Eksplorasi Teknologi Big Data Hadoop Untuk Sistem Aplikasi Berbasis Komunitas

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Gede Karya

2017-11-01

Full Text Available Pada tahun 2014, telah dikembangkan aplikasi pembukuan untuk usaha mikro dan kecil (UMK berbasis mobile cloud. Aplikasi tersebut dikembangkan dengan teknologi mobile berbasis Android, teknologi web dan web service serta menggunakan basis data MySQL sebagai back-end. Dengan populasi usaha mikro sebanyak 55,1 juta unit usaha di Indonesia dan terus berkembang, maka aplikasi pembukuan UMK berpotensi digunakan oleh banyak user. Hal ini menimbulkan kebutuhan akan layanan pengelolaan data yang sangat besar baik volume maupun pertumbuhannya. Oleh karena itu, perlu dipersiapkan sisi back-end dengan teknologi big-data processing untuk menjamin ketersediaan dan kehandalan layanan kepada pengguna UMK. Makalah ini fokus pada eksplorasi teknologi big-data Hadoop yang saat ini banyak diterapkan untuk aplikasi komunitas seperti: Google, Facebook, Twitter, dan Amazon. Pembahasan diawali dengan studi tentang Hadoop dan ekosistemnya, kemudian merumuskan pola adopsi untuk aplikasi berbasis komunitas. Setelah itu pola dan teknologi tersebut diterapkan untuk mengembangkan back-end aplikasi pembukuan UMK berbasis mobile cloud. Hasil studi dan penerapannya menunjukkan bahwa Hadoop dapat diadopsi pada aplikasi pembukuan UMK khususnya HBase. Untuk memudahkan akses dan meminimalkan usaha modifikasi, maka akses HBase dari aplikasi dapat menggunakan Apache Phoenix Java Data Base Connectivity (JDBC dari beberapa opsi yang tersedia.

Identifikasi Materi Mata Kuliah Teknologi Kendaraan Lanjut

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Joko Sriyanto

2010-10-01

Full Text Available Tujuan dari penelitian ini adalah untuk menentukan isi/materi mata kuliah Teknologi Kendaraan Lanjut (TKL di Jurusan Pendidikan Teknik Otomotif Fakultas Teknik Universitas Negeri Yogyakarta. TKL merupakan salah satu mata kuliah yang dikembangkan oleh Jurdiknik Otomotif FT UNY untuk mewadahi perkembangan terkini teknologi otomotif yang akan mulai diberlakukan pada tahun ajaran 2009/2010.Permasalahan di atas dicari jawabannya dengan mengembangkan konsensus dari expert panel yaitu dosen dan praktisi bidang otomotif menggunakan metode Delphi. Metode Delphi adalah suatu metode yang digunakan untuk memperoleh pendapat dan konsensus dari sekelompok ahli (expert secara sistematis melalui serangkaian kuesioner tanpa harus mempertemukan mereka secara langsung/tatap muka. Dua putaran Delphi akan digunakan untuk mengumpulkan data dan mengembangkan konsensus. Hasil penelitian menunjukkan bahwa teknologi terbaru di bidang otomotif yang harus diberikan kepada mahasiswa berdasarkan konsensus dari para ahli di bidang otomotif adalah: (1 Common rail, (2 ASV (Advanced Safety Vehicle, (3 Intellegent Tester seri 2, (4 Hybrid System, dan (5 Smart Entry System.

ADOPSI TEKNOLOGI PERTANIAN UNTUK PEMBANGUNAN PEDESAAN: SEBUAH KAJIAN SOSIOLOGIS

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Apri Kuntariningsih

2014-10-01

Full Text Available ABSTRAKTeknologi pertanian diharapkan dapat membantu petani untuk meningkatkan kesejahteraan. Berbagai teknologi pertanian telah diperkenalkan dan disebarluaskan kepada petani, tetapi sebagian besar petani pedesaan masih dianggap tertinggal dari masyarakat lain. Kajian ini bertujuan  mempelajari kegagalan penyebaran teknologi pertanian dalam mengentaskan kemiskinan di daerah pedesaan. Berdasar kajian ini nantinya diharapkan mampu merumuskan strategi dari asepk sosiologis terkait penyebaran teknologi pertanian. Hasil kajian ini menunjukkan bahwa faktor sosial, ekonomi dan kelembagaan perlu mendapat perhatian lebih dari pembuat kebijakan baik di tingkat nasional dan lokal dalam rangka untuk meningkatkan dampak diseminasi teknologi pertanian dalam peningkatan kesejahteraan petani di daerah pedesaan.ABSTRACTAgricultural technology is expected to help farmers to improve welfare. Various agricultural technologies have been introduced and disseminated to farmers, but to some extents, peasants are still considered lag behind other communities. This paper is conducted investigate the failure of agricultural technologies dissemination in alleviating poverty in rural areas. This strudy showssocial, economic and institutional factors that need more attention from policy makers both at national and local levels in orde to improve impact of agricultural technology dissemination in escalating farmers’ welfare in rural areas. 

Katalog Penjualan Rumah Berbasis Android Menggunakan Teknologi Augmented Reality dan Virtual Reality

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Alders Paliling

2017-02-01

Full Text Available Penerapan teknologi augmented reality kian diminati oleh pihak produsen untuk memasarkan produk  yang dihasilkan. Teknologi augmented reality mampu meproyeksikan objek dua dimensi ataupun tiga dimensi kedalam lingkungan nyata. Teknologi virtual reality mampu membawa pengguna masuk kedalam lingkungan virtual sehingga pengguna merasa berada dalam lingkungan virtual. Penelitian ini menggunakan teknologi augmented reality yang mampu memproyeksikan objek tiga dimensi rumah sehingga katalog menjadi lebih nyata,  dan teknologi virtual reality yang membuat pengguna berinteraksi langsung dengan objek tiga dimensi rumah dan merasa berada di dalam rumah. Aplikasi yang dibangun memanfaatkan sensor accelerometer yang tertanam dalam perangkat mobile android yang memungkinkan pengguna melihat seisi ruangan dengan memiringkan perangkat mobile android kekiri dan kekanan. Jumlah kamera virtual yang digunakan berjumlah lima yang diletakkan di ruang tamu, ruang keluarga, ruang kamar utama, ruang kamar anak, dan ruang dapur. Aplikasi ini berjalan pada platform android dan menggunakan personal komputer sebagai server yang menyimpan data informasi rumah. Dengan adanya aplikasi ini pengguna dapat merasakan suasana berbeda dalam melihat sebuah katalog. . Kata kunci—Augmentd Reality, Virtual Reality, Katalog, Android

Rancang Bangun Sistem Pilkades Menggunakan Teknologi Smart Card Sebagai Kartu Pemilih

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I Putu Indra Permana

2016-08-01

Full Text Available Pemilihan Kepala Desa (Pilkades merupakan proses yang tidak terpisahkan dari Negara Indonesia sebagai negara demokrasi. Pilkades saat ini masih menggunakan sistem pemungutan suara (voting secara konvensional, menggunakan media kertas untuk melakukan proses pemilihan. Pelaksanaan sistem voting konvensional tersebut mempunyai banyak kelemahan seperti menghitung hasil voting relatif lebih lama dan menggunakan perhitungan manual. Perkembangan dan kemajuan teknologi informasi saat ini dapat dimanfaatkan untuk mendukung pelaksanaan voting Pilkades secara lebih baik yang menjadi solusi cerdas akan kemajuan teknologi yang dapat menggantikan sistem voting konvensional, yaitu dengan media sistem elektronik voting (e-voting menggunakan teknologi smart card sebagai kartu pemilih. Sistem dikemas dalam bentuk aplikasi yang dipasang/di-install pada komputer dan reader/writer tools sebagai media untuk membaca/menulis pada smart card. Sistem e-voting Pilkades dengan teknologi smart card telah berhasil dijalankan dan menghasilkan dashboard hasil voting Pilkades dengan menunjukkan jumlah voting dalam bentuk angka, persentase (%, grafik dan diagram.

Proceedings of the Sixth Seminar on Computation in Nuclear Science and Technology; Lokakarya Komputasi dalam Sains dan Teknologi Nuklir VI

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-07-01

National Atomic Energy Agency (BATAN) had held the Sixth Seminar on Computation in Nuclear Science and Technology on January 16-17, 1996. The seminar is an event for information exchange among interest society in computation, modeling, and simulation. Similar as previous seminar in the past year, there were also non-BATAN and university-bound presenters and participants whose interest are in the field of science and technology. Examining the papers presented in this seminar, it shows that beside digging the so called classical computation methods, some papers brought relatively new topics like the determination and influence of chaos, neural network method, and expert system. Judging from the variety of the topics, one can conclude that interests in computation and its application are growing stronger in Indonesia.

Measurement and Analysis of Output Radiation Dose on X-Ray Device over 10 Years at Hospitals in Medan City

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Herty Afrina Sianturi

2018-01-01

Adhikari, Suraj Raj. 2012. Effect And Application      Of Ionization Radiation (X-Ray In Living  Organism. Kaski: Volume 3.The Himalaya  Physics. Badan Pengawas Tenaga Nuklir, Peraturan Kepala BAPETEN No. 8 Tahun 2011  tentang Keselamatan Radiasi dalam Penggunaan Pesawat Sinar-X Radiologi Diagnostik dan Intervensional, 2011. BAPETEN, 1999, Surat Keputusan Kepala Bapeten nomor 01/Ka-Bapeten/V-99 tentang Kesehatan terhadap radiasi pengion, Jakarta BATAN, 2005, Disain Penahan Ruang Sinar – X, Pusdiklat, BATAN, Jakarta Bushong, Steward C. 2013. Radologic Science for Technologists. 10th edition.United State of  America : CV. Mosby Company. Kramer, H. M., dan Selbach, H. J. 2008. Extension of the Range of Definition of the Practical Peak Voltage up to 300 kV. The British Journal of  Radiologhy (81:693-698. Rassad, S. dkk, Radiologi Diagnostik, Fakultas Kedokteran Universitas Indonesia Rumah Sakit Dr Cipto Mangunkusumo, Jakarta (2000. Suryanto, Sigit Bachtiar. 2011. Analisis Pembentukan Gambar Dan Batas Toleransi Uji Kesesuaian Pada Pesawat Sinar-X Diagnostik. Prosiding Seminar Penelitian Dan Pengelolaan Perangkat Nuklir. Trikasjono, T. dkk. 2009. Analisis Keselamatan Pesawat Sinar-X di Instalasi Radiologi Rumah Sakit Umum daerah Sleman Yogyakarta. Prosiding Seminar Nasional Sains dan Teknologi Nuklir PTNBR – BATAN. Vassileva, J. 2004. A Phantom for Dose Image Quality Optimization in Chest Radiography. The British Journal of Radiologhy 75:837-842. Wadianto, Azis Muslim. 2017. Uji Akurasi Tegangan Tinggi Alat Rontgen Radiography Mobile. INOVASI, Volume XIX Nomor 1,Januari 2017

Teknologi Hijau Warisan Nenek Moyang di Tanah Parahyangan

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Handajani Asriningpuri

2015-08-01

Full Text Available Masyarakat tradisional umumnya tidak berkebutuhan majemuk; sederhana; bersahaja; dan menerima keberadaan alam sebagai sahabat, bahkan merupakan bagian kehidupannya. Keadaan ini terjadi di Kampung Naga, Garut, Tanah Parahyangan sebagai suatu kearifan lokal. Dari sudut pandang arsitektur, hal tersebut menginspirasi konsep perancangan. Penelitian ini, membuktikan dari sudut pandang ilmu lingkungan dan arsitektur tentang adanya kaitan kearifan lokal dengan teknologi hijau yang menerapkan “green concept”(ZEB – Zero Energy Building dan 3R – Reuse, Reduce, Recycle. Metoda yang dilakukan adalah metoda diskriptif kualitatif berdasarkan data primer dan sekunder hasil observasi lapangan dan literatur. Kemudian dikaji melalui teori Aarsitektur dan pendekatan Teknologi Hijau, dan dibuktikan melalui Greenship Home Assestment (ketentuan GBCI – Green Building Council Indonesia Hasil kajian dan temuan pemahaman kearifan lokal, akan menginspirasi, membangkitkan semangat hijau, dan menambah wawasan bagiperancang bangunan. Bagi para regulator (pemerintah daerah kearifan lokal harus di pertahankan dan dapat menyadarkan penduduk kampung Naga untuk tetap berkehidupan sesuai ketentuan yang di yakini. Kata Kunci : Green Concept, Kampung Naga, Kearifan lokal, Teknologi Arsitektur

Penerapan Framework COBIT untuk Identifikasi Tingkat Kematangan Tata Kelola Teknologi Informasi: Studi Kasus di Fasilkom Unwidha

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Agustinus Suradi

2017-07-01

Full Text Available Perkembangan IT sebagai media komunikasi data hingga saat ini berkembang sangat pesat. Peranan teknologi informasi dalam suatu lembaga sangat krusial, namun  masalah  yang sering terjadi di lembaga/ instansi adalah penggunaan teknologi informasi yang ternyata tidak sesuai dengan harapan, oleh karena itu diperlukan tata kelola terhadap penggunaan teknologi informasi. Permasalahan yang dihadapi di Fasilkom Unwidha adalah adanya ketidak puasan layanan IT yang diberikan, terdapatnya gangguan layanan yang tidak segera diatasi, adanya koordinasi maintenance infrastruktur IT yang kurang optimal. Sehingga perlu adanya evaluasi terhadap tata kelola teknologi informasi yang diberikan untuk penyelarasan dengan tujuan organisasi agar visi yang diharapkan dapat tercapai. Penelitian ini membahas tentang kondisi tata kelola teknologi informasi di Fasilkom Unwidha, dan sejauh mana telah menerapkan tata kelola teknologi informasi yang baik. Metode analisis yang digunakan dalam penelitian ini adalah dengan menggunakan  framework Control Objectives for Information and Related Technology (COBIT. Hasil dari analisis ini berupa tingkat kematangan tata kelola  teknologi informasi  yang  mencerminkan  kondisi  tata  kelola  teknologi informasi  di  Fakultas Ilmu Komputer Unwidha. Tingkat kematangan dengan mengacu pada maturity level yang disediakan kerangka kerja COBIT, diperoleh nilai  kematangan 2,84 yaitu pada level Defined Process. Sistem memiliki ruang lingkup Business Goals sebanyak 13, IT Goals sebanyak 18, IT Process sebanyak 30 proses dan 4 Domain.

Hubungan Multitasking Teknologi Informasi Terhadap Produktivitas Kerja (Studi Kasus: Mahasiswa ITS

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Galang Arga Marendha

2017-01-01

Full Text Available Pada era globalisasi saat ini cara hidup individu umumnya para remaja dan dewasa yang selalu bergerak cepat dalam mendapatkan informasi terbaru agar tidak tertinggal dari yang lain memungkinkan melakukan pekerjaan secara bersamaan. Mayoritas dari individu-individu menganggap melakukan banyak pekerjaan sekaligus dapat digunakan sebagai solusi yang tepat. Dengan kemajuan teknologi saat ini dan perilaku seperti itu, banyak sekali contoh pekerjaan yang dilakukan secara bersama-sama seperti halnya mengirim e-mail saat sedang menonton televisi maupun membuat laporan saat rapat. Teknologi informasi tersebut merupakan komponen yang mendukung peningkatan produktivitas kerja. Dalam hasil dari penelitian ini didapatkan perbandingan antara skenario 1 dengan 2 dan skenario 1 dengan 3 berpengaruh terhadap produktivitas kerja karena adanya penambahan tugas me-resume video dan mengerjakan 10 soal matematika, sedangkan perbandingan skenario 2 dengan skenario 3 didapatkan dari hasil wawancara terhadap responden bahwa tidak adanya pengaruh pada produktivitas kerja dikarenakan penambahan tugas me-resume video skenario 2 lebih sulit dari tugas me-resume video skenario 3 serta penambahan 10 soal matematika tidak menjadi masalah dalam pengerjaan skenario 3. Dalam hasil hubungan multitasking teknologi informasi skenario 1 didapatkan hasil 33,1% terhadap produktivitas kerja, kemudian hubungan multitasking teknologi informasi skenario 2 didapatkan hasil 23,6% terhadap produktivitas kerja, dan hubungan multitasking teknologi informasi skenario 3 didapatkan hasil 24,8% terhadap produktivitas kerja. Sehingga dari pengerjaan skenario 2 dan 3 produktivitas kerja responden menurun dikarenakan adanya tambahan kuantitas pengerjaan.

DAMPAK NEGATIF PERKEMBANGAN TEKNOLOGI INFORMATIKA DAN KOMUNIKASI DAN CARA ANTISIFASINYA

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I Gede Ratnaya

2011-03-01

Full Text Available Sampai saat ini perkembangan ilmu pengetahuan telah menghantarkan masyarakat menuju babak baru yaitu babak yang memanfaatkan peralatan-peralatan yang merupakan hasil dari teknologi. Penggunaan tenaga manusia yang semakin hari semakin kecil volumenya sering kali menyebabkan orang kehilangan pekerjaannya karena tugasnya telah tergantikan oleh peralatan atau mesin. Sebagai sarana penyampaian informasi dan komunikasi, komputer bisa dipakai sebagai sarana berinternetan. Lewat internet orang bisa mencari bermacam-macam informasi dan berkomunikasi. Peran yang dapat diberikan oleh aplikasi teknologi informasi ini adalah mendapatkan informasi untuk kehidupan pribadi seperti informasi tentang kesehatan, hobi, rekreasi, dan rohani. Selain memberikan keuntungan, ternyata peralatan teknologi informasi dan komunikasi juga memberikan dampak negatif bagi penggunanya. Dampak negatif tersebut muncul sebagai akibat dari penggunaan yang salah atau tidak bertanggung jawab dari yang menggunakan. Beberapa dampak negatif tersebut adalah 1. Anak lebih banyak menghabiskan waktu menonton TV ketimbang melakukan hal lainnya (seperti belajar dan olah raga, 2. Anak kehilangan kemampuan berbaur dengan masyarakat dan cenderung nyaman dengan kehidupan online, 3 Adanya pelanggaran hak cipta, 4.  Kejahatan di internet, 5. Penyebaran virus komputer, dan 6. Pornografi, perjudian, penipuan, tayangan kekerasan. Adapun cara mengatasi dampak-dampak negatif tersebut adalah : 1. Gunakan teknologi untuk menjalin hubungan dengan orang yang sudah dikenal, 2. Cari komunitas positif  yang sering melakukan pertemuan didunia nyata, 3. Perlunya penegakkan hukum yang berlaku dengan dibentuknya polisi internet, 4. Menghindari pemakaian telepon seluler yang berfitur canggih oleh anak-anak dibawah umur dan lebih mengawasi penggunaan telepon seluler, 5. Perbanyak membaca buku-buku yang bersifat edukatif dan bersifat keimanan serta aplikasi komputer yang bersifat mendidik, dan 6. Perlunya pengaturan

Menakar Peranan Pustakawan dalam Implementasi Teknologi Informasi di Perpustakaan

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Agung Nugrohoadhi

2013-12-01

Full Text Available Pustakawan dalam era teknologi informasi ini perlu mempersiapkan diri dalam menghadapi era perpustakaan digital. Kemampuan dalam beradaptasi dengan lingkungan ini amat diperlukan karena pemustaka sendiri tentunya  mengharapkan layanan yang berorientasi pada teknologi maju sehingga keakuratan data dan kecepatan informasi dapat diperoleh. Khususnya pada perpustakaan yang melayani lembaga perguruan tinggi akan selalu berkembang baik jumlah koleksi, fasilitas maupun pengembangan profesionalisme para pustakawan. Dalam mendukung aktivitas  kegiatan ini perpustakaan  diharapkan akan selalu sigap dalam menyiapkan kebutuhan pemustaka sehingga koleksi yang disediakan mampu mengimbangi kebutuhan informasi yang diperlukan.

Sæbeopera som Forestillingsgenererende Teknologi

DEFF Research Database (Denmark)

Waltorp, Karen

2013-01-01

Gennem en række empiriske eksempler fra Mauretanien, Danmark og Sydafrika analyserer artiklen dramaserier på tv som en art social teknologi, der tillader infor- manterne at generere forestillinger om andre liv og andre verdener, der på én gang er langt væk og tæt på. 'Soap operas' produceret i USA...

Studi dan Uji Coba Teknologi Bluetooth sebagai Alternatif Komunikasi Data Nirkabel

OpenAIRE

Yulia, Yulia; Santoso, Leo Willyanto

2004-01-01

In Bahasa Indonesia : Bluetooth adalah suatu teknologi baru yang mulai dikenal dan digunakan. Teknologi ini memberikan Perubahan yang signifikan terhadap peralatan elektronik yang kita gunakan. Jika kita melihat sekeliling kita dimana keyboard dihubungkan pada komputer. Demikian juga halnya dengan printer, mouse, monitor dan lain sebagainya. Semua peralatan itu dihubungkan dengan menggunakan kabel. Akibatnya terjadi masalah banyak kabel yang dibutuhkan di kantor, rumah atau tempat-tempat...

RANCANGAN TATAKELOLA TEKNOLOGI INFORMASI UNTUK PABRIK PUPUK

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Kridanto Surendro

2008-01-01

Full Text Available Many believe that information technology will be the major driver for economic wealth in the 21st century, but investing in information technology implementation on supporting corporate business process have a huge risk of failure because of the huge investment involved. There is a need of a comprehensive and structured IT governance from design until monitoring phase. This paper was trying to propose an IT governance model for a fertilizer company as a strategic state company in Indonesia’s macro economics. It identified current IT implementation, governance model requirements aligned with corporate resources and vision and mission base on COBIT standard. COBIT Standard is used because it has a good combination of the width and the depth of IT governance processes compared to other standards. Identification of current IT process maturity level showed that 50% of COBIT IT processes have maturity scale at 2, 37,5% at 1, and 12,5% at 3. None of current IT process maturity level had the same level with the expected one, so all of the process had a gap to be closed. The action in closing the maturity gap need a hard work for PT XYZ management. There are actions about defining policies and procedures, documentation of the defined policies and procedures, and a routine reviews of it. Abstract in Bahasa Indonesia: Teknologi Informasi diyakini sebagai pendukung utama tercapainya tujuan perusahaan di abad 21 ini, namun investasi penerapan teknologi informasi dalam menunjang proses bisnis suatu perusahaan mempunyai resiko kegagalan yang cukup besar dikarenakan nilai investasi yang menyertainya cukup besar. Untuk itu diperlukan suatu tatakelola teknologi informasi yang komprehensif dan terstruktur dari mulai perancangan sampai pengawasannya. Makalah ini mencoba memberikan suatu usulan model tatakelola teknologi informasi di sebuah pabrik pupuk yang merupakan salah satu BUMN yang mempunyai nilai strategis dalam menunjang makro ekonomi di Indonesia

Blockchain kan forbedre sundhedsvæsnet

DEFF Research Database (Denmark)

Damsgaard, Jan

2017-01-01

Med blockchain-teknologi får vi en mulighed for at gentænke vores udskældte sundheds-IT-systemer.......Med blockchain-teknologi får vi en mulighed for at gentænke vores udskældte sundheds-IT-systemer....

PENILAIAN TEKNOLOGI UNTUK MENENTUKAN POSISI INDUSTRI PESAING

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Wahyu Susihono

2013-02-01

Full Text Available PT Sumiati Ekspor Internasinal bergerak pada usaha penjualan handycraft yang dipasok oleh lima industri kecil binaannya. Perusahaan akan melakukan privatisasi dalam waktu dekat, manajer pusat menginginkan ada satu industri kecil mengambil alih pengelolaan. Pihak manajemen perusahaan menghendaki ada penilaian teknologi secara internal dan eksternal kepada lima industri kecil binaanya sebagai dasar pengambilan keputusan. Dalam Penelitian ini dilakukan penilaian kepada semua industri kecil pemasokhandycraft dengan pendekatan model teknometrik, yaitu memperkirakan derajat sophistication komponen teknologi, evaluasi tiap komponen technoware, humanware, inforware dan organware dan menilai state-of-the-art. Kuesioner yang disebarkan dari lima industri kecil diolah menggunakan pairwise comparison Analytic Hierarchy Process”(AHP, dilanjutkan dengan perhitungan TCC (Technology Contribution Coefficient. Penilaian internal perusahaan dilakukan dengan model DEA (data envelopment analysis. Hasil akhir TCC dan DEA secara kuantitatif dibandingkan. Hasil TCC (Technology Contribution Coefficient secara berturut-turut dari industry yang memperoleh nilai terbesar adalah Industri Maharani 52.23%, Industri Bestari 42.87%, Industri Priyo 41.51%, Industri Rizky 32.66%, Industri Teguh 31.93%. Unsur kontribusi teknologi terbesar yang dihasilkan industri Maharani adalah organware, sedangkan empat perusahaan lainnya humanware. Unsur teknologi yang harus dikembangkan dalam jangka pendek untuk semua industri kecil adalah technoware. Hasil penilaian internal perusahaan dengan model DEA menunjukan bahwa industri Maharani mempunyai rangking tertinggi, sedangkan Industri Rizki pada rangking terrendah. Model teknometrik dikombinasi pairwise comparison AHP dan DEA dapat membantu perusahaan besar melakukan penilaian teknologi kepada industri kecil sejenis. Kata Kunci : penilaian teknologi, model teknometrik, pairwise comparison AHP, DEA   Abstract Sumiati Export International

Dialogmøte om teknologi for trenging av fisk i merd

OpenAIRE

Henriksen, Kristian; Sunde, Leif Magne; Digre, Hanne; Svendsen, Erik; Rundtop, Per; Erikson, Ulf Gøran

2013-01-01

SINTEF Fiskeri og havbruk arrangerte den 19. mars 2013, i samarbeid med Fiskeri- og havbruksnæringens forskningsfond (FHF), et dialogmøte med fokus på teknologi for trenging av fisk i merd. Under møtet ble status for gjeldene teknologi og operasjoner for trenging av fisk i merd, samt resultater fra forskningsprosjekter tilknyttet trengeprosessen, presentert. Videre ble det samlet innspill om utfordringer tilknyttet trenging av fisk i produksjons- og ventemerd fra oppdrettsbedrifter, leverandø...

Kinerja Perusahaan Terkait dengan Terapan dan Kompetensi Teknologi Informasi

Directory of Open Access Journals (Sweden)

Eko Purwanto

2014-06-01

Full Text Available AbstractInvestment in information technology (IT implementation in organizations tends to increase manufacturing in Indonesia. Various studies show that implementation of IT that is applied has a major impact on company performance. This study aims to answer, whether at manufacturing organizations in Indonesia, the implementation of IT is applied and competencies have an impact, both directly and indirectly to the performance. The sample of this study is a company registered in the Department of Industry and Trade in East Java, which apply information and communication technologies in local area network. There are 117 companies with 500 employees or more participated in this study. Data were analyzed using SEM, with the application of SPSS and AMOS. The results of this study indicate that the more complete implementation of information technology applied in the company, and the higher the competence of knowledge in information technology, the higher the company's organizational performance is achieved.Keywords: Implementation IT, Competence IT, Organization Performance.AbstrakPenerapan investasi di bidang teknologi informasi (TI dalam organisasi perusahaan cenderung meningkat di Indonesia. Berbagai penelitian menunjukkan bahwa implementasi TI yang diterapkan memiliki dampak besar pada kinerja perusahaan. Penelitian ini bertujuan untuk menjawab, apakah implementasi kompetensi TI di organisasi perusahaan di Indonesia memiliki dampak, baik secara langsung maupun tidak langsung terhadap kinerja. Sampel penelitian ini adalah perusahaan yang terdaftar di Departemen Perindustrian dan Perdagangan di Jawa Timur yang mengaplikasikan informasi dan teknologi komunikasi dalam jaringan area lokal. Ada 117 perusahaan dengan 500 karyawan atau lebih berpartisipasi dalam penelitian ini. Data dianalisis dengan menggunakan SEM, dengan aplikasi SPSS dan AMOS. Hasil penelitian ini menunjukkan bahwa implementasi teknologi informasi yang lebih lengkap di perusahaan

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

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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.

IMPLEMENTASI TEKNOLOGI WEB SERVICES PADA APLIKASI PENCARIAN TAKSI

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Debby Erce Sondakh

2016-09-01

Full Text Available Taksi merupakan layanan transportasi yang umum ditemui di daerah perkotaan. Untuk menggunakan layanan taksi pengguna dapat menunggu taksi yang lewat atau memesan melalui telepon. Kendala yang terjadi dari metode ini adalah panggilan telepon tidak tersambung karena operator sedang melayani konsumen lain, posisi taksi yang berada jauh dari konsumen, atau konsumen tidak mengetahui posisinya saat ini dengan tepat. Ketika menunggu taksi di jalan, pencarian taksi dapat memakan waktu lama. Makalah ini memaparkan tentang pengembangan aplikasi pencarian taksi berbasis teknologi Android, menggunakan model proses Rational Unified Process dari pendekatan rekayasa perangkat lunak. Implementasi teknologi web service menghasilkan aplikasi pencarian taksi terdekat yang dapat mengintegrasikan aplikasi berbasis web dengan platform berbeda, dengan aplikasi mobile berbasis sistem operasi Android. Pada aplikasi mobile, pengguna dapat mencari taksi terdekat sesuai perusahaan terdaftar yang dilacak menggunakan GPS dan melihat posisi taksi pada peta dari Google Maps Application Programming Interface, melihat informasi taksi, serta memesan taksi atau membatalkan pemesanan.

PENGARUH MODAL, TENAGA KERJA DAN TEKNOLOGI TERHADAP HASIL PRODUKSI SUSU KABUPATEN BOYOLALI

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Satya Nugroho

2014-09-01

Full Text Available Currently, most of milk in Indonesia should be imported. It is about 78,89 %, and the rest, that is about 22,11% is from local production or local dairy farmers. However, there are some problems faced by the dairy farmers in Kecamatan Musuk. They are capital, workforces, and technology. This study aims at knowing the influence of capital, workforces, and technology to the milk production in Kecamatan Musuk. Ordinary Least Square (OLS was applied for analizing the data. The results show that the regression coefficient values of each independent variable (the variables of capital, workforces, and technology positively influence the production of milk. Based on the T-test (partial, the capital and workforces influence positively and significantly to the production. In addition, technology also has positive effect to the milk production, but it is not significant. Finally, based on F-test, the milk production is influenced by the capital, workforces and technology. It is 87%. Saat ini sebagian besar susu di Indonesia masih harus di impor (sekitar 78,89%, sedangkan 22,11%nya di pasok dari produksi susu domestik yang sebagian besar dihasilkan oleh peternak sapi perah rakyat. Namun ada beberapa permasalaham yang kerap dihadapi oleh peternak sapi perah di Kecamatan Musuk, baik dari segi permodalan, tenaga kerja maupun teknologi yang dipakai.Penelitian ini bertujuan untuk mengetahui seberapa besar pengaruh dari penggunaan faktor produksi modal, tenaga kerja dan teknologi terhadap hasil produksi susu sapi perah di Kecamatan Musuk. Alat analisis yang digunakan adalah analisis regresi berganda atau Ordinary Least Square (OLS.Hasil analisis diperoleh bahwa nilai koefisien regresi masing-masing variabel bebas yaitu variabel Modal, Tenaga Kerja, dan Teknologi berpengaruh secara positif terhadap produksi susu sapi perah. Dari hasil uji-t (parsial modal dan tenaga kerja berpengaruh positif dan signifikan sedangkan teknologi berpengaruh positif namun tidak

SISTEM INFORMASI SECARA ONLINE TUGAS AKHIR MAHASISWA JURUSAN TEKNOLOGI INFORMASI FAKULTAS TEKNOLOGI INFORMASI DAN KOMUNIKASI

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Atmoko Nugroho

2015-08-01

Full Text Available Tugas Akhir is the last stage that will surely passed by students to earn college scholarship. And one of the activities in the field of data administration is to manage file of Tugas Akhir, especially for the submission title and Coordinators of Tugas Akhir. Coordinators are often difficult to check the title of Tugas Akhir, if it has been filed or is pending, and the difficulties in monitoring the load guidance from their Supervisor of Tugas Akhir. This also forms the basis for making an Information System of Tugas Akhir (Sistem Informasi Tugas Akhir with the aim of assisting Jurusan Teknologi Informasi and students take this. Sistem Informasi Tugas Akhir called SITA also be made online this method applying Prototype system development. Prototype method according to Pressman has experienced several stages, namely: collection needs (listen to customers, design (built / REVISE mock-up and evaluation of prototypes (customer test-drives a mock-up. The collection needs to be done, among others, the acquisition of data. The data used in this information system is the data of Tugas Akhir of Jurusan Teknologi Informasi. The next stage in the design, researchers uses planning tool in the form of Unified Modeling Language system (UML and developed using the PHP programming language. System of web-based information created a purpose to be accessible without being restricted by time and place, whereas the benefit derived is facilitated student and coordinator duties in management of Tugas Akhir.

PENGARUH KESESUAIAN TUGAS-TEKNOLOGI, KUALITAS INFORMASI, DAN KUALITAS SISTEM TERHADAP KINERJA INDIVIDU PENGGUNA SISTEM ERP

OpenAIRE

WIJAYA OEI, SUFENNY

2016-01-01

2016 PENGARUH KESESUAIAN TUGAS-TEKNOLOGI, KUALITAS INFORMASI, DAN KUALITAS SISTEM TERHADAP KINERJA INDIVIDU PENGGUNA SISTEM ERP THE EFFECT OF TASK-TECHNOLOGY FIT, INFORMATION QUALITY, AND SYSTEM QUALITY TO ERP SYSTEM???S USER PERFORMANCE Sufenny Wijaya Oei Abdul Hamid Habbe Muhammad Achyar Ibrahim Penelitian ini bertujuan untuk menguji pengaruh kesesuaian tugas-teknologi, kualitas informasi, dan kualitas sistem terhadap kinerja individu pengguna sistem Enterpr...

Hjelmkamera som opmærksomhedsunderstøttende teknologi

DEFF Research Database (Denmark)

Bøhm, Mikkel; Hagedorn-Rasmussen, Peter; Nickelsen, Niels Christian

2016-01-01

Anvendelsen af en relativt simpel teknologi i form af et hjelmkamera kan understøtte og ændre opmærksomhed under og efter håndteringen af en operativ indsats. Hjelmkameraet er fastgjort til den overordnede leder fra brandvæsenet (indsatslederen). Gennem hjelmkameraet er det muligt at opnå indsigt...

REAKTOR INNOVATIVE MOLTEN SALT (IMSR DENGAN SISTEM KESELAMATAN PASIF MENYELURUH

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Andang Widiharto

2015-04-01

Full Text Available Pengembangan Teknologi Reaktor Nuklir pada masa mendatang mengarah pada peningkatan aspek keselamatan, peningkatan pendayagunaan bahan bakar, reduksi limbah radioaktif, ketahanan terhadap proliferasi bahan-bakar nuklir dan peningkatan aspek ekonomi. reaktor Innovative Molten Salt (IMSR adalah reaktor nuklir yang menggunakan bahan bakar cair berupa garam lebur fluoride (7LiF-ThF4-UF4-MaFx. Reaktor IMSR didesain sebagai reaktor pembiak termal, yaitu membiakkan U-233 dari Th-232. Hal ini untuk menjawab permasalahan sustainabilitas ketersedian sumber daya bahan bakar nuklir dan reduksi limbah radioaktif. Dalam aspek keselamatan, desain reaktor IMSR memiliki sifat inherent safe, yaitu koefisien umpan balik daya yang negatif serta memiliki fitur-fitur keselamatan pasif. Fitur-fitur keselamatan pasif terdiri dari sistem shutdown pasif, sistem pendinginan pasif pasca shutdown serta sistem pendinginan pasif untuk produk fisi. Kecelakaan yang berpotensi terjadi pada IMSR, yaitu kecelakaan kehilangan aliran bahan bakar, kecelakaan kehilangan aliran pendingin, kecelakaan kehilangan kemampuan pengambilan kalor serta kecelakaan kerusakan integritas sistem reaktor, dapat ditangani sepenuhnya secara pasif hingga mencapai kondisi shutdown selamat. Kata kunci: keselamatan pasif, inherent safe, IMSR   The next Nuclear Reactor Technology developments are directed to the increasing of the aspects of safety, fuel utility, radioactive waste reduction, proliferation retention and economy. Innovative Molten Salt Reactor (IMSR is a nuclear reactor design that uses fluoride molten salt (7LiF-ThF4-UF4-MaFx. IMSR is designed as a thermal breeder reactor, i.e. to produce U-233 from Th-232. This is the answer of natural nuclear fuel sustainability and radioactive waste problems. In term of safety aspect, IMSR design has inherent safe characteristics, i.e. negative power feedback coefficient, and passive safety features. The passive safety features are passive shutdown

Perancangan Buku Batik Plumpungan Salatiga Dengan Menggunakan Teknologi Augmented Realty Berbasis Android

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Ika Cahya Winata

2017-07-01

Full Text Available Batik Indonesia telah ditetapkan oleh United Nations Educational, Scientific, and Cultural Organization (UNESCO sebagai warisan kemanusiaan untuk budaya lisan dan non-bendawi pada tanggal 2 Oktober 2009. Pengakuan UNESCO ini meliputi teknik, teknologi serta motif batik Indonesia. Indonesia memiliki motif batik yang beragam, dan hampir disetiap daerah memiliki motif batik yang berbeda-beda. Batik Plumpungan Salatiga merupakan karya seni batik kontemporer yang didesain dari batu Prasasti Kota Salatiga. Batik Salatiga ini masih tergolong baru sehingga hanya dikenal oleh golongan tertentu saja. Untuk memperkenalkan batik Plumpungan Salatiga dibutuhkan media informasi yang dapat menarik masyarakat untuk lebih mengenal batik Plumpungan. Media buku dipilih sebagai sarana untuk memberikan informasi tentang batik Plumpungan Salatiga. Seiring dengan berkembangnya teknologi dan permasalahan yang terjadi, Peneliti menggunakan teknologi Augmented Reality sebagai metode dalam memberikan informasi dan menarik minat masyarakat untuk lebih mengenal dan mengetahui tentang batik Plumpungan yang dapat dijalankan pada smartphone Android. Objek penelitian ini adalah batik Plumpungan Salatiga. Metode Augmented Reality ini sudah diujikan kepada pemilik batik dan 20 responden masyarakat didapatkan hasil metode Augmented Reality dapat memberikan informasi mengenai pengaplikasian motif batik Plumpungan Salatiga pada objek 3D yang ditampilkan.

The Communicative Ability of Universiti Teknologi MARA Sarawak's Graduates

Science.gov (United States)

Hassan, Sharifah Zakiah Wan; Hakim, Simon Faizal; Rahim, Mahdalela; Noyem, John Francis; Ibrahim, Sueb; Ahmad, Johnny; Jusoff, Kamaruzaman

2009-01-01

This study explores Universiti Teknologi MARA (UiTM) Sarawak graduating students' oral proficiency, focusing on grammatical accuracy. Oral proficiency in English has always been the benchmark of language proficiency, and in the context of UiTM's language teaching curriculum, efforts to enhance students' oral proficiency are implemented through…

Evaluasi Kesesuaian Struktur Organisasi Pengelola Teknologi Informasi dengan Rencana Jangka Panjang Instansi (Studi Kasus pada Dinas XYZ

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Arief Anwar Shodiq

2012-09-01

Full Text Available Setiap lembaga atau instansi memerlukan teknologi informasi (TI untuk mendukung banyak aktivitas dalam menangani proses bisnisnya. Untuk itu, dibutuhkan pengelolaan teknologi informasi yang ideal dan pembentukan struktur organisasi yang relevan dan dapat menjawab kebutuhan akan kelancaran proses bisnisnya. Tidak terkecuali pada Dinas XYZ sebagai lembaga pemerintahan yang bertugas sebagai pengelola pendidikan dan kebudayaan di tingkat provinsi. Dibutuhkan sebuah struktur organisasi pengelola teknologi informasi yang selaras dengan Rencana Jangka Panjang Instansi untuk mendukung tujuan bisnisnya. Dan ketika perencanaan strategis ini diperbaharui, struktur organisasi juga dituntut untuk diperbaharui mengikuti perubahan kebijakan yang baru. Untuk itu, diperlukan analisis komprehensif mengenai perancangan struktur organisasi yang ideal bagi Dinas XYZ ini, yang meliputi studi pendahuluan yang mengkaji literatur dan kondisi kekinian Dinas XYZ, identifikasi Business Goals, identifikasi IT Goals dan IT Process, penentuan struktur organisasi pengelola TI masa depan beserta tanggung jawab masing-masing bagian, dan analisis gap mengenai kondisi saat ini dan kebutuhan TI masa depan, yang semua itu disesuaikan dengan framework COBIT 4.1 sebagai acuan best practice bagi pengelolaan teknologi informasi.

STUDI DAN UJI COBA TEKNOLOGI BLUETOOTH SEBAGAI ALTERNATIF KOMUNIKASI DATA NIRKABEL

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Yulia Yulia

2004-01-01

Full Text Available Bluetooth is a new emerging technology. This technology gives significant changes for electronic devices that we are using. If we look around, a keyboard is connected to a computer. So does a printer, a mouse, a monitor and so on. This condition creates a problem of so many scattered wires installed in the offices, houses and other places. Another problem is how to inspect the damaging or boken wires. In this paper, we will have a discussion on specific applications of bluetooth such as services provided by the bluetooth technology; bluetooth method - how bluetooth devices make connections in a piconet; as well as investigation on bluetooth protocol stack. Bluetooth has succesfully built easy connection among devices from many vendor without using cables, with less power dan money. By using bluetooth, we can build small network or Piconet, consisting of several devices without cables. Abstract in Bahasa Indonesia : Bluetooth adalah suatu teknologi baru yang mulai dikenal dan digunakan. Teknologi ini memberikan perubahan yang signifikan terhadap peralatan elektronik yang kita gunakan. Jika kita melihat sekeliling kita dimana keyboard dihubungkan pada komputer. Demikian juga halnya dengan printer, mouse, monitor dan lain sebagainya. Semua peralatan itu dihubungkan dengan menggunakan kabel. Akibatnya terjadi masalah banyak kabel yang dibutuhkan di kantor, rumah atau tempat-tempat lainnya. Masalah lain yang ditemui adalah bagaimana menelusuri kabel-kabel yang terpasang jika ada suatu kesalahan atau kerusakan. Bluetooth memperbaiki penggunaan teknologi kabel yang cenderung menyulitkan ini dengan cara menghubungkan beberapa peralatan tanpa menggunakan kabel. Pada karya tulis ini, dibahas aplikasi spesifik bluetooth, antara lain servis-servis apa saja yang disediakan oleh teknologi bluetooth; cara kerja bluetooth yaitu bagaimana bluetooth device melakukan koneksi di dalam sebuah piconet serta bluetooth protocol stack. Bluetooth telah berhasil

Pendampingan Orang Tua pada Anak Usia Dini dalam Penggunaan Teknologi Digital [Parent Mentoring of Young Children in the Use of Digital Technology

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Tesa Alia

2018-01-01

BAHASA INDONESIA ABSTRAK: Kemajuan teknologi memberikan pengaruh signifikan terhadap kehidupan masyarakat termasuk dalam ruang lingkup keluarga. Tidak bisa dipungkiri bahwa kemajuan teknologi saat ini terutama berbasis layanan internet memberikan dampak positif dan juga dampak negatif bagi tumbuh kembang anak dalam keluarga. Anak-anak yang lahir setelah era tahun 1980-an merupakan generasi yang hidup di tengah majunya teknologi informasi dan beragam aplikasi sosial dimulai secara daring (online. Melalui gadget seperti smartphone, laptop, komputer, tablet, dan lain sebagainya memberikan kemudahan bagi anak untuk mengakses jaringan internet di mana pun dan kapan pun. Orang tua berperan penting dalam perkembangan komunikasi anak usia dini, khususnya anak di bawah usia lima tahun. Salah satu upaya orang tua dalam memberikan pendidikan bagi anak dalam keluarga di era digital seperti sekarang adalah dengan memberikan pendampingan dalam penggunaan teknologi bagi anak. Melalui pendampingan tersebut, orang tua dapat mengawasi anak dan mengarahkan konten-konten positif bagi anak untuk menggunakan kemajuan teknologi secara tepat  sesuai dengan masa tumbuh kembang anak.

PENGARUH PEMANFAATAN TEKNOLOGI DAN MODERNISASI SISTEM ADMINISTRASI PERPAJAKAN TERHADAP KEPATUHAN WAJIB PAJAK ORANG PRIBADI

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Titik Aryati

2016-12-01

Keywords: the utilization of technology; modernization of tax administration system; personal taxpayers compliance. Abstrak. Penelitian ini bertujuan untuk menganalisis dampak pemanfaatan teknologi dan modernisasi sistem administrasi perpajakan terhadap kepatuhan wajib pajak pribadi. Variabel independen dalam penelitian ini adalah sistem administrasi perpajakan modern, peraturan pemerintah yang mendukung pemanfaatan teknologi informasi, modernisasi struktur organisasi, modernisasi strategi organisasi, peningkatan sumber daya manusia, good governance, dan whistleblowing system, sedangkan variabel dependennya adalah kepatuhan wajib pajak pribadi. Penelitian ini menggunakan data primer, dengan memberikan kuesioner kepada responden secara online kepada Wajib Pajak orang pribadi dan diisi oleh 180 responden. Metode pengambilan sampel dalam penelitian ini menggunakan metode convenience sampling. Analisis data menggunakan analisis regresi linier berganda. Secara parsial, hasil analisis dan hipotesis menunjukkan bahwa variabel sistem administrasi perpajakan modern, modernisasi strategi organisasi, tata pemerintahan yang baik dan sistem whistleblowing berpengaruh signifikan terhadap kepatuhan wajib pajak pribadi, sedangkan variabel lainnya adalah: peraturan pemerintah, modernisasi struktur organisasi, dan Juga peningkatan sumber daya manusia tidak berdampak terhadap kepatuhan wajib pajak pribadi. Kata Kunci: Pemanfaatan teknolog;  modernisasi sistem administrasi perpajakan; Kepatuhan wajib pajak pribadi.

Analisis Kontribusi Teknologi Dan Produktivitas Di PT. Surya Jaya Tulungagung

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Veronika Yulia Kusumawati

2014-09-01

Full Text Available Abstrak   Teknologi memiliki peranan penting dalam perkembangan berbagai industri.Pentingnya pengetahuan mengenai produktivitas merupakan sarana untuk meningkatkan efisiensi dan efektivitas perusahaan. Metode penelitian ini menggunakan Technology Contribution Coefficient (TCC untuk mengukur kandungan teknologi, pembobotan kriteria dengan Analytical Hierarchy Process (AHP, pengukuran produktivitas dengan American Productivity Center (APC, dan diagram Ishikawa untuk menganalisis permasalahan di PT. Surya Jaya, Tulungagung. Hasil penelitian menyajikan : 1 Skor TCC sebesar 0.49 dengan komponen yang memberikan kontribusi penting secara berturut-turut adalah Humanware>Orgaware>Inforware>Technoware.2 Indeks produktivitas total mengalami kenaikan dari tahun 2011 sampai 2012 dengan nilai sebesar 102,38 dan 104, 3 Indeks profitabilitas total mengalami kenaikan dari tahun 2011 sampai 2012 sebesar 102,57 dan 104,47, 4 Indeks perubahan harga tidak mengalami kenaikan maupun penurunan dari tahun 2011 sampai 2012 dengan nilai 1,00, 5 Strategi yang harus diperbaiki berdasarkan diagram Ishikawa meliputi semua input yaitu bahan baku, tenaga kerja, energi dan modal.   Kata Kunci :Produktivitas, TCC, AHP, APC

Pemodelan Kanal Pada Jaringan Area Tubuh Nirkabel Menggunakan Teknologi Bluetooth

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Rizal Nur Ibrahim

2017-01-01

Full Text Available Pada wireless body area network (WBAN, propagasi radio dari node sensor yang berada di permukaan tubuh manusia sangat kompleks dan unik bila dibandingkan dengan lingkungan yang lain karena tubuh manusia memiliki bentuk yang kompleks dan terdiri dari jaringan tubuh manusia yang berbeda-beda. Oleh karena itu, model kanalnya juga berbeda dengan model kanal di lingkungan lain. Telekomunikasi nirkabel pada aplikasi jaringan area tubuh membutuhkan Medium Access Control (MAC yang dapat beradaptasi, dinamis, dan fleksibel untuk mengatasi berbagai persyaratan aplikasi. MAC yang diusulkan menyesuaikan protokol komunikasi dan parameter yang berdasarkan kepada pencapaian konsumsi daya rendah dan laju data yang tinggi untuk itu dipilih salah satu teknologi komunikasi yang memungkinkan untuk hal ini yaitu Bluetooth. Pada tugas akhir ini akan dilakukan pemodelan kanal pada WBAN untuk mendapatkan bentuk kanal yang sesuai dengan kerakteristik tubuh manusia. Dimana pemodelan kanal ini di fokuskan pada teknologi Bluetooth dengan frekuensi 2,4 GHz. Selain itu, dalam pengerjaannya dilakukan simulasi menggunakan software MATLAB.

Hviler Dansk Økonomi på en Cobb-Douglas teknologi?

DEFF Research Database (Denmark)

Harck, Søren H.

Prisdannelsen og faktorefterspørgslen i Det økonomiske Råds sekretariats SMEC-model af dansk økonomi har siden 1998 været teoretisk begrundet i en underliggende Cobb-Douglas teknologi (i kombination med en antagelse om omkostningsminimering). I SMEC-forgængeren SMEC 94 var det derimod markup...

Perancangan Dan Realisasi Sistem Transmisi Data GPS Menggunakan Teknologi SMS (Short Messaging Service) Sebagai Aplikasi Sistem Personal Tracking

OpenAIRE

DECY NATALIANA

2013-01-01

Abstrak Berprinsip pada pengembangan teknologi dan aplikasi dari sistem penjejakan posisi (tracking), maka dibuatlah sistem personal tracking dengan mentransmisikan data GPS (Global Positioning System) dengan menggunakan teknologi SMS (Short Messaging Service) pada jaringan GSM (Global System for Mobile Communications) sebagai media transmisinya.  Dengan sistem GPS akan diperoleh data garis lintang, serta garis bujur dari GPS receiver.  Data tersebut akan diteruskan oleh mikrokontroler untuk ...

Penentuan Koordinat Titik pada Teknologi Garis dalam Grafika Komputer dengan Menggunakan Algoritma Line Equation

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Mufadhol Mufadhol

2014-07-01

Full Text Available Grafika  Komputer atau  computer graphics  adalah  bagian  dari ilmu  komputer yang  berkaitan  dengan pembuatan  dan  manipulasi gambar  (visual  secara  digital.  Bentuk sederhana  dari grafika  komputer adalah grafika  komputer 2D yang  kemudian  berkembang  menjadi grafika  komputer 3D.  Pola  penggambaran  yang paling sederhana adalah dengan menggunakan titik pada teknologi garis. Algoritma Line Equation merupakan salah satu metode untuk menentukan lokasi koordinat titik pada teknologi garis dalam grafika komputer dengan cara menentukan nilai gradien garis serta garis yang berpotongan dengan sumbu Y, sehingga bisa mengetahui pixel yang akan menyala pada screen coordinate

Moving mesh finite element method for finite time extinction of distributed parameter systems with positive exponential feedback; Lokakarya Komputasi dalam Sains dan Teknologi Nuklir VI

Energy Technology Data Exchange (ETDEWEB)

Garnadi, A D [Department of Matematics, Bogor Institute of Agriculture, Bogor (Indonesia)

1997-07-01

In the distributed parameter systems with exponential feedback, non-global existence of solution is not always exist. For some positive initial values, there exist finite time T such that the solution goes to infinity, i.e. finite time extinction or blow-up. Here is present a numerical solution using Moving Mesh Finite Element to solve the distributed parameter systems with exponential feedback close to blow-up time. The numerical behavior of the mesh close to the time of extinction is the prime interest in this study.

SISTEM INVENTORI BARANG DENGAN TEKNOLOGI AJAX

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Anna Fitriya

2015-11-01

Full Text Available ABSTRAK Sistem inventori barang pada pertokoan telah banyak dikembangkan untuk meningkatkan efektivitas dan efisiensi. Pada Toko Karya Indah, kegiatan yang berkaitan dengan inventori barang masih dilakukan secara manual sehingga pihak toko kesulitan untuk mengetahui data barang yang masih tersedia, habis, atau hampir habis. Selain itu, proses yang dilakukan membutuhkan waktu yang relatif lama. Oleh karena itu, diperlukan sistem inventori barang. Sistem dibangun dengan bahasa pemrograman PHP dan database MySQL. Sistem disertai teknologi AJAX (Asynchronous JavaScript And XML, khususnya AJAX autocomplete dan AJAX validasi. Hasil yang diperoleh adalah pengolahan data pada sistem inventori barang dengan menggunakan AJAX dapat dilakukan dengan lebih cepat dari pada tanpa AJAX. Kata kunci: sistem inventori, AJAX.

ANALISA SUMBER DAYA MANUSIA TEKNOLOGI INFORMASI MENGGUNAKAN KERANGKA KERJA COBIT 4.1” (STUDI KASUS : UNIT PELAKSANA TEKNIS TELEMATIKA UNIVERSITAS PEMBANGUNAN NASIONAL “VETERAN” JAWA TIMUR

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Mohammad Idhom

2016-08-01

Full Text Available Pengelolaan sumber daya manusia merupakan proses dan struktur hubungan yang mengendalikan dan mengarahkan suatu organisasi perusahaan dalam mencapai tujuan organisasi dengan menambahkan nilai agar teknologi informasi dan prosesnya dapat diseimbangkan dengan resikonya. Diperlukan sebuah evaluasi sumber daya manusia dibidang teknologi informasi untuk mengetahui sejauh mana tingkatan pengelolaan terhadap sumber daya manusia di Unit Pelaksana Teknis Telematika saat ini. Sumber daya manusia di bidang teknologi informasi pada Unit Pelaksana Teknis Telematika membutuhkan pengembangan dan pengelolaan sesuai dengan harapan organisasi. Melihat terbatasnya sumber daya manusia di bidang teknologi informasi pada Unit Pelaksana Teknis Telematika sangat terbatas sehingga kegiatan operasional masih belum efektif dan memenuhi sasaran yang diharapkan. Melihat kondisi organisasi yang mengalami terbatas pada sumber daya manusia di bidang teknologi informasi dilakukan evaluasi secara detail dengan menggunakan COBIT 4.1.Dalam melakukan evaluasi sumber daya manusia dengan menggunakan kerangka kerja COBIT  yang berfokus pada Domain PO7 diharapkan dapat memberikan acuan dan perbaikan yang lebih efektif terhadap organisasi ke depannya.

Analisis Kelayakan Implementasi Teknologi LTE 1.8 GHz Bagi Operator Seluler di Indonesia [Feasibility Analysis of LTE 1.8 GHz for Mobile Operators in Indonesia

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Sri Ariyanti

2015-06-01

Full Text Available Peningkatan kebutuhan layanan data mendorong operator telekomunikasi berusaha mengimplementasikan jaringan akses broadband yang lebih handal.  Teknologi LTE merupakan salah satu teknologi dengan kecepatan mencapai tiga kali dibanding teknologi HSDPA, sehingga diharapkan dapat memenuhi kebutuhan pelanggan data mobile. Refarming frekuensi 1.8 GHz  untuk penerapan teknologi LTE memberikan efisiensi karena tidak perlu membayar BHP lagi untuk menyewa frekuensi baru. Teknologi 2G GSM selama ini juga semakin ditinggalkan, masyarakat di daerah perkotaan cenderung lebih banyak menggunakan layanan data.  Sebelum diterapkannya teknologi LTE pada frekuensi 1.8 GHz perlu adanya kajian untuk mengetahui kelayakan teknologi LTE pada frekuensi 1.8 GHz. Penelitian ini bertujuan untuk melakukan cost-benefit analysis implementasi LTE pada frekuensi 1.8 GHz.  Metode penelitian menggunakan pendekatan kualitataif yang didukung dengan data kuantitatif.  Hasil penelitian menunjukkan bahwa minimal bandiwdth yang diperlukan agar implementasi LTE layak digunakan adalah 15 MHz.  Meskipun tanpa Global Frequency Returning, penggunaan bandwidth 10 MHz tidak layak digunakan untuk implementasi LTE.      *****The incresing of data demand drives mobile operators to implement more reliable broadband access network. LTE technology has downlink peak rate up to three times than HSDPA,  hence it may fulfill the mobile data user requirement. Frequency 1.8 GHz refarming can be implemented to provide efficiency because They do not need to pay licence fee for leasing new frequency. GSM technology will be abandoned since it is not growing anymore. Besides that, dense urban users tend to use data mobile.  Before implementing LTE technology  on 1.8 GHz frequency, It is necessary to analysis the feasibility such technology. This research used qualitative method supported by quantitative  approach.  The result of this research showed that minimum bandwidth to implement 1.8 GHz LTE

The modal transfer analysis by adding transport costs. Case study: The use of bus and private vehicle student Institut Teknologi Sumatera

Science.gov (United States)

Muliarto, H.; Alhamidi; Syahbandi, M.

2017-06-01

Since the last two years the Institut Teknologi Sumatera to accept new students in large numbers. Increasing the number of students is directly proportional to the increase of private vehicles that enter the campus it is not in line with the policy of the Institut Teknologi Sumatera as Smart, Friendly, and Forest Campus. Institut Teknologi Sumatera as Smart, Friendly, and Forest Campus fact has made some deal with mass public transport, Damri, to provide bus transportation to the Institut Teknologi Sumatera, but the number of bus users is still inferior to the number of private vehicle users. This study was conducted to see the modal transfer of the entire academic community ITERA, from private cars to public transport such as buses, with the addition of transportation costs in the form of parking rates. This study shows the dominant displacement can occur if the respondent charged parking fees of IDR 4.000. Besides the displacement mode of transportation from using private vehicles be using the bus can occur if Trans Lampung fix three systems including bus departure and arrival schedules, facility service providers that support, and the addition of the Bus Trans Lampung.

PENGARUH TEKNOLOGI INFORMASI, SALING KETERGANTUNGAN, KARAKTERISTIK SISTEM AKUNTANSI MANAJEMEN TERHADAP KINERJA MANAJERIAL

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Arsono Laksmana

2002-01-01

Full Text Available The understanding of the antecedent conditions influencing the design of management accounting systems (MAS is very limited. Recently, researchers focus their attention on the understanding how different contingency variables influence MAS. The results of these studies have been, at best, equivocal and numerous calls have been made for further research.This study examines the role of management accounting system characteristics on the relationship to information technology, interdependence and managerial performance. Management accounting system characteristics was defined to the extent on which managers use broad scope MAS information for managerial decision making. Hypotheses were generated for indirect effects of contingency variables. The responses of 110 managers, drawn from manufacturing companies in East Java, were analyzed using a structural equation modelling (SEM. The results indicate that management accounting system characteristics act as a mediator in the relationship between information technology, organizational interdependence and managerial performance. Abstract in Bahasa Indonesia : Penelitian tentang faktor-faktor yang mempengaruhi rancangan sistem akuntansi manajemen (SAM masih sangat terbatas. Akhir-akhir ini perhatian peneliti telah dicurahkan untuk memahami bagaimana variabel kontinjensi yang berbeda mempengaruhi SAM. Banyak penelitian yang telah dilakukan menunjukkan hasil yang tidak konsisten, karenanya diperlukan penelitian-penelitian lanjutan. Penelitian ini mengkaji peran karakterisrik sistem akuntansi manajemen terhadap hubungan antara teknologi informasi, saling ketergantungan dan kinerja manajerial. Karakteristik SAM didefinisikan sebagai tingkat dimana manajer menggunakan informasi SAM scope untuk pengambilan keputusan manajerial. Respon yang diperoleh dari 110 manajer yang bekerja pada perusahaan industri manufaktur di Jawa Timur dianalisa dengan menggunakan structural equation modelling (SEM. Hasil penelitian

ANALISIS KEPERCAYAAN-KEPERCAYAAN INDIVIDU DALAM MENGGUNAKAN TEKNOLOGI INFORMASI DALAM MENUNJANG PROSES BELAJAR MENGAJAR DI PERGURUAN TINGGI

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Supardi Supardi

2017-04-01

Full Text Available Penelitian ini bertujuan untuk mendiskusikan dan menguji secara empiris hubungan faktor sosial dengan cognitive absorption dan hubungannya terhadap faktor kepercayaan-kepercayaan (perceived ease of use dan perceived usefulness dalam menggunakan teknologi informasi pada proses belajar mengajar diperguruan tinggi. Penelitian ini menggunakan sebanyak 125 dosen jurusan akuntansi di propinsi Yogyakarta sebagai responden. Faktor sosial diukur dengan menggunakan pengaruh rekan sejawat, cognitive absorption diukur dengan menggunakan lima dimensi yaitu temporal dissociation, focused immertion, heightened enjoyment, control, dan curiosity serta kepercayaan-kepercayaan diukur dengan menggunakan perceived ease of use dan perceived usefulness. Metode pengambilan sampel yang digunakan dalam penelitian ini adalah secara non-probability yaitu purposive sampling dengan tipe judgment. Data dianalisis dengan structural equation modeling (SEM menggunakan SmartPLS2.0. Dari hasil pengujian hipotesis, diperoleh temuan bahwa seluruh hipotesis terdukung. Hal ini ditunjukkan dengan adanya bukti hubungan secara positif signifikan antara faktor sosial dengan cognitive absorption dan cognitive absorption dengan faktor kepercayaan-kepercayaan dalam menggunakan teknologi informasi. Penelitian ini telah membuktikan adanya pengaruh faktor sosial terhadap cognitive absorption dalam kepercayaan-kepercayaan menggunakan teknologi infomarmasi untuk mendukung proses belajar mengajar. Selain itu, penelitian ini telah berhasil mengembangkan model penelitian yang dilakaukan oleh Agarwal dan Karahanna (2000, yaitu dengan memberikan bukti empiris faktor sosial sebagai anteseden bagi cognitive absorption

Hubungan Multitasking Teknologi Informasi terhadap Produktivitas Kerja (Studi Kasus: Mahasiswa ITS)

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Marendha, Galang Arga; Susanto, Tony Dwi; Arifiana, Isrida Yul

2016-01-01

Pada era globalisasi saat ini cara hidup individu umumnya para remaja dan dewasa yang selalu bergerak cepat dalam mendapatkan informasi terbaru agar tidak tertinggal dari yang lain memungkinkan melakukan pekerjaan secara bersamaan. Mayoritas dari individu-individu menganggap melakukan banyak pekerjaan sekaligus dapat digunakan sebagai solusi yang tepat. Dengan kemajuan teknologi saat ini dan perilaku seperti itu, banyak sekali contoh pekerjaan yang dilakukan secara bersama-sama seperti halnya...

Identifikasi dan Tingkat Penerapan Inovasi Teknologi Padi Sawah di Kabupaten Parigi Moutong Sulawesi Tengah

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Syafruddin Syafruddin

2016-07-01

Full Text Available Pencapaian tingkat swasembada dan ketahanan pangan khususnya beras tidak terlepas dari beberapa dukungan seperti sumberdaya alam dan penerapan inovasi teknologi. Kabupaten Parigi Moutong merupakan salah satu wilayah penghasil beras yang cukup besar di Sulawesi Tengah yang diharapkan dapat menjadi sumber pertumbuhan baru produksi beras Nasional di Indonesia. Pemerintah Daerah menetapkan wilayah ini, sebagai daerah penyangga beras terbesar di Sulawesi Tengah. Tujuan dari Penelitian ini adalah untuk : 1. Mengidentifikasi berbagai permasalahan dan tingkat penerapan inovasi teknologi pertanian di Kabupaten Parigi Moutong dan 2. Menetapkan arahan dan alternatif teknologi yang potensial untuk pengembangan lahan di Kabupaten Parigi Moutong. Penelitian ini dilaksanakan sebanyak dua tahap yaitu tahap 1 Desk study dan 2. Penelitian Lapangan. Desk study dilakukan dengan cara penelusuran pustaka dan diskusi dengan stake holders lainnya. Untuk Penelitian lapangan dilaksanakan dengan menggunakan metode survey dengan melakukan pengamatan kondisi sosial ekonomi dan budaya serta pengamatan tingkat penerapan inovasi teknologi melalui pendekatan Partisifatif Rural Aprasial atau Pengenalan Desa Secara Partisifatif (PRA. Pelaksanaan penelitian dilakukan selama 2 bulan yaitu dari bulan Juni hingga bulan Juli 2014. Hasil penelitian menunjukkan bahwa terdapat potensi perluasan areal persawahan dan peningkatan luas tanam karena didukung oleh iklim dan irigasi yang cukup baik. Tingkat penerapan teknologi masih cukup rendah terutama penggunaan varietas unggul, benih unggul dan bermutu serta pemupukan. The achievement level of self-sufficiency and food security, particularly in rice production should be supported by natural resources and the application of technology innovation.  Parigi Moutong Regency is one of the largest rice producer areas in Central Sulawesi, which is expected to be a new growth source area of national rice production in Indonesia. Local government

TEKNOLOGI BIOMETRIK DENGAN METODE SIDIK JARI UNTUK SISTEM KEAMANAN DATABASE

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Adhi Kusmantoro

2006-07-01

Full Text Available Keamanan dalam teknologi dunia maya pada saat sangat diperlukan mengingat banyaknya masyarakat yang telah mengakuiteknologi, sehingga kecenderungan banyak ingin mengetahui atau bahkan mencuri sesuatu rahasia super yang sifatnya atau hak cipta yang di bawah aeigis hukum untuk mencari keuntungan individu dengan crack atau lebih dikenal dengan hacker.

