. The current zone project includes the following magnet sites: Site 1 (230.25 acres)--within the...

  19. Pump Jet Mixing and Pipeline Transfer Assessment for High-Activity Radioactive Wastes in Hanford Tank 241-AZ-102

    International Nuclear Information System (INIS)

    Onishi, Y.; Recknagle, K.P.; Wells, B.E.

    2000-01-01

    The authors evaluated how well two 300-hp mixer pumps would mix solid and liquid radioactive wastes stored in Hanford double-shell Tank 241-AZ-102 (AZ-102) and confirmed the adequacy of a three-inch (7.6-cm) pipeline system to transfer the resulting mixed waste slurry to the AP Tank Farm and a planned waste treatment (vitrification) plant on the Hanford Site. Tank AZ-102 contains 854,000 gallons (3,230 m 3 ) of supernatant liquid and 95,000 gallons (360 m 3 ) of sludge made up of aging waste (or neutralized current acid waste). The study comprises three assessments: waste chemistry, pump jet mixing, and pipeline transfer. The waste chemical modeling assessment indicates that the sludge, consisting of the solids and interstitial solution, and the supernatant liquid are basically in an equilibrium condition. Thus, pump jet mixing would not cause much solids precipitation and dissolution, only 1.5% or less of the total AZ-102 sludge. The pump jet mixing modeling indicates that two 300-hp mixer pumps would mobilize up to about 23 ft (7.0 m) of the sludge nearest the pump but would not erode the waste within seven inches (0.18 m) of the tank bottom. This results in about half of the sludge being uniformly mixed in the tank and the other half being unmixed (not eroded) at the tank bottom

  20. Role of manganese on the grain refining efficiency of AZ91D magnesium alloy refined by Al4C3

    International Nuclear Information System (INIS)

    Liu Shengfa; Zhang Yuan; Han Hui

    2010-01-01

    A novel Mg-50% Al 4 C 3 (hereafter in wt.%) master alloy has been developed by powder in situ synthesis process, the role of manganese on the grain refining efficiency of AZ91D magnesium alloy refined by this master alloy has been investigated. X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS) results show the existence of Al 4 C 3 particles in this master alloy. After addition of 0.6% Al 4 C 3 or combined addition of 0.6% Al 4 C 3 and 0.27% Mn, the average grain size of AZ91D decreased dramatically from 360 μm to 210 μm, and from 360 μm to130 μm, respectively. However, no further refinement of grain size was achieved with additional amount of Mn exceeding 0.27% for AZ91D alloy refined by 0.6% Al 4 C 3 in the present investigation. Al-C-O-Mn-Fe-rich intermetallic particles with an Al-C-O-rich coating film, often observed in the central region of magnesium grains of the AZ91D alloy treated by the combination of Al 4 C 3 and Mn, are proposed to be the potent nucleating substrates for primary α-Mg.

  1. Microstructure characteristics and effect of aging process on the mechanical properties of squeeze-cast AZ91 alloy

    International Nuclear Information System (INIS)

    Han, G.M.; Han, Z.Q.; Luo, A.A.; Liu, B.C.

    2015-01-01

    Highlights: • Characterization of three-dimensional morphologies of precipitates using AFM. • Quantitative microstructure of aged squeeze-cast AZ91 alloy. • The non-uniform continuous precipitation during aging of squeeze-cast AZ91 alloy. • The relationship between microstructure and property of aged squeeze-cast AZ91 alloy. - Abstract: Quantitative microstructure information is critical to modeling and prediction of mechanical properties of structural components. In this study, the microstructure characteristics of aged squeeze-cast AZ91 alloy were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM) analyses. Particularly, a study of the three-dimensional morphology of continuous precipitation during heat treatment was carried out using a combination of TEM and AFM. The results showed that a typical precipitate consisted of three kinds of faces, namely, broad, side, and end faces. The precipitate also presented a lath-shaped morphology with lozenge ends. Combined SEM and TEM analyses revealed quantitative information on the sizes and area number densities of precipitates after aging at different temperatures with different times. In general, the length and width of precipitates increased more rapidly than thickness during aging. The area number density initially increased and then slowly decreased because of coarsening. Furthermore, a special microstructure characteristic of the non-uniform continuous precipitation during aging was investigated using electron probe microanalysis (EPMA). The relationship between hardness response and yield strength was established

  2. AZ-101 Mixer Pump Demonstration and Tests Data Management Analysis Plan

    Energy Technology Data Exchange (ETDEWEB)

    DOUGLAS, D.G.

    2000-02-22

    This document provides a plan for the analysis of the data collected during the AZ-101 Mixer Pump Demonstration and Tests. This document was prepared after a review of the AZ-101 Mixer Pump Test Plan (Revision 4) [1] and other materials. The plan emphasizes a structured and well-ordered approach towards handling and examining the data. This plan presumes that the data will be collected and organized into a unified body of data, well annotated and bearing the date and time of each record. The analysis of this data will follow a methodical series of steps that are focused on well-defined objectives. Section 2 of this plan describes how the data analysis will proceed from the real-time monitoring of some of the key sensor data to the final analysis of the three-dimensional distribution of suspended solids. This section also identifies the various sensors or sensor systems and associates them with the various functions they serve during the test program. Section 3 provides an overview of the objectives of the AZ-101 test program and describes the data that will be analyzed to support that test. The objectives are: (1) to demonstrate that the mixer pumps can be operated within the operating requirements; (2) to demonstrate that the mixer pumps can mobilize the sludge in sufficient quantities to provide feed to the private contractor facility, and (3) to determine if the in-tank instrumentation is sufficient to monitor sludge mobilization and mixer pump operation. Section 3 also describes the interim analysis that organizes the data during the test, so the analysis can be more readily accomplished. Section 4 describes the spatial orientation of the various sensors in the tank. This section is useful in visualizing the relationship of the Sensors in terms of their location in the tank and how the data from these sensors may be related to the data from other sensors. Section 5 provides a summary of the various analyses that will be performed on the data during the test

  3. Effect of fiber laser parameters on laser welded AZ31B Magnesium alloys

    Directory of Open Access Journals (Sweden)

    Mat Salleh Naqiuddin

    2017-01-01

    Full Text Available Recently, the usage of Magnesium (Mg alloys has been hugely applied in the industrial application such as in automotive, marine, and electronic due to its advantages of recyclability and lightweight. This alloys required low heat input to be weld since it is easily evaporated due to the Magnesium Oxide (MgO at the surface and it also possesses lower melting point compared to steel. Laser welding is more convenient to weld Mg alloys due to its high power and lower heat input. AZ31B was selected since it has strong mechanical properties among others Mg alloys due to the major alloying elements; Aluminium (Al and Zinc (Zn. Low power fiber laser machine with wavelength of 900 nm was used in this experiment. The intention of this work was to investigate the effect of low power fiber laser parameters and effect of shielding gas on weld penetration and microstructure. Another aim in this work was to produce the joint for this thin sheets metal. Penetration depth and microstructure evaluation were emphasized in the analysis section. Bead-on-Plate (BOP and laser lap welding was conducted on AZ31B with thicknesses of 1.0 mm and 0.6 mm for feasibility study using pulsed wave (PW mode. Defocusing features was used in order to find better focal position, which has less occurrence of evaporation (underfill. The effect of different angle of irradiation was also investigated. Two types of shielding gases, Argon (Ar and Nitrogen (N2 were used in order to study the effect of shielding gas. Lastly, the effect of pulsed energy on penetration types and depth of BOP welded samples was investigated. Focus point was found at focal length of 156 mm with 393.75 μm. For BOP experiment, higher pulsed energy used contributes to melt through defect. Meanwhile, Ns shielding gas proved to be better shielding gas in laser welding the AZ31B. Higher angle of irradiation could reduce the underfill defect. Fillet Lap joint of similar metal was successfully done where 2.0 J of

  4. AZ-101 Mixer Pump Demonstration and Tests: Data Management (Analysis) Plan

    International Nuclear Information System (INIS)

    DOUGLAS, D.G.

    2000-01-01

    This document provides a plan for the analysis of the data collected during the AZ-101 Mixer Pump Demonstration and Tests. This document was prepared after a review of the AZ-101 Mixer Pump Test Plan (Revision 4) [1] and other materials. The plan emphasizes a structured and well-ordered approach towards handling and examining the data. This plan presumes that the data will be collected and organized into a unified body of data, well annotated and bearing the date and time of each record. The analysis of this data will follow a methodical series of steps that are focused on well-defined objectives. Section 2 of this plan describes how the data analysis will proceed from the real-time monitoring of some of the key sensor data to the final analysis of the three-dimensional distribution of suspended solids. This section also identifies the various sensors or sensor systems and associates them with the various functions they serve during the test program. Section 3 provides an overview of the objectives of the AZ-101 test program and describes the data that will be analyzed to support that test. The objectives are: (1) to demonstrate that the mixer pumps can be operated within the operating requirements; (2) to demonstrate that the mixer pumps can mobilize the sludge in sufficient quantities to provide feed to the private contractor facility, and (3) to determine if the in-tank instrumentation is sufficient to monitor sludge mobilization and mixer pump operation. Section 3 also describes the interim analysis that organizes the data during the test, so the analysis can be more readily accomplished. Section 4 describes the spatial orientation of the various sensors in the tank. This section is useful in visualizing the relationship of the Sensors in terms of their location in the tank and how the data from these sensors may be related to the data from other sensors. Section 5 provides a summary of the various analyses that will be performed on the data during the test

  5. Systematic understanding of corrosion behavior of plasma electrolytic oxidation treated AZ31 magnesium alloy using a mouse model of subcutaneous implant.

    Science.gov (United States)

    Jang, Yongseok; Tan, Zongqing; Jurey, Chris; Collins, Boyce; Badve, Aditya; Dong, Zhongyun; Park, Chanhee; Kim, Cheol Sang; Sankar, Jagannathan; Yun, Yeoheung

    2014-12-01

    This study was conducted to identify the differences between corrosion rates, corrosion types, and corrosion products in different physiological environments for AZ31 magnesium alloy and plasma electrolytic oxidation (PEO) treated AZ31 magnesium alloy. In vitro and in vivo tests were performed in Hank's Balanced Salt Solution (HBSS) and mice for 12 weeks, respectively. The corrosion rates of both AZ31 magnesium alloy and PEO treated AZ31 magnesium alloy were calculated based on DC polarization curves, volume of hydrogen evolution, and the thickness of corrosion products formed on the surface. Micro X-ray computed tomography (Micro-CT), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) were used to analyze morphological and chemical characterizations of corrosion products. The results show that there is more severe localized corrosion after in vitro test in HBSS; however, the thicknesses of corrosion products formed on the surface for AZ31 magnesium alloy and PEO treated AZ31 magnesium alloy in vivo were about 40% thicker than the thickness of corrosion products generated in vitro. The ratio of Ca and P (Ca/P) in the corrosion products also differed. The Ca deficient region and higher content of Al in corrosion product than AZ31 magnesium alloy were identified after in vivo test in contrast with the result of in vitro test. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Double fillet lap of laser welding of thin sheet AZ31B Mg alloy

    Science.gov (United States)

    Ishak, Mahadzir; Salleh, M. N. M.

    2018-05-01

    In this paper, we describe the experimental laser welding of thin sheet AZ31B using double fillet lap joint method. Laser welding is capable of producing high quality weld seams especially for small weld bead on thin sheet product. In this experiment, both edges for upper and lower sheets were subjected to the laser beam from the pulse wave (PW) mode of fiber laser. Welded sample were tested their joint strength by tensile-shear strength method and the fracture loads were studied. Strength for all welded samples were investigated and the effect of laser parameters on the joint strength and appearances were studied. Pulsed energy (EP) from laser process give higher effect on joint strength compared to the welding speed (WS) and angle of irradiation (AOI). Highest joint strength was possessed by sample with high EP with the same value of WS and AOI. The strength was low due to the crack defect at the centre of weld region.

  7. Laser assisted self-pierce riveting of AZ31 magnesium alloy strips

    International Nuclear Information System (INIS)

    Durandet, Y.; Deam, R.; Beer, A.; Song, W.; Blacket, S.

    2010-01-01

    Laser assisted self-piercing riveting (LSPR) is a new solid state process that enables low ductility materials to be mechanically joined without cracking. A simple but effective thermal analysis of LSPR is presented that enabled both the absorption of the laser radiation and heat transfer between plies to be determined. The approach was applied to experimental data for LSPR joining of AZ31B-H24 magnesium alloy sheets. It is shown that by using this analytical approach, the temperature at the onset of joining could be estimated and related to observations of joint quality. It was found that crack-free joints were produced at strip temperatures above 200 o C at the time of rivet insertion.

  8. A two-step superplastic forging forming of semi-continuously cast AZ70 magnesium alloy

    Directory of Open Access Journals (Sweden)

    Pan Wang

    2015-03-01

    Full Text Available A two-step technology combined forging with superplastic forming has been developed to enhance the forgeability of semi-continuously cast AZ70 magnesium alloy and realize the application of the as-cast magnesium alloy in large deformation bullet shell. In the first step, fine-grained microstructure preforms that are suitable for superplastic forming were obtained by reasonably designing the size of the initial blanks with the specific height-to-diameter ratio, upsetting the blanks and subsequent annealing. In the second step, the heat treated preforms were forged into the end products at the superplastic conditions. The end products exhibit high quality surface and satisfied microstructure. Consequently, this forming technology that not only avoids complicating the material preparation but also utilizes higher strain rate superplastic provides a near net-shaped novel method on magnesium forging forming technology using as-cast billet.