Pengembangan Teknologi Informasi Mobile Learning Fakultas Teknik Universitas Diponegoro Berbasis Android

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Resi Jiwa Kasatria

2014-11-01

Full Text Available Perkembangan teknologi mobile seluler sudah sedemikian cepat dan dapat dirasakan di seluruh dunia dan dimanfaatkan dalam berbagai bidang kehidupan. Perkembangan ini dapat pula dilakukan dalam dunia pendidikan dan memungkinkan terobosan baru dalam belajar secara mobile menggunakan perangkat teknologi informasi (handphone atau disebut mobile learning (m-learning. M-learning memiliki beberapa kelebihan di antaranya adalah independensi dalam pembelajaran. Namun, di sisi lain, perangkat pembelajaran m-learning memiliki keterbatasan sumber daya dan keragaman platform sehingga diperlukan rancangan yang mampu menjamin kompatibilitas. Aplikasi Mobile Learning ini dikembangkan menggunakan Java EE untuk menangani servernya dan untuk sisi klien menggunakan Bootstrap mobile. Basis data yang digunakan adalah MySQL. Aplikasi ini akan mempunyai 3 role pengguna yaitu admin yang akan menangani penambahan user dan pengelolaan mata kuliah, dosen yang akan memberikan materi, tugas dan kuis dan mahasiswa yang dapat melihat materi, tugas dan kuis yang diberikan dosen. Mobile Learning ini dapat membantu dosen dan mahasiswa dalam melakukan interaksi dalam berbagi materi, dalam pemberian tugas dan mengerjakan kuis. Mahasiswa maupun dosen tidak lagi harus bertatap muka, yang diperlukan hanyalah koneksi internet untuk melakukan proses belajar mengajar. Selain itu Mobile Learning ini juga dapat berjalan dengan baik saat diuji pada 3 buah versi android yang berbeda yaitu versi 2.3, versi 4.0 dan versi 4.2.

Pengembangan Peta Interaktif Tiga Dimensi Perpustakaan Pusat Institut Teknologi Sepuluh Nopember Menggunakan Unreal Engine

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Mazza Fitroni

2015-03-01

Full Text Available Teknologi yang semakin berkembang pesat saat ini membuat penyampaian informasi kepada masyarakat sangat cepat dan banyak perubahan terutama mengenai bangunan. Dahulu penyampaian informasi mengenai bangunan hanya menggunakan dua dimensi (2D, namun sekarang dapat menggunakan tiga dimensi (3D. Tampilan informasi bangunan gambar 3D ini menjadi terlihat lebih jelas, menarik, dan detail. Tak terkecuali pada perguruan tinggi Intstitut Teknologi Sepuluh Nopember (ITS menjadi objek visualisasi 3D sebagai sarana promosi terhadap konsumen atau calon mahasiswa baru. Pada paper ini akan berisi tentang aplikasi virtual peta 3D yang akan menampilkan objek sebuah gedung Perpustakaan Pusat ITS. Aplikasi yang nanti akan digunakan dalam pembuatan virtual 3D adalah dengan Unreal Engine, dan adobe Flash sebagai user interface untuk informasi dan interaksi didalamnya. Aplikasi pendukung utama yaitu 3Ds Max untuk modelling benda 3D. Aplikasi virtual peta 3D nantinya akan menyampaikan tampilan sebuah Gedung Perpustakaan Pusat ITS yang memudahkan pengguna / user untuk mengetahui dan mengunjungi gedung tersebut secara virtual seperti dunia nyata

Teknologi og forskningslære i videregående skole: Hvem er lærerne og hvordan former de faget?

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Berit Bungum

2009-05-01

Full Text Available Teknologi og forskningslære er et nytt og mangfoldig programfag i videregående skole. Denne artikkelen presenterer en undersøkelse av lærerne i dette faget: hva slags bakgrunn de har, hva de ser som sine styrker og utfordringer i å undervise faget, og hvordan de med utgangspunkt i sin kompetanse realiserer ideene bak læreplanen. Undersøkelsen er utført som en skriftlig spørreundersøkelse med utdypende intervjuer med utvalgte lærere. Resultatene viser at lærerne som har deltatt i undersøkelsen samlet sett er en svært kompetent gruppe, men at de i stor grad framtrer som enten "teknolog" eller "forsker" i hva de ser som sine styrker og utfordringer i faget. Videre beskrives hvordan to lærere, som representerer arketyper av lærere i disse to gruppene, tolker læreplanen ulikt i lys av sin egen kompetanse, og hvordan de på ulike måter realiserer innholdet i Teknologi og forskningslære som fag ved sine skoler.

Peningkatan Kesejahteraan Perajin Batik Tulis Melalui Penerapan Teknologi Pemungutan Zat Warna Alam

OpenAIRE

Prima Astuti Handayani; Catur Rini Widyastuti; Adhi Setiawan

2013-01-01

Seiring kemajuan teknologi zat warna alam tergeser oleh keberadaan zat warna sintetis. Penggunaan zat warna alam masih tetap dijaga keberadaannya khususnya pada pembatikan. Kain batik yang menggunakan zat warna alam memiliki nilai jual yang tinggi karena memiliki nilai seni dan warna khas, tidak bersifat karsiogenik, ramah lingkungan serta berkesan etnik dan eksklusif. Zat warna alam coklat untuk pewarnaan batik dapat diperoleh dari kulit soga tingi melalui proses ekstraksi dengan pelarut eta...

Teknologi Pengendalian Gulma Alang-alang dengan Tanaman Legum untuk Pertanian Tanaman Pangan

OpenAIRE

Ishak Juarsah

2015-01-01

Di Indonesia, Alang-alang (Imperata cylindrica L. Beauv) merupakan salah satu gulma terpenting dan termasuk sepuluh gulma bermasalah di dunia.  Melalui biji dan rimpang, alang-alang dapat tumbuh dan menyebar luas pada hampir semua kondisi lahan. Teknologi pengendalian alang-alang telah banyak dikenal namun belum dapat menjamin eradikasi populasi alang-alang secara berkelanjutan tanpa diikuti oleh kultur teknis dan pola budidaya tanaman pangan sepanjang tahun. Hasil penelitian menunjukan bahwa...

Evaluasi Soft Skills dalam Pembelajaran Mahasiswa Baru di Fakultas Teknologi Pertanian Universitas Udayana

OpenAIRE

Arnata, I Wayan; Surjoseputro, Sutarjo

2014-01-01

: Penelitian ini dilakukan dengan tujuan untuk mengevaluasi atribut soft skills yang dimiliki oleh mahasiswa baru Fakultas Teknologi Pertanian Universitas Udayana. Penelitian dilakukan dengan menggunakan desain pretest-posttest menggunakan kuesioner yang berisi atribut-atribut soft skills dan penilaian kemampuan pribadi. Dari hasil evaluasi terhadap pengembangan atribut soft skills diperoleh bahwa kemampuan soft skills yang dimiliki oleh mahasiswa baru setelah mengikuti pelatihan semuanya men...

Integrasi Arsitektur Dan Manajemen Layanan Ti Untuk Pencapaian Fleksibilitas Teknologi Informasi Pada Organisasi

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Aradea, Aradea

2011-01-01

Peran teknologi Informasi (TI) dalam organisasi saat ini telah mengalami pergeseran paradigma, pada awalnyaTI hanya berfokus pada otomatisasi data, pengolahan data atau manipulasi data, saat ini sudah bergeser padafungsi strategi dan layanan. Kesesuaian dan performa layanan TI dapat menjadi faktor penentu dalampencapaian tujuan dan sasaran organisasi, apabila diposisikan dan difungsikan secara tepat dan selarasdengan visi bisnis organisasi. Hal ini tentu dilakukan dengan sudut pandang yang me...

INTEGRASI ARSITEKTUR DAN MANAJEMEN LAYANAN TI UNTUK PENCAPAIAN FLEKSIBILITAS TEKNOLOGI INFORMASI PADA ORGANISASI

OpenAIRE

Aradea, Aradea

2012-01-01

Peran teknologi Informasi (TI) dalam organisasi saat ini telah mengalami pergeseran paradigma, pada awalnyaTI hanya berfokus pada otomatisasi data, pengolahan data atau manipulasi data, saat ini sudah bergeser padafungsi strategi dan layanan. Kesesuaian dan performa layanan TI dapat menjadi faktor penentu dalampencapaian tujuan dan sasaran organisasi, apabila diposisikan dan difungsikan secara tepat dan selarasdengan visi bisnis organisasi. Hal ini tentu dilakukan dengan sudut pandang yang me...

Analisis Quality of Service (QoS Jaringan Telekomunikasi High-Speed Downlink Packet Access (HSDPA pada Teknologi 3.5G

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Mey Fenny Wati Simanjuntak

2016-01-01

Full Text Available Sejak layanan teknologi 3G pertama kali diperkenalkan, permintaan akan layanan berbasis paket data dari tahun ke tahun mengalami peningkatan yang pesat. Menanggapi hal tersebut, para penyedian jaringan telekomunikasi terus berusaha untuk meningkatkan kemampuan jaringannya. Salah satu solusinya menerapkan teknologi High-Speed Downlink Packet Access yang direkomendasikan oleh 3GPP Release 5. Penelitian ini dikhususkan untuk menganalisis Quality of Service jaringan telekomunikasi High-Speed Downlink Packet Access di Kecamatan Tembalang Kota Semarang. Analisis Quality of Service jaringan telekomunikasi High-Speed Downlink Packet Access pada penelitian ini bertujuan untuk memberikan gambaran kualitas jaringan telekomunikasi High-Speed Downlink Packet Access dari sisi bandwidth, throughput, packet loss dan delay. Metode penelitian yang dibahas dalam penelitian ini yaitu penelitian kualitatif observatif, dimana akan dilakukan pengamatan tentang bagaimana QoS jaringan telekomunikasi High-Speed Downlink Packet Access pada teknologi 3.5G di Kecamatan Tembalang Kota Semarang. Proses pengamatan dalam menganalisis Quality of Service jaringan telekomunikasi High-Speed Downlink Packet Access di Kecamatan Tembalang Kota Semarang berdasarkan 4 parameter diantaranya bandwidth, throughput, packet loss dan delay. Aplikasi yang digunakan yaitu monitoring application Elnus Bandwidth Meter dan Axence NetTools Professional 4.0. Selain itu, Quality of Service jaringan telekomunikasi High- Speed Downlink Packet Access di Kecamatan Tembalang Kota Semarang diamati berdasarkan waktu yaitu harian, mingguan dan bulanan.

Beban Biaya Telekomunikasi yang Dikeluarkan Masyarakat Pengaruh dari Adopsi Teknologi [Telecommunication Costs Incurred Expenses Society Effect of Technology Adoption

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Sri Ariyanti

2016-07-01

Full Text Available Salah satu Rencana Pita Lebar Indonesiatahun 2014 – 2019 yaitu dapat memberikan akses bergerak  di wilayah pedesaan  menjangkau 52% pupulasi dengan data rate mencapai 1 Mbps.  Agar layanan pita lebar dapat terjangkau oleh masyarakat luas, maka harga layanan pita lebar ditargetkan paling tinggi sebesar 5% dari rata-rata pendapatan bulanan pada akhir tahun 2019.  Rencana pita lebar dengan target minimal data rate tersebut tidak akan tercapai tanpa adanya perubahan teknologi.  Teknologi yang mendukung terpenuhinya data rate tersebut antara lain teknologi 3.5G dan 4G LTE.  Dalam rangka upgrade teknologi, perlu adanya biaya yang cukup besar yang dikeluarkan oleh operator.  Biaya tersebut sangat mempengaruhi besar biaya yang akan dibebankan kepada pelanggan.  Oleh karena itu dalam penelitian ini mengkaji seberapa besar biaya yang ditanggung pelanggan seluler setelah adanya teknologi baru. Penelitian ini bertujuan untuk mengetahui apakah biaya yang dibebankan kepada masyarakat sudah sesuai dengan yang ditetapkan oleh pemerintah dalam Rencana Pita Lebar Indonesia. Teknik peneltiian ini menggunakan pendekatan data kuantitatif yang dianalisis dengan ekonometrika.  Hasil penelitian menunjukkan bahwa berdasarkan data penegeluarna telekomunikasi rumah tangga maupun data ARPU, biaya yang dibebankan kepada pelanggan sudah memenuhih persyaratan yang telah ditetapaka oleh rencana pita lebar Indonesia yaitu kurang dari 5%. *****One of the Indonesia Broadband Plan in 2014 – 2019 is that it can be provided mobile data reaching 52% rural areas with data rate up to 1 Mbps. In order to be affordable, so that maximum price is 5% of the average monthly income at the end of 2019.  That data rate cannot be achieved without upgrading the technology. The technology of 3.5G and 4G are among others technology that can support high data rate.  In order to upgrade technology, it needs a considerable cost from mobile operators, while it can influence the cost

Safety aspects of using Ag-In-Cd absorber made by PT. Batan Teknologi (Persero) in the core of multi purposes reactor G.A. Siwabessy

International Nuclear Information System (INIS)

Anggoro Septilarso; Zulkarnain; Heryudo Kusumo

2011-01-01

Safety Evaluation has been carried out for the using of Ag-In-Cd Absorber made by PT. Batan Teknologi (Persero) in the core of Multi Purposes Reactor G.A. Siwabessy (RSG-GAS). PT. Batan Teknologi (Persero) only licensed by NUKEM GmbH to produce Fuel Element and Control Element U-Al, U 3 O 8 -Al dan U 3 Si 2 -Al, and not including to produce Ag-In-Cd Absorber. But, BAPETEN evaluator think that the danger would be greater if RSG-GAS use the older absorber than use Ag-In-Cd Absorber made by PT. Batan Teknologi. For this purposes, BAPETEN set some requirements and acceptance criteria to be met by the absorber, that is cold test, hot test, shutdown margin value, control rod drop test and visual test. The test show that Ag-In-Cd Absorber meets all the requirements and acceptance criteria required by BAPETEN. (author)

IMPLEMENTASI KOMPUTASI AWAN MENGGUNAKAN TEKNOLOGI GOOGLE APP ENGINE (GAE DAN AMAZON WEB SERVICES (AWS

Directory of Open Access Journals (Sweden)

Adi Nugroho

2013-04-01

Full Text Available Interoperabilitas, dalam arti cara bagaimana suatu sistem yang memiliki platform perangkat keras dan perangkat lunak tertentu dapat berkomunikasi dengan sistem-sistem yang memiliki platform yang berbeda, mungkin merupakan bagian dari ‘masa lalu’. Di masa-masa yang akan datang, interoperabilitas yang selama ini ditangani secara manual oleh organisasi-organisasi/perusahaan-perusahaan akan ditangani langsung oleh vendor-vendor penyedia komputasi awan (cloud computing yang memang memiliki sumberdaya-sumberdaya manusia (analis sistem, pemrogram, pakar jaringan, perangkat keras (komputer-komputer server yang berjumlah sangat banyak dan berkemampuan raksasa, serta perangkat lunak (sistem operasi, server aplikasi, server Web yang memang memenuhi syarat untuk itu. Di masa yang akan datang, untuk mendapatkan layanan-layanan  (service dan tempat penyimpanan tertentu, organisasi-organisasi/ perusahaan-perusahaan tidak perlu berinvestasi terlalu tinggi untuk menyediakannya sendiri; mereka bisa saja menyewanya dari vendor-vendor komputasi awan yang saat ini mulai bermunculan. Google dan Amazon adalah para pendahulu dari teknologi komputasi awan (cloud computing ini. Melalui tulisan ini, kita tidak akan membahas struktur internal keduanya secara rinci, melainkan kita akan mencoba membahas kelebihan serta kekurangan kedua vendor komputasi awan ini dari sudutpandang para manajer di bidang Teknologi Informasi yang akan melakukan investasi yang bermanfaat bagi organisasi/perusahaannya.

IMPLEMENTASI KOMPUTASI AWAN MENGGUNAKAN TEKNOLOGI GOOGLE APP ENGINE (GAE DAN AMAZON WEB SERVICES (AWS

Directory of Open Access Journals (Sweden)

Adi Nugroho

2012-01-01

Full Text Available Interoperabilitas, dalam arti cara bagaimana suatu sistem yang memiliki platform perangkat keras dan perangkat lunak tertentu dapat berkomunikasi dengan sistem-sistem yang memiliki platform yang berbeda, mungkin merupakan bagian dari masa lalu. Di masa-masa yang akan datang, interoperabilitas yang selama ini ditangani secara manual oleh organisasi-organisasi/perusahaan-perusahaan akan ditangani langsung oleh vendor-vendor penyedia komputasi awan (cloud computing yang memang memiliki sumberdaya-sumberdaya manusia (analis sistem, pemrogram, pakar jaringan, perangkat keras (komputer-komputer server yang berjumlah sangat banyak dan berkemampuan raksasa, serta perangkat lunak (sistem operasi, server aplikasi, server Web yang memang memenuhi syarat untuk itu. Di masa yang akan datang, untuk mendapatkan layanan-layanan (service dan tempat penyimpanan tertentu, organisasi-organisasi/ perusahaan-perusahaan tidak perlu berinvestasi terlalu tinggi untuk menyediakannya sendiri; mereka bisa saja menyewanya dari vendor-vendor komputasi awan yang saat ini mulai bermunculan. Google dan Amazon adalah para pendahulu dari teknologi komputasi awan (cloud computing ini. Melalui tulisan ini, kita tidak akan membahas struktur internal keduanya secara rinci, melainkan kita akan mencoba membahas kelebihan serta kekurangan kedua vendor komputasi awan ini dari sudutpandang para manajer di bidang Teknologi Informasi yang akan melakukan investasi yang bermanfaat bagi organisasi/perusahaannya.

Inovasi Desain, Teknologi, dan Pemasaran Lewat Website Usaha Kecil Menengah Batik dan Lutik (Lurik Batik di Kecamatan Laweyan Surakarta

Directory of Open Access Journals (Sweden)

Anastasia Riani Suprapti

2016-12-01

  Tujuan penelitian terapan ini adalah untuk meningkatkan produktivitas dan mengembangkan produk batik dan lutik yang ada di wilayah Kecamatan Laweyan Surakarta dengan inovasi desain dan teknologi baru. Program ini bekerja sama dengan mitra UKM Batik Dewi (UKM 1 dan Batik Sinung Rejeki (UKM2 yang terletak di Kecamatan Laweyan. Pengusaha batik Laweyan dengan produknya berupa batik dan tekstil bermotif batik (printing dan cap dalam era globalisasi sekarang ini ternyata memiliki daya tahan yang baik, ditengah persaingan dengan produk sejenis dari daerah lain maupun dari luar negeri. Secara garis besar pola yang digunakan dalam implementasi penelitian ini meliputi: diskusi (FGD, kerja bengkel, operasional pabrik, pelatihan dan pendampingan (kelompok dan individu. Seperti halnya Usaha Kecil Menengah pada umumnya, pengusaha batik di Laweyan juga menghadapi masalah Internal meliputi  permodalan, inovasi desain, pemasaran, dan manajemen keuangan, yang meliputi administrasi keuangan/pembukuan. Beberapa solusi yang ditawarkan untuk mengatasi permasalahan yang dihadapi diantaranya adalah melakukan Inovasi desain dan teknologi, pengaturan layout pabrik, dan pemasaran lewat web. Selain itu mengembangkan desain motif batik yang lebih diminati pasar diberikan juga untuk pengembangan teknik kombinasi batik-lurik ikat dengan cara lukis dan pengelantangan. Penggunaan media teknologi informasi dan komunikasi untuk promosi lewat website. Adapun untuk usaha pengembangan manajemen pemasaran,  diusahakan media promosi dan menjalin kerjasama pemasaran  dengan instansi terkait, misalnya dengan mengikuti pameran-pameran di Solo dan Jakarta.

Udvikling af en internetsøgestrategi til identifikation af ny medicinsk teknologi inden for prostatacancer

DEFF Research Database (Denmark)

Thygesen, Marianne; Vondeling, Hindrik; Douw, Karla

2007-01-01

internetsider efter efficiens. Her er efficiens forstået som mindst antal minutter brugt pr. fund af information om en ny væsentlig medicinsk teknologi. Resultater: Strategien består af ti sider, som bør benyttes i følgende rækkefølge: YahooHealth, DoctorsGuide, The National Electronic Library for Medicines...

Perencanaan Tata Kelola Teknologi Informasi Berdasarkan Framework CobiT (Studi Kasus Pada Direktorat Metrologi)

OpenAIRE

Falahah, Falahah

2006-01-01

Tatakelola Teknologi Informasi (TI) merupakan salah satu aspek penting dari tatakelola Perusahaan secara keseluruhan. Pengelolaan TI yang baik akan menjamin efisiensi dan pencapaian kualitas layanan yang baik bagi tujuan bisnis Perusahaan. Penerapan tata kelola ini harus direncanakan dengan baik agar dapat diimplementasikan sesuai dengan kondisi dan kemampuan Perusahaan.Salah satu kerangka kerja tatakelola TI adalah CobiT. Dalam dokumentasi resminya CobiT juga disertai dengan serangkaian pedo...

PENGARUH KEPERCAYAAN, KOMITMEN, DAN TEKNOLOGI INFORMASI TERHADAP KINERJA RANTAI PASOKAN (STUDI KASUS IKM PENGOLAH BUAH MARKISA DI KOTA MAKASSAR

Directory of Open Access Journals (Sweden)

Musran Munizu

2017-03-01

Full Text Available The effective Supply chain management (SCM has increasingly become an important way to enhance competitive strength as well as business performance. Trust, commitment, and well-integrated supply chain by Information Technology (IT support are important elements to improve supply chain performance. The objectives of this study are to examine and analyze the effects of trust variables on supply chain performance, trust on commitment, commitment on supply chain performance, information technology on supply chain performance, and effects of trust variable on supply chain performance through commitment variable to Small and Medium Industries (SMIs of passion fruit processing in Makassar. This study used a quantitative approach, where the questionnaire as main tools for data collection. Data were analyzed by descriptive analysis and partial least square-path modeling (PLS-PM. Data computation used SmartPLS 2.0 Software. The results show that trust has a significant effect on supply chain performance, and it also has a significant effect on commitment. Furthermore, commitment has a significant effect on supply chain performance, and information technology has a significant effect on supply chain performance. Trust can improve the supply chain performance by commitment indirectly, and it gives smaller effect on supply chain performance directly than indirectly mediated by commitment. Then, supply chain performance is more influenced by information technology rather than trust and commitment. The results of this study may have implications for the important role of management in maintaining trust, commitment and utilizing information technology in the supply chain system.Keywords: trust, commitment, Information technology, supply chain performance, SMIs of passion fruit processingAbstrakPengelolaan rantai pasokan yang efektif telah menjadi cara terbaik untuk meningkatkan daya saing dan kinerja perusahaan. Kepercayaan, komitmen, dan dukungan teknologi

PERAN DUKUNGAN ORGANISASIONAL, KOMPETENSI TEKNOLOGI DAN LINGKUNGAN EKSTERNAL DALAM RANGKA MENDORONG PENGADOPSIAN E-COMMERCE PADA USAHA KECIL MENENGAH

Directory of Open Access Journals (Sweden)

Audita Nuvriasari

2014-07-01

menjadi kendala dan pendorong bagi UKM dalam mengadopsi e-commerce dan untuk mengetahui pengaruh dari dukungan organisasional, kompetensi teknologi dan lingkungan eksternal terhadap pengadopsian e-commerce. Jumlah sampel penelitian sebanyak 34 UKM yang ada di wilayah Moyudan, DIY yang telah menggunakan teknologi informasi (internet dalam kegiatan bisnisnya. Penelitian ini menggunakan metode deskriptif dan inferensial untuk memecahkan permasalahan penelitian. Berdasarkan hasil analisis deskriptif dapat ditunjukkan bahwa tujuan utama UKM menggunakan internet dalam kegiatan bisnisnya adalah untuk pencarian informs bisnis (97,1%. Sedangkan faktor utama yang menjadi penghambat bagi UKM dalam mengadopsi e-commerce adalah keterbatasan kemampuan dan ketermpilan sumber daya manusia dalam penguasaan teknologi informasi (70,6%. Manfaat utama yang diperoleh UKM dengan pengadopsian e-commerce dalam menjalankan kegiatan bisnisnya adalah dapat dengan mudah mengakses informasi bisnis (85,3%. Hasil lain dari penelitian ini menjelaskan bahwa terdapat pengaruh yang positip dan signifikan antara dukungan organisasional, kompetensi teknologi dan lingkungan eksternal terhadap pengadopsian e-commerce. Kata Kunci: e-commerce, dukungan organisasional, kompetensi teknologi, lingkungan eksternal

APLIKASI MOBILE ZAPPELINE SEBAGAI MEDIA TEKNOLOGI MODIFIKASI CUACA (TMC) DAN PENIPISAN POLUTAN UDARA (ASAP)

OpenAIRE

Purwadi, Purwadi; Sunarto, Faisal; Muttaqin, Alfan; Seto, Tri Handoko

2018-01-01

IntisariTelah dilakukan kajian aplikasi mobile zappeline sebagai media teknologi modifikasi cuaca (tmc) dan media penipisan polutan udara (asap) pada sebuah truk Mitsubishi Colt Diesel berukuran 5,960 x 1,970 meter. Dengan kendaraan tersebut, direkomendasikan dimensi zappeline berbentuk bangun ruang eliptical dengan jari-jari diagonal a dan b masing-masing 3,25 dan 0,65 meter. Selanjutnya, karakteristik aerodinamik dan fisika dihitung dengan memecahkan beberapa persamaan fisika secara numerik...

Biomedisinsk teknologi i idrett: Hvor går grensene?

Directory of Open Access Journals (Sweden)

Sigmund Loland

2010-01-01

Full Text Available I denne artikkelen drøfter jeg bruk av biomedisinsk teknologi i prestasjonsfremmende hensikt i konkurranseidrett. Mer presist utforsker jeg mulighetene for å skille mellom etisk akseptabel og etisk uakseptabel bruk. Jeg kritiserer WADAs normative grunnlag for å forby visse biomedisinske midler og metoder, og argumenterer for at eventuelle forbud må bygge på tydeligere verdisyn på idrett. Jeg undersøker to idealtypiske syn og deres teknologiske implikasjoner. Det smale synet er liberalt og avviser begrensninger i bruk av biomedisinske midler og metoder blant voksne idrettsutøvere som dårlig begrunnet paternalisme. Det brede synet innebærer en mer restriktiv holdning og aksepterer en viss regulering av trening og prestasjonsutvikling også utenfor konkurransene. I en avsluttende del veier jeg det smale og det brede synet mot hverandre og reflekterer over hvilket syn som vil dominere framtidens idrett.Nøkkelord: etikk, idrett, biomedisinsk teknologi, dopingEnglish summary: The use of biomedical technology in sport: Are there any limits?In the article I examine the use of biomedical technology to enhance performance in competitive sport. More specifically I examine the possibilities for distinguishing between ethically acceptable and ethically unacceptable use of such technology. I criticize the World Antidoping Agency's (WADA normative criterion for banning certain technologies as it is vague and unclear. I argue that any ban by WADA has to build on a clear and operational normative view of sport. Two relevant ideal-typical views are examined together with their technological implications. The narrow view is liberal and rejects restrictions on the use of biomedical technology among professional athletes as unjustifiable paternalism. The wider view implies a more restrictive approach and accepts certain regulations of performance-enhancing means and methods outside of competitions. In the conclusion, I compare the narrow and the wider

An electrochemical study of U(VI) and Cr(VI) in molten borates

International Nuclear Information System (INIS)

Brigaudeau, M.; Gregori de Pinochet, I. de

1977-01-01

The electrochemical reduction of U(VI) and Cr(VI), in molten Na 2 B 4 O 7 at 800 deg C was studied by means of linear sweep voltammetry, and chronopotentiometry. The reduction of U(VI) to U(V) proceeded reversibly at a platinum electrode. The diffusion coefficient for the U(VI) species at 800 deg C was 4.10 -7 cm 2 .s -1 . The activation energy of diffusion was (34,8 +- 0,8) kcal. mole -1 . Electrochemical studies of Cr(VI) at 800 0 C reveal a two-step reduction process at a platinum electrode. Only the voltammogram for the first step charge transfer process was studied. Analysis indicated that Cr(VI) is reversibly reduced to Cr(III) at a platinum electrode. The diffusion coefficient for Cr(VI) at 800 0 C is 1,9.10 -7 cm 2 .s -1 [fr

TANTANGAN DAKWAH DI ERA TEKNOLOGI DAN INFORMASI: Formulasi Karakteristik, Popularitas, dan Materi di Jalan Dakwah

Directory of Open Access Journals (Sweden)

nur Ahmad

2015-11-01

Full Text Available Teknologi di era globalisasi telah mengalami kemajuan yang begitu pesat. Berbagai macam media komunikasi bersaing dalam memberikan informasi tanpa batas. Fasilitas internet merupakan yang terlengkap dan efisien, dimana segala bentuk dan macam informasi dapat diakses dengan mudah dan murah termasuk dalam hal ini adalah dakwah di era teknologi didukung dengan semakin menjamurnya warung internet yang memasang tarif murah, kemana dan dengan siapapun. Sekarang kita bisa melakukan dakwah dengan mengunakan fasilitas digital, diantaranya bisa melalui radio, televisi, telepon seluler, media internet, facebook, atau twiter. Berdakwah melalui media internet merupakan salah satu media komunikasi yang fenomenal dan canggih yang lahir di era 60-an. Namun, kemajuan teknologi dan informasi, khususnya media televisi, memungkinkan seorang dai untuk berimprovisasi dengan selingan humor dan hal-hal lain, agar materi ceramahnya tetap menarik untuk disimak. Dampaknya, orientasi dakwah yang diperankan para dai, juga semakin berkembang, bahkan cenderung menjadi bias. Pola berdakwah melalui media sebagai wujud kemajuan teknologi menjadi tantangan bagi diri sendiri bagi seseorang dai. Pengaruh media memungkinkan seorang dai memperoleh popularitas di mata pemirsanya seperti layaknya seorang selebriti (publik figur dan tidak menutup kemungkinan pula setiap kegiatan dakwahnya sering dinilai dengan materi. Kata Kunci: Karakteristik, Popularitas, Materi, Tantangan Dakwah. THE CHALLENGES OF DAWA IN THE ERA OF TECHNOLOGY AND INFORMATION: THE FORMULATION CHARACTERISTICS, POPULARITY, AND MATERIAL IN THE PATH OF DAWA. Technology in the era of globalization has experienced a rapid progress. A wide range of communication media compete in providing information without limits. The internet is the most comprehensive and efficient, where all shapes and kinds of information can be accessed easily and inexpensively included in this is the dawa in the era of technology supported by the

ANALISIS KEPERCAYAAN-KEPERCAYAAN INDIVIDU DALAM MENGGUNAKAN TEKNOLOGI INFORMASI DALAM MENUNJANG PROSES BELAJAR MENGAJAR DI PERGURUAN TINGGI

OpenAIRE

Supardi Supardi; Eka Noor Asamara

2017-01-01

Penelitian ini bertujuan untuk mendiskusikan dan menguji secara empiris hubungan faktor sosial dengan cognitive absorption dan hubungannya terhadap faktor kepercayaan-kepercayaan (perceived ease of use dan perceived usefulness) dalam menggunakan teknologi informasi pada proses belajar mengajar diperguruan tinggi. Penelitian ini menggunakan sebanyak 125 dosen jurusan akuntansi di propinsi Yogyakarta sebagai responden. Faktor sosial diukur dengan menggunakan pengaruh rekan sejawat, cognitive ab...

Hvordan kan teknologi skape nye undervisnings- og læringsmåter i fremmedspråksundervisningen fram mot 2030?

Directory of Open Access Journals (Sweden)

Eli-Marie Danbolt Drange

2014-09-01

Full Text Available I denne artikkelen drøfter jeg hvordan teknologi kan skape nye undervisnings- og læringsmåter i fremmedspråksundervisningen fram mot 2030. Jeg starter med å skissere et mulig framtidsscenario i form av et blogginnlegg skrevet av en 15 åring i året 2030. Videre i artikkelen tar jeg utgangspunkt i dette framtidsscenarioet og sammenligner det med dagens situasjon, i tillegg til at jeg drøfter hva som må til for at scenarioet kan oppfylles. Læreren spiller en nøkkelrolle i utviklingen av nye undervisnings- og læringsmåter, og det er først når læreren integrerer teknologien i sin undervisning at nye praksiser oppstår. Jeg viser noen konkrete eksempler på bruk av teknologi på nye måter, samt refleksjon rundt utviklingen framover.

Vi, de civiliserede

DEFF Research Database (Denmark)

Nyemann, Dorthe

2016-01-01

Vi har i årtier troet på, at mennesker under de rette omstændigheder kan lykkes med at leve i fred og fordragelighed med hinanden. Skal vi til at erkende, at også vores samfundsstrukturer kun er en tynd fernis ovenpå et utæmmeligt voldspotentiale og egoisme?......Vi har i årtier troet på, at mennesker under de rette omstændigheder kan lykkes med at leve i fred og fordragelighed med hinanden. Skal vi til at erkende, at også vores samfundsstrukturer kun er en tynd fernis ovenpå et utæmmeligt voldspotentiale og egoisme?...

Studi Kesiapan Pemanfaatan Teknologi Informasi dan Komunikasi Serta Implementasi E-Goverment dengan Kerangka Kerja Cobit

Directory of Open Access Journals (Sweden)

Ahmad Budi Setiawan

2011-03-01

Full Text Available Studi ini bertujuan untuk melihat tentang kesiapan pemanfaatan TeknologiInformasi dan Komunikasi (e-readiness pada Kementerian Komunikasi danInformatika dalam rangka implementasi tata kelola pemerintahan secaraelektronis atau e-government. Dalam studi ini juga dibahas mengenai strategi implementasi e-government menggunakan kerangka kerja COBIT. Hasil dari studi ini menyimpulkan bahwa dengan menggunakan kerangka kerja COBIT sangat membantu dalam menentukan target kinerja proses-proses TI dalam proses implementasi e-government.

Hubungan Beberapa Faktor Sosial Ekonomi Dengan Sikap Petani Cabai Merah Terhadap Teknologi Pembuatan Pupuk Bokashi.

OpenAIRE

Samosir, Lenny Dinamaria

2011-01-01

Pengambilan sampel dalam penelitian ini dilakukan secara kelompok atas dasar kelompok petani peserta pelatihan pembuatan pupuk bokashi dan nonpeserta pelatihan pembuatan pupuk bokashi yang diusahan pada lahan cabai sebanyak 22 sampel. Dari hasil penelitian dapat disimpulkan bahwa: 1. Sikap petani cabai terhadap teknologi pembuatan bokashi di Desa Sondi Raya adalah positif yaitu dari 22 orang petani cabai, 13 orang (59,09 %) memiliki sikap positif dan 9 orang (40,91 %) mem...

Development of Delta Wing Aerodynamics Research in Universiti Teknologi Malaysia Low Speed Wind Tunnel

OpenAIRE

Shabudin Mat; I. S. Ishak; Tholudin Mat Lazim; Shuhaimi Mansor; Mazuriah Said; Abdul Basid Abdul Rahman; Ahmad Shukeri Mohd. Kamaludim; Romain Brossay

2014-01-01

This paper presents wind tunnel experiment on two delta wing configurations which are differentiated by their leading edge profiles: sharp and round-edged wings. The experiments were performed as a part of the delta wing aerodynamics research development in Universiti Teknologi Malaysia, low speed tunnel (UTM-LST). Steady load balance and flow visualization tests were conducted at Reynolds numbers of 0.5, 1, and 1.5 × 106, respectively. The flow measurement at low Reynolds number was also per...

Plutonium(VI) accumulation and reduction by lichen biomass: correlation with U(VI)

International Nuclear Information System (INIS)

Ohnuki, Toshihiko; Aoyagi, Hisao; Kitatsuji, Yoshihiro; Samadfam, Mohammad; Kimura, Yasuhiko; William Purvis, O.

2004-01-01

The uptake of plutonium(VI) and uranium(VI) by lichen biomass was studied in the foliose lichen Parmotrema tinctorum to elucidate the migration behavior of Pu and U in the terrestrial environment. Pu and U uptake by P. tinctorum averaged 0.040±0.010 and 0.055±0.015 g g dry -1 , respectively, after 96 h incubation with 4.0x10 -4 mol l -1 Pu solutions of pH 3, 4 and 5. SEM observations showed that the accumulated Pu is evenly distributed on the upper and lower surfaces of P. tinctorum, in contrast to U(VI), which accumulated in both cortical and medullary layers. UV/VIS absorption spectroscopy demonstrates that a fraction of Pu(VI) in the solution is reduced to Pu(V) by the organic substances released from P. tinctorum, and the accumulated Pu on the surface is reduced to Pu(IV), while U(VI) keeps the oxidation state of VI. Since the solubility of Pu(IV) hydroxides is very low, reduced Pu(VI) does not penetrate to the medullary layers, but is probably precipitated as Pu(IV) hydroxides on the cortical lichen surface. It is concluded that the uptake and reduction of Pu(VI) by lichens is important to determine the mobilization and oxidation states of Pu in the terrestrial environment

Anaerobic bio-removal of uranium (VI) and chromium (VI): Comparison of microbial community structure

International Nuclear Information System (INIS)

Martins, Monica; Faleiro, Maria Leonor; Chaves, Sandra; Tenreiro, Rogerio; Santos, Erika; Costa, Maria Clara

2010-01-01

Several microbial communities, obtained from uranium contaminated and non-contaminated samples, were investigated for their ability to remove uranium (VI) and the cultures capable for this removal were further assessed on their efficiency for chromium (VI) removal. The highest efficiency for removal of both metals was observed on a consortium from a non-contaminated soil collected in Monchique thermal place, which was capable to remove 91% of 22 mg L -1 U(VI) and 99% of 13 mg L -1 Cr(VI). This study revealed that uranium (VI) removing communities have also ability to remove chromium (VI), but when uranium (VI) was replaced by chromium (VI) several differences in the structure of all bacterial communities were observed. TGGE and phylogenetic analysis of 16S rRNA gene showed that the uranium (VI) removing bacterial consortia are mainly composed by members of Rhodocyclaceae family and Clostridium genus. On the other hand, bacteria from Enterobacteriaceae family were detected in the community with ability for chromium (VI) removal. The existence of members of Enterobacteriaceae and Rhodocyclaceae families never reported as chromium or uranium removing bacteria, respectively, is also a relevant finding, encouraging the exploitation of microorganisms with new abilities that can be useful for bioremediation.

Anaerobic bio-removal of uranium (VI) and chromium (VI): Comparison of microbial community structure

Energy Technology Data Exchange (ETDEWEB)

Martins, Monica [Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Faleiro, Maria Leonor [IBB - Centro de Biomedicina Molecular e Estrutural, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Chaves, Sandra; Tenreiro, Rogerio [Universidade de Lisboa, Faculdade de Ciencias, Centro de Biodiversidade, Genomica Integrativa e Funcional (BioFIG), Campus de FCUL, Campo Grande 1749-016 Lisboa (Portugal); Santos, Erika [Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Costa, Maria Clara, E-mail: mcorada@ualg.pt [Centro de Ciencias do Mar, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

2010-04-15

Several microbial communities, obtained from uranium contaminated and non-contaminated samples, were investigated for their ability to remove uranium (VI) and the cultures capable for this removal were further assessed on their efficiency for chromium (VI) removal. The highest efficiency for removal of both metals was observed on a consortium from a non-contaminated soil collected in Monchique thermal place, which was capable to remove 91% of 22 mg L{sup -1} U(VI) and 99% of 13 mg L{sup -1} Cr(VI). This study revealed that uranium (VI) removing communities have also ability to remove chromium (VI), but when uranium (VI) was replaced by chromium (VI) several differences in the structure of all bacterial communities were observed. TGGE and phylogenetic analysis of 16S rRNA gene showed that the uranium (VI) removing bacterial consortia are mainly composed by members of Rhodocyclaceae family and Clostridium genus. On the other hand, bacteria from Enterobacteriaceae family were detected in the community with ability for chromium (VI) removal. The existence of members of Enterobacteriaceae and Rhodocyclaceae families never reported as chromium or uranium removing bacteria, respectively, is also a relevant finding, encouraging the exploitation of microorganisms with new abilities that can be useful for bioremediation.

II-VI semiconductor compounds

CERN Document Server

1993-01-01

For condensed matter physicists and electronic engineers, this volume deals with aspects of II-VI semiconductor compounds. Areas covered include devices and applications of II-VI compounds; Co-based II-IV semi-magnetic semiconductors; and electronic structure of strained II-VI superlattices.

Cinética e equilíbrio de adsorção dos oxiânions Cr (VI, Mo (VI e Se (VI pelo sal de amônio quaternário de quitosana Kinetics and equilibrium of adsorption of oxyanions Cr (VI, Mo (VI and Se (VI by quaternary ammonium chitosan salt

Directory of Open Access Journals (Sweden)

Viviane A. Spinelli

2005-07-01

Full Text Available O sal quaternário de quitosana foi sintetizado com cloreto de glicidil trimetil amônio. A modificação química foi caracterizada por espectrometria no IV, RMN de 13C e ¹H, e mmol/g de grupos quaternários presentes na matriz polimérica por condutimetria. A remoção de Cr (VI, Mo (VI e Se (VI, em meio aquoso, foi investigada em processo de batelada. A adsorção mostrou ser dependente do pH para o Cr (VI e Se (VI, com um pH ótimo de adsorção, entre 4,0 a 6,0. Para o Mo (VI a adsorção manteve-se quase constante no intervalo de pH entre 4,0 e 11,5. O modelo de isoterma de Langmuir descreveu melhor os dados de equilíbrio na faixa de concentração investigada. No presente estudo, um grama do sal quaternário de quitosana reticulado com glutaraldeído adsorveu 68,3 mg de Cr, 63,4 mg de Mo e 90,0 mg de Se. A velocidade de adsorção, no processo, segue a equação cinética de pseudo segunda-ordem, sendo que o equilíbrio para os três íons foi alcançado próximo aos 200 minutos. A análise dispersiva de raios-X para o Cr (VI mostrou que o principal mecanismo de adsorção é a troca iônica entre os íons Cl- da superfície do polímero pelos oxiânions. O trocador aniônico apresentou a seguinte ordem de seletividade: Cr (VI > Mo (VI > Se (VI.Quaternary chitosan salt was synthesized in the presence of glycidyl trimetyl ammonium chloride. The polymer was characterized by spectroscopic techniques: infrared, 13C and ¹H NMR, while the amount of quaternary ammonium groups was obtained by condutimetry. The removal of Cr (VI, Mo (VI and Se (VI from aqueous solutions was carried out in batch adsorption processes. The process seemed to be pH dependent for Cr (VI and Se (VI with an optimum pH ranging from 4.0 to 6.0; while for Mo (VI the adsorption remained almost constant within the range between 4.0 and 11.5. The Langmuir isotherm model provided the best fit of the equilibrium data over the whole concentration investigated. In the experiment

U(VI) sorption on kaolinite. Effects of pH, U(VI) concentration and oxyanions

International Nuclear Information System (INIS)

Liang Gao; Ziqian Yang; Keliang Shi; Xuefeng Wang; Zhijun Guo; Wangsuo Wu

2010-01-01

U(VI) sorption on kaolinite was studied as functions of contact time, pH, U(VI) concentration, solid-to-liquid ratio (m/V) by using a batch experimental method. The effects of sulfate and phosphate on U(VI) sorption were also investigated. It was found that the sorption kinetics of U(VI) can be described by a pseudo-second-order model. Potentiometric titrations at variable ionic strengths indicated that the titration curves of kaolinite were not sensitive to ionic strength, and that the pH of the zero net proton charge (pH PZNPC ) was at 6.9. The sorption of U(VI) on kaolinite increased with pH up to 6.5 and reached a plateau at pH >6.5. The presence of phosphate strongly increased U(VI) sorption especially at pH <5.5, which may be due to formation of ternary surface complexes involving phosphate. In contrast, the presence of sulfate did not cause any apparent effect on U(VI) sorption. A double layer model was used to interpret both results of potentiometric titrations and U(VI) sorption on kaolinite. (author)

KENO-VI Primer: A Primer for Criticality Calculations with SCALE/KENO-VI Using GeeWiz

International Nuclear Information System (INIS)

Bowman, Stephen M.

2008-01-01

The SCALE (Standardized Computer Analyses for Licensing Evaluation) computer software system developed at Oak Ridge National Laboratory is widely used and accepted around the world for criticality safety analyses. The well-known KENO-VI three-dimensional Monte Carlo criticality computer code is one of the primary criticality safety analysis tools in SCALE. The KENO-VI primer is designed to help a new user understand and use the SCALE/KENO-VI Monte Carlo code for nuclear criticality safety analyses. It assumes that the user has a college education in a technical field. There is no assumption of familiarity with Monte Carlo codes in general or with SCALE/KENO-VI in particular. The primer is designed to teach by example, with each example illustrating two or three features of SCALE/KENO-VI that are useful in criticality analyses. The primer is based on SCALE 6, which includes the Graphically Enhanced Editing Wizard (GeeWiz) Windows user interface. Each example uses GeeWiz to provide the framework for preparing input data and viewing output results. Starting with a Quickstart section, the primer gives an overview of the basic requirements for SCALE/KENO-VI input and allows the user to quickly run a simple criticality problem with SCALE/KENO-VI. The sections that follow Quickstart include a list of basic objectives at the beginning that identifies the goal of the section and the individual SCALE/KENO-VI features that are covered in detail in the sample problems in that section. Upon completion of the primer, a new user should be comfortable using GeeWiz to set up criticality problems in SCALE/KENO-VI. The primer provides a starting point for the criticality safety analyst who uses SCALE/KENO-VI. Complete descriptions are provided in the SCALE/KENO-VI manual. Although the primer is self-contained, it is intended as a companion volume to the SCALE/KENO-VI documentation. (The SCALE manual is provided on the SCALE installation DVD.) The primer provides specific examples of

Vitenskapelig usikkerhet – etiske utfordringer for forskning og forvaltning

Directory of Open Access Journals (Sweden)

Frøydis Gillund

2007-11-01

Full Text Available En stor del av dagens forskningsaktivitet er knyttet til utvikling av ny teknologi. Teknologiutvikling anses gjerne som et gode, fordi den bidrar til økt eller ny bruk av naturlige ressurser til beste for menneskers generelle levekår og helse, samt miljøet og samfunnet som helhet. Bruk av ny teknologi innebærer imidlertid også risiko for uønskede effekter. Risikovurderinger er ofte preget av vitenskapelig usikkerhet, spesielt med hensyn til effekter som oppstår over tid. Denne usikkerheten reiser nye etiske dilemmaer og gjør det nødvendig med en kritisk vurdering av kunnskapsgrunnlaget. I denne artikkelen fokuserer vi på hvilke etiske utfordringer vitenskapelig usikkerhet har for forskning og forvaltning, og vi vil se nærmere på bruk av DNA-vaksiner i oppdrettsnæring. Vi argumenterer for at det er viktig å anerkjenne kvalitative former for vitenskapelig usikkerhet, som går utover det som uttrykkes i statistiske termer. Walker & Harremoeës (W&H usikkerhetsanalyse presenteres som en metode for å identifisere og systematisere vitenskapelig usikkerhet av kvalitativ karakter. En slik analyse kan øke forskeres evne til å reflektere over og kommunisere usikkerhet knyttet til eget arbeid. Vi argumenterer videre for at kommunikasjon av vitenskapelig usikkerhet bør være en del av forskerens etiske ansvar, blant annet for å stimulere føre-var-basert forskning og forvaltning. En helhetsvurdering av nytte, risikomomenter og usikkerhet kan best oppnås gjennom en tverrfaglig tilnærming. Det vil bidra til at de implisitte verdiene som er assosiert til bruk av ny teknologi blir bedre belyst.http://dx.doi.org/10.5324/eip.v1i1.1685

Pengembangan Sistem Informasi Akuntansi Dan Pengelolaan Keuangan Modul Penganggaran Berbasis Web Menggunakan Teknologi Java Dan Postgresql

Directory of Open Access Journals (Sweden)

Hari Rakhmanto Zauhar

2012-09-01

Full Text Available Banyaknya fungsi yang dijalankan di satuan kerja pemerintah telah didukung oleh teknologi informasi yaitu berupa aplikasi-aplikasi yang banyak pula. Namun banyaknya aplikasi tersebut menyebabkan munculnya permasalahan baru yaitu sistem database yang masih terpisah. Saat ini akan dikembangkan suatu aplikasi yang bernama Sistem Informasi Akuntansi dan Pengelolaan Keuangan yang akan mengintegrasikan semua aplikasi operasional di satuan kerja. Aplikasi ini berbasis web dan menggunakan teknologi Java dan PostgreSQL Salah satu fungsi yang wajib ikut diintegrasikan aplikasinya adalah fungsi penganggaran dengan aplikasi Rencana Kerja Anggaran-Kementerian Negara/Lembaga Daftar Isian Pelaksanaan Anggaran. Aplikasi ini sangat penting karena merupakan awal dari proses pengelolaan keuangan. Jika aplikasi ini tidak ikut diintegrasikan maka akan berpotensi tidak sinkronnya data Daftar Isian Pelaksanaan Anggaran dari aplikasi Rencana Kerja Anggaran-Kementerian Negara/Lembaga Daftar Isian Pelaksanaan Anggaran dengan aplikasi Surat Perintah Membayar. Terpisahnya database dari aplikasi Rencana Kerja Anggaran-Kementerian Negara/Lembaga Daftar Isian Pelaksanaan Anggaran dengan aplikasi Surat Perintah Membayar juga dapat menimbulkan potensi tindakan kriminal manipulasi data Daftar Isian Pelaksanaan AnggaranDengan diintegrasikannya aplikasi Rencana Kerja Anggaran-Kementerian Negara/Lembaga Daftar Isian Pelaksanaan Anggaran ke dalam aplikasi Sistem Informasi Akuntansi dan Pengelolaan Keuangan maka dapat meningkatkan kinerja satuan kerja sekaligus meningkatkan kualitas laporan keuanganya

Cranial mononeuropathy VI

Science.gov (United States)

... Abducens palsy; Lateral rectus palsy; VIth nerve palsy; Cranial nerve VI palsy; Sixth nerve palsy; Neuropathy - sixth nerve ... Cranial mononeuropathy VI is damage to the sixth cranial nerve. This nerve is also called the abducens nerve. ...

PEMBUATAN PROTOTIPE APLIKASI WEB SERVICES BERBASIS XML MENGGUNAKAN TEKNOLOGI J2EE DENGAN STUDI KASUS RESERVASI HOTEL

Directory of Open Access Journals (Sweden)

Isye Arieshanti

2005-01-01

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;} Dalam era globalisasi, para pelaku bisnis secara intensif melakukan usaha-usaha untuk memasuki pasar global. Suatu perusahaan semakin membutuhkan transaksi  bisnis yang bersifat fleksibel, yang bisa dilakukan dengan siapa saja, kapan saja dan dimana saja. Tentunya sistem informasi yang dimiliki perusahaan tersebut harus bisa berkomunikasi dengan sistem yang dimiliki oleh patner bisnis, tanpa harus terlalu banyak perjanjian dan persetujuan. Hal ini berarti diperlukan standard infrastruktur sederhana untuk pertukaran data bisnis.Kebutuhan ini dapat dipenuhi oleh teknologi web service sebagai teknologi yang menyediakan infrastruktur sederhana bagi pelaku bisnis untuk berkomunikasi melalui pertukaran pesan XML. Pada Penelitian ini dikembangkan sebuah prototipe aplikasi web service dengan studi kasus reservasi hotel melalui perantara broker. Studi kasus ini dipilih karena dapat merepresentasikan sistem yang terdistribusi. Dimana broker berperan sebagai penghubung antara customer dan beberapa sistem yang terdistribusi.Pada pembuatan aplikasi ini dipilih teknologi J2EE karena framework J2EE yang telah ada mendukung penerapan web service. Dan selain itu, J2EE bersifat netral terhadap berbagai macam platform (tidak

Enzymatic reduction of U(VI) in groundwaters; Reduction enzymatique de U(VI) dans des eaux souterraines

Energy Technology Data Exchange (ETDEWEB)

Addelouas, A.; Gong, W. [Center for Radioactive Waste Management, Advanced Materials Laboratory, 1001 University, Albuquerque (United States); Lutze, W.; Nuttall, E. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Chemical and Nuclear Engineering; Fritz, B.; Crovisier, J.L. [Centre National de la Recherche Scientifique (CNRS), 67 - Strasbourg (France). Centre de Sedimentologie et Geochimie de la Surface

1999-03-01

The use of enzymatic reduction of U(VI) in remediation of groundwater contaminated with U(VI) is receiving considerable attention. Certain strains of bacteria can combine the oxidation of an organic compound to the reduction of U(VI) to U(IV), which precipitates as uraninite. In the present study, we tested the reduction of U(VI) in groundwaters with various origins and compositions. In all groundwaters u(VI) was reduced by sulfate reducing bacteria that had been activated by ethanol and tri-metaphosphate. The reduction rate of U(VI) depends on sulfate concentration in water and the abundance of bacteria in the system. This work shows that bacteria capable of U(VI) reduction are ubiquitous in nature, and suggests the possibility of a large application of the enzymatic reduction of U(VI) for in situ clean up of groundwaters contaminated with uranium. (authors) 12 refs.

POTENSI ATMOSFER DALAM PEMBENTUKAN AWAN KONVEKTIF PADA PELAKSANAAN TEKNOLOGI MODIFIKASI CUACA DI DAS KOTOPANJANG DAN DAS SINGKARAK 2010

OpenAIRE

Syaifullah, M Djazim

2011-01-01

Kajian potensi atmosfer terhadap proses pembentukan dan pertumbuhan awan konvektifpada saat pelaksanaan Teknologi Modifikasi Cuaca (TMC) telah dilakukan dengan datapengamatan sounding dari stasiun Tabing Sumatera Barat. Sebanyak 330 buah datapengamatan harian jam 00Z dan 12Z dari Juni sampai dengan Nopember 2010 telahdianalisis. Dengan aplikasi RAOB analisis dilakukan untuk menentukan parameterdan indeks radiosonde sebagai penduga potensi atmosfer di wilayah tersebut. Hasilanalisis kandungan ...

Teknologi og etiske problematikker for selvkørende biler

OpenAIRE

Clarke, Danijel Charles; Thulstrup, Frederik Zeilberger; Gjermandsen, Niels Henrik Lind; Brodthagen, Morten

2016-01-01

Dette project undersøger de etiske problematikker, love omkring selvkørerende biler og hvordan mansikre sig at lovene fastlagt af regeringen, bliver overholdt. Vi har kigget på teknologien bag to selvkø-rerende biler, Tesla Model S og Junior. Til objektgenkendelse benytter Junior et Argumented DiscreteBayes Filter, mens Model S benytter et neuralt netværk. Til ruteplanlægning kunne vi kun finde algoritmerJunior benytter, som er baseret på A* algoritmen.Når selvkørerende biler bliver testet i ...

PEMODELAN TERAS UNTUK ANALISIS PERHITUNGAN KONSTANTA MULTIPLIKASI REAKTOR HTR-PROTEUS

Directory of Open Access Journals (Sweden)

Zuhair Zuhair

2015-04-01

Full Text Available PTRKN sebagai salah satu unit kerja di BATAN dengan tugas pokok dan fungsi yang berkaitan erat dengan teknologi reaktor dan keselamatan nuklir, menaruh perhatian khusus pada konsep reaktor pebble bed. Dalam makalah ini pemodelan reaktor pebble bed HTR-PROTEUS dilakukan dengan program transport Monte Carlo MCNP5. Partikel bahan bakar berlapis TRISO dimodelkan secara detail dan eksak dimana distribusi acak partikel ini dalam bola bahan bakar didekati menggunakan array teratur kisi SC dengan fraksi packing 5,76% tanpa zona eksklusif. Model teras pebble bed didekati dengan memanfaatkan kisi teratur dari bola yang disusun sebagai kisi BCC berdasarkan sel berulang yang digenerasi dari sejumlah sel satuan. Hasil perhitungan MCNP5 memperlihatkan kesesuaian yang sangat baik dengan eksperimen, walaupun teras HTR-PROTEUS diprediksi lebih reaktif daripada pengukuran, khususnya di teras 4.2 dan 4.3. Pustaka ENDF/B-VI menunjukkan konsistensi dengan estimasi keff paling akurat dibandingkan pustaka ENDF/B-V, terutama ENDF/B-VI (66c. Deviasi estimasi keff yang dihitung dengan eksperimen dikaitkan sebagai konsekuensi dari komposisi reflektor grafit yang dispesifikasikan. Komparasi yang dibuat memperlihatkan bahwa MCNP5 menghasilkan keff teras HTR-PROTEUS lebih presisi daripada hasil dari MCNP4B dan MCNPBALL. Hasil ini menyimpulkan bahwa, sukses metodologi pemodelan ini menjustifikasi aplikasi MCNP5 untuk analisis reaktor pebble bed lainnya. Kata kunci: pemodelan teras HTR-PROTEUS, konstanta multiplikasi, MCNP5   PTRKN as a working unit in BATAN whose main duties and functions are related to reactor technology and nuclear safety, consern attention to pebble bed reactor concept. In this paper modeling of HTR-PROTEUS pebble bed reactor was done using Monte Carlo transport code MCNP5. The TRISO coated fuel particle is modeled in detailed and exact manner where random distributions of these particles in fuel pebble is approximated by using regular array of SC lattice

Registration, Evaluation, Authorisation, Categorisation and Tools to Evaluate Nanomaterials – Opportunities and Weaknesses (REACT NOW)

OpenAIRE

Hansen, Steffen Foss

2018-01-01

Uanset om vi er klar over det eller ej, er nanoteknologi og nanomaterialer i det seneste årti blevet en integreret del af vores liv. Vi er gået ind i en fase, hvor den tidlige hype om fordelene ved denne – mildt sagt forbløffende – teknologi er forbi. Siden nanoteknologiens spæde begyndelse er der blevet rejst tvivl om de eventuelle negative miljø- og sundhedseffekter af nanomaterialer. Men som tiden er gået, er der blevet mere og mere stille omkring disse. Det er ikke, fordi vi har løst udfo...

TechTutorer - en ny måde at integrere teknologi i læreruddannelsen?

DEFF Research Database (Denmark)

Heiberg, Tobias; Arstorp, Ann-Thérèse

’TechTutor-enheden’ skal ses. I rapporten uddybes initiativet, men helt enkelt kan TechTutorerne beskrives som en gruppe af lærerstuderende med særlige kompetencer og interesser inden for det teknologiske felt. Og de samarbejder som TechTutorer om udbud af diverse kursusforløb samt udvikling af...... læreruddannelsen, når det kommer til didaktisering og implementering af teknologi – alt sammen med rapportens forfattere som koordinerende og kvalificerende element. TechTutor-initiativet skal altså overordnet ses som et eksperiment, der centrerer sig omkring nye vinkler på kvalificering og optimering af...

Uranium(VI) speciation by spectroscopy

International Nuclear Information System (INIS)

Meinrath, G.

1997-01-01

The application of UV-Vis and time-resolved laser-induced fluorescence (TRLF) spectroscopies to direct of uranium(VI) in environmental samples offers various prospects that have, however, serious limitations. While UV-Vis spectroscopy is probably not sensitive enough to detect uranium(VI) species in the majority of environmental samples, TRLFS is principially able to speciate uranium(VI) at very low concentration levels in the nanomol range. Speciation by TRLFS can be based on three parameters: excitation spectrum, emission spectrum and lifetime of the fluorescence emission process. Due to quenching effects, the lifetime may not be expected to be as characteristics as, e.g., the emission spectrum. Quenching of U(VI) fluorescence by reaction with organic substances, inorganic ions and formation of carbonate radicals is one important limiting factor in the application of U(VI) fluorescence spectroscopy. Fundamental photophysical criteria are illustrated using UV-Vis and fluorescence spectra of U(VI) hydrolysis and carbonato species as examples. (author)

TEKNOLOGI BERBASIS LAYANAN MANDIRI UNTUK KASUS E-BANKING

Directory of Open Access Journals (Sweden)

Edy Purwo Saputro

2010-12-01

Full Text Available Revolusi dan evolusi perkembangan teknologi informasi dan sistem informasi memicu transformasi dalam semua bidang dan hal ini kemudian menimbulkan fenomena tentang e-lifestyle yaitu mulai dari e-mail, e-banking, e-shopping, e-book, e-wallets, e-learning, e-news, e-commerce, e-trading, e-election, e-business, e-market, e-service dan e-cards. Di satu sisi, e-lifestyle memberikan banyak kemudahan tapi di sisi lain ini menimbulkan ancaman terutama dikaitkan dengan jaminan keamanan di semua transaksi yang terkait e-lifestyle. Terkait ini, jika aspek keamanan tidak mendapatkan prioritas perhatian dari semua pihak, maka akan terjadi fenomena: ‘don’t trust anyone, don’t trust anything’ dan kepercayaan akan menjadi “blind trust”. Hal ini tentu sangat dimungkinkan karena di cyber economy ada berbagai kasus yang mendasari misalnya ‘phising’ (kegiatan pengiriman e-mail palsu yang di dalamnya terkandung link ke sebuah situs web, yang bisa mengarahkan seseorang untuk menyerahkan identitas pribadi, atau ‘clickjacking’ (yaitu kode jahat yang tersembunyi di balik tombol klik di sebuah situs yang dikunjungi oleh seseorang. Aspek keamanan menjadi sangat penting karena fakta perkembangan e-lifestyle di Indonesia pada umumnya dan adopsi e-banking khususnya masih berada pada tahap pertumbuhan

Diverse anaerobic Cr(VI) tolerant bacteria from Cr(VI)-contaminated 100H site at Hanford

Science.gov (United States)

Chakraborty, R.; Phan, R.; Lam, S.; Leung, C.; Brodie, E. L.; Hazen, T. C.

2007-12-01

Hexavalent Chromium [Cr(VI)] is a widespread contaminant found in soil, sediment, and ground water. Cr(VI) is more soluble, toxic, carcinogenic, and mutagenic compared to its reduced form Cr(III). In order to stimulate microbially mediated reduction of Cr(VI), a poly-lactate compound HRC was injected into the chromium contaminated aquifers at site 100H at Hanford. Based on the results of the bacterial community composition using high-density DNA microarray analysis of 16S rRNA gene products, we recently investigated the diversity of the dominant anaerobic culturable microbial population present at this site and their role in Cr(VI) reduction. Positive enrichments set up at 30°C using specific defined anaerobic media resulted in the isolation of an iron reducing isolate strain HAF, a sulfate reducing isolate strain HBLS and a nitrate reducing isolate, strain HLN among several others. Preliminary 16S rDNA sequence analysis identifies strain HAF as Geobacter metallireducens, strain HLN as Pseudomonas stutzeri and strain HBLS as a member of Desulfovibrio species. Strain HAF isolated with acetate as the electron donor utilized propionate, glycerol and pyruvate as alternative carbon sources, and reduced metals like Mn(IV) and Cr(VI). Growth was optimal at 37°C, pH of 6.5 and 0% salinity. Strain HLN isolated with lactate as electron donor utilized acetate, glycerol and pyruvate as alternative carbon sources, and reduced metals like Mn(IV) and Cr(VI). Optimal growth was observed at 37°C, at a pH of 7.5 and 0.3% salinity. Anaerobic active washed cell suspension of strain HLN reduced almost 95 micromolar Cr(VI) within 4 hours relative to controls. Further, with 100 micromolar Cr(VI) as the sole electron acceptor, cells of strain HLN grew to cell numbers of 4.05X 107/ml over a period of 24hrs after an initial lag, demonstrating direct enzymatic Cr(VI) reduction by this species. 10mM lactate served as the sole electron donor. These results demonstrate that Cr(VI

KOSEP PEMAHAMAN DAN TEKNOLOGI PENGELOLAAN SAMPAH DI RUMAH SUSUN SEWA

Directory of Open Access Journals (Sweden)

Henita Rahmayanti

2016-01-01

Full Text Available Penelitian ini bertujuan untuk merencanakan pengelolaan sampah di Tempat Penampungan Sampah yang terdapat di rumah susun sewa di Jakarta. Proses pengelolaan yang akan dilakukan dengan cara menanamkan konsep pemahaman pemilahan sampah organik dan anorganik di rumah masing-masing dan sistem pembuangan menggunakan saluran pembuangan secara terpisah. Prinsip pengelolaan sampah yang akan diterapkan yaitu merubah sampah yang tidak berguna menjadi bernilai guna. Semua sampah diolah dengan baik di Tempat Penampungan sampah sehingga tidak ada sampah yang diangkut keluar (Zero Waste. Teknologi pengelolaan sampah organik menggunakan sistem Anaerobic Digester sedangkan untuk pengelolaan sampah anorganik menggunakan sistem 4R (Reduce, Reuse, Recycle, Replace. Hasil dari pengelolaan sampah organik adalah kompos, limbah cair untuk budidaya ikan lele serta biogas. Untuk hasil sampah anorganik akan dijual kepada pengumpul barang bekas, digunakan sebagai bahan yang dapat diolah untuk berbagai kreasi dan dapat mempunyai nilai ekonomis. Proses ini memerlukan peran aktif dari masyarakat untuk mengelola sampah secara terus menerus sehingga dapat dijadikan contoh untuk tempat-tempat lain.

Kesiapan Operator Seluler dalam Mengimplementasikan Teknologi Long Term Evolution (LTE

Directory of Open Access Journals (Sweden)

Sri Ariyanti

2012-06-01

Full Text Available Penelitian ini bertujuan untuk mengetahui seberapa besar kesiapan operator seluler dalam mengimplementasikan teknologi Long Term Evolution (LTE. Model penelitian dengan menggunakan mengadopsi teknik Net Readiness Framwork. Adapun kriteria pengukurannya terdiri dari Leadership, Governance, Competencies dan Technology. Pengumpulan data dilakukan dengan menyebarkan kuesioner kepada operator seluler di Indonesia dan melakukan wawancara kepada regulator. Kajian ini menggunakan teknik analisis data kuantitatif deskriptif. Hasil penelitian menunjukkan bahwa PT. Axis, PT. HCPT dan PT. Telkomsel mempunyai tingkat kesiapan LTE Visionary yang berarti perusahaan sangat antusias dalam perubahan dan lebih dahulu mengambil resiko untuk mengimplementasikan LTE dalam organisasinya yang merupakan bagian yang tak terpisahkan proses bisnis perusahaan. PT. Indosat dan PT. XL mempunyai nilai kesiapan LTE leader  yang berarti perusahaan mampu mengadaptasi perubahan dan menginspirasi organsiasi lain dalam penerapan LTE. PT. Smartfren pada tingkat kesiapan LTE savvy yang berarti operator seluler memahami sebab dan efek dari perubahan dari munculnya LTE terhadap organisasi, namun belum melakukan adaptasi.

PENENTUAN KOLABORASI PENELITIAN DAN DISTRIBUSI PENGARANG PADA JURNAL TEKNOLOGI INDONESIA (THE DETERMINATIONS OF RESEARCH COLLABORATION AND AUTHORS DISTRIBUTION IN THE JURNAL TEKNOLOGI INDONESIA

Directory of Open Access Journals (Sweden)

Engkos Koswara Natakusumah

2014-06-01

Full Text Available This study aims to determine of research collaboration and authors distribution based on the data and informationmentioned in the Jurnal Teknologi Indonesia (JTI during 5 years, from 2007 up to 2011. To reach this aims, theresearch uses methodology of bibliometric analysis to analyse the citation appeared in every last page of the articlepublished in the JTI; including distribution of articles each year, the number of contributors, the authorship, thedistribution of article languages, the single and many authors who wrote write the articles, the number of documentcited by outhors, and average number of references in an article. The bibliometrics data come from 80 articles,ranging from volume 30 up to volume 34. Then the data are tabulated, analysed and described for the purpose tomake conclusion of the research. The results show that there are domination of publication contribution by auhtors’collaboration in the journal, have significant range of research collaboration and have high rank of publication by 4researchers of 7, 6 and 5 articles published. 

Enzymatic reduction of U(VI) in groundwaters

International Nuclear Information System (INIS)

Addelouas, A.; Gong, W.; Lutze, W.; Nuttall, E.; Fritz, B.; Crovisier, J.L.

1999-01-01

The use of enzymatic reduction of U(VI) in remediation of groundwater contaminated with U(VI) is receiving considerable attention. Certain strains of bacteria can combine the oxidation of an organic compound to the reduction of U(VI) to U(IV), which precipitates as uraninite. In the present study, we tested the reduction of U(VI) in groundwaters with various origins and compositions. In all groundwaters u(VI) was reduced by sulfate reducing bacteria that had been activated by ethanol and tri-metaphosphate. The reduction rate of U(VI) depends on sulfate concentration in water and the abundance of bacteria in the system. This work shows that bacteria capable of U(VI) reduction are ubiquitous in nature, and suggests the possibility of a large application of the enzymatic reduction of U(VI) for in situ clean up of groundwaters contaminated with uranium. (authors)

Enzymatic U(VI) reduction by Desulfosporosinus species

International Nuclear Information System (INIS)

Suzuki, Y.; Kelly, S.D.; Kemner, K.M.; Banfield, J.F.

2004-01-01

Here we tested U(VI) reduction by a Desulfosporosinus species (sp.) isolate and type strain (DSM 765) in cell suspensions (pH 7) containing 1 mM U(VI) and lactate, under an atmosphere containing N 2 -CO 2 -H 2 (90: 5: 5). Although neither Desulfosporosinus species (spp.) reduced U(VI) in cell suspensions with 0.25% Na-bicarbonate or 0.85% NaCl, U(VI) was reduced in these solutions by a control strain, desulfovibrio desulfuricans (ATCC 642). However, both Desulfosporosinus strains reduced U(VI) in cell suspensions depleted in bicarbonate and NaCl. No U(VI) reduction was observed without lactate and H 2 electron donors or with heat-killed cells, indicating enzymatic U(VI) reduction. Uranium(VI) reduction by both strains was inhibited when 1 mM CuCl 2 was added to the cell suspensions. Because the Desulfosporosinus DSM 765 does not contain cytochrome c 3 used by Desulfovibrio spp. to reduce U(VI), Desulfosporosinus species reduce uranium via a different enzymatic pathway. (orig.)

Kiintoainehäviöselvitys

OpenAIRE

Ylimys, Jussi

2014-01-01

Teoriaosassa käydään läpi yleisesti pyörrepuhdistuslaitoksen toimintaa sekä kiintoainehäviöitä paperi- ja kartonkitehtailla. Tämän opinnäytetyön tarkoituksena oli tutkia Metsä Boardin Kyröskosken tehtaan kiintoainehäviötä. Työssä selvitettiin, minkälaista kiintoainetta jätevesilaitokselle päätyy ja miksi. Selvityksen kohteena oli myös, missä kohteissa kiintoainehäviöt tarkalleen syntyvät ja kuinka paljon häviötä tapahtuu. Kahden edellä mainitun tiedon perusteella selvitettiin, kuinka palj...

PENERAPAN TEKNOLOGI VOIP UNTUK MENGOPTIMALKAN PENGGUNAAN JARINGAN INTRANET KAMPUS UNIVERSITAS UDAYANA

Directory of Open Access Journals (Sweden)

Pande Ketut Sudiarta

2009-12-01

Full Text Available Jaringan intranet Universitas Udayana telah menghubungkan ketiga lokasi kampus, yaitu Kampus Bukit, Kampus Sudirman, dan Kampus Nias.  Lokasi kampus yang terpisah-pisah dan kampus Bukit yang memiliki area yang cukup luas memerlukan prasarana teleponi yang memadai.  Selama ini, komunikasi teleponi masih memanfaatkan provider seperti PT Telkom, walaupun komunikasi telepon hanya untuk komunikasi antar fakultas atau antar fakultas dengan rektorat di area kampus bukit.  Demikian juga untuk komunikasi telepon antar lokasi kampus yang berbeda. Walaupun beberapa fakultas dan juga gedung Rektorat memiliki perangkat PABX namun keberadaan kebanyakan hanya melayani komunikasi dalam satu gedung saja.  Pemanfaatan intranet kampus UNUD baru dimanfaatkan untuk akses Internet, akses Sistem Informasi dan untuk videoconference. Dengan beban trafik yang ada, jaringan intranet masih memungkinkan untuk dibebani dengan trafik yang lebih tinggi. Dengan demikian, untuk mengoptimalkan pemanfaatan bandwith,  diupayakan dengan mengembangakan sistem teleponi berbasis VoIP yang memanfaatkan infrastruktur yang ada. Tujuan yang ingin dicapai adalah menyediakan fasilitas telepon internal kampus yang tidak berbayar. Melalui teknologi VoIP ini,  komunikasi dapat dilakukan dengan beberapa cara baik menggunakan telepon analog maupun softphone yang dapat diinstall di masing-masing PC atau laptop. Hal ini nanti tentu akan memberikan efisiensi waktu bagi civitas karena mudah dihubungi dan secara langsung akan berdampak pada efisiensi biaya telekomunikasi di kampus. Infrastruktur yang dikembangkan menggunakan protokol SIP memanfaatkan Free Software Linux Fedora sebagai Operating System, Asterisk dan Ondo sebagai aplikasi server.  Di sisi pemakai, perangkat telepon dapat menggunakan dua model, pertama menggunakan softphone  yang ditujukan untuk personal dengan memanfaatkan nomor induk pegawai (NIP atau nomor induk mahasiswa (NIM sebagai nomor telepon. Model telepon ini aksesnya

Peroxo complexes of molybdenum(VI), tungsten(VI), uranium(VI), zirconium(IV) and thorium(IV) ions containing tridentate Schiff bases derived from salicylaldehyde and amino acids

International Nuclear Information System (INIS)

Tarafder, M.T.H.; Khan, A.R.

1997-01-01

The synthesis of peroxo complexes of molybdenum(VI), tungsten(VI), uranium(VI), zirconium(IV), thorium(IV) and their possible oxygen transfer reactions is presented. An attempt has also been made to study the size of the metal ions and the electronic effect derived from the tridentate Schiff bases on the v 1 (O-O) mode of the complexes in their IR spectra

Studi Migrasi Public Switched Telephone Network (Pstn) Menuju Jaringan Telekomunikasi Berbasis Paket Next Generation Network (Ngn) Dengan Teknologi Softswitch

OpenAIRE

Suseno, Andrias Danang; Najib, Warsun; Samiyono, -

2009-01-01

Public Switched Telephone Network (PSTN) adalah sistem telekomunikasi berbasis circuit-switched. Pada awalnya PSTN hanya menyediakan layanan voice. PSTN sekarang telah berkembang ke arah pelayanan komunikasi data yang didorong oleh berkembangnya dunia internet dengan Internet Protokol (IP)-nya. Telah muncul teknologi Voice over IP (VoIP) yang mampu melewatkan trafik voice pada jaringan data dengan mengubah voice menjadi paket. VoIP telah mendorong trend/kecenderungan terjadinya konvergensi an...

ENDF-201, ENDF/B-VI summary documentation supplement 1, ENDF/HE-VI summary documentation

International Nuclear Information System (INIS)

McLane, V.

1996-12-01

The National Nuclear Data Center (NNDC) provides coordination for and serves as the secretariat to the Cross Section Evaluation Working Group (CSWEG). CSEWG is responsible for the oversight of the ENDF/B Evaluated Nuclear Data File. All data are checked and reviewed by CSEWG, and the file is maintained at the NNDC. For a description of the ENDF/B-VI file, see the ENDF-102 Data Formats and Procedures for the Evaluated Nuclear Data File ENDF-6. The purpose of this addendum to the ENDF/B-VI Summary Documentation is to provide documentation of Releases 1, 2, 3, and 4 for the ENDF/B-VI and ENDF/HE-VI evaluated nuclear data libraries. These releases contain many new and revised evaluations for the neutron, photo-atomic interaction, radioactive decay data, spontaneous fission product yield, neutron-induced fission product yield, thermal neutron scattering, proton, deuteron, and triton sublibraries. The summaries have been extracted mainly from the ENDF/B-VI File 1 comments (MT = 451), which have been checked, edited, and may also include supplementary information. Some summaries have been provided by the evaluators in electronic format, while others are extracted from reports on the evaluations. All references have been checked and corrected, or updated where appropriate. A list of the laboratories which have contributed evaluations used in ENDF/B-VI is given

ENDF-201, ENDF/B-VI summary documentation supplement 1, ENDF/HE-VI summary documentation

Energy Technology Data Exchange (ETDEWEB)

McLane, V.

1996-12-01

The National Nuclear Data Center (NNDC) provides coordination for and serves as the secretariat to the Cross Section Evaluation Working Group (CSWEG). CSEWG is responsible for the oversight of the ENDF/B Evaluated Nuclear Data File. All data are checked and reviewed by CSEWG, and the file is maintained at the NNDC. For a description of the ENDF/B-VI file, see the ENDF-102 Data Formats and Procedures for the Evaluated Nuclear Data File ENDF-6. The purpose of this addendum to the ENDF/B-VI Summary Documentation is to provide documentation of Releases 1, 2, 3, and 4 for the ENDF/B-VI and ENDF/HE-VI evaluated nuclear data libraries. These releases contain many new and revised evaluations for the neutron, photo-atomic interaction, radioactive decay data, spontaneous fission product yield, neutron-induced fission product yield, thermal neutron scattering, proton, deuteron, and triton sublibraries. The summaries have been extracted mainly from the ENDF/B-VI File 1 comments (MT = 451), which have been checked, edited, and may also include supplementary information. Some summaries have been provided by the evaluators in electronic format, while others are extracted from reports on the evaluations. All references have been checked and corrected, or updated where appropriate. A list of the laboratories which have contributed evaluations used in ENDF/B-VI is given.

24 CFR 971.11 - HOPE VI developments.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false HOPE VI developments. 971.11... § 971.11 HOPE VI developments. Developments with HOPE VI implementation grants that have approved HOPE... with reasonable revitalization plans. Future HUD actions to approve or deny proposed HOPE VI...

Technology-derived storage solutions for stabilizing insulin in extreme weather conditions I: the ViViCap-1 device.

Science.gov (United States)

Pfützner, Andreas; Pesach, Gidi; Nagar, Ron

2017-06-01

Injectable life-saving drugs should not be exposed to temperatures 30°C/86°F. Frequently, weather conditions exceed these temperature thresholds in many countries. Insulin is to be kept at 4-8°C/~ 39-47°F until use and once opened, is supposed to be stable for up to 31 days at room temperature (exception: 42 days for insulin levemir). Extremely hot or cold external temperature can lead to insulin degradation in a very short time with loss of its glucose-lowering efficacy. Combined chemical and engineering solutions for heat protection are employed in ViViCap-1 for disposable insulin pens. The device works based on vacuum insulation and heat consumption by phase-change material. Laboratory studies with exposure of ViViCap-1 to hot outside conditions were performed to evaluate the device performance. ViViCap-1 keeps insulin at an internal temperature phase-change process and 'recharges' the device for further use. ViViCap-1 performed within its specifications. The small and convenient device maintains the efficacy and safety of using insulin even when carried under hot weather conditions.

Reduction of ferrate(VI) and oxidation of cyanate in a Fe(VI)-TiO2-UV-NCO- system.

Science.gov (United States)

Winkelmann, Kurt; Sharma, Virender K; Lin, Yekaterina; Shreve, Katherine A; Winkelmann, Catherine; Hoisington, Laura J; Yngard, Ria A

2008-08-01

The aqueous photocatalytic degradation of cyanate (NCO(-)), which is a long-lived neurotoxin formed during the remediation of cyanide in industrial waste streams, was studied in the ferrate(VI)-UV-TiO2-NCO(-) system. Kinetics measurements of the photocatalytic reduction of ferrate(VI) were carried out as a function of [NCO(-)], [ferrate(VI)], [O(2)], light intensity (I(o)), and amount of TiO2 in suspensions at pH 9.0. The photocatalytic reduction rate of ferrate(VI) in the studied system can be expressed as -d[Fe(VI)]/dt=kI(o)(0.5) [NCO(-)] [TiO2]. The rate of photocatalytic oxidation of cyanate with ferrate(VI) was greater than the rate in the analogous system without ferrate(VI). The possibility of involvement of reactive ferrate(V) species for this enhancement was determined by studying the reactivity of ferrate(V) with NCO(-) in a homogeneous solution using a premix pulse radiolysis technique. The rate constant for the reaction of ferrate(V) and NCO(-) in alkaline medium was estimated to be (9.60+/-0.07) x 10(2) M(-1) s(-1), which is much slower than the ferrate(VI) self-decomposition reaction (k approximately 10(7) M(-1) s(-1)). An analysis of the kinetic data in the Fe(VI)-UV-TiO2-NCO(-) system suggests that ferrate(V) is not directly participating in the oxidation of cyanate. Possible reactions in the system are presented to explain results of ferrate(VI) reduction and oxidation of cyanate.

SISTEM PENDUKUNG KEPUTUSAN TEKNOLOGI PENANGANAN DAN KELAYAKAN INVESTASI PASCAPANEN KAKAO (Theobroma cacao L. (STUDI KASUS DI KABUPATEN PIDIE JAYA, PROPINSI ACEH

Directory of Open Access Journals (Sweden)

Raida Agustina

2013-06-01

Full Text Available Cocoa beans produced by smallholders have low quality because of gaps in information on post-harvest tecnology. Information is needed to provide decision-support making for choosing one alternative implementation of the handling technology cocoa most appropriate and in accordance with the conditions of its territory which can improve the quality of dried cocoa beans. The purpose of this study was developed an  decision-support system software as a tool for decision making cocoa post-harvest handling, obtain the best alternative based on technical analysis and economic analysis, evaluate the feasibility of investment, and know the value of the sensitivity of each alternative. This study was carried out from July to December 2010 in Bandar Baru sub district, Pidie Jaya district of Aceh province. Survey and interview were used to collecting data. Collected data used to create a database for a decision-support system model of cocoa post-harvest handling technology, which was processed using  the Java programming language. Based on the analysis post harvest technology of cocoa to farmers and investors indicated a mechanical alternative is the best alternative because it produces the greatest benefits. Mechanical alternative  gives farmers a profit of Rp.1,419,279,165 per year and gives investors a profit of Rp. 1,023,246,397 per year and feasibility analysis shows NPV Rp 923,577,155 and the value of R/C ratio of 3 is also available in mechanical alternative. The results of sensitivity analysis on each alternative show that the most influential variables on the profitability of farmers and investors is wage labor, the price of fresh cacao fruit, and the price of dry beans. Keywords: Decision-support system, information, cocoa, post harvest technology   ABSTRAK Biji kakao yang dihasilkan perkebunan rakyat memiliki mutu yang rendah karena adanya kesenjangan dalam informasi mengenai teknologi penanganan pascapanen. Informasi dibutuhkan untuk memberi

Vi har intet lært - hvornår lærer vi det?

DEFF Research Database (Denmark)

Sodemann, Morten

2016-01-01

WHO anså fra i går ikke længere ebola for at være en trussel mod global folkesundhed, så fra i dag er kameraerne slukket i Vestafrika og vi er tilbage hvor vi startede. SDG målene skal have et dansk udtryk, men hvad er de danske kompetencer på globalt plan når sundhed ikke længere er en kerneakti......WHO anså fra i går ikke længere ebola for at være en trussel mod global folkesundhed, så fra i dag er kameraerne slukket i Vestafrika og vi er tilbage hvor vi startede. SDG målene skal have et dansk udtryk, men hvad er de danske kompetencer på globalt plan når sundhed ikke længere er en...

Perancangan Web Interface Institut Teknologi Sepuluh Nopember (ITS Dengan Memperhatikan Aspek Usability

Directory of Open Access Journals (Sweden)

Hendry Setyawans Sutedjo

2012-09-01

Full Text Available Informasi dalam sebuah website atau web diharapkan dapat sampaikan dan diterima oleh pencari informasi dengan mudah. Di dalam Dunia pendidikan, informasi yang ada di dalam web juga diharapkan mampu diterima oleh para penggunanya dengan tujuan media komunikasi online seperti website dapat membantu para pelajar menerima ilmu yang disampaikan melalui media online. Untuk Mengetahui seberapa mudahnya informasi itu ditangkap ditandai dengan seberapa mudah website itu digunakan (usable. Untuk mengetahui seberapa mudah penggunaan suatu website digunakan analisa usability, banyak metode yang dapat digunakan untuk mengidentifikasi masalah usability terutama dari sisi interface web. Heuristic evaluation merupakan salah satu teknik dalam melakukan hal tersebut yang digunakan dalam penelitian ini guna menilai seberapa mudahnya website Institut Teknologi Sepuluh Nopember dalam menyampaikan informasi yang ada. Dalam penelitian ini digunakan juga Quality Function Deployment (QFD untuk mengidentifikasi keinginan pengguna terhadap tampilan dari web ITS

Sistem Reminder Donor Darah dengan Memanfaatkan Teknologi Location Based Service

Directory of Open Access Journals (Sweden)

Ismail Abdus Shobar

2016-11-01

Full Text Available Donor darah merupakan kegiatan kemanusiaan yang bertujuan untuk membantu anggota masyarakat yang membutuhkan darah. Kegiatan donor darah diselenggarakan dan dikelola oleh Palang Merah Indonesia. Menurut catatan Palang Merah Indonesia, secara keseluruhan kebutuhan kantung darah yang tidak terpenuhi melebihi satu juta kantung darah. Untuk itu dibutuhkan peningkatan produksi kantung darah. Salah satu solusi yang dapat dilakukan adalah perancangan suatu sistem informasi geografis (GIS yang memudahkan pendonor untuk mendonorkan darahnya kembali dengan reminder donor darah dan membantu PMI mendapatkan kantung darah. Makalah ini membahas perancangan sistem reminder donor darah dengan menggunakan teknologi location based service. Kemudian untuk menguji sistem, dibuatkan sebuah prototype dengan hasil pengujian sistem menunjukkan bahwa sistem reminder donor darah dapat memudahkan pendonor dalam mendonorkan darahnya kembali sehingga memberikan motivasi bagi pendonor untuk lebih giat dalam mendonorkan darahnya. Sistem ini berpotensi meningkatkan produktivitas PMI dalam mengumpulkan kantong darah sehingga pemenuhan kebutuhan kantung darah masyarakat dapat meningkat yang pada akhirnya dapat menyelamatkan lebih banyak nyawa manusia khususnya di Indonesia. Kata kunci: donor darah, reminder, GIS, location based service.

Disrupt dit Mindset og få succes med Big Data

DEFF Research Database (Denmark)

Rydén, Pernille; Ringberg, Torsten; Østergaard Jacobsen, Per

Organisationer fokuserer i stigende grad på, hvordan de kan bruge Big Data strategisk. De investerer milliarder af kroner i denne ny teknologi, men værdien og afkastet viser sig tit at være begrænset. Sådanne udfordringer kan meget vel skyldes ledernes mindset, der begrænser hvordan organisationen...... bruger Big Data-teknologi til at styrke interaktionen og samspillet med kunder og andre interessenter. Det første skridt på vejen mod at få succes med Big Data er derfor at identificere og udfordre sit ledelsesmæssige mindset. I denne bog identificerer og diskuterer vi fire dominerende ledelsesmæssige...... mindset, der hver især fører til fire unikke Big Data strategier. Når ledere inden for samme team har forskellige mindset, kan det føre til manglende mental og organisatorisk alignment og problemer med at håndtere disruption. Da mindsets ofte er ubevidste, har vi udviklet en onlinetest, der hjælper dig og...

UJI COBA TEKNOLOGI BIOFILM KONSORSIUM BAKTERI PADA REAKTOR SEMIANAEROB-AEROB UNTUK PENGOLAHAN AIR LIMBAH DI INDUSTRI PENCELUPAN TEKSTIL SKALA RUMAH TANGGA

Directory of Open Access Journals (Sweden)

Dewa Ketut Sastrawidana

2013-04-01

Full Text Available Penelitian ini bertujuan untuk menganalisis efektifitas teknologi biofilm konsorsium bakteri pada  reaktor semianaerob-aerob ntuk mengolah air limbah pencelupan tekstil. Bakteri pada reaktor semianaerob terdiri dari  Aeromonas sp. Pseudomonas sp, dan Flavobacterium sp. sedangkan pada reaktor aerob terdiri dari Vibrio sp. Plesiomonas sp. dan Enterobacter sp. Perombakan proses pertumbuhan terlekat diawali dengan menumbuhkan konsorsium bakteri pada masing-masing reaktor selama 10  hari menggunakan pada batu vulkanik merah sebagai media pelekatan bakteri. Setelah terbentuk biofilm,selanjutnya digunakan untuk merombak limbah denagn waktu tinggal limbah 2 hari. Hasil penelitian menunjukkan teknologi biofilm cukup efektif diaplikasikan pada skala lapang menghasilkan efisiensi perombakan TSS, BOD dan COD secara berturut-turut sebesar 84,7%; 80,56% dan 90,40%. Uji toksisitas air limbah tekstil menggunakan ikan nila dengan waktu paparan 3 hari menunjukkan bahwa air limbah tekstil sebelum diolah berkatagori toksik ringan dengan nilai EC50 adalah 88,80% sedangkan setelah diolah dalam reaktor biofilm konsorsium bakteri sistem anaerob-aerob selama 2 hari menjadi katagori tidak toksik dengan nilai EC50 sebesar 101,64%. Dengan demikian, pengolahan limbah tektil dengan sistem kombinasi anaerob-aerob menghasilkan kualitas limbah dengan kriteria sudah memenuhi baku mutu untuk dibuang ke lingkungan.

Effect of uranium (VI) on the growth of yeast and influence of metabolism of yeast on adsorption of U (VI)

International Nuclear Information System (INIS)

Sakamoto, Fuminori; Ohnuki, Toshihiko; Kozai, Naofumi; Wakai, Eiichi; Francis, A.J.

2005-01-01

We have carried out the growth experiments of 3 strains of yeast in a medium containing uranium (VI) to elucidate the effect of U (VI) on the growth of microorganisms. Hansenula fabianii J640 grew in the liquid medium containing 0.1 mM U (VI) at lower rate than the control, but Saccharomyces cerevisiae did not grow under this condition. The H. fabianii J640 pre-cultured for 21 h in the liquid medium without U (VI) grew even after the exposure to 1 mM U (VI), but did not grow without pre-cultivation. For the pre-cultured H. fabianii J640, radioactivity of U in the medium was the same as the initial one for 110 h, and then gradually decreased. TEM-EDS analysis of H. fabianii J640 exposed to 1 mM U (VI) for 165 h showed accumulation of U (VI) on the cells. When H. fabianii J640 was not pre-cultured, radioactivity of U in the medium was lower than the initial one. These results indicated that U (VI) inhibits the growth of yeast, and that the adsorption of U (VI) by the cells depends on the metabolism of yeast. (author)

Preparation and properties of N-Phenylbutyrohydroxamic acid and N-p-Chlorophenylbutyrohydroxamic acid and their uses as extracting agents for Chromium (VI), Molybdenum (VI), Titanium (IV) and Uranium (VI)

Energy Technology Data Exchange (ETDEWEB)

Abu Elnour, Sawsan Hassan [Department of Chemistry, Faculty of Science, University of Khartoum, Khartoum (Sudan)

1993-05-01

Two lignads, N-phenylbutyrohydroxamic acid (1), N-p-chlorophenylbutyryl chloride with {beta} phenyl-hydroylamine and N-p-chlorophenylhydroxylamine, respectively. The acids prepared were identified and characterised through their reactions with Vanadiun (V) and iron (III), their melting points, infra-red spectra and nitrogen content. The extractive properties of these acids towards the metals Cr (VI), Mo (VI), Ti (IV) and U (VI) were examined at different PH values. The percentage of maximum extraction with the two acids was found to be as follows : for Cr (VI) at PH 1, (100%) for both acids, Mo (VI) at PH 2 (33.34%) with acid (I) and (16.67%) with acid (II) and U (VI) at PH 6 (72%) with acid (I) and (76%) with acid (II). The metal: Ligand complexes ratios were determined by using the continuous variation method, the ratio of the two ligands with four metals was found to be 1:2. Finally the suitability of the two acids for spectrophotometric determination of four metals was examined.(Author) 90 refs. , 24 tabs. , 24 figs

Preparation and properties of N-Phenylbutyrohydroxamic acid and N-p-Chlorophenylbutyrohydroxamic acid and their uses as extracting agents for Chromium (VI), Molybdenum (VI), Titanium (IV) and Uranium (VI)

International Nuclear Information System (INIS)

Abu Elnour, Sawsan Hassan

1993-05-01

Two lignads, N-phenylbutyrohydroxamic acid (1), N-p-chlorophenylbutyryl chloride with β phenyl-hydroylamine and N-p-chlorophenylhydroxylamine, respectively. The acids prepared were identified and characterised through their reactions with Vanadiun (V) and iron (III), their melting points, infra-red spectra and nitrogen content. The extractive properties of these acids towards the metals Cr (VI), Mo (VI), Ti (IV) and U (VI) were examined at different PH values. The percentage of maximum extraction with the two acids was found to be as follows : for Cr (VI) at PH 1, (100%) for both acids, Mo (VI) at PH 2 (33.34%) with acid (I) and (16.67%) with acid (II) and U (VI) at PH 6 (72%) with acid (I) and (76%) with acid (II). The metal: Ligand complexes ratios were determined by using the continuous variation method, the ratio of the two ligands with four metals was found to be 1:2. Finally the suitability of the two acids for spectrophotometric determination of four metals was examined.(Author)

Tingkat Kematangan Infrastruktur Teknologi Informasi pada Domain Acquire and Implement Menggunakan COBIT 4.1 (Studi Kasus: UPT Perpustakaan Universitas Pembangunan Nasional “VETERAN” Jawa Timur

Directory of Open Access Journals (Sweden)

Ronggo Alit

2017-07-01

Full Text Available Berdasarkan hasil wawancara UPT Perpustakaan kekurangan perangkat komputer dan masih menggunakan server milik UPT Telematika serta kecepatan akses wifi akan lambat jika banyak yang menggunakan sehingga perlu dilakukan penelitian ini yang bertujuan untuk mengetahui tingkat kematangan dan menghasilkan rekomendasi guna meningkatkan pengelolaan infrastruktur teknologi informasi. Penelitian dilakukan menggunakan COBIT Framework 4.1 tahap penelitian diawali dengan analisa data wawancara kemudian diidentifikasi IT goals, IT process, serta Control Objectives. Perhitungan maturity level untuk mengetahui gap antara kondisi sekarang dengan kondisi yang diharapkan dan rekomendasi digunakan untuk mengatasi gap tersebut. Dari hasil penelitian yang dilakukan diperoleh 4 IT Goals, 10 IT Processes dan 17 detailed control objectives. Karena pemilihan subdomain disesuaikan dengan masalah dan kebutuhan maka subdomain yang digunakan adalah PO3, PO7, AI3 dan AI5. Ditemukan gap sebesar 1.5 dan maturity level sebesar 2.5 sehingga berada pada level 3 artinya perpustakaan telah memiliki mekanisme dan prosedur yang jelas mengenai tata cara dan manajemen teknologi informasi.

Pengkajian Rakitan Teknologi Budidaya Kentang dan Strategi Pengembangannya : Studi Kasus di Wilayah Prima Tani Lahan Kering Dataran Tinggi Kabupaten Magetan

OpenAIRE

Santoso, Pudji; Yuniarti; Purnomo, Sudarmadi; Subandi

2009-01-01

Pengkajian Rakitan Teknologi Budidaya Kentang dan Strategi Pengembangannya : Studi Kasus di Wilayah Prima Tani Lahan Kering Dataran Tinggi Kabupaten Magetan. The assessment on improving the cultivation technology of potato as demonstration plot in farmer's land was done in Prima Tani area of Magetan regency in Genilangit village, during dry season on June – September 2007. Collecting data was done using farm record keeping method on the application of improving cultivation technology of potat...

The Dagger and The Shield: The Ballistic Missile Defence and Sino-US Strategic Relationship

Directory of Open Access Journals (Sweden)

Ristian Atriandi Supriyanto

2016-04-01

Full Text Available Menghadapi potensi ancaman serangan senjata rudal pemusnah massal dari rogue states, seperti Iran and Korea Utara, Amerika Serikat (AS merespon dengan mendirikan program Pertahanan Rudal Balistik (BMD untuk menembak jatuh rudal-rudal tersebut di angkasa. Akan tetapi, Republik Rakyat Cina (RRC menganggap program BMD AS itu tidak hanya bertujuan untuk menghadapi rogue states, namun juga RRC. RRC menilai rudal dan senjata nuklir sebagai "belati" yang telah berhasil menjamin stabilitas internasional melalui penciptaan hubungan saling gentar (mutual deterrence di antara kekuatan-kekuatan nuklir dunia. Sementara program BMD yang diibaratkan sebagai "perisai" dianggap hanya akan mendestabilisasi hubungan tersebut. Guna mengimbangi BMD AS, RRC akan meningkatkan jumlah dan kualitas rudal serta senjata nuklirnya hingga tetap kredibel dalam menjaga hubungan saling gentar dengan AS. Kondisi ini justru akan menciptakan lingkungan strategis internasional yang makin tidak stabil dan bahkan berpotensi memicu perlombaan senjata nuklir antara RRC dengan AS. Untuk mencegah kondisi tersebut, AS harus meyakinkan RRC bahwa program BMD hanya digunakan untuk menghadapi rogue states.

Different roles of ROS and Nrf2 in Cr(VI)-induced inflammatory responses in normal and Cr(VI)-transformed cells

Energy Technology Data Exchange (ETDEWEB)

Roy, Ram Vinod; Pratheeshkumar, Poyil; Son, Yong-Ok; Wang, Lei [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Department of Toxicology and Cancer Biology, College of Medicine, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Hitron, John Andrew [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Divya, Sasidharan Padmaja; Zhang, Zhuo [Department of Toxicology and Cancer Biology, College of Medicine, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Shi, Xianglin, E-mail: xshi5@email.uky.edu [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States)

2016-09-15

Hexavalent chromium (Cr(VI)) is classified as a human carcinogen. Cr(VI) has been associated with adenocarcinomas and squamous cell carcinoma of the lung. The present study shows that acute Cr(VI) treatment in human bronchial epithelial cells (BEAS-2B) increased inflammatory responses (TNF-α, COX-2, and NF-кB/p65) and expression of Nrf2. Cr(VI)-induced generation of reactive oxygen species (ROS) are responsible for increased inflammation. Despite the fact that Nrf2 is a master regulator of response to oxidative stress, silencing of Nrf2 in the acute Cr(VI) treatment had no effect on Cr(VI)-induced inflammation. In contrast, in Cr(VI)-transformed (CrT) cells, Nrf2 is constitutively activated. Knock-down of this protein resulted in decreased inflammation, while silencing of SOD2 and CAT had no effect in the expression of these inflammatory proteins. Results obtained from the knock-down of Nrf2 in CrT cells are very different from the results obtained in the acute Cr(VI) treatment. In BEAS-2B cells, knock-down of Nrf2 had no effect in the inflammation levels, while in CrT cells a decrease in the expression of inflammation markers was observed. These results indicate that before transformation, ROS plays a critical role while Nrf2 not in Cr(VI)-induced inflammation, whereas after transformation (CrT cells), Nrf2 is constitutively activated and this protein maintains inflammation while ROS not. Constitutively high levels of Nrf2 in CrT binds to the promoter regions of COX-2 and TNF-α, leading to increased inflammation. Collectively, our results demonstrate that before cell transformation ROS are important in Cr(VI)-induced inflammation and after transformation a constitutively high level of Nrf2 is important. - Highlights: • Cr(VI)-induced ROS increased inflammation, while Nrf2 had no effect. • In the CrT cells knock-down of Nrf2 resulted in decreased inflammation. • Mechanistic differences in regulating Cr(VI)-induced inflammation.

Kinetic investigations of quinoline oxidation by ferrate(VI).

Science.gov (United States)

Luo, Zhiyong; Li, Xueming; Zhai, Jun

2016-01-01

Quinoline is considered as one of the most toxic and carcinogenic compounds and is commonly found in industrial wastewaters, which require treatment before being discharged. Removal of quinoline by the use of an environmentally friendly oxidant, potassium ferrate(VI) (K2FeO4), was assessed by studying the kinetics of the oxidation of quinoline by ferrate(VI) (Fe(VI)) as a function of pH (8.53-10.53) and temperature (21-36°C) in this work. The reaction of quinoline with Fe(VI) was found to be first order in Fe(VI), half order in quinoline, and 1.5 order overall. The observed rate constant at 28°C decreased non-linearly from 0.5334 to 0.2365 M(-0.5) min(-1) with an increase in pH from 8.53 to 10.03. Considering the equilibria of Fe(VI) and quinoline, the reaction between quinoline and Fe(VI) contained two parallel reactions under the given pH conditions. The individual rate constants of these two reactions were determined. The results indicate that the protonated species of Fe(VI) reacts more quickly with quinoline than the deprotonated form of Fe(VI). The reaction activation energy Ea was obtained to be 51.44 kJ·mol(-1), and it was slightly lower than that of conventional chemical reaction. It reveals that the oxidation of quinoline by Fe(VI) is feasible in the routine water treatment.

Immunization with the conjugate vaccine Vi-CRM₁₉₇ against Salmonella typhi induces Vi-specific mucosal and systemic immune responses in mice.

Science.gov (United States)

Fiorino, Fabio; Ciabattini, Annalisa; Rondini, Simona; Pozzi, Gianni; Martin, Laura B; Medaglini, Donata

2012-09-21

Typhoid fever is a public health problem, especially among young children in developing countries. To address this need, a glycoconjugate vaccine Vi-CRM₁₉₇, composed of the polysaccharide antigen Vi covalently conjugated to the non-toxic mutant of diphtheria toxin CRM₁₉₇, is under development. Here, we assessed the antibody and cellular responses, both local and systemic, following subcutaneous injection of Vi-CRM₁₉₇. The glycoconjugate elicited Vi-specific serum IgG titers significantly higher than unconjugated Vi, with prevalence of IgG1 that persisted for at least 60 days after immunization. Vi-specific IgG, but not IgA, were present in intestinal washes. Lymphocytes proliferation after restimulation with Vi-CRM₁₉₇ was observed in spleen and mesenteric lymph nodes. These data confirm the immunogenicity of Vi-CRM₁₉₇ and demonstrate that the vaccine-specific antibody and cellular immune responses are present also in the intestinal tract, thus strengthening the suitability of Vi-CRM₁₉₇ as a promising candidate vaccine against Salmonella Typhi. Copyright © 2012 Elsevier Ltd. All rights reserved.

Electrochemical alkaline Fe(VI) water purification and remediation.

Science.gov (United States)

Licht, Stuart; Yu, Xingwen

2005-10-15

Fe(VI) is an unusual and strongly oxidizing form of iron, which provides a potentially less hazardous water-purifying agent than chlorine. A novel on-line electrochemical Fe(VI) water purification methodology is introduced. Fe(VI) addition had been a barrier to its effective use in water remediation, because solid Fe(VI) salts require complex (costly) syntheses steps and solutions of Fe(VI) decompose. Online electrochemical Fe(VI) water purification avoids these limitations, in which Fe(VI) is directly prepared in solution from an iron anode as the FeO42- ion, and is added to the contaminant stream. Added FeO42- decomposes, by oxidizing a wide range of water contaminants including sulfides (demonstrated in this study) and other sulfur-containing compounds, cyanides (demonstrated in this study), arsenic (demonstrated in this study), ammonia and other nitrogen-containing compounds (previously demonstrated), a wide range of organics (phenol demonstrated in this study), algae, and viruses (each previously demonstrated).

Electronic structure, fluorescence and photochemistry of the uranyl ion, and comparison with octahedral uranium (VI), ruthenyl (VI), rhenium (V) and osmium (VI) complexes

Energy Technology Data Exchange (ETDEWEB)

Joergensen, C K [Geneva Univ. (Switzerland)

1977-01-01

The highly anisotropic uranyl complexes (with very short U-O distances and very long distances to the ligating atoms in the equatorial plane) are compared with trans-dioxo complexes of 4d/sup 2/Ru(VI) and 5d/sup 2/Re(V) and Os(VI). A major difference is the low-lying empty 5f orbitals, and the first excited state is highly oxidizing, and sufficiently long-lived to abstract hydrogen atoms from most organic molecules. It is argued that even the low concentrations of uranyl carbonate present in sea water is excited by solar radiation roughly every 10 minutes. Octahedral U(VI)O/sub 6/ in perovskites and UF/sub 6/ are also discussed, as well as trans-lawrencium chemistry.

Peningkatan Kesejahteraan Perajin Batik Tulis Melalui Penerapan Teknologi Pemungutan Zat Warna Alam

Directory of Open Access Journals (Sweden)

Prima Astuti Handayani

2013-02-01

Full Text Available Seiring kemajuan teknologi zat warna alam tergeser oleh keberadaan zat warna sintetis. Penggunaan zat warna alam masih tetap dijaga keberadaannya khususnya pada pembatikan. Kain batik yang menggunakan zat warna alam memiliki nilai jual yang tinggi karena memiliki nilai seni dan warna khas, tidak bersifat karsiogenik, ramah lingkungan serta berkesan etnik dan eksklusif. Zat warna alam coklat untuk pewarnaan batik dapat diperoleh dari kulit soga tingi melalui proses ekstraksi dengan pelarut etanol. Tujuan spesifik dari kegiatan pengabdian kepada masyarakat adalah perajin batik Desa Pandan Kabupaten Rembang mampu membuat zat warna batik dari alam, untuk memenuhi kebutuhan dirinya sendiri, sehingga diharapkan dapat meningkatkan pendapatan keluarga. Metode yang dilakukan meliputi metode ceramah mengenai pembuatan zat warna; metode praktek tentang proses pembuatan zat warna dari kulit soga tingi; metode tanya jawab untuk mengetahui sejauh mana peserta mampu menerima atau terlibat dalam kegiatan, dan evaluasi untuk memperoleh gambaran penafsiran dan analisis untuk memperoleh simpulan dari semua kegiatan pengabdian kepada masyarakat yang sudah dilaksanakan.

REMASTERING LIVE USB UNTUK LAMP PADA FAKULTAS SAINS DAN TEKNOLOGI PALEMBANG

Directory of Open Access Journals (Sweden)

Klaudius Jevanda B.S.

2015-11-01

Full Text Available ABSTRAK Penelitian ini bertujuan untuk membuat distribusi Linux bernama Lubuntu yang memfokuskan diri pada desktop yang ringan serta ditujukan untuk menjadi lingkungan web server yang free dalam bentuk live USB. Dimana, penelitian ini menjelaskan tentang desain dan implementasi dari distribusi Linux Lubuntu itu sendiri yang nantinya bisa terus diperbaiki, disempurnakan dan dimungkinkan untuk dimodifikasi serta dipelajari oleh pihak lain. Lubuntu dikembangkan dengan memodifikasi dari Linux Lubuntu 14.04 dari tahap penambahan program, penghapusan program dan konfigurasi sampai pada tahap pembuatan Live USB untuk LAMP (Linux Apache Mysql PHP menggunakan metode remastering. Hasil dari penelitian ini berupa Live USB yang berisi tool untuk lingkungan web server. Tool utama dalam Live USB diantaranya adalah phpmyadmin, gimp, inkscape, dan bluefish. Keluaran penelitian ini, diharapkan bisa digunakan sebagai sistem operasi dan dikhususkan dalam lingkungan web server yang nyaman untuk dipergunakan dalam proses belajar mengajar pada matakuliah sistem operasi, pemrograman basis web I, dan pemrograman basis web II di Fakultas Sains dan Teknologi Universitas Katolik Musi Charitas palembang. Kata kunci: linux, web server, LAMP, remastering, live usb.

Læring mellem elever

DEFF Research Database (Denmark)

Davidsen, Jacob; Georgsen, Marianne

I denne rapport tilbyder vi et indblik i det gennemførte projekt, og forfatterne har valgt nogle forhold ud, som belyses og diskuteres, mens andre ikke berøres eller diskuteres nævneværdigt i denne rapport. Det skyldes blandt andet projektets mange facetter, som dækker både læring, teknologi, pæd...

Biosorption of Cr(VI) by coconut coir: Spectroscopic investigation on the reaction mechanism of Cr(VI) with lignocellulosic material

International Nuclear Information System (INIS)

Shen, Ying-Shuian; Wang, Shan-Li; Huang, Shiuh-Tsuen; Tzou, Yu-Min; Huang, Jang-Hung

2010-01-01

In this study, the removal mechanism of Cr(VI) from water by coconut coir (CC) was investigated using X-ray photoelectron spectroscopy (XPS), Cr K-edge X-ray absorption near edge structure (XANES) and FTIR spectroscopy. The results showed that, upon reaction with CC at pH 3, Cr(VI) was reduced to Cr(III), which was either bound to CC or released back into solution. As revealed by the FTIR spectra of CC before and after reacting with Cr(VI), the phenolic methoxyl and hydroxyl groups of lignin in CC are the dominant drivers of Cr(VI) reduction, giving rise to carbonyl and carboxyl groups on CC. These functional groups can subsequently provide binding sites for Cr(III) resulting from Cr(VI) reduction. In conjunction with forming complexes with carbonyl and carboxyl groups, the formation of Cr(III) hydroxide precipitate could also readily occur as revealed by the linear combination fitting of the Cr K-edge XANES spectrum using a set of reference compounds. The phenolic groups in lignin are responsible for initiating Cr(VI) reduction, so lignocellulosic materials containing a higher amount of phenolic groups are expected to be more effective scavengers for removal of Cr(VI) from the environment.

Biosorption of Cr(VI) by coconut coir: Spectroscopic investigation on the reaction mechanism of Cr(VI) with lignocellulosic material

Energy Technology Data Exchange (ETDEWEB)

Shen, Ying-Shuian [Department of Soil and Environmental Sciences, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China); Wang, Shan-Li, E-mail: slwang@nchu.edu.tw [Department of Soil and Environmental Sciences, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China); Huang, Shiuh-Tsuen [Department of Soil and Environmental Sciences, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China); Department of Science Application and Dissemination, National Taichung University, Taichung, Taiwan (China); Tzou, Yu-Min; Huang, Jang-Hung [Department of Soil and Environmental Sciences, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan (China)

2010-07-15

In this study, the removal mechanism of Cr(VI) from water by coconut coir (CC) was investigated using X-ray photoelectron spectroscopy (XPS), Cr K-edge X-ray absorption near edge structure (XANES) and FTIR spectroscopy. The results showed that, upon reaction with CC at pH 3, Cr(VI) was reduced to Cr(III), which was either bound to CC or released back into solution. As revealed by the FTIR spectra of CC before and after reacting with Cr(VI), the phenolic methoxyl and hydroxyl groups of lignin in CC are the dominant drivers of Cr(VI) reduction, giving rise to carbonyl and carboxyl groups on CC. These functional groups can subsequently provide binding sites for Cr(III) resulting from Cr(VI) reduction. In conjunction with forming complexes with carbonyl and carboxyl groups, the formation of Cr(III) hydroxide precipitate could also readily occur as revealed by the linear combination fitting of the Cr K-edge XANES spectrum using a set of reference compounds. The phenolic groups in lignin are responsible for initiating Cr(VI) reduction, so lignocellulosic materials containing a higher amount of phenolic groups are expected to be more effective scavengers for removal of Cr(VI) from the environment.

Biosorption of Cr(VI) by coconut coir: spectroscopic investigation on the reaction mechanism of Cr(VI) with lignocellulosic material.

Science.gov (United States)

Shen, Ying-Shuian; Wang, Shan-Li; Huang, Shiuh-Tsuen; Tzou, Yu-Min; Huang, Jang-Hung

2010-07-15

In this study, the removal mechanism of Cr(VI) from water by coconut coir (CC) was investigated using X-ray photoelectron spectroscopy (XPS), Cr K-edge X-ray absorption near edge structure (XANES) and FTIR spectroscopy. The results showed that, upon reaction with CC at pH 3, Cr(VI) was reduced to Cr(III), which was either bound to CC or released back into solution. As revealed by the FTIR spectra of CC before and after reacting with Cr(VI), the phenolic methoxyl and hydroxyl groups of lignin in CC are the dominant drivers of Cr(VI) reduction, giving rise to carbonyl and carboxyl groups on CC. These functional groups can subsequently provide binding sites for Cr(III) resulting from Cr(VI) reduction. In conjunction with forming complexes with carbonyl and carboxyl groups, the formation of Cr(III) hydroxide precipitate could also readily occur as revealed by the linear combination fitting of the Cr K-edge XANES spectrum using a set of reference compounds. The phenolic groups in lignin are responsible for initiating Cr(VI) reduction, so lignocellulosic materials containing a higher amount of phenolic groups are expected to be more effective scavengers for removal of Cr(VI) from the environment. 2010 Elsevier B.V. All rights reserved.

Isolation of a star-shaped uranium(V/VI) cluster from the anaerobic photochemical reduction of uranyl(VI)

International Nuclear Information System (INIS)

Chatelain, Lucile; White, Sarah; Scopelliti, Rosario; Mazzanti, Marinella

2016-01-01

Actinide oxo clusters are an important class of compounds due to their impact on actinide migration in the environment. The photolytic reduction of uranyl(VI) has potential application in catalysis and spent nuclear fuel reprocessing, but the intermediate species involved in this reduction have not yet been elucidated. Here we show that the photolysis of partially hydrated uranyl(VI) in anaerobic conditions leads to the reduction of uranyl(VI), and to the incorporation of the resulting U V species into the stable mixed-valent star-shaped U VI /U V oxo cluster [U(UO 2 ) 5 (μ 3 -O) 5 (PhCOO) 5 (Py) 7 ]. This cluster is only the second example of a U VI /U V cluster and the first one associating uranyl groups to a non-uranyl(V) center. The U V center in 1 is stable, while the reaction of uranyl(V) iodide with potassium benzoate leads to immediate disproportionation and formation of the U 12 IV U 4 V O 24 cluster {[K(Py) 2 ] 2 [K(Py)] 2 [U 16 O 24 (PhCOO) 24 (Py) 2 ]}.

STUDI KASUS PEMANFAATAN E-LEARNING SEBAGAI SALAH SATU SARANA YANG MENDUKUNG PEMBELAJARAN DI FAKULTAS TEKNOLOGI INFORMASI DAN KOMUNIKASI UNIVERSITAS SEMARANG

Directory of Open Access Journals (Sweden)

Maya Rini Handayani

2011-01-01

Full Text Available Seiring dengan perkembangan Teknologi Informasi (TI yang semakin pesat, kebutuhan akan suatu konsep dan mekanisme belajar mengajar (pendidikan berbasis TI menjadi tidak terelakkan lagi. Konsep yang kemudian terkenal dengan sebutan e-Learning ini membawa pengaruh terjadinya proses transformasi pendidikan konvensional ke dalam bentuk digital, baik secara isi (contents dan sistemnya. Sistem e-Learning mutlak diperlukan untuk mengantisipasi perkembangan jaman dengan dukungan Teknologi Informasi dimana semua menuju ke era digital, baik mekanisme maupun konten. Pengembangan sistem e-Learning harus didahului dengan melakukan analisa terhadap kebutuhan dari pengguna (user needs. Sesuai dengan paradigma rekayasa sistem dan perangkat lunak, kebutuhan dari pengguna ini memiliki kedudukan tertinggi, dan merupakan dasar kreasi dan kerja pengembang. Agar penelitian ini dapat memberikan hasil yang baik, maka penulisan laporannya menggunakan berbagai macam data, keterangan data, serta informasi penting yang diperoleh dari berbagai sumber, didasarkan pada (1 data primer, yaitu data yang diperoleh secara langsung dari obyek penelitian ( dosen dan mahasiswa , (2 data sekunder, yaitu data yang diperoleh dari buku-buku, literatur sebagai pelengkap dalam penyusunan laporan penelitian ini. Metode Studi Pustaka, yaitu metode pengumpulan data melalui pemahaman literatur maupun buku dan juga browsing internet sebagai acuan untuk menentukan landasan teori. Metode angket / kuesioner, yaitu pengumpulan data dengan membagikan kuesioner kepada para dosen dan mahasiswa di lingkungan FTIK USM

Comparison of U(VI) adsorption onto nanoscale zero-valent iron and red soil in the presence of U(VI)–CO_3/Ca–U(VI)–CO_3 complexes

International Nuclear Information System (INIS)

Zhang, Zhibin; Liu, Jun; Cao, Xiaohong; Luo, Xuanping; Hua, Rong; Liu, Yan; Yu, Xiaofeng; He, Likai

2015-01-01

Highlights: • NZVI can be used for adsorbing U(VI)–CO_3 complexes. • Use of NZVI is feasible for remediation of uranium-contaminated soils. • The mechanism of U(VI)–CO_3 complexes adsorbing onto NZVI has been explained. - Abstract: The influence of U(VI)–CO_3 and Ca–U(VI)–CO_3 complexes on U(VI) adsorption onto red soil and nanoscale zero-valent iron (NZVI) was investigated using batch adsorption and fixed-bed column experiments to simulate the feasibility of NZVI as the reactive medium in permeable- reactive barriers (PRB) for in situ remediation of uranium-contaminated red soils. The adsorption capacity (q_e) and distribution constant (K_d) of NZVI and red soil decreased with increasing pH, dissolved carbonate and calcium concentrations, but the q_e and K_d values of NZVI were 5–10 times higher than those of red soil. The breakthrough pore volume (PV) values increased with the decrease of pH, dissolved carbonate and calcium concentration; however, the breakthrough PV values of the PRB column filled with 5% NZVI were 2.0–3.5 times higher than the 100% red soil column. The U(VI)–CO_3 complexes adsorbed onto the surface of red soil/NZVI (≡SOH) to form SO–UO_2CO_3"− or SO–UO_2 (CO_3)_2"3"−. XPS and XRD analysis further confirmed the reduction of U(VI) to U(IV) and the formation of FeOOH on NZVI surfaces. The findings of this study are significant to the remediation of uranium-contaminated red soils and the consideration of practical U(VI) species in the natural environment.

Numeriske tåger

DEFF Research Database (Denmark)

Knakkergaard, Martin

2015-01-01

med dette talpar omtyder vi alt, hvad der lader sig omtyde, til tabeller i en ustoppelig bevægelse, som efterlader det omtydede til glemsel og nostalgi. Afhængig af hvordan vi anskuer disse tabeller, i det rene Aristoteliske perspektiv eller i Heideggers mere spekulative optik, er det enten causa...... finalis eller causa efficiens, som tabellerne fremstiller for os, men hvad blev der af causa materialis og causa formalis undervejs? Og at producere betyder netop at stille frem, at fremstille - dette vægter ifølge sagens natur det 'stillads' - den teknik eller teknologi - gennem hvilket noget stilles...

Reactivity of nitrido complexes of ruthenium(VI), osmium(VI), and manganese(V) bearing Schiff base and simple anionic ligands.

Science.gov (United States)

Man, Wai-Lun; Lam, William W Y; Lau, Tai-Chu

2014-02-18

Nitrido complexes (M≡N) may be key intermediates in chemical and biological nitrogen fixation and serve as useful reagents for nitrogenation of organic compounds. Osmium(VI) nitrido complexes bearing 2,2':6',2″-terpyridine (terpy), 2,2'-bipyridine (bpy), or hydrotris(1-pyrazolyl)borate anion (Tp) ligands are highly electrophilic: they can react with a variety of nucleophiles to generate novel osmium(IV)/(V) complexes. This Account describes our recent results studying the reactivity of nitridocomplexes of ruthenium(VI), osmium(VI), and manganese(V) that bear Schiff bases and other simple anionic ligands. We demonstrate that these nitrido complexes exhibit rich chemical reactivity. They react with various nucleophiles, activate C-H bonds, undergo N···N coupling, catalyze the oxidation of organic compounds, and show anticancer activities. Ruthenium(VI) nitrido complexes bearing Schiff base ligands, such as [Ru(VI)(N)(salchda)(CH3OH)](+) (salchda = N,N'-bis(salicylidene)o-cyclohexyldiamine dianion), are highly electrophilic. This complex reacts readily at ambient conditions with a variety of nucleophiles at rates that are much faster than similar reactions using Os(VI)≡N. This complex also carries out unique reactions, including the direct aziridination of alkenes, C-H bond activation of alkanes and C-N bond cleavage of anilines. The addition of ligands such as pyridine can enhance the reactivity of [Ru(VI)(N)(salchda)(CH3OH)](+). Therefore researchers can tune the reactivity of Ru≡N by adding a ligand L trans to nitride: L-Ru≡N. Moreover, the addition of various nucleophiles (Nu) to Ru(VI)≡N initially generate the ruthenium(IV) imido species Ru(IV)-N(Nu), a new class of hydrogen-atom transfer (HAT) reagents. Nucleophiles also readily add to coordinated Schiff base ligands in Os(VI)≡N and Ru(VI)≡N complexes. These additions are often stereospecific, suggesting that the nitrido ligand has a directing effect on the incoming nucleophile. M≡N is also

Mechanisms of chromium (VI)-induced apoptosis in anterior pituitary cells.

Science.gov (United States)

Quinteros, Fernanda A; Machiavelli, Leticia I; Miler, Eliana A; Cabilla, Jimena P; Duvilanski, Beatriz H

2008-07-30

Hexavalent chromium (Cr (VI)) is a highly toxic metal. Exposure to Cr (VI) compounds may affect reproductive functions. Due to the importance of anterior pituitary hormones on reproductive physiology we have studied the effects of Cr (VI) on anterior pituitary. We previously demonstrated that, after in vivo Cr (VI) administration, Cr accumulates in the pituitary gland and affects prolactin secretion. In vitro, Cr (VI) causes apoptosis in anterior pituitary cells due to oxidative stress generation. To better understand the mechanisms involved in Cr (VI)-induced apoptosis we studied: (a) whether Cr (VI) affects the intracellular antioxidant response and (b) which of the apoptotic factors participates in Cr (VI) effect. Our results show that Cr (VI) treatment induces a decrease in catalase and glutathione peroxidase (GPx) activity but does not modify glutathione reductase (GR) activity. Cr (VI) exposure causes an increase of GSH levels. p53 and Bax mRNA are also upregulated by the metal. Pifithrin alpha, a p53 transcriptional inhibitor, increases Cr (VI) cytotoxicity, suggesting a role of p53 as a survival molecule. The antioxidant N-acetyl-cysteine (NAC) could prevent Bax mRNA increase and caspase 3 activation, confirming that Cr (VI)-induced apoptosis involves oxidative stress generation.

Emissions of chromium (VI) from arc welding.

Science.gov (United States)

Heung, William; Yun, Myoung-Jin; Chang, Daniel P Y; Green, Peter G; Halm, Chris

2007-02-01

The presence of Cr in the +6 oxidation state (Cr[VI]) is still observed in ambient air samples in California despite steps taken to reduce emissions from plating operations. One known source of emission of Cr(VI) is welding, especially with high Cr-content materials, such as stainless steels. An experimental effort was undertaken to expand and update Cr(VI) emission factors by conducting tests on four types of arc-welding operations: gas-metal arc welding (GMAW), shielded metal arc welding (SMAW), fluxcore arc welding, and pulsed GMAW. Standard American Welding Society hood results were compared with a total enclosure method that permitted isokinetic sampling for particle size-cut measurement, as well as total collection of the aerosol. The fraction of Cr(VI) emitted per unit mass of Cr electrode consumed was determined. Consistent with AP-42 data, initial results indicate that a significant fraction of the total Cr in the aerosol is in the +6 oxidation state. The fraction of Cr(VI) and total aerosol mass produced by the different arc welding methods varies with the type of welding process used. Self-shielded electrodes that do not use a shield gas, for example, SMAW, produce greater amounts of Cr(VI) per unit mass of electrode consumed. The formation of Cr(VI) from standard electrode wires used for welding mild steel was below the method detection limit after eliminating an artifact in the analytical method used.

Vi-da: vitiligo diagnostic assistance mobile application

Science.gov (United States)

Nugraha, G. A.; Nurhudatiana, A.; Bahana, R.

2018-03-01

Vitiligo is a skin disorder in which white patches of depigmentation appear on different parts of the body. Usually, patients come to hospitals or clinics to have their vitiligo conditions assessed. This can be very tiring to the patients, as vitiligo treatments usually take a relatively long period of time, which can range from months to years. To address this challenge, we present in this paper a prototype of an Android-based mobile application called Vi-DA, which stands for Vitiligo Diagnostic Assistance. Vi-DA consists of three subsystems, which are user sign-up subsystem, camera and image analysis subsystem, and progress report subsystem. The mobile application was developed in Java programming language and uses MySQL as the database system. Vi-DA adopts a vitiligo segmentation algorithm to segment input image into normal skin area, vitiligo skin area, and non-skin area. Results showed that Vi-DA gave comparable results to the previous system implemented in Matlab. User acceptance testing results also showed that all respondents agreed on the usefulness of the system and agreed to use Vi-DA again in the future. Vi-DA benefits both dermatologists and patients as not only a computer-aided diagnosis (CAD) tool but also as a smart application that can be used for self-assessment at home.

ViA: a perceptual visualization assistant

Science.gov (United States)

Healey, Chris G.; St. Amant, Robert; Elhaddad, Mahmoud S.

2000-05-01

This paper describes an automated visualized assistant called ViA. ViA is designed to help users construct perceptually optical visualizations to represent, explore, and analyze large, complex, multidimensional datasets. We have approached this problem by studying what is known about the control of human visual attention. By harnessing the low-level human visual system, we can support our dual goals of rapid and accurate visualization. Perceptual guidelines that we have built using psychophysical experiments form the basis for ViA. ViA uses modified mixed-initiative planning algorithms from artificial intelligence to search of perceptually optical data attribute to visual feature mappings. Our perceptual guidelines are integrated into evaluation engines that provide evaluation weights for a given data-feature mapping, and hints on how that mapping might be improved. ViA begins by asking users a set of simple questions about their dataset and the analysis tasks they want to perform. Answers to these questions are used in combination with the evaluation engines to identify and intelligently pursue promising data-feature mappings. The result is an automatically-generated set of mappings that are perceptually salient, but that also respect the context of the dataset and users' preferences about how they want to visualize their data.

PENGEMBANGAN PROTOTIPE EGG BOILER SEBAGAI MEDIA PEMBELAJARAN PRAKARYA DAN KEWIRAUSAHAAN UNTUK MATERI TEKNOLOGI TEPAT GUNA KELAS XI MIA SMA NEGERI 4 SINGARAJA TAHUN AJARAN 2016/2017

Directory of Open Access Journals (Sweden)

Indra Kusuma Harta

2017-07-01

Full Text Available Penelitian ini bertujuan untuk mengembangkan Prototipe Egg Boiler (Pengkukus Telur Otomatis sebagai media pembelajaran untuk mata pelajaran Prakarya dan Kewirausahaan pada materi Teknologi Tepat Guna di Kelas XI MIA SMA Negeri 4 Singaraja. Penelitian ini dilakukan dengan menggunakan metode Penelitian dan Pengembangan dalam bidang pendidikan. Hasil uji validasi ahli media memperoleh skor sebesar 0,75 dalam kategori tinggi. Uji validasi isi dengan nilai sebesar 0,81 dalam kategori sangat tinggi.  Sedangkan hasil uji coba perorangan dengan nilai sebesar 0.93, uji coba kelompok kecil dengan nilai sebesar 0.71, dan uji coba lapangan dengan nilai sebesar 0.82. Pada uji coba lapangan juga dilakukan dengan menganalisis nilai dari kegiatan praktikum, nilai yang diperoleh 87.4 dikategorikan dengan hasil belajar tinggi. Dari hasil nilai pre-test dan post-test tersebut secara keseluruhan mengalami peningkatan. Sehingga Pototipe Egg Boiler yang telah dikembangkan sangat membantu siswa dalam memahami materi dan praktikum mata pelajaran Prakarya dan Kewirausahaan untuk materi Teknologi Tepat Guna di Kelas XI MIA SMA Negeri 4 Singaraja.

Comparison of U(VI) adsorption onto nanoscale zero-valent iron and red soil in the presence of U(VI)–CO{sub 3}/Ca–U(VI)–CO{sub 3} complexes

Energy Technology Data Exchange (ETDEWEB)

Zhang, Zhibin [Key Laboratory of Radioactive Geology and Exploration Technology Fundamental Science for National Defense, East China Institute of Technology, Nanchang 330013 (China); State Key Laboratory Breeding Base of Nuclear Resources and Environment (East China Institute of Technology), Ministry of Education, Nanchang 330013 (China); Chemistry, Biological and Materials Sciences Department, East China Institute of Technology, Nanchang 330013 (China); Liu, Jun [State Key Laboratory Breeding Base of Nuclear Resources and Environment (East China Institute of Technology), Ministry of Education, Nanchang 330013 (China); Cao, Xiaohong, E-mail: xhcao@ecit.cn [Key Laboratory of Radioactive Geology and Exploration Technology Fundamental Science for National Defense, East China Institute of Technology, Nanchang 330013 (China); State Key Laboratory Breeding Base of Nuclear Resources and Environment (East China Institute of Technology), Ministry of Education, Nanchang 330013 (China); Chemistry, Biological and Materials Sciences Department, East China Institute of Technology, Nanchang 330013 (China); Luo, Xuanping [Chemistry, Biological and Materials Sciences Department, East China Institute of Technology, Nanchang 330013 (China); Hua, Rong; Liu, Yan [Key Laboratory of Radioactive Geology and Exploration Technology Fundamental Science for National Defense, East China Institute of Technology, Nanchang 330013 (China); State Key Laboratory Breeding Base of Nuclear Resources and Environment (East China Institute of Technology), Ministry of Education, Nanchang 330013 (China); Chemistry, Biological and Materials Sciences Department, East China Institute of Technology, Nanchang 330013 (China); Yu, Xiaofeng; He, Likai [Chemistry, Biological and Materials Sciences Department, East China Institute of Technology, Nanchang 330013 (China); and others

2015-12-30

Highlights: • NZVI can be used for adsorbing U(VI)–CO{sub 3} complexes. • Use of NZVI is feasible for remediation of uranium-contaminated soils. • The mechanism of U(VI)–CO{sub 3} complexes adsorbing onto NZVI has been explained. - Abstract: The influence of U(VI)–CO{sub 3} and Ca–U(VI)–CO{sub 3} complexes on U(VI) adsorption onto red soil and nanoscale zero-valent iron (NZVI) was investigated using batch adsorption and fixed-bed column experiments to simulate the feasibility of NZVI as the reactive medium in permeable- reactive barriers (PRB) for in situ remediation of uranium-contaminated red soils. The adsorption capacity (q{sub e}) and distribution constant (K{sub d}) of NZVI and red soil decreased with increasing pH, dissolved carbonate and calcium concentrations, but the q{sub e} and K{sub d} values of NZVI were 5–10 times higher than those of red soil. The breakthrough pore volume (PV) values increased with the decrease of pH, dissolved carbonate and calcium concentration; however, the breakthrough PV values of the PRB column filled with 5% NZVI were 2.0–3.5 times higher than the 100% red soil column. The U(VI)–CO{sub 3} complexes adsorbed onto the surface of red soil/NZVI (≡SOH) to form SO–UO{sub 2}CO{sub 3}{sup −} or SO–UO{sub 2} (CO{sub 3}){sub 2}{sup 3−}. XPS and XRD analysis further confirmed the reduction of U(VI) to U(IV) and the formation of FeOOH on NZVI surfaces. The findings of this study are significant to the remediation of uranium-contaminated red soils and the consideration of practical U(VI) species in the natural environment.

Study of new U(VI) and Pu(VI) coprecipitation methods for the preparation of (U,Pu)O2

International Nuclear Information System (INIS)

Sanoit, J. de.