  9. Study on hybrid heat source overlap welding of magnesium alloy AZ31B

    International Nuclear Information System (INIS)

    Liang, G.L.; Zhou, G.; Yuan, S.Q.

    2009-01-01

    The magnesium alloy AZ31B was overlap welded by hybrid welding (laser-tungsten inert gas arc). According to the hybrid welding interaction principle, a new heat source model, hybrid welding heat source model, was developed with finite element analysis. At the same time, using a high-temperature metallographical microscope, the macro-appearance and microstructure characteristics of the joint after hybrid overlap welding were studied. The results indicate that the hybrid welding was superior to the single tungsten inert gas welding or laser welding on the aspects of improving the utilized efficiency of the arc and enhancing the absorptivity of materials to laser energy. Due to the energy characteristics of hybrid overlap welding the macro-appearance of the joint was cup-shaped, the top weld showed the hybrid welding microstructure, while, the lower weld showed the typical laser welding microstructure

  10. Study on hybrid heat source overlap welding of magnesium alloy AZ31B

    Energy Technology Data Exchange (ETDEWEB)

    Liang, G.L. [Department of Electromechanical Engineering, Tangshan College, Tangshan 063000 (China)], E-mail: guoliliang@sohu.com; Zhou, G. [School of Material Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Yuan, S.Q. [Department of Electromechanical Engineering, Tangshan College, Tangshan 063000 (China)

    2009-01-15

    The magnesium alloy AZ31B was overlap welded by hybrid welding (laser-tungsten inert gas arc). According to the hybrid welding interaction principle, a new heat source model, hybrid welding heat source model, was developed with finite element analysis. At the same time, using a high-temperature metallographical microscope, the macro-appearance and microstructure characteristics of the joint after hybrid overlap welding were studied. The results indicate that the hybrid welding was superior to the single tungsten inert gas welding or laser welding on the aspects of improving the utilized efficiency of the arc and enhancing the absorptivity of materials to laser energy. Due to the energy characteristics of hybrid overlap welding the macro-appearance of the joint was cup-shaped, the top weld showed the hybrid welding microstructure, while, the lower weld showed the typical laser welding microstructure.

  11. Evaluation of cracking in the 241-AZ tank farm ventilation line at the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    ANANTATMULA, R.P.

    1999-10-20

    In the period from April to October of 1988, a series of welding operations on the outside of the AZ Tank Farm ventilation line piping at the Hanford Site produced unexpected and repeated cracking of the austenitic stainless steel base metal and of a seam weld in the pipe. The ventilation line is fabricated from type 304L stainless steel pipe of 24 inch diameter and 0.25 inch wall thickness. The pipe was wrapped in polyethylene bubble wrap and buried approximately 12 feet below grade. Except for the time period between 1980 and 1987, impressed current cathodic protection has been applied to the pipe since its installation in 1974. The paper describes the history of the cracking of the pipe, the probable cracking mechanisms, and the recommended future action for repair/replacement of the pipe.

  12. Chitosan coatings crosslinked with genipin for corrosion protection of AZ31 magnesium alloy sheets.

    Science.gov (United States)

    de Y Pozzo, Ludmila; da Conceição, Thiago F; Spinelli, Almir; Scharnagl, Nico; Pires, Alfredo T N

    2018-02-01

    In this study, coatings of chitosan crosslinked with genipin were prepared on sheets of AZ31 magnesium alloy and their corrosion protection properties were characterized by means of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The coatings were also characterized by means of FTIR and XPS. It was observed that the crosslinking process decreases the corrosion current and shifts the corrosion potential of the alloy to less negative values. The EIS analysis demonstrated that the crosslinking process increases the maximum impedance after short and long exposure times. The superior performance of the crosslinked coatings is related to a lower degree of swelling, as observed in the swelling tests carried out on free-standing films. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Semiconducting behavior of the anodically passive films formed on AZ31B alloy

    Directory of Open Access Journals (Sweden)

    A. Fattah-alhosseini

    2014-12-01

    Full Text Available This work includes determination of the semiconductor character and estimation of the dopant levels in the passive film formed on AZ31B alloy in 0.01 M NaOH, as well as the estimation of the passive film thickness as a function of the film formation potential. Mott–Schottky analysis revealed that the passive films displayed n-type semiconductive characteristics, where the oxygen vacancies and interstitials preponderated. Based on the Mott–Schottky analysis, it was shown that the calculated donor density increases linearly with increasing the formation potential. Also, the electrochemical impedance spectroscopy (EIS results indicated that the thickness of the passive film was decreased linearly with increasing the formation potential. The results showed that decreasing the formation potential offer better conditions for forming the passive films with higher protection behavior, due to the growth of a much thicker and less defective films.

  14. Microstructural evolution of AZ31 magnesium alloy subjected to sliding friction treatment

    Science.gov (United States)

    Zhang, Wei; Lu, Jinwen; Huo, Wangtu; Zhang, Yusheng; Wei, Q.

    2018-06-01

    Microstructural evolution and grain refinement mechanism in AZ31 magnesium alloy subjected to sliding friction treatment were investigated by means of transmission electron microscopy. The process of grain refinement was found to involve the following stages: (I) coarse grains were divided into fine twin plates through mechanical twinning; then the twin plates were transformed to lamellae with the accumulation of residual dislocations at the twin boundaries; (II) the lamellae were separated into subgrains with increasing grain boundary misorientation and evolution of high angle boundaries into random boundaries by continuous dynamic recrystallisation (cDRX); (III) the formation of nanograins. The mechanisms for the final stage, the formation of nanograins, can be classified into three types: (i) cDRX; (ii) discontinuous dynamic recrystallisation (dDRX); (iii) a combined mechanism of prior shear-band and subsequent dDRX. Stored strain energy plays an important role in determining deformation mechanisms during plastic deformation.

  15. Microstructure of AZ31 Magnesium Alloy deformed by indentation-flattening compound deformation technology

    Science.gov (United States)

    Wang, Minghao; Wang, Zhongtang; Yu, Xiaolin

    2018-03-01

    Characteristic of indentation-flattening compound deformation technology (IFCDT) is discussed, and the parameters of IFCDT are defined. Performance of magnesium alloy AZ31 sheet deformed by IFCDT is researched. The effect of IFCDT coefficient, temperature and reduction ratio on the microstructure of magnesium alloy sheet is analyzed. The research results show that the volume fraction of the twin crystal decreases gradually and the average grain size increases with increasing of coefficient of IFCDT. With increase of the reduction ratio, the volume fraction of the twin crystal gradually increases, and the average grain size also increases. With increase of deformation temperature, the volume fraction of the twin crystal decreases gradually, and the twin crystal grain size increases.

  16. Merging airborne and carborne radiometric data for surveying the Deir Az-Zor area, Syria

    International Nuclear Information System (INIS)

    Jubeli, Y.M.; Aissa, M.; Al-Hent, R.

    1997-01-01

    To complete the radiometric map of Syria, and to estimate the natural background radiation levels for environmental monitoring, a carborne survey was undertaken over the Deir Az-Zor area. This area was not covered by a previous airborne survey, except for peripheral regions in the south and west. To complete the radiometric map, results of the carborne and airborne surveys had to be merged. This paper presents the merging procedure which was used after normalizing the two data sets to match each other. No anomalies suitable for radioelement exploration were found. However, the overall radiometric maps resulting from the present work were consistent with the maps of the areas covered by the airborne survey. (author)

  17. Alelopatía en Saccharum spp. (caña de azúcar

    Directory of Open Access Journals (Sweden)

    R. A. Arévalo

    2011-01-01

    6 Aminoácidos no proteicos, 7 Lactonas no saturadas, 8 ácidos orgánicos, alcoholes alifáticos, aldehídos y cetonas, 9 ácidos grasos, naftoquinonas, antraquinonas, y complejos de quinonas, 10 Coumarina. Los mecanismos de acción en la mayoría de los aleloquímicos son aún desconocidos. Las plantas arvenses, como Cypro-Cyperus rotundus L.; Rooex-Rottboellia exaltata L. f. causan alelopatía en caña de azúcar. Las plantas de Cucsa- Cucumis sativus L. son afectadas por efectos alelopáticos de plantas de Rooex. Las coberturas utilizadas en la agricultura sostenible tienen propiedades alelopáticas. Las respuestas de las plantas cultivadas a los aleloquímicos pueden ser susceptibles, tolerantes o resistentes. La alelopatía tiene gran potencial para el manejo de plagas en la agricultura.

  18. Improving the corrosion properties of magnesium AZ31 alloy GTA weld metal using microarc oxidation process

    Institute of Scientific and Technical Information of China (English)

    M.Siva Prasad; M.Ashfaq; N.Kishore Babu; A.Sreekanth; K.Sivaprasad; V.Muthupandi

    2017-01-01

    In this work,the morphology,phase composition,and corrosion properties of microarc oxidized (MAO) gas tungsten arc (GTA) weldments of AZ31 alloy were investigated.Autogenous gas tungsten arc welds were made as full penetration bead-on-plate welding under the alternating-current mode.A uniform oxide layer was developed on the surface of the specimens with MAO treatment in silicate-based alkaline electrolytes for different oxidation times.The corrosion behavior of the samples was evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy.The oxide film improved the corrosion resistance substantially compared to the uncoated specimens.The sample coated for 10 min exhibited better corrosion properties.The corrosion resistance of the coatings was concluded to strongly depend on the morphology,whereas the phase composition and thickness were concluded to only slightly affect the corrosion resistance.

  19. Process of film formation by anodizing AZ91D magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Qian Jiangang; Li Di; Zhang Feng [School of Materials Science and Engineering, Beijing Univ. of Aeronautics and Astronautics (China)

    2005-07-01

    The kinetics of film-forming process by anodizing AZ91D Mg alloy has been studied by ways of voltage-time and thickness-time curve, and the surface morphology, structure, composition and valence of element, phase constituent of anodic films have been analyzed by SEM, EDS, XPS and XRD respectively. The results show that the film-forming course can be divided into four stages. Formation of dense layer before sparking is the first stage. Formation of porous layer accompanied with a bit of small sparking is the second stage. Porous layer fast growth along with middle sparking is the third stage. Porous layer slowly-growth along with bigger sparking is the fourth stage. The anodic films contains approximately Mg,O,Si and B, which is composed mainly of MgO, MgSiO{sub 3} and Mg{sub 3}B{sub 2}O{sub 6}. (orig.)

  20. Microstructure and mechanical property of dual-directional-extruded Mg alloy AZ31

    International Nuclear Information System (INIS)

    Lu Liwei; Liu Tianmo; Jiang Shan; Pan Fushen; Liu Qing; Wang Zhongchang

    2010-01-01

    We report microstructure evolution and mechanical property of Mg alloy AZ31 processed by a new deformation technique, dual-directional extrusion (DDE). Using optical microscopy, scanning electron microscopy, and electron back scatter diffraction technique, we attribute the significant refinement of original coarse grains in the DDE-processed alloy to the occurrence of dynamic recrystallization. Moreover, we find that low temperature is crucial for yielding fine grain, which consequently results in high micro-hardness and yield stress, large fracture strain, and enhanced elongation. The improved mechanical properties are comparable or even superior to those of the alloy subjected to other deformation techniques, rendering the DDE a promising way for further tailoring properties of Mg-based alloys.

  1. Modelling of peak temperature during friction stir processing of magnesium alloy AZ91

    Science.gov (United States)

    Vaira Vignesh, R.; Padmanaban, R.

    2018-02-01

    Friction stir processing (FSP) is a solid state processing technique with potential to modify the properties of the material through microstructural modification. The study of heat transfer in FSP aids in the identification of defects like flash, inadequate heat input, poor material flow and mixing etc. In this paper, transient temperature distribution during FSP of magnesium alloy AZ91 was simulated using finite element modelling. The numerical model results were validated using the experimental results from the published literature. The model was used to predict the peak temperature obtained during FSP for various process parameter combinations. The simulated peak temperature results were used to develop a statistical model. The effect of process parameters namely tool rotation speed, tool traverse speed and shoulder diameter of the tool on the peak temperature was investigated using the developed statistical model. It was found that peak temperature was directly proportional to tool rotation speed and shoulder diameter and inversely proportional to tool traverse speed.

  2. El legado psicológico de Rogelio Díaz-Guerrero

    OpenAIRE

    Reynaldo Alarcón

    2010-01-01

    O autor identifica quatro dimensões básicas na obra do psicólogo mexicano Rogelio Díaz-Guerrero (1918-2004): a) seu interesse pioneiro por construir uma psicología do mexicano se inicia com a publicação de Estudios de psicología del mexicano (1961) e culmina 42 anos depois com seu livro Bajo las garras de la cultura. Psicología del mexicano 2 (2003); b) a orientação culturalista de seu pensamento; c) sua adesão à psicologia transcultural, em reação ao etnocentrismo psicológico dominante em su...