1990-01-01

Two U(VI) and Pu(VI) coprecipitation methods have been studied, for the definition of new processes to prepare (U,Pu)O 2 mixed oxides suitable for making MoX fuels or fast breeder reactor fuels. The first system is based on the coprecipitation of a new U(VI), Pu(VI) compound; ammonium uranoplutonate, where as a second system is related to the precipitation of uranyl plutonyl monocarbonate. Experimental conditions to optimize the precipitation and the filtration steps of these two systems have been determined. After calcination under reducing conditions, the mixed oxides obtained are characterized according to different techniques: granulometry, thermogravimetry, solubility in boiling HNO 3 solutions. The properties of such oxides are excellent. The possible processes for preparing (U, Pu)O 2 using these new routes are compared with those actually exploited [fr

Cr(VI) removal from aqueous solution by dried activated sludge biomass

International Nuclear Information System (INIS)

Wu Jun; Zhang Hua; He Pinjing; Yao Qian; Shao Liming

2010-01-01

Batch experiments were conducted to remove Cr(VI) from aqueous solution using activated sludge biomass. The effects of acid pretreatment of the biomass, initial pH, biomass and Cr(VI) concentrations on Cr(VI) removal efficiency were investigated. Proton consumption during the removal process and the reducing capacity of sludge biomass were studied. The results show that acid pretreatment could significantly improve Cr(VI) removal efficiency and increase Cr(VI) reducing capacity by 20.4%. Cr(VI) removal was remarkably pH-dependent; lower pH (pH = 1, 2) facilitated Cr(VI) reduction while higher pH (pH = 3, 4) favored sorption of the converted Cr(III). Lower Cr(VI) concentration as well as higher biomass concentration could accelerate Cr(VI) removal. Cr(VI) reduction was not the only reason for proton consumption in the removal process. Pseudo-second-order adsorption kinetic model could successfully simulate Cr(VI) removal except under higher pH conditions (pH = 3, 4).

Behaviour of chromium(VI) in stormwater soil infiltration systems

DEFF Research Database (Denmark)

Cederkvist, Karin; Ingvertsen, Simon T.; Jensen, Marina B.

2013-01-01

mm in 2 h) and extreme (100 mm in 3 h) rain events. The objectives were to understand the behaviour of the anionic and toxic Cr(VI) in soil at neutral pH and to asses treatment efficiency towards Cr(VI). During normal rain events Cr(VI) was largely retained (more than 50, even though pH was neutral......The ability of stormwater infiltration systems to retain Cr(VI) was tested by applying a synthetic stormwater runoff solution with a neutral pH and high Cr(VI) concentrations to four intact soil columns excavated from two roadside infiltration swales in Germany. Inlet flow rates mimicked normal (10......, while under extreme rain events approximately 20% of Cr(VI) was retained. In both cases effluent concentrations of Cr(VI) would exceed the threshold value of 3.4 mu g/L if the infiltrated water were introduced to freshwater environments. More knowledge on the composition of the stormwater runoff...

Isolation of a star-shaped uranium(V/VI) cluster from the anaerobic photochemical reduction of uranyl(VI)

Energy Technology Data Exchange (ETDEWEB)

Chatelain, Lucile; White, Sarah; Scopelliti, Rosario; Mazzanti, Marinella [Ecole Polytechnique Federale de Lausanne (EPFL) (Switzerland). Inst. de Sciences et Ingenierie Chimiques

2016-11-07

Actinide oxo clusters are an important class of compounds due to their impact on actinide migration in the environment. The photolytic reduction of uranyl(VI) has potential application in catalysis and spent nuclear fuel reprocessing, but the intermediate species involved in this reduction have not yet been elucidated. Here we show that the photolysis of partially hydrated uranyl(VI) in anaerobic conditions leads to the reduction of uranyl(VI), and to the incorporation of the resulting U{sup V} species into the stable mixed-valent star-shaped U{sup VI}/U{sup V} oxo cluster [U(UO{sub 2}){sub 5}(μ{sub 3}-O){sub 5}(PhCOO){sub 5}(Py){sub 7}]. This cluster is only the second example of a U{sup VI}/U{sup V} cluster and the first one associating uranyl groups to a non-uranyl(V) center. The U{sup V} center in 1 is stable, while the reaction of uranyl(V) iodide with potassium benzoate leads to immediate disproportionation and formation of the U{sub 12}{sup IV}U{sub 4}{sup V}O{sub 24} cluster {[K(Py)_2]_2[K(Py)]_2[U_1_6O_2_4(PhCOO)_2_4(Py)_2]}.

Aplikasi Pengenalan Ikan Hias Predator Air Tawar Menggunakan Teknologi Augmented Reality Berbasis Android

Directory of Open Access Journals (Sweden)

Jimmy Moedjahedy

2017-07-01

Full Text Available Penggemar dan komunitas hobi ikan hias predator di Manado makin berkembang dan orang yang ingin membelinya pun semakin bertambah. Berdasarkan pengamatan peneliti dibeberapa toko yang menjual ikan hias, pengenalan tentang ikan hias predator masih sangat kurang bahkan ditempat penjualan masih ada yang belum memiliki katalog tentang jenis ikan hias predator. Berdasarkan latar belakang tersebut, peneliti membuat aplikasi pengenalan ikan hias predator dengan menggunakan teknologi augmented reality berbasia android dimana pengguna dapat memanfaatkan smartphone mereka untuk melihat jenis dan info tentang ikan hias yang akan mereka beli dengan jelas dan atraktif. Metode rekayasa perangkat lunak yang digunakan adalah metode spiral karena metode ini menawarkan pendekatan yang lebih baik untuk membuat suatu program dengan cepat dan bertahap. Hasil dari penelitian ini adalah aplikasi android yang dapat menunjukan 9 jenis ikan hias predator dalam bentuk 3D yang dapat dilihat dari 4 sisi dan 6 jenis ikan lainnya dalam bentuk gambar serta informasi tertulis tentang ikan yang akan dipelihara.   Kata kunci : Augemented Reality, 3D, Android

Microbial Precipitation of Cr(III)-Hydroxide and Se(0) Nanoparticles During Anoxic Bioreduction of Cr(VI)- and Se(VI)-Contaminated Water.

Science.gov (United States)

Kim, Yumi; Oh, Jong-Min; Roh, Yul

2017-04-01

This study examined the microbial precipitations of Cr(III)-hydroxide and Se(0) nanoparticles during anoxic bioreductions of Cr(VI) and Se(VI) using metal-reducing bacteria enriched from groundwater. Metal-reducing bacteria enriched from groundwater at the Korea Atomic Energy Research Institute (KAERI) Underground Research Tunnel (KURT), Daejeon, S. Korea were used. Metal reduction and precipitation experiments with the metal-reducing bacteria were conducted using Cr(VI)- and Se(VI)-contaminated water and glucose as a carbon source under an anaerobic environment at room temperature. XRD, SEM-EDX, and TEM-EDX analyses were used to characterize the mineralogy, crystal structure, chemistry, shape, and size distribution of the precipitates. The metal-reducing bacteria reduced Cr(VI) of potassium chromate (K₂CrO₄) to Cr(III) of chromium hydroxide [Cr(OH)3], and Se(VI) of sodium selenate (Na₂SeO₄) to selenium Se(0), with changes of color and turbidity. XRD, SEM-EDX, and TEM-EDX analyses revealed that the chromium hydroxide [Cr(OH)₃] was formed extracellularly with nanoparticles of 20–30 nm in size, and elemental selenium Se(0) nanoparticles had a sphere shape of 50–250 nm in size. These results show that metal-reducing bacteria in groundwater can aid or accelerate precipitation of heavy metals such as Cr(VI) and Se(VI) via bioreduction processes under anoxic environments. These results may also be useful for the recovery of Cr and Se nanoparticles in natural environments.

RANCANG BANGUN APLIKASI PENDAFTARAN AKTA PPAT BERBASIS WEB DENGAN TEKNOLOGI QR CODE

Directory of Open Access Journals (Sweden)

Timothy Anggriawan

2014-10-01

Full Text Available Perkembangan ilmu pengetahuan dan teknologi telah mengalami percepatan yang tinggi. Keadaan tersebut membuat banyak hal dapat dilakukan dengan lebih mudah dan efisien. Seiring dengan hal tersebut kebutuhan akan informasi yang cepat dan akurat juga semakin tinggi. Dengan tujuan untuk menghasilkan penyajian informasi yang cepat, jelas, dan akurat sehingga dapat membantu proses pengambilan keputusan dalam proses verifikasi data. Metode dalam pembuatan aplikasi ini dibagi menjadi tiga bagian yaitu pertama, melakukan pengumpulan data Akta  PPAT. Kedua, perancangan aplikasi pencetakan Akta PPAT, QR Code, dan pengecekan Akta. Ketiga, pembuatan aplikasi pendaftaran Akta QR Code PPAT menggunakan bahasa pemrograman PHP yang dapat dijalankan pada browser. Hasil dari pembuatan aplikasi berupa aplikasi pendaftaran Akta PPAT yang dapat menampilkan proses penginputan data para pihak, pengeditan data pada Akta PPAT, pencetakan Akta QR Code. Aplikasi dapat menampilkan hasil pengecekan Akta melalui scan QR Code pada aplikasi dalam bentuk teks file, dan melakukan validasi data pada hasil scan. Simpulan yang dapat ditarik adalah aplikasi dapat menampilkan hasil cetak Akta dan QR Code.

Nitrate Enhanced Microbial Cr(VI) Reduction-Final Report

Energy Technology Data Exchange (ETDEWEB)

John F. Stolz

2011-06-15

A major challenge for the bioremediation of radionuclides (i.e., uranium, technetium) and metals (i.e., Cr(VI), Hg) is the co-occurrence of nitrate as it can inhibit metal transformation. Denitrification (nitrate reduction to dinitrogen gas) is considered the most important ecological process. For many metal and metalloid reducing bacteria, however, ammonia is the end product through respiratory nitrate reduction (RNRA). The focus of this work was to determine how RNRA impacts Cr(VI) transformation. The goal was to elucidate the specific mechanism(s) that limits Cr(VI) reduction in the presence of nitrate and to use this information to develop strategies that enhance Cr(VI) reduction (and thus detoxification). Our central hypothesis is that nitrate impacts the biotransformation of metals and metalloids in three ways 1) as a competitive alternative electron acceptor (inhibiting transformation), 2) as a co-metabolite (i.e., concomitant reduction, stimulating transformation), and 3) as an inducer of specific proteins and pathways involved in oxidation/reduction reactions (stimulating transformation). We have identified three model organisms, Geobacter metallireducens (mechanism 1), Sulfurospirillum barnesii, (mechasism 2), and Desulfovibrio desulfuricans (mechanisms 3). Our specific aims were to 1) investigate the role of Cr(VI) concentration on the kinetics of both growth and reduction of nitrate, nitrite, and Cr(VI) in these three organisms; 2) develop a profile of bacterial enzymes involved in nitrate transformation (e.g., oxidoreductases) using a proteomic approach; 3) investigate the function of periplasmic nitrite reductase (Nrf) as a chromate reductase; and 4) develop a strategy to maximize microbial chromium reduction in the presence of nitrate. We found that growth on nitrate by G. metallireducens was inhibited by Cr(VI). Over 240 proteins were identified by LC/MS-MS. Redox active proteins, outer membrane heavy metal efflux proteins, and chemotaxis sensory

Perancangan Dan Realisasi Sistem Transmisi Data GPS Menggunakan Teknologi SMS (Short Messaging Service Sebagai Aplikasi Sistem Personal Tracking

Directory of Open Access Journals (Sweden)

DECY NATALIANA

2017-06-01

Full Text Available Abstrak Berprinsip pada pengembangan teknologi dan aplikasi dari sistem penjejakan posisi (tracking, maka dibuatlah sistem personal tracking dengan mentransmisikan data GPS (Global Positioning System dengan menggunakan teknologi SMS (Short Messaging Service pada jaringan GSM (Global System for Mobile Communications sebagai media transmisinya.  Dengan sistem GPS akan diperoleh data garis lintang, serta garis bujur dari GPS receiver.  Data tersebut akan diteruskan oleh mikrokontroler untuk dikirim ke ponsel pengamat melalui komunikasi SMS.  Hasil pengujian menunjukkan bahwa device personal tracking berhasil mengirimkan data berupa IMEI, Tanggal satelit, waktu satelit, koordinat longitude, koordinat latitude, dan jumlah satelit yang berhasil ditangkap oleh device ke ponsel pengamat.  Dari data koordinat tersebut pengamat dapat memantau posisi device personal tracking berada dengan bantuan aplikasi pendukung yaitu Google Maps. Kata kunci: GPS, Personal Tracking, SMS, Google Maps.   Abstract Base on technology and application development of tracking, personal tracking system was made by transmiting GPS (Global Positioning System data using SMS (Short Messaging Service technology with GSM (Global System for Mobile Communications network as transmitter media.  BY GPS system, we can get datas such as latitude and longitude of GPS receiver.  Those datas will be processed by microcontroller to be sent from GSM/GPRS module to user cellular phone through SMS communication.  The test result showed that the device can be sending datas such as IMEI, UTC date, UTC time, longitude coordinate, latitude coordinate, and number sattelite which detected by device to user’s phonecell.  From those coordinate, user can be monitoring the device’s position with the Google Maps application. Keywords: GPS, Personal Tracking, SMS, Google Maps.

Learning the vi and Vim Editor

CERN Document Server

Robbins, Arnold; Hannah, Elbert

2008-01-01

There's nothing that hard-core Unix and Linux users are more fanatical about than their text editor. Editors are the subject of adoration and worship, or of scorn and ridicule, depending upon whether the topic of discussion is your editor or someone else's. vi has been the standard editor for close to 30 years. Popular on Unix and Linux, it has a growing following on Windows systems, too. Most experienced system administrators cite vi as their tool of choice. And since 1986, this book has been the guide for vi. However, Unix systems are not what they were 30 years ago, and neither is this

Chromium(VI) bioremediation by probiotics.

Science.gov (United States)

Younan, Soraia; Sakita, Gabriel Z; Albuquerque, Talita R; Keller, Rogéria; Bremer-Neto, Hermann

2016-09-01

Chromium is a common mineral in the earth's crust and can be released into the environment from anthropogenic sources. Intake of hexavalent chromium (Cr(VI)) through drinking water and food causes toxic effects, leading to serious diseases, and is a commonly reported environmental problem. Microorganisms can mitigate or prevent the toxic effects caused by heavy metals in addition to having effective resistance mechanisms to prevent cell damage and bind to these metals, sequestering them from the cell surface and removing them from the body. Species of Lactobacillus, Streptococcus, Bacillus and Bifidobacterium present in the human mouth and gut and in fermented foods have the ability to bind and detoxify some of these substances. This review address the primary topics related to Cr(VI) poisoning in animals and humans and the use of probiotics as a way to mitigate or prevent the toxic effects caused by Cr(VI). Further advances in the genetic knowledge of such microorganisms may lead to discoveries which will clarify the most active microorganisms that act as bioprotectants in bodies exposed to Cr(VI) and are an affordable option for people and animals intoxicated by the oral route. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

PERAMALAN PENENTUAN JUMLAH PERMINTAAN KONSUMEN BERBASIS TEKNOLOGI INFORMASI TERHADAP PRODUK BORDIR PADA KOTA TASIKMALAYA

Directory of Open Access Journals (Sweden)

Lies Sunarmintyastuti

2016-12-01

Full Text Available Peramalan penentuan jumlah permintaan konsumen berbasis teknologi informasi terhadap produk bordir di Kota Tasikmalaya, mempunyai tujuan khusus untuk menentukan jumlah kebutuhan permintaan konsumen secara periodik, berkala dan pola kebutuhan permintaan konsumen dimasa yang akan datang secara trend, musiman. Penelitian ini berawal dari konsep pemikiran bagaimana supaya produsen bordir di Kota Tasikmalaya mendapatkan pendapatan yang optimal dan efisien dalam biaya produksi bordir mereka. Pendekatan peramalan dalam penelitian ini menggunakan metode Time Series dengan menggunakan Single Exponential Smoothing Modeluntuk mendapatkan nilai peramalan secara periodik, Double Exponential Smoothing Modeluntuk mendapatkan nilai peramalan secara trend dan Triple Exponential SmoothingModeldengan Multiplicative Seasonal Modeluntuk mendapatkan nilai peramalan secara musiman, serta pengujian peramalan menggunakan MAD, MAPE dan MSE untuk mencari error terkecil. Pada tahap berikutnya dibangun sebuah sistem peramalan penentuan permintaan konsumen dengan menggunakan metode pengembangan sistem waterfall dan pembuatansoftware yang dirancang menggunakan bahasa pemrograman Java dengan editor NetBeans dan database MySQL.

Demand-side management project for Tenaga Nasional Berhad: Energy efficiency study: Institut Teknologi Mara (ITM) complex. Final report. Export trade information

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-03-01

This study, conducted by the California Energy Commission, was funded by the U.S. Trade and Development Agency. The report focuses on energy efficiency and conservation measures at the Institut Teknologi Mara (ITM) Complex for Tenaga Nasional Berhad in Malaysia. The study is divided into the following sections: Preface; (1.0) Executive Summary; (2.0) Facility Background and Site Information; (3.0) Site Energy Use; (4.0) Energy Using Systems; (5.0) On-Site Electricity and Energy Generation; (6.0) Technical Project Summary; Figures, Tables, Appendices.

Titanium dioxide-based DGT for measuring dissolved As(V), V(V), Sb(V), Mo(VI) and W(VI) in water

DEFF Research Database (Denmark)

Panther, Jared G.; Stewart, Ryan R.; Teasdale, Peter R.

2013-01-01

A titanium dioxide-based DGT method (Metsorb-DGT) was evaluated for the measurement of As(V), V(V), Sb(V), Mo(VI), W(VI) and dissolved reactive phosphorus (DRP) in synthetic waters. Mass vs. time DGT deployments at pH 6.06 (0.01 mol L-1 NaNO3) demonstrated linear uptake of all analytes (R2...... for deployment times >4 h (CDGT=0.27-0.72). For ferrihydrite-DGT, CDGT/CSol values in the range 0.92-1.16 were obtained for As(V), V(V) and DRP, however, Mo(VI), Sb(V) and W(VI) could not be measured to within 15% of the solution concentration (C DGT/CSol 0.02-0.83)....

Når vi taler om 68

DEFF Research Database (Denmark)

Jensen, Henrik; Metz, Georg

Når vi taler om 68 er en intellektuel samtale mellem to ligeværdige gentlemen og skallesmækkere. En essayistisk dyst om porno, RAF, Pittelkow og livsfilosofi......Når vi taler om 68 er en intellektuel samtale mellem to ligeværdige gentlemen og skallesmækkere. En essayistisk dyst om porno, RAF, Pittelkow og livsfilosofi...

Research progress in the electrochemical synthesis of ferrate(VI)

International Nuclear Information System (INIS)

Macova, Zuzana; Bouzek, Karel; Hives, Jan; Sharma, Virender K.; Terryn, Raymond J.; Baum, J. Clayton

2009-01-01

There is renewed interest in the +6 oxidation state of iron, ferrate (VI) (Fe VI O 4 2- ), because of its potential as a benign oxidant for organic synthesis, as a chemical in developing cleaner ('greener') technology for remediation processes, and as an alternative for environment-friendly battery cathodes. This interest has led many researchers to focus their attention on the synthesis of ferrate(VI). Of the three synthesis methods, electrochemical, wet chemical and thermal, electrochemical synthesis has received the most attention due to its ease and the high purity of the product. Moreover, electrochemical processes use an electron as a so-called clean chemical, thus avoiding the use of any harmful chemicals to oxidize iron to the +6 oxidation state. This paper reviews the development of electrochemical methods to synthesize ferrate(VI). The approaches chosen by different laboratories to overcome some of the difficulties associated with the electrochemical synthesis of ferrate(VI) are summarized. Special attention is paid to parameters such as temperature, anolyte, and anode material composition. Spectroscopic work to understand the mechanism of ferrate(VI) synthesis is included. Recent advances in two new approaches, the use of an inert electrode and molten hydroxide salts, in the synthesis of ferrate(VI) are also reviewed. Progress made in the commercialization of ferrate(VI) continuous production is briefly discussed as well

Synthesis, characterization and oxidative behaviour of dioxoruthenium(VI) complexes

International Nuclear Information System (INIS)

Agarwal, D.D.; Rastogi, Rachana

1995-01-01

Dioxoruthenium(VI) complexes are found to give low yield of epoxide but good yield of cyclohexanone. The complexes are electro active giving metal centered Ru VI /Ru V couple. Cis-stilbene gives trans epoxide and benzaldehyde. Norbornene gives exo epoxy norbornene. The selectivity for allylic oxidation is high. In the present note the synthesis of dioxoruthenium(VI) complexes and their oxidation behaviour is reported. The dioxoruthenium(VI) complexes have been stoichiometrically found to be good oxidants. (author). 21 refs., 1 tab

Inhibition of bacterial U(VI) reduction by calcium

International Nuclear Information System (INIS)

Brooks, Scott C.; Fredrickson, Jim K.; Carroll, S. L.; Kennedy, David W.; Zachara, John M.; Plymale, Andrew E.; Kelly, S. D.; Kemner, K. M.; Fendorf, S.

2003-01-01

The rapid kinetics of bacterial U(VI) reduction and low solubility of uraninite (UO2,cr) make this process an attractive option for removing uranium from groundwater. Nevertheless, conditions that may promote or inhibit U(VI) reduction are not well-defined. Recent descriptions of Ca-UO2-CO3 complexes indicate that these species may dominate the aqueous speciation of U(VI) in many environments. We monitored the bacterial reduction of U(VI) in bicarbonate-buffered solution in the presence and absence of Ca. XAFS measurements confirmed the presence of a Ca-U(VI)-CO3 complex in the initial solutions containing calcium. Calcium, at millimolar concentrations (0.45-5 mM), caused a significant decrease in the rate and extent of bacterial U(VI) reduction. Both facultative (Shewanella putrefaciens strain CN32) and obligate (Desulfovibrio desulfuricans, Geobacter sulfurreducens) anaerobic bacteria were affected by the presence of calcium. Reduction of U(VI) ceased when the calculated system Eh re ached -0.046+/- 0.001 V, based on the Ca2UO2(CO3)(3) -- > UO2,cr couple. The results are consistent with the hypothesis that U is a less energetically favorable electron acceptor when the Ca-UO2-CO3 complexes are present. The results do not support Ca inhibition caused by direct interactions with the cells or with the electron donor as the reduction of fumarate or Tc(VII)O-4(-) under identical conditions was unaffected by the presence of Ca

New generation ion-imprinted nanocarrier for removal of Cr(VI) from wastewater

International Nuclear Information System (INIS)

Uygun, Murat; Feyzioğlu, Esra; Özçalışkan, Emir; Caka, Müşerref; Ergen, Aygen; Akgöl, Sinan; Denizli, Adil

2013-01-01

The purpose of this study was to prepare a novel ion-imprinted nanoparticle to remove Cr(VI) ions from waste water. For this, Cr(VI) ions were complexed with 2-methacryloylamido histidine (MAH) and then Cr(VI)-imprinted poly(HEMAH) nanoparticles were synthesized by surfactant-free emulsion polymerization technique. The templates, Cr(VI) ions, were removed from the nanoparticles using 0.1 M of HNO 3 solution. The specific surface area of the Cr(VI)-imprinted poly(HEMAH) nanoparticles was found to be 1,397.85 m 2 /g, and the particle size was calculated as 155.3 nm. These Cr(VI)-imprinted nanoparticles were used for the adsorption/desorption of Cr(VI) ions from its aqueous solutions. The effects of initial Cr(VI) concentration and medium pH on the Cr(VI) adsorption capacity were also studied. The maximum adsorbed amount of Cr(VI) on the imprinted nanoparticles was found to be 3,830.58 mg/g nanoparticle in pH 4.0. In order to investigate the selectivity of the imprinted nanoparticle, adsorption studies were repeated using Cr(III) ions. The selectivity results demonstrated that Cr(VI)-imprinted poly(HEMAH) nanoparticles showed high affinity for the Cr(VI) ions than Cr(III). The Cr(VI)-imprinted nanoparticles were used several times without decreasing their Cr(VI) adsorption capacities

New generation ion-imprinted nanocarrier for removal of Cr(VI) from wastewater

Science.gov (United States)

Uygun, Murat; Feyzioğlu, Esra; Özçalışkan, Emir; Caka, Müşerref; Ergen, Aygen; Akgöl, Sinan; Denizli, Adil

2013-08-01

The purpose of this study was to prepare a novel ion-imprinted nanoparticle to remove Cr(VI) ions from waste water. For this, Cr(VI) ions were complexed with 2-methacryloylamido histidine (MAH) and then Cr(VI)-imprinted poly(HEMAH) nanoparticles were synthesized by surfactant-free emulsion polymerization technique. The templates, Cr(VI) ions, were removed from the nanoparticles using 0.1 M of HNO3 solution. The specific surface area of the Cr(VI)-imprinted poly(HEMAH) nanoparticles was found to be 1,397.85 m2/g, and the particle size was calculated as 155.3 nm. These Cr(VI)-imprinted nanoparticles were used for the adsorption/desorption of Cr(VI) ions from its aqueous solutions. The effects of initial Cr(VI) concentration and medium pH on the Cr(VI) adsorption capacity were also studied. The maximum adsorbed amount of Cr(VI) on the imprinted nanoparticles was found to be 3,830.58 mg/g nanoparticle in pH 4.0. In order to investigate the selectivity of the imprinted nanoparticle, adsorption studies were repeated using Cr(III) ions. The selectivity results demonstrated that Cr(VI)-imprinted poly(HEMAH) nanoparticles showed high affinity for the Cr(VI) ions than Cr(III). The Cr(VI)-imprinted nanoparticles were used several times without decreasing their Cr(VI) adsorption capacities.

New generation ion-imprinted nanocarrier for removal of Cr(VI) from wastewater

Energy Technology Data Exchange (ETDEWEB)

Uygun, Murat, E-mail: muygun@adu.edu.tr [Adnan Menderes University, Kocarl Latin-Small-Letter-Dotless-I Vocational and Training School (Turkey); Feyzioglu, Esra; Oezcal Latin-Small-Letter-Dotless-I skan, Emir; Caka, Mueserref; Ergen, Aygen; Akgoel, Sinan [Ege University, Department of Biochemistry, Faculty of Science (Turkey); Denizli, Adil [Hacettepe University, Department of Chemistry, Faculty of Science (Turkey)

2013-08-15

The purpose of this study was to prepare a novel ion-imprinted nanoparticle to remove Cr(VI) ions from waste water. For this, Cr(VI) ions were complexed with 2-methacryloylamido histidine (MAH) and then Cr(VI)-imprinted poly(HEMAH) nanoparticles were synthesized by surfactant-free emulsion polymerization technique. The templates, Cr(VI) ions, were removed from the nanoparticles using 0.1 M of HNO{sub 3} solution. The specific surface area of the Cr(VI)-imprinted poly(HEMAH) nanoparticles was found to be 1,397.85 m{sup 2}/g, and the particle size was calculated as 155.3 nm. These Cr(VI)-imprinted nanoparticles were used for the adsorption/desorption of Cr(VI) ions from its aqueous solutions. The effects of initial Cr(VI) concentration and medium pH on the Cr(VI) adsorption capacity were also studied. The maximum adsorbed amount of Cr(VI) on the imprinted nanoparticles was found to be 3,830.58 mg/g nanoparticle in pH 4.0. In order to investigate the selectivity of the imprinted nanoparticle, adsorption studies were repeated using Cr(III) ions. The selectivity results demonstrated that Cr(VI)-imprinted poly(HEMAH) nanoparticles showed high affinity for the Cr(VI) ions than Cr(III). The Cr(VI)-imprinted nanoparticles were used several times without decreasing their Cr(VI) adsorption capacities.

ALTERATION OF U(VI)-PHASES UNDER OXIDIZING CONDITIONS

Energy Technology Data Exchange (ETDEWEB)

A.P. Deditius; S. Utsunomiya; R.C. Ewing

2006-02-21

Uranium-(VI) phases are the primary alteration products of the UO{sub 2} in spent nuclear fuel and the UO{sub 2+x}, in natural uranium deposits. The U(VI)-phases generally form sheet structures of edge-sharing UO{sub 2}{sup 2+} polyhedra. The complexity of these structures offers numerous possibilities for coupled-substitutions of trace metals and radionuclides. The incorporation of radionuclides into U(VI)-structures provides a potential barrier to their release and transport in a geologic repository that experiences oxidizing conditions. In this study, we have used natural samples of UO{sub 2+x}, to study the U(VI)-phases that form during alteration and to determine the fate of the associated trace elements.

ALTERATION OF U(VI)-PHASES UNDER OXIDIZING CONDITIONS

International Nuclear Information System (INIS)

A.P. Deditius; S. Utsunomiya; R.C. Ewing

2006-01-01

Uranium-(VI) phases are the primary alteration products of the UO 2 in spent nuclear fuel and the UO 2+x , in natural uranium deposits. The U(VI)-phases generally form sheet structures of edge-sharing UO 2 2+ polyhedra. The complexity of these structures offers numerous possibilities for coupled-substitutions of trace metals and radionuclides. The incorporation of radionuclides into U(VI)-structures provides a potential barrier to their release and transport in a geologic repository that experiences oxidizing conditions. In this study, we have used natural samples of UO 2+x , to study the U(VI)-phases that form during alteration and to determine the fate of the associated trace elements

Oxidation of trimethoprim by ferrate(VI): kinetics, products, and antibacterial activity.

Science.gov (United States)

Anquandah, George A K; Sharma, Virender K; Knight, D Andrew; Batchu, Sudha Rani; Gardinali, Piero R

2011-12-15

Kinetics, stoichiometry, and products of the oxidation of trimethoprim (TMP), one of the most commonly detected antibacterial agents in surface waters and municipal wastewaters, by ferrate(VI) (Fe(VI)) were determined. The pH dependent second-order rate constants of the reactions of Fe(VI) with TMP were examined using acid-base properties of Fe(VI) and TMP. The kinetics of reactions of diaminopyrimidine (DAP) and trimethoxytoluene (TMT) with Fe(VI) were also determined to understand the reactivity of Fe(VI) with TMP. Oxidation products of the reactions of Fe(VI) with TMP and DAP were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Reaction pathways of oxidation of TMP by Fe(VI) are proposed to demonstrate the cleavage of the TMP molecule to ultimately result in 3,4,5,-trimethoxybenzaldehyde and 2,4-dinitropyrimidine as among the final identified products. The oxidized products mixture exhibited no antibacterial activity against E. coli after complete consumption of TMP. Removal of TMP in the secondary effluent by Fe(VI) was achieved.

Social Set Visualizer (SoSeVi) II

DEFF Research Database (Denmark)

Flesch, Benjamin; Vatrapu, Ravi

2016-01-01

This paper reports the second iteration of the Social Set Visualizer (SoSeVi), a set theoretical visual analytics dashboard of big social data. In order to further demonstrate its usefulness in large-scale visual analytics tasks of individual and collective behavior of actors in social networks......, the current iteration of the Social Set Visualizer (SoSeVi) in version II builds on recent advancements in visualizing set intersections. The development of the SoSeVi dashboard involved cutting-edge open source visual analytics libraries (D3.js) and creation of new visualizations such as of actor mobility...

Development of Delta Wing Aerodynamics Research in Universiti Teknologi Malaysia Low Speed Wind Tunnel

Directory of Open Access Journals (Sweden)

Shabudin Mat

2014-07-01

Full Text Available This paper presents wind tunnel experiment on two delta wing configurations which are differentiated by their leading edge profiles: sharp and round-edged wings. The experiments were performed as a part of the delta wing aerodynamics research development in Universiti Teknologi Malaysia, low speed tunnel (UTM-LST. Steady load balance and flow visualization tests were conducted at Reynolds numbers of 0.5, 1, and 1.5 × 106, respectively. The flow measurement at low Reynolds number was also performed at as low as speed of 5 m/s. During the experiments, laser with smoke flow visualizations test was performed on both wings. The study has identified interesting features of the interrelationship between the conventional leading edge primary vortex and the occurrence and development of the vortex breakdown above the delta wings. The results conclude the vortex characteristics are largely dependent on the Reynolds number, angle of attack, and leading-edge radii of the wing.

Fremtidens lavenergibyggeri - kan vi gøre som vi plejer?

DEFF Research Database (Denmark)

Larsen, Tine Steen

2011-01-01

Stramninger af kravene til energiforbruget i vores boliger medfører stor fokus på energiberegningen, men erfaringer fra lavenergiboliger opført i dag viser, at vi, for at sikre succes for fremtidens boliger, også skal inddrage dokumentation af indeklimaet og forbedre samarbejdet mellem arkitekter...

Chromium(VI) generation in vadose zone soils and alluvial sediments of the southwestern Sacramento Valley, California: A potential source of geogenic Cr(VI) to groundwater

International Nuclear Information System (INIS)

Mills, Christopher T.; Morrison, Jean M.; Goldhaber, Martin B.; Ellefsen, Karl J.

2011-01-01

Highlights: → Southern Sacramento Valley soil and sediment has abundant naturally-occurring Cr(III). → Cr(III) resides mainly in chromite but some is associated with clays and Fe oxides. → Cr(VI) is mostly absent in surface soil but ubiquitous in deeper soil and sediment. → Cr(VI) increased linearly with time during lab soil incubations with no additions. → Cation exchange processes resulted in greater Cr(VI) generation rates. - Abstract: Concentrations of geogenic Cr(VI) in groundwater that exceed the World Health Organization's maximum contaminant level for drinking water (50 μg L -1 ) occur in several locations globally. The major mechanism for mobilization of this Cr(VI) at these sites is the weathering of Cr(III) from ultramafic rocks and its subsequent oxidation on Mn oxides. This process may be occurring in the southern Sacramento Valley of California where Cr(VI) concentrations in groundwater can approach or exceed 50 μg L -1 . To characterize Cr geochemistry in the area, samples from several soil auger cores (approximately 4 m deep) and drill cores (approximately 25 m deep) were analyzed for total concentrations of 44 major, minor and trace elements, Cr associated with labile Mn and Fe oxides, and Cr(VI). Total concentrations of Cr in these samples ranged from 140 to 2220 mg per kg soil. Between 9 and 70 mg per kg soil was released by selective extractions that target Fe oxides, but essentially no Cr was associated with the abundant reactive Mn oxides (up to ∼1000 mg hydroxylamine-reducible Mn per kg soil was present). Both borehole magnetic susceptibility surveys performed at some of the drill core sites and relative differences between Cr released in a 4-acid digestion versus total Cr (lithium metaborate fusion digestion) suggest that the majority of total Cr in the samples is present in refractory chromite minerals transported from ultramafic exposures in the Coast Range Mountains. Chromium(VI) in the samples studied ranged from 0 to 42 �

Chromium(VI) generation in vadose zone soils and alluvial sediments of the southwestern Sacramento Valley, California: A potential source of geogenic Cr(VI) to groundwater

Energy Technology Data Exchange (ETDEWEB)

Mills, Christopher T., E-mail: cmills@usgs.gov [United States Geological Survey, Crustal Geophysics and Geochemistry Science Center, Denver Federal Center, MS 964D, Denver, CO 80225 (United States); Morrison, Jean M.; Goldhaber, Martin B.; Ellefsen, Karl J. [United States Geological Survey, Crustal Geophysics and Geochemistry Science Center, Denver Federal Center, MS 964D, Denver, CO 80225 (United States)

2011-08-15

Highlights: > Southern Sacramento Valley soil and sediment has abundant naturally-occurring Cr(III). > Cr(III) resides mainly in chromite but some is associated with clays and Fe oxides. > Cr(VI) is mostly absent in surface soil but ubiquitous in deeper soil and sediment. > Cr(VI) increased linearly with time during lab soil incubations with no additions. > Cation exchange processes resulted in greater Cr(VI) generation rates. - Abstract: Concentrations of geogenic Cr(VI) in groundwater that exceed the World Health Organization's maximum contaminant level for drinking water (50 {mu}g L{sup -1}) occur in several locations globally. The major mechanism for mobilization of this Cr(VI) at these sites is the weathering of Cr(III) from ultramafic rocks and its subsequent oxidation on Mn oxides. This process may be occurring in the southern Sacramento Valley of California where Cr(VI) concentrations in groundwater can approach or exceed 50 {mu}g L{sup -1}. To characterize Cr geochemistry in the area, samples from several soil auger cores (approximately 4 m deep) and drill cores (approximately 25 m deep) were analyzed for total concentrations of 44 major, minor and trace elements, Cr associated with labile Mn and Fe oxides, and Cr(VI). Total concentrations of Cr in these samples ranged from 140 to 2220 mg per kg soil. Between 9 and 70 mg per kg soil was released by selective extractions that target Fe oxides, but essentially no Cr was associated with the abundant reactive Mn oxides (up to {approx}1000 mg hydroxylamine-reducible Mn per kg soil was present). Both borehole magnetic susceptibility surveys performed at some of the drill core sites and relative differences between Cr released in a 4-acid digestion versus total Cr (lithium metaborate fusion digestion) suggest that the majority of total Cr in the samples is present in refractory chromite minerals transported from ultramafic exposures in the Coast Range Mountains. Chromium(VI) in the samples studied ranged

EVALUASI KINERJA TEKNOLOGI INFORMASI DANA PENSIUN SEKOLAH KRISTEN SALATIGA MENGGUNAKAN FRAMEWORK COBIT 5

Directory of Open Access Journals (Sweden)

Yosafanto Adi

2017-04-01

Full Text Available Sistem Keuangan merupakan infrastruktur teknologi informasi yang ada di Dana Pensiun Sekolah Kristen Salatiga. Sistem Keuangan dapat mengelola berbagai laporan mulai dari pencatatan kas hingga pembuatan laporan keuangan. Pentingnya sistem keuangan dalam operasional, menjadikannya  harus dalam kondisi yang optimal. Perlu adanya kontrol dan evaluasi terhadap kinerja sistem informasi (SI agar sistem yang dibangun organisasi dapat mencapai tujuan bisnis. Untuk itu diperlukannya evaluasi kinerja sistem keuangan, pada penelitian ini standar yang digunakan untuk proses evaluasi kinerja yaitu COBIT 5. Framework COBIT 5 dapat menjadi sebuah alat evaluasi kinerja SI untuk menilai seberapa jauh SI  dapat memenuhi kebutuhan tujuan bisnis. Berdasarkan evaluasi kinerja pada sistem keuangan menggunakan COBIT 5 didapatkan hasil bahwa organisasi sudah mengimplementasikan semua proses, yang berarti Dana Pensiun Sekolah Kristen Salatiga sudah mencapai tingkat kapabilitas pada level 1 (Performed Process maupun level 2 (Managed Process. Untuk memperbaiki tingkat kapabilitas proses-proses TI tersebut, maka COBIT 5 telah memberikan panduan berupa rekomendasi guna penyelerasan antara tujuan bisnis Dana Pensiun Sekolah Kristen dengan tujuan TI dalam rangka meningkatkan efisiensi dan efektifitas Sistem Keuangan untuk mencapai tujuan organisasi.

Modelling biological Cr(VI) reduction in aquifer microcosm column systems.

Science.gov (United States)

Molokwane, Pulane E; Chirwa, Evans M N

2013-01-01

Several chrome processing facilities in South Africa release hexavalent chromium (Cr(VI)) into groundwater resources. Pump-and-treat remediation processes have been implemented at some of the sites but have not been successful in reducing contamination levels. The current study is aimed at developing an environmentally friendly, cost-effective and self-sustained biological method to curb the spread of chromium at the contaminated sites. An indigenous Cr(VI)-reducing mixed culture of bacteria was demonstrated to reduce high levels of Cr(VI) in laboratory samples. The effect of Cr(VI) on the removal rate was evaluated at concentrations up to 400 mg/L. Following the detailed evaluation of fundamental processes for biological Cr(VI) reduction, a predictive model for Cr(VI) breakthrough through aquifer microcosm reactors was developed. The reaction rate in batch followed non-competitive rate kinetics with a Cr(VI) inhibition threshold concentration of approximately 99 mg/L. This study evaluates the application of the kinetic parameters determined in the batch reactors to the continuous flow process. The model developed from advection-reaction rate kinetics in a porous media fitted best the effluent Cr(VI) concentration. The model was also used to elucidate the logistic nature of biomass growth in the reactor systems.

Diverse functions of myosin VI elucidated by an isoform-specific α-helix domain.

Science.gov (United States)

Wollscheid, Hans-Peter; Biancospino, Matteo; He, Fahu; Magistrati, Elisa; Molteni, Erika; Lupia, Michela; Soffientini, Paolo; Rottner, Klemens; Cavallaro, Ugo; Pozzoli, Uberto; Mapelli, Marina; Walters, Kylie J; Polo, Simona

2016-04-01

Myosin VI functions in endocytosis and cell motility. Alternative splicing of myosin VI mRNA generates two distinct isoform types, myosin VI(short) and myosin VI(long), which differ in the C-terminal region. Their physiological and pathological roles remain unknown. Here we identified an isoform-specific regulatory helix, named the α2-linker, that defines specific conformations and hence determines the target selectivity of human myosin VI. The presence of the α2-linker structurally defines a new clathrin-binding domain that is unique to myosin VI(long) and masks the known RRL interaction motif. This finding is relevant to ovarian cancer, in which alternative myosin VI splicing is aberrantly regulated, and exon skipping dictates cell addiction to myosin VI(short) in tumor-cell migration. The RRL interactor optineurin contributes to this process by selectively binding myosin VI(short). Thus, the α2-linker acts like a molecular switch that assigns myosin VI to distinct endocytic (myosin VI(long)) or migratory (myosin VI(short)) functional roles.

Pola Proses Penyebaran dan Penerimaan Informasi Teknologi Kamera DSLR

Directory of Open Access Journals (Sweden)

Sidiq Setyawan

2017-10-01

Full Text Available Abstrak   Kamera DSLR sebagai sebuah produk inovasi memiliki cara tersendiri untuk dapat diterima dan diadopsi oleh sebuah sistem sosial khususnya fotografer non profesional di Kota Solo. Difusi inovasi menjelaskan secara sistematis bagaimana sebuah produk inovasi DSLR disebarluaskan dan diterima oleh golongan inovasi di dalamnya. Sebagai sebuah bentuk komunikasi khusus, dalam teori difusi inovasi terdapat dua pokok utama kajian komunikasi, yakni bagaimana seorang komunikator maupun komunikan dalam golongan inovasi bertindak untuk menyebarkan pesan dan menerima pesan. Kedua pokok bahasan ini yang menjadi kunci bagaimana sebuah produk inovasi mampu efektif disebarkan dan diterima (diadopsi oleh golongan inovasi di dalamnya. Jenis penelitian ini adalah penelitian deskiptif kualitatif. Peneliti menggunakan metode studi kasus. Studi kasus cocok digunakan bila penelitian berkenaan dengan how dan why. Peneliti menjabarkan hasil dari penelitian yang dilakukan dalam bentuk narasi. Sampel dari populasi yang diambil melalui proses teknik cuplikan dengan maximum variation sampling atau pengambilan sampel variasi maksimum. Selain menggunakan teknik sampel variasi maksimum, peneliti menggunakan teknik cuplikan snowball sampling. Peneliti mengambil sampel fotografer non profesional di Kota Solo. Teknik pengumpulan data melalui in-depth interview (wawancara mendalam dan observasi lingkungan terhadap sampel penelitian. Untuk validasi data, peneliti menggunakan triangulasi sumber Hasil penelitian ini menunjukan bahwa memiliki memiliki karakteristik dan saluran komunikasi komunikasi tersendiri ketika mereka menerima informasi mengenai inovasi dan memutuskan untuk mengadopsi teknologi tersebut. Hal ini misalnya bisa dilihat dari pemilihan media dalam berkomunikasi dan menggunakan berbagai media untuk referensi mengumpulkan informasi terkait dengan inovasi.   Kata kunci: difusi inovasi, innovator, early adopter, early majority, late majority, pola komunikasi.

The reduction of Np(VI) and Pu(VI) by organic chelating agents

International Nuclear Information System (INIS)

Reed, D.T.; Aase, S.B.; Banaszak, J.E.

1998-01-01

The reduction of NpO 2+ and PuO 2 2+ by oxalate. citrate, and ethylenediaminetetraacetic acid (EDTA) was investigated in low ionic strength media and brines. This was done to help establish the stability of the An(VI) oxidation state in the presence of organic complexants. The stability of the An(VI) oxidation state depended on the pH and relative strength of the various oxidation state-specific complexes. At low ionic strength and pH 6, NpO 2 O 2+ was rapidly reduced to form NpO 2 + organic complexes. At longer times, Np(IV) organic complexes were observed in the presence of citrate. PuO 2 2+ was predominantly reduced to Pu 4+ , resulting in the formation of organic complexes or polymeric/hydrolytic precipitates. The relative rates of reduction to the An(V) complex were EDTA > citrate > oxalate. Subsequent reduction to An(IV) complexes, however, occurred in the following order: citrate > EDTA > oxalate because of the stability of the An(V)-EDTA complex. The presence of organic complexants led to the rapid reduction of NpO 2 2+ and PuO 2 P 2+ in G-seep brine at pHs 5 and 7. At pHs 8 and 10 in ERDA-6 brine, carbonate and hydrolytic complexes predominated and slowed down or prevented the reduction of An(VI) by the organics present

Contribution to the study of the redox couple Np(VI)/Np(V) in the presence of uranium(VI) in solutions of nitric acid and nitrous acid; Contribution a l'etude du comportement redox du couple Np(VI)/Np(V) en presence d'uranium VI dans les solutions constituees d'acide nitrique et d'acide nitreux

Energy Technology Data Exchange (ETDEWEB)

Arpigny, S. [CEA Marcoule, Dept. de Radiochimie et Procedes, DRP, 30 (France)

2001-07-01

The redox behavior of the Np(VI)/Np(V) couple was the subject of a spectrometric study of the Np(VI) reduction reaction in nitric acid solutions (4 to 5 M) containing variable concentrations (1.5 to 3.5 x 10{sup -3} M) of nitrous acid. A low nitrous acid concentration and a high nitric acid concentration were found to favor the stabilization of Np(VI). The stoichiometric coefficients of nitrous acid and nitric acid in the Np(VI) reduction reaction were determined thermodynamically, although only the reaction order with respect to HNO{sub 2} could be calculated from a kinetic analysis. Adding nitrate ions to a HNO{sub 3}/HNO{sub 2} solution enhanced the stability of neptunium at oxidation state +VI, but also increased the reduction rate. When uranium(VI) was added to the HNO{sub 3}/HNO{sub 2} solutions, the total quantity of neptunium at oxidation state +V (either free or as a Np(V)-U(VI) complex) remained practically unchanged, as did the Np(VI) reduction rate. The electrochemical behavior of the Np(VI)/Np(V) couple was investigated in a weak acidic medium by voltammetry with an ultra-micro-electrode (UME). The oxidation wave limiting current variation was a linear function of the Np(V) concentration when a gold UME was used, but not with a platinum UME; the reduction wave limiting current variation versus the Np(V) concentration was linear with either gold or platinum UMEs. The presence of the Np(V)-U(VI) complex in the neptunium solutions was characterized by a shift in the normal apparent potential of the Np(VI)/Np(V) couple toward anodic potentials consistent with the previously determined values of the complexation constants. (author)

Chromium(VI) generation in vadose zone soils and alluvial sediments of the southwestern Sacramento Valley, California: a potential source of geogenic Cr(VI) to groundwater

Science.gov (United States)

Mills, Christopher T.; Morrison, Jean M.; Goldhaber, Martin B.; Ellefsen, Karl J.

2011-01-01

Concentrations of geogenic Cr(VI) in groundwater that exceed the World Health Organization’s maximum contaminant level for drinking water (50 μg L−1) occur in several locations globally. The major mechanism for mobilization of this Cr(VI) at these sites is the weathering of Cr(III) from ultramafic rocks and its subsequent oxidation on Mn oxides. This process may be occurring in the southern Sacramento Valley of California where Cr(VI) concentrations in groundwater can approach or exceed 50 μg L−1. To characterize Cr geochemistry in the area, samples from several soil auger cores (approximately 4 m deep) and drill cores (approximately 25 m deep) were analyzed for total concentrations of 44 major, minor and trace elements, Cr associated with labile Mn and Fe oxides, and Cr(VI). Total concentrations of Cr in these samples ranged from 140 to 2220 mg per kg soil. Between 9 and 70 mg per kg soil was released by selective extractions that target Fe oxides, but essentially no Cr was associated with the abundant reactive Mn oxides (up to ~1000 mg hydroxylamine-reducible Mn per kg soil was present). Both borehole magnetic susceptibility surveys performed at some of the drill core sites and relative differences between Cr released in a 4-acid digestion versus total Cr (lithium metaborate fusion digestion) suggest that the majority of total Cr in the samples is present in refractory chromite minerals transported from ultramafic exposures in the Coast Range Mountains. Chromium(VI) in the samples studied ranged from 0 to 42 μg kg−1, representing a minute fraction of total Cr. Chromium(VI) content was typically below detection in surface soils (top 10 cm) where soil organic matter was high, and increased with increasing depth in the soil auger cores as organic matter decreased. Maximum concentrations of Cr(VI) were up to 3 times greater in the deeper drill core samples than the shallow auger cores. Although Cr(VI) in these vadose zone soils and sediments was only a

Vi behøver innovation

DEFF Research Database (Denmark)

McAloone, Tim C.

2007-01-01

-Produktion og Maskiner. Innovation og bæredygtighed er to områder som vi i Skandinavien giver meget stor opmærksomhed for at kunne vedligeholde vores globale konkurrencekraft og stærke velfærdssamfund. Gennem årene har mange brancher bidraget til skabelsen af vidensbaserede innovationer, og det faktum, at de......Analyse: Vi behøver innovation En ny miljøbølge ruller, og danske virksomheder bør ride med Af Tim McAloone, fredag 02. feb 2007 kl. 04:50 Tim McAloone Lektor og ph.d. ved Institut for mekanik, energi og konstruktion ved DTU. Tim McAloone skriver fremover jævnligt kommentarer i Ingeniøren...... skandinaviske lande er relativt små, har ledt til en interessant evne til at etablere og derefter samarbejde inden for tætte netværk, som strækker sig over både faglige og geografiske grænser. Samtidig har vi set miljøhensyn vinde og tabe samfundsmæssig og industriel opmærksomhed på en nærmest periodisk basis...

Thermodynamic analysis of Cr(VI) extraction using TOPO impregnated membranes

Energy Technology Data Exchange (ETDEWEB)

Praveen, Prashant; Loh, Kai-Chee, E-mail: chelohkc@nus.edu.sg

2016-08-15

Highlights: • Cr(VI) extraction by extractant impregnated membranes (EIM) was investigated. • EIM exhibited high extraction efficiency, mass transfer rate and stability. • Mass transfer mechanism was proposed based on kinetics and equilibrium data. • Uptake of Cr(VI) by EIMs was endothermic and spontaneous. • Cr(VI) extraction by EIMs was dominated by physical interactions. - Abstract: Solid/liquid extraction of Cr(VI) was accomplished using trioctylphosphine oxide impregnated polypropylene hollow fiber membranes. Extraction of 100–500 mg/L Cr(VI) by the extractant impregnated membranes (EIM) was characterized by high uptake rate and capacity, and equilibrium was attained within 45 min of contact. Extraction equilibrium was pH-dependent (at an optimal pH 2), whereas stripping using 0.2 M sodium hydroxide yielded the highest recovery of 98% within 60 min. The distribution coefficient was independent of initial Cr(VI) concentration, and the linear distribution equilibrium isotherm could be modeled using Freundlich isotherm. The mass transfer kinetics of Cr(VI) was examined using pseudo-second-order and intraparticle diffusion models and a mass transfer mechanism was deduced. The distribution coefficient increased with temperature, which indicated endothermic nature of the reaction. Enthalpy and entropy change during Cr(VI) extraction were positive and varied in the range of 37–49 kJ/mol and 114–155 J/mol, respectively. The free energy change was negative, confirming the feasibility and spontaneity of the mass transfer process. Results obtained suggest that EIMs are efficient and sustainable for extraction of Cr(VI) from wastewater.

Influence of Calcium on Microbial Reduction of Solid Phase Uranium (VI)

International Nuclear Information System (INIS)

Liu, Chongxuan; Jeon, Byong-Hun; Zachara, John M.; Wang, Zheming

2007-01-01

The effect of calcium on microbial reduction of a solid phase U(VI), sodium boltwoodite (NaUO2SiO3OH · 1.5H2O), was evaluated in a culture of a dissimilatory metal-reducing bacterium (DMRB), Shewanella oneidensis strain MR-1. Batch experiments were performed in a non-growth bicarbonate medium with lactate as electron donor at pH 7 buffered with PIPES. Calcium increased both the rate and extent of Na-boltwoodite dissolution by increasing its solubility through the formation of a ternary aqueous calcium-uranyl-carbonate species. The ternary species, however, decreased the rates of microbial reduction of aqueous U(VI). Laser-induced fluorescence spectroscopy (LIFS) and transmission electron microscopy (TEM) revealed that microbial reduction of solid phase U(VI) is a sequentially coupled process of Na-boltwoodite dissolution, U(VI) aqueous speciation, and microbial reduction of dissolved U(VI) to U(IV) that accumulated on bacterial surfaces/periplasm. The overall rates of microbial reduction of solid phase U(VI) can be described by the coupled rates of dissolution and microbial reduction that were both influenced by calcium. The results demonstrated that dissolved U(VI) concentration during microbial reduction was a complex function of solid phase U(VI) dissolution kinetics, aqueous U(VI) speciation, and microbial activity

A simple Cr(VI)–S(IV)–O{sub 2} system for rapid and simultaneous reduction of Cr(VI) and oxidative degradation of organic pollutants

Energy Technology Data Exchange (ETDEWEB)

Yuan, Yanan; Yang, Shaojie [Department of Environmental Science, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, 430079 (China); Zhou, Danna, E-mail: zdncug@163.com [Faculty of Material Science and Chemistry, China University of Geosciences, Wuhan 430074 (China); Wu, Feng [Department of Environmental Science, Hubei Key Lab of Biomass Resource Chemistry and Environmental Biotechnology, School of Resources and Environmental Science, Wuhan University, 430079 (China)

2016-04-15

Highlights: • Rapid and simultaneous reduction of Cr(VI) and degradation of organic pollutants occur. • Oxysulfur radicals generated in Cr(VI)–S(IV)–O{sub 2} system oxidize the organic pollutants. • Acidic pH facilitates the reactions from both directions of reduction and oxidation. • Degradation potential of aromatic amines depends on the substituted groups. • Cr(VI)–S(IV)–O{sub 2} system is promising for “waste control by waste”. - Abstract: Hexavalent chromium (Cr(VI)), a heavy-metal contaminant, can be easily reduced to less toxic trivalent chromium (Cr(III)) by sulfite ions (S(IV)). However, S(IV) has not drawn as much attention as the ferrous ion has. We report herein a novel Cr(VI)–S(IV)–O{sub 2} system containing sulfite ions that rapidly and simultaneously reduces Cr(VI) and oxidize organic pollutants in the presence of oxygen in aqueous solutions. This Cr(VI)–S(IV)-O{sub 2} system contains the initiator Cr(VI), the reductant S(IV), and the oxidant O{sub 2}, which produce oxysulfur radicals (mainly SO{sub 4}·{sup −} and SO{sub 5}·{sup −}) and hydroxyl radicals (OH·). The Cr(VI)/S(IV) molar ratio, pH, and oxygen content play important roles in the entire reaction system. Acidic conditions (pH 3.0) facilitated degradation of organic compounds and reduction of Cr(VI) as well. In addition, experiments of rapid degradation of several kinds of organic pollutants such as azo dye (acid orange 7, AO7), aniline, phenol, bisphenol A etc were also conducted. Preliminary results show that the removal rates of the analogs of phenols or aromatic amines in this Cr(VI)–S(IV)–O{sub 2} system have a relationship with the electronic parameters (Hammett constant, σ) of the substituted groups. Thus, the Cr(VI)–S(IV)–O{sub 2} system, provides an excellent strategy of “waste control by waste” for removing multiple industrial contaminants.

Service quality that improves customer satisfaction in a university: a case study in Institut Teknologi Indonesia

Science.gov (United States)

Theresia, L.; Bangun, R.

2017-12-01

Universities should provide better service quality to get more customers. The purpose of this study was to find service quality which has impact on the increasing of customer satisfaction in a university. This study is a case study in Institut Teknologi Indonesia (ITI). The result of the study will help ITI to improve its service quality to increase customer satisfaction. This study employs path analysis technique. The data were collected through questionnaires developed from the literature. Questionnaires have two parts namely 1) service quality and 2) customer satisfaction. Service quality is measured through 22 questions with five service quality dimensions: 1) Tangibles, 2) Reliability, 3) Responsiveness, 4) Assurance and 5) Empathy. Customer Satisfaction is measured through 4 questions. The data then are processed by SPSS. The results showed that the students preferred to tangible quality improvement than intangible aspect.

PERAN TEKNOLOGI KOMUNIKASI DALAM INTERAKSI AYAH DAN ANAK STUDI KASUS: INTERAKSI AYAH DAN ANAK MELALUI SMARTPHONE

Directory of Open Access Journals (Sweden)

Detania Savitri

2016-02-01

Fungsi ayah dalam keluarga adalah sebagai pencari nafkah untuk memenuhi kebutuhan keluarga, sementara ibu berfungsi dalam mendidik anak. Ayah yang bekerja penuh waktu akan berkurang interaksinya dengan anak. Disisi lain, teknologi komunikasi diciptakan untuk mempermudah interaksi antar individu. Penelitian ini ingin mengetahui apakah smartphone dapat meningkatkan intensitas kedekatan interaksi antara ayah dan anak. Selain itu, penelitian ini juga ingin mengetahui apakah ayah dapat memberikan sosialisasi kepada anak melalui smartphone dan mengontrol keseharian anak. Artikel ini menggunakan perspektif fungsionalis. Pendekatan kualitatif digunakan oleh penulis dengan mewawancarai tiga ayah dan tiga anak berusia 20 tahun ke atas yang sama-sama menggunakan smartphone di kota Depok. Temuan yang diperoleh penulis yaitu smartphone dapat merubah interaksi ayah dengan anak, dan ayah dapat memberikan kontrol sosial kepada anak dalam interaksi melalui smartphone. Dalam interaksi ayah dan anak, smartphone juga dapat digunakan ayah untuk mensosialisasikan nilai-nilai kepada anak.

77 FR 64399 - Order of Succession for HUD Region VI

Science.gov (United States)

2012-10-19

... Region VI AGENCY: Office of Field Policy and Management, HUD. ACTION: Notice of Order of Succession... its Field Offices (Region VI). This Order of Succession supersedes all previous Orders of Succession for HUD Region VI. DATES: Effective Date: October 9, 2012. FOR FURTHER INFORMATION CONTACT: Lawrence D...

Extraction behavior of uranium(VI) with polyurethane foam

International Nuclear Information System (INIS)

Tingchia Huang; Donghwang Chen; Muchang Shieh; Chingtsven Huang

1992-01-01

The extraction of uranium(VI) from aqueous solution with polyether-based polyurethane (PU) foam was studied. The effects of the kinds and concentrations of nitrate salts, uranium(VI) concentration, temperature, nitric acid concentration, pH, the content of poly(ethylene oxide) in the polyurethane foam, and the ratio of PU foam weight and solution volume on the extraction of uranium(VI) were investigated. The interferences of fluoride and carbonate ions on the extraction of uranium(VI) were also examined, and methods to overcome both interferences were suggested. It was found that no uranium was extracted in the absence of a nitrate salting-out agent, and the extraction behaviors of uranium(IV) with polyurethane foam could be explained in terms of an etherlike solvent extraction mechanism. In addition, the percentage extraction of a multiple stage was also estimated theoretically

PENGEMBANGAN PROFESIONALITAS BERKELANJUTAN GURU BERSERTIFIKAT PENDIDIK DI SMK RUMPUN TEKNOLOGI

Directory of Open Access Journals (Sweden)

Sujianto Sujianto

2013-07-01

Full Text Available Continuous development of certified teachers in vocational high school tech­no­logy clump. The purpose of this study is to describe the continuing professionality deve­lop­ment of teachers certifiedcertified teachers through investments investing in self-development educators, scientific publications, and innovative work wetherboth independently, in groups, or insti­tutionalizedinsti­tutionally. This research uses a descriptive quantitative study design study, with and  a the research subjects are who is certified vocational teachers educators asin Malang Raya. The Research research instruments used in this study are questionnaires and interview guides. The results of this study indi­cate that continuing professionality development of certified teachers certified in vocational educators high school clumps technology clump is still relatively low, most teachers only are categorized in the categories category of sometimes doing self-development investments, scientific publications, and innovative works. Tujuan penelitian ini untuk mendeskripsikan pengembangan profesionalitas berkelanjutan guru bersertifikat pendidik melalui investasi pengembangan diri, publi­kasi ilmiah, dan karya inovatif baik secara mandiri, berkelompok, atau melembaga. Penelitian ini menggunakan rancangan penelitian deskriptif kuantitatif, dengan subjek penelitian guru kejuruan bersertifikat pendidik se-Malang Raya. Instrumen penelitian menggunakan angket dan pedoman wawancara. Hasil penelitian ini menunjukkan bahwa pengembangan profesionalitas berkelanjutan guru berser­tifikat pendidik di SMK rumpun teknologi se-Malang Raya masih tergolong rendah, sebagian besar guru hanya kadang-kadang me­lakukan investasi pengembangan diri, publikasi ilmiah, dan membuat karya inovatif.

Vi-CRM 197 as a new conjugate vaccine against Salmonella Typhi.

Science.gov (United States)

Micoli, F; Rondini, S; Pisoni, I; Proietti, D; Berti, F; Costantino, P; Rappuoli, R; Szu, S; Saul, A; Martin, L B

2011-01-17

An efficacious, low cost vaccine against typhoid fever, especially for young children, would make a major impact on disease burden in developing countries. The virulence capsular polysaccharide of Salmonella Typhi (Vi) coupled to recombinant mutant Pseudomonas aeruginosa exoprotein A (Vi-rEPA) has been shown to be highly efficacious. We investigated the use of carrier proteins included in infant vaccines, standardized the conjugation process and developed key assays required for routine lot release at production scale. Vi from a BSL1 organism, Citrobacter freundii, strain WR7011, was used as an alternative to Vi from S. Typhi. We showed that Vi conjugated to CRM(197), a non-toxic mutant of diphtheria toxin, widely used in commercial vaccines, was produced at high yield. Vi-CRM(197) proved immunogenic in animal studies, even without adjuvant. Thus, Vi-CRM(197) appears to be a suitable candidate for the development of a commercially viable, effective typhoid vaccine for developing countries. Copyright © 2010 Elsevier Ltd. All rights reserved.

The adsorption ability of Cr(VI) on sawdust–polyaniline nanocomposite

International Nuclear Information System (INIS)

Binh Phan, Thi; Que Do, Ngoc; Thanh Thuy Mai, Thi

2010-01-01

The results of this study of sawdust–polyaniline nanocomposite synthesized by a chemical method for Cr(VI) treatment in the environment are presented. Cr(VI) adsorption on a composite was determined by colorimetry. The results showed that sawdust–polyaniline composite synthesized with an aniline:sawdust ratio equal to 0.5 had an adsorption degree of 21.4 mg g −1 and adsorbed nearly 99% of the Cr(VI) after 2 h. The composite could be used for the adsorption of Cr(VI) from waste water. The Cr(VI) adsorption ability of the composite slightly depends on the pH value of the medium. The adsorption is fast during the first half hour and then the rate decreases

Testing of ENDF/B-VI data for shielding applications

International Nuclear Information System (INIS)

Ingersoll, D.T.

1995-01-01

Version VI of the U.S. Evaluated Nuclear Data File (END/B-VI) was released for open distribution in 1990 after an extensive multiyear, multilaboratory evaluation effort coordinated by the Cross Section Evaluation Working Group (CSEWG). More than 75 of the 320 evaluations contained in the library are new for Version VI, including many relatively important nuclides and many with substantial changes to the cross-section data. Also, several important changes were made to the basic data formats for Version VI to permit better representation of the data and to allow additional types of data. Although these format changes yielded improved evaluations, they hindered processing of the data for use in applications codes and delayed the timely integral testing of the data. It has been only during the past year that significant integral testing of END/B-VI data has been achieved. The results and conclusions from some of these efforts are summarized in the following paragraphs

Photoreduction of chromium(VI) in the presence of algae, Chlorella vulgaris

International Nuclear Information System (INIS)

Deng Lin; Wang Hongli; Deng Nansheng

2006-01-01

In this thesis, the photochemical reduction of hexavalent chromium Cr(VI) in the presence of algae, Chlorella vulgaris, was investigated under the irradiation of metal halide lamps (λ=365nm, 250W). The affecting factors of photochemical reduction were studied in detail, such as exposure time, initial Cr(VI) concentration, initial algae concentration and pH. The rate of Cr(VI) photochemical reduction increased with algae concentration increasing, exposure time increasing, initial Cr(VI) concentration decreasing and the decrease of pH. When pH increased to 6, the rate of Cr(VI) photochemical reduction nearly vanished. When initial Cr(VI) concentration ranged from 0.4 to 1.0mgL -1 and initial algae concentration ranged from ABS algae (the absorbency of algae)=0.025 to ABS algae =0.180, According to the results of kinetic analyses, the kinetic equation of Cr(VI) photochemical reduction in aqueous solution with algae under 250W metal halide lamps was V 0 =kC 0 0.1718 A algae 0.5235 (C 0 was initial concentration of Cr(VI); A algae was initial concentration of algae) under the condition of pH 4

Importance of c-Type cytochromes for U(VI reduction by Geobacter sulfurreducens

Directory of Open Access Journals (Sweden)

Leang Ching

2007-03-01

Full Text Available Abstract Background In order to study the mechanism of U(VI reduction, the effect of deleting c-type cytochrome genes on the capacity of Geobacter sulfurreducens to reduce U(VI with acetate serving as the electron donor was investigated. Results The ability of several c-type cytochrome deficient mutants to reduce U(VI was lower than that of the wild type strain. Elimination of two confirmed outer membrane cytochromes and two putative outer membrane cytochromes significantly decreased (ca. 50–60% the ability of G. sulfurreducens to reduce U(VI. Involvement in U(VI reduction did not appear to be a general property of outer membrane cytochromes, as elimination of two other confirmed outer membrane cytochromes, OmcB and OmcC, had very little impact on U(VI reduction. Among the periplasmic cytochromes, only MacA, proposed to transfer electrons from the inner membrane to the periplasm, appeared to play a significant role in U(VI reduction. A subpopulation of both wild type and U(VI reduction-impaired cells, 24–30%, accumulated amorphous uranium in the periplasm. Comparison of uranium-accumulating cells demonstrated a similar amount of periplasmic uranium accumulation in U(VI reduction-impaired and wild type G. sulfurreducens. Assessment of the ability of the various suspensions to reduce Fe(III revealed no correlation between the impact of cytochrome deletion on U(VI reduction and reduction of Fe(III hydroxide and chelated Fe(III. Conclusion This study indicates that c-type cytochromes are involved in U(VI reduction by Geobacter sulfurreducens. The data provide new evidence for extracellular uranium reduction by G. sulfurreducens but do not rule out the possibility of periplasmic uranium reduction. Occurrence of U(VI reduction at the cell surface is supported by the significant impact of elimination of outer membrane cytochromes on U(VI reduction and the lack of correlation between periplasmic uranium accumulation and the capacity for uranium

Cr(III) reactivity and foot dermatitis in Cr(VI) positive patients

DEFF Research Database (Denmark)

Hansen, Malene Barré; Menné, Torkil; Johansen, Jeanne Duus

2006-01-01

Chromium allergy has become synonymous with Cr(VI) allergy. However, real exposure to chromium from leather products may include both Cr(III) and Cr(VI). In this study, we investigate the reactivity to both Cr(VI) and Cr(III) in consecutive patients to analyse the relation between foot eczema/leather...... to Cr(III). The increased risk was not due to a higher degree of sensitivity to Cr(VI). Leather was reported most frequently as the suspected cause of chromium dermatitis (54%). However, Cr(VI) allergics having foot eczema and positive or doubtful Cr(III) reactions often had positive reactions to other...

An experimental study on the sorption of U(VI) onto granite

International Nuclear Information System (INIS)

Baik, Min Hoon; Hahn, Pil Soo

2002-01-01

The sorption of U(VI) on a domestic granite is studied as a function of experimental conditions such as contact time, solution-solid ratio, ionic strength, and pH using a batch procedure. The distribution coefficients, K d 's, of U(VI) are about 1-100mL/g depending on the experimental conditions. The sorption of U(VI) onto granite particles is greatly dependent upon the contact time, solution-solid ratio, and pH, but very little is dependent on the ionic strength. It is noticed that an U(VI)-carbonato ternary surface complex can be formed in the neutral range of pH. In the alkaline range of pH above 7, U(VI) sorption onto granite particles is greatly decreased due to the formation of anionic U(VI)-carbonato aqueous complexes

Simultaneous Cr(VI) bio-reduction and methane production by anaerobic granular sludge.

Science.gov (United States)

Hu, Qian; Sun, Jiaji; Sun, Dezhi; Tian, Lan; Ji, Yanan; Qiu, Bin

2018-08-01

Wastewater containing toxic hexavalent chromium (Cr(VI)) were treated with well-organized anaerobic granular sludge in this study. Results showed that the anaerobic granular sludge rapidly removed Cr(VI), and 2000 µg·L -1 Cr(VI) was completely eliminated within 6 min, which was much faster than the reported duration of removal by reported artificial materials. Sucrose added as a carbon source acted as an initial electron donor to reduce Cr(VI) to Cr(III). This process was considered as the main mechanism of Cr(VI) removal. Methane production by anaerobic granular sludge was improved by the addition of Cr(VI) at a concentration lower than 500 µg·L -1 . Anaerobic granular sludge had a well-organized structure, which presented good resistance against toxic Cr(VI). Trichoccus accelerated the degradation of organic substances to generate acetates with a low Cr(VI) concentration, thereby enhancing methane production by acetotrophic methanogens. Copyright © 2018 Elsevier Ltd. All rights reserved.

Re-examination of immune response and estimation of anti-Vi IgG protective threshold against typhoid fever-based on the efficacy trial of Vi conjugate in young children.

Science.gov (United States)

Szu, Shousun C; Klugman, Keith P; Hunt, Steven

2014-04-25

The capsular polysaccharide of Salmonella enterica serovar Typhi, Vi antigen, is an essential virulence factor and a protective antigen. Similar to other polysaccharide vaccines, the protective action of Vi, both to the polysaccharide alone or when presented as a conjugate, is mediated by serum IgG Vi antibodies. The evaluation of Vi capsular polysaccharide based vaccines to prevent typhoid fever would be significantly facilitated by the identification of a "protective level" of serum antibodies to Vi antigen. The protective level of anti-Vi IgG against typhoid fever was derived from the protective efficacy and immune response of a Vi-rEPA conjugate vaccine efficacy trial. The estimation was derived by two methods: correlation of the percent efficacy and the antibody distribution profile in the vaccine group at a given period of observation, and use of the relative ratio of anti-Vi IgG levels between the vaccine and placebo groups greater or equal to the Relative Risk of typhoid fever used in the efficacy determination. Both methods predicted a similar range of a minimum protective level of anti-Vi IgG between 1.4 and 2.0μg/ml (short term threshold). When applying a protective threshold of 10μg/ml at 6 months post immunization, an IgG level in excess of 1.4μg/ml was achieved by 90% of children at 46 months post immunization, consistent with an 89% level of protection over the duration of the study. We thus suggest that the proportion of children with Vi IgG>10μg/ml (long term threshold) 6 months after immunization may reflect the proportion protected over at least a 4 year period. The current assignment of an anti-Vi IgG protective level may be of value when evaluating vaccine performance of future Vi conjugate vaccines. Published by Elsevier Ltd.

Factors affecting the adsorption of chromium (VI) on activated carbon

Energy Technology Data Exchange (ETDEWEB)

Yavuz, R.; Orbak, I.; Karatepe, N. [Istanbul Technical University, Istanbul (Turkey)

2006-09-15

The aim of this investigation was to determine the adsorption behavior of chromium (VI) on two different activated carbon samples produced from Tuncbilek lignite. The effects of the initial chromium (VI) concentration (250-1000 mg/L), temperature (297-323 K) and pH (2.0-9.5) on adsorption were investigated systematically. The effectiveness of the parameters on chromium adsorption was found to be in the order of pH, the initial Cr(VI) concentration and the temperature. Increasing the pH from 2.0 to 9.5 caused a decrease in adsorption. However, the adsorption was increased by increasing the initial Cr(VI) concentration and temperature. The multilinear mathematical model was also developed to predict the Cr(VI) adsorption on activated carbon samples within the experimental conditions.

Analytical applications of N-phenyl-n-butyro hydroxamic and N-p-tolyl-n-butyro hydroxamic acids towards chromium (VI), copper (II), iron (III) and uranium (VI)

International Nuclear Information System (INIS)

Elkhadir, A. Y. F.

2001-05-01

Two aliphatic hydroxamic acids were prepared; N-phenyl-n-butyro hydroxamic acid and N-p-tolyl-n-butyro hydroxamic acid, by the reaction of β-phenylhydroxylamine and p-tolyl hydroxylamine with n-butyryl chloride. The acids were identified by: their melting points, characteristic reactions with acidic solutions of vanadium (V) and iron (III), infrared spectroscopy, nitrogen content and molecular weight determination. The extractability of these acids towards Cr (VI), Cu (II), Fe (III) and U (VI) were investigated at different pH values and molar acid concentrations. N-phenyl-n- butyro hydroxamic acid has a maximum extraction (98.80%) for Cr (VI) at 4 M H 2 SO 4 , (83.25%) for Cu (II) at pH 6, (99.17%) for Fe (III) at pH 5 and (99.76%) at 4 M HNO 3 for U (VI) respectively. N-p-tolyl-n-butyro hydroxamic acid has a maximum extraction (98.40%) for Cr (VI)at 4 M H 2 SO 4 , (81.30%) for Cu (II) at pH 6, (92.80%) for Fe (III) at pH 5 and (99.64%) for U (VI) at 4 M HNO 3 , respectively. The ratios of the metal to ligands were determined by job method (continuous variation method) and were found to be 1:2 for Cr (VI) and U (VI). (Author)

Analytical applications of N-phenyl-n-butyro hydroxamic and N-p-tolyl-n-butyro hydroxamic acids towards chromium (VI), copper (II), iron (III) and uranium (VI)

Energy Technology Data Exchange (ETDEWEB)

Elkhadir, A Y. F. [Department of Chemistry, Faculty of Science, University of Khartoum, Khartoum (Sudan)

2001-05-01

Two aliphatic hydroxamic acids were prepared; N-phenyl-n-butyro hydroxamic acid and N-p-tolyl-n-butyro hydroxamic acid, by the reaction of {beta}-phenylhydroxylamine and p-tolyl hydroxylamine with n-butyryl chloride. The acids were identified by: their melting points, characteristic reactions with acidic solutions of vanadium (V) and iron (III), infrared spectroscopy, nitrogen content and molecular weight determination. The extractability of these acids towards Cr (VI), Cu (II), Fe (III) and U (VI) were investigated at different pH values and molar acid concentrations. N-phenyl-n- butyro hydroxamic acid has a maximum extraction (98.80%) for Cr (VI) at 4 M H{sub 2}SO{sub 4}, (83.25%) for Cu (II) at pH 6, (99.17%) for Fe (III) at pH 5 and (99.76%) at 4 M HNO{sub 3} for U (VI) respectively. N-p-tolyl-n-butyro hydroxamic acid has a maximum extraction (98.40%) for Cr (VI)at 4 M H{sub 2} SO{sub 4}, (81.30%) for Cu (II) at pH 6, (92.80%) for Fe (III) at pH 5 and (99.64%) for U (VI) at 4 M HNO{sub 3}, respectively. The ratios of the metal to ligands were determined by job method (continuous variation method) and were found to be 1:2 for Cr (VI) and U (VI). (Author)

Photoreduction of chromium(VI) in the presence of algae, Chlorella vulgaris

Energy Technology Data Exchange (ETDEWEB)

Deng Lin [School of Resources and Environmental Science, Wuhan University, Wuhan 430072 (China); Wang Hongli [School of Resources and Environmental Science, Wuhan University, Wuhan 430072 (China); Deng Nansheng [School of Resources and Environmental Science, Wuhan University, Wuhan 430072 (China)]. E-mail: nsdengwhu@163.com

2006-11-16

In this thesis, the photochemical reduction of hexavalent chromium Cr(VI) in the presence of algae, Chlorella vulgaris, was investigated under the irradiation of metal halide lamps ({lambda}=365nm, 250W). The affecting factors of photochemical reduction were studied in detail, such as exposure time, initial Cr(VI) concentration, initial algae concentration and pH. The rate of Cr(VI) photochemical reduction increased with algae concentration increasing, exposure time increasing, initial Cr(VI) concentration decreasing and the decrease of pH. When pH increased to 6, the rate of Cr(VI) photochemical reduction nearly vanished. When initial Cr(VI) concentration ranged from 0.4 to 1.0mgL{sup -1} and initial algae concentration ranged from ABS{sub algae} (the absorbency of algae)=0.025 to ABS{sub algae}=0.180, According to the results of kinetic analyses, the kinetic equation of Cr(VI) photochemical reduction in aqueous solution with algae under 250W metal halide lamps was V{sub 0}=kC{sub 0}{sup 0.1718}A{sub algae}{sup 0.5235} (C{sub 0} was initial concentration of Cr(VI); A{sub algae} was initial concentration of algae) under the condition of pH 4.

CoQ10 Deficiency May Indicate Mitochondrial Dysfunction in Cr(VI Toxicity

Directory of Open Access Journals (Sweden)

Xiali Zhong

2017-04-01

Full Text Available To investigate the toxic mechanism of hexavalent chromium Cr(VI and search for an antidote for Cr(VI-induced cytotoxicity, a study of mitochondrial dysfunction induced by Cr(VI and cell survival by recovering mitochondrial function was performed. In the present study, we found that the gene expression of electron transfer flavoprotein dehydrogenase (ETFDH was strongly downregulated by Cr(VI exposure. The levels of coenzyme 10 (CoQ10 and mitochondrial biogenesis presented by mitochondrial mass and mitochondrial DNA copy number were also significantly reduced after Cr(VI exposure. The subsequent, Cr(VI-induced mitochondrial damage and apoptosis were characterized by reactive oxygen species (ROS accumulation, caspase-3 and caspase-9 activation, decreased superoxide dismutase (SOD and ATP production, increased methane dicarboxylic aldehyde (MDA content, mitochondrial membrane depolarization and mitochondrial permeability transition pore (MPTP opening, increased Ca2+ levels, Cyt c release, decreased Bcl-2 expression, and significantly elevated Bax expression. The Cr(VI-induced deleterious changes were attenuated by pretreatment with CoQ10 in L-02 hepatocytes. These data suggest that Cr(VI induces CoQ10 deficiency in L-02 hepatocytes, indicating that this deficiency may be a biomarker of mitochondrial dysfunction in Cr(VI poisoning and that exogenous administration of CoQ10 may restore mitochondrial function and protect the liver from Cr(VI exposure.

As duas naturezas de Lévi-Strauss

Directory of Open Access Journals (Sweden)

Philippe Descola

2011-11-01

Full Text Available Aborda-se aqui a complexidade do status do par conceitual natureza e cultura no pensamento de Lévi-Strauss. Ao mesmo tempo ferramenta de análise, cena filosófica dos primórdios e antinomia a superar, revisita-se os diferentes usos e significados na obra de Lévi-Strauss do conceito de natureza e sua relação com o de cultura. Mostra-se como é possível reconhecer na obra de Lévi-Strauss dois conceitos de natureza: por um lado, uma natureza que se opõe à cultura num programa científico formulado em termos classicamente dualistas e, por outro, uma teoria do conhecimento decididamente monista que considera o espírito como parte e produto desse mesmo mundo. Argumenta-se que se o dualismo entre cultura e natureza fundou o pensamento estruturalista de Lévi-Strauss, é na própria obra deste que encontramos os argumentos e meios de superá-lo. A vocação do estruturalismo na antropologia de hoje, no entanto, é de ir mais longe neste caminho do que foi o próprio fundador.

Procedure for plutonium determination using Pu(VI) spectra

International Nuclear Information System (INIS)

Walker, L.F.; Temer, D.J.; Jackson, D.D.

1996-01-01

This document describes a simple spectrophotometric method for determining total plutonium in nitric acid solutions based on the spectrum of Pu(VI). Plutonium samples in nitric acid are oxidized to Pu(VI) with Ce(IV) and the net absorbance at the 830 nm peak is measured

Blockchain to be - Bitcoin not to be?

DEFF Research Database (Denmark)

Bechmann, Ken L.

2018-01-01

Parallelt med meget store stigninger og fald i kursen på Bitcoin har der været meget opmærksomhed rettet mod anvendelsesmuligheder af kryptovalutaer og den underliggende blockchain-teknologi. Dette nummer af Finans/Invest bidrager til denne diskussion gennem flere artikler. Denne leder drister sig....... Omvendt synes der at være så mange mulige anvendelser af blockchain-teknologien, at vi her nok kun så småt er begyndt at se toppen af isbjerget....

Synthesis of surface Cr (VI)-imprinted magnetic nanoparticles for selective dispersive solid-phase extraction and determination of Cr (VI) in water samples.

Science.gov (United States)

Qi, Xue; Gao, Shuang; Ding, Guosheng; Tang, An-Na

2017-01-01

A facile, rapid and selective magnetic dispersed solid-phase extraction (dSPE) method for the extraction and enrichment of Cr (VI) prior to flame atomic absorption spectrometry (AAS) was introduced. For highly selective and efficient extraction, magnetic Cr (VI)-imprinted nanoparticles (Fe 3 O 4 @ Cr (VI) IIPs) were prepared by hyphenating surface ion-imprinted with sol-gel techniques. In the preparation process, chromate (Cr(VI)) was used as the template ion; vinylimidazole and 3-aminopropyltriethoxysilane were selected as organic functional monomer and co-monomer respectively. Another reagent, methacryloxypropyltrimethoxysilane was adopted as coupling agent to form the stable covalent bonding between organic and inorganic phases. The effects of various parameters on the extraction efficiency, such as pH of sample solution, the amount of adsorbent, extraction time, the type and concentration of eluent were systematically investigated. Furthermore, the thermodynamic and kinetic properties of the adsorption process were studied to explore the internal adsorption mechanism. Under optimized conditions, the preconcentration factor, limit of detection and linear range of the established dSPE-AAS method for Cr (VI) were found to be 98, 0.29μgL -1 and 4-140μgL -1 , respectively. The developed method was also successfully applied to the analysis of Cr (VI) in different water samples with satisfactory results, proving its reliability and feasibility in real sample analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

Proceeding of the Fifth Scientific Presentation on Nuclear Fuel Cycle: Development of Nuclear Fuel Cycle Technology in Third Millennium; Presentasi Ilmiah Daur Bahan Bakar Nuklir V: Pengembangan Teknologi Daur Bahan Bakar Nuklir Dalam Menyongsong Milenium Ketiga

Energy Technology Data Exchange (ETDEWEB)

Suripto, A; Sastratenaya, A S; Sutarno, D [National Atomic Energy Agency, Serpong (Indonesia); and others

2000-03-08

The proceeding contains papers presented in the Fifth Scientific Presentation on Nuclear Fuel Element Cycle with theme of Development of Nuclear Fuel Cycle Technology in Third Millennium, held on 22 February in Jakarta, Indonesia. These papers were divided by three groups that are technology of exploration, processing, purification and analysis of nuclear materials; technology of nuclear fuel elements and structures; and technology of waste management, safety and management of nuclear fuel cycle. There are 35 papers indexed individually. (id)

Modelling Cr(VI) removal by a combined carbon-activated sludge system

International Nuclear Information System (INIS)

Orozco, A. Micaela Ferro; Contreras, Edgardo M.; Zaritzky, Noemi E.

2008-01-01

The combined carbon-activated sludge process has been proposed as an alternative to protect the biomass against toxic substances in wastewaters; however, the information about the effect of powdered-activated carbon (PAC) addition in activated sludge reactors for the treatment of wastewaters containing Cr(VI) is limited. The objectives of the present study were: (a) to evaluate the removal of hexavalent chromium by (i) activated sludge microorganisms in aerobic batch reactors, (ii) powdered-activated carbon, and (iii) the combined action of powdered-activated carbon and biomass; (b) to propose mathematical models that interpret the experimental results. Different Cr(VI) removal systems were tested: (S1) biomass (activated sludge), (S2) PAC, and (S3) the combined activated carbon-biomass system. A Monod-based mathematical model was used to describe the kinetics of Cr(VI) removal in the system S1. A first-order kinetics with respect to Cr(VI) and PAC respectively, was proposed to model the removal of Cr(VI) in the system S2. Cr(VI) removal in the combined carbon-biomass system (S3) was faster than both Cr(VI) removal using PAC or activated sludge individually. Results showed that the removal of Cr(VI) using the activated carbon-biomass system (S3) was adequately described by combining the kinetic equations proposed for the systems S1 and S2

A CMOS rail-to-rail linear VI-converter

NARCIS (Netherlands)

Vervoort, P.P.; Vervoort, P.P.; Wassenaar, R.F.

1995-01-01

A linear CMOS VI-converter operating in strong inversion with a common-mode input range from the negative to the positive supply rail is presented. The circuit consists of three linear VI-converters based on the difference of squares principle. Two of these perform the actual V to I conversion,

Ternary uranium(VI) carbonato humate complex studied by cryo-TRLFS

International Nuclear Information System (INIS)

Steudtner, R.; Sachs, S.; Schmeide, K.; Brendler, V.; Bernhard, G.

2011-01-01

The complex formation of U(VI) with humic acid (HA) in the presence of carbonate was studied by time-resolved laser-induced fluorescence spectroscopy at low temperature (cryo-TRLFS) at pH 8.5. In the presence of HA, a decrease of the luminescence intensity of U(VI) and no shift of the emission band maxima in comparison to the luminescence spectrum of the UO 2 (CO 3 ) 3 4- complex, the dominating U(VI) species under the applied experimental conditions in the absence of HA, was observed. The formation of a ternary U(VI) carbonato humate complex of the type UO 2 (CO 3 ) 2 HA(II) 4- starting from UO 2 (CO 3 ) 3 4- was concluded from the luminescence data. For this complex a complex stability constant of log K=2.83 ± 0.17 was determined. Slope analysis resulted in a slope of 1.12 ± 0.11, which verifies the postulated complexation reaction. The results agree very well with literature data. Speciation calculations show that the formation of the ternary U(VI) carbonato humate complex can significantly influence the U(VI) speciation under environmental conditions. (orig.)

THE SURPRISINGLY CONSTANT STRENGTH OF O VI ABSORBERS OVER COSMIC TIME

International Nuclear Information System (INIS)

Fox, Andrew J.

2011-01-01

O VI absorption is observed in a wide range of astrophysical environments, including the local interstellar medium, the disk and halo of the Milky Way, high-velocity clouds, the Magellanic Clouds, starburst galaxies, the intergalactic medium (IGM), damped Lyα systems, and gamma-ray-burst host galaxies. Here, a new compilation of 775 O VI absorbers drawn from the literature is presented, all observed at high resolution (instrumental FWHM ≤ 20 km s -1 ) and covering the redshift range z = 0-3. In galactic environments [log N(H I) ∼> 20], the mean O VI column density is shown to be insensitive to metallicity, taking a value log N(O VI) ∼ 14.5 for galaxies covering the range -1.6 ∼ 4 K) clouds and hot (∼10 6 K) plasma, although many such layers would have to be intersected by a typical galaxy-halo sight line to build up the characteristic galactic N(O VI). The alternative, widely used model of single-phase photoionization for intergalactic O VI is ruled out by kinematic evidence in the majority of IGM O VI components at low and high redshift.

Reduction of trace quantities of chromium(VI by strong acids

Directory of Open Access Journals (Sweden)

Pezzin Sérgio H

2004-01-01

Full Text Available The chemical behavior of Cr(VI at low concentrations (10-4 to 10-7 mol L-1 in several strong acids was studied using high specific activity 51Cr(VI as a tracer. The speciation of the products from these systems was carried out by ion exchange chromatography with stepwise elution. The results show that trace quantities of Cr(VI, monitored by means of radiochromium (51Cr, are reduced in the presence of mineral acids such as perchloric, hydrochloric, hydrofluoric, sulfuric, nitric and trifluoromethanesulfonic acids, even in the absence of conventional reducing agents, producing different measureable Cr(III species, depending on the acid anion. Detailed studies of the reduction of low concentrations of Cr(VI with nitric acid have shown that the relative rate of reduction increases as the concentration of the acid increases or as the concentration of the Cr(VI decreases.

Estudio de inmunogenicidad de la vacuna antitifoídica cubana de polisacárido Vi vax-TyVi® en ratones

Directory of Open Access Journals (Sweden)

Juan Carlos Ramírez

2006-08-01

Full Text Available Salmonella enterica serovar Typhi es un microorganismo que provoca más de 16 millones de casos de fiebre tifoidea con aproximadamente 600 000 muertes al año en todo el mundo. Dentro de las vacunas antitifoídicas la de polisacárido capsular Vi ha encontrado, gracias a sus incuestionables ventajas, una gran aceptación entre productores y consumidores. El presente trabajo aborda el estudio de inmunogenicidad de la vacuna antitifoídica cubana de polisacárido Vi vax-TyViâ en ratones. El estudio estuvo conformado por un grupo control no inoculado y un segundo grupo que recibió 0,05 mL de la vacuna por vía intramuscular. Se tomaron muestras de sangre a los -3, 7, 14, 21, 28, 42, 56 y 84 días. La actividad de anticuerpos IgG antipolisacárido Vi de los sueros individuales fue determinada por ELISA. Los datos fueron analizados por grupo y por sexo y se calculó el porcentaje de seroconversión, considerándose respondedor aquel animal que al menos aumentara en cuatro veces su título inicial. La respuesta de anticuerpos inducida por la vacuna mostró un aumento notable de los títulos de IgG antipolisacárido Vi en el grupo vacunado (100% de seroconversión, mientras que el grupo control no incrementó sus niveles mínimos iniciales (0% de respondedores. Aunque más dispersa, la respuesta de anticuerpos antiVi fue significativamente mayor en las hembras que en los machos.

Synthesis, structure and properties of oxo- and dioxochloride complexes of molybdenum(VI) and tungsten(VI) with 8-oxyquinoline

International Nuclear Information System (INIS)

Abramenko, V.L.; Sergienko, V.S.; Egorova, O.A.

2005-01-01

Complexes of oxo- and dioxochlorides of molybdenum(VI) and tungsten(VI) with 8-oxyquinoline of molecular and intracomplex type are synthesized and studied by the method of IR spectroscopy. The complexes have octahedral structure. It is proposed that 8-oxyquinoline in molecular complexes is coordinated by central atom through nitrogen atom of heterocycle, but in intracomplex compounds - through heterocyclic nitrogen atom and oxygen atom of deprotonated OH-group. Thermal stability of the complexes is studied [ru

Quantifying Cr(VI) Production and Export from Serpentine Soil of the California Coast Range.

Science.gov (United States)

McClain, Cynthia N; Fendorf, Scott; Webb, Samuel M; Maher, Kate

2017-01-03

Hexavalent chromium (Cr(VI)) is generated in serpentine soils and exported to surface and groundwaters at levels above health-based drinking water standards. Although Cr(VI) concentrations are elevated in serpentine soil pore water, few studies have reported field evidence documenting Cr(VI) production rates and fluxes that govern Cr(VI) transport from soil to water sources. We report Cr speciation (i) in four serpentine soil depth profiles derived from the California Coast Range serpentinite belt and (ii) in local surface waters. Within soils, we detected Cr(VI) in the same horizons where Cr(III)-minerals are colocated with biogenic Mn(III/IV)-oxides, suggesting Cr(VI) generation through oxidation by Mn-oxides. Water-extractable Cr(VI) concentrations increase with depth constituting a 7.8 to 12 kg/km 2 reservoir of Cr(VI) in soil. Here, Cr(VI) is produced at a rate of 0.3 to 4.8 kg Cr(VI)/km 2 /yr and subsequently flushed from soil during water infiltration, exporting 0.01 to 3.9 kg Cr(VI)/km 2 /yr at concentrations ranging from 25 to 172 μg/L. Although soil-derived Cr(VI) is leached from soil at concentrations exceeding 10 μg/L, due to reduction and dilution during transport to streams, Cr(VI) levels measured in local surface waters largely remain below California's drinking water limit.

Chromium (VI) biosorption properties of multiple resistant bacteria isolated from industrial sewerage.

Science.gov (United States)

Oyetibo, Ganiyu Oladunjoye; Ilori, Matthew Olusoji; Obayori, Oluwafemi Sunday; Amund, Olukayode Oladipo

2013-08-01

Chromium (VI) [Cr (VI)] biosorption by four resistant autochthonous bacterial strains was investigated to determine their potential for use in sustainable marine water-pollution control. Maximum exchange between Cr (VI) ions and protons on the cells surfaces were at 30-35 °C, pH 2.0 and 350-450 mg/L. The bacterial strains effectively removed 79.0-90.5 % Cr (VI) ions from solution. Furthermore, 85.3-93.0 % of Cr (VI) ions were regenerated from the biomasses, and 83.4-91.7 % of the metal was adsorbed when the biomasses was reused. Langmuir isotherm performed better than Freundlich isotherm, depicting that Cr (VI) affinity was in the sequence Rhodococcus sp. AL03Ni > Burkholderia cepacia AL96Co > Corynebacterium kutscheri FL108Hg > Pseudomonas aeruginosa CA207Ni. Biosorption isotherms confirmed that Rhodococcus sp. AL03Ni was a better biosorbent with a maximum uptake of 107.46 mg of Cr (VI) per g (dry weight) of biomass. The results highlight the high potential of the organisms for bacteria-based detoxification of Cr (VI) via biosorption.

Mucopolysaccharidosis VI

Directory of Open Access Journals (Sweden)

Harmatz Paul

2010-04-01

Full Text Available Abstract Mucopolysaccharidosis VI (MPS VI is a lysosomal storage disease with progressive multisystem involvement, associated with a deficiency of arylsulfatase B leading to the accumulation of dermatan sulfate. Birth prevalence is between 1 in 43,261 and 1 in 1,505,160 live births. The disorder shows a wide spectrum of symptoms from slowly to rapidly progressing forms. The characteristic skeletal dysplasia includes short stature, dysostosis multiplex and degenerative joint disease. Rapidly progressing forms may have onset from birth, elevated urinary glycosaminoglycans (generally >100 μg/mg creatinine, severe dysostosis multiplex, short stature, and death before the 2nd or 3rd decades. A more slowly progressing form has been described as having later onset, mildly elevated glycosaminoglycans (generally ARSB gene, located in chromosome 5 (5q13-5q14. Over 130 ARSB mutations have been reported, causing absent or reduced arylsulfatase B (N-acetylgalactosamine 4-sulfatase activity and interrupted dermatan sulfate and chondroitin sulfate degradation. Diagnosis generally requires evidence of clinical phenotype, arylsulfatase B enzyme activity ®, clinical management was limited to supportive care and hematopoietic stem cell transplantation. Galsulfase is now widely available and is a specific therapy providing improved endurance with an acceptable safety profile. Prognosis is variable depending on the age of onset, rate of disease progression, age at initiation of ERT and on the quality of the medical care provided.

Integrated Cr(VI) removal using constructed wetlands and composting.

Science.gov (United States)

Sultana, Mar-Yam; Chowdhury, Abu Khayer Md Muktadirul Bari; Michailides, Michail K; Akratos, Christos S; Tekerlekopoulou, Athanasia G; Vayenas, Dimitrios V

2015-01-08

The present work was conducted to study integrated chromium removal from aqueous solutions in horizontal subsurface (HSF) constructed wetlands. Two pilot-scale HSF constructed wetlands (CWs) units were built and operated. One unit was planted with common reeds (Phragmites australis) and one was kept unplanted. Influent concentrations of Cr(VI) ranged from 0.5 to 10mg/L. The effect of temperature and hydraulic residence time (8-0.5 days) on Cr(VI) removal were studied. Temperature was proved to affect Cr(VI) removal in both units. In the planted unit maximum Cr(VI) removal efficiencies of 100% were recorded at HRT's of 1 day with Cr(VI) concentrations of 5, 2.5 and 1mg/L, while a significantly lower removal rate was recorded in the unplanted unit. Harvested reed biomass from the CWs was co-composted with olive mill wastes. The final product had excellent physicochemical characteristics (C/N: 14.1-14.7, germination index (GI): 145-157%, Cr: 8-10mg/kg dry mass), fulfills EU requirements and can be used as a fertilizer in organic farming. Copyright © 2014 Elsevier B.V. All rights reserved.

Retention of U(VI) onto silica in presence of model organic molecules

International Nuclear Information System (INIS)

Pham, T.T.H.; Mercier-Bion, F.; Drot, R.; Lagarde, G.; Simoni, E.; Lambert, J.

2008-01-01

It is well-known that the organic matter influences the retention of ions onto mineral surfaces. However, the major part of concerned studies implies humic substances and complex solids. Another approach for identifying the sorption mechanisms is possible by studying simpler solids than those present in natural medium. So, silica is chosen as mineral surface because of its abundance in soils and of the presence of Si-O groups in clayey minerals. Uranium (VI) is selected as cation. Simple organic molecules like acetic (one carboxylic group) and oxalic (two carboxylic functions) acids are considered as models of the natural organic matter for understanding their role in the retention of U(VI) onto powders and slides of silica. Binary (organics/silica, U(VI)/silica) and ternary systems (organics/silica/U(VI)) are studied by complementary approaches. Sorption edges as function of pH are obtained by liquid scintillation methods and capillary electrophoresis. Different spectroscopic techniques are used to deduce the interactions between the organic matter and U(VI) sorbed onto the silica whose: Time-Resolved Laser induced Fluorescence Spectroscopy (TRLFS), X-ray Photoelectron Spectroscopy (XPS), Nuclear Microprobe Analysis (NMA). The results of the effect of these model organic molecules onto the U(VI) retention showed a good agreement between the different techniques. Concerning the acetic acid, there are not differences in the sorption percentages of uranyl (see the figure). All these results indicate that the uranyl-acetate complexes stay in the aqueous solution rather than sorbing onto the silica. On the contrary, oxalic acid influences the sorption of U(VI) onto the silica surface. The sorption percentage of U(VI) in the ternary system (oxalic acid/silica/U(VI)) is lower than the binary system (U(VI)/silica) (see the figure). So, the presence of oxalic acid decreases the sorption of U(VI) onto the silica surface. (authors)

Experimental Monitoring of Cr(VI) Bio-reduction Using Electrochemical Geophysics

International Nuclear Information System (INIS)

Birsen Canan; Gary R. Olhoeft; William A. Smith

2007-01-01

Many Department of Energy (DOE) sites are contaminated with highly carcinogenic hexavalent chromium (Cr(VI)). In this research, we explore the feasibility of applying complex resistivity to the detection and monitoring of microbially-induced reduction of hexavalent chromium (Cr(VI)) to a less toxic form (Cr(III)). We hope to measure the change in ionic concentration that occurs during this reduction reaction. This form of reduction promises to be an attractive alternative to more expensive remedial treatment methods. The specific goal of this research is to define the minimum and maximum concentration of the chemical and biological compounds in contaminated samples for which the Cr(VI) - Cr(III) reduction processes could be detected via complex resistivity. There are three sets of experiments, each comprised of three sample columns. The first experiment compares three concentrations of Cr(VI) at the same bacterial cell concentration. The second experiment establishes background samples with, and without, Cr(VI) and bacterial cells. The third experiment examines the influence of three different bacterial cell counts on the same concentration of Cr(VI). A polarization relaxation mechanism was observed between 10 and 50 Hz. The polarization mechanism, unfortunately, was not unique to bio-chemically active samples. Spectral analysis of complex resistivity data, however, showed that the frequency where the phase minimum occurred was not constant for bio-chemically active samples throughout the experiment. A significant shifts in phase minima occurred between 10 to 20 Hz from the initiation to completion of Cr(VI) reduction. This phenomena was quantified using the Cole-Cole model and the Marquardt-Levenberg nonlinear least square minimization method. The data suggests that the relaxation time and the time constant of this relaxation are the Cole-Cole parameters most sensitive to changes in biologically-induced reduction of Cr(VI)

Paisaje del viñedo: patrimonio y recurso

Directory of Open Access Journals (Sweden)

Luis Vicente Elías

2008-01-01

Full Text Available La propuesta de que el paisaje del viñedo sea el complemento a la visita a la bodega, siendo esta el eje del turismo del vino, es el objetivo de este trabajo. Repasando los conceptos variables de patrimonio, llegamos al paisaje del viñedo como recurso, formando parte del patrimonio natural. Pero este no se puede desvincular de los otros aspectos patrimoniales, por lo que la cultura tradicional es el soporte de la tipología de paisaje que queremos proponer y que va contrastar con los nuevos paisajes del viñedo que surgen de las recientes técnicas en los cultivos y de la actual vitivicultura, emparejada con una moderna “cultura del vino”. El análisis de las diversas normativas, que salvaguardan el paisaje y la comprobación del escaso valor legal del paisaje del viñedo, es otro puntal de este trabajo que trata de unir paisaje con cultura tradicional como recursos del Turismo del Vino, integrados en las Rutas del Vino.

Delineation and Diagnostic Criteria of Oral-Facial-Digital Syndrome Type VI

Directory of Open Access Journals (Sweden)

Poretti Andrea

2012-01-01

Full Text Available Abstract Oral-Facial-Digital Syndrome type VI (OFD VI represents a rare phenotypic subtype of Joubert syndrome and related disorders (JSRD. In the original report polydactyly, oral findings, intellectual disability, and absence of the cerebellar vermis at post-mortem characterized the syndrome. Subsequently, the molar tooth sign (MTS has been found in patients with OFD VI, prompting the inclusion of OFD VI in JSRD. We studied the clinical, neurodevelopmental, neuroimaging, and genetic findings in a cohort of 16 patients with OFD VI. We derived the following inclusion criteria from the literature: 1 MTS and one oral finding and polydactyly, or 2 MTS and more than one typical oral finding. The OFD VI neuroimaging pattern was found to be more severe than in other JSRD subgroups and includes severe hypoplasia of the cerebellar vermis, hypoplastic and dysplastic cerebellar hemispheres, marked enlargement of the posterior fossa, increased retrocerebellar collection of cerebrospinal fluid, abnormal brainstem, and frequently supratentorial abnormalities that occasionally include characteristic hypothalamic hamartomas. Additionally, two new JSRD neuroimaging findings (ascending superior cerebellar peduncles and fused thalami have been identified. Tongue hamartomas, additional frenula, upper lip notch, and mesoaxial polydactyly are specific findings in OFD VI, while cleft lip/palate and other types of polydactyly of hands and feet are not specific. Involvement of other organs may include ocular findings, particularly colobomas. The majority of the patients have absent motor development and profound cognitive impairment. In OFD VI, normal cognitive functions are possible, but exceptional. Sequencing of known JSRD genes in most patients failed to detect pathogenetic mutations, therefore the genetic basis of OFD VI remains unknown. Compared with other JSRD subgroups, the neurological findings and impairment of motor development and cognitive functions in OFD

New approach in modeling Cr(VI) sorption onto biomass from metal binary mixtures solutions

Energy Technology Data Exchange (ETDEWEB)

Liu, Chang [College of Environmental Science and Engineering, Anhui Normal University, South Jiuhua Road, 189, 241002 Wuhu (China); Chemical Engineering Department, Escola Politècnica Superior, Universitat de Girona, Ma Aurèlia Capmany, 61, 17071 Girona (Spain); Fiol, Núria [Chemical Engineering Department, Escola Politècnica Superior, Universitat de Girona, Ma Aurèlia Capmany, 61, 17071 Girona (Spain); Villaescusa, Isabel, E-mail: Isabel.Villaescusa@udg.edu [Chemical Engineering Department, Escola Politècnica Superior, Universitat de Girona, Ma Aurèlia Capmany, 61, 17071 Girona (Spain); Poch, Jordi [Applied Mathematics Department, Escola Politècnica Superior, Universitat de Girona, Ma Aurèlia Capmany, 61, 17071 Girona (Spain)

2016-01-15

In the last decades Cr(VI) sorption equilibrium and kinetic studies have been carried out using several types of biomasses. However there are few researchers that consider all the simultaneous processes that take place during Cr(VI) sorption (i.e., sorption/reduction of Cr(VI) and simultaneous formation and binding of reduced Cr(III)) when formulating a model that describes the overall sorption process. On the other hand Cr(VI) scarcely exists alone in wastewaters, it is usually found in mixtures with divalent metals. Therefore, the simultaneous removal of Cr(VI) and divalent metals in binary mixtures and the interactive mechanism governing Cr(VI) elimination have gained more and more attention. In the present work, kinetics of Cr(VI) sorption onto exhausted coffee from Cr(VI)–Cu(II) binary mixtures has been studied in a stirred batch reactor. A model including Cr(VI) sorption and reduction, Cr(III) sorption and the effect of the presence of Cu(II) in these processes has been developed and validated. This study constitutes an important advance in modeling Cr(VI) sorption kinetics especially when chromium sorption is in part based on the sorbent capacity of reducing hexavalent chromium and a metal cation is present in the binary mixture. - Highlights: • A kinetic model including Cr(VI) reduction, Cr(VI) and Cr(III) sorption/desorption • Synergistic effect of Cu(II) on Cr(VI) elimination included in the model • Model validation by checking it against independent sets of data.

New approach in modeling Cr(VI) sorption onto biomass from metal binary mixtures solutions

International Nuclear Information System (INIS)

Liu, Chang; Fiol, Núria; Villaescusa, Isabel; Poch, Jordi

2016-01-01

In the last decades Cr(VI) sorption equilibrium and kinetic studies have been carried out using several types of biomasses. However there are few researchers that consider all the simultaneous processes that take place during Cr(VI) sorption (i.e., sorption/reduction of Cr(VI) and simultaneous formation and binding of reduced Cr(III)) when formulating a model that describes the overall sorption process. On the other hand Cr(VI) scarcely exists alone in wastewaters, it is usually found in mixtures with divalent metals. Therefore, the simultaneous removal of Cr(VI) and divalent metals in binary mixtures and the interactive mechanism governing Cr(VI) elimination have gained more and more attention. In the present work, kinetics of Cr(VI) sorption onto exhausted coffee from Cr(VI)–Cu(II) binary mixtures has been studied in a stirred batch reactor. A model including Cr(VI) sorption and reduction, Cr(III) sorption and the effect of the presence of Cu(II) in these processes has been developed and validated. This study constitutes an important advance in modeling Cr(VI) sorption kinetics especially when chromium sorption is in part based on the sorbent capacity of reducing hexavalent chromium and a metal cation is present in the binary mixture. - Highlights: • A kinetic model including Cr(VI) reduction, Cr(VI) and Cr(III) sorption/desorption • Synergistic effect of Cu(II) on Cr(VI) elimination included in the model • Model validation by checking it against independent sets of data

Cr(VI) retention and transport through Fe(III)-coated natural zeolite

Energy Technology Data Exchange (ETDEWEB)

Du, Gaoxiang [School of Materials Science and Technology, China University of Geosciences, Beijing 100083 (China); Li, Zhaohui, E-mail: li@uwp.edu [School of Materials Science and Technology, China University of Geosciences, Beijing 100083 (China); Geosciences Department, University of Wisconsin-Parkside, Kenosha, WI 53144 (United States); Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China); Liao, Libing [School of Materials Science and Technology, China University of Geosciences, Beijing 100083 (China); Hanson, Renee; Leick, Samantha; Hoeppner, Nicole [Geosciences Department, University of Wisconsin-Parkside, Kenosha, WI 53144 (United States); Jiang, Wei-Teh [Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China)

2012-06-30

Graphical abstract: Breakthrough curves of Cr(VI) from columns packed with raw zeolite (a) and Fe(III)-zeolite (b). The solid line in (b) is the HYDRUS-1D fit to the observed data with adsorption term only, while the dashed line in (b) includes a reduction term in the HYDRUS-1D fit. Highlights: Black-Right-Pointing-Pointer Zeolite modified with Fe(III) could be used for adsorption and retention of Cr(VI). Black-Right-Pointing-Pointer The Fe present on zeolite was in an amorphous Fe(OH){sub 3} form. Black-Right-Pointing-Pointer A Cr(VI) adsorption capacity of 82 mg/kg was found on Fe(III)-zeolite. Black-Right-Pointing-Pointer A Cr(VI) retardation factor of 3 or 5 was determined from column and batch studies. - Abstract: Cr(VI) is a group A chemical based on the weight of evidence of carcinogenicity. Its transport and retention in soils and groundwater have been studied extensively. Zeolite is a major component in deposits originated from volcanic ash and tuff after alteration. In this study, zeolite aggregates with the particle size of 1.4-2.4 mm were preloaded with Fe(III). The influence of present Fe(III) on Cr(VI) retention by and transport through zeolite was studied under batch and column experiments. The added Fe(III) resulted in an enhanced Cr(VI) retention by the zeolite with a capacity of 82 mg/kg. The Cr(VI) adsorption on Fe(III)-zeolite followed a pseudo-second order kinetically and the Freundlich adsorption isotherm thermodynamically. Fitting the column experimental data to HYDRUS-1D resulted in a retardation factor of 3 in comparison to 5 calculated from batch tests at an initial Cr(VI) concentration of 3 mg/L. The results from this study showed that enhanced adsorption and retention of Cr(VI) may happen in soils derived from volcanic ash and tuff that contains significant amounts of zeolite with extensive Fe(III) coating.

Simultaneous Treatment of Agro-Industrial and Industrial Wastewaters: Case Studies of Cr(VI/Second Cheese Whey and Cr(VI/Winery Effluents

Directory of Open Access Journals (Sweden)

Triantafyllos I. Tatoulis

2018-03-01

Full Text Available Hexavalent chromium (Cr(VI was co-treated either with second cheese whey (SCW or winery effluents (WE using pilot-scale biological trickling filters in series under different operating conditions. Two pilot-scale filters in series using plastic support media were used in each case. The first filter (i.e., Cr-SCW-filter or Cr-WE-filter aimed at Cr(VI reduction and the partial removal of dissolved chemical oxygen demand (d-COD from SCW or WE and was inoculated with indigenous microorganisms originating from industrial sludge. The second filter in series (i.e., SCW-filter or WE-filter aimed at further d-COD removal and was inoculated with indigenous microorganisms that were isolated from SCW or WE. Various Cr(VI (5–100 mg L−1 and SCW or WE (d-COD, 1000–25,000 mg L−1 feed concentrations were tested. Based on the experimental results, the sequencing batch reactor operating mode with recirculation of 0.5 L min−1 proved very efficient since it led to complete Cr(VI reduction in the first filter in series and achieved high Cr(VI reduction rates (up to 36 and 43 mg L−1 d−1, for SCW and WW, respectively. Percentage d-COD removal for SCW and WE in the first filter was rather low, ranging from 14 to 42.5% and from 4 to 29% in the Cr-SCW-filter and Cr-WE-filter, respectively. However, the addition of the second filter in series enhanced total d-COD removal to above 97% and 90.5% for SCW and WE, respectively. The above results indicate that agro-industrial wastewater could be used as a carbon source for Cr(VI reduction, while the use of two trickling filters in series could effectively treat both industrial and agro-industrial wastewaters with very low installation and operational costs.

Ternary uranium(VI) carbonato humate complex studied by cryo-TRLFS

Energy Technology Data Exchange (ETDEWEB)

Steudtner, R.; Sachs, S.; Schmeide, K.; Brendler, V.; Bernhard, G. [Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany). Inst. of Radiochemistry

2011-07-01

The complex formation of U(VI) with humic acid (HA) in the presence of carbonate was studied by time-resolved laser-induced fluorescence spectroscopy at low temperature (cryo-TRLFS) at pH 8.5. In the presence of HA, a decrease of the luminescence intensity of U(VI) and no shift of the emission band maxima in comparison to the luminescence spectrum of the UO{sub 2}(CO{sub 3}){sub 3}{sup 4-} complex, the dominating U(VI) species under the applied experimental conditions in the absence of HA, was observed. The formation of a ternary U(VI) carbonato humate complex of the type UO{sub 2}(CO{sub 3}){sub 2}HA(II){sup 4-} starting from UO{sub 2}(CO{sub 3}){sub 3}{sup 4-} was concluded from the luminescence data. For this complex a complex stability constant of log K=2.83 {+-} 0.17 was determined. Slope analysis resulted in a slope of 1.12 {+-} 0.11, which verifies the postulated complexation reaction. The results agree very well with literature data. Speciation calculations show that the formation of the ternary U(VI) carbonato humate complex can significantly influence the U(VI) speciation under environmental conditions. (orig.)

Recovery of uranium (VI) from low level aqueous radioactive waste

International Nuclear Information System (INIS)

Kulshrestha, Mukul

1996-01-01

Investigation was undertaken to evaluate the uranium (VI) removal and recovery potential of a naturally occurring, nonviable macrofungus, Ganoderma Lucidum from the simulated low level aqueous nuclear waste. These low level waste waters discharged from nuclear mine tailings and nuclear power reactors have a typical U(VI) concentration of 10-100 mg/L. It is possible to recover this uranium economically with the advent of biosorption as a viable technology. Extensive laboratory studies have revealed Ganoderma Lucidum to be a potential biosorbent with a specific uptake of 2.75 mg/g at an equilibrium U(VI) concentration of 10 mg/L at pH 4.5. To recover the sorbed U(VI), the studies indicated 0.2N Na 2 CO 3 to be an effective elutant. The kinetics of U(VI) desorption from loaded Ganoderma Lucidum with 0.2N Na 2 CO 3 as elutant, was found to be rapid with more than 75% recovery occurring in the first five minutes, the specific metal release rate being 0.102 mg/g/min. The equilibrium data fitted to a linearised Freundlich plot and exhibited a near 100% recovery of sorbed U(VI), clearly revealing a cost-effective method of recovery of precious uranium from low level wastewater. (author). 7 refs., 3 figs., 1 tab

Solvent impregnated resin for isolation of U(VI) from industrial wastes

International Nuclear Information System (INIS)

Karve, M.; Rajgor, R.V.

2008-01-01

A solid-phase extraction method based upon impregnation of Cyanex 302 (bis(2,4,4- trimethylpentyl)mono-thio-phosphinic acid) on Amberlite XAD-2 resin is proposed for isolation of U(VI) from uranmicrolite ore tailing samples and industrial effluent samples. U(VI) was sorbed from nitric acid media on the solvent-impregnated resin (SIR) and was recovered completely with 1.0 M HCl. Based upon sorption behavior of U(VI) with Cyanex 302, it was quantitatively sorbed on the SIR in a dynamic method, while the other metal ions were not sorbed by the modified resin. The preparation of impregnated resin is simple, based upon physical interaction of the extractant and solid support, has good sorption capacity for U(VI), and is also reliable for detection of traces of U(VI). (authors)

Cr (VI) remediation by indigenous bacteria in soils contaminated by chromium-containing slag

International Nuclear Information System (INIS)

Chai Liyuan; Huang Shunhong; Yang Zhihui; Peng Bing; Huang Yan; Chen Yuehui

2009-01-01

Hexavalent chromium (Cr) is a toxic element causing serious environmental threat. Recently, more and more attention is paid to the bio-remediation of Cr (VI) in the contaminated soils. Cr (VI) remediation by indigenous bacteria in soils contaminated by chromium-containing slag at a steel-alloy factory in Hunan Province, China, was investigated in the present study. The results showed that when sufficient nutrients were amended into the contaminated soils, total Cr (VI) concentration declined from the initial value of 462.8 to 10 mg kg -1 at 10 days and the removal rate was 97.8%. Water soluble Cr (VI) decreased from the initial concentration of 383.8 to 1.7 mg kg -1 . Exchangeable Cr (VI) and carbonates-bound Cr (VI) were removed by 92.6% and 82.4%, respectively. Meanwhile, four Cr (VI) resistant bacterial strains were isolated from the soil under the chromium-containing slag. Only one strain showed a high ability for Cr (VI) reduction in liquid culture. This strain was identified as Pannonibacter phragmitetus sp. by gene sequencing of 16S rRNA. X-ray photoelectron spectroscope (XPS) analysis indicated that Cr (VI) was reduced into trivalent chromium. The results suggest that indigenous bacterial strains have potential application for Cr (VI) remediation in the soils contaminated by chromium-containing slag.

Impact of water quality parameters on the sorption of U(VI) onto hematite

International Nuclear Information System (INIS)

Zhao Donglin; Wang Xianbiao; Yang Shitong; Guo Zhiqiang; Sheng Guodong

2012-01-01

In this study, the sorption of U(VI) from aqueous solution on hematite was studied as a function of various water quality parameters such as contact time, pH, ionic strength, soil humic acid (HA) or fulvic acid (FA), solid content and temperature by using a batch technique. The results demonstrated that the sorption of U(VI) was strongly dependent on ionic strength at pH 6.0 and the sorption was mainly dominated by inner-sphere surface complexation. The presence of HA/FA increases U(VI) sorption at low pH, whereas decreases U(VI) sorption at high pH. The thermodynamic parameters (ΔH 0 , ΔS 0 , and ΔG 0 ) were calculated from the temperature dependent sorption isotherms, and the results suggested that U(VI) sorption was a spontaneous and endothermic process. The results might be important for the application of hematite in U(VI) pollution management. Highlights: ► The sorption of U(VI) was strongly dependent on ionic strength at pH 6.0. ► A positive effect of HA/FA on U(VI) sorption was found at low pH, whereas a negative effect was observed at high pH. ► U(VI) sorption was a spontaneous and endothermic process. ► The results are quite important for the application of hematite in U(VI) pollution management.

Electrochemical processes for the environmental remediation of toxic Cr(VI): A review

International Nuclear Information System (INIS)

Jin, Wei; Du, Hao; Zheng, Shili; Zhang, Yi

2016-01-01

Highlights: • Recent advances in electrochemical technologies for practical Cr(VI) treatment applications was reviewed. • The mechanism and performance of electrocoagulation, electrochemical reduction, electrodialysis, electro-electrodialysis and electrodeionization were discussed and compared. • The remained challenges and future perspectives were commented. - Abstract: Hexavalent chromium Cr(VI) is extremely toxic and classified as one of the 17 chemicals posing the greatest threat to humans. Large amounts of Cr(VI) compounds are directly or indirectly discharged into the environment, therefore considerable efforts have been made to control the Cr(VI) concentration below the recommended level. It has been demonstrated that electrochemical technique is one of the most efficient and environmental benign approach for the Cr(VI) removal. This review aims at recent advances in electrochemical technology for practical Cr(VI) treatment applications. By using the “clean reagent” of electron, Cr(VI) can be completely eliminated or separated via different electrochemical techniques such as electrocoagulation, electrochemical reduction, electrodialysis, electro-electrodialysis and electrodeionization. Besides, the mechanism and performance of different strategies are commented and compared. The treatment process is largely dependent on variables such as pH, electrode materials, cell configuration and techniques integration. Furthermore, the remained limitation and challenges for the electrochemical Cr(VI) remediation are also discussed.

Proceeding of the Scientific Meeting and Presentation on Basic Research of Nuclear Science and Technology: Book II. Nuclear Chemistry, Process Technology, and Radioactive Waste Processing and Environment; Pertemuan dan Presentasi Ilmiah Penelitian Dasar Ilmu Pengetahuan dan Teknologi Nuklir. Buku II. Kimia Nuklir, Teknologi Proses, dan Pengolahan Limbah Radioaktif dan Lingkungan

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-06-01

The proceeding contains papers presented on Scientific Meeting and Presentation on on Basic Research of Nuclear Science and Technology, held in Yogyakarta, 25-27 April 1995. This proceeding is second part of two books published for the meeting contains papers on nuclear chemistry, process technology, and radioactive waste management and environment. There are 62 papers indexed individually. (ID)

Bulk solubility and speciation of plutonium(VI) in phosphate-containing solutions

International Nuclear Information System (INIS)

Weger, H.T.; Okajima, S.; Cunnane, J.C.; Reed, D.T.

1992-01-01

The solubility and speciation of Pu(VI) with phosphate as a function of pH was investigated to determine the ability of phosphate to act as an actinide getter. The general properties were first investigated and are reported here with the goal of performing more quantitative experiments in the future. Solubility was approached from oversaturation at initial pH = 4, 10 and 13.4. Absorption spectra were recorded, the solution filtered and the filtrate counted. Absorption spectra were obtained at varying phosphate concentrations and at pH of 2.7 to 11.9. The effect of complexation on the 833 mn Pu(VI) band was characterized. Evidence for three phosphate complexes was obtained for pH -5 to 10 -6 M Pu(VI) was measured in the filtrate at pH ≤ 10 that were passed through a 50 mn filter. Pu(VI) complexes with phosphate over hydroxide at pH ≤ 11.6, but at pH ≥ 11.9, only hydrolyzed Pu(VI) was detected. At pH = 12, the concentration of Pu(VI) was as high as 10 -4 M

Bacillus lichenformis γ-glutamyl exopolymer: Physicochemical characterization and U(VI) interaction

International Nuclear Information System (INIS)

He, L.M.; Neu, M.P.; Vanderberg, L.A.

2000-01-01

Complexation by microbially produced exopolymers may significantly impact the environmental mobility and toxicity of metals. This study focused on the conformational structure of the bacterial exopolymer, γ-D-poly(glutamic acid) and its interactions with U(VI) examined using ATR-FTIR spectroscopy. Solution pH, polymer concentration, and ionic strength affected the conformation of the exopolymer, and U(VI) binding was monitored. At low pH, low concentration, or low ionic strength, this exopolymer exists in an α-helical conformation, while at high pH, concentration, or ionic strength the exopolymer exhibits a β-sheet structure. The change in exopolymer conformation is likely to influence the number and nature of exposed surface functional groups, sites most responsible for metal complexation. The authors found the polyglutamate capsule binds U(VI) in a binuclear, bidentate fashion; in contrast the glutamate monomer forms a mononuclear, bidentate complex with U(VI). The apparent polynuclear binding of U(VI) may induce β-sheet structure formation provided the U(VI) Concentration is sufficiently high

Selectivity enhancement of phosphate based functional polymeric gels towards Uranium(VI) using ion imprinting

International Nuclear Information System (INIS)

Chappa, Sankararao; Agarwal, Chhavi; Pandey, A.K.

2015-01-01

The imprinting of gel containing polymer chains of ethylene glycol methacrylate phosphate (EGMP) for U(VI) ions were carried out. The U(VI) imprinting has been carried out in pure EGMP and in EGMP: poly(ethylene glycol) methacrylate (PEGMA) = 1:9 composition. Complexation of the monomer with template (U(VI)) followed by polymerization have been used to imprint the U(VI) onto the polymer chains. The comparison of uptake studies of U(VI) and Pu(IV) at 3 M HNO 3 shows increased selectivity of U(VI) relative to Pu(IV) for both the gel compositions. The less uptake of U(VI) for imprinted EGMP:PEGMA gel relative to pure imprinted EGMP gel at tracer level can be possibly due to the requirement of two EGMP units in the vicinity for U(VI) complexation. (author)

Clinical evaluation of complete solo surgery with the "ViKY®" robotic laparoscope manipulator.

Science.gov (United States)

Takahashi, Masahiro; Takahashi, Masanori; Nishinari, Naoto; Matsuya, Hideki; Tosha, Tsutomu; Minagawa, Yukihiro; Shimooki, Osamu; Abe, Tadashi

2017-02-01

Advancement in both surgical technique and medical equipment has enabled solo surgery. ViKY ® Endoscope Positioning System (ViKY ® ) is a robotic system that remotely controls an endoscope and provides direct vision control to the surgeon. Here, we report our experience with ViKY ® -assisted solo surgery. We retrospectively examined 25 cases of solo surgery TAPP with ViKY ® . ViKY ® was setup by the surgeon alone, and the setup duration was determined as the time at which the side rail was positioned and that when the endoscope was installed. For assessing the control unit, the number of false movements was counted. We compared the operative results between ViKY ® -assisted solo surgery TAPP and the conventional method with an assistant. The average time to set up ViKY ® was 7.9 min. The average number of commands for ViKY ® during surgery was 98.3, and the average number of errors and no response of control unit was 7.9. The mean duration of surgery was 136 min for the ViKY ® group, including the setup time, and 117 min for the conventional method. No case required an assistant during the operation. There was also no difference between the two groups with regard to postoperative complications and the rate of recurrence. ViKY ® proved reliable in recognizing orders with very few failures, and the operations were performed safely and were comparable to the conventional operations with assistants. Solo surgery with ViKY ® was beneficial in this clinical evaluation.

cis-dioxomolybdenum(VI)-(ONO)

Indian Academy of Sciences (India)

Various ONO type Schiff base ligands L(H)2 used for the preparation of ... and derivatives.6–33 Depending on the method of prepa- ration .... HCl. Scheme 6. Synthesis of a Mo(VI) Schiff base complexe by selective inversion at C–1 carbon of a ...

Multi-crystalline II-VI based multijunction solar cells and modules

Science.gov (United States)

Hardin, Brian E.; Connor, Stephen T.; Groves, James R.; Peters, Craig H.

2015-06-30

Multi-crystalline group II-VI solar cells and methods for fabrication of same are disclosed herein. A multi-crystalline group II-VI solar cell includes a first photovoltaic sub-cell comprising silicon, a tunnel junction, and a multi-crystalline second photovoltaic sub-cell. A plurality of the multi-crystalline group II-VI solar cells can be interconnected to form low cost, high throughput flat panel, low light concentration, and/or medium light concentration photovoltaic modules or devices.

Analisis Redaman Pada Jaringan FTTH (Fiber To The Home Dengan Teknologi GPON (Gigabit Passive Optical Network Di PT MNC Kabel Mediacom

Directory of Open Access Journals (Sweden)

Minal Abral

2017-06-01

Full Text Available iber optic merupakan teknologi yang menyediakan kapasitas bandwith besar dengan kecepatan tinggi, tidak dipengaruhi interferensi gelombang elektromagnetik, Sejalan dengan berkembang secara pesatnya penggunaan serat optik sebagai medium penghantar, ada kemungkinan terjadinya hilang informasi akibat kerugian dari pemanjangan kabel fiber optic ataupun penyambungan kabel fiber optic, kerugian tersebut yaitu redaman. Dalam penerapan metode link power budget, perhitungan redaman dilakukan dengan data yang diperoleh berdasarkan standarisasi dan pengukuran menggunakan perangkat optical power meter. Hasil analisa perhitungan, sistem mampu dalam keadaan normal menggunakan layanan gigabit passive optical network dapat diterima oleh perangkat akhir jaringan fiber to the home pada pelanggan perusahaan PT MNC Kabel Mediacom yang berada di Kelurahan Jati RW 02 Pulo Gadung Jakarta Timur.

24 CFR 972.115 - Relationship between required conversions and HOPE VI developments.

Science.gov (United States)

2010-04-01

... conversions and HOPE VI developments. 972.115 Section 972.115 Housing and Urban Development Regulations... Relationship between required conversions and HOPE VI developments. HUD actions to approve or deny proposed HOPE VI revitalization plans must be consistent with the requirements of this subpart. Developments...

Enhanced Cr(VI) removal by polyethylenimine- and phosphorus-codoped hierarchical porous carbons.

Science.gov (United States)

Chen, Shixia; Wang, Jun; Wu, Zeliang; Deng, Qiang; Tu, Wenfeng; Dai, Guiping; Zeng, Zheling; Deng, Shuguang

2018-08-01

The amino- and phosphorus-codoped (N,P-codoped) porous carbons derived from oil-tea shells were facilely fabricated through a combination of phosphoric acid (H 3 PO 4 ) activation and amino (polyethylenimine, PEI) modification method. The as-synthesized carbon adsorbents were systematically characterized and evaluated for Cr(VI) removal in aqueous solutions. The relationship between adsorbent properties and adsorption behaviors was illustrated. Moreover, the influences of contact time, initial Cr(VI) concentration, pH, coexisting anions and temperature were also investigated. The adsorption behavior of Cr(VI) could be perfectly described by the pseudo-second-order kinetic model and Sips adsorption model. The maximum adsorption capacity of Cr(VI) on the carbon adsorbents synthesized in this work was 355.0 mg/g, and this excellent Cr(VI) capacity could be sustained with other coexisting anions. In addition to high surface area and suitable pore size distribution, the high Cr(VI) removal capacity is induced by rich heteroatoms incorporation and the Cr(VI) removal mechanism was clearly illustrated. Furthermore, the continuous column breakthrough experiment on obtained N,P-codoped carbon was conducted and well fitted by the Thomas model. This work revealed that PEI modification and P-containing groups could significantly enhance Cr(VI) adsorption capacity and make these N,P-codoped biomass-derived carbons potent adsorbents in practical water treatment applications. Copyright © 2018 Elsevier Inc. All rights reserved.

Manajemen Sumber Daya Teknologi Informasi Laboratorium Komputer Menggunakan Balanced Scorecard (BSC dan COBIT 5

Directory of Open Access Journals (Sweden)

M. Panji Ismail

2017-05-01

Full Text Available Laboratorium komputer merupakan salah satu sarana pembelajaran yang berbasis Teknologi Informasi (TI yang terdiri dari tiga sumber daya TI, yaitu software, hardware, dan brainware. Tidak adanya kesesuaian antara kemampuan hardware dengan spesifikasi hardware yang digunakan dapat menghambat pengguna (brainware dalam melakukan praktikum dan pembelajaran di laboratorium. Selain itu, ketidaksesuaian tersebut juga mengakibatkan software berjalan lambat dan computer sering error sehingga praktikum menjadi terganggu dan berjalan tidak lancar. Untuk mengetahui kesesuaian antar sumber daya TI yang ada di laboratorium dibutuhkan proses pengukuran manajemen sumber daya TI yang ada saat ini. Skala likert menjadi salah satu metode untuk mengukur kinerja software, hardware, dan tata kelola laboratorium saat ini. Hasil pengukuran kemudian dievaluasi menggunakan framework Balance Scorecard (BSC dengan melalui beberapa tahapan dan penyelarasan strategi TI. Setelah mengetahui hasil evaluasi dan kendala-kendala apa saka yang ada dalam melakukan pengelolaan maka langkah berikutnya adalah menentukan bagaimana cara memperbaiki dan melakukan peningkatan tata kelola TI. COBIT 5 akan menjadi framework pelengkap untuk memperbaiki sekaligus memprediksi pengembangan manajemen sumber daya TI. Hasil penelitian ini menunjukkan bahwa integrase antara COBIT 5 dengan Balance Scorecard (BSC memberikan kemampuan dalam melakukan pengukuran tata kelola laboratorium serta memberikan kemampuan untuk meningkatkan pelayanan secara kontinyu.

Introduktion

DEFF Research Database (Denmark)

Evald, Jens

2007-01-01

Interfacet mellem menneske og maskine spreder sig. Der bliver flere og flere interfaces – de bliver mobile, forbundne, billigere og indlejrede i dagligdags genstande, men er også stadig skærm- og tastaturbaserede. Vi lever i en interfacekultur, hvor stadig mere arbejde udføres via interfaces, hvor...... flere og flere af de ting, vi omgiver os med, forsynes med processorkraft og interfaces, og hvor vi også i stigende grad opsøger og oplever kunst, kultur og underholdning via interfaces for eksempel på nettet, via computere, spilkonsoller eller mobiltelefoner. Bogen her beskæftiger sig med grænsefladen...... mellem menneske og maskine, kultur og data: Hvordan udfordrer interfacet vores kunst og kultur, og hvordan forholder det sig til æstetikkens teorier og traditioner? Der findes adskillige bøger om interfacets design og teknologi, oftest er de rettet mod interfaces til arbejdsbrug, men gennem de seneste år...