  3. Effect of equal channel angular pressing on the strength and ductility of an AZ80 alloy

    International Nuclear Information System (INIS)

    Pereira, T S; Chung, C W; Ding, R; Chiu, Y L

    2009-01-01

    Equal channel angular pressing (ECAP) was applied to an extruded AZ80 Mg alloy in order to refine microstructure and enhance mechanical properties. The results show that the initial grain size of 20 μm of the as-extruded samples has been reduced by 75% after the first pass of ECAP, down to about 5 μm. Also as a result of the severe plastic deformation, the intermetallic compound Mg 17 Al 12 , which was distributed along grain boundaries and forms networks before the ECAP, has been re-arranged into a more homogeneous distribution and with a more spherical shape after the ECAP. Although no strengthening effect has been observed, the grain refinement and precipitate fragmentation caused by the ECAP has resulted in a 28% increase in the elongation to failure in tensile tests. Fractography observation and texture measurement have also been carried out.

  4. Grain boundary sliding mechanism during high temperature deformation of AZ31 Magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Roodposhti, Peiman Shahbeigi, E-mail: pshahbe@ncsu.edu [North Carolina State University (United States); University of Connecticut (United States); Sarkar, Apu; Murty, Korukonda Linga [North Carolina State University (United States); Brody, Harold [University of Connecticut (United States); Scattergood, Ronald [North Carolina State University (United States)

    2016-07-04

    High temperature tensile creep tests were conducted on AZ31 Magnesium alloy at low stress range of 1–13 MPa to clarify the existence of grain boundary sliding (GBS) mechanism during creep deformation. Experimental data within the GBS regime shows the stress exponent is ~2 and the activation energy value is close to that for grain boundary diffusion. Analyses of the fracture surface of the sample revealed that the GBS provides many stress concentrated sites for diffusional cavities formation and leads to premature failure. Scanning electron microscopy images show the appearances of both ductile and brittle type fracture mechanism. X-ray diffraction line profile analysis (based on Williamson-Hall technique) shows a reduction in dislocation density due to dynamic recovery (DRV). A correlation between experimental data and Langdon's model for GBS was also demonstrated.

  5. Initial deposition mechanism of electroless nickel plating on AZ91D magnesium alloys

    International Nuclear Information System (INIS)

    Song, Y.; Shan, D.; Han, E.

    2006-01-01

    The pretreatment processes and initial deposition mechanism of electroless nickel plating on AZ91D magnesium alloy were investigated by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX). The results showed that alkaline cleaning could remove the greases and oils from the substrate surface. Acid etching could wipe off the metal chippings and oxides. The hydrofluoric acid activating process which could improve the adhesion of coating to substrate played a key role in the subsequent process of electroless nickel plating. The nickel coating was deposited preferentially on the primary α phase and then spread to the eutectic α phase and β phase. The nickel initially nucleated on the primary α phase by a replacement reaction, then grew depending on the autocatalysis function of nickel. The coating on the β phase displayed better adhesion than that on the α phase due to the nails fixing effect. (author)

  6. Twinning behaviors of a rolled AZ31 magnesium alloy under multidirectional loading

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Dewen [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Liu, Tianmo, E-mail: tmliu@cqu.edu.cn [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Luo, Longjing [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Lu, Liwei [College of Mechanical and Electrical Engineering, Hunan University of Science and Technology, Xiangtan 411201, Hunan (China); Chen, Huicong; Shi, Dongfeng [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China)

    2017-02-15

    The microstructure and texture evolution of an AZ31 magnesium rolled sheet during quasi-static compression at strain rates of 10{sup −3} s{sup −1} has been investigated by in situ electron backscattered diffraction. The influence of the initial and pre-deformed texture on the predominant deformation mechanisms during compression has been examined. It has been found that extensive grain reorientation due to (10 − 12) tensile twinning appeared when compressed along transverse direction. Tensile twin variants were observed under this loading condition, and different variants will cause an effect to the following deformation. Several twinning modes occurred with continuative loading along rolling direction. - Highlights: •Twinning behaviors were investigated through in situ multidirectional compressive tests. •Deformation behavior was affected by the twin variants. •Four types of twinning behaviors were observed during deformation process.

  7. CO2 and diode laser welding of AZ31 magnesium alloy

    International Nuclear Information System (INIS)

    Zhu Jinhong; Li Lin; Liu Zhu

    2005-01-01

    Magnesium alloys are being increasingly used in automotive and aerospace structures. Laser welding is an important joining method in such applications. There are several kinds of industrial lasers available at present, including the conventional CO 2 and Nd:YAG lasers as well as recently available high power diode lasers. A 1.5 kW diode laser and a 2 kW CO 2 laser are used in the present study for the welding of AZ31 alloys. It is found that different welding modes exist, i.e., keyhole welding with the CO 2 laser and conduction welding with both the CO 2 and the diode lasers. This paper characterizes welds in both welding modes. The effect of beam spot size on the weld quality is analyzed. The laser processing parameters are optimized to obtain welds with minimum defects

  8. Data acquisition and PV module power production in upgraded TEP/AzRISE solar test yard

    Science.gov (United States)

    Bennett, Whit E.; Fishgold, Asher D.; Lai, Teh; Potter, Barrett G.; Simmons-Potter, Kelly

    2017-08-01

    The Tucson Electric Power (TEP)/University of Arizona AzRISE (Arizona Research Institute for Solar Energy) solar test yard is continuing efforts to improve standardization and data acquisition reliability throughout the facility. Data reliability is ensured through temperature-insensitive data acquisition devices with battery backups in the upgraded test yard. Software improvements allow for real-time analysis of collected data, while uploading to a web server. Sample data illustrates high fidelity monitoring of the burn-in period of a polycrystalline silicon photovoltaic module test string with no data failures over 365 days of data collection. In addition to improved DAQ systems, precision temperature monitoring has been implemented so that PV module backside temperatures are routinely obtained. Weather station data acquired at the test yard provides local ambient temperature, humidity, wind speed, and irradiance measurements that have been utilized to enable characterization of PV module performance over an extended test period

  9. Grain refinement of AZ31 by (SiC)P: Theoretical calculation and experiment

    International Nuclear Information System (INIS)

    Guenther, R.; Hartig, Ch.; Bormann, R.

    2006-01-01

    Grain refinement of gravity die-cast Mg-alloys can be achieved via two methods: in situ refinement by primary precipitated metallic or intermetallic phases, and inoculation of the melt via ceramic particles that remain stable in the melt due to their high thermodynamic stability. In order to clarify grain refinement mechanisms and optimize possible potent refiners in Mg-alloys, a simulation method for heterogeneous nucleation based on a free growth model has been developed. It allows the prediction of the grain size as a function of the particle size distribution, the volumetric content of ceramic inoculants, the cooling rate and the alloy constitution. The model assumptions were examined experimentally by a study of the grain refinement of (SiC) P in AZ31. Additions of (SiC) P result in significant grain refinement, if appropriate parameters for ceramic particles are chosen. The model makes quantitatively correct predictions for the grain size and its variation with cooling rate

  10. Corrosion of magnesium alloy AZ31 screws is dependent on the implantation site

    Energy Technology Data Exchange (ETDEWEB)

    Willbold, E. [Laboratory for Biomechanics and Biomaterials, Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Strasse 1-7, D - 30625 Hannover (Germany); Kaya, A.A. [Mugla University, Engineering Faculty, Metallurgy and Materials Engineering Department, Mugla (Turkey); Kaya, R.A. [MedicalPark Hospital, Kueltuer Sok No:1, 34160 Bahcelievler, Istanbul (Turkey); Beckmann, F. [Helmholtz-Zentrum Geesthacht, Institute of Materials Research, Max-Planck-Str.1, D - 21502 Geesthacht (Germany); Witte, F., E-mail: witte.frank@mh-hannover.de [Laboratory for Biomechanics and Biomaterials, Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Strasse 1-7, D - 30625 Hannover (Germany)

    2011-12-15

    The corrosion of biodegradable materials is a crucial issue in implant development. Among other materials, magnesium and magnesium based alloys are one of the most promising candidates. Since the corrosion of biodegradable materials depends on different physiological parameters like pH or ion concentrations, the corrosion might be different in different biological environments. To investigate this issue, we produced screws from magnesium alloy AZ31 and implanted them into the hip bone of 14 sheep. After 3 and 6 months, the screws were explanted and analyzed with synchrotron-radiation based micro-computed tomography and hard tissue histology. We found considerable differences in the corrosion behavior of the magnesium screws with respect to its original tissue location. However, we could detect a normal immunological tissue response.

  11. Formation mechanisms of periodic longitudinal microstructure and texture patterns in friction stir welded magnesium AZ80

    Energy Technology Data Exchange (ETDEWEB)

    Hiscocks, J., E-mail: j.hiscocks@queensu.ca [Department of Mechanical and Materials Engineering, Queen' s University, Kingston, Ontario (Canada); Diak, B.J. [Department of Mechanical and Materials Engineering, Queen' s University, Kingston, Ontario (Canada); Gerlich, A.P. [Department of Mechanical and Mechatronics Engineering, Waterloo University, Waterloo, Ontario (Canada); Daymond, M.R. [Department of Mechanical and Materials Engineering, Queen' s University, Kingston, Ontario (Canada)

    2016-12-15

    Many studies of friction stir welding have shown that periodicity of metal flow around the tool pin may result in the formation of periodic differences in microstructure and texture in the weld nugget area correlated with the weld pitch. The current work investigates the periodicity of magnesium weld microtexture in the nugget region and its association with material flow using optical and electron microscopy. Two welds created in AZ80 at different processing conditions are presented in detail, one illustrating periodic longitudinal texture change, and one showing for the first time that periodic variations in texture, grain size, or composition are not defining features of periodic nugget flow. While nugget texture is dominated by shear deformation, it was found here to be affected to a lesser degree by compaction of material behind the welding tool, which led to reduction in intensity of the shear texture fiber. The decreased tendency for magnesium based alloys to form periodic patterns as compared to aluminum based alloys is explained with reference to the shear textures. - Highlights: •It is shown here that periodic material flow in the nugget does not necessitate longitudinal texture patterns. •Longitudinal texture patterns are shown to be present or absent in Mg AZ80 based on processing conditions. •Texture in the nugget is mainly dictated by shear deformation, but has measurable effects from other deformation modes. •Explanation of why longitudinal texture change is frequently reported in aluminum but not magnesium alloys is provided. •A new vector visualization of material flow based on EBSD data analysis is shown.

  12. Effect of surface nanocrystallization on the microstructural and corrosion characteristics of AZ91D magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Laleh, M., E-mail: laleh.m.1992@gmail.com [Department of Materials Engineering, Faculty of Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of); Kargar, Farzad, E-mail: farzad.kargar@gmail.com [Department of Materials Engineering, Faculty of Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of)

    2011-09-15

    Highlights: > Nanostructured surface layers were produced on AZ91D magnesium alloy by using SMAT. > Thickness of the deformed layer increased with increasing of the balls size. > Top surface microhardness for all of the SMATed samples increased significantly. > SMAT increased the surface roughness; increase in balls diameter increased the roughness. > SMAT using 2 mm balls increased the corrosion resistance significantly. - Abstract: Surface distinct deformed layers with thicknesses up to 150 {mu}m, with grain size in the top most surface is in the nanometer scale, were produced on AZ91D magnesium alloy using surface mechanical attrition treatment (SMAT). Effects of different ball size on the properties of the SMATed samples were investigated. The microstructural, grain size, hardness and roughness features of the treated surfaces were characterized using optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), micro-indenter and digital roughness meter, respectively. Corrosion behavior of the samples was evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. It is found that the ball diameter does not have a significant effect on the top surface grain size, but the thickness of the deformed layer increases with increase of ball size, from 50 {mu}m for 2 mm balls to 150 {mu}m for 5 mm balls. For all of the SMATed samples, the top surface microhardness value increased significantly and did not show any obvious change for samples treated with different balls. Corrosion studies show that the corrosion resistance of the sample treated with 2 mm balls is higher than that of those treated with 3 mm and 5 mm balls. This can be mainly attributed to the surface roughness and defects density of the samples, which are higher for the SMATed samples with 3 mm and 5 mm balls compared with that of sample SMATed with 2 mm balls.

  13. Non-sparking anodization process of AZ91D magnesium alloy under low AC voltage

    International Nuclear Information System (INIS)

    Li, Weiping; Li, Wen; Zhu, Liqun; Liu, Huicong; Wang, Xiaofang

    2013-01-01

    Highlights: ► Four different processes appear on magnesium alloys with applied voltage increase. ► Non-sparking film formation process occurred in the range of 6–10 V AC. ► The film was composed of Mg 2 SiO 4 with a stable growth rate in 30 min. ► Film growth was a balance of electrochemical dissolution and chemical deposition. -- Abstract: Anodization is widely recognized as one of the most important surface treatments for magnesium alloys. However, since high voltage oxidation films are limited in some applications due to porosity and brittleness, it is worthwhile to explore the non-sparking oxidizing process. In this work, AZ91D was electrochemically anodized at different AC voltages in an electrolyte containing 120 g/L NaOH and 80 g/L Na 2 SiO 3 ·9H 2 O. The effects of voltage on the surface morphology, composition and reaction process, especially the non-sparking discharge anodic film formation process, were investigated. The results showed that four different processes would appear according to the applied voltage variation from 6 V to 40 V, and that the non-sparking film formation process occurred in the range of 6–10 V. The film formed on the AZ91D surface under 10 V AC was mainly composed of Mg 2 SiO 4 with a lamellar structure. The horizontal and vertical expansion of the lamellar structure resulted in the formation of a multi-layered structure with a stable, linear growth rate for 30 min. The non-sparking film formation process can be considered to be the result of a balance of electrochemical dissolution and chemical deposition reaction

  14. Non-sparking anodization process of AZ91D magnesium alloy under low AC voltage

    Energy Technology Data Exchange (ETDEWEB)

    Li, Weiping, E-mail: liweiping@buaa.edu.cn [Key Laboratory of Aerospace Materials and Performance (Ministry of Education), School of Materials Science and Engineering, Beihang University, Beijing 100191 (China); Li, Wen [AVIC Beijing Aeronautical Manufacturing Technology Research Institue, Beijing 100024 (China); Zhu, Liqun; Liu, Huicong; Wang, Xiaofang [Key Laboratory of Aerospace Materials and Performance (Ministry of Education), School of Materials Science and Engineering, Beihang University, Beijing 100191 (China)

    2013-04-20

    Highlights: ► Four different processes appear on magnesium alloys with applied voltage increase. ► Non-sparking film formation process occurred in the range of 6–10 V AC. ► The film was composed of Mg{sub 2}SiO{sub 4} with a stable growth rate in 30 min. ► Film growth was a balance of electrochemical dissolution and chemical deposition. -- Abstract: Anodization is widely recognized as one of the most important surface treatments for magnesium alloys. However, since high voltage oxidation films are limited in some applications due to porosity and brittleness, it is worthwhile to explore the non-sparking oxidizing process. In this work, AZ91D was electrochemically anodized at different AC voltages in an electrolyte containing 120 g/L NaOH and 80 g/L Na{sub 2}SiO{sub 3}·9H{sub 2}O. The effects of voltage on the surface morphology, composition and reaction process, especially the non-sparking discharge anodic film formation process, were investigated. The results showed that four different processes would appear according to the applied voltage variation from 6 V to 40 V, and that the non-sparking film formation process occurred in the range of 6–10 V. The film formed on the AZ91D surface under 10 V AC was mainly composed of Mg{sub 2}SiO{sub 4} with a lamellar structure. The horizontal and vertical expansion of the lamellar structure resulted in the formation of a multi-layered structure with a stable, linear growth rate for 30 min. The non-sparking film formation process can be considered to be the result of a balance of electrochemical dissolution and chemical deposition reaction.

  15. Archaeological studies at Drill Hole U20az Pahute Mesa, Nye county, Nevada. [Contains bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, A.H.; Hemphill, M.L.; Henton, G.H.; Lockett, C.L.; Nials, F.L.; Pippin, L.C.; Walsh, L.

    1991-07-01

    During the summer of 1987, the Quaternary Sciences Center (formerly Social Science Center) of the Desert Research Institute (DRI), University of Nevada System, conducted data recovery investigations at five archaeological sites located near Drill Hole U20az on the Nevada Test Site in southern Nevada. These sites were among 12 recorded earlier during an archaeological survey of the drill hole conducted as part of the environmental compliance activities of the Department of Energy (DOE). The five sites discussed in this report were considered eligible for the National Register of Historic Places and were in danger of being adversely impacted by construction activities or by effects of the proposed underground nuclear test. Avoidance of these sites was not a feasible alternative; thus DRI undertook a data recovery program to mitigate expected adverse impacts. DRI's research plan included controlled surface collections and excavation of the five sites in question, and had the concurrence of the Nevada Division of Historic Preservation and Archaeology and the Advisory Council of Historic Preservation. Of the five sites investigated, the largest and most complex, 26Ny5207, consists of at least three discrete artifact concentrations. Sites 26Ny5211 and 26Ny5215, both yielded considerable assemblages. Site 26Ny5206 is very small and probably is linked to 26Ny5207. Site 26Ny5205 contained a limited artifact assemblage. All of the sites were open-air occurrences, and, with one exception contained no or limited subsurface cultural deposits. Only two radiocarbon dates were obtained, both from 26Ny5207 and both relatively recent. While the investigations reported in the volume mitigate most of the adverse impacts from DOE activities at Drill Hole U20az, significant archaeological sites may still exist in the general vicinity. Should the DOE conduct further activities in the region, additional cultural resource investigations may be required. 132 refs., 71 figs., 44 tabs.

  16. Effect of surface nanocrystallization on the microstructural and corrosion characteristics of AZ91D magnesium alloy

    International Nuclear Information System (INIS)

    Laleh, M.; Kargar, Farzad

    2011-01-01

    Highlights: → Nanostructured surface layers were produced on AZ91D magnesium alloy by using SMAT. → Thickness of the deformed layer increased with increasing of the balls size. → Top surface microhardness for all of the SMATed samples increased significantly. → SMAT increased the surface roughness; increase in balls diameter increased the roughness. → SMAT using 2 mm balls increased the corrosion resistance significantly. - Abstract: Surface distinct deformed layers with thicknesses up to 150 μm, with grain size in the top most surface is in the nanometer scale, were produced on AZ91D magnesium alloy using surface mechanical attrition treatment (SMAT). Effects of different ball size on the properties of the SMATed samples were investigated. The microstructural, grain size, hardness and roughness features of the treated surfaces were characterized using optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), micro-indenter and digital roughness meter, respectively. Corrosion behavior of the samples was evaluated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. It is found that the ball diameter does not have a significant effect on the top surface grain size, but the thickness of the deformed layer increases with increase of ball size, from 50 μm for 2 mm balls to 150 μm for 5 mm balls. For all of the SMATed samples, the top surface microhardness value increased significantly and did not show any obvious change for samples treated with different balls. Corrosion studies show that the corrosion resistance of the sample treated with 2 mm balls is higher than that of those treated with 3 mm and 5 mm balls. This can be mainly attributed to the surface roughness and defects density of the samples, which are higher for the SMATed samples with 3 mm and 5 mm balls compared with that of sample SMATed with 2 mm balls.

  17. Software configuration management plan, 241-AY and 241-AZ tank farm MICON automation system

    International Nuclear Information System (INIS)

    Hill, L.F.

    1997-01-01

    This document establishes a Computer Software Configuration Management Plan (CSCM) for controlling software for the MICON Distributed Control System (DCS) located at the 241-AY and 241-AZ Aging Waste Tank Farm facilities in the 200 East Area. The MICON DCS software controls and monitors the instrumentation and equipment associated with plant systems and processes. A CSCM identifies and defines the configuration items in a system (section 3.1), controls the release and change of these items throughout the system life cycle (section 3.2), records and reports the status of configuration items and change requests (section 3.3), and verifies the completeness and correctness of the items (section 3.4). All software development before initial release, or before software is baselined, is considered developmental. This plan does not apply to developmental software. This plan applies to software that has been baselined and released. The MICON software will monitor and control the related instrumentation and equipment of the 241-AY and 241-AZ Tank Farm ventilation systems. Eventually, this software may also assume the monitoring and control of the tank sludge washing equipment and other systems as they are brought on line. This plan applies to the System Cognizant Manager and MICON Cognizant Engineer (who is also referred to herein as the system administrator) responsible for the software/hardware and administration of the MICON system. This document also applies to any other organizations within Tank Farms which are currently active on the system including system cognizant engineers, nuclear operators, technicians, and control room supervisors

  18. The libertarian educational proposals of José Cabrera Díaz Las propuestas educativas libertarias de José Cabrera Díaz

    Directory of Open Access Journals (Sweden)

    Manuel FERRAZ LORENZO

    2013-09-01

    Full Text Available The purpose of this article is to explain the operational guidelines of the Canarian workers movement in the early Twentieth Century in connection with integral educational proposals. For this purpose, we have taken advantage of the articles published in the press by on of the leading exponents of the movement, a member of the anarchist school of thought, José Cabrera Diaz, whose curriculum vitae indicates his importance. He was a journalist, trades union leader and an outand- out defender of rationalist education and of the creation of people's schools, the purpose of which was to eradicate —by combating illiteracy and ignorance— the abusive quasi-feudal practices of the «caciques» that existed in the Canarian Archipiélago.El objetivo de este artículo consiste en exponer las líneas de trabajo del movimiento obrero en Canarias a comienzos de siglo, en lo concerniente a sus propuestas educativas de tipo integral. Para ello nos hemos servido de los trabajos publicados en prensa de uno de sus máximos representantes, inserto en la corriente de pensamiento anarquista: José Cabrera Díaz, cuyo curriculum lo dice todo. Periodista, líder sindical y, además, defensor a ultranza de la educación racionalista y de la creación de escuelas populares, destinadas a erradicar —desde la alfabetización y cultura— las prácticas caciquiles existentes en el Archipiélago.

  19. KONTRIBUSI PENGALAMAN PRAKERIN, WAWASAN DUNIA KERJA DAN KOMPETENSI KEJURUAN MELALUI EMPLOYABILITY SKILL SERTA DAMPAKNYA TERHADAP KESIAPAN KERJA LULUSAN SMK KOMPETENSI KEAHLIAN TEKNIK KOMPUTER DAN JARINGAN DI PROBOLINGGO

    Directory of Open Access Journals (Sweden)

    Ega Putriatama

    2016-08-01

    Full Text Available This study aimed to explain the relationship between independent variables, intervening variable and dependent variable, namely prakerin experience (X_1, insight to work world (X_2, honesty competence (X_3, employability skill (X_4, and work readiness (Y with the subject of students SMK in Probolinggo. This study is included in quantitative research. Analysis technique used was path analysis with trimming mode. Population of this research were all students SMK in the City and District of Probolinggo grade XII TKJ academic year 2015-2016. Based on the results of the study, it can be concluded that: (1 prakerin experience, insight to world of work, honesty competence, employability skill and work readiness of students SMK in the City and District of Probolinggo is included into good category  (2 There is a significant influence and positive between prakerin experience, work world insight and honesty competence towards employability skill; (3 There is a significant influence between prakerin experience, work world insight and honest competence towards work readiness through employability skill. Penelitian ini bertujuan untuk menjelaskan hubungan antara variabel bebas, variabel intervening dan variabel terikat, yaitu pengalaman prakerin (X_1, wawasan dunia kerja (X_2, kompetensi kejuruan (X_3, employability skill (X_4, dan kesiapan kerja (Y dengan subjek siswa SMK di Probolinggo. Penelitian ini termasuk dalam jenis penelitian kuantitatif. Teknik analisis yang digunakan dalam penelitian ini adalah analisis jalur (path analysis dengan model trimming. Populasi dalam penelitian ini adalah seluruh siswa SMK Kota dan Kabupaten Probolinggo kelas XII TKJ tahun ajaran 2015/2016. Berdasarkan hasil penelitian  dapat ditarik kesimpulan bahwa: (1 pengalaman prakerin, wawasan dunia kerja, kompetensi kejuruan, employability skill dan kesiapan kerja siswa SMK di kota dan kabupaten probolinggo berada dalam katergori baik (2 terdapat Pengaruh yang signifikan dan

  20. Microstructural evolution and tensile mechanical properties of thixoformed AZ91D magnesium alloy with the addition of yttrium

    International Nuclear Information System (INIS)

    Zhao Zude; Chen Qiang; Kang Feng; Shu Dayu

    2009-01-01

    The microstructure evolution of AZ91D magnesium alloy in the semi-solid state has been proposed or reported in previous literature. However, no detailed investigation has been conducted regarding the relationship between the microstructure and tensile mechanical properties of the thixoformed AZ91D magnesium alloy. In this paper, the microstructure of AZ91D alloy with the addition of yttrium was produced by the semi-solid thermal transformation (SSTT) route and the strain-induced melt activation (SIMA) route, respectively. Isothermal holding experiments investigated grain coarsening and the degree of spheroidization as a function of holding time in the semi-solid state. The SSTT route and the SIMA route were used to obtain the semi-solid feedstock for thixoforming. The results show that solid particles of the SSTT alloy are spheroidized to some extent but the previous irregular shape is still obvious in some of them. While the SIMA alloy exhibits ideal, fine microstructure, in which completely spheroidized solid particles contain little entrapped liquid. The microstructure of the SSTT alloy is less spheroidized compared with the SIMA alloy under the similar isothermal holding condition. As the holding time increases, the mean solid particle size of the SSTT alloy decreases initially, then increases, while the mean solid particle size of the SIMA alloy increases monotonously at 560 deg. C. Compared with the SSTT alloy, the SIMA alloy obtains finer grains under the similar isothermal holding condition. The mechanical properties of the thixoformed AZ91D alloy with the addition of yttrium produced by the SIMA route are better than those of the thixoformed alloy produced by the SSTT route. The ultimate tensile strength, yield strength and elongation for the thixoformed alloy produced by the SIMA route are 303.1 MPa, 147.6 MPa and 13.27%, respectively. The tensile properties for the AZ91D alloy with the addition of yttrium thixoformed from starting material produced by