TRANSFEKSI MERUPAKAN METODE TEKNOLOGI TRANSGENIK PENYISIPAN GREEN FLOURESCENT PROTEIN TERHADAP IKAN WILD BETTA

Directory of Open Access Journals (Sweden)

Eni Kusrini

2015-06-01

Full Text Available Teknik transfer gen banyak dikembangkan untuk mengintroduksi molekul DNA ke dalam embrio. Keberhasilan transfer gen menggunakan metode transfeksi ditentukan oleh berbagai faktor, antara lain pemilihan larutan transfeksi yang sesuai dengan mempertimbangkan kesediaan secara komersial, mudah diaplikasikan, keberhasilan tinggi, dan tidak bersifat toksik terhadap embrio. Studi awal untuk mengetahui keberhasilan transfer gen terhadap embrio ikan wild betta digunakan Green Fluorescent Protein (GFP dan juga dapat digunakan sebagai model terhadap ikan betta. GFP merupakan gen yang mengkodekan protein dan memiliki sifat berpendar hijau. Induk jantan dan betina dipijahkan dengan perbandingan 1:1 pada wadah baskom dengan ketinggian air ± 14 cm serta diberikan substrat. Transfeksi dilakukan pada embrio fase pembelahan 2 sel. Larutan transfeksi dibuat dari campuran DNA plasmid pada media NaCl 0.9% hingga mencapai konsentrasi akhir 100 μL media (campuran transfast + DNA + NaCl. Aktivitas gen ini dapat divisualisasikan dengan menggunakan sinar ultra violet. Keberhasilan dari teknik transfer gen tersebut dibuktikan dengan adanya ekspresi gen atau deteksi DNA gen GFP yang dimasukkan. Ekspresi hasil korporasi DNA ke dalam telur melalui transfeksi pada wild betta dan keberhasilan transfer gen GFP dapat dibuktikan dengan analisis PCR. Tujuan dari penulisan makalah ini adalah menguraikan tentang metode transfeksi yang efektif untuk teknologi transfer gen terhadap ikan wild betta.

A combined wet chemistry and EXAFS study of U(VI) uptake by cementitious materials

International Nuclear Information System (INIS)

Wieland, E.; Harfouche, M.; Tits, J.; Kunz, D.; Daehn, R.; Fujita, T.; Tsukamoto, M.

2006-01-01

The sorption behaviour and speciation of U(VI) in cementitious systems was investigated by a combination of wet chemistry experiments and synchrotron-based X-ray absorption spectroscopy (XAS) measurements. Radiotracer studies using 233 U were carried out on hardened cement paste (HCP) and calcium silicate hydrates (C-S-H), which are the major constituents of HCP, to determine the uptake kinetics and sorption isotherms. C-S-H phases were synthesized using different methods for solid phase preparation, which enabled us to study the U(VI) uptake by different types of C-S-H phases and a wide range of Ca/Si compositions, and to distinguish U(VI) sorption on the surface of C-S-H from U(VI) incorporation into the structure. XAS measurements were performed using U(VI) loaded HCP and C-S-H materials (sorption and co-precipitation samples) to gain structural information on the U(VI) speciation in these systems, i.e., the type and number of neighbouring atoms, and bond distances. Examples of studies that have utilized XAS to characterize U(VI) speciation in cementitious systems are still rare, and to the best of our knowledge, detailed XAS investigations of the U(VI)/C-S-H system are lacking. The results obtained from the combined use of wet chemical and spectroscopic techniques allow mechanistic models of the immobilization process to be proposed for cementitious waste forms containing low and high U(VI) inventories. In the latter case U(VI) immobilization is controlled by a solubility-limiting process with the U(VI) mineral predominantly formed under the conditions prevailing in cementitious systems. At low U(VI) concentrations, however, U(VI) appears to be predominantly bound onto C-S-H phases. The coordination environment of U(VI) taken up by C-S-H was found to resemble that of U(VI) in uranophane. A mechanistic understanding of the U(VI) binding by cementitious materials will allow more detailed and scientifically well founded predictions of the retention of

Contribution of extracellular polymeric substances from Shewanella sp. HRCR-1 biofilms to U(VI) immobilization.

Science.gov (United States)

Cao, Bin; Ahmed, Bulbul; Kennedy, David W; Wang, Zheming; Shi, Liang; Marshall, Matthew J; Fredrickson, Jim K; Isern, Nancy G; Majors, Paul D; Beyenal, Haluk

2011-07-01

The goal of this study was to quantify the contribution of extracellular polymeric substances (EPS) to U(VI) immobilization by Shewanella sp. HRCR-1. Through comparison of U(VI) immobilization using cells with bound EPS (bEPS) and cells with minimal EPS, we show that (i) bEPS from Shewanella sp. HRCR-1 biofilms contribute significantly to U(VI) immobilization, especially at low initial U(VI) concentrations, through both sorption and reduction; (ii) bEPS can be considered a functional extension of the cells for U(VI) immobilization and they likely play more important roles at lower initial U(VI) concentrations; and (iii) the U(VI) reduction efficiency is dependent upon the initial U(VI) concentration and decreases at lower concentrations. To quantify the relative contributions of sorption and reduction to U(VI) immobilization by EPS fractions, we isolated loosely associated EPS (laEPS) and bEPS from Shewanella sp. HRCR-1 biofilms grown in a hollow fiber membrane biofilm reactor and tested their reactivity with U(VI). We found that, when reduced, the isolated cell-free EPS fractions could reduce U(VI). Polysaccharides in the EPS likely contributed to U(VI) sorption and dominated the reactivity of laEPS, while redox active components (e.g., outer membrane c-type cytochromes), especially in bEPS, possibly facilitated U(VI) reduction.

Sorption of chromium (VI) by Mg/Fe hydrotalcite type compunds

Energy Technology Data Exchange (ETDEWEB)

García-Sosa, I., E-mail: irma.garcia@inin.gob.mx; Cabral-Prieto, A., E-mail: agustin.cabral@inin.gob.mx [Instituto Nacional de Investigaciones Nucleares, Departamento de Química (Mexico); Nava, N., E-mail: tnava@imp.mx; Navarrete, J. [Instituto Mexicano del Petróleo (Mexico); Olguín, M. T., E-mail: teresa.olguin@inin.gob.mx [Instituto Nacional de Investigaciones Nucleares, Departamento de Química (Mexico); Escobar, Luis, E-mail: luis.escobar@inin.gob.mx [Instituto Nacional de Investigaciones Nucleares, Departamento de Física (Mexico); López-Castañares, R., E-mail: rlc@anuies.mx; Olea-Cardoso, O., E-mail: olc@anuies.mx [Universidad Autónoma del Edo. de México, Facultad de Química (Mexico)

2015-06-15

The synthesis by co-precipitation and characterization by X-ray diffraction, Raman and Mössbauer spectroscopies of Mg-Fe-hydrotalcite compounds, and their sorption capacities for Cr(VI) in aqueous media were carried out. The average sorption capacity of Cr(VI) for the non-thermal treated samples was of 6.2 mg/g. The ferrihydrite was omnipresent in all prepared hydrotalcite samples. A brief discussion is made on the role of both the hydrotalcite and ferrihydrite for removing such amount of Cr(VI)

Uranium(VI) retention on quartz and kaolinite. Experiments and modelling

International Nuclear Information System (INIS)

Mignot, G.

2001-01-01

The behaviour of uranium in the geosphere is an important issue for safety performance assessment of nuclear waste repositories, or in the context of contaminated sites due to mining activity related to nuclear field. Under aerobic conditions, the fate of uranium is mainly governed by the ability of minerals to sorb U(VI) aqueous species. Hence, a thorough understanding of U(VI) sorption processes on minerals is required to provide a valuable prediction of U(VI) migration in the environment. In this study, we performed sorption/desorption experiments of U(VI) on quartz and kaolinite, for systems favouring the formation in solution (i) of UO 2 2+ and monomeric hydrolysis products or (ii) of di-/tri-meric uranyl aqueous species, and / or U(VI)-colloids or UO 2 (OH) 2 precipitates, or (iii) of uranyl-carbonate complexes. Particular attention was paid to determine the surface characteristics of the solids and their modification due to dissolution/precipitation processes during experiments. A double layer surface complexation model was applied to our experimental data in order to derive surface complexation equilibria and intrinsic constants which allow a valuable description of U(VI) retention over a wide range of pH, ionic strength, initial concentration of uranium [0.1-10μM] and solid - solution equilibration time. U(VI) sorption on quartz was successfully modeled by using two sets of adsorption equilibria, assuming (i) the formation of the surface complexes SiOUO 2 + , SiOUO 2 OH and SiO(UO 2 ) 3 (OH) 5 , or (ii) the formation of the mono-dentate complex SiO(UO 2 ) 3 (OH) 5 and of the bidentate complex (SiO) 2 UO 2 . Assumptions on the density of each type of surface sites of kaolinite and on their acid-base properties were made from potentiometric titrations of kaolinite suspensions. We proposed on such a basis a set of surface complexation equilibria which accounts for U(VI) uptake on kaolinite over a wide range of chemical conditions, with aluminol edge sites as

strong>Hvad skal vi med en hjerne?strong>

DEFF Research Database (Denmark)

Hermansen, Judy

2009-01-01

neurologen Antonio Damasio, at sikre vores overlevelse og velbefindende (i nævnte rækkefølge). Vi ved, at der findes såkaldte belønningsstrukturer i hjernen på både dyr og mennesker, som aktiverer følelser af velbehag, når vi gør "det rigtige", dvs. noget der er godt for os. Men hvordan de mere konkret...

Reduction of Cr(VI) in aqueous solution with DC diaphragm glow discharge

International Nuclear Information System (INIS)

Wang, Xiaoyan; Jin, Xinglong; Zhou, Minghua; Chen, Zhenhai; Deng, Kai

2013-01-01

This paper investigated the reduction of Cr(VI) in aqueous solution with direct current diaphragm glow discharge (DGD). The glow discharge sustained around the hole on a quartz tube which divided the electrolyte cell into two parts. The reduction efficiencies of Cr(VI) under different applied voltages, initial conductivities, hole diameters, hole numbers, initial pH values and initial concentrations were systematically studied. The results showed that the reduction efficiency of Cr(VI) increased with the increase of applied voltage, initial conductivity, hole diameter and hole number. The different initial pH values showed less effects on the reduction of Cr(VI). The reduction efficiency decreased with the increasing initial concentration. In addition, the simultaneous reduction of Cr(VI) and decolorization of acid orange (AO) with DGD were also fulfilled. Furthermore, the energy efficiency for Cr(VI) reduction with DGD was calculated and compared with those in photocatalysis and other glow discharge reactor

Characterization of U(VI)-carbonato ternary complexes on hematite: EXAFS and electrophoretic mobility measurements

Science.gov (United States)

Bargar, John R.; Reitmeyer, Rebecca; Lenhart, John J.; Davis, James A.

2000-01-01

We have measured U(VI) adsorption on hematite using EXAFS spectroscopy and electrophoresis under conditions relevant to surface waters and aquifers (0.01 to 10 μM dissolved uranium concentrations, in equilibrium with air, pH 4.5 to 8.5). Both techniques suggest the existence of anionic U(VI)-carbonato ternary complexes. Fits to EXAFS spectra indicate that U(VI) is simultaneously coordinated to surface FeO6 octahedra and carbonate (or bicarbonate) ligands in bidentate fashions, leading to the conclusion that the ternary complexes have an inner-sphere metal bridging (hematite-U(VI)-carbonato) structure. Greater than or equal to 50% of adsorbed U(VI) was comprised of monomeric hematite-U(VI)-carbonato ternary complexes, even at pH 4.5. Multimeric U(VI) species were observed at pH ≥ 6.5 and aqueous U(VI) concentrations approximately an order of magnitude more dilute than the solubility of crystalline β-UO2(OH)2. Based on structural constraints, these complexes were interpreted as dimeric hematite-U(VI)-carbonato ternary complexes. These results suggest that Fe-oxide-U(VI)-carbonato complexes are likely to be important transport-limiting species in oxic aquifers throughout a wide range of pH values.

Extraction kinetics of uranium (VI) with polyurethane foam

International Nuclear Information System (INIS)

Huang, Ting-Chia; Chen, Dong-Hwang; Huang, Shius-Dong; Huang, Ching-Tsven; Shieh, Mu-Chang.

1993-01-01

The extraction kinetics of uranium(VI) from aqueous nitrate solution with polyether-based polyurethane foam was investigated in a batch reactor with automatic squeezing. The extraction curves of uranium(VI) concentration in solution vs. extraction time exhibited a rather rapid exponential decay within the first few minutes, followed by a slower exponential decay during the remaining period. This phenomenon can be attributed to the presence of two-phase structure, hard segment domains and soft segment matrix in the polyurethane foam. A two-stage rate model expressed by a superposition of two exponential curves was proposed, according to which the experimental data were fitted by an optimization method. The extraction rate of uranium (VI) was also found to increase with increasing temperature, nitrate concentration, and hydration of the cation of nitrate salt. (author)

Adsorption of Cr(VI and Speciation of Cr(VI and Cr(III in Aqueous Solutions Using Chemically Modified Chitosan

Directory of Open Access Journals (Sweden)

ChunYuan Tao

2012-05-01

Full Text Available A new type of grafting chitosan (CTS was synthesized using 2-hydroxyethyl- trimethyl ammonium chloride (HGCTS. The adsorption of Cr(VI on HGCTS was studied. The effect factors on adsorption and the adsorption mechanism were considered. The results indicated that the HGCTS could concentrate and separate Cr(VI at pH 4.0; the adsorption equilibrium time was 80 min; the maximum adsorption capacity was 205 mg/g. The adsorption isotherm and kinetics were investigated, equilibrium data agreed very well with the Langmuir model and the pseudo second-order model could describe the adsorption process better than the pseudo first-order model. A novel method for speciation of Cr(VI and Cr(III in environmental water samples has been developed using HGCTS as adsorbent and FAAS as determination means. The detection limit of this method was 20 ng/L, the relatively standard deviation was 1.2% and the recovery was 99%~105%.

Wavelengths and energy levels of I V and I VI

International Nuclear Information System (INIS)

Kaufman, V.; Sugar, J.; Joshi, Y.N.

1988-01-01

The spectra of iodine were photographed in the 139--1500-Aat;O region on various spectrographs. Earlier analyses of I V and I VI were revised and extended. For I V 26 lines were classified, and for I VI 35 lines were classified. Ionization energies have been estimated to be 415 510 atm≅ 300 cm -1 (51.52 atm≅ 0.04 eV) and 599 800 atm≅ 3 000 cm -1 (74.37 atm≅ 0.37 eV) for I V and I VI, respectively

Group ib organometallic chemistry. XXXIV. Thermal behaviour and chemical reactivity of tetranuclear Me2N-substituted diarypropenylcopper-copper anion (Vi2Cu4X2) and mixed diarylpropenyl/organocopper (Vi2Cu4R2) compounds

NARCIS (Netherlands)

Hoedt, R.W.M. ten; Koten, G. van; Noltes, J.G.

1980-01-01

Thermal decomposition of configurationally pure 1,2-diarylpropenylcopper compounds Z-Vi2CU4Br2 and Z-Vi2Cu4R2 [Vi = (2-Me2NC6H4)C=C(Me)-(C6H4Me-4), R = 2-Me2NC6H4 or 4-MeC6H4CC] predominantly results in the formation of ViH. In contrast, only dimers (ViVi) were formed on thermolysis of (Z-ViCu2OTf)η

Intervening O vi Quasar Absorption Systems at Low Redshift: A Significant Baryon Reservoir.

Science.gov (United States)

Tripp; Savage; Jenkins

2000-05-01

Far-UV echelle spectroscopy of the radio-quiet QSO H1821+643 (zem=0.297), obtained with the Space Telescope Imaging Spectrograph (STIS) at approximately 7 km s-1 resolution, reveals four definite O vi absorption-line systems and one probable O vi absorber at 0.15quasar in redshift; these are likely intervening systems unrelated to the background QSO. In the case of the strong O vi system at zabs=0.22497, multiple components are detected in Si iii and O vi as well as H i Lyman series lines, and the differing component velocity centroids and b-values firmly establish that this is a multiphase absorption system. A weak O vi absorber is detected at zabs=0.22637, i.e., offset by approximately 340 km s-1 from the zabs=0.22497 system. Lyalpha absorption is detected at zabs=0.22613, but no Lyalpha absorption is significantly detected at 0.22637. Other weak O vi absorbers at zabs=0.24531 and 0.26659 and the probable O vi system at 0.21326 have widely diverse O vi/H i column density ratios with N(O vi)/N(H i) ranging from vi absorbers with rest equivalent width greater than 30 mÅ in the H1821+643 spectrum is remarkably high, dN&solm0;dz approximately 48, which implies with a high (90%) confidence that it is greater than 17 in the low-redshift intergalactic medium. We conservatively estimate that the cosmological mass density of the O vi systems is Omegab(Ovi&parr0; greater, similar0.0008 h-175. With an assumed metallicity of 1/10 solar and a conservative assumption that the fraction of oxygen in the O vi ionization stage is 0.2, we obtain Omegab(Ovi&parr0; greater, similar0.004 h-175. This is comparable to the combined cosmological mass density of stars and cool gas in galaxies and X-ray-emitting gas in galaxy clusters at low redshift.

On halide derivatives of rare-earth metal(III) oxidomolybdates(VI) and -tungstates(VI)

International Nuclear Information System (INIS)

Schleid, Thomas; Hartenbach, Ingo

2016-01-01

Halide derivatives of rare-earth metal(III) oxidomolybdates(VI) have been investigated comprehensively over the last decade comprising the halogens fluorine, chlorine, and bromine. Iodide-containing compounds are so far unknown. The simple composition REXMoO 4 (RE=rare-earth element, X=halogen) is realized for X=F almost throughout the complete lanthanide series as well as for yttrium. While ytterbium and lutetium do not form any fluoride derivative, for lanthanum, only a fluoride-deprived compound with the formula La 3 FMo 4 O 16 is realized. Moreover, molybdenum-rich compounds with the formula REXMo 2 O 7 are also known for yttrium and the smaller lanthanoids. For X=Cl the composition REClMoO 4 is known for yttrium and the whole lanthanide series, although, four different structure types were identified. Almost the same holds for X=Br, however, only two different structure types are realized in this class of compounds. In the case of halide derivatives of rare-earth metal(III) oxidotungstates(VI) the composition REXWO 4 is found for chlorides and bromides only, so far. Due to the similar size of Mo 6+ and W 6+ cations, the structures found for the tungstates are basically the same as for the molybdates. With the larger lanthanides, the representatives for both chloride and bromide derivates exhibit similar structural motifs as seen in the molybdates, however, the crystal structure cannot be determined reliably. In case of the smaller lanthanoids, the chloride derivatives are isostructural with the respective molybdates, although the existence ranges differ slightly. The same is true for rare-earth metal(III) bromide oxidotungstates(VI).

Uranium(VI) Reduction by Nanoscale Zerovalent Iron in Anoxic Batch Systems

International Nuclear Information System (INIS)

Yan, Sen; Hua, Bin; Bao, Zhengyu; Yang, John; Liu, Chongxuan; Deng, Baolin

2010-01-01

This study investigated the influences of pH, bicarbonate, and calcium on U(VI) adsorption and reduction by synthetic nanosize zero valent iron (nano Fe 0 ) particles under an anoxic condition. The results showed that about 87.1%, 82.7% and 78.3% of U(VI) could be reduced within 96 hours in the presence of 10 mM bicarbonate at pHs 6.92, 8.03 and 9.03, respectively. The rates of U(VI) reduction and adsorption by nano Fe 0 , however, varied significantly with increasing pH and concentrations of bicarbonate and/or calcium. Solid phase analysis by X-ray photoelectron spectroscopy confirmed the formation of UO 2 and iron (hydr)oxides as a result of the redox interactions between adsorbed U(VI) and nano Fe 0 . This study highlights the potential important role of groundwater chemical composition in controlling the rates of U(VI) reductive immobilization using nano Fe 0 in subsurface environments.

Extractive behavior of U(VI) in the paraffin soluble ionic liquid

International Nuclear Information System (INIS)

Rama, R.; Kumaresan, R.; Venkatesan, K.A.; Antony, M.P.; Vasudeva Rao, P.R.

2013-01-01

An Aliquat-336 based ionic liquid namely, tri-n-octylmethylammonium bis(2-ethylhexyl)phosphate ((A3636) + (DEHP) - ) was prepared and studied for the extraction of U(VI) from nitric acid medium. Since the ionic liquid, (A336) + (DEHP) - , was miscible in n-dodecane (n-DD), the extraction of U(VI) in the solution of tri-n-butylphosphate (TBP) in n-DD, was investigated in the presence of small concentrations of ionic liquid. The distribution ratio of U(VI) in 0.3 M (A336) + (DEHP) - /n-DD decreased with increase in the concentration of nitric acid. The effect of concentration of TBP, ionic liquid nitric acid and nitrate ion on the extraction of U(VI) in ionic liquid medium was studied. The mechanistic aspect of extraction was investigated by the slope analysis of the extraction data. The studies indicated the feasibility of modifying the extractive properties of U(VI) in TBP/n-DD using ionic liquid. (author)

Gravimetric determination of uranium(VI) and thorium(IV) with substituted pyrazolones

International Nuclear Information System (INIS)

Arora, H.C.; Rao, G.N.

1981-01-01

4-Acylpyrazolones like 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP), 1-phenyl-3-methyl-4-p-nitrobenzoyl-5-pyrazolone (PMNP) and 1-phenyl-3-methyl-4-(3,5 dinitrobenzoyl)-5-pyrazolone (PMDP) have been synthesized and developed as gravimetric reagents for the determination of U(VI) and Th(IV). Uranium(VI) is almost quantitatively precipitated with PMBP, PMNP, and PMDP at pH 2.20, 1.85 and 1.70 respectively. The pH values for the complete precipitation of thorium(IV) with PMBP, PMNP and PMDP are 2.90, 2.75 and 2.50 respectively. PMBP has proved to be an efficient ligand for gravimetric determination of U(VI) by direct weighing method after drying at 100 +- 10 deg C. The percentage relative error varies from 0.4 to 1.6 in the determination of U(VI) by this method. The effect of a number of interfering ions on the precipitation of U(VI) by PMBP has been reported. (author)

ViCTree: An automated framework for taxonomic classification from protein sequences.

Science.gov (United States)

Modha, Sejal; Thanki, Anil; Cotmore, Susan F; Davison, Andrew J; Hughes, Joseph

2018-02-20

The increasing rate of submission of genetic sequences into public databases is providing a growing resource for classifying the organisms that these sequences represent. To aid viral classification, we have developed ViCTree, which automatically integrates the relevant sets of sequences in NCBI GenBank and transforms them into an interactive maximum likelihood phylogenetic tree that can be updated automatically. ViCTree incorporates ViCTreeView, which is a JavaScript-based visualisation tool that enables the tree to be explored interactively in the context of pairwise distance data. To demonstrate utility, ViCTree was applied to subfamily Densovirinae of family Parvoviridae. This led to the identification of six new species of insect virus. ViCTree is open-source and can be run on any Linux- or Unix-based computer or cluster. A tutorial, the documentation and the source code are available under a GPL3 license, and can be accessed at http://bioinformatics.cvr.ac.uk/victree_web/. sejal.modha@glasgow.ac.uk.

Contribution of Extracellular Polymeric Substances from Shewanella sp. HRCR-1 Biofilms to U(VI) Immobilization

Energy Technology Data Exchange (ETDEWEB)

Cao, Bin; Ahmed, B.; Kennedy, David W.; Wang, Zheming; Shi, Liang; Marshall, Matthew J.; Fredrickson, Jim K.; Isern, Nancy G.; Majors, Paul D.; Beyenal, Haluk

2011-06-05

The goal of this study was to quantify the contribution of extracellular polymeric substances (EPS) in U(VI) immobilization by Shewanella sp. HRCR-1. Through comparison of U(VI) immobilization using cells with bound EPS (bEPS) and cells without EPS, we showed that i) bEPS from Shewanella sp. HRCR-1 biofilms contributed significantly to U(VI) immobilization, especially at low initial U(VI) concentrations, through both sorption and reduction; ii) bEPS could be considered as a functional extension of the cells for U(VI) immobilization and they likely play more important roles at initial U(VI) concentrations; and iii) U(VI) reduction efficiency was found to be dependent upon initial U(VI) concentration and the efficiency decreased at lower concentrations. To quantify relative contribution of sorption and reduction in U(VI) immobilization by EPS fractions, we isolated loosely associated EPS (laEPS) and bEPS from Shewanella sp. HRCR-1 biofilms grown in a hollow fiber membrane biofilm reactor and tested their reactivity with U(V). We found that, when in reduced form, the isolated cell-free EPS fractions could reduce U(VI). Polysaccharides in the EPS likely contributed to U(VI) sorption and dominated reactivity of laEPS while redox active components (e.g., outer membrane c-type cytochromes), especially in bEPS, might facilitate U(VI) reduction.

Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen.

Directory of Open Access Journals (Sweden)

Peter J Hart

Full Text Available Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against Vi confer protection. Here we investigate the role of Vi capsule and antibodies against Vi and O:9 in antibody-dependent complement- and phagocyte-mediated killing of Salmonella. Using isogenic Vi-expressing and non-Vi-expressing derivatives of S. Typhi and S. Typhimurium, we show that S. Typhi is inherently more sensitive to serum and blood than S. Typhimurium. Vi expression confers increased resistance to both complement- and phagocyte-mediated modalities of antibody-dependent killing in human blood. The Vi capsule is associated with reduced C3 and C5b-9 deposition, and decreased overall antibody binding to S. Typhi. However, purified human anti-Vi antibodies in the presence of complement are able to kill Vi-expressing Salmonella, while killing by anti-O:9 antibodies is inversely related to Vi expression. Human serum depleted of antibodies to antigens other than Vi retains the ability to kill Vi-expressing bacteria. Our findings support a protective role for Vi capsule in preventing complement and phagocyte killing of Salmonella that can be overcome by specific anti-Vi antibodies, but only to a limited extent by anti-O:9 antibodies.

Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen.

Science.gov (United States)

Hart, Peter J; O'Shaughnessy, Colette M; Siggins, Matthew K; Bobat, Saeeda; Kingsley, Robert A; Goulding, David A; Crump, John A; Reyburn, Hugh; Micoli, Francesca; Dougan, Gordon; Cunningham, Adam F; MacLennan, Calman A

2016-01-01

Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against Vi confer protection. Here we investigate the role of Vi capsule and antibodies against Vi and O:9 in antibody-dependent complement- and phagocyte-mediated killing of Salmonella. Using isogenic Vi-expressing and non-Vi-expressing derivatives of S. Typhi and S. Typhimurium, we show that S. Typhi is inherently more sensitive to serum and blood than S. Typhimurium. Vi expression confers increased resistance to both complement- and phagocyte-mediated modalities of antibody-dependent killing in human blood. The Vi capsule is associated with reduced C3 and C5b-9 deposition, and decreased overall antibody binding to S. Typhi. However, purified human anti-Vi antibodies in the presence of complement are able to kill Vi-expressing Salmonella, while killing by anti-O:9 antibodies is inversely related to Vi expression. Human serum depleted of antibodies to antigens other than Vi retains the ability to kill Vi-expressing bacteria. Our findings support a protective role for Vi capsule in preventing complement and phagocyte killing of Salmonella that can be overcome by specific anti-Vi antibodies, but only to a limited extent by anti-O:9 antibodies.

Spectroscopic confirmation of uranium(VI)-carbonato adsorption complexes on hematite

Science.gov (United States)

Bargar, John R.; Reitmeyer, Rebecca; Davis, James A.

1999-01-01

Evaluating societal risks posed by uranium contamination from waste management facilities, mining sites, and heavy industry requires knowledge about uranium transport in groundwater, often the most significant pathway of exposure to humans. It has been proposed that uranium mobility in aquifers may be controlled by adsorption of U(VI)−carbonato complexes on oxide minerals. The existence of such complexes has not been demonstrated, and little is known about their compositions and reaction stoichiometries. We have used attenuated total reflectance Fourier transform infrared (ATR-FTIR) and extended X-ray absorption fine structure (EXAFS) spectroscopies to probe the existence, structures, and compositions of ≡FeOsurface−U(VI)−carbonato complexes on hematite throughout the pH range of uranyl uptake under conditions relevant to aquifers. U(VI)−carbonato complexes were found to be the predominant adsorbed U(VI) species at all pH values examined, a much wider pH range than previously postulated based on analogy to aqueous U(VI)−carbonato complexes, which are trace constituents at pH carbonato complexes may be of major importance to the groundwater transport of similar actinide contaminants such as neptunium and plutonium.

Bicarbonate Impact on U(VI) Bioreduction in a Shallow Alluvial Aquifer

Energy Technology Data Exchange (ETDEWEB)

Long, Philip E.; Williams, Kenneth H.; Davis, James A.; Fox, Patricia M.; Wilkins, Michael J.; Yabusaki, Steven B.; Fang, Yilin; Waichler, Scott R.; Berman, Elena S.; Gupta, Manish; Chandler, Darrell P.; Murray, Christopher J.; Peacock, Aaron D.; Giloteaux, L.; Handley, Kim M.; Lovley, Derek R.; Banfield, Jillian F.

2015-02-01

Field-scale biostimulation and desorption tracer experiments conducted in a uranium (U) contaminated, shallow alluvial aquifer have provided insight into the coupling of microbiology, biogeochemistry, and hydrogeology that control U mobility in the subsurface. Initial experiments successfully tested the concept that Fe-reducing bacteria such as Geobacter sp. could enzymatically reduce soluble U(VI) to insoluble U(IV) during in situ electron donor amendment (Anderson et al. 2003, Williams et al. 2011). In parallel, in situ desorption tracer tests using bicarbonate amendment demonstrated rate-limited U(VI) desorption (Fox et al. 2012). These results and prior laboratory studies underscored the importance of enzymatic U(VI)-reduction and suggested the ability to combine desorption and bioreduction of U(VI). Here we report the results of a new field experiment in which bicarbonate-promoted uranium desorption and acetate amendment were combined and compared to an acetate amendment-only experiment in the same experimental plot. Results confirm that bicarbonate amendment to alluvial aquifer desorbs U(VI) and increases the abundance of Ca-uranyl-carbonato complexes. At the same time, that the rate of acetate-promoted enzymatic U(VI) reduction was greater in the presence of added bicarbonate in spite of the increased dominance of Ca-uranyl-carbonato aqueous complexes. A model-simulated peak rate of U(VI) reduction was ~3.8 times higher during acetate-bicarbonate treatment than under acetate-only conditions. Lack of consistent differences in microbial community structure between acetate-bicarbonate and acetate-only treatments suggest that a significantly higher rate of U(VI) reduction the bicarbonate-impacted sediment may be due to a higher intrinsic rate of microbial reduction induced by elevated concentrations of the bicarbonate oxyanion. The findings indicate that bicarbonate amendment may be useful in improving the engineered bioremediation of uranium in aquifers.

Bicarbonate impact on U(VI) bioreduction in a shallow alluvial aquifer

Science.gov (United States)

Long, Philip E.; Williams, Kenneth H.; Davis, James A.; Fox, Patricia M.; Wilkins, Michael J.; Yabusaki, Steven B.; Fang, Yilin; Waichler, Scott R.; Berman, Elena S. F.; Gupta, Manish; Chandler, Darrell P.; Murray, Chris; Peacock, Aaron D.; Giloteaux, Ludovic; Handley, Kim M.; Lovley, Derek R.; Banfield, Jillian F.

2015-02-01

Field-scale biostimulation and desorption tracer experiments conducted in a uranium (U) contaminated, shallow alluvial aquifer have provided insight into the coupling of microbiology, biogeochemistry, and hydrogeology that control U mobility in the subsurface. Initial experiments successfully tested the concept that Fe-reducing bacteria such as Geobacter sp. could enzymatically reduce soluble U(VI) to insoluble U(IV) during in situ electron donor amendment (Anderson et al., 2003; Williams et al., 2011). In parallel, in situ desorption tracer tests using bicarbonate amendment demonstrated rate-limited U(VI) desorption (Fox et al., 2012). These results and prior laboratory studies underscored the importance of enzymatic U(VI)-reduction and suggested the ability to combine desorption and bioreduction of U(VI). Here we report the results of a new field experiment in which bicarbonate-promoted uranium desorption and acetate amendment were combined and compared to an acetate amendment-only experiment in the same experimental plot. Results confirm that bicarbonate amendment to alluvial aquifer sediments desorbs U(VI) and increases the abundance of Ca-uranyl-carbonato complexes. At the same time, the rate of acetate-promoted enzymatic U(VI) reduction was greater in the presence of added bicarbonate in spite of the increased dominance of Ca-uranyl-carbonato aqueous complexes. A model-simulated peak rate of U(VI) reduction was ∼3.8 times higher during acetate-bicarbonate treatment than under acetate-only conditions. Lack of consistent differences in microbial community structure between acetate-bicarbonate and acetate-only treatments suggest that a significantly higher rate of U(VI) reduction in the bicarbonate-impacted sediment may be due to a higher intrinsic rate of microbial reduction induced by elevated concentrations of the bicarbonate oxyanion. The findings indicate that bicarbonate amendment may be useful in improving the engineered bioremediation of uranium in

Mechanism of uranium (VI) removal by two anaerobic bacterial communities

Energy Technology Data Exchange (ETDEWEB)

Martins, Monica [Centro de Ciencias do Mar, Universidade do Algarve, FCT-DQF (edificio 8), Campus de Gambelas, 8005-139 Faro (Portugal); Faleiro, Maria Leonor [IBB - Centro de Biomedicina Molecular e Estrutural, Universidade do Algarve, FCT, Campus de Gambelas, 8005-139 Faro (Portugal); Costa, Ana M. Rosa da [Centro de Investigacao em Quimica do Algarve, Universidade do Algarve, FCT, DQF, Campus de Gambelas, 8005-139 Faro (Portugal); Chaves, Sandra; Tenreiro, Rogerio [Universidade de Lisboa, Faculdade de Ciencias, Centro de Biodiversidade, Genomica Integrativa e Funcional (BioFIG), Campus de FCUL, Campo Grande, 1749-016 Lisboa (Portugal); Matos, Antonio Pedro [Servico de Anatomia Patologica, Hospital Curry Cabral, Lisboa (Portugal); Costa, Maria Clara, E-mail: mcorada@ualg.pt [Centro de Ciencias do Mar, Universidade do Algarve, FCT-DQF (edificio 8), Campus de Gambelas, 8005-139 Faro (Portugal)

2010-12-15

The mechanism of uranium (VI) removal by two anaerobic bacterial consortia, recovered from an uncontaminated site (consortium A) and other from an uranium mine (consortium U), was investigated. The highest efficiency of U (VI) removal by both consortia (97%) occurred at room temperature and at pH 7.2. Furthermore, it was found that U (VI) removal by consortium A occurred by enzymatic reduction and bioaccumulation, while the enzymatic process was the only mechanism involved in metal removal by consortium U. FTIR analysis suggested that after U (VI) reduction, U (IV) could be bound to carboxyl, phosphate and amide groups of bacterial cells. Phylogenetic analysis of 16S rRNA showed that community A was mainly composed by bacteria closely related to Sporotalea genus and Rhodocyclaceae family, while community U was mainly composed by bacteria related to Clostridium genus and Rhodocyclaceae family.

Mechanism of uranium (VI) removal by two anaerobic bacterial communities

International Nuclear Information System (INIS)

Martins, Monica; Faleiro, Maria Leonor; Costa, Ana M. Rosa da; Chaves, Sandra; Tenreiro, Rogerio; Matos, Antonio Pedro; Costa, Maria Clara

2010-01-01

The mechanism of uranium (VI) removal by two anaerobic bacterial consortia, recovered from an uncontaminated site (consortium A) and other from an uranium mine (consortium U), was investigated. The highest efficiency of U (VI) removal by both consortia (97%) occurred at room temperature and at pH 7.2. Furthermore, it was found that U (VI) removal by consortium A occurred by enzymatic reduction and bioaccumulation, while the enzymatic process was the only mechanism involved in metal removal by consortium U. FTIR analysis suggested that after U (VI) reduction, U (IV) could be bound to carboxyl, phosphate and amide groups of bacterial cells. Phylogenetic analysis of 16S rRNA showed that community A was mainly composed by bacteria closely related to Sporotalea genus and Rhodocyclaceae family, while community U was mainly composed by bacteria related to Clostridium genus and Rhodocyclaceae family.

Cr(VI) occurrence and geochemistry in water from public-supply wells in California

Science.gov (United States)

Izbicki, John; Wright, Michael; Seymour, Whitney A.; McCleskey, R. Blaine; Fram, Miranda S.; Belitz, Kenneth; Esser, Bradley K.

2015-01-01

Hexavalent chromium, Cr(VI), in 918 wells sampled throughout California between 2004 and 2012 by the Groundwater Ambient Monitoring and Assessment-Priority Basin Project (GAMA-PBP) ranged from less than the study reporting limit of 1 microgram per liter (μg/L) to 32 μg/L. Statewide, Cr(VI) was reported in 31 percent of wells and equaled or exceeded the recently established (2014) California Maximum Contaminant Level (MCL) for Cr(VI) of 10 μg/L in 4 percent of wells. Cr(VI) data collected for regulatory purposes overestimated Cr(VI) occurrence compared to spatially-distributed GAMA-PBP data. Ninety percent of chromium was present as Cr(VI), which was detected more frequently and at higher concentrations in alkaline (pH ≥ 8), oxic water; and more frequently in agricultural and urban land uses compared to native land uses. Chemical, isotopic (tritium and carbon-14), and noble-gas data show high Cr(VI) in water from wells in alluvial aquifers in the southern California deserts result from long groundwater-residence times and geochemical reactions such as silicate weathering that increase pH, while oxic conditions persist. High Cr(VI) in water from wells in alluvial aquifers along the west-side of the Central Valley results from high-chromium in source rock eroded to form those aquifers, and areal recharge processes (including irrigation return) that can mobilize chromium from the unsaturated zone. Cr(VI) co-occurred with oxyanions having similar chemistry, including vanadium, selenium, and uranium. Cr(VI) was positively correlated with nitrate, consistent with increased concentrations in areas of agricultural land use and mobilization of chromium from the unsaturated zone by irrigation return.

Oxidation of ciprofloxacin and enrofloxacin by ferrate(VI): Products identification, and toxicity evaluation

International Nuclear Information System (INIS)

Yang, Bin; Kookana, Rai S.; Williams, Mike; Ying, Guang-Guo; Du, Jun; Doan, Hai; Kumar, Anupama

2016-01-01

Ferrate(VI) (Fe(VI)) has been known to react with emerging organic contaminants containing electron-rich organic moieties, such as phenols, anilines, olefins, reduced sulfur and deprotonated amines. Oxidation of fluoroquinolone antibiotics, ciprofloxacin (CIP) and enrofloxacin (ENR), by Fe(VI) were investigated for their reaction products and toxicity changes as well as biodegradability of these products. Ten products were identified for both CIP and ENR reactions with Fe(VI) using a high-resolution accurate-mass Orbitrap mass analyzer. Structural changes to the CIP and ENR molecule included dealkylation, formation of alcohols and amides in piperazine ring and oxygen transfer to the double bond in quinolone structure. An enamine formation mechanism was tentatively proposed to facilitate the interpretation of CIP and ENR oxidation pathways. Toxicity evaluation using Microbial Assay for toxicity Risk Assessment (MARA) bioassay indicated that Fe(VI) oxidation products of CIP and ENR contributed negligible antibacterial potency and Fe(VI) oxidation treatment can remove the residual toxicity of CIP and ENR impacted source waters. The Fe(VI) oxidation treatment resulted in formation of relatively more biodegradable products (based on in silico assessment) than their corresponding parent compounds. The results showed that Fe(VI) has a good potential to degrade fluoroquinolone antibiotics and their antimicrobial potency in natural waters.

Oxidation of ciprofloxacin and enrofloxacin by ferrate(VI): Products identification, and toxicity evaluation

Energy Technology Data Exchange (ETDEWEB)

Yang, Bin, E-mail: Bin.Yang@csiro.au [CSIRO Land and Water, Waite Campus, PMB 2, Glen Osmond, South Australia 5064 (Australia); Kookana, Rai S.; Williams, Mike [CSIRO Land and Water, Waite Campus, PMB 2, Glen Osmond, South Australia 5064 (Australia); Ying, Guang-Guo [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Du, Jun; Doan, Hai; Kumar, Anupama [CSIRO Land and Water, Waite Campus, PMB 2, Glen Osmond, South Australia 5064 (Australia)

2016-12-15

Ferrate(VI) (Fe(VI)) has been known to react with emerging organic contaminants containing electron-rich organic moieties, such as phenols, anilines, olefins, reduced sulfur and deprotonated amines. Oxidation of fluoroquinolone antibiotics, ciprofloxacin (CIP) and enrofloxacin (ENR), by Fe(VI) were investigated for their reaction products and toxicity changes as well as biodegradability of these products. Ten products were identified for both CIP and ENR reactions with Fe(VI) using a high-resolution accurate-mass Orbitrap mass analyzer. Structural changes to the CIP and ENR molecule included dealkylation, formation of alcohols and amides in piperazine ring and oxygen transfer to the double bond in quinolone structure. An enamine formation mechanism was tentatively proposed to facilitate the interpretation of CIP and ENR oxidation pathways. Toxicity evaluation using Microbial Assay for toxicity Risk Assessment (MARA) bioassay indicated that Fe(VI) oxidation products of CIP and ENR contributed negligible antibacterial potency and Fe(VI) oxidation treatment can remove the residual toxicity of CIP and ENR impacted source waters. The Fe(VI) oxidation treatment resulted in formation of relatively more biodegradable products (based on in silico assessment) than their corresponding parent compounds. The results showed that Fe(VI) has a good potential to degrade fluoroquinolone antibiotics and their antimicrobial potency in natural waters.

A Salmonella Typhimurium-Typhi genomic chimera: a model to study Vi polysaccharide capsule function in vivo.

Directory of Open Access Journals (Sweden)

Angela M Jansen

2011-07-01

Full Text Available The Vi capsular polysaccharide is a virulence-associated factor expressed by Salmonella enterica serotype Typhi but absent from virtually all other Salmonella serotypes. In order to study this determinant in vivo, we characterised a Vi-positive S. Typhimurium (C5.507 Vi(+, harbouring the Salmonella pathogenicity island (SPI-7, which encodes the Vi locus. S. Typhimurium C5.507 Vi(+ colonised and persisted in mice at similar levels compared to the parent strain, S. Typhimurium C5. However, the innate immune response to infection with C5.507 Vi(+ and SGB1, an isogenic derivative not expressing Vi, differed markedly. Infection with C5.507 Vi(+ resulted in a significant reduction in cellular trafficking of innate immune cells, including PMN and NK cells, compared to SGB1 Vi(- infected animals. C5.507 Vi(+ infection stimulated reduced numbers of TNF-α, MIP-2 and perforin producing cells compared to SGB1 Vi(-. The modulating effect associated with Vi was not observed in MyD88(-/- and was reduced in TLR4(-/- mice. The presence of the Vi capsule also correlated with induction of the anti-inflammatory cytokine IL-10 in vivo, a factor that impacted on chemotaxis and the activation of immune cells in vitro.

Uranium(VI) adsorption properties of a chelating resin containing polyamine-substituted methylphosphonic acid moiety

International Nuclear Information System (INIS)

Matsuda, Masaaki; Akiyoshi, Yoshirou

1991-01-01

Uranium(VI) adsorption and desorption properties of a chelating resin containing polyamine-substituted methylphosphonic acid moiety of 2.29 mmol/g-resin (APA) were examined. Uranium(VI) adsorption properties of several ion exchange resins and extractant agents which were known as excellent adsorbents for uranium(VI), were examined together for a comparison with those of APA. Uranium(VI) adsorption capacity of APA at the concentration of 100 mg·dm -3 -uranium(VI) in 100 g·dm -3 -H 2 SO 4 aq. soln., 190 g·dm -3 -H 3 PO 4 aq. soln. and uranium enriched sea water, was 0.2, 0.05 and 0.05 mmol·g -1 respectively. The adsorption capacity of APA for uranium(VI) in these solutions was larger than that of another adsorbents, except the adsorption of uranium(VI) in enriched sea water on ion exchange resin containing phosphoric acid moiety (adsorption capacity ; 0.2 mmol·g -1 ). Uranium(VI) adsorption rate on APA was high and the relation between treatment time (t : min) and uranium(VI) concentration (y : mg·dm -3 ) in 100 g·dm -3 H 2 SO 4 aq. soln. after treatment, was shown as following equation, y=20 0.048t+1.90 (0≤t≤30). The adsorbed uranium(VI) on APA was able to be eluted with a mixed aq. soln. of hydrogen peroxide and sodium hydroxide and also was able to be eluted with an aq. alkaline soln. dissolved reduction agents such as sodium sulfite and hydrazine. From these results, it was thought that uranium(VI) adsorbed on APA was eluted due to the reduction to uranium(VI) by these eluents. (author)

Group IB Organometallic Chemistry XXXIV: Thermal behavior and chemical reactivity of tetranuclear Me2N-substituted diarylpropenylcopper-copper anion (Vi2Cu4X2) and mixed diarylpropenyl/organocopper (Vi2Cu4R2) compounds

NARCIS (Netherlands)

Koten, G. van; Hoedt, R.W.M. ten; Noltes, J.G.

1980-01-01

Thermal decomposition of configurationally pure 1, 2-diarylpropenylcopper compounds Z-Vi{2}CU{4}Br{2} and Z-Vi{2}Cu{4}R{2} [Vi @? (2-Me{2}NC{6}H{4})C@?C(Me)-(C{6}H{4}Me-4), R @? 2-Me{2}NC{6}H{4} or 4-MeC{6}H{4}C@?C] predominantly results in the formation of ViH. In contrast, only dimers (ViVi) were

Oxidação de microcistinas-LR em águas pelo íon ferrato(VI Aqueous oxidation of microcystin-LR by ferrate(VI

Directory of Open Access Journals (Sweden)

Sérgio João de Luca

2010-03-01

Full Text Available Toxinas de cianobactérias têm se tornado um grave problema na produção segura de água para consumo humano e animal. Técnicas convencionais de tratamento falham em atingir padrões de potabilidade. O ferrato(VI de potássio, um composto oxidante e coagulante, mostra potencialidade no tratamento de águas contaminadas. Neste trabalho, são apresentados resultados da oxidação pelo ferrato(VI de uma toxina gerada por cianobactérias, a microcistina-LR. Ensaios de cinética de oxidação e de teste de jarros mostram um valor médio de 0,012 min-1 para a constante de taxa de reação de pseudoprimeira ordem, para concentrações de MC-LR de 100 a 200 µg.L-1 na água bruta. Dosagens de 1,6 a 5,0 mg.L-1 de ferrato(VI sugerem o atendimento ao padrão de potabilidade para microcistinas, mostrando que o oxidante poderá ser empregado como coadjuvante no tratamento de água.Algae toxins are becoming a severe problem in the water treatment industry, especially for human and animal consumption. Traditional treatment processes have failed in complying with water supply standards. Potassium ferrate(VI is a powerful oxidant, disinfectant and, also, a coagulant. In this paper, the results of microcystin-LR oxidation by ferrate(VI ion are presented. Kinetic and jar tests showed a average value of 0,012 min-1 for the pseudo first order reaction rate constant, for 100 and 200 µg.L-1 concentration of MC-LR. Ferrate(VI dosages between 1.6 and 5.0 mg.L-1 suggest that water supply standards for MC-LR can be reached, which means that the oxidant may be employed as coadjuvant in water treatment.

Retention of uranium(VI) by laumontite, a fracture-filling material of granite

International Nuclear Information System (INIS)

Baik, M.H.; Lee, S.Y.; Shon, W.J.

2009-01-01

Retention of U(VI) by laumontite, a fracture-filling material of granite as investigated by conducting dynamic and batch sorption experiments in a love-box using a granite core with a natural fracture. The hydrodynamic properties of the granite core were obtained from the elution curve of a on-sorbing tracer, Br - . The elution curve of U(VI) showed a similar behavior to Br - . This reveals that the retention of U(VI) by the fracture-filling material was not significant when migrating through the fracture at a given condition. From the dynamic sorption experiment, the retardation factor R a and the distribution coefficient K a of U(VI) were obtained as about 2.9 and 0.16 cm, respectively. The distribution coefficient K d ) of U(VI) onto laumontite obtained by conducting a batch sorption experiment resulted in a small value of 2.3±0.5 mL/g. This low K d value greed with the result of the dynamic sorption experiment. For the distribution of uranium on the granite surface investigated by an X-ray image mapping, the fracture region filled with laumontite showed a relatively lower content of uranium compared to the surrounding granite surface. Thus, the low retention of U(VI) by the fracture-filling material can be explained by following two mechanisms. One is that U(VI) exists as anionic uranyl hydroxides or uranyl carbonates at a given groundwater condition and the other is the remarkably low sorption capacity of the laumontite for U(VI). author)

Fluorescent silver nanoclusters for ultrasensitive determination of chromium(VI) in aqueous solution

International Nuclear Information System (INIS)

Zhang, Jian Rong; Zeng, Ai Lian; Luo, Hong Qun; Li, Nian Bing

2016-01-01

Highlights: • Fluorescent Ag nanoclusters were first applied to Cr(VI) detection. • The proposed method is simple, rapid, and environmentally friendly. • The sensor shows a wide linear range, low detection limit, and good selectivity. • The system can also be used for the indirect assay of total chromium and Cr(III). • The analyses in real water samples are satisfactory. - Abstract: In this work, a simple and sensitive Cr(VI) sensor is proposed based on fluorescent polyethyleneimine-stabilized Ag nanoclusters, which allows the determination over a wide concentration range of 0.1 nM–3.0 μM and with a detection limit as low as 0.04 nΜ and a good selectivity. The quenching mechanism was discussed in terms of the absorption and fluorescence spectra, suggesting that Cr(VI) is connected to Ag nanoclusters by hydrogen bond between the oxygen atom at the vertex of tetrahedron structure of Cr(VI) and the amino nitrogen of polyethyleneimine that surrounded Ag nanoclusters and electron transfer from Ag nanoclusters to highly electron-deficient Cr(VI) results in fluorescence quenching. Despite the failure to quench the fluorescence efficiently, Cr(III) can also be measured using the proposed Ag nanoclusters by being oxidized to Cr(VI) in alkaline solution (pH ∼9) containing H 2 O 2 . Therefore, our approach could be used to detect Cr(VI), Cr(III) and the total chromium level in aqueous solution. In addition, Cr(VI) analysis in real water samples were satisfactory, indicating this method could be practically promising for chromium measurements.

Natural and man-made hexavalent chromium, Cr(VI), in groundwater near a mapped plume, Hinkley, California—study progress as of May 2017, and a summative-scale approach to estimate background Cr(VI) concentrations

Science.gov (United States)

Izbicki, John A.; Groover, Krishangi D.

2018-03-22

This report describes (1) work done between January 2015 and May 2017 as part of the U.S. Geological Survey (USGS) hexavalent chromium, Cr(VI), background study and (2) the summative-scale approach to be used to estimate the extent of anthropogenic (man-made) Cr(VI) and background Cr(VI) concentrations near the Pacific Gas and Electric Company (PG&E) natural gas compressor station in Hinkley, California. Most of the field work for the study was completed by May 2017. The summative-scale approach and calculation of Cr(VI) background were not well-defined at the time the USGS proposal for the background Cr(VI) study was prepared but have since been refined as a result of data collected as part of this study. The proposed summative scale consists of multiple items, formulated as questions to be answered at each sampled well. Questions that compose the summative scale were developed to address geologic, hydrologic, and geochemical constraints on Cr(VI) within the study area. Each question requires a binary (yes or no) answer. A score of 1 will be assigned for an answer that represents data consistent with anthropogenic Cr(VI); a score of –1 will be assigned for an answer that represents data inconsistent with anthropogenic Cr(VI). The areal extent of anthropogenic Cr(VI) estimated from the summative-scale analyses will be compared with the areal extent of anthropogenic Cr(VI) estimated on the basis of numerical groundwater flow model results, along with particle-tracking analyses. On the basis of these combined results, background Cr(VI) values will be estimated for “Mojave-type” deposits, and other deposits, in different parts of the study area outside the summative-scale mapped extent of anthropogenic Cr(VI).

Effect of Salicylic and Picolinic Acids on the Adsorption of U(VI) onto Oxides

International Nuclear Information System (INIS)

Park, Kyoung Kyun; Jung, Euo Chang; Cho, Hye Ryun; Song, Kyu Seok

2009-01-01

The effect of organic acids on the adsorption of U(VI) onto oxide surfaces (TiO 2 (anatase), SiO 2 (amorphous) and Al 2 O-3(amorphous)) has been investigated. Two different organic acids, salicylic and picolinic acids, were used. Changes of adsorption ratio of U(VI), which depend on the existence of organic acids in a sample, were measured as a function of pH. Quantities of adsorbed organic acids, which depend on the existence of U(VI) in a sample, were also measured as a function of pH. It is confirmed that the soluble complex formation of U(VI) with organic acids can deteriorate the adsorption of U(VI) onto TiO 2 surface. It is noteworthy that salicylic acid does not affect the adsorption of U(VI) onto SiO 2 surface, however, picolinic acid enhances the adsorption of U(VI) onto SiO 2 surface. The latter effect can be understood by considering the formation of a ternary surface complex on SiO 2 surface, which was confirmed by the co-adsorption of picolinic acid with U(VI) and the change in a fluorescence spectra of U(VI) on surface, In the case of Al 2 O-3, organic acids themselves were largely adsorbed onto a surface without deteriorating the adsorption of U(VI). This would support the possibility of a ternary surface complex formation on the Al 2 O-3 surface, and an additional spectroscopic study is required.

Role of paramagnetic chromium in chromium(VI)-induced damage in cultured mammalian cells.

OpenAIRE

Sugiyama, M

1994-01-01

Chromium(VI) compounds are known to be potent toxic and carcinogenic agents. Because chromium(VI) is easily taken up by cells and is subsequently reduced to chromium(III), the formation of paramagnetic chromium such as chromium(V) and chromium(III) is believed to play a role in the adverse biological effects of chromium(VI) compounds. The present report, uses electron spin resonance (ESR) spectroscopy; the importance of the role of paramagnetic chromium in chromium(VI)-induced damage in intac...

Environmental survey of Region VI, Haltenbanken, 2009; Miljoeundersoekelse i Region VI, Haltenbanken, 2009

Energy Technology Data Exchange (ETDEWEB)

Holm, May-Helen; Cochrane, Sabine; Mannvik, Hans-Petter; Wasbotten, Ingar Halvorsen

2010-07-01

There has been an environmental investigation in Region VI Halten Bank. This report presents the results of the chemical and biological assays performed on samples from a total of 316 stations in 16 fields and 15 regional stations. A status of environmental conditions in the region is given at the end of the report. (AG)

Biased Brownian motion mechanism for processivity and directionality of single-headed myosin-VI.

Science.gov (United States)

Iwaki, Mitsuhiro; Iwane, Atsuko Hikikoshi; Ikebe, Mitsuo; Yanagida, Toshio

2008-01-01

Conventional form to function as a vesicle transporter is not a 'single molecule' but a coordinated 'two molecules'. The coordinated two molecules make it complicated to reveal its mechanism. To overcome the difficulty, we adopted a single-headed myosin-VI as a model protein. Myosin-VI is an intracellular vesicle and organelle transporter that moves along actin filaments in a direction opposite to most other known myosin classes. The myosin-VI was expected to form a dimer to move processively along actin filaments with a hand-over-hand mechanism like other myosin organelle transporters. However, wild-type myosin-VI was demonstrated to be monomer and single-headed, casting doubt on its processivity. Using single molecule techniques, we show that green fluorescent protein (GFP)-fused single-headed myosin-VI does not move processively. However, when coupled to a 200 nm polystyrene bead (comparable to an intracellular vesicle in size) at a ratio of one head per bead, single-headed myosin-VI moves processively with large (40 nm) steps. Furthermore, we found that a single-headed myosin-VI-bead complex moved more processively in a high-viscous solution (40-fold higher than water) similar to cellular environment. Because diffusion of the bead is 60-fold slower than myosin-VI heads alone in water, we propose a model in which the bead acts as a diffusional anchor for the myosin-VI, enhancing the head's rebinding following detachment and supporting processive movement of the bead-monomer complex. This investigation will help us understand how molecular motors utilize Brownian motion in cells.

Molasses as an efficient low-cost carbon source for biological Cr(VI) removal

Energy Technology Data Exchange (ETDEWEB)

Michailides, Michail K. [Department of Environmental and Natural Resources Management, University of Patras, 2 G. Seferi Str., GR-30100 Agrinio (Greece); Tekerlekopoulou, Athanasia G., E-mail: atekerle@upatras.gr [Department of Environmental and Natural Resources Management, University of Patras, 2 G. Seferi Str., GR-30100 Agrinio (Greece); Akratos, Christos S.; Coles, Sandra [Department of Environmental and Natural Resources Management, University of Patras, 2 G. Seferi Str., GR-30100 Agrinio (Greece); Pavlou, Stavros [Institute of Chemical Engineering Sciences (FORTH/ICE-HT), Stadiou Str., Platani, P.O. Box 1414, GR-26504 Patras (Greece); Department of Chemical Engineering, University of Patras, GR-26504 Patras (Greece); Vayenas, Dimitrios V. [Department of Environmental and Natural Resources Management, University of Patras, 2 G. Seferi Str., GR-30100 Agrinio (Greece); Institute of Chemical Engineering Sciences (FORTH/ICE-HT), Stadiou Str., Platani, P.O. Box 1414, GR-26504 Patras (Greece)

2015-01-08

Highlights: • Suspended and attached growth reactors were examined for Cr(VI) bio-reduction. • Molasses was proved an efficient and very low cost carbon source. • Molasses was more efficient than sugar in enhancing Cr(VI) reduction. • SBR with recirculation was the most proper operating mode. - Abstract: In the present study, indigenous microorganisms from industrial sludge were used to reduce the activity of Cr(VI). Molasses, a by-product of sugar processing, was selected as the carbon source (instead of sugar used in a previous work) as it is a low-cost energy source for bioprocesses. Initially, experiments were carried out in suspended growth batch reactors for Cr(VI) concentrations of 1.5–110 mg/L. The time required for complete Cr(VI) reduction increased with initial Cr(VI) concentration. Initial molasses concentration was also found to influence the Cr(VI) reduction rate. The optimal concentration for all initial Cr(VI) concentrations tested was 0.8 gC/L. Experiments were also carried out in packed-bed reactors. Three different operating modes were used to investigate the optimal performance and efficiency of the filter, i.e. batch, continuous and SBR with recirculation. The latter mode with a recirculation rate of 0.5 L/min lead to significantly high Cr(VI) reduction rates (up to 135 g/m{sup 2} d). The results of this work were compared with those of a similar work using sugar as the carbon source and indicate that molasses could prove a feasible technological solution to a serious environmental problem.

Kinetic study of time-dependent fixation of U{sup VI} on biochar

Energy Technology Data Exchange (ETDEWEB)

Ashry, A. [Division of Agricultural and Environmental Sciences, School of Biosciences, University of Nottingham, Sutton Bonington, Leicestershire LE12 5RD (United Kingdom); Radiation Protection Department, Nuclear Research Centre, Egyptian Atomic Energy Authority, Cairo (Egypt); Bailey, E.H., E-mail: liz.bailey@nottingham.ac.uk [Division of Agricultural and Environmental Sciences, School of Biosciences, University of Nottingham, Sutton Bonington, Leicestershire LE12 5RD (United Kingdom); Chenery, S.R.N. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Young, S.D. [Division of Agricultural and Environmental Sciences, School of Biosciences, University of Nottingham, Sutton Bonington, Leicestershire LE12 5RD (United Kingdom)

2016-12-15

Biochar, a by-product from the production of biofuel and syngas by gasification, was tested as a material for adsorption and fixation of U{sup VI} from aqueous solutions. A batch experiment was conducted to study the factors that influence the adsorption and time-dependent fixation on biochar at 20 °C, including pH, initial concentration of U{sup VI} and contact time. Uranium (U{sup VI}) adsorption was highly dependent on pH but adsorption on biochar was high over a wide range of pH values, from 4.5 to 9.0, and adsorption strength was time-dependent over several days. The experimental data for pH > 7 were most effectively modelled using a Freundlich adsorption isotherm coupled to a reversible first order kinetic equation to describe the time-dependent fixation of U{sup VI} within the biochar structure. Desorption experiments showed that U{sup VI} was only sparingly desorbable from the biochar with time and isotopic dilution with {sup 233}U{sup VI} confirmed the low, or time-dependent, lability of adsorbed {sup 238}U{sup VI}. Below pH 7 the adsorption isotherm trend suggested precipitation, rather than true adsorption, may occur. However, across all pH values (4.5-9) measured saturation indices suggested precipitation was possible: autunite below pH 6.5 and either swartzite, liebigite or bayleyite above pH 6.5.

Raman spectrometric determination of Pu(VI) and Pu(V) in nitric acid solutions

International Nuclear Information System (INIS)

Gantner, E.; Freudenberger, M.; Steinert, D.; Ache, H.J.

1987-03-01

The determination of Pu(VI) in nitric acid solutions by spontaneous Laser Raman Spectrometry (LRS) was investigated and a calibration curve was established using U(VI) as internal standard. In addition, the concentrations of Pu(VI) and Pu(V) as a function of time were measured by this method in Pu(VI) solutions of different acidity containing H 2 O 2 as the reducing agent. In solutions which are intensely coloured by the presence of Ru(NO) complexes Pu(VI) can also be determined by LRS using a Kr + laser as excitation source. In future experiments, the study of the Pu(IV)-interaction with Ru using LRS and spectrophotometry as analytical techniques is therefore intended. (orig.) [de

28 CFR 42.405 - Public dissemination of title VI information.

Science.gov (United States)

2010-07-01

... Federally Assisted Programs § 42.405 Public dissemination of title VI information. (a) Federal agencies... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Public dissemination of title VI information. 42.405 Section 42.405 Judicial Administration DEPARTMENT OF JUSTICE NONDISCRIMINATION; EQUAL...

ENDF-201: ENDF/B-VI summary documentation

International Nuclear Information System (INIS)

Rose, P.F.

1991-10-01

Responsibility for oversight of the ENDF/B Evaluated Nuclear Data file lies with the Cross Section Evaluation Working Group (CSEWG), which is comprised of representatives from various governmental and industrial laboratories in the United States. Individual evaluations are provided by scientists at several US laboratories, including significant contributions by scientists from all over the world. In addition, ENDF/B-VI includes for the first time complete evaluations for three materials that were provided from laboratories outside the US. All data are checked and reviewed by CSEWG, and the data file is maintained and issued by the National Nuclear Data Center at Brookhaven National Laboratory. The previous version of the library, ENDF/B-V, was issued in 1979, and two revisions to the data file were provided in subsequent years, the latest occurring in 1981. A total of 75 new or extensively modified neutron sublibrary evaluations are included in ENDF/B-VI, and are summarized in this document. One incident proton sublibrary is described for Fe 56 . The remaining evaluations in ENDF/B-VI have been carried over from earlier versions of ENDF, and have been updated to reflect the new formats. The release of ENDF/B-VI was carried out between January and June of 1990, with groups of materials being released on ''tapes.'' Table 1 is an index to the evaluation summaries, and includes the material identification or MAT number, the responsible laboratory, and the ''tape'' number. These evaluations have been released without restrictions on their distribution or use

ENDF-201: ENDF/B-VI summary documentation

Energy Technology Data Exchange (ETDEWEB)

Rose, P.F. (comp.)

1991-10-01

Responsibility for oversight of the ENDF/B Evaluated Nuclear Data file lies with the Cross Section Evaluation Working Group (CSEWG), which is comprised of representatives from various governmental and industrial laboratories in the United States. Individual evaluations are provided by scientists at several US laboratories, including significant contributions by scientists from all over the world. In addition, ENDF/B-VI includes for the first time complete evaluations for three materials that were provided from laboratories outside the US. All data are checked and reviewed by CSEWG, and the data file is maintained and issued by the National Nuclear Data Center at Brookhaven National Laboratory. The previous version of the library, ENDF/B-V, was issued in 1979, and two revisions to the data file were provided in subsequent years, the latest occurring in 1981. A total of 75 new or extensively modified neutron sublibrary evaluations are included in ENDF/B-VI, and are summarized in this document. One incident proton sublibrary is described for Fe{sup 56}. The remaining evaluations in ENDF/B-VI have been carried over from earlier versions of ENDF, and have been updated to reflect the new formats. The release of ENDF/B-VI was carried out between January and June of 1990, with groups of materials being released on tapes.'' Table 1 is an index to the evaluation summaries, and includes the material identification or MAT number, the responsible laboratory, and the tape'' number. These evaluations have been released without restrictions on their distribution or use.

ENDF-201: ENDF/B-VI summary documentation

Energy Technology Data Exchange (ETDEWEB)

Rose, P.F. [comp.

1991-10-01

Responsibility for oversight of the ENDF/B Evaluated Nuclear Data file lies with the Cross Section Evaluation Working Group (CSEWG), which is comprised of representatives from various governmental and industrial laboratories in the United States. Individual evaluations are provided by scientists at several US laboratories, including significant contributions by scientists from all over the world. In addition, ENDF/B-VI includes for the first time complete evaluations for three materials that were provided from laboratories outside the US. All data are checked and reviewed by CSEWG, and the data file is maintained and issued by the National Nuclear Data Center at Brookhaven National Laboratory. The previous version of the library, ENDF/B-V, was issued in 1979, and two revisions to the data file were provided in subsequent years, the latest occurring in 1981. A total of 75 new or extensively modified neutron sublibrary evaluations are included in ENDF/B-VI, and are summarized in this document. One incident proton sublibrary is described for Fe{sup 56}. The remaining evaluations in ENDF/B-VI have been carried over from earlier versions of ENDF, and have been updated to reflect the new formats. The release of ENDF/B-VI was carried out between January and June of 1990, with groups of materials being released on ``tapes.`` Table 1 is an index to the evaluation summaries, and includes the material identification or MAT number, the responsible laboratory, and the ``tape`` number. These evaluations have been released without restrictions on their distribution or use.