  1. Cytotoxicity studies of AZ31D alloy and the effects of carbon dioxide on its biodegradation behavior in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jiali, E-mail: wangjialicsu@yahoo.cn [Center for Translational Medicine Research and Development, Institute of Biomedical and Health Engineering, Chinese Academy of Sciences, Shenzhen 518055 (China); Musculoskeletal Research Laboratory, Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong SAR (China); Qin, Ling [Center for Translational Medicine Research and Development, Institute of Biomedical and Health Engineering, Chinese Academy of Sciences, Shenzhen 518055 (China); Musculoskeletal Research Laboratory, Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Hong Kong SAR (China); Wang, Kai [School of Humanities and Social Sciences, Hunan University of Chinese Medicine, Changsha 410208 (China); Wang, Jue; Yue, Ye [Center for Translational Medicine Research and Development, Institute of Biomedical and Health Engineering, Chinese Academy of Sciences, Shenzhen 518055 (China); Li, Yangde [Guangdong Innovation Team for Biodegradable Magnesium and Medical Implants, E-ande, Dongguan 523660 (China); Tang, Jian [Center for Translational Medicine Research and Development, Institute of Biomedical and Health Engineering, Chinese Academy of Sciences, Shenzhen 518055 (China); Li, Weirong [Guangdong Innovation Team for Biodegradable Magnesium and Medical Implants, E-ande, Dongguan 523660 (China)

    2013-10-01

    Magnesium alloys have been advocated as potential artificial bone materials due to their biocompatibility and biodegradability. The understanding of their corrosive mechanism in physiological environments is therefore essential for making application-orientated designs. Thus, this in vitro study was designed to assess the effects of CO{sub 2} on corrosive behavior of AZ31D to mimic in vivo special ingredient. Electrochemical technologies accompanied with Scanning electron microscope, Fourier transform infrared, X-ray diffraction, Energy dispersive spectroscopy and hydrogen evolution measurement were employed to analyze corrosive rates and mechanisms of AZ31D. Moreover, the biocompatibility of AZ31D was assessed with a direct cell attachment assay and an indirect cytotoxicity test in different diluted extracts. The ion concentrations in extracts were measured using inductively coupled plasma mass spectrometry to offer explanations on the differences of cell viability in the indirect test. The results of the direct cytotoxicity assay showed that the corrosive rate of AZ31D was too rapid to allow for cell adhesion. Extracts diluted less than 20 times would cause adverse effects on cell proliferation, likely due to excessive ions and gas release. Moreover, the presence of CO{sub 2} did not cause significant differences on corrosive behavior of AZ31D according to the results of electrochemical testing and hydrogen evolution measurement. This might be caused by the simultaneous process of precipitation and dissolution of MgCO{sub 3} due to the penetration role of CO{sub 2}. This analysis of corrosive atmospheres on the degradation behavior of magnesium alloys would contribute to the design of more scientific in vitro testing systems in the future. - Highlights: • We evaluate the effects of CO{sub 2} on corrosion behavior of magnesium alloys. • We assess the feasibility of commercial AZ31D alloy as potential implants. • CO{sub 2} is not the key factor to minimize

  2. Evaluation of waste temperatures in AWF tanks for bypass mode operation of the 702-AZ ventilation system (Project W-030)

    International Nuclear Information System (INIS)

    Sathyanarayana, K.

    1997-01-01

    This report describes the results of thermal hydraulic analysis performed to provide data in support of Project W-030 to startup new 702-AZ Primary Ventilation System. During the startup of W-030 system, the ventilation system will be operating in bypass mode. In bypass made of operation, the system is capable of supplying 1000 cfm total flow for all four AWF doubleshell tanks. The design of the W-030 system is based on the assumption that both the recirculation loop of the primary ventilation system and the secondary ventilation which provides cooling would be operating. However, during the startup neither the recirculation system nor the secondary ventilation system will be operating. A minimum flow of 100 cfm is required to prevent any flammable gas associated risk. The remaining 600 cfm flow can be divided among the four tanks as necessary to keep the peak sludge temperatures below the operating temperature limit. For the purpose of determining the minimum flow required for cooling each tank, the thermal hydraulic analysis is performed to predict the peak sludge temperatures in AY/AZ tanks under different ventilation flows. The heat load for AZ farm tanks is taken from characterization reports and for the AY farm tanks, the heat load was estimated by thermal analysis using the measured waste temperatures and the waste liquid evaporation rates. The tank 241-AZ-101 and the tank 241-AZ-102 have heat loads of 241,600 and 199,500 Btu/hr respectively. The tank 241-AY-101 and tank 241-AY-102 have heat loads of 41,000 and 33,000 Btu/hr respectively. Using the ambient meteorological conditions of temperature and relative humidity for the air and tank, some soil surface and the sludge levels reported in recent documents, the peak sludge and supernatant temperatures were predicted for various primary ventilation flows ranging from 100 to 400 cfm for AZ tanks and 100 and 150 cfm for AY tanks. The results of these thermal hydraulic analyses are presented. Based on the

  3. S-32: U-14 Yaş Erkek Futbolcuların Teknik-Taktik Değerlendirmesi ve Atletik Performanslarında Relatif Yaşın Etkisi

    Directory of Open Access Journals (Sweden)

    Raziye Dut

    2017-03-01

    Full Text Available GİRİŞ: Aynı kronolojik yaşta doğum tarihi erken olanların sporda yetenek seçimlerinde avantajlı oldukları bilinmektedir Ancak spora özgü motivasyonda, fonksiyonel kapasitede relatif yaş etkisinin olmadığını gösteren çalışmalar da vardır. AMAÇ: Aynı kronolojik yaştaki erkek futbolcularda teknik/taktik ve atletik performans değerlendirmelerinde relatif yaş etkisini incelemektir. GEREÇ-YÖNTEM: U-14 milli takım seçilme kampına davet edilen 286 erkek futbolcunun, teknik; topa yatkınlık, yaratıcılık, hava hakimiyeti, orta kalitesi, rakip eksiltme ve şut kalitesi, taktik ise pozisyon bilgisi, erken karar, doğru karar, sezgi-erken uyarı, oyunun iki yönü atak ve savunma alt boyutları (1-10 puanlandırıldı. Dikey sıçrama, 10m-20m-30m hız, YOYO IRT1, dayanıklılık, çabukluk-çeviklik, çıkış hızı, maksimal hız gibi atletik performans puanları ile karşılaştırıldı. Veriler ortanca ve Inter Quartile Rate (IQR ile özetlendi. Gruplar arası farklılıklarda Mann-Whitney, ANOVA, post hoc Tukey testleri kullanıldı. P0,05 idi. SONUÇ: Seçilmiş U-14 yaş kategorisinde teknik-taktik ve atletik performans değerlendirmelerinde relatif yaş etkisi bulamadık. Futbol gibi yüksek performanslı bir takım sporunda yetenek, performans kadar teknik ve taktik de erken dönemde geliştirilmeli, yönlendirilmelidir.

  4. Systematic understanding of corrosion behavior of plasma electrolytic oxidation treated AZ31 magnesium alloy using a mouse model of subcutaneous implant

    International Nuclear Information System (INIS)

    Jang, Yongseok; Tan, Zongqing; Jurey, Chris; Collins, Boyce; Badve, Aditya; Dong, Zhongyun; Park, Chanhee; Kim, Cheol Sang; Sankar, Jagannathan; Yun, Yeoheung

    2014-01-01

    This study was conducted to identify the differences between corrosion rates, corrosion types, and corrosion products in different physiological environments for AZ31 magnesium alloy and plasma electrolytic oxidation (PEO) treated AZ31 magnesium alloy. In vitro and in vivo tests were performed in Hank's Balanced Salt Solution (HBSS) and mice for 12 weeks, respectively. The corrosion rates of both AZ31 magnesium alloy and PEO treated AZ31 magnesium alloy were calculated based on DC polarization curves, volume of hydrogen evolution, and the thickness of corrosion products formed on the surface. Micro X-ray computed tomography (Micro-CT), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) were used to analyze morphological and chemical characterizations of corrosion products. The results show that there is more severe localized corrosion after in vitro test in HBSS; however, the thicknesses of corrosion products formed on the surface for AZ31 magnesium alloy and PEO treated AZ31 magnesium alloy in vivo were about 40% thicker than the thickness of corrosion products generated in vitro. The ratio of Ca and P (Ca/P) in the corrosion products also differed. The Ca deficient region and higher content of Al in corrosion product than AZ31 magnesium alloy were identified after in vivo test in contrast with the result of in vitro test. - Highlights: • Effects of plasma electrolytic oxidation on AZ31 in vitro and in vivo • Retardation of degradation via plasma electrolytic oxidation in vitro and in vivo • Differentiation of in vitro and in vivo corrosion types and products

  5. Systematic understanding of corrosion behavior of plasma electrolytic oxidation treated AZ31 magnesium alloy using a mouse model of subcutaneous implant

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Yongseok [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC, 27411 (United States); Tan, Zongqing [Internal Medicine, College of Medicine, University of Cincinnati, OH 45211 (United States); Jurey, Chris [Luke Engineering, Wadsworth, OH 44282 (United States); Collins, Boyce [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC, 27411 (United States); Badve, Aditya [Business and Biology, The University of North Carolina at Chapel Hill, NC 27514 (United States); Dong, Zhongyun [Internal Medicine, College of Medicine, University of Cincinnati, OH 45211 (United States); Park, Chanhee; Kim, Cheol Sang [Department of Bio-nano System Engineering, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Sankar, Jagannathan [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC, 27411 (United States); Yun, Yeoheung, E-mail: yyun@ncat.edu [Engineering Research Center for Revolutionizing Metallic Biomaterials (ERC-RMB), North Carolina A and T State University, Greensboro, NC, 27411 (United States)

    2014-12-01

    This study was conducted to identify the differences between corrosion rates, corrosion types, and corrosion products in different physiological environments for AZ31 magnesium alloy and plasma electrolytic oxidation (PEO) treated AZ31 magnesium alloy. In vitro and in vivo tests were performed in Hank's Balanced Salt Solution (HBSS) and mice for 12 weeks, respectively. The corrosion rates of both AZ31 magnesium alloy and PEO treated AZ31 magnesium alloy were calculated based on DC polarization curves, volume of hydrogen evolution, and the thickness of corrosion products formed on the surface. Micro X-ray computed tomography (Micro-CT), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD) were used to analyze morphological and chemical characterizations of corrosion products. The results show that there is more severe localized corrosion after in vitro test in HBSS; however, the thicknesses of corrosion products formed on the surface for AZ31 magnesium alloy and PEO treated AZ31 magnesium alloy in vivo were about 40% thicker than the thickness of corrosion products generated in vitro. The ratio of Ca and P (Ca/P) in the corrosion products also differed. The Ca deficient region and higher content of Al in corrosion product than AZ31 magnesium alloy were identified after in vivo test in contrast with the result of in vitro test. - Highlights: • Effects of plasma electrolytic oxidation on AZ31 in vitro and in vivo • Retardation of degradation via plasma electrolytic oxidation in vitro and in vivo • Differentiation of in vitro and in vivo corrosion types and products.

  6. Lysobacter capsici AZ78 produces cyclo(L-Pro-L-Tyr), a 2,5-diketopiperazine with toxic activity against sporangia of Phytophthora infestans and Plasmopara viticola.

    Science.gov (United States)

    Puopolo, G; Cimmino, A; Palmieri, M C; Giovannini, O; Evidente, A; Pertot, I

    2014-10-01

    To investigate low molecular weight compounds produced in vitro by Lysobacter capsici AZ78 and their toxic activity against sporangia of plant pathogenic oomycetes. Assays carried out in vitro showed that L. capsici AZ78 drastically inhibits the growth of plant pathogenic oomycetes. Accordingly, the preventive application of culture filtrates of L. capsici AZ78 on grapevine and tomato plants reduced the infections, respectively, caused by Plasmopara (Pl.) viticola and Phytophthora infestans. The subsequent chemical analysis of the culture filtrates of L. capsici AZ78 by spectroscopic (essentially 1D and 2D (1)H NMR and (13)C NMR and ESI MS spectra) and optical methods led to the identification of the 2,5-diketopiperazine cyclo(L-Pro-L-Tyr) that inhibited the development of P. infestans sporangia in vitro and on tomato leaves. Furthermore, a genomic region with high sequence identity with genes coding for a hybrid polyketide synthase and nonribosomal peptide synthetase was detected in L. capsici AZ78. Lysobacter capsici AZ78 produces cyclo(L-Pro-L-Tyr) in vitro that was effective in killing the sporangia of P. infestans and Pl. viticola in vitro. Moreover, this low molecular weight compound prevents the occurrence of late blight lesions when applied on tomato leaves. The application of L. capsici AZ78 cells or its own culture filtrates effectively controls both P. infestans and Pl. viticola. Cyclo(L-Pro-L-Tyr) produced by L. capsici AZ78 is toxic against sporangia of both these oomycetes. These data enforce the potential in the use of Lysobacter members for the control of plant pathogenic oomycetes and provide the basis for the development of new low-impact fungicides based on cyclo(L-Pro-L-Tyr). © 2014 The Society for Applied Microbiology.

  7. Corrosion mechanism and model of pulsed DC microarc oxidation treated AZ31 alloy in simulated body fluid

    Energy Technology Data Exchange (ETDEWEB)

    Gu Yanhong, E-mail: ygu2@alaska.edu [Department of Mechanical Engineering, University of Alaska Fairbanks, Fairbanks, AK 99775 (United States); Chen Chengfu [Department of Mechanical Engineering, University of Alaska Fairbanks, Fairbanks, AK 99775 (United States); Bandopadhyay, Sukumar [Department of Mining Engineering, University of Alaska Fairbanks, Fairbanks, AK 99775 (United States); Ning Chengyun [College of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China); Zhang Yongjun [Department of Mining Engineering, University of Alaska Fairbanks, Fairbanks, AK 99775 (United States); Guo Yuanjun [College of Materials Science and Engineering, South China University of Technology, Guangzhou 510640 (China)

    2012-06-01

    This paper addresses the effect of pulse frequency on the corrosion behavior of microarc oxidation (MAO) coatings on AZ31 Mg alloys in simulated body fluid (SBF). The MAO coatings were deposited by a pulsed DC mode at four different pulse frequencies of 300 Hz, 500 Hz, 1000 Hz and 3000 Hz with a constant pulse ratio. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests were used for corrosion rate and electrochemical impedance evaluation. The corroded surfaces were examined by X-ray diffraction (XRD), X-ray fluorescence (XRF) and optical microscopy. All the results exhibited that the corrosion resistance of MAO coating produced at 3000 Hz is superior among the four frequencies used. The XRD spectra showed that the corrosion products contain hydroxyapatite, brucite and quintinite. A model for corrosion mechanism and corrosion process of the MAO coating on AZ31 Mg alloy in the SBF is proposed.

  8. Improvement in the corrosion protection and bactericidal properties of AZ91D magnesium alloy coated with a microstructured polypyrrole film

    Directory of Open Access Journals (Sweden)

    A.D. Forero López

    2018-03-01

    Full Text Available In this work hollow rectangular microtubes of polypyrrole (PPy films were potentiostatically electrodeposited on magnesium alloy AZ91D in salicylate solution. The substrate was previously anodized under potentiostatic conditions in a molybdate solution in order to improve the adherence of polymer. Finally the duplex film was modified by the incorporation of silver species. The obtained coatings were characterized by scanning electron microscopy (SEM, X-ray diffraction (XRD and X-ray photoelectron spectroscopies (XPS and the antimicrobial activity against the bacteria Escherichia coli was evaluated. The corrosion protection properties of the coatings were examined in Ringer solution by monitoring the open circuit potential, polarization techniques and electrochemical spectroscopy (EIS. The duplex coating presents an improved anticorrosive performance with respect to the PPy film. The best results concerning corrosion protection and antibacterial activity were obtained for the silver-modified composite coating. Keywords: Polypyrrole, Duplex coating, AZ91D alloy, Corrosion resistance, Antibacterial properties

  9. Corrosion mechanism and model of pulsed DC microarc oxidation treated AZ31 alloy in simulated body fluid

    International Nuclear Information System (INIS)

    Gu Yanhong; Chen Chengfu; Bandopadhyay, Sukumar; Ning Chengyun; Zhang Yongjun; Guo Yuanjun

    2012-01-01

    This paper addresses the effect of pulse frequency on the corrosion behavior of microarc oxidation (MAO) coatings on AZ31 Mg alloys in simulated body fluid (SBF). The MAO coatings were deposited by a pulsed DC mode at four different pulse frequencies of 300 Hz, 500 Hz, 1000 Hz and 3000 Hz with a constant pulse ratio. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) tests were used for corrosion rate and electrochemical impedance evaluation. The corroded surfaces were examined by X-ray diffraction (XRD), X-ray fluorescence (XRF) and optical microscopy. All the results exhibited that the corrosion resistance of MAO coating produced at 3000 Hz is superior among the four frequencies used. The XRD spectra showed that the corrosion products contain hydroxyapatite, brucite and quintinite. A model for corrosion mechanism and corrosion process of the MAO coating on AZ31 Mg alloy in the SBF is proposed.

  10. The oxidation resistance and ignition temperature of AZ31 magnesium alloy with additions of La2O3 and La

    International Nuclear Information System (INIS)

    Zhao, Shizhe; Zhou, Hong; Zhou, Ti; Zhang, Zhihui; Lin, Pengyu; Ren, Luquan

    2013-01-01

    Highlights: ► Using lanthanum and lanthanum oxide (La 2 O 3 ) can improve oxidation resistance of magnesium alloy. ► La 2 O 3 is as effective as La in affecting both alloy microstructure and oxidation resistance. ► The optimum La concentration in alloy is ∼0.7 wt.%. ► We analyzed the oxidation kinetics of AZ31 alloy with both additions. - Abstract: We investigate the oxidation resistance of AZ31 magnesium alloy with additions of La and La oxide (La 2 O 3 ). The contributor is the practical La content in alloy. Both La and La 2 O 3 are effective in improving the oxidation resistance of Mg alloys. The samples with La content of ∼ 0.7 wt.% possess the best resistance to oxidation of all. Oxide scale, ignition temperature and oxidation kinetics are analyzed. However, higher La content is detrimental to the oxidation resistance.

  11. PHYSICAL CHARACTERIZATION OF VITREOUS STATE LABORATORY AY102/C106 AND AZ102 HIGH LEVEL WASTE MELTER FEED SIMULANTS (U)

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, E

    2005-03-31

    The objective of this task is to characterize and report specified physical properties and pH of simulant high level waste (HLW) melter feeds (MF) processed through the scaled melters at Vitreous State Laboratories (VSL). The HLW MF simulants characterized are VSL AZ102 straight hydroxide melter feed, VSL AZ102 straight hydroxide rheology adjusted melter feed, VSL AY102/C106 straight hydroxide melter feed, VSL AY102/C106 straight hydroxide rheology adjusted melter feed, and Savannah River National Laboratory (SRNL) AY102/C106 precipitated hydroxide processed sludge blended with glass former chemicals at VSL to make melter feed. The physical properties and pH were characterized using the methods stated in the Waste Treatment Plant (WTP) characterization procedure (Ref. 7).

  12. Evaluation of self-healing ability of Ce–V conversion coating on AZ31 magnesium alloy

    Directory of Open Access Journals (Sweden)

    Xiao Jiang

    2016-09-01

    Full Text Available This study investigated the influence of cerium nitrate in vanadate solutions on the properties of Ce–V conversion coatings on AZ31 magnesium alloys, and evaluated the self-healing behavior of the Ce–V conversion coating for AZ31 magnesium alloy. The results showed that the additions of cerium nitrate prevented pentavalent vanadium from reducing to tetravalent vanadium in the coatings during conversion reaction process. Adding appropriate cerium nitrate to vanadate solution led to a thicker coating with a more compact CeVO4 layer. The corrosion behavior of the Ce–V conversion coating was investigated by the electrochemical tests and the scratch immersion test in 3.5 wt.% NaCl solution. The self-healing ability of the coating was confirmed from all tests. The surface analysis revealed that the self-healing effect of the Ce–V conversion coating was only provided by the release and migration of vanadium compounds.

  13. Effect of antimony, bismuth and calcium addition on corrosion and electrochemical behaviour of AZ91 magnesium alloy

    International Nuclear Information System (INIS)

    Zhou Wei; Aung, Naing Naing; Sun Yangshan

    2009-01-01

    This study investigated the effect of antimony, bismuth and calcium addition on the corrosion and electrochemical behaviour of AZ91 magnesium alloy in 3.5% NaCl solution. Techniques including constant immersion, electrochemical potentiodynamic polarisation, scanning electron microscopy (SEM), energy dispersed spectroscopy (EDS) and X-ray diffraction (XRD) were used to characterise electrochemical and corrosion properties and surface topography. It was found that corrosion attack occurred preferentially on Mg 3 Bi 2 and Mg 3 Sb 2 particles while Mg 17 Al 8 Ca 0.5 and Mg 2 Ca phases showed no detrimental effect on corrosion. Combined addition of small amounts of bismuth and antimony to the AZ91 alloy resulted in significant increase in corrosion rate

  14. The research on the effect of MgCO{sub 3} on the grain refinement in AZ31 magnesium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Gao, S.Y.; Cui, J.Z.; Li, Q.C.; Zhang, Z.Q. [Key Laboratory of Electromagnetic Processing of Materials, Ministry of Education, Northeastern University, Shenyang (China)

    2010-08-15

    The effect of MgCO{sub 3} addition on the as-cast microstructure of AZ31 magnesium alloy has been widely investigated. The results show that the average grain size of the {alpha}-Mg grain in AZ31 magnesium alloy decreases from about 570 {mu}m to 100 {mu}m by the addition of 0.6 wt.% MgCO{sub 3} as gain refiner at 760 C. Based on the analysis of EDS, theoretical calculation of E{sub bind} and Gibbs free energy, we esteem that grain refiner mechanism is mainly attributed to the generation of Al{sub 4}C{sub 3}, which can be serviced as nucleation site and restrain grain boundary from growing and transferring. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  15. Application of heat treatment and hot extrusion processes to improve mechanical properties of the AZ91 alloy

    Directory of Open Access Journals (Sweden)

    T. Reguła

    2010-04-01

    Full Text Available The main aim of this paper is to evaluate the effects of hot working (extrusion and hest treatment on room temperature mechanical properties of magnesium-based AZ91 alloy. The results were compared with as-cast condition. The examined material had been obtained by gravity casting to permanent moulds and subsequently subjected to heat treatment and/or processed by extrusion at 648 K. Microstructural and mechanical properties of properly prepared specimens were studied. Rm, Rp02 and A5 were determined from tensile tests. Brinell hardness tests were also conducted. The research has shown that hot working of AZ91 alloy provides high mechanical properties unattainable by cast material subjected to heat-treatment. The investigated alloy subjected to hot working and subsequently heat-treated has doubled its strength and considerably improved the elongation - compared with the as-cast material.

  16. The effects of zirconium and beryllium on microstructure evolution, mechanical properties and corrosion behaviour of as-cast AZ63 alloy

    International Nuclear Information System (INIS)

    Jafari, Hassan; Amiryavari, Peyman

    2016-01-01

    Alloying elements are able to strongly modify the microstructure characteristics of Mg–Al–Zn alloys which dominate mechanical and corrosion properties of the alloys. In this research, the individual effects of Zr and Be additions on the microstructure, mechanical and corrosion properties of as-cast AZ63 alloy were explored. The results revealed that the addition of Zr leads to microstructure refinement in as-cast AZ63 alloy, resulting in improved tensile and hardness properties. 0.0001 and 0.001 wt% Be containing cast AZ63 alloy exhibited microstructure coarsening, while morphological alteration from sixford symmetrical to irregular shape grain was observed for the alloy containing 0.01 and 0.1 wt% Be. No specific Be compound was detected. In addition, mechanical properties of AZ63 alloy containing Zr was improved due to the microstructure modification, while Be containing alloy responded reverse behaviour. The corrosion resistance of AZ63 alloy was improved after the addition of Zr and Be due to the grain refinement and passivation effects, respectively. However, when the Zr content exceeds 0.5 wt%, the formation of Al 2 Zr affected the corrosion resistance. In other words, AZ63–0.5Zr alloy provided the lowest corrosion rate.

  17. Cambio en azúcares fermentables en la remolacha azucarera almacenada en atmósferas aerobia y anaerobia para la producción de etanol

    Directory of Open Access Journals (Sweden)

    Juan Manuel Vargas Ramírez

    2014-06-01

    Full Text Available Los métodos de almacenamiento de largo plazo son necesarios para preservar los azúcares fermentables en la remolacha y permitir el funcionamiento exitoso a lo largo del año en las plantas procesadoras para la obtención de etanol. Se estudió el almacenamiento anaeróbico de la remolacha azucarera como una alternativa al almacenamiento convencional en pilas a la intemperie utilizado actualmente en fábricas de azúcar de remolacha. Los resultados experimentales indican una pérdida de <15% en el total de los azúcares fermentables en la remolacha azucarera almacenada anaeróbicamente durante 14 semanas a 4 °C. Después de 14 semanas de almacenamiento, 99 ± 4% de los azúcares fermentables iniciales fueron preservados en la remolacha almacenada en condiciones aeróbicas a 4 °C. El almacenamiento aeróbico y anaeróbico de remolacha azucarera a 25 ° C conserva 82 ± 9 y 48 ± 11% del contenido de azúcar fermentable, respectivamente. Los azúcares fermentables y etanol en exudados contribuyeron insignificantemente (<3% para el rendimiento del etanol global de remolacha azucarera después del almacenamiento.

  18. The effect of Ca and RE elements on the precipitation kinetics of Mg17Al12 phase during artificial aging of magnesium alloy AZ91

    International Nuclear Information System (INIS)

    Amir Esgandari, B.; Mehrjoo, H.; Nami, B.; Miresmaeili, S.M.

    2011-01-01

    Highlights: → Ca and RE elements decrease the precipitation rate during aging of AZ91 alloy. → Precipitation kinetics and mechanism during aging of the alloys were studied. → Effect of Ca and RE on creep properties of age hardened AZ91 alloy was studied. - Abstract: The effect of simultaneous alloying with Ca and rare earth (RE) elements on the age hardening kinetics of AZ91 was studied through the fitting of the Johnson-Mehl-Avrami (JMA) equation. The results showed that the addition of both Ca and RE elements not only suppress discontinuous precipitation of the Mg 17 Al 12 phase during the age hardening process, but also decrease the alloy hardness. Fitting the JMA equation to the experimental data indicated that the phase transformation during age hardening of an alloy variant containing both Ca and RE (at 170 deg. C and 190 deg. C) and standard AZ91 (at 170 deg. C) takes place by the nucleation of precipitates on dislocations. In contrast, the precipitation during age hardening of AZ91 at 190 deg. C occurs via nucleation at grain boundaries. Although it was observed that the creep strength of age hardened specimens are lower than that of the as cast specimens, but age hardening treatment has lower deleterious influence on the creep resistance of the alloy containing Ca and RE in comparison with conventional AZ91. This may be ascribed to the decreased precipitation rate resulting from the addition of both Ca and RE elements.