Teknologi Pengendalian Gulma Alang-alang dengan Tanaman Legum untuk Pertanian Tanaman Pangan

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Ishak Juarsah

2015-07-01

Full Text Available Di Indonesia, Alang-alang (Imperata cylindrica L. Beauv merupakan salah satu gulma terpenting dan termasuk sepuluh gulma bermasalah di dunia.  Melalui biji dan rimpang, alang-alang dapat tumbuh dan menyebar luas pada hampir semua kondisi lahan. Teknologi pengendalian alang-alang telah banyak dikenal namun belum dapat menjamin eradikasi populasi alang-alang secara berkelanjutan tanpa diikuti oleh kultur teknis dan pola budidaya tanaman pangan sepanjang tahun. Hasil penelitian menunjukan bahwa lahan alang-alang dapat dikendalikan/dikelola menjadi lahan produktif setelah direhabilitasi dengan tanaman legume (Mucuna sp. untuk usaha tani tanaman pangan lahan kering berorientasi konservasi tanah. Bahan hijauan tanaman Mucuna dapat meningkatkan kadar C-organik, memperbaiki sifat fisika, kimia tanah dan meningkatkan  produksi tanaman pangan. In Indonesia, Alang-alang (Imperata cylindrica L. Beauv is one of important weeds and included to ten most problematic weeds around the world. Through its seeds and roots, alang-alang can grow and expand in nearly all soil conditions. Many technologies for controlling have been known but can not ensure the eradication of weeds population, however the controlling via food crops cropping systems for the whole years is the best method so far to have sustainability of the agriculture land. Research showed that alang-alang area could be controlled/managed became more productive land after rehabilitation with legume (ie Mucuna sp. especially for dry land conservation oriented. Mucuna green materials might increase C-organic content, both soil chemical and physical improvement, furthermore increased foodcrops production.

Biological Cr(VI) removal using bio-filters and constructed wetlands.

Science.gov (United States)

Michailides, Michail K; Sultana, Mar-Yam; Tekerlekopoulou, Athanasia G; Akratos, Christos S; Vayenas, Dimitrios V

2013-01-01

The bioreduction of hexavalent chromium from aqueous solution was carried out using suspended growth and packed-bed reactors under a draw-fill operating mode, and horizontal subsurface constructed wetlands. Reactors were inoculated with industrial sludge from the Hellenic Aerospace Industry using sugar as substrate. In the suspended growth reactors, the maximum Cr(VI) reduction rate (about 2 mg/L h) was achieved for an initial concentration of 12.85 mg/L, while in the attached growth reactors, a similar reduction rate was achieved even with high initial concentrations (109 mg/L), thus confirming the advantage of these systems. Two horizontal subsurface constructed wetlands (CWs) pilot-scale units were also built and operated. The units contained fine gravel. One unit was planted with common reeds and one was kept unplanted. The mean influent concentrations of Cr(VI) were 5.61 and 5.47 mg/L for the planted and unplanted units, respectively. The performance of the planted CW units was very effective as mean Cr(VI) removal efficiency was 85% and efficiency maximum reached 100%. On the contrary, the unplanted CW achieved very low Cr(VI) removal with a mean value of 26%. Both attached growth reactors and CWs proved efficient and viable means for Cr(VI) reduction.

APLIKASI MODEL PENERIMAAN TEKNOLOGI DALAM PENGGUNAAN SOFTWARE AUDIT OLEH AUDITOR

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Dhini Suryandini

2012-03-01

Full Text Available Tujuan penelitian ini adalah untuk menguji faktor yang mempengaruhi penerimaan auditor dari perangkat lunak audit dengan menggunakan Model Penerimaan Teknologi (TAM. Data dikumpulkan dengan menggunakan metode survei melalui surat dan email yang dikirim ke auditor di 4 perusahaan-perusahaan CPA di Indonesia. Data dianalisis dengan menggunakan Partial Least Square (PLS. Metode tersebut merupakan metode alternatif Pemodelan Persamaan Struktur dengan menggunakan program aplikasi Smart PLS. Hasil penelitian ini menunjukkan bahwa ada hubungan positif antara perceived usefulness (PU dan attitude terhadap penggunaan audit software (ATT, antara perceived usefulness (PU dan actual use (AU, experience (EXP dan perceived usefulness (PU, dan computer-self-efficacy (CSE dan perceived ease of use (PEOU. Ada 2 faktor yang memiliki pengaruh signifikan baik secara langsung dan tidak langsung pada penerimaan auditor dari perangkat lunak audit. Perceived usefulnes mempunyai pengaruh positif secara langsung terhadap actual use (AU. The aim of this research is to test the factors, influencing the auditor acceptance of audit software by using Technology Acceptance Model (TAM. The data were collected by using survey method through mail and email delivered to the auditors in big 4 CPA’s firms in Indonesia. The data were analyzed by using Partial Least Square (PLS method. It is the alternative method of Structural Equation Modeling (SEM in which Smart PLS application program is applied. The results of this research indicate that there are positive relationship between perceived usefulness (PU and attitude to the use of the audit software (ATT, between perceived usefulness (PU and actual use (AU, between experience (EXP and perceived usefulness (PU, and between computer-self-efficacy (CSE and perceived ease of use (PEOU.  There are 2 factors that have significant influence on the auditor acceptance of audit software directly and indirectly. Perceived

VI Tallinna arhitektuuritriennaal / Leonhard Lapin

Index Scriptorium Estoniae

Lapin, Leonhard, 1947-

2005-01-01

15.-17. IX Tallinnas Niguliste kirikus toimuval VI Tallinna arhitektuuritriennaalil esinevad inglise arhitektuurikriitik Peter Davey, šveitsi arhitekt Peter Zumthor, soome arhitekt Juha Leviskä, eesti arhitekt Vilen Künnapu, eesti kunstiajaloolane Juhan Maiste jt. Külastatakse KUMU, tutvutab autor Pekka Vapaavuori

Extraction of uranium (VI) sulphate complexes by Adogen amines

Energy Technology Data Exchange (ETDEWEB)

Elyamani, I S; Abd Elmessieh, E N [Nuclear chemistry department, hot laboratories center, atomic energy authority, Cairo, (Egypt)

1995-10-01

The distribution of U(VI) between aqueous H{sub 2} So{sub 4} solutions and organic phases of adogen-368 has been described. The dependence of extraction on acidity, diluent type, metal and extractant concentrations was investigated. The possible extraction mechanism is discussed in the light of results obtained. The separation of U(VI) from rare earths is suggested. 5 figs., 1 tab.

Reduction of chromium (VI by the indirect action of Thiobacillus thioparus

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E. Donati

2003-03-01

Full Text Available The microbial reduction of chromium(VI to chromium(III has been one of the most widely studied forms of metal bioremediation. Recently, we have found that Thiobacillus ferrooxidans and Thiobacillus thiooxidans, growing on elemental sulphur, can indirectly promote chromium(VI reduction by producing reducing agents such as sulphite and thiosulphate, which abiotically reduce chromium(VI. Those species of Thiobacillus are acidophilic bacteria which grow optimally at pH values lower than 4. However, most of those reducing agents are stabilised at higher pH values. Thus, the present paper reports on the ability to reduce chromium(VI using another specie of Thiobacilli, Thiobacillus thioparus, which is able to grow at pH close to 7.0. T. thioparus cultures were carried out in a fermentation vessel containing medium and sulphur as the sole energy source and maintained at 30ºC and 400 rpm. The pH was adjusted to 6.0, 7.0 or 8.0 and maintained with the automatic addition of KOH. Our results show high chromium (VI reduction values (close to 100% at the end of bacterial growth at the three pH values. The results of these experiments are very promising for development of a microbiological process to be used in the detoxification of chromium(VI-polluted effluents.

CHROMIUM(VI REDUCTION BY A MIXED CULTURE OF SULFATE REDUCING BACTERIA DEVELOPED IN COLUMN REACTOR

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Cynthia Henny

2008-03-01

Full Text Available A lactate enriched mixed sulfate reducing bacteria (SRB culture was examined for the reduction of Cr(VI in a continuous flow system. The influent was mineral salts media added with lactate and sulfate with amounts of 8 and 6 mM respectively as electron donor and electron acceptor. The SRB culture was allowed to stabilize in the column before adding the Cr(VI to the influent. Chromium and sulfate reduction and lactate oxidation were examined by measuring the concentrations of Cr(Vl, sulfate and lactate in the influent and the effluent over time. The experiment was discontinued when Cr(VI concentration in the effiuent was breakthrough. In the absence of Cr(VI, sulfate was not completely reduced in the column, although lactate was completely oxidized and acetate as an intermediate product was not often detected. Almost all of Cr(VI loaded was reduced in the column seeded with the SRB culture at influent Cr(VI concentrations of 192,385 and769 mM. There was no significant Cr(VI loss in the control column, indicating that Cr(VI removal was due to the reduction of Cr(VI to Cr (lll by the SRB culture. The instantaneous Cr(VI removal decreased to a minimum of 32%, 24 days after the influent Cr(VI concentration was increased to 1540 mM, ancl sulfate removal efficiency decreased to a minimum of 17%. The SRB population in the column decreased 100 days after C(VI was added to the column. The total mass of Cr(VI reduced was approximately 878 mmol out of 881 mmol of Cr(Vl loaded in 116 days. The results clearly show that our developed SRB culture could reduced Cr(Vl considerably.

Studies on the kinetics of uranium (VI) electro-reduction and reextraction: Pt. 2

International Nuclear Information System (INIS)

Tong Jihong; Ma Xuquan; Tai Derong; Sun Shiren

1992-01-01

The kinetics of U(VI) reextraction and U(IV) extraction in the process of U(VI) electro-reduction with the system of HNO 3 -N 2 H 5 NO 3 (H 2 O)/UO 2 (NO 3 ) 2 -HNO 3 (30% TBP-OK) is investigated with a constant interfacial area cell (Lewis cell) with cathode and anode in it. According to the experimental results and data processing, the apparent activation energy of the U(VI) reextraction process is 36.02 kJ/nol. The U(VI) reextraction rate increases when the stirring speed of two phases increases. This process is mainly diffusion controlled. For the U(VI) extraction process, the apparent activation energy is 21.13 kJ/mol. The U(IV) extraction rate also increases when the stirring speed of two phases increases. This process is mainly diffusion controlled. The lower the potential of cathode is, the higher the rates of U(VI) reextraction and U(IV) extraction are

Kinetics and Products of Chromium(VI) Reduction by Iron(II/III)-Bearing Clay Minerals.

Science.gov (United States)

Joe-Wong, Claresta; Brown, Gordon E; Maher, Kate

2017-09-05

Hexavalent chromium is a water-soluble pollutant, the mobility of which can be controlled by reduction of Cr(VI) to less soluble, environmentally benign Cr(III). Iron(II/III)-bearing clay minerals are widespread potential reductants of Cr(VI), but the kinetics and pathways of Cr(VI) reduction by such clay minerals are poorly understood. We reacted aqueous Cr(VI) with two abiotically reduced clay minerals: an Fe-poor montmorillonite and an Fe-rich nontronite. The effects of ionic strength, pH, total Fe content, and the fraction of reduced structural Fe(II) [Fe(II)/Fe(total)] were examined. The last variable had the largest effect on Cr(VI) reduction kinetics: for both clay minerals, the rate constant of Cr(VI) reduction varies by more than 3 orders of magnitude with Fe(II)/Fe(total) and is described by a linear free energy relationship. Under all conditions examined, Cr and Fe K-edge X-ray absorption near-edge structure spectra show that the main Cr-bearing product is a Cr(III)-hydroxide and that Fe remains in the clay structure after reacting with Cr(VI). This study helps to quantify our understanding of the kinetics of Cr(VI) reduction by Fe(II/III)-bearing clay minerals and may improve predictions of Cr(VI) behavior in subsurface environments.

Polyaniline (PANI) modified bentonite by plasma technique for U(VI) removal from aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Liu, Xinghao [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900 (China); Intelligent Manufacturing Technology Research Institute, Hefei University of Technology, Hefei 230088 (China); Cheng, Cheng [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Xiao, Chengjian, E-mail: xiaocj@caep.cn [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900 (China); Shao, Dadong, E-mail: shaodadong@126.com [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Xu, Zimu, E-mail: xzm@mail.ustc.edu.cn [Intelligent Manufacturing Technology Research Institute, Hefei University of Technology, Hefei 230088 (China); Wang, Jiaquan; Hu, Shuheng [Intelligent Manufacturing Technology Research Institute, Hefei University of Technology, Hefei 230088 (China); Li, Xiaolong; Wang, Weijuan [Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang 621900 (China)

2017-07-31

Highlights: • PANI/bentonie can be synthesized by simple plasma technique. • PANI/bentonie has an excellent adsorption capacity for trace uranium in solution. • U(VI) adsorption on PANI/bentonite is a spontaneous and endothermic process. - Abstract: Polyaniline (PANI) modified bentonite (PANI/bentonie) was synthesized by plasma induced polymerization of aniline on bentonite surface, and applied to uptake of uranium(VI) ions from aqueous solution. The as-synthesized PANI/bentonie was characterized by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), thermal gravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). Batch adsorption technique was utilized to investigate the adsorption of U(VI) on bentonite and PANI/bentonite. The adsorption of U(VI) (10 mg/L) on PANI/bentonite surface is fairly depend on solution pH, ionic strength, and temperature in solution. The modified PANI on PANI/bentonite surface significantly enhances its adsorption capability for U(VI). The presence of humic acid (HA) can sound enhance U(VI) adsorption on PANI/bentonite at pH < 6.5 because of the strong complexation, and inhibits U(VI) adsorption at pH > 6.5. According to the thermodynamic parameters, the adsorption of U(VI) on PANI/bentonite surface is a spontaneous and endothermic process. The results highlight the application of PANI/bentonite composites as candidate material for the uptake of trace U(VI) from aqueous solution.

Study on Cr(VI) Leaching from Cement and Cement Composites

Science.gov (United States)

Palascakova, Lenka; Kanuchova, Maria

2018-01-01

This paper reports an experimental study on hexavalent chromium leaching from cement samples and cement composites containing silica fume and zeolite additions that were subjected to various leaching agents. The water-soluble Cr(VI) concentrations in cements ranged from 0.2 to 3.2 mg/kg and represented only 1.8% of the total chromium content. The presence of chromium compounds with both chromium oxidation states of III and VI was detected in the cement samples by X-ray photoelectron spectroscopy (XPS). Leaching tests were performed in a Britton-Robinson buffer to simulate natural conditions and showed increased dissolution of Cr(VI) up to 6 mg/kg. The highest amount of leached hexavalent chromium was detected after leaching in HCl. The findings revealed that the leaching of chromium from cements was higher by 55–80% than that from the cement composites. A minimum concentration was observed for all cement samples when studying the relationship between the soluble Cr(VI) and the cement storage time. PMID:29690550

Remediation of U(VI)-contaminated water using zero-valent iron

International Nuclear Information System (INIS)

Abdelouas, A.; Gong, W.; Lutze, W.; Nuttall, E.

1999-01-01

We investigated the possibility of U(VI) reduction by zero-valent iron (Fe 0 ). We conducted batch experiments with granular iron and solutions containing 0.25 and 9.3 mg L -1 U(VI) at 24 deg C. The solution pH ranges between 2 and 9. In all experiments uranium removal was complete within several hours to several days regardless of the pH value. The reduced uranium precipitated as poorly crystallized hydrated uraninite, UO 2 .nH 2 O. The reduction of U(VI) to U(IV) by Fe 0 was found to be the principal mechanism of U removal from the solution. Other mechanisms such as U(VI) sorption on the newly formed Fe(III) hydroxides are insignificant. These results show that zero-valent iron can be used to remedy U-contaminated waters from uranium mines and mill tailings sites, the pH of which usually ranges between 2 and 9. (authors)

A critical review of ferrate(VI)-based remediation of soil and groundwater.

Science.gov (United States)

Rai, Prabhat Kumar; Lee, Jechan; Kailasa, Suresh Kumar; Kwon, Eilhann E; Tsang, Yiu Fai; Ok, Yong Sik; Kim, Ki-Hyun

2018-01-01

Over the past few decades, diverse chemicals and materials such as mono- and bimetallic nanoparticles, metal oxides, and zeolites have been used for soil and groundwater remediation. Ferrate (Fe VI O 4 2- ) has been widely employed due to its high-valent iron (VI) oxo compound with high oxidation/reduction potentials. Ferrate has received attention for wide environmental applications including water purification and sewage sludge treatment. Ferrate provides great potential for diverse environmental applications without any environmental problems. Therefore, this paper provides comprehensive information on the recent progress on the use of (Fe VI O 4 2- ) as a green material for use in sustainable treatment processes, especially for soil and water remediation. We reviewed diverse synthesis recipes for ferrates (Fe VI O 4 2- ) and their associated physicochemical properties as oxidants, coagulants, and disinfectants for the elimination of a diverse range of chemical and biological species from water/wastewater samples. A summary of the eco-sustainable performance of ferrate(VI) in water remediation is also provided and the future of ferrate(VI) is discussed in this review. Copyright © 2017 Elsevier Inc. All rights reserved.

Carbon-13 NMR characterization of actinyl(VI) carbonate complexes in aqueous solution

International Nuclear Information System (INIS)

Clark, D.L.; Hobart, D.E.; Palmer, P.D.; Sullivan, J.C.; Stout, B.E.

1992-01-01

The uranyl(VI) carbonate system has been re-examined using 13 C NMR of 99.9% 13 C-enriched U VI O 2 ( 13 CO 3 ) 3 4- in millimolar concentrations. By careful control of carbonate ion concentration, we have confirmed the existence of the trimer, and observed dynamic equilibrium between the monomer and the timer. In addition, the ligand exchange reaction between free and coordinated carbonate on Pu VI O 2 ( 13 CO 3 ) 3 4- and Am VI O 2 ( 13 CO 3 ) 3 4- systems has been examined by variable temperature 13 C NMR line-broadening techniques 13 C NMR line-broadening techniques. A modified Carr-Purcell-Meiboom-Gill NMR pulse sequence was written to allow for experimental determination of ligand exchange parameters for paramagnetic actinide complexes. Preliminary Eyring analysis has provided activation parameters of ΔG double-dagger 295 = 56 kJ/M, ΔH double-dagger = 38 kJ/M, and ΔS double-dagger = -60 J/M-K for the plutonyl triscarbonate system, suggesting an associative transition state for the plutonyl (VI) carbonate complex self-exchange reaction. Experiments for determination of the activation parameters for the americium (VI) carbonate system are in progress

Oral-facial-digital syndrome with mesoaxial polysyndactyly, common AV canal, hirschsprung disease and sacral dysgenesis: Probably a transitional type between II, VI, variant of type VI or a new type

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Rabah M. Shawky

2014-07-01

Full Text Available We report a 4 month old male infant, the first in order of birth of healthy first cousin consanguineous parents who has many typical features of oral-facial-digital syndrome type VI (OFDS VI including hypertelorism, bilateral convergent squint, depressed nasal bridge, and wide upturned nares, low set posteriorly rotated ears, long philtrum, gum hyperplasia with notches of the alveolar borders, high arched palate, and hyperplastic oral frenula. He has mesoaxial and postaxial, polysyndactyly which is the specific feature of OFDS VI, however the cerebellum is normal on MRI brain. He has also some rare congenital anomalies including common atrioventricular canal, hirschsprung disease, and sacral dysgenesis. This patient may have a transitional type between II and VI, a variant of type VI or a new type.

Hvad skal vi med Trump-satire?

DEFF Research Database (Denmark)

Møller, Mette

2017-01-01

Trump-satire er et stort hit, og særligt en lang række satiriske videohilsner til Trump fra lande verden over får folk til at trække på smilebåndet. Men hvorfor er det så sjovt at gøre grin med Trump, og hvad kan vi bruge den politiske humor til?......Trump-satire er et stort hit, og særligt en lang række satiriske videohilsner til Trump fra lande verden over får folk til at trække på smilebåndet. Men hvorfor er det så sjovt at gøre grin med Trump, og hvad kan vi bruge den politiske humor til?...

Analysis of KROTOS KS-2 and KS-4 steam explosion experiments with TEXAS-VI

Energy Technology Data Exchange (ETDEWEB)

Chen, Ronghua, E-mail: rhchen@mail.xjtu.edu.cn [State Key Laboratory of Multiphase Flow in Power Engineering, School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Wang, Jun [Nuclear Engineering and Engineering Physics, College of Engineering, University of Wisconsin Madison, WI 53706 (United States); Su, G.H.; Qiu, Suizheng [State Key Laboratory of Multiphase Flow in Power Engineering, School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049 (China); Corradini, M.L., E-mail: Corradini@engr.wisc.edu [Nuclear Engineering and Engineering Physics, College of Engineering, University of Wisconsin Madison, WI 53706 (United States)

2016-12-01

Highlights: • The KS-2 and KS-4 steam explosion experiments were analyzed by TEXAS-VI. • The coarse mixing status up to the explosion triggering time was well predicted by TEXAS-VI. • The predicted dynamic explosion pressure was in good agreement with the experimental results. - Abstract: TEXAS-VI is a transient, three-field, one-dimensional mechanistic model for the steam explosion phenomena. A fuel solidification model and associated fragmentation criteria of the solidifying particle for both the mixing phase and explosion phase were developed and incorporated into TEXAS-VI to account for solidification. In the present study, TEXAS-VI was used to analyze the KS-2 and KS-4 steam explosion experiments, which were performed in the KROTOS facility as part of the OECD-SERENA-2 program. In the simulation, the KROTOS experimental facility was modeled as Eulerian control volumes based on the facility geometry. The molten corium jet was divided up into a series of LaGrangian master particles equal to the initial jet diameter. Both the mixing phase and the explosion phase of the experiments were simulated by TEXAS-VI. Comparison to test data indicates that the fuel jet kinematics and the vapor volume during the mixing phase were well predicted by TEXAS-VI. The TEXAS-VI prediction of the dynamic explosion pressure at different axial locations in the test was also in good agreement with the experimental results. The maximum pressure of KS-2 and KS-4 predicted by TEXAS-VI were 16.7 MPa and 41.9 MPa, respectively. The KS-4 maximum steam explosion pressure predicted by TEXAS-VI was higher than that of KS-2, which was consistent with experiment observation. The observed differences of the dynamic explosion pressure between the KS-2 and KS-4 experiments were also successfully simulated by TEXAS-VI. This suggests that TEXAS-VI is able to analyze the effect of prototypic melt compositions on the steam explosion phenomena. Additional benchmarking and evaluations are ongoing.

KENO-VI: A Monte Carlo Criticality Program with generalized quadratic geometry

International Nuclear Information System (INIS)

Hollenbach, D.F.; Petrie, L.M.; Landers, N.F.

1993-01-01

This report discusses KENO-VI which is a new version of the KENO monte Carlo Criticality Safety developed at Oak Ridge National Laboratory. The purpose of KENO-VI is to provide a criticality safety code similar to KENO-V.a that possesses a more general and flexible geometry package. KENO-VI constructs and processes geometry data as sets of quadratic equations. A lengthy set of simple, easy-to-use geometric functions, similar to those provided in KENO-V.a., and the ability to build more complex geometric shapes represented by sets of quadratic equations are the heart of the geometry package in KENO-VI. The code's flexibility is increased by allowing intersecting geometry regions, hexagonal as well as cuboidal arrays, and the ability to specify an array boundary that intersects the array

Chemistry of the Colloidal Group II-VI Nanocrystal Synthesis

Energy Technology Data Exchange (ETDEWEB)

Liu, Haitao [Univ. of California, Berkeley, CA (United States)

2007-05-17

In the last two decades, the field of nanoscience andnanotechnology has witnessed tremendous advancement in the synthesis andapplication of group II-VI colloidal nanocrystals. The synthesis based onhigh temperature decomposition of organometallic precursors has becomeone of the most successful methods of making group II-VI colloidalnanocrystals. This methodis first demonstrated by Bawendi and coworkersin 1993 to prepare cadmium chalcogenide colloidal quantum dots and laterextended by others to prepare other group II-VI quantum dots as well asanisotropic shaped colloidal nanocrystals, such as nanorod and tetrapod.This dissertation focuses on the chemistry of this type of nanocrystalsynthesis. The synthesis of group II-VI nanocrystals was studied bycharacterizing the molecular structures of the precursors and productsand following their time evolution in the synthesis. Based on theseresults, a mechanism was proposed to account for the 2 reaction betweenthe precursors that presumably produces monomer for the growth ofnanocrystals. Theoretical study based on density functional theorycalculations revealed the detailed free energy landscape of the precursordecomposition and monomerformation pathway. Based on the proposedreaction mechanism, a new synthetic method was designed that uses wateras a novel reagent to control the diameter and the aspect ratio of CdSeand CdS nanorods.

Kinetics of U(VI) reduction by a dissimilatory Fe(III)-reducing bacterium under non-growth conditions

International Nuclear Information System (INIS)

Truex, M.J.; Peyton, B.M.; Valentine, N.B.; Gorby, Y.A.

1997-01-01

Dissimilatory metal-reducing microorganisms may be useful in processes designed for selective removal of uranium from aqueous streams. These bacteria can use U(VI) as an electron acceptor and thereby reduce soluble U(VI) to insoluble U(IV). While significant research has been devoted to demonstrating and describing the mechanism of dissimilatory metal reduction, the reaction kinetics necessary to apply this for remediation processes have not been adequately defined. In this study, pure culture Shewanella alga strain BrY reduced U(VI) under non-growth conditions in the presence of excess lactate as the electron donor. Initial U(VI) concentrations ranged from 13 to 1,680microM. A maximum specific U(VI) reduction rate of 2.37 micromole-U(VI)/(mg-biomass h) and Monod half-saturation coefficient of 132 microM-U(VI) were calculated from measured U(VI) reduction rates. U(VI) reduction activity was sustained at 60% of this rate for at least 80 h. The initial presence of oxygen at a concentration equal to atmospheric saturation at 22 C delays but does not prevent U(VI) reduction. The rate of U(VI) reduction by BrY is comparable or better than rates reported for other metal reducing species. BrY reduces U(VI) at a rate that is 30% of its Fe(III) reduction rate

Visualisasi Iklan Cetak Mobil VW ”New Beetle” Sebagai Pencitraan Hubungan Manusia dan Teknologi

Directory of Open Access Journals (Sweden)

Hendro Aryanto

2009-01-01

Full Text Available When a new car is launched to the market, sometimes it begins with the appearing of the product advertisement. This happened with VW’s products. In VW Beige ”New Beetle” and VW Black ”New Beetle” print ad versions, they are shown as symbols of beauty and comfort because of their modern technology. VW ”New Beetle” could be the peoples’ choice in many countries with different geographical and cultural backgrounds. In the commodity society, beauty is priceless, for it is supported by the image culture which emphasizes appearance. This point will support belief and loyalty to the brand. Abstract in Bahasa Indonesia: Ketika sebuah mobil baru diluncurkan ke pasar, biasanya diawali dengan pemunculan iklan produk tersebut. Ini yang nampak pada produk VW. Pada iklan cetak versi lipstik VW Beige ”New Beetle” dan VW Black ”New Beetle”, merupakan simbol kecantikan dan kenyamanan karena teknologinya yang modern. VW ”New Beetle” bisa menjadi pilihan orang-orang di negara manapun yang mempunyai geografis yang berbeda-beda tentunya dengan budaya yang berbeda pula. Dalam masyarakat komoditas, kecantikan adalah sangat berharga, karena didukung budaya citra yang mengutamakan penampilan. Hal ini akan mendukung keyakinan dan kesetiaan pada merek tersebut. Kata kunci: iklan cetak, VW Beetle, citra, manusia, teknologi.

Towards a consistent geochemical model for prediction of uranium(VI) removal from groundwater by ferrihydrite

International Nuclear Information System (INIS)

Gustafsson, Jon Petter; Daessman, Ellinor; Baeckstroem, Mattias

2009-01-01

Uranium(VI), which is often elevated in granitoidic groundwaters, is known to adsorb strongly to Fe (hydr)oxides under certain conditions. This process can be used in water treatment to remove U(VI). To develop a consistent geochemical model for U(VI) adsorption to ferrihydrite, batch experiments were performed and previous data sets reviewed to optimize a set of surface complexation constants using the 3-plane CD-MUSIC model. To consider the effect of dissolved organic matter (DOM) on U(VI) speciation, new parameters for the Stockholm Humic Model (SHM) were optimized using previously published data. The model, which was constrained from available X-ray absorption fine structure (EXAFS) spectroscopy evidence, fitted the data well when the surface sites were divided into low- and high-affinity binding sites. Application of the model concept to other published data sets revealed differences in the reactivity of different ferrihydrites towards U(VI). Use of the optimized SHM parameters for U(VI)-DOM complexation showed that this process is important for U(VI) speciation at low pH. However in neutral to alkaline waters with substantial carbonate present, Ca-U-CO 3 complexes predominate. The calibrated geochemical model was used to simulate U(VI) adsorption to ferrihydrite for a hypothetical groundwater in the presence of several competitive ions. The results showed that U(VI) adsorption was strong between pH 5 and 8. Also near the calcite saturation limit, where U(VI) adsorption was weakest according to the model, the adsorption percentage was predicted to be >80%. Hence U(VI) adsorption to ferrihydrite-containing sorbents may be used as a method to bring down U(VI) concentrations to acceptable levels in groundwater

Predicting chromium (VI) adsorption rate in the treatment of liquid ...

African Journals Online (AJOL)

Administrator

The adsorption rate of chromium (VI) on commercial activated carbon during the ... time and initial chromium (VI) ion concentration. .... model, the separation factor r, according to Calvo et al (2001) cited .... Lead (II) and nickel (II) adsorption kinetics .... heavy metal by Talaromyces helicus: a trained fungus for copper and.

Cloning and expression of a Vi mimotope of Salmonella enterica ...

African Journals Online (AJOL)

STORAGESEVER

2009-09-15

Sep 15, 2009 ... A recombinant His-Vi protein of Salmonella enterica serovar Typhi was successfully constructed and cloned into ... mainly through consumption of food or water contami- nated with .... and healthy individuals (double arrows) followed by the detection using recombinant His-Vi protein as the primary antibody ...

Uranium(VI) sorption on iron oxides in Hanford Site sediment: Application of a surface complexation model

International Nuclear Information System (INIS)

Um, Wooyong; Serne, R. Jeffrey; Brown, Christopher F.; Rod, Kenton A.

2008-01-01

Sorption of U(VI) on Hanford fine sand (HFS) with varying Fe-oxide (especially ferrihydrite) contents showed that U(VI) sorption increased with the incremental addition of synthetic ferrihydrite into HFS, consistent with ferrihydrite being one of the most reactive U(VI) sorbents present in natural sediments. Surface complexation model (SCM) calculations for U(VI) sorption, using only U(VI) surface-reaction constants obtained from U(VI) sorption data on freshly synthesized ferrihydrite at different pHs, were similar to the measured U(VI) sorption results on pure synthetic ferrihydrite and on HFS with high contents of ferrihydrite (5 wt%) added. However, the SCM prediction using only U(VI) sorption reactions and constants for synthetic ferrihydrite overestimated U(VI) sorption on the natural HFS or HFS with addition of low amounts of added ferrihydrite (1 wt% added). Over-predicted U(VI) sorption was attributed to reduced reactivity of natural ferrihydrite present in Hanford Site sediments, compared to freshly prepared synthetic ferrihydrite. Even though the SCM general composite (GC) approach is considered to be a semi-quantitative estimation technique for contaminant sorption, which requires systematic experimental data on the sorbent-sorbate system being studied to obtain credible SCM parameters, the general composite SCM model was still found to be a useful technique for describing U(VI) sorption on natural sediments. Based on U(VI) batch sorption results, two simple U(VI) monodentate surface species, SO U O 2 HCO 3 and SO U O 2 OH on ferrihydrite and phyllosillicate in HFS, respectively, can be successfully used to describe U(VI) sorption onto Hanford Site sediment contacting varying geochemical solutions

Ferrate(VI) as a greener oxidant: Electrochemical generation and treatment of phenol.

Science.gov (United States)

Sun, Xuhui; Zhang, Qi; Liang, He; Ying, Li; Xiangxu, Meng; Sharma, Virender K

2016-12-05

Ferrate(VI) (Fe(VI)O4(2-), Fe(VI)) is a greener oxidant in the treatment of drinking water and wastewater. The electrochemical synthesis of Fe(VI) may be considered environmentally friendly because it involves one-step process to convert Fe(0) to Fe(VI) without using harmful chemicals. Electrolysis was performed by using a sponge iron as an anode in NaOH solution at different ionic strengths. The cyclic voltammetric (CV) curves showed that the sponge iron had higher electrical activity than the grey cast iron. The optimum current density was 0.054mAcm(-2) in 10M NaOH solution, which is much lower than the electrolyte concentrations used in other electrode materials. A comparison of current efficiency and energy consumption was conducted and is briefly discussed. The generated ferrate solution was applied to degrade phenol in water at two levels (2mgL(-1) and 5mgL(-1)). The maximum removal efficiency was ∼70% and the optimum pH for phenol treatment was 9.0. Experiments on phenol removal using conventional coagulants (ferric chloride (FeCl3) and polyaluminium chloride (PAC)) were performed independently to demonstrate that removal of phenol by Fe(VI) occurred mainly by oxidative transformation. A combination of Fe(VI) and coagulant may be advantageous in enhancing removal efficiency, adjusting pH, and facilitating flocculation. Copyright © 2015 Elsevier B.V. All rights reserved.

The O VI Mystery: Mismatch between X-Ray and UV Column Densities

Science.gov (United States)

Mathur, S.; Nicastro, F.; Gupta, A.; Krongold, Y.; McLaughlin, B. M.; Brickhouse, N.; Pradhan, A.

2017-12-01

The UV spectra of Galactic and extragalactic sightlines often show O VI absorption lines at a range of redshifts, and from a variety of sources from the Galactic circumgalactic medium to active galactic nuclei (AGN) outflows. Inner shell O VI absorption is also observed in X-ray spectra (at λ =22.03 Å), but the column density inferred from the X-ray line was consistently larger than that from the UV line. Here we present a solution to this discrepancy for the z = 0 systems. The O II Kβ line {}4{S}0\\to {(}3D)3{p}4P at 562.40 eV (≡22.04 Å) is blended with the O VI Kα line in X-ray spectra. We estimate the strength of this O II line in two different ways, and show that in most cases the O II line accounts for the entire blended line. The small amount of O VI equivalent width present in some cases has column density entirely consistent with the UV value. This solution to the O VI discrepancy, however, does not apply to high column-density systems like AGN outflows. We discuss other possible causes to explain their UV/X-ray mismatch. The O VI and O II lines will be resolved by gratings on board the proposed mission Arcus and the concept mission Lynx, and would allow the detection of weak O VI lines not just at z = 0, but also at higher redshift.

Sediment studies of the biological factors controlling the reduction of U(VI)

International Nuclear Information System (INIS)

Lovley, Derek R.

2004-01-01

Studies were conducted primarily with sediments, both in laboratory incubations and in a field experiment, with supporting studies with pure cultures. To our knowledge the sediment studies were the first on microbial U(VI) reduction in actual uranium-contaminated subsurface sediments, under conditions that mimic those found in situ. Important findings included: (1) U(VI) reduction is a biotic process in subsurface sediments. (2) U(VI) reduction can be stimulated most effectively with the addition of acetate. Although it had been speculated that microbial U(VI) reduction might be capable of this type of environmental remediation ever since the discovery of microbial U(VI) reduction, this had not been previously demonstrated under environmentally relevant conditions. (3) U(VI) is reduced concurrently with Fe(III) and prior to sulfate reduction. U(VI) and Fe(III) reduction proceeded concurrently, accompanied by a dramatic enrichment in organisms in the Geobacteraceae. Sulfate-reducing microorganisms do not appear to be important components of the microbial community reducing U(VI) in these subsurface sediments. (4) Nitrate has important influences on U(VI) reduction. Nitrate inhibits the reduction of metals until nitrate is depleted. Fe(III)-reducing microorganisms such as Geobacter metallireducens and Desulfitobacterium species can oxidize Fe(II) with the reduction of nitrate which is an important consideration because our previous studies have demonstrated that freshly precipitated Fe(III) oxides can reoxidize U(IV) to U(VI). The discovery that G. metallireducens can ''run backwards'' and oxidize U(IV) when nitrate is present reveals another mechanism preventing precipitation of U(IV) in the presence of nitrate as well as potential novel strategy for removing uranium from the subsurface after a site has been remediated. (5) Importance of understanding Fe(III) forms available for microbial reduction. Fe(III) is orders of magnitude more abundant than U(VI) as an

Chromium VI and stomach cancer: a meta-analysis of the current epidemiological evidence.

Science.gov (United States)

Welling, Roberta; Beaumont, James J; Petersen, Scott J; Alexeeff, George V; Steinmaus, Craig

2015-02-01

Chromium VI (hexavalent chromium, Cr(VI)) is an established cause of lung cancer, but its association with gastrointestinal cancer is less clear. The goal of this study was to examine whether the current human epidemiological research on occupationally inhaled Cr(VI) supports the hypothesis that Cr(VI) is associated with human stomach cancer. Following a thorough literature search and review of individual studies, we used meta-analysis to summarise the current epidemiological literature on inhaled Cr(VI) and stomach cancer, explore major sources of heterogeneity, and assess other elements of causal inference. We identified 56 cohort and case-control studies and 74 individual relative risk (RR) estimates on stomach cancer and Cr(VI) exposure or work in an occupation associated with high Cr(VI) exposure including chromium production, chrome plating, leather work and work with Portland cement. The summary RR for all studies combined was 1.27 (95% CI 1.18 to 1.38). In analyses limited to only those studies identifying increased risks of lung cancer, the summary RR for stomach cancer was higher (RR=1.41, 95% CI 1.18 to 1.69). Overall, these results suggest that Cr(VI) is a stomach carcinogen in humans, which is consistent with the tumour results reported in rodent studies. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

GeoViQua: quality-aware geospatial data discovery and evaluation

Science.gov (United States)

Bigagli, L.; Papeschi, F.; Mazzetti, P.; Nativi, S.

2012-04-01

GeoViQua (QUAlity aware VIsualization for the Global Earth Observation System of Systems) is a recently started FP7 project aiming at complementing the Global Earth Observation System of Systems (GEOSS) with rigorous data quality specifications and quality-aware capabilities, in order to improve reliability in scientific studies and policy decision-making. GeoViQua main scientific and technical objective is to enhance the GEOSS Common Infrastructure (GCI) providing the user community with innovative quality-aware search and evaluation tools, which will be integrated in the GEO-Portal, as well as made available to other end-user interfaces. To this end, GeoViQua will promote the extension of the current standard metadata for geographic information with accurate and expressive quality indicators, also contributing to the definition of a quality label (GEOLabel). GeoViQua proposed solutions will be assessed in several pilot case studies covering the whole Earth Observation chain, from remote sensing acquisition to data processing, to applications in the main GEOSS Societal Benefit Areas. This work presents the preliminary results of GeoViQua Work Package 4 "Enhanced geo-search tools" (WP4), started in January 2012. Its major anticipated technical innovations are search and evaluation tools that communicate and exploit data quality information from the GCI. In particular, GeoViQua will investigate a graphical search interface featuring a coherent and meaningful aggregation of statistics and metadata summaries (e.g. in the form of tables, charts), thus enabling end users to leverage quality constraints for data discovery and evaluation. Preparatory work on WP4 requirements indicated that users need the "best" data for their purpose, implying a high degree of subjectivity in judgment. This suggests that the GeoViQua system should exploit a combination of provider-generated metadata (objective indicators such as summary statistics), system-generated metadata (contextual

Immobilization of Cr(Vi) as a contaminant from soil by iron compounds; Inmovilizacion de Cr(VI) como contaminante del suelo por compuestos de hierro

Energy Technology Data Exchange (ETDEWEB)

Marin A, M. de J.; Romero G, E. T. [ININ, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico); Reyes G, L. R. [Universidad Autonoma del Estado de Hidalgo, Centro de Investigacion en Ciencias de la Tierra, Carretera Pachuca-Tulancingo Km. 4.5, Pachuca 42184, Hidalgo (Mexico)], e-mail: elizabeth.romero@inin.gob.mx

2008-07-01

The objective of this research was to determine the physicochemical and surface properties of Fe{sup 0} and FeS to select the appropriate radioactive material for use in the design of artificial barriers or walls and remove Cr (Vi). The physicochemical characterization was carried out of iron: Fe{sup 0} and FeS, using scanning electron microscopy of high vacuum, X-ray diffraction and thermal gravimetric analysis techniques. As for the characterization of the surface, was used to determine the surface area, point of zero charge, density of active sites and kinetics of moisture. We obtained a solution of Cr (Vi) by elution of deionized water on the pollution land of Buenavista, Guanajuato. The concentration of Cr (Vi) from a stock solution was 55.56 mg / L determined by UV-Vis spectrophotometry. Stripping or maximum immobilization of Cr (Vi) with Fe{sup 0} (material chosen by their physicochemical and surface properties) was 68.25% using Fe{sup 0}, at a concentration less than 0.1, ph equal to 3 and a contact time of 24 hours. (Author)

Ferric chloride modified zeolite in wastewater on Cr (VI) adsorption characteristics

Science.gov (United States)

Wu, Xiaoqing; Zhang, Kang; Chen, Wen; Zhang, Hua

2018-03-01

Zeolite was modified by ferric chloride(Fe-Z) removal Cr (VI) ion from wastewater. The results showed that the effect of Cr(VI) adsorption on modified zeolite depended significantly on pH. It is favorable for the adsorption of Cr(VI) in acid condition. The Langmuir isotherm model has high fitting accuracy with experimental data, demonstrated that is monolayer adsorption and chemical adsorption.The pseudo-second-order equation provided the best correlation to the data. The model can describe the adsorption reaction process well.

29 CFR 1910.1026 - Chromium (VI).

Science.gov (United States)

2010-07-01

... allows employees to consume food or beverages at a worksite where chromium (VI) is present, the employer... effect on productivity. 2. Plating Bath Surface Tension Management and Fume Suppression • Lower surface...

Validación de un ELISA tipo inhibición para cuantificar polisacárido Vi en la vacuna antitifoídica cubana vax-TyVi

Directory of Open Access Journals (Sweden)

Esther María Fajardo

2006-08-01

Full Text Available Se describe la validación de un ELISA tipo inhibición, reportado por primera vez en la literatura científica para cuantificar un antígeno vacunal: el polisacárido Vi de Salmonella Typhi, para ser empleado en el control de la calidad de la vacuna antitifoídica cubana vax- TyViâ. El ensayo consta de seis pasos: 1 Recubrimiento de placa de reacción con poli-L-lisina y posteriormente polisacárido Vi; 2 Bloqueo con leche descremada; 3 Inhibición o neutralización en tubos de suero anti-Vi de conejo, respectivamente, con polisacárido Vi de Curva de Calibración (concentraciones desde 1–32 μg/mL, control positivo y muestras de vacuna (3 diluciones; 4 Neutralización de anticuerpos anti-Vi libres, presentes en las mezclas anteriores, por el Polisacárido de Recubrimiento; 5 Reconocimiento de anticuerpos anti-Vi unidos a la placa (conjugado anti-IgG de conejo-fosfatasa alcalina y 6 Revelado por reacción enzima-sustrato. Los parámetros de validación estudiados y sus resultados fueron: 1 Precisión, expresada como coeficiente de variación a tres niveles de concentración de polisacárido, comprendidos en el rango de su especificación (35, 50 y 70 μg/mL y evaluada en términos de repetibilidad; precisión intraensayos (cuatro analistas y reproducibilidad (seis analistas: £ 20%; 2 Linealidad (100*R2: 99,68 %; 3 Límite de detección: 0,5 μg/mL; 4 Exactitud (recuperación para las tres diluciones de la muestra: entre 100 y 118%, y 5 Robustez: no influye 1,5 h de bloqueo (p = 0,52 ni ± 5 min para leer placa (p = 0,56; influye grandemente la calidad del agua (p = 0,026, a favor del agua para inyección. El ensayo es adecuado para los fines propuestos y es una medida de la inmunogenicidad in vitro del polisacárido Vi.

Ex-situ bioremediation of U(VI from contaminated mine water using Acidithiobacillus ferrooxidans strains

Directory of Open Access Journals (Sweden)

Maria eRomero-Gonzalez

2016-05-01

Full Text Available The ex-situ bioremoval of U(VI from contaminated water using Acidithiobacillus ferrooxidans strain 8455 and 13538 was studied under a range of pH and uranium concentrations. The effect of pH on the growth of bacteria was evaluated across the range 1.5 – 4.5 pH units. The respiration rate of At. ferrooxidans at different U(VI concentrations was quantified as a measure of the rate of metabolic activity over time using an oxygen electrode. The biosorption process was quantified using a uranyl nitrate solution, U-spiked growth media and U-contaminated mine water. The results showed that both strains of At. ferrooxidans are able to remove U(VI from solution at pH 2.5 – 4.5, exhibiting a buffering capacity at pH 3.5. The respiration rate of the micro-organism was affected at U(VI concentration of 30 mg L-1. The kinetics of the sorption fitted a pseudo-first order equation, and depended on the concentration of U(VI. The KD obtained from the biosorption experiments indicated that strain 8455 is more efficient for the removal of U(VI. A bioreactor designed to treat a solution of 100 mg U(VI L-1 removed at least 50% of the U(VI in water. The study demonstrated that At. ferrooxidans can be used for the ex-situ bioremediation of U(VI contaminated mine water.

Polyaniline (PANI) modified bentonite by plasma technique for U(VI) removal from aqueous solution

International Nuclear Information System (INIS)

Liu, Xinghao; Cheng, Cheng; Xiao, Chengjian; Shao, Dadong; Xu, Zimu; Wang, Jiaquan; Hu, Shuheng; Li, Xiaolong; Wang, Weijuan

2017-01-01

Highlights: • PANI/bentonie can be synthesized by simple plasma technique. • PANI/bentonie has an excellent adsorption capacity for trace uranium in solution. • U(VI) adsorption on PANI/bentonite is a spontaneous and endothermic process. - Abstract: Polyaniline (PANI) modified bentonite (PANI/bentonie) was synthesized by plasma induced polymerization of aniline on bentonite surface, and applied to uptake of uranium(VI) ions from aqueous solution. The as-synthesized PANI/bentonie was characterized by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), thermal gravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). Batch adsorption technique was utilized to investigate the adsorption of U(VI) on bentonite and PANI/bentonite. The adsorption of U(VI) (10 mg/L) on PANI/bentonite surface is fairly depend on solution pH, ionic strength, and temperature in solution. The modified PANI on PANI/bentonite surface significantly enhances its adsorption capability for U(VI). The presence of humic acid (HA) can sound enhance U(VI) adsorption on PANI/bentonite at pH 6.5. According to the thermodynamic parameters, the adsorption of U(VI) on PANI/bentonite surface is a spontaneous and endothermic process. The results highlight the application of PANI/bentonite composites as candidate material for the uptake of trace U(VI) from aqueous solution.

Spectroscopic Confirmation of Uranium (VI)-Carbonato Adsorption Complexes on Hematite

International Nuclear Information System (INIS)

Bargar, John R

1999-01-01

Evaluating societal risks posed by uranium contamination from waste management facilities, mining sites, and heavy industry requires knowledge about uranium transport in groundwater, often the most significant pathway of exposure to humans. It has been proposed that uranium mobility in aquifers may be controlled by adsorption of U(VI)-carbonato complexes on oxide minerals. The existence of such complexes has not been demonstrated, and little is known about their compositions and reaction stoichiometries. We have used Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) and Extended X-ray Absorption Fine Structure (EXAFS) spectroscopies to probe the existence, structures, and compositions of FeO surface -U(VI)-carbonato complexes on hematite throughout the pH range of uranyl uptake under conditions relevant to aquifers. U(VI)-carbonato complexes were found to be the predominant adsorbed U(VI) species at all pH values examined, a much wider pH range than previously postulated based on analogy to aqueous U(VI)-carbonato complexes, which are trace constituents at pH < 6. This result indicates the inadequacy of the common modeling assumption that the compositions and predominance of adsorbed species can be inferred from aqueous species. By extension, adsorbed carbonato complexes may be of major importance to the groundwater transport of similar actinide contaminants such as neptunium and plutonium

Experiments indicating a second hydrogen ordered phase of ice VI.

Science.gov (United States)

Gasser, Tobias M; Thoeny, Alexander V; Plaga, Lucie J; Köster, Karsten W; Etter, Martin; Böhmer, Roland; Loerting, Thomas

2018-05-14

In the last twelve years five new ice phases were experimentally prepared. Two of them are empty clathrate hydrates and three of them represent hydrogen ordered counterparts of previously known disordered ice phases. Here, we report on hydrogen ordering in ice VI samples produced by cooling at pressures up to 2.00 GPa. Based on results from calorimetry, dielectric relaxation spectroscopy, Raman spectroscopy, and powder X-ray diffraction the existence of a second hydrogen ordered polymorph related to ice VI is suggested. Powder X-ray data show the oxygen network to be the one of ice VI. For the 1.80 GPa sample the activation energy from dielectric spectroscopy is 45 kJ mol -1 , which is much larger than for the known hydrogen ordered proxy of ice VI, ice XV. Raman spectroscopy indicates the 1.80 GPa sample to be more ordered than ice XV. It is further distinct from ice XV in that it experiences hydrogen disordering above ≈103 K which is 26 K below the ice XV to ice VI disordering transition. Consequently, below 103 K it is thermodynamically more stable than ice XV, adding a stability region to the phase diagram of water. For the time being we suggest to call this new phase ice β-XV and to relabel it ice XVIII once its crystal structure is known.

Cr(VI) reduction in wastewater using a bimetallic galvanic reactor

International Nuclear Information System (INIS)

Lugo-Lugo, Violeta; Barrera-Diaz, Carlos; Bilyeu, Bryan; Balderas-Hernandez, Patricia; Urena-Nunez, Fernando; Sanchez-Mendieta, Victor

2010-01-01

The electrochemical reduction of Cr(VI)-Cr(III) in wastewater by iron and copper-iron bimetallic plates was evaluated and optimized. Iron has been used as a reducing agent, but in this work a copper-iron galvanic system in the form of bimetallic plates is applied to reducing hexavalent chromium. The optimal pH (2) and ratio of copper to iron surface areas (3.5:1) were determined in batch studies, achieving a 100% reduction in about 25 min. The Cr(VI) reduction kinetics for the bimetallic system fit a first order mechanism with a correlation of 0.9935. Thermodynamic analysis shows that the Cr(VI) reduction is possible at any pH value. However, at pH values above 3.0 for iron and 5.5 for chromium insoluble species appear, indicating that the reaction will be hindered. Continuous column studies indicate that the bimetallic copper-iron galvanic system has a reduction capacity of 9.5890 mg Cr(VI) cm -2 iron, whereas iron alone only has a capacity of 0.1269 mg Cr(VI) cm -2 . The bimetallic copper-iron galvanic system is much more effective in reducing hexavalent chromium than iron alone. The exhausted plates were analyzed by SEM, EDS, and XRD to determine the mechanism and the surface effects, especially surface fouling.

Validation of the Preverbal Visual Assessment (PreViAs) questionnaire.

Science.gov (United States)

García-Ormaechea, Inés; González, Inmaculada; Duplá, María; Andres, Eva; Pueyo, Victoria

2014-10-01

Visual cognitive integrative functions need to be evaluated by a behavioral assessment, which requires an experienced evaluator. The Preverbal Visual Assessment (PreViAs) questionnaire was designed to evaluate these functions, both in general pediatric population or in children with high risk of visual cognitive problems, through primary caregivers' answers. We aimed to validate the PreViAs questionnaire by comparing caregiver reports with results from a comprehensive clinical protocol. A total of 220 infants (visual development, as determined by the clinical protocol. Their primary caregivers completed the PreViAs questionnaire, which consists of 30 questions related to one or more visual domains: visual attention, visual communication, visual-motor coordination, and visual processing. Questionnaire answers were compared with results of behavioral assessments performed by three pediatric ophthalmologists. Results of the clinical protocol classified 128 infants as having normal visual maturation, and 92 as having abnormal visual maturation. The specificity of PreViAs questionnaire was >80%, and sensitivity was 64%-79%. More than 80% of the infants were correctly classified, and test-retest reliability exceeded 0.9 for all domains. The PreViAs questionnaire is useful to detect abnormal visual maturation in infants from birth to 24months of age. It improves the anamnesis process in infants at risk of visual dysfunctions. Copyright © 2014. Published by Elsevier Ireland Ltd.

[Adsorptive Stabilization of Soil Cr (VI) Using HDTMA Modified Montmorillonite].

Science.gov (United States)

2016-03-15

A series of organo-montomorillonites were prepared using Na-montomorillonite and hexadecyl trimethyl ammonium bromide (HDTMA). The organo-montomorillonites were then investigated for the remediation of Cr(VI) contaminated soils. FT-IR, XRD, SEM and N2 -BET, CEC, Zeta potential measurement were conducted to understand the structural changes of montmorillonites as different amounts of HDTMAs were added as modifier. The characterization results indicated that the clay interlayer spacing distance increased from 1. 25 nm to 2. 13 nm, the clay surface roughness decreased, the clay surface area reduced from 38.91 m² · g⁻¹ to 0.42 m² · g⁻¹, the clay exchangeable cation amount reduced from 62 cmol · kg⁻¹ to 9.9 cmol · kg⁻¹ and the clay surface charge changed from -29.1 mV to 5.59 mV as the dosage of HDTMA in montmorillonite was increased. The TCLP (toxicity characteristic leaching procedure) was used to evaluate the leachate toxicity of Cr(VI). The effects of the initial soil Cr(VI) concentration, montmorillonites dosage, reaction time and HDTMA modification amount were investigated, respectively. The results revealed that modification of montmorillonites would manifest an attenuated physical adsorptive effect and an enhanced electrostatic adsorptive effect on Cr(VI), suggesting electrostatic effect was the major force that resulted in improved Cr(VI) adsorption onto HDTMA modified montmorillonites.

Polyaniline (PANI) modified bentonite by plasma technique for U(VI) removal from aqueous solution

Science.gov (United States)

Liu, Xinghao; Cheng, Cheng; Xiao, Chengjian; Shao, Dadong; Xu, Zimu; Wang, Jiaquan; Hu, Shuheng; Li, Xiaolong; Wang, Weijuan

2017-07-01

Polyaniline (PANI) modified bentonite (PANI/bentonie) was synthesized by plasma induced polymerization of aniline on bentonite surface, and applied to uptake of uranium(VI) ions from aqueous solution. The as-synthesized PANI/bentonie was characterized by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), thermal gravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS). Batch adsorption technique was utilized to investigate the adsorption of U(VI) on bentonite and PANI/bentonite. The adsorption of U(VI) (10 mg/L) on PANI/bentonite surface is fairly depend on solution pH, ionic strength, and temperature in solution. The modified PANI on PANI/bentonite surface significantly enhances its adsorption capability for U(VI). The presence of humic acid (HA) can sound enhance U(VI) adsorption on PANI/bentonite at pH 6.5. According to the thermodynamic parameters, the adsorption of U(VI) on PANI/bentonite surface is a spontaneous and endothermic process. The results highlight the application of PANI/bentonite composites as candidate material for the uptake of trace U(VI) from aqueous solution.

Adsorption equilibrium studies of uranium (VI) onto cross-linked chitosan-citric acid

International Nuclear Information System (INIS)

Ho Thi Yeu Ly; Nguyen Van Suc; Vo Quang Mai; Nguyen Mong Sinh

2011-01-01

Investigation of U(VI) adsorption by the cross- linked chitosan with citric acid was conduced by bath method. Effect of parameters such as pH, contact time, adsorbent dosage and other metal cations was determined. The maximum adsorption capacity of U(VI) at pH 4 was found to be 71.43 mg U(VI) / g cross-linked chitosan - citric acid after 300 min of contact time. The Langmuir and Freundlich isotherm models were used to describe adsorption equilibrium. The correction values, R 2 of two models were found to be 0.991 and 0.997, respectively. Therefore, it could be concluded that the adsorption equilibrium for U(VI) was followed the Langmuir and the Freundlich isotherm models. (author)

Removal of Cr(VI) from Aqueous Environments Using Micelle-Clay Adsorption

Science.gov (United States)

Qurie, Mohannad; Khamis, Mustafa; Manassra, Adnan; Ayyad, Ibrahim; Nir, Shlomo; Scrano, Laura; Bufo, Sabino A.; Karaman, Rafik

2013-01-01

Removal of Cr(VI) from aqueous solutions under different conditions was investigated using either clay (montmorillonite) or micelle-clay complex, the last obtained by adsorbing critical micelle concentration of octadecyltrimethylammonium ions onto montmorillonite. Batch experiments showed the effects of contact time, adsorbent dosage, and pH on the removal efficiency of Cr(VI) from aqueous solutions. Langmuir adsorption isotherm fitted the experimental data giving significant results. Filtration experiments using columns filled with micelle-clay complex mixed with sand were performed to assess Cr(VI) removal efficiency under continuous flow at different pH values. The micelle-clay complex used in this study was capable of removing Cr(VI) from aqueous solutions without any prior acidification of the sample. Results demonstrated that the removal effectiveness reached nearly 100% when using optimal conditions for both batch and continuous flow techniques. PMID:24222757

Predicting chromium (VI) adsorption rate in the treatment of liquid ...

African Journals Online (AJOL)

The adsorption rate of chromium (VI) on commercial activated carbon during the treatment of the flocculation effluent of liquid-phase oil-based drill-cuttings has been investigated in terms of contact time and initial chromium (VI) ion concentration. Homogenizing 1 g of the activated carbon with 100 ml of the flocculation ...

Effect of selected ligands on the U(VI) immobilization by zerovalent iron

International Nuclear Information System (INIS)

Noubactep, C.

2006-01-01

The effect of Cl - , CO 3 2- , EDTA, NO 2 - , NO 3 - , PO 4 3- , SO 4 2- , and humic substances (HS) on the U(VI) co-precipitation from aqueous solutions by zerovalent iron (ZVI) was investigated in the neutral pH range.Batch experiments without shaking were conducted for 14 days mostly with five different ZVI materials (15 g/l), selected ligands (10mM) and an U(VI) solution (20 mg/l, 0.084mM). Apart from Cl - , all tested ligands induced a decrease of U(VI) coprecipitation. This decrease is attributed to the surface adsorption and complexation of the ligands at the reactive sites on the surface of ZVI and their corrosion products. The decrease of U(VI) removal was not uniform with the five ZVI materials. Generally, groundwater with elevated EDTA concentration could not be remediated with the ZVI barrier technology. The response of the system on the pre-treating by two ZVI materials in 250mM HCl indicated that in situ generated corrosion products favor an irreversible U(VI) uptake. Thus for the long term performance of ZVI barrier, the iron dissolution should continue in such a way that fresh iron oxide be always available for U(VI) coprecipitation. (author)

Influence of U(VI) on the metabolism of plant cells studied by microcalorimetry and TRLFS

Energy Technology Data Exchange (ETDEWEB)

Sachs, Susanne; Geipel, Gerhard [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biogeochemistry; Fahmy, Karim; Oertel, Jana [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biophysics; Bok, Frank [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes

2017-06-01

Uranium(VI) shows a concentration-dependent influence on the metabolic activity of plant cells. With increasing U(VI) concentration, the predominant U(VI) species in medium R{sub red} changes from UO{sub 2}HPO{sub 4}(s) to (UO{sub 2}){sub 3}(OH){sub 5}{sup +}, which may affect the bioavailability of U(VI).

Adsorption of chromium(VI) on pomace-An olive oil industry waste: Batch and column studies

International Nuclear Information System (INIS)

Malkoc, Emine; Nuhoglu, Yasar; Dundar, Murat

2006-01-01

The waste pomace of olive oil factory (WPOOF) was tested for its ability to remove chromium(VI) from aqueous solution by batch and column experiments. Various thermodynamic parameters, such as ΔG o , ΔH o and ΔS o have been calculated. The thermodynamics of chromium(VI) ion onto WPOOF system indicates spontaneous and endothermic nature of the process. The ability of WPOOF to adsorb chromium(VI) in a fixed bed column was investigated, as well. The effect of operating parameters such as flow rate and inlet metal ion concentration on the sorption characteristics of WPOOF was investigated. The longest breakthrough time and maximum of Cr(VI) adsorption is obtained at pH 2.0. The total adsorbed quantities, equilibrium uptakes and total removal percents of chromium(VI) related to the effluent volumes were determined by evaluating the breakthrough curves obtained at different flow rates and different inlet chromium(VI) concentrations for adsorbent. The data confirmed that the total amount of sorbed chromium(VI) and equilibrium chromium(VI) uptake decreased with increasing flow rate and increased with increasing inlet chromium(VI) concentration. The Adams-Bohart model were used to analyze the experimental data and the model parameters were evaluated

Remediation of Cr(VI) contaminated soil using long-duration sodium thiosulfate supported by micro–nano networks

International Nuclear Information System (INIS)

He, Lulu; Wang, Min; Zhang, Guilong; Qiu, Guannan; Cai, Dongqing; Wu, Zhengyan; Zhang, Xin

2015-01-01

Highlights: • This work aims to develop a long-duration remediation agent (LRA). • LRA was obtained using Na 2 S 2 O 3 supported by attapulgite (ATP) micro–nano networks. • ATP micro–nano networks was induced by high-energy electron beam irradiation. • LRA can effectively control the migration of Cr(VI) and reducing Cr(VI) to Cr(III). • LRA displayed high performance on the remediation of heavy metal contaminated soil. - Abstract: In this work, a long-duration remediation agent (LRA) on hexavalent chromium (Cr(VI)) was developed using sodium thiosulfate (ST) supported by attapulgite (ATP) micro–nano networks induced through high-energy electron beam (HEEB) irradiation. The ATP networks could effectively reduce the leaching amount of Cr(VI) in soil. More importantly, the ATP networks could significantly control the leaching behavior of ST, and then prolong the duration and increase the reduction efficiency of ST on Cr(VI). As a result, LRA displayed high performance on controlling the migration of Cr(VI) and reducing Cr(VI) to Cr(III). Additionally, pot experiment indicated that LRA could effectively decrease the absorbed amount of Cr(VI) in corn, and reduce the inhibition effect of Cr(VI) on the growth of corn. Therefore, this work could provide a facile approach to remediate the Cr(VI)-contaminated soil and lower the harmful effect of Cr(VI) on crop

Remediation of Cr(VI) contaminated soil using long-duration sodium thiosulfate supported by micro–nano networks

Energy Technology Data Exchange (ETDEWEB)

He, Lulu [School of Life Sciences, Anhui Agricultural University, Hefei 230036 (China); Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Wang, Min; Zhang, Guilong [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Qiu, Guannan [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Cai, Dongqing, E-mail: dqcai@ipp.ac.cn [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Wu, Zhengyan, E-mail: zywu@ipp.ac.cn [Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences and Anhui Province, Hefei, Anhui 230031 (China); Bioenergy Forest Research Center of State Forestry Administration, Hefei 230031 (China); Zhang, Xin, E-mail: xinzhang@ahau.edu.cn [School of Life Sciences, Anhui Agricultural University, Hefei 230036 (China)

2015-08-30

Highlights: • This work aims to develop a long-duration remediation agent (LRA). • LRA was obtained using Na{sub 2}S{sub 2}O{sub 3} supported by attapulgite (ATP) micro–nano networks. • ATP micro–nano networks was induced by high-energy electron beam irradiation. • LRA can effectively control the migration of Cr(VI) and reducing Cr(VI) to Cr(III). • LRA displayed high performance on the remediation of heavy metal contaminated soil. - Abstract: In this work, a long-duration remediation agent (LRA) on hexavalent chromium (Cr(VI)) was developed using sodium thiosulfate (ST) supported by attapulgite (ATP) micro–nano networks induced through high-energy electron beam (HEEB) irradiation. The ATP networks could effectively reduce the leaching amount of Cr(VI) in soil. More importantly, the ATP networks could significantly control the leaching behavior of ST, and then prolong the duration and increase the reduction efficiency of ST on Cr(VI). As a result, LRA displayed high performance on controlling the migration of Cr(VI) and reducing Cr(VI) to Cr(III). Additionally, pot experiment indicated that LRA could effectively decrease the absorbed amount of Cr(VI) in corn, and reduce the inhibition effect of Cr(VI) on the growth of corn. Therefore, this work could provide a facile approach to remediate the Cr(VI)-contaminated soil and lower the harmful effect of Cr(VI) on crop.

Strain/size analysis in ternary compounds AgIn{sub 5} VI{sub 8} (Vi = S, Se, Te) by X-ray diffraction; Analisis de tension/tamano en compuestos ternarios AgIn{sub 5} VI{sub 8} (VI = S, Se, Te) mediante difraccion de rayos X

Energy Technology Data Exchange (ETDEWEB)

Fermin, J. R.; Salcedo, D. Y.; Durante R, C.; Castro, J. A. [Universidad del Zulia, Facultad Experimental de Ciencias, Departamento de Fisica, Maracaibo, Zulia (Venezuela, Bolivarian Republic of)

2017-11-01

In this work, we have study the microstructural properties of the ternary compounds AgIn{sub 5} VI{sub 8} (Vi = S, Se, Te) by X-ray diffraction technique (XRD). The linewidth of the XRD profile is measured as function of the diffraction angle. Structural parameters such as, average grain size, micro strains, and crystalline dislocation density, are obtained on the framework of a strain/size analysis based on the modified Scherrer equation for Gaussian profiles. The crystalline dislocation arrange according to a Gaussian distribution function, indicating that these dislocations are randomly distributed within the grains. (Author)

Modification of zirconium diphosphate with salicylic acid and its effect on the uranium (Vi) sorption; Modificacion del difosfato de circonio con acido salicilico y su efecto sobre la sorcion de uranio (VI)

Energy Technology Data Exchange (ETDEWEB)

Almazan T, M. G.; Garcia G, N. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Simoni, E., E-mail: guadalupe.almazan@inin.gob.mx [Universidad Paris Sud, Instituto de Fisica Nuclear, Georges Clemenceau No. 15, Orsay (France)

2014-10-15

The surface of zirconium diphosphate (ZrP{sub 2}O{sub 7}) was modified with salicylic acid and its effect was evaluated on the uranium (Vi) sorption. The modified surface of the material was analyzed with different analytical techniques among which are included the atomic force microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy. This analysis allowed showing that the salicylic acid is being held on the surface of the zirconium diphosphate. The reactivity of modified zirconium diphosphate compared with uranium (Vi) was investigated using the classical method of batch sorption. The analysis of sorption isotherms shows that the salicylic acid has an important effect in the uranium (Vi) sorption. According to the study conducted, the interaction among the uranium (Vi) and the surface of zirconium diphosphate modified with the salicylic acid most likely leads to the complexes formation of binary (U(Vi)/ZrP{sub 2}O{sub 7}) and ternary (U(Vi)/salicylate/ZrP{sub 2}O{sub 7}) surface. (Author)

Delineation and Diagnostic Criteria of Oral-Facial-Digital Syndrome Type VI

NARCIS (Netherlands)

Poretti, Andrea; Vitiello, Giuseppina; Hennekam, Raoul C. M.; Arrigoni, Filippo; Bertini, Enrico; Borgatti, Renato; Brancati, Francesco; D'Arrigo, Stefano; Faravelli, Francesca; Giordano, Lucio; Huisman, Thierry A. G. M.; Iannicelli, Miriam; Kluger, Gerhard; Kyllerman, Marten; Landgren, Magnus; Lees, Melissa M.; Pinelli, Lorenzo; Romaniello, Romina; Scheer, Ianina; Schwarz, Christoph E.; Spiegel, Ronen; Tibussek, Daniel; Valente, Enza Maria; Boltshauser, Eugen

2012-01-01

Oral-Facial-Digital Syndrome type VI (OFD VI) represents a rare phenotypic subtype of Joubert syndrome and related disorders (JSRD). In the original report polydactyly, oral findings, intellectual disability, and absence of the cerebellar vermis at post-mortem characterized the syndrome.