  19. Application of YAG Laser TIG Arc Hybrid Welding to Thin AZ31B Magnesium Alloy Sheet

    Science.gov (United States)

    Kim, Taewon; Kim, Jongcheol; Hasegawa, Yu; Suga, Yasuo

    A magnesium alloy is said to be an ecological material with high ability of recycling and lightweight property. Especially, magnesium alloys are in great demand on account of outstanding material property as a structural material. Under these circumstances, research and development of welding process to join magnesium alloy plates are of great significance for wide industrial application of magnesium. In order to use it as a structure material, the welding technology is very important. TIG arc welding process is the most ordinary process to weld magnesium alloy plates. However, since the heat source by the arc welding process affects the magnesium alloy plates, HAZ of welded joint becomes wide and large distortion often occurs. On the other hand, a laser welding process that has small diameter of heat source seems to be one of the possible means to weld magnesium alloy in view of the qualitative improvement. However, the low boiling point of magnesium generates some weld defects, including porosity and solidification cracking. Furthermore, precise edge preparation is very important in butt-welding by the laser welding process, due to the small laser beam diameter. Laser/arc hybrid welding process that combines the laser beam and the arc is an effective welding process in which these two heat sources influence and assist each other. Using the hybrid welding, a synegistic effect is achievable and the disadvantages of the respective processes can be compensated. In this study, YAG laser/TIG arc hybrid welding of thin magnesium alloy (AZ31B) sheets was investigated. First of all, the effect of the irradiation point and the focal position of laser beam on the quality of a weld were discussed in hybrid welding. Then, it was confirmed that a sound weld bead with sufficient penetration is obtained using appropriate welding conditions. Furthermore, it was made clear that the heat absorption efficiency is improved with the hybrid welding process. Finally, the tensile tests

  20. Microstructure and mechanical properties of AZ91 tubes fabricated by Multi-pass Parallel Tubular Channel Angular Pressing

    OpenAIRE

    Hooman Abdolvand; Ghader Faraji; Javad Shahbazi Karami

    2017-01-01

    Parallel Tubular Channel Angular Pressing (PTCAP) process is a novel recently developed severe plastic deformation (SPD) method for producing ultrafine grained (UFG) and nanograined (NG) tubular specimens with excellent mechanical and physical properties. This process has several advantageous compared to its TCAP counterparts. In this paper, a fine grained AZ91 tube was fabricated via multi pass parallel tubular channel angular pressing (PTCAP) process. Tubes were processed up to three passes...

  1. Magnesium alloy AZ63A reinforcement by alloying with gallium and using high-disperse ZrO2 particles

    Directory of Open Access Journals (Sweden)

    J. Khokhlova

    2016-12-01

    Full Text Available The aim of this work was to obtain an experimental magnesium alloy by remelting standard AZ63A alloy with addition of gallium ligatures and ZrO2 particles. This allowed reinforcement of alloy and increase its hardness and Young's modulus. The chemical analysis of this alloy shows two types of structures which are evenly distributed in volume. Thus we can conclude that reinforcing effect is the result of formation of intermetallic phase Mg5-Ga2.

  2. A New Factor in American Destiny: Visions of Porfirio Díaz and the Politics of “Logical Paternalism”

    Directory of Open Access Journals (Sweden)

    Jason Ruiz

    2011-12-01

    Full Text Available This essay interprets American representations of dictator Porfirio Díaz in relation to the “economic conquest” of Mexico that took place during his long rule (1876–1911, a period known as the “Porfiriato,” in which Americans invested more than $1 billion. No single person inspired as much attention from travelers, reporters, and photographers during the late nineteenth and early twentieth centuries as Díaz, and their visions of the President helped to shape perceptions of Mexico as a desirable field in which to expand US capitalism and influence. Travelers clamored to meet him and his sophisticated young wife, and their travelogues were rich with descriptions of such encounters. Reporters, dazzled by the rapid transformation of Mexico during his 35-year rule, described Díaz in such terms as “the Mexican Wizard” and “the maker of modern Mexico” until the very end of his regime. Photographers, working in a relatively new medium, amassed a huge body of works devoted to the dictator; even at an advanced age late in his rule, the President’s image adorned postcards and commemorative cartes-de-visite that posited him in heroic and hypermasculine terms (not unlike those of his US counterpart, Theodore Roosevelt. Ultimately, this essay argues that representations like these reflected American desires for a Mexican body politic that was amenable to economic and social transformation under the inextricable banners of “progress” and US capitalism. Prevailing images of Díaz and his family suggested that Mexico was as friendly to foreign investors as it was to foreign visitors.

  3. In vitro and in vivo studies of biodegradable fine grained AZ31 magnesium alloy produced by equal channel angular pressing.

    Science.gov (United States)

    Ratna Sunil, B; Sampath Kumar, T S; Chakkingal, Uday; Nandakumar, V; Doble, Mukesh; Devi Prasad, V; Raghunath, M

    2016-02-01

    The objective of the present work is to investigate the role of different grain sizes produced by equal channel angular pressing (ECAP) on the degradation behavior of magnesium alloy using in vitro and in vivo studies. Commercially available AZ31 magnesium alloy was selected and processed by ECAP at 300°C for up to four passes using route Bc. Grain refinement from a starting size of 46μm to a grain size distribution of 1-5μm was successfully achieved after the 4th pass. Wettability of ECAPed samples assessed by contact angle measurements was found to increase due to the fine grain structure. In vitro degradation and bioactivity of the samples studied by immersing in super saturated simulated body fluid (SBF 5×) showed rapid mineralization within 24h due to the increased wettability in fine grained AZ31 Mg alloy. Corrosion behavior of the samples assessed by weight loss and electrochemical tests conducted in SBF 5× clearly showed the prominent role of enhanced mineral deposition on ECAPed AZ31 Mg in controlling the abnormal degradation. Cytotoxicity studies by MTT colorimetric assay showed that all the samples are viable. Additionally, cell adhesion was excellent for ECAPed samples particularly for the 3rd and 4th pass samples. In vivo experiments conducted using New Zealand White rabbits clearly showed lower degradation rate for ECAPed sample compared with annealed AZ31 Mg alloy and all the samples showed biocompatibility and no health abnormalities were noticed in the animals after 60days of in vivo studies. These results suggest that the grain size plays an important role in degradation management of magnesium alloys and ECAP technique can be adopted to achieve fine grain structures for developing degradable magnesium alloys for biomedical applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. En híbrida mezcolanza: Exile and Cultural Anxiety in Alirio Díaz Guerra’s Lucas Guevara

    Directory of Open Access Journals (Sweden)

    Jeffrey Browitt

    2005-03-01

    Full Text Available The novel Lucas Guevara, written by the Colombian exile, Alirio Díaz Guerra, was first published in New York in 1914. It is considered to be the earliest novel about Latin American immigration to the United States written in Spanish. This fact alone merits its study. A second edition was published in 2001 along with a critical-biographical introduction, which presents the novel as the precursor of a developing genre of Hispanic immigrant literature centred on the naïve Latin American migrant who arrives in the United States inspired by the opportunities which the metropolis supposedly affords, but who nevertheless suffers a series of misfortunes because of the inability to adapt to the new culture. On the level of overt content, the novel is a lachrymose, stereotypical and conventional denunciation of the supposed evils of an amoral US society and the libertine and materialistic values underpinning it. But on a much deeper level, a picture emerges of Díaz Guerra himself as a displaced, disenchanted intellectual exile who suffers (or has suffered an acute cultural and class anxiety in the transition from a patrician Arcadia to the heart of capitalist, industrial modernity. Through a reading of the narrative voice, and by extension the implied author, we witness his difficult coming to terms with a highly-charged New York society (in comparison to his homeland, not only because of the sexual liberation brought on by secular modernization, but also because of the close proximity of volatile, eroticised bodies on the over-crowded Lower East Side of New York, the scene of the novel and Díaz Guerra’s point of entry into the United States. The novel also provides an occasion to contrast how Díaz Guerra deals with the condition of exile, in contrast to that most emblematic of Latin American political refugees, José Martí.

  5. 241-AZ-101 Mixer Pump Demonstration Test Gamma Cart Acceptance Test Procedure and Quality Test Plan (ATP and QTP)

    International Nuclear Information System (INIS)

    WHITE, D.A.

    2000-01-01

    Shop test of the sludge mobilization cart system to be used in the AZ-101 Mixer Pump Demonstration Test Tests hardware and software. This procedure involves testing the Instrumentation involved with the Gamma Cart System, local and remote, including depth indicators, speed controls, interface to data acquisition software and the raising and lowering functions. This Procedure will be performed twice, once for each Gamma Cart System. This procedure does not test the accuracy of the data acquisition software

  6. 241-AZ-101 Mixer Pump Demonstration Test Gamma Cart Acceptance Test Procedure and Quality Test Plan (ATP and QTP)

    International Nuclear Information System (INIS)

    WHITE, D.A.

    2000-01-01

    Shop Test of the Gamma Cart System to be used in the AZ-101 Mixer Pump Demonstration Test. Tests hardware and software. This procedure involves testing the Instrumentation involved with the Gamma Cart System, local and remote, including: depth indicators, speed controls, interface to data acquisition software and the raising and lowering functions. This Procedure will be performed twice, once for each Gamma Cart System. This procedure does not test the accuracy of the data acquisition software

  7. Corrosion performance of atmospheric plasma sprayed alumina coatings on AZ31B magnesium alloy under immersion environment

    OpenAIRE

    D. Thirumalaikumarasamy; K. Shanmugam; V. Balasubramanian

    2014-01-01

    Plasma sprayed ceramic coatings are successfully used in many industrial applications, where high wear and corrosion resistance with thermal insulation are required. The alumina powders were plasma sprayed on AZ31B magnesium alloy with three different plasma spraying parameters. In the present work, the influence of plasma spray parameters on the corrosion behavior of the coatings was investigated. The corrosion behavior of the coated samples was evaluated by immersion corrosion test in 3.5 w...

  8. High Level Waste Feed Delivery AZ-101 Batch Transfer to the Private Contractor Transfer and Mixing Process Improvements

    International Nuclear Information System (INIS)

    DUNCAN, G.P.

    2000-01-01

    The primary purpose of this business case is to provide Operations and Maintenance with a detailed transfer process review for the first High Level Waste (HLW) feed delivery to the Privatization Contractor (PC), AZ-101 batch transfer to PC. The Team was chartered to identify improvements that could be implemented in the field. A significant penalty can be invoked for not providing the quality, quantity, or timely delivery of HLW feed to the PC

  9. Preparation and properties of plasma sprayed NiAl10 and NiAl40 coatings on AZ91 substrate.

    Czech Academy of Sciences Publication Activity Database

    Kubatík, Tomáš František; Lukáč, František; Stoulil, J.; Ctibor, Pavel; Průša, F.; Stehlíková, K.

    2017-01-01

    Roč. 319, June (2017), s. 145-154 ISSN 0257-8972 R&D Projects: GA ČR(CZ) GP14-31538P Institutional support: RVO:61389021 Keywords : Nickel aluminide * AZ91 magnesium alloy * Plasma spraying * Potentiodynamic measurement * Adhesion strength Subject RIV: JJ - Other Materials OBOR OECD: Materials engineering Impact factor: 2.589, year: 2016 http://www.sciencedirect.com/science/article/pii/S0257897217303250

  10. Evaluación de la mezcla de ametrina + clomazone en caña de azúcar

    Directory of Open Access Journals (Sweden)

    Valent\\u00EDn A. Esqueda

    2001-01-01

    Full Text Available caña de azúcar. Se estableció un experimento en el Rancho Casablanca, Municipio de Puente Nacional, en el estado de Veracruz, México, para evaluar la toxicidad ocasionada por la mezcla de los herbicidas ametrina + clomazone a las variedades de caña de azúcar MEX-79-431, MEX-69-290, MEX-68- P23 y CP-72-2086. Se evaluaron cuatro tratamientos de control de malezas: 1. Ametrina + clomazone (1200 + 800 g/ha, 2. Ametrina + clomazone (1800 + 1200 g/ha, 3. Ametrina + 2,4-D (1225 + 650 g/ha y 4. Testigo limpio. Los herbicidas se aplicaron cuando la caña de azúcar tenía entre dos y cuatro hojas. La mezcla de ametrina + clomazone ocasionó blanqueamiento del follaje en todas las variedades de caña de azú- car. El área con blanqueamiento, varió entre el 36,3 y 47,5% con la dosis mas alta de esta mezcla; entre el 25 y 39,4%, con la dosis menor y prácticamente desapareció a los 45 días despu és de la aplicación. A su vez, la mezcla de ametrina + 2,4- D no ocasionó blanqueamiento. La toxicidad ocasionada por la mezcla de ametrina + clomazone no afectó el número de hojas por planta, el número de tallos en 2 m lineales y la altura de las plantas. Tampoco fueron afectados el rendimiento de tallos y el contenido de sacarosa

  11. Grain refinement of AZ91D alloy by intensive melt shearing and its persistence after remelting and isothermal holding

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    Zuo Yubo

    2013-01-01

    Full Text Available Intensive melt shearing has a significant grain refining effect on some light alloys. However, the persistence of the grain refining effect during isothermal holding and remelting is still unclear, although it is very important for the practical application. In this study, intensive melt shearing was achieved in a twin-screw mechanism to investigate its grain refining effect on AZ91D magnesium alloy. The refinement mechanism was discussed and the persistence of grain refinement after remelting and isothermal holding was also studied. A Zeiss imaging system with polarized light was used for quantitative measurement of grain size. The results show that the intensive melt shearing has a significant grain refining effect on AZ91D magnesium alloy. With the application of intensive melt shearing, the grain size of AZ91D magnesium alloy can be reduced from 530 μm (for a typical as-cast microstructure to 170 μm, which is about 70% size reduction. The grain refinement achieved by the intensive melt shearing can be partially kept after isothermal holding and remelting. It is believed that the refinement effect was mainly due to the finer and well dispersed oxide particles formed by high intensive shearing. The smaller size of oxide particles and their slow motion velocity in the sheared melt could make important contributions to the remained grain refinement.

  12. Influence of Route-R on wrought magnesium AZ61 alloy mechanical properties through equal channel angular pressing

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    Muralidhar Avvari

    2014-06-01

    Full Text Available A new fundamental route entitled ‘Route-R’ is introduced to refine the grains in the material through Equal Channel Angular Pressing (ECAP process. In route R, specimen is inverted to the original position in each ECAP pass. In the present work, AZ61 alloy is processed using ECAP process for three different fundamental routes mainly route A, route Bc, and route R. ECAP experiment is carried out on AZ61 alloy at lower temperature of 483 K up to two passes. Microstructural characterization is evaluated on unECAPed and ECAPed specimens for three routes. Average grain size of the alloy is to be reduced from 66 μm to 16 μm, 14.1 μm and 10 μm for route A routes Bc, and route R respectively. Vickers microhardness of the alloy is found to be 60 HV for as received material. This microhardness of the alloy is increased to 71 HV, 72 HV, and 74 HV for route A, route Bc, and route R respectively. Mechanical properties of the AZ61 alloy are observed to be route R is providing maximum YS, UTS, and percentage elongation than other route A and route Bc. Tensile fracture topography of the specimen is analyzed using three different routes for two passes.

  13. Corrosion behaviour of AZ91D and AM50 magnesium alloys with Nd and Gd additions in humid environments

    Energy Technology Data Exchange (ETDEWEB)

    Arrabal, R., E-mail: raularrabal@quim.ucm.es [Departamento de Ciencia de Materiales, Facultad de Ciencias Quimicas, Universidad Complutense, 28040 Madrid (Spain); Matykina, E.; Pardo, A.; Merino, M.C. [Departamento de Ciencia de Materiales, Facultad de Ciencias Quimicas, Universidad Complutense, 28040 Madrid (Spain); Paucar, K. [Gabinete de Corrosion, Facultad de Ingenieria Quimica y Textil, Universidad Nacional de Ingenieria, Cod. Postal 25, Lima (Peru); Mohedano, M.; Casajus, P. [Departamento de Ciencia de Materiales, Facultad de Ciencias Quimicas, Universidad Complutense, 28040 Madrid (Spain)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Mg alloys with additions of Nd and Gd were exposed to high humidity atmosphere. Black-Right-Pointing-Pointer The increase of Nd or Gd diminished the effect of micro-galvanic couples. Black-Right-Pointing-Pointer Corrosion resistance of the AM50 alloy improved with the addition of Nd or Gd by 43%. Black-Right-Pointing-Pointer Nd and Gd had no significant effect on the corrosion resistance of the AZ91D alloy. - Abstract: AM50 and AZ91D alloys modified with rare earths (RE) were evaluated under atmospheric conditions. Nd and Gd additions resulted in formation of Al{sub 2}RE and Al-Mn-RE compounds and reduction of the fraction of {beta}-phase. According to surface potential maps, RE-containing intermetallics were more noble than the {beta}-phase, but less than Al-Mn inclusions. As a result, the action of micro-galvanic couples depended on the added amount of RE and the initial alloy microstructure. Nd or Gd additions improved the corrosion resistance of the AM50 alloy by up to 43%, but had no significant effect on the corrosion resistance of the AZ91D alloy.

  14. Corrosion behaviour of AZ91D and AM50 magnesium alloys with Nd and Gd additions in humid environments

    International Nuclear Information System (INIS)

    Arrabal, R.; Matykina, E.; Pardo, A.; Merino, M.C.; Paucar, K.; Mohedano, M.; Casajús, P.

    2012-01-01

    Highlights: ► Mg alloys with additions of Nd and Gd were exposed to high humidity atmosphere. ► The increase of Nd or Gd diminished the effect of micro-galvanic couples. ► Corrosion resistance of the AM50 alloy improved with the addition of Nd or Gd by 43%. ► Nd and Gd had no significant effect on the corrosion resistance of the AZ91D alloy. - Abstract: AM50 and AZ91D alloys modified with rare earths (RE) were evaluated under atmospheric conditions. Nd and Gd additions resulted in formation of Al 2 RE and Al–Mn–RE compounds and reduction of the fraction of β-phase. According to surface potential maps, RE-containing intermetallics were more noble than the β-phase, but less than Al–Mn inclusions. As a result, the action of micro-galvanic couples depended on the added amount of RE and the initial alloy microstructure. Nd or Gd additions improved the corrosion resistance of the AM50 alloy by up to 43%, but had no significant effect on the corrosion resistance of the AZ91D alloy.

  15. Investigation on the Effect of Pulsed Energy on Strength of Fillet Lap Laser Welded AZ31B Magnesium Alloys

    Science.gov (United States)

    Salleh, M. N. M.; Ishak, M.; Aiman, M. H.; Idris, S. R. A.; Romlay, F. R. M.

    2017-09-01

    AZ31B magnesium alloy have been hugely applied in the aerospace, automotive, and electronic industries. However, welding thin sheet AZ31B was challenging due to its properties which is easily to evaporated especially using conventional fusion welding method such as metal inert gas (MIG). Laser could be applied to weld this metal since it produces lower heat input. The application of fiber laser welding has been widely since this type of laser could produce better welding product especially in the automotive sectors. Low power fiber laser was used to weld this non-ferrous metal where pulse wave (PW) mode was used. Double fillet lap joint was applied to weld as thin as 0.6 mm thick of AZ31B and the effect of pulsed energy on the strength was studied. Bond width, throat length, and penetration depth also was studied related to the pulsed energy which effecting the joint. Higher pulsed energy contributes to the higher fracture load with angle of irradiation lower than 3 °

  16. Laser surface forming of AlCoCrCuFeNi particle reinforced AZ91D matrix composites

    Science.gov (United States)

    Meng, Guanghui; Yue, T. M.; Lin, Xin; Yang, Haiou; Xie, Hui; Ding, Xu

    2015-07-01

    Traditionally, the laser melt injection (LMI) technique can only be used for forming ceramic particles reinforced metal matrix composites (MMCs) for enhancing surface properties of lightweight engineering materials. In this research, the LMI method was employed to form metal particles reinforced MMCs on AZ91D instead. This was viable because of the unique properties of the AlCoCrCuFeNi high-entropy alloy (HEA) metal particles used. The large difference in melting point between the HEA and the substrate material (AZ91D), and the limited reaction and the lack of fusion between the HEA and Mg have made it possible that a metal particles reinforced AZ91D composite material was produced. The reason of limited reaction was considered mainly due to the relatively high mixing enthalpy between the HEA constituent elements and Mg. Although there was some melting occurred at the particles surface with some solute segregation found in the vicinity close to the surface, intermetallic compounds were not observed. With regard to the wear resistance of the MMCs, it was found that when the volume fraction of the reinforcement phase, i.e. the HEA particles, reached about 0.4, the wear volume loss of the coating was only one-seventh of that of the substrate material.

  17. Corrosion fatigue behaviors of two biomedical Mg alloys - AZ91D and WE43 - In simulated body fluid.

    Science.gov (United States)

    Gu, X N; Zhou, W R; Zheng, Y F; Cheng, Y; Wei, S C; Zhong, S P; Xi, T F; Chen, L J

    2010-12-01

    Magnesium alloys have been recently developed as biodegradable implant materials, yet there has been no study concerning their corrosion fatigue properties under cyclic loading. In this study the die-cast AZ91D (A for aluminum 9%, Z for zinc 1% and D for a fourth phase) and extruded WE43 (W for yttrium 4%, E for rare earth mischmetal 3%) alloys were chosen to evaluate their fatigue and corrosion fatigue behaviors in simulated body fluid (SBF). The die-cast AZ91D alloy indicated a fatigue limit of 50MPa at 10⁷ cycles in air compared to 20MPa at 10⁶ cycles tested in SBF at 37°C. A fatigue limit of 110MPa at 10⁷ cycles in air was observed for extruded WE43 alloy compared to 40MPa at 10⁷ cycles tested in SBF at 37°C. The fatigue cracks initiated from the micropores when tested in air and from corrosion pits when tested in SBF, respectively. The overload zone of the extruded WE43 alloy exhibited a ductile fracture mode with deep dimples, in comparison to a brittle fracture mode for the die-cast AZ91D. The corrosion rate of the two experimental alloys increased under cyclic loading compared to that in the static immersion test. Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  18. Factores de competitividad de la agroindustria de la caña de azúcar en México

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    Noé Aguilar Rivera

    2011-01-01

    Full Text Available La industria azucarera de México integra actividades agrícolas de crecimiento, cosecha y transporte de caña a la producción de azúcar estándar y refinada, con otros productos y subproductos. Para competir en una economía global, es importante establecer criterios de desempeño para reducir costos de producción en términos de competitividad técnica, productividad y eficiencia en aspectos como rendimientos, caña de azúcar y agroindustrial por hectárea y de fábrica. En este artículo se discuten algunos indicadores de competitividad económica y técnica de la industria de caña de azúcar mexicana, con metodologías de benchmarking y diamante de Porter. Los resultados mostraron que son numerosos los factores técnicos y económicos que limitan el crecimiento, debido a que la industria mexicana se ha mantenido no competitiva y requiere mejorar e innovar en la reducción de costos, sobre todo en materia prima, cosecha y transporte. También está la diversificación, con base en los subproductos, como residuos de cosecha, bagazo, melazas, lodo de filtros y vinazas; esto es de gran importancia como fuente renovable de energía y materias primas.

  19. Temporal regulation of foregut development by HTZ-1/H2A.Z and PHA-4/FoxA.

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    Dustin L Updike

    2006-09-01

    Full Text Available The histone variant H2A.Z is evolutionarily conserved and plays an essential role in mice, Drosophila, and Tetrahymena. The essential function of H2A.Z is unknown, with some studies suggesting a role in transcriptional repression and others in activation. Here we show that Caenorhabditis elegans HTZ-1/H2A.Z and the remodeling complex MYS-1/ESA1-SSL-1/SWR1 synergize with the FoxA transcription factor PHA-4 to coordinate temporal gene expression during foregut development. We observe dramatic genetic interactions between pha-4 and htz-1, mys-1, and ssl-1. A survey of transcription factors reveals that this interaction is specific, and thus pha-4 is acutely sensitive to reductions in these three proteins. Using a nuclear spot assay to visualize HTZ-1 in living embryos as organogenesis proceeds, we show that HTZ-1 is recruited to foregut promoters at the time of transcriptional onset, and this recruitment requires PHA-4. Loss of htz-1 by RNAi is lethal and leads to delayed expression of a subset of foregut genes. Thus, the effects of PHA-4 on temporal regulation can be explained in part by recruitment of HTZ-1 to target promoters. We suggest PHA-4 and HTZ-1 coordinate temporal gene expression by modulating the chromatin environment.

  20. High-Speed Rolling of AZ31 Magnesium Alloy Having Different Initial Textures

    Science.gov (United States)

    Onuki, Yusuke; Hara, Kenichiro; Utsunomiya, Hiroshi; Szpunar, Jerzy A.

    2015-02-01

    It is known that magnesium alloys can be rolled up to a large thickness reduction and develop a unique texture when the rolling speed is high (>1000 m/min). In order to understand the texture formation mechanism during high-strain-rate deformation, high-speed rolling of AZ31 magnesium alloy samples having different initial textures was conducted. The main components of the textures after the rolling were the RD-split basal, which consisted of 10°-20° inclining basal poles from the normal direction toward the rolling direction of the sheet, regardless of the different initial textures. With preheating at 473 K, all the samples were rolled without cracking while all were cracked when preheating was not applied. The optical micrographs and EBSD measurements showed a significant amount of twins and the cracks that developed along the shear bands consisted with laminated twins. Based on the texture simulation using the visco-plastic self-consistent model, it is concluded that the rapid development of the RD-split basal component from the initial basal alignment along the transverse direction was attributable to the tension twinning, The effect of the initial texture on the crack formation can be explained by the activation of the twinning system.