Plutonium(IV) peroxide formation in nitric medium and kinetics Pu(VI) reduction by hydrogen peroxide

International Nuclear Information System (INIS)

Maillard, C.; Adnet, J.M.

2001-01-01

Reduction of plutonium (VI) to Pu(IV) with hydrogen peroxide is a step in industrial processes used to purify plutonium nitrate solutions. This operation must be carefully controlled, in order to avoid any formation of the Pu(IV) peroxide green precipitate and to obtain exclusively Pu(IV). This led us to study the acidity and Pu and H 2 O 2 concentrations influences on the precipitate appearance and to perform a Pu(VI) reduction kinetic study on a wide range of acidities ([HNO 3 ]: 0.5 to 8 M), plutonium concentrations ([Pu(VI)]: 0.1 to 0.8 M) and [H 2 O 2 ]/[Pu(VI)] ratio (from 1 to 8). Thus, the domain of Pu(IV) peroxide formation and the reactional paths were established. With the exception of 0.5 M nitric acid medium, the kinetic curves show two distinct regims: the first one corresponds to an induction period where the Pu(VI) concentration doesn't change, the second corresponds to a linear decrease of Pu(VI). An increase of the temperature greatly accelerates the Pu(VI) reduction rate while [H 2 O 2 ]/[Pu(VI)] has almost no influence. The Pu(VI) total reduction time decreases when initial concentration of plutonium increases. By increasing nitric acid concentration from 0.5 M to 6 M, the total Pu(VI) reduction time decreases. This time increases when [HNO 3 ] varies from 6 M to 8 M. (orig.)

Synthesis and application of magnetic hydrogel for Cr(VI) removal from contaminated water

KAUST Repository

Tang, Samuel C N; Wang, Peng; Yin, Ke; Lo., Irene Man Chi

2010-01-01

Many magnetic adsorbents reported in the literature, such as iron oxides, for Cr(VI) removal have been found effective only in low pH environments. Moreover, the application of polymeric hydrogels on heavy metal removal has been hindered by difficulties in separation by filtration. In this study, a magnetic cationic hydrogel was synthesized for Cr(VI) removal from contaminated water, making use of the advantages of magnetic adsorbents and polymeric hydrogels. The magnetic hydrogel was produced by imbedding 10-nm γ-Fe2O 3 nanoparticles into the polymeric matrix via radical polymerization. Characterization of the hydrogel was undertaken with Fourier transform infrared and vibrating sample magnetometer; swelling properties were tested and anionic adsorption capacity was evaluated. The magnetic hydrogel showed a superior Cr(VI) removal capacity compared to commercial products such as MIEX®. Cr(VI) removal was independent of solution pH. Results show that Cr(VI) removal kinetics was improved drastically by grinding the bulk hydrogel into powder form. At relevant concentrations, common water anions (e.g., Cl-, SO4 2-, PO4 3-) and natural organic matter did not exhibit significant inhibition of Cr(VI) adsorption onto the hydrogel. Results of vibrating sample magnetometer indicate that the magnetic hydrogel can be easily separated from treatment systems. Regeneration of the magnetic hydrogel can be easily achieved by washing the Cr(VI)-loaded hydrogel with 0.5 M NaCl solution, with a recovery rate of about 90% of Cr(VI). © Copyright 2010, Mary Ann Liebert, Inc. 2010.

Synthesis and application of magnetic hydrogel for Cr(VI) removal from contaminated water

KAUST Repository

Tang, Samuel C N

2010-11-01

Many magnetic adsorbents reported in the literature, such as iron oxides, for Cr(VI) removal have been found effective only in low pH environments. Moreover, the application of polymeric hydrogels on heavy metal removal has been hindered by difficulties in separation by filtration. In this study, a magnetic cationic hydrogel was synthesized for Cr(VI) removal from contaminated water, making use of the advantages of magnetic adsorbents and polymeric hydrogels. The magnetic hydrogel was produced by imbedding 10-nm γ-Fe2O 3 nanoparticles into the polymeric matrix via radical polymerization. Characterization of the hydrogel was undertaken with Fourier transform infrared and vibrating sample magnetometer; swelling properties were tested and anionic adsorption capacity was evaluated. The magnetic hydrogel showed a superior Cr(VI) removal capacity compared to commercial products such as MIEX®. Cr(VI) removal was independent of solution pH. Results show that Cr(VI) removal kinetics was improved drastically by grinding the bulk hydrogel into powder form. At relevant concentrations, common water anions (e.g., Cl-, SO4 2-, PO4 3-) and natural organic matter did not exhibit significant inhibition of Cr(VI) adsorption onto the hydrogel. Results of vibrating sample magnetometer indicate that the magnetic hydrogel can be easily separated from treatment systems. Regeneration of the magnetic hydrogel can be easily achieved by washing the Cr(VI)-loaded hydrogel with 0.5 M NaCl solution, with a recovery rate of about 90% of Cr(VI). © Copyright 2010, Mary Ann Liebert, Inc. 2010.

Modeling of Cr(VI) Bioreduction Under Fermentative and Denitrifying Conditions

Science.gov (United States)

Molins, S.; Steefel, C.; Yang, L.; Beller, H. R.

2011-12-01

The mechanisms of bioreductive immobilization of Cr(VI) were investigated by reactive transport modeling of a set of flow-through column experiments performed using natural Hanford 100H aquifer sediment. The columns were continuously eluted with 5 μM Cr(VI), 5 mM lactate as the electron donor, and selected electron acceptors (tested individually). Here we focus on the two separate experimental conditions that showed the most removal of Cr(VI) from solution: fermentation and denitrification. In each case, a network of enzymatic and abiotic reaction pathways was considered to interpret the rate of chromate reduction. The model included biomass growth and decay, and thermodynamic limitations on reaction rates, and was constrained by effluent concentrations measured by IC and ICP-MS and additional information from bacterial isolates from column effluent. Under denitrifying conditions, Cr(VI) reduction was modeled as co-metabolic with nitrate reduction based on experimental observations and previous studies on a denitrifying bacterium derived from the Hanford 100H aquifer. The reactive transport model results supported this interpretation of the reaction mechanism and were used to quantify the efficiency of the process. The models results also suggest that biomass growth likely relied on a nitrogen source other than ammonium (e.g. nitrate). Under fermentative conditions and based on cell suspension studies performed on a bacterial isolate from the columns, the model assumes that Cr(VI) reduction is carried out directly by fermentative bacteria that convert lactate into acetate and propionate. The evolution to complete lactate fermentation and Cr(VI) reduction took place over a week's time and simulations were used to determine an estimate for a lower limit of the rate of chromate reduction by calibration with the flow-through column experimental results. In spite of sulfate being added to these columns, sulfate reduction proceeded at a slow rate and was not well

Uranium(VI) retention by Ca-bentonite under (hyper)alkaline conditions

Energy Technology Data Exchange (ETDEWEB)

Philipp, Thimo; Schmeide, Katja [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes

2017-06-01

The sorption behavior of U(VI) on Ca-bentonite was studied in saline, (hyper)alkaline solution via batch experiments. At pH 8.5-9.5 sorption is low in the presence of CO{sub 2} due to the formation of weakly sorbing uranyl carbonate species, which have been observed to dominate speciation up to pH 10 by time-resolved laser-induced fluorescence spectroscopy (TRLFS). In the pH region 10-12, U(VI) retention is almost complete. The retention can either be attributed to strongly sorbing uranyl hydroxo complexes or to a partial precipitation of uranium due to an altered solubility of U(VI) induced by ions leached out of the bentonite.

Application of NKF-6 zeolite for the removal of U(VI) from aqueous solution

International Nuclear Information System (INIS)

Pengfei Zong; Hai Wang; Hui Pan; Yaolin Zhao; Chaohui He

2013-01-01

To better understand the application of NKF-6 zeolite as an adsorbent for the removal of U(VI) from radionuclides and heavy metal ions polluted water, herein, NKF-6 zeolite was employed to remove U(VI) at different experimental conditions. The influence of solid/liquid ratio, contact time, pH, ionic strength, humic substances and temperature on sorption of U(VI) to NKF-6 zeolite was investigated using batch technique under ambient conditions. The experimental results demonstrated that the sorption of U(VI) on NKF-6 zeolite was strongly dependent on pH. The sorption property of U(VI) was influenced by ionic strength at pH 7.0. The presence of fulvic acid or humic acid promoted the sorption of U(VI) on NKF-6 zeolite at low pH values while restrained the sorption at high pH values. The thermodynamic parameters (i.e., ΔS 0 , ΔH 0 , and ΔG 0 ) calculated from the temperature-dependent sorption isotherms demonstrated that the sorption process of U(VI) on NKF-6 zeolite was endothermic and spontaneous. At low pH values, the sorption of U(VI) was dominated by outer-sphere surface complexation and ion exchange with Na + /H + on NKF-6 zeolite surfaces, while inner-sphere surface complexation was the main sorption mechanism at high pH values. From the experimental results, one can conclude that NKF-6 zeolite can be used as a potential adsorbent for the preconcentration and solidification of U(VI) from large volumes of aqueous solutions. (author)

Remediation of uranium contaminated soils with bicarbonate extraction and microbial U(VI) reduction

Science.gov (United States)

Philips , Elizabeth J.P.; Landa, Edward R.; Lovely, Derek R.

1995-01-01

A process for concentrating uranium from contaminated soils in which the uranium is first extracted with bicarbonate and then the extracted uranium is precipitated with U(VI)-reducing microorganisms was evaluated for a variety of uranuum-contaminated soils. Bicarbonate (100 mM) extracted 20–94% of the uranium that was extracted with nitric acid. The U(VI)-reducing microorganism,Desulfovibrio desulfuricans reduced the U(VI) to U(IV) in the bicarbonate extracts. In some instances unidentified dissolved extracted components, presumably organics, gave the extract a yellow color and inhibited U(VI) reduction and/or the precipitation of U(IV). Removal of the dissolved yellow material with the addition of hydrogen peroxide alleviated this inhibition. These results demonstrate that bicarbonate extraction of uranium from soil followed by microbial U(VI) reduction might be an effective mechanism for concentrating uranium from some contaminated soils.

Remediation of uranium contaminated soils with bicarbonate extraction and microbial U(VI) reduction

International Nuclear Information System (INIS)

Phillips, E.J.P.; Landa, E.R.; Lovley, D.R.

1995-01-01

A process for concentrating uranium from contaminated soils in which the uranium is first extracted with bicarbonate and then the extracted uranium is precipitated with U(VI)-reducing microorganisms was evaluated for a variety of uranium-contaminated soils. Bicarbonate (100 mM) extracted 20-94% of the uranium that was extracted with nitric acid. The U(VI)-reducing microorganism, Desulfovibrio desulfuricans reduced the U(VI) to U(IV) in the bicarbonate extracts. In some instances unidentified dissolved extracted components, presumably organics, gave the extract a yellow color and inhibited U(VI) reduction and/or the precipitation of U(IV). Removal of the dissolved yellow material with the addition of hydrogen peroxide alleviated this inhibition. These results demonstrate that bicarbonate extraction of uranium from soil followed by microbial U(VI) reduction might be an effective mechanism for concentrating uranium from some contaminated soils. (author)

Osteogenesis Imperfecta Type VI in Individuals from Northern Canada.

Science.gov (United States)

Ward, Leanne; Bardai, Ghalib; Moffatt, Pierre; Al-Jallad, Hadil; Trejo, Pamela; Glorieux, Francis H; Rauch, Frank

2016-06-01

Osteogenesis imperfecta (OI) type VI is a recessively inherited form of OI that is caused by mutations in SERPINF1, the gene coding for pigment-epithelium derived factor (PEDF). Here, we report on two apparently unrelated children with OI type VI who had the same unusual homozygous variant in intron 6 of SERPINF1 (c.787-10C>G). This variant created a novel splice site that led to the in-frame addition of three amino acids to PEDF (p.Lys262_Ile263insLeuSerGln). Western blotting showed that skin fibroblasts with this mutation produced PEDF but failed to secrete it. Both children were treated with intravenous bisphosphonates, but the treatment of Individual 1 was switched to subcutaneous injections of denosumab (dose 1 mg per kg body weight, repeated every 3 months). An iliac bone sample obtained after 5 denosumab injections (and 3 months after the last injection) showed no change in the increased osteoid parameters that are typical of OI type VI, but the number of osteoclasts in trabecular bone was markedly increased. This suggests that the effect of denosumab on osteoclast suppression is of shorter duration in children with OI type VI than what has previously been reported on adults with osteoporosis.

Chemistry of the Colloidal Group II-VI Nanocrystal Synthesis

International Nuclear Information System (INIS)

Liu, Haitao

2007-01-01

In the last two decades, the field of nanoscience and nanotechnology has witnessed tremendous advancement in the synthesis and application of group II-VI colloidal nanocrystals. The synthesis based on high temperature decomposition of organometallic precursors has become one of the most successful methods of making group II-VI colloidal nanocrystals. This method is first demonstrated by Bawendi and coworkers in 1993 to prepare cadmium chalcogenide colloidal quantum dots and later extended by others to prepare other group II-VI quantum dots as well as anisotropic shaped colloidal nanocrystals, such as nanorod and tetrapod. This dissertation focuses on the chemistry of this type of nanocrystal synthesis. The synthesis of group II-VI nanocrystals was studied by characterizing the molecular structures of the precursors and products and following their time evolution in the synthesis. Based on these results, a mechanism was proposed to account for the 2 reaction between the precursors that presumably produces monomer for the growth of nanocrystals. Theoretical study based on density functional theory calculations revealed the detailed free energy landscape of the precursor decomposition and monomer formation pathway. Based on the proposed reaction mechanism, a new synthetic method was designed that uses water as a novel reagent to control the diameter and the aspect ratio of CdSe and CdS nanorods

Kinetics of Cr(III) and Cr(VI) removal from water by two floating macrophytes.

Science.gov (United States)

Maine, M A; Hadad, H R; Sánchez, G; Caffaratti, S; Pedro, M C

2016-01-01

The aim of this work was to compare Cr(III) and Cr(VI) removal kinetics from water by Pistia stratiotes and Salvinia herzogii. The accumulation in plant tissues and the effects of both Cr forms on plant growth were also evaluated. Plants were exposed to 2 and 6 mg L(-1) of Cr(III) or Cr(VI) during 30 days. At the end of the experiment, Cr(VI) removal percentages were significantly lower than those obtained for Cr(III) for both macrophytes. Cr(III) removal kinetics involved a fast and a slow component. The fast component was primarily responsible for Cr(III) removal while Cr(VI) removal kinetics involved only a slow process. Cr accumulated principally in the roots. In the Cr(VI) treatments a higher translocation from roots to aerial parts than in Cr(III) treatments was observed. Both macrophytes demonstrated a high ability to remove Cr(III) but not Cr(VI). Cr(III) inhibited the growth at the highest studied concentration of both macrophytes while Cr(VI) caused senescence. These results have important implications in the use of constructed wetlands for secondary industrial wastewater treatment. Common primary treatments of effluents containing Cr(VI) consists in its reduction to Cr(III). Cr(III) concentrations in these effluents are normally below the highest studied concentrations in this work.

Box-Behnken experimental design for chromium(VI) ions removal by bacterial cellulose-magnetite composites.

Science.gov (United States)

Stoica-Guzun, Anicuta; Stroescu, Marta; Jinga, Sorin Ion; Mihalache, Nicoleta; Botez, Adriana; Matei, Cristian; Berger, Daniela; Damian, Celina Maria; Ionita, Valentin

2016-10-01

In this study bacterial cellulose-magnetite composites were synthesised for the removal of chromium(VI) from aqueous solutions. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis and X-ray Photoelectron Spectroscopy (XPS) were used to characterize the bacterial cellulose-magnetite composites and to reveal the uniform dispersion of nanomagnetite in the BC matrix. Magnetic properties were also measured to confirm the magnetite immobilization on bacterial cellulose membrane. The effects of initial Cr(VI) concentration, solution pH and solid/liquid ratio upon chromium removal were examined using the statistical Box-Behnken Design. Because of the possibility of magnetite dissolution during chromium(VI) adsorption, the degree of iron leaching was also analysed in the same conditions as Cr(VI) adsorption. From the factors affecting chromium(VI) adsorption the most important was solution pH. The highest Cr(VI) removal efficiency was observed at pH 4, accompanied by the lowest iron leaching in the solution. The adsorption experiments also indicated that the adsorption process of chromium(VI) is well described by Freundlich adsorption model. Our results proved that the BC-magnetite composites could be used for an efficient removal of chromium(VI) from diluted solutions with a minimum magnetite dissolution during operation. Copyright © 2016 Elsevier B.V. All rights reserved.

Reaction kinetics and oxidation products formation in the degradation of ciprofloxacin and ibuprofen by ferrate(VI).

Science.gov (United States)

Zhou, Zhengwei; Jiang, Jia-Qian

2015-01-01

The treatment of ciprofloxacin (CIP) and ibuprofen (IBU) in test solutions by ferrate(VI) was investigated in this study. A series of jar test was performed in bench-scale at pH 6-9 and ferrate(VI) dose of 1-5 mg L(-1). Results demonstrated that ferrate(VI) removed CIP from test solutions efficiently, with above 70% of reduction under study conditions. In contrary, the removal rates of IBU were very low, less than 25% in all conditions. Raising ferrate(VI) dose improved the treatment performance, while the influence of solution pH was not significant at pH 6-9 compared with that of ferrate(VI) dose. In addition, kinetic studies of ferrate(VI) with both compounds were carried out at pH 8 and pH 9 (20 °C). Ferrate(VI) had a much higher reactivity with CIP than IBU at pH 8 and pH 9, with CIP's apparent second-order rate constants of 113.7±6.3 M(-1) s(-1) and 64.1±1.0 M(-1) s(-1), respectively. The rate constants of ferrate(VI) with IBU were less than 0.2 M(-1) s(-1) at pH 8 and pH 9. Furthermore, seven oxidation products (OPs) were formed during CIP degradation by ferrate(VI). The attack on the piperazinyl ring of the CIP by ferrate(VI) appeared to lead to the cleavage or hydroxylation of the rings, and the attack on the quinolone moiety by ferrate(VI) might lead to the cleavage of the double bond at the six-member heterocyclic ring. No OPs of IBU were detected during ferrate(VI) oxidation due to very small part of IBU was degraded by ferrate(VI). Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of flavin compounds on uranium(VI) reduction- kinetic study using electrochemical methods with UV-vis spectroscopy

International Nuclear Information System (INIS)

Yamasaki, Shinya; Tanaka, Kazuya; Kozai, Naofumi; Ohnuki, Toshihiko

2017-01-01

The reduction of uranium hexavalent (U(VI)) to tetravalent (U(IV)) is an important reaction because of the change in its mobility in the natural environment. Although the flavin mononucleotide (FMN) has acted as an electron shuttle for the U(VI) reduction in vivo system, which is called an electron mediator, only the rate constant for the electron transfer from FMN to U(VI) has been determined. This study examined the rate constant for the U(VI) reduction process by three flavin analogues (riboflavin, flavin mononucleotide, flavin adenine dinucleotide) to elucidate their substituent group effect on the U(VI) reduction rate by electrochemical methods. The formation of the U(IV) was monitored by UV-vis spectrometry at 660 nm during the constant potential electrolysis of the U(VI) solution in the presence of the mediator. The cyclic voltammograms indicated that the three flavin analogues behaved as electron mediator to reduce U(VI). The logarithmic rate constant for the U(VI) reduction was related to the standard redox potential of the mediators. This linear relationship indicated that the redox-active group of the mediator and the substituent group of the mediator dominate capability of the U(VI) reduction and its rate, respectively. The apparent reduction potential of U(VI) increased about 0.2 V in the presence of the mediators, which strongly suggests that the biological electron mediator makes the U(VI) reduction possible even under more oxidative conditions. - Highlights: • The rate constant for the U(VI) reduction by flavin analogues was determined. • The flavins showed a mediator effect on the U(VI) reduction. • The logarithmic rate constants for the U(VI) reduction was proportional to redox potential of the mediator. • The presence of the mediator increased about 0.2 V apparent redox potential of U(VI) to U(IV).

Ryger troværdigheden ned, når vi taler læreruddannelsen op?

DEFF Research Database (Denmark)

Holm, Claus

2009-01-01

Nu er vi ved at få talt læreruddannelsen op af sin lavstatus. Resultatet er, at flere søger uddannelsen. Så må vi håbe, at talen er troværdig, for ellers vil frafaldet stige.......Nu er vi ved at få talt læreruddannelsen op af sin lavstatus. Resultatet er, at flere søger uddannelsen. Så må vi håbe, at talen er troværdig, for ellers vil frafaldet stige....

ColVI myopathies: where do we stand, where do we go?

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Allamand Valérie

2011-09-01

Full Text Available Abstract Collagen VI myopathies, caused by mutations in the genes encoding collagen type VI (ColVI, represent a clinical continuum with Ullrich congenital muscular dystrophy (UCMD and Bethlem myopathy (BM at each end of the spectrum, and less well-defined intermediate phenotypes in between. ColVI myopathies also share common features with other disorders associated with prominent muscle contractures, making differential diagnosis difficult. This group of disorders, under-recognized for a long time, has aroused much interest over the past decade, with important advances made in understanding its molecular pathogenesis. Indeed, numerous mutations have now been reported in the COL6A1, COL6A2 and COL6A3 genes, a large proportion of which are de novo and exert dominant-negative effects. Genotype-phenotype correlations have also started to emerge, which reflect the various pathogenic mechanisms at play in these disorders: dominant de novo exon splicing that enables the synthesis and secretion of mutant tetramers and homozygous nonsense mutations that lead to premature termination of translation and complete loss of function are associated with early-onset, severe phenotypes. In this review, we present the current state of diagnosis and research in the field of ColVI myopathies. The past decade has provided significant advances, with the identification of altered cellular functions in animal models of ColVI myopathies and in patient samples. In particular, mitochondrial dysfunction and a defect in the autophagic clearance system of skeletal muscle have recently been reported, thereby opening potential therapeutic avenues.

Thermodynamics of U(VI) and Eu(III) complexation by unsaturated carboxylates

Energy Technology Data Exchange (ETDEWEB)

Rawat, Neetika; Bhattacharyya, A. [Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Tomar, B.S., E-mail: bstomar@barc.gov.in [Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Ghanty, T.K. [Theoretical Chemistry Section, Bhabha Atomic Research Centre, Mumbai 400085 (India); Manchanda, V.K. [Radiochemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

2011-05-10

Highlights: {yields} {Delta}H and log K determined for U(VI) and Eu(III) complexes with maleate and fumarate. {yields} log K and coordination environment of Eu(III) complexes has been studied by TRFS. {yields} Higher log K of U(VI) complexes than Eu(III) complexes is due to higher entropy. {yields} Plot of log K vs log K{sub P} suggest charge polarization in fumarate complexes. {yields} Ab initio calculations support charge polarization in fumarate complexes. - Abstract: The thermodynamic parameters ({Delta}G, {Delta}H and {Delta}S) of complexation of U(VI) and Eu(III) by unsaturated dicarboxylic acids, namely, maleic and fumaric acid, has been determined by potentiometric and microcalorimetric titrations at fixed ionic strength (I = 1.0 M) and temperature (298 K). The results show formation of 1:1 complexes by both the ligands with Eu(III). In the case of U(VI), maleate forms both 1:1 and 1:2 complexes, while only 1:1 complex was formed with fumarate. The fluorescence emission spectra of Eu(III)-dicarboxylate solutions at varying ligand to metal ratio were also used to obtain their stability constants. In addition, the fluorescence lifetimes reveal higher dehydration of Eu(III)-maleate compared to Eu(III)-fumarate which corroborates the {Delta}S values. The thermodynamic quantities suggest charge polarization effects in the case of U(VI) and Eu(III) complexes of fumarate, which is further corroborated by theoretical calculations. For the same ligand, U(VI) complexes were found to be more stable which was mainly due to higher entropy term.

Transient groundwater chemistry near a river: Effects on U(VI) transport in laboratory column experiments

Science.gov (United States)

Yin, Jun; Haggerty, Roy; Stoliker, Deborah L.; Kent, Douglas B.; Istok, Jonathan D.; Greskowiak, Janek; Zachara, John M.

2011-01-01

In the 300 Area of a U(VI)-contaminated aquifer at Hanford, Washington, USA, inorganic carbon and major cations, which have large impacts on U(VI) transport, change on an hourly and seasonal basis near the Columbia River. Batch and column experiments were conducted to investigate the factors controlling U(VI) adsorption/desorption by changing chemical conditions over time. Low alkalinity and low Ca concentrations (Columbia River water) enhanced adsorption and reduced aqueous concentrations. Conversely, high alkalinity and high Ca concentrations (Hanford groundwater) reduced adsorption and increased aqueous concentrations of U(VI). An equilibrium surface complexation model calibrated using laboratory batch experiments accounted for the decrease in U(VI) adsorption observed with increasing (bi)carbonate concentrations and other aqueous chemical conditions. In the column experiment, alternating pulses of river and groundwater caused swings in aqueous U(VI) concentration. A multispecies multirate surface complexation reactive transport model simulated most of the major U(VI) changes in two column experiments. The modeling results also indicated that U(VI) transport in the studied sediment could be simulated by using a single kinetic rate without loss of accuracy in the simulations. Moreover, the capability of the model to predict U(VI) transport in Hanford groundwater under transient chemical conditions depends significantly on the knowledge of real-time change of local groundwater chemistry.

Nicomachean Ethics VI.9: good deliberation and phronesis [Ética a Nicômaco VI.9: boa deliberação e phronesis

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Angelo Antonio Pires de Oliveira

2017-08-01

Full Text Available In this paper, I put under scrutiny the arguments put forward by Aristotle in Nicomachean Ethics (NE VI.9. The paper has two main parts. In the first, I examine the NE VI.9’s first part where Aristotle develops the concept of good deliberation, offering its definition in 1142b27-28. In the second, I examine the connection between good deliberation and phronesis, and, then, discuss the vexata quæstio about if the lines 1142b31-33 might be read as introducing the claim that phronesis provides moral ends. [Neste artigo, analiso pormenorizadamente os argumentos apresentados por Aristóteles em Ética a Nicômaco (EN VI.9. O artigo é dividido em duas partes principais. Na primeira, abordo a primeira parte de EN VI.9 onde Aristóteles desenvolve a noção de boa deliberação, culminando com a apresentação da sua definição em 1142b27-28. Na segunda, abordo a conexão entre boa deliberação e phronesis e discuto a vexata quaestio de se as linhas 1142b31-33 podem ser lidas como introduzindo a tese de que a phronesis fornece os fins morais

Urinary carbonic anhydrase VI as a biomarker for kidney disease in pigs.

Science.gov (United States)

Nishita, Toshiho; Yatsu, Juro; Watanabe, Kazuo; Ochiai, Hideharu; Ichihara, Nobutsune; Orito, Kensuke; Arishima, Kazuyoshi

2014-11-01

This study investigated whether carbonic anhydrase (CA)-VI has utility as a biomarker in swine kidney disease. Serum chemistry, histopathology, immunohistochemical staining and enzyme-linked immunosorbent assay (ELISA) analyses were performed. In the kidney of normal healthy pigs, CA-VI was localized in the epithelial cells of the renal distal straight tubules. CA-VI levels were 16 ± 35 ng/g wet tissue and 50 ± 66 ng/mL in normal pig kidney and urine, respectively, and 136 ± 173 ng/mL in the urine of pigs with kidney disease. CA-VI urinary concentration was not correlated with urinary urea nitrogen (UUN), urinary creatinine (Cre), or urinary albumin levels in pigs with kidney disease. However, UUN and Cre levels were positively correlated in the urine of pigs with kidney disease. These data suggest that urinary CA-VI may represent a biomarker for kidney disease in pigs, particularly for disorders affecting distal straight tubules. Copyright © 2014 Elsevier Ltd. All rights reserved.

Influence of Calcite and Dissolved Calcium on Uranium(VI) Sorption to a Hanford Subsurface Sediment

International Nuclear Information System (INIS)

Dong, Wenming; Ball, William P.; Liu, Chongxuan; Wang, Zheming; Stone, Alan T.; Bai, Jing; Zachara, John M.

2005-01-01

The influence of calcite and dissolved calcium on U(VI) adsorption was investigated using a calcite-containing sandy silt/clay sediment from the U. S. Department of Energy Hanford site. U(VI) adsorption to sediment, treated sediment, and sediment size fractions was studied in solutions that both had and had not been preequilibrated with calcite, at initial [U(VI)] ) 10-7-10-5 mol/L and final pH ) 6.0- 10.0. Kinetic and reversibility studies (pH 8.4) showed rapid sorption (30 min), with reasonable reversibility in the 3-day reaction time. Sorption from solutions equilibrated with calcite showed maximum U(VI) adsorption at pH 8.4 (0.1. In contrast, calcium-free systems showed the greatest adsorption at pH 6.0-7.2. At pH > 8.4, U(VI) adsorption was identical from calcium-free and calcium-containing solutions. For calcite-presaturated systems, both speciation calculations and laser-induced fluorescence spectroscopic analyses indicated that aqueous U(VI) was increasingly dominated by Ca2UO2(CO3)3 0(aq) at pH<8.4 and that formation of Ca2UO2(CO3)3 0(aq) is what suppresses U(VI) adsorption. Above pH 8.4, aqueous U(VI) speciation was dominated by UO2(CO3)3 4- in all solutions. Finally, results also showed that U(VI) adsorption was additive in regard to size fraction but not in regard to mineral mass: Carbonate minerals may have blocked U(VI) access to surfaces of higher sorption affinity

combined effect of polyaniline emeraldine salt for removal of Cr(VI)

Indian Academy of Sciences (India)

Cr(VI) ion is one of the major industrial wastes as dichromate and chromate ions are ... more [9–12]. For the toxic nature of Cr(VI) in aqueous medium, it becomes a ... techniques such as adsorption [13–15], chemical reduction. [16], reverse ...

Probing uranyl(VI) speciation in the presence of amidoxime ligands using electrospray ionization mass spectrometry.

Science.gov (United States)

Mustapha, Adetayo M; Pasilis, Sofie P

2013-10-15

Extraction processes using poly(acrylamidoxime) resins are being developed to extract uranium from seawater. The main complexing agents in these resins are thought to be 2,6-dihydroxyiminopiperidine (DHIP) and N(1),N(5)-dihydroxypentanediimidamide (DHPD), which form strong complexes with uranyl(VI) at the pH of seawater. It is important to understand uranyl(VI) speciation in the presence of these and similar amidoxime ligands to understand factors affecting uranyl(VI) adsorption to the poly(acrylamidoxime) resins. Experiments were carried out in positive ion mode on a quadrupole ion trap mass spectrometer equipped with an electrospray ionization source. The ligands investigated were DHIP, DHPD, and N(1),N(2)-dihydroxyethanediimidamide (DHED). DHED and DHPD differ only in the number of carbons separating the oxime groups. The effects on the mass spectra of changes in uranyl(VI):ligand ratio, pH, and ligand type were examined. DHIP binds uranyl(VI) more effectively than DHPD or DHED in the pH range investigated, forming ions derived from solution-phase species with uranyl(VI):DHIP stoichiometries of 1:1, 1:2, and 2:3. The 2:3 uranyl(VI):DHIP complex appears to be a previously undescribed solution species. Ions related to uranyl(VI):DHPD complexes were detected in very low abundance. DHED is a more effective complexing agent for uranyl(VI) than DHPD, forming ions having uranyl(VI):DHED stoichiometries of 1:1, 1:2, 1:3, and 2:3. This study presents a first look at the solution chemistry of uranyl(VI)-amidoxime complexes using electrospray ionization mass spectrometry. The appearance of previously undescribed solution species suggests that the uranyl-amidoxime system is a rich and relatively complex one, requiring a more in-depth investigation. Copyright © 2013 John Wiley & Sons, Ltd.

Surface complexation modeling of the effects of phosphate on uranium(VI) adsorption

Energy Technology Data Exchange (ETDEWEB)

Romero-Gonzalez, M.R.; Cheng, T.; Barnett, M.O. [Auburn Univ., AL (United States). Dept. of Civil Engeneering; Roden, E.E. [Wisconsin Univ., Madison, WI (United States). Dept. of Geology and Geophysics

2007-07-01

Previous published data for the adsorption of U(VI) and/or phosphate onto amorphous Fe(III) oxides (hydrous ferric oxide, HFO) and crystalline Fe(III) oxides (goethite) was examined. These data were then used to test the ability of a commonly-used surface complexation model (SCM) to describe the adsorption of U(VI) and phosphate onto pure amorphous and crystalline Fe(III) oxides and synthetic goethite-coated sand, a surrogate for a natural Fe(III)-coated material, using the component additivity (CA) approach. Our modeling results show that this model was able to describe U(VI) adsorption onto both amorphous and crystalline Fe(III) oxides and also goethite-coated sand quite well in the absence of phosphate. However, because phosphate adsorption exhibits a stronger dependence on Fe(III) oxide type than U(VI) adsorption, we could not use this model to consistently describe phosphate adsorption onto both amorphous and crystalline Fe(III) oxides and goethite-coated sand. However, the effects of phosphate on U(VI) adsorption could be incorporated into the model to describe U(VI) adsorption to both amorphous and crystalline Fe(III) oxides and goethite-coated sand, at least for an initial approximation. These results illustrate both the potential and limitations of using surface complexation models developed from pure systems to describe metal/radionuclide adsorption under more complex conditions. (orig.)

Surface complexation modeling of the effects of phosphate on uranium(VI) adsorption

International Nuclear Information System (INIS)

Romero-Gonzalez, M.R.; Cheng, T.; Barnett, M.O.; Roden, E.E.

2007-01-01

Previous published data for the adsorption of U(VI) and/or phosphate onto amorphous Fe(III) oxides (hydrous ferric oxide, HFO) and crystalline Fe(III) oxides (goethite) was examined. These data were then used to test the ability of a commonly-used surface complexation model (SCM) to describe the adsorption of U(VI) and phosphate onto pure amorphous and crystalline Fe(III) oxides and synthetic goethite-coated sand, a surrogate for a natural Fe(III)-coated material, using the component additivity (CA) approach. Our modeling results show that this model was able to describe U(VI) adsorption onto both amorphous and crystalline Fe(III) oxides and also goethite-coated sand quite well in the absence of phosphate. However, because phosphate adsorption exhibits a stronger dependence on Fe(III) oxide type than U(VI) adsorption, we could not use this model to consistently describe phosphate adsorption onto both amorphous and crystalline Fe(III) oxides and goethite-coated sand. However, the effects of phosphate on U(VI) adsorption could be incorporated into the model to describe U(VI) adsorption to both amorphous and crystalline Fe(III) oxides and goethite-coated sand, at least for an initial approximation. These results illustrate both the potential and limitations of using surface complexation models developed from pure systems to describe metal/radionuclide adsorption under more complex conditions. (orig.)

Det digitale interaktive fjernsyn i hverdagslivet

Directory of Open Access Journals (Sweden)

Thomas Bjørner

2007-04-01

Full Text Available Digitaliseringen af tv-mediet er allerede i fuld gang, og der er i Danmark fastlagt en analog slukdato for public servicekanalerne i 2009. I forlængelse heraf leverer denne artikel en række indsigter i, hvordan den nye teknologi potentielt forandrer hverdagen, men samtidig er det også en pointe, at den digitale teknologi indpasses i eksisterende mønstre for tv-sening. Med baggrund i forsøgskanalen TV2/Nord-Digital, som var den første kanal der udsendte digitalt interaktivt tv i Danmark, vil denne artikel give nogle svar på, hvad der sker når digitalt tv (med de øgede interaktive muligheder vinder indpas i husstanden. Hvem skal bestemme i forhold til hvad der skal ses af interaktivt indhold? Vil digitaliseringen dermed fremme den stigende tendens til at vi ser mere tv hver for sig? Og ønsker seerne overhovedet at være interaktive med deres fjernsyn – og i givet fald om hvad og hvorfor?

BUDIDAYA UDANG VANAME (Litopenaeus vannamei TEKNOLOGI INTENSIF MENGGUNAKAN BENIH TOKOLAN

Directory of Open Access Journals (Sweden)

Markus Mangampa

2016-11-01

Full Text Available Salah satu jenis udang yang cukup potensial untuk dikembangkan adalah udang vaname (Litopenaeus vannamei. Budidaya ini berkembang dengan teknologi intensif, namun terbatas pada golongan masyarakat menengah ke atas (padat modal. Riset ini bertujuan untuk mendapatkan data dan informasi pengaruh penggunaan tokolan terhadap produksi, Rasio Konversi Pakan (RKP pada pembesaran udang vaname teknologi intensif. Riset ini dilaksanakan di tambak Punaga, Takalar, Instalasi Balai Riset Perikanan Budidaya Air Payau (BRPBAP, menggunakan empat petak masing masing berukuran 4.000 m2/petak. Hewan uji adalah udang vaname dengan perlakuan: (A pembesaran dengan tebar benur (PL-12, dan (B pembesaran dengan tebar tokolan (PL-27. Setiap perlakuan dengan 2 ulangan, kepadatan benur dan tokolan adalah 50 ekor/m2, dan pemeliharaan berlangsung 80 hari di tambak. Hasil yang diperoleh pada perlakuan B memperlihatkan pertumbuhan mutlak (11,114±0,258 g/ekor, sintasan (92,55±0,23%, produksi (2.087,5±88,2 kg/petak lebih tinggi daripada perlakuan A yaitu: pertumbuhan mutlak (10,085±0,120 g/ekor, sintasan (90,83±8,51%, produksi (1.831,0±149,9 kg/petak, namun ketiga peubah ini berbeda tidak nyata antara kedua perlakuan. RKP lebih rendah pada perlakuan B (1,096±0,034 berbeda nyata dengan perlakuan A (1,257±0,048. Peubah kualitas air memperlihatkan sebaran kisaran yang merata untuk kedua perlakuan, kecuali nitrit (NO2 memperlihatkan kisaran yang tinggi pada perlakuan B (0,18235 mg/L dibandingkan dengan perlakuan A (0,0328 mg/L pada akhir penelitian. Hal ini disebabkan waktu panen yang berbeda sesuai dengan kondisi musim yaitu kualitas air sumber semakin menurun. Kualitas air sumber yang menurun ini diikuti oleh meningkatnya total vibrio di air laut mencapai; 4,33104 cfu/mL dibandingkan dalam air tambak 829.102 cfu/mL. Kesimpulan memperlihatkan bahwa penggunaan tokolan (PL-27 menghasilkan produksi yang tinggi dan rasio konversi pakan yang rendah. One species of shrimps that

Modeling of kinetics of Cr(VI) sorption onto grape stalk waste in a stirred batch reactor

International Nuclear Information System (INIS)

Escudero, Carlos; Fiol, Nuria; Poch, Jordi; Villaescusa, Isabel

2009-01-01

Recently, Cr(VI) removal by grape stalks has been postulated to follow two mechanisms, adsorption and reduction to trivalent chromium. Nevertheless, the rate at which both processes take place and the possible simultaneity of both processes has not been investigated. In this work, kinetics of Cr(VI) sorption onto grape stalk waste has been studied. Experiments were carried out at different temperatures but at a constant pH (3 ± 0.1) in a stirred batch reactor. Results showed that three steps take place in the process of Cr(VI) sorption onto grape stalk waste: Cr(VI) sorption, Cr(VI) reduction to Cr(III) and the adsorption of the formed Cr(III). Taking into account the evidences above mentioned, a model has been developed to predict Cr(VI) sorption on grape stalks on the basis of (i) irreversible reduction of Cr(VI) to Cr(III) reaction, whose reaction rate is assumed to be proportional to the Cr(VI) concentration in solution and (ii) adsorption and desorption of Cr(VI) and formed Cr(III) assuming that all the processes follow Langmuir type kinetics. The proposed model fits successfully the kinetic data obtained at different temperatures and describes the kinetics profile of total, hexavalent and trivalent chromium. The proposed model would be helpful for researchers in the field of Cr(VI) biosorption to design and predict the performance of sorption processes.

Biological detoxification of Cr(VI) using wood-husk immobilized Acinetobacter haemolyticus

International Nuclear Information System (INIS)

Zakaria, Zainul Akmar; Zakaria, Zainoha; Surif, Salmijah; Ahmad, Wan Azlina

2007-01-01

Acinetobacter haemolyticus, a Gram-negative aerobic locally isolated bacterium, immobilized on wood-husk showed the ability to detoxify Cr(VI) to Cr(III). Wood-husk, a natural cellulose-based support material, packed in an upward-flow column was used as support material for bacterial attachment. Around 97% of the Cr(VI) in wastewater containing 15 mg L -1 of Cr(VI) was reduced at a flow rate of 8.0 mL min -1 . The wastewater containing Cr(VI) was added with liquid pineapple wastewater as nutrient source for the bacteria. Electron microscopic examinations of the wood-husk after 42 days of column operation showed gradual colonization of the wood-husk by bacterial biofilm. The use of 0.1% (v/v) formaldehyde as a disinfecting agent inhibited growth of bacteria present in the final wastewater discharge. This finding is important in view of the ethical code regarding possible introduction of exogenous bacterial species into the environment

Biological detoxification of Cr(VI) using wood-husk immobilized Acinetobacter haemolyticus

Energy Technology Data Exchange (ETDEWEB)

Zakaria, Zainul Akmar; Zakaria, Zainoha [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia); Surif, Salmijah [Department of Environmental Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Ahmad, Wan Azlina [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 Skudai, Johor (Malaysia)], E-mail: azlina@kimia.fs.utm.my

2007-09-05

Acinetobacter haemolyticus, a Gram-negative aerobic locally isolated bacterium, immobilized on wood-husk showed the ability to detoxify Cr(VI) to Cr(III). Wood-husk, a natural cellulose-based support material, packed in an upward-flow column was used as support material for bacterial attachment. Around 97% of the Cr(VI) in wastewater containing 15 mg L{sup -1} of Cr(VI) was reduced at a flow rate of 8.0 mL min{sup -1}. The wastewater containing Cr(VI) was added with liquid pineapple wastewater as nutrient source for the bacteria. Electron microscopic examinations of the wood-husk after 42 days of column operation showed gradual colonization of the wood-husk by bacterial biofilm. The use of 0.1% (v/v) formaldehyde as a disinfecting agent inhibited growth of bacteria present in the final wastewater discharge. This finding is important in view of the ethical code regarding possible introduction of exogenous bacterial species into the environment.

Cr(VI) adsorption from electroplating plating wastewater by chemically modified coir pith.

Science.gov (United States)

Suksabye, Parinda; Thiravetyan, Paitip

2012-07-15

Coir pith samples were chemically modified by grafting with acrylic acid for the removal of Cr(VI) from electroplating wastewater. The presence of acrylic acid on the coir pith surface was verified by a scanning electron microscope with an electron dispersive x-ray spectrometer (SEM/EDX), Fourier transform infrared spectroscopy (FTIR) and thermogravimetry (TG). The carbonyl groups (C==O) from the carboxylic acids (COOH) increased on the coir pith surface after grafting with acrylic acid. In addition, the thermal stability of the acrylic acid-grafted coir pith also improved. The optimum conditions for grafting the acrylic acid on the coir pith consisted of 2 M acrylic acid and 0.00125 M ceric ammonium nitrate (CAN, as an initiator). The maximum Cr(VI) removal (99.99 ± 0.07%) was obtained with the following conditions: a 1.3% (w/v) dosage of acrylic acid-grafted coir pith, a system pH of 2, a contact time of 22 h, a temperature of 30 °C, a particle size of <150 μm and an initial Cr(VI) of 1,171 mg l(-1). At system pH of 2, Cr(VI) in the HCrO(4)(-) form can be adsorbed with acrylic acid-grafted coir pith via an electrostatic attraction. The adsorption isotherm of 2 M acrylic acid-grafted coir pith exhibited a good fit with the Langmuir isotherm. The maximum Cr(VI) adsorption capacity of the 2 M acrylic acid-grafted coir pith was 196.00 mg Cr(VI) g(-1) adsorbent, whereas for coir pith without grafting, the maximum Cr(VI) removal was 165.00 mg Cr(VI) g(-1) adsorbent. The adsorption capacity of the acrylic acid-grafted coir pith for Cr(VI) was higher compared to the original coir pith. This result was due to the enhancement of the carbonyl groups on the coir pith surface that may have involved the mechanism of chromium adsorption. The X-ray absorption near edged structure (XANES) and desorption studies suggested that most of the Cr(III) that presented on the acrylic acid-grafted coir pith was due to the Cr(VI) being reduced to Cr(III) on the adsorbent surface. FTIR

Formation of nitridotechnetium(VI) μ-oxo dimer complexes with EDTA and EDDA

International Nuclear Information System (INIS)

Takayama, T.; Kani, Y.; Sekine, T.; Kudo, H.; Yoshihara, K.

1995-01-01

Reactions of [ 99 TcNCl 4 ] - with ethylenediaminetetraacetic acid 4 (ETDA) and ethylenediamine-N,N'-diacetic acid (EDDA) in a mixture of water and acetone gave Tc VI N-EDTA and Tc VI N-EDTA complexes. The infrared spectra of both reaction products showed the existence of the Tc≡N and C=O groups. The elemental analysis indicated the 1:1 TcN-ligand ratio in the EDTA and EDDA complexes. Electrophoresis showed that the Tc VI -EDTA complex was an anionic species in a perchlorate solution. For the Tc VI N-EDDA complex, neutral and anionic species were formed, depending on the pH of the solution. Formation of the μ-oxo dimer complexes was suggested from the UV-Vis absorption spectra. (author) 11 refs.; 4 figs.; 1 tab

Study on Adsorption of Chromium (VI) by Activated Carbon from Cassava Sludge

Science.gov (United States)

Yang, Jinhui; Li, Chuanshu; Yang, Bin; Kang, Sijun; Zhang, Zhen

2018-03-01

In this paper, a new type of adsorbent prepared by waste sludge from alcohol production industry was used to adsorb Cr (VI) in activated carbon from cassava sludge. A series of static adsorption experiments were carried out on the initial concentration of solution Cr (VI), pH value of solution, adsorption time and dosage of adsorbent. The results of single factor experiments show that the removal rate of Cr (VI) increases with the initial concentration of Cr(VI), while the adsorption amount is opposite. When the pH value of the solution is low, the adsorption effect of activated carbon is better.The adsorption time should be controlled within 40-60min. When the activated carbon dosage is increased, the removal rate increases but the adsorption capacity decreases.

Spectroscopic Studies on Complex Formation of U(VI)-thiosalicylate

Energy Technology Data Exchange (ETDEWEB)

Cha, Wan Sik; Cho, Hye Ryun; Park, Kyoung Kyun; Jung, Euo Chang [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2011-05-15

The dynamic interaction between radionuclides and organic ligands is largely dependent on the composition of functional groups in a ligand chemical structure. Therefore, the structural mimics of natural ligands possessing specific functional groups, such as hydroxy, phenol, carboxyl, thiol and amine groups, have been studied to understand their influence on the migration of radionuclides including actinide species under geological groundwater conditions. In previous studies, we demonstrated that the fraction of hydrolyzed U(VI) species occurring in weak acidic solutions (pH {approx}4.5) is significantly influenced by the presence of salicylate (Sal) ligand due to the simultaneous participation of both phenol and carboxyl groups in the formation of U(VI)-complexes. Thiosalicylic acid (TSalH{sub 2}) is a good model compound for studying the effects of both carboxyl and thiol (-SH) groups. The fraction of di-anionic ligand form (TSal{sup 2-}) is higher at near neutral pH due to the lower pKa ({approx} 8) of the thiol group than the case of salicylic acid (pKa, {approx}13 for salicylic -OH), despite the structural similarity. In addition, the redox capability of the thiol group is expected to influence the reducible radiouclides and the chemical structures of natural ligands by creating cross-linkage (-S-S-) upon oxidation. The goal of the present study is to investigate aqueous U(VI)-TSal complexation equilibrium via laser-based spectroscopic techniques including time resolved laser-induced fluorescence spectroscopy (TRLFS). In this preliminary work, we report the results of spectroscopic studies using conventional UVVis absorbance and fluorescence (FL) measurement methods. The photo-stability of U(VI)-TSal complex or ligand itself upon exposure to a series of laser pulses is estimated by monitoring the change in their absorption bands. Additionally, TSal FL-quenching effect by U(VI) ions is discussed in comparison with that of Sal FL-quenching

Determination of chromium (VI) in primary and secondary fertilizer and their respective precursors.

Science.gov (United States)

Krüger, Oliver; Fiedler, Francesca; Adam, Christian; Vogel, Christian; Senz, Rainer

2017-09-01

Hexavalent chromium species (Cr(VI)) are often carcinogenic, of high acute toxicity, highly mobile, and thus pose a severe risk to health and environment. Fertilizers usually contain significant amounts of chromium. Therefore, a reliable analysis of chromium and the fraction of Cr(VI) are crucial for safe use of fertilizers. This problem is expected to increase in the future, since more and more recycled fertilizers emerge due to increasing fertilizer demand and respective supply risks. However, existing analytical methods have been developed for conventional fertilizers and have to be tested whether they are suitable for the new materials. Thus, we performed a wet-chemical extraction for Cr(VI) on several matrices as well as respective quality control experiments including spiking with Cr(III) and Cr(VI) compounds. We found the Cr(VI) amounts to be below 2 mg/kg except for a thermally post-treated sewage sludge ash (SSA) that showed 12.3 mg/kg. The presence of organic matter e.g. in sludge or precipitated struvite caused a reduction of spiked Cr(VI) and thus no satisfying recovery for quality control. Cr(VI) reduction was also observed for SSA, presumably due to the presence of Fe(II) compounds. Even though the tested procedure can be hampered in some recycled fertilizer matrices, it might be adapted to be applicable also for these complex samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

Can iron oxides remove Cr(VI) from drinking water at sub-ppb levels?

Science.gov (United States)

Kaprara, Efthymia; Simeonidis, Konstantinos; Samaras, Petros; Zouboulis, Anastasios; Mitrakas, Manassis

2013-04-01

Hexavalent chromium [Cr(VI)] has long been recognized as a potential carcinogen via inhalation, in contrast to trivalent chromium [Cr(III)] which is 100 times less toxic and also a necessary nutrient, essential to human glucidic metabolism. Nowadays there is an increasing concern that Cr(VI) is also carcinogenic by the oral route of exposure, while an increased number of publications indicate that Cr(VI) is a common natural pollutant. Hexavalent chromium formation is attributed to natural oxidation of Cr(III) in ultramafic derived soils and ophiolithic rocks. To verify this theory, drinking water samples were collected from targeted areas of Greece e.g. areas in which the geological background is predominated by ultramafic minerals and the water supply depends mainly on groundwater resources. Valuable guide for the samples collection was the geological map of Greece and emphasis was given to regions where the natural occurrence of Cr(VI) is thought to be more possible. A wide range of Cr concentrations (2-100 μg/L) were detected in the areas studied, with most of them ranging below the current limit of 50 μg/L, and the Cr(VI) concentration being more than 90% of the total. Since the Cr(VI) affects significant part of population worldwide, a debate was established concerning the enforcement of stringent regulation, which also demands the drinking water treatment processes re-evaluation in view of Cr(VI) removal at sub-ppb level. In this regard, adsorption has evolved as the front line of defense for chromium removal. The motivation of this work was to investigate the efficiency of iron oxides for the adsorption of Cr(VI) from drinking water and its removal at sub-ppb levels. The adsorbents examined included iron oxy-hydroxides and magnetite prepared using common low cost iron salts. Their effectiveness as Cr(VI) adsorbents was evaluated through the decrease of a Cr(VI) concentration of 100μg/L prepared in NSF water at pH 7. Preliminary batch experiments did not

Influence of chemical compositions and molecular weights of humic acids on Cr(VI) photo-reduction

International Nuclear Information System (INIS)

Chen, S.Y.; Huang, S.W.; Chiang, P.N.; Liu, J.C.; Kuan, W.H.; Huang, J.H.; Hung, J.T.; Tzou, Y.M.; Chen, C.C.; Wang, M.K.

2011-01-01

Highlights: ► Low molecular weights (M w ) of HA bear more polar and aromatic C in its structure. ► The polar sites of HA dominate the photo-reduction of Cr(VI). ► Low M w of HA exhibits greater photochemical efficiency for Cr(VI) reduction. ► Cr(VI) adsorption on HA is indiscernible, particularly on the small M w of HA. ► Upon Cr(VI) reduction by HA, most of Cr(III) are released into the solution. - Abstract: Humic acids (HA) strongly affect the fate of trace metals in soils and aquatic environments. One of the remarkable properties of HA is its ability to reduce Cr(VI), an extremely toxic anion. However, it is unclear which HA components are involved in Cr(VI) reduction and possess the photo-induced properties. In this study, an ultrafiltration technique was used to fractionate HAs into four fractions of different nominal molecular weights (M w ): >100, 50–100, 10–50 and w HA was enriched with polar and aromatic domains. These polar, including polar C in aliphatic region, and aromatic groups were the major sites for Cr(VI) reduction because they disappeared rapidly upon interaction with Cr(VI). As a result, low M w of HA exhibited greater efficiency of Cr(VI) reduction. Light induced the rapid transfer of electrons between chromate-phenol/carboxyl ester, or the formation of peroxide radicals or H 2 O 2 through the ready decay of peroxy radicals associated with polar substituents, explained the rapid scavenging of Cr(VI) on polar and aromatic groups of HAs under illumination.

Kinetics of Uranium(VI) Desorption from Contaminated Sediments: Effect of Geochemical Conditions and Model Evaluation

International Nuclear Information System (INIS)

Liu, Chongxuan; Shi, Zhenqing; Zachara, John M.

2009-01-01

Stirred-flow cell experiments were performed to investigate the kinetics of uranyl (U(VI)) desorption from a contaminated sediment collected from the Hanford 300 Area at the US Department of Energy (DOE) Hanford Site, Washington. Three influent solutions of variable pH, Ca and carbonate concentrations that affected U(VI) aqueous and surface speciation were used under dynamic flow conditions to evaluate the effect of geochemical conditions on the rate of U(VI) desorption. The measured rate of U(VI) desorption varied with solution chemical composition that evolved as a result of thermodynamic and kinetic interactions between the influent solutions and sediment. The solution chemical composition that led to a lower equilibrium U(VI) sorption to the solid phase yielded a faster desorption rate. The experimental results were used to evaluate a multi-rate, surface complexation model (SCM) that has been proposed to describe U(VI) desorption kinetics in the Hanford sediment that contained complex sorbed U(VI) species in mass transfer limited domains. The model was modified and supplemented by including multi-rate, ion exchange reactions to describe the geochemical interactions between the solutions and sediment. With the same set of model parameters, the modified model reasonably well described the evolution of major ions and the rates of U(VI) desorption under variable geochemical and flow conditions, implying that the multi-rate SCM is an effective way to describe U(VI) desorption kinetics in subsurface sediments

Characterization of Cr(VI) removal from aqueous solutions by a surplus agricultural waste-Rice straw

International Nuclear Information System (INIS)

Gao Hui; Liu Yunguo; Zeng Guangming; Xu Weihua; Li Ting; Xia Wenbin

2008-01-01

The removal of Cr(VI) from aqueous solution by rice straw, a surplus agricultural byproduct was investigated. The optimal pH was 2.0 and Cr(VI) removal rate increased with decreased Cr(VI) concentration and with increased temperature. Decrease in straw particle size led to an increase in Cr(VI) removal. Equilibrium was achieved in about 48 h under standard conditions, and Cr(III), which appeared in the solution and remained stable thereafter, indicating that both reduction and adsorption played a part in the Cr(VI) removal. The increase of the solution pH suggested that protons were needed for the Cr(VI) removal. A relatively high level of NO 3 - notably restrained the reduction of Cr(VI) to Cr(III), while high level of SO 4 2- supported it. The promotion of the tartaric acid modified rice straw (TARS) and the slight inhibition of the esterified rice straw (ERS) on Cr(VI) removal indicated that carboxyl groups present on the biomass played an important role in chromium remediation even though were not fully responsible for it. Isotherm tests showed that equilibrium sorption data were better represented by Langmuir model and the sorption capacity of rice straw was found to be 3.15 mg/g

Study of Cr(VI) adsorption onto magnetite nanoparticles using synchrotron-based X-ray absorption spectroscopy

Science.gov (United States)

Chen, Yen-Hua; Liu, Dian-Yu; Lee, Jyh-Fu

2018-04-01

In this study, the efficiency of Cr(VI) adsorption onto nano-magnetite was examined by batch experiments, and the Cr(VI) adsorption mechanism was investigated using synchrotron-based X-ray absorption spectroscopy. Magnetite nanoparticles with a mean diameter of 10 nm were synthesized using an inexpensive and simple co-precipitation method. It shows a saturation magnetization of 54.3 emu/g, which can be recovered with an external magnetic field. The adsorption data fitted the Langmuir adsorption isotherm well, implying a monolayer adsorption behavior of Cr(VI) onto nano-magnetite. X-ray absorption spectroscopy results indicate that the adsorption mechanism involves electron transfer between Fe(II) in nano-magnetite (Fe2+OFe3+ 2O3) and Cr(VI) to transform into Cr(III), which may exist as an Fe(III)-Cr(III) mixed solid phase. Moreover, the Cr(III)/Cr(VI) ratio in the final products can be determined by the characteristic pre-edge peak area of Cr(VI) in the Cr K-edge spectrum. These findings suggest that nano-magnetite is effective for Cr(VI) removal from wastewater because it can transform highly poisonous Cr(VI) species into nontoxic Cr(III) compounds, which are highly insoluble and immobile under environmental conditions.

Adsorption isotherm studies of chromium (VI) from aqueous solutions using sol-gel hydrotalcite-like compounds

Energy Technology Data Exchange (ETDEWEB)

Ramos-Ramirez, Esthela, E-mail: ramosre@quijote.ugto.mx [Centro de Investigaciones en Quimica Inorganica de la Universidad de Guanajuato, Noria Alta s/n, Col. Noria Alta, C.P. 36050, Guanajuato, Gto. (Mexico); Gutierrez Ortega, Norma L.; Conteras Soto, Cesar A. [Centro de Investigaciones en Quimica Inorganica de la Universidad de Guanajuato, Noria Alta s/n, Col. Noria Alta, C.P. 36050, Guanajuato, Gto. (Mexico); Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca s/n, km 36.5, La Marquesa, Coyoacan Mexico, C.P. 52750 (Mexico); Olguin Gutierrez, Maria T. [Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca s/n, km 36.5, La Marquesa, Coyoacan Mexico, C.P. 52750 (Mexico)

2009-12-30

In under-developed countries, industries such as paint and pigment manufacturing, leather tanning, chrome plating and textile processing, usually discharge effluents containing Cr(VI) and Cr(III) into municipal sanitary sewers. It has been reported that Cr(VI) acts as a powerful epithelial irritant and as a human carcinogen. In the present work, hydrotalcite-like compounds with a Mg/Al ratio = 2 were synthesized by the sol-gel method. The hydrotalcite-like compounds and their corresponding thermally treated products were characterized by powder X-ray diffraction, infrared spectroscopy and N{sub 2} adsorption. The hydrotalcite-like compounds and the heated solids were used as adsorbents for Cr(VI) in aqueous solutions. Adsorption isotherm studies of Cr(VI) from aqueous solution are described. The adsorbent capacity was determined using the Langmuir, Freundlich and Dubinin-Radushkevich adsorption isotherm models. The Cr(VI) adsorption isotherm data fit best to the Langmuir isotherm model. The maximum Cr(VI) uptake by hydrotalcite and the heated solids was determined using the Langmuir equation and was found to range between 26 and 29 mg Cr(VI)/g adsorbent.

Adsorption isotherm studies of chromium (VI) from aqueous solutions using sol-gel hydrotalcite-like compounds

International Nuclear Information System (INIS)

Ramos-Ramirez, Esthela; Gutierrez Ortega, Norma L.; Conteras Soto, Cesar A.; Olguin Gutierrez, Maria T.

2009-01-01

In under-developed countries, industries such as paint and pigment manufacturing, leather tanning, chrome plating and textile processing, usually discharge effluents containing Cr(VI) and Cr(III) into municipal sanitary sewers. It has been reported that Cr(VI) acts as a powerful epithelial irritant and as a human carcinogen. In the present work, hydrotalcite-like compounds with a Mg/Al ratio = 2 were synthesized by the sol-gel method. The hydrotalcite-like compounds and their corresponding thermally treated products were characterized by powder X-ray diffraction, infrared spectroscopy and N 2 adsorption. The hydrotalcite-like compounds and the heated solids were used as adsorbents for Cr(VI) in aqueous solutions. Adsorption isotherm studies of Cr(VI) from aqueous solution are described. The adsorbent capacity was determined using the Langmuir, Freundlich and Dubinin-Radushkevich adsorption isotherm models. The Cr(VI) adsorption isotherm data fit best to the Langmuir isotherm model. The maximum Cr(VI) uptake by hydrotalcite and the heated solids was determined using the Langmuir equation and was found to range between 26 and 29 mg Cr(VI)/g adsorbent.

Adsorption isotherm studies of chromium (VI) from aqueous solutions using sol-gel hydrotalcite-like compounds.

Science.gov (United States)

Ramos-Ramírez, Esthela; Ortega, Norma L Gutiérrez; Soto, Cesar A Contreras; Gutiérrez, Maria T Olguín

2009-12-30

In under-developed countries, industries such as paint and pigment manufacturing, leather tanning, chrome plating and textile processing, usually discharge effluents containing Cr(VI) and Cr(III) into municipal sanitary sewers. It has been reported that Cr(VI) acts as a powerful epithelial irritant and as a human carcinogen. In the present work, hydrotalcite-like compounds with a Mg/Al ratio=2 were synthesized by the sol-gel method. The hydrotalcite-like compounds and their corresponding thermally treated products were characterized by powder X-ray diffraction, infrared spectroscopy and N(2) adsorption. The hydrotalcite-like compounds and the heated solids were used as adsorbents for Cr(VI) in aqueous solutions. Adsorption isotherm studies of Cr(VI) from aqueous solution are described. The adsorbent capacity was determined using the Langmuir, Freundlich and Dubinin-Radushkevich adsorption isotherm models. The Cr(VI) adsorption isotherm data fit best to the Langmuir isotherm model. The maximum Cr(VI) uptake by hydrotalcite and the heated solids was determined using the Langmuir equation and was found to range between 26 and 29 mg Cr(VI)/g adsorbent.

A kinetic study of biological Cr(VI) reduction in trickling filters with different filter media types

International Nuclear Information System (INIS)

Dermou, E.; Vayenas, D.V.

2007-01-01

Two pilot-scale trickling filters were used in order to estimate Cr(VI) reduction through biological mechanisms in biofilm reactors operated in SBR mode with recirculation using different filter media types, i.e. plastic media and calcitic gravel. The feed concentrations of Cr(VI) examined were about 5, 10, 20, 30, 50 and 100 mg/l, while the concentration of the organic carbon was constant at 400 mg/l, in order to avoid carbon limitations in the bulk liquid. Maximum reduction rates of 4.8 and 4.7 g Cr(VI)/d were observed for feed Cr(VI) concentration of about 5 mg Cr(VI)/l, for the filters with the plastic support material and the gravel media, respectively. The reduction rates were significantly affected by the feed Cr(VI) concentration in both bioreactors. A dual-enzyme kinetic model was used in order to describe Cr(VI) reduction by aerobically grown mixed cultures. Model predictions were found to correspond very closely to experimental quantitative observations of Cr(VI) reduction at both pilot-scale trickling filters used

Aplikasi Penilaian Kinerja Dosen pada Proses Belajar Mengajar Berbasis Web: Studi Kasus di Badan Penjamin Mutu Internal Institut Teknologi Padang

Directory of Open Access Journals (Sweden)

Harison Son

2017-05-01

Full Text Available The lecturer has the main duty of Tridharma of Higher Education, namely education, research and community service. Currently, the assessment of lecturers using questionnaires by students at the Padang Institute of Technology is still ineffective and the data is less valid. With this application, the internal quality assurance agency of Padang Technology Institute will not be bothered to calculate student questionnaire data as much as 2500 people. The results of this application provide a detailed value to the lecturer, in which a lecturer has a low score and in which part a lecturer excels based on the question items. This value will be calculated by the application of each student who has filled the questionnaire. The application will provide information on the value of the whole lecturer and can be the basis to make improvements to the weakness of the lecturer in detail and accurately. This application is designed using PHP programming language and MySql database. Lecturer performance appraisal results can be obtained directly, to determine the highest to lowest score and can also see the results of the overall lecturer's score accessed on the account of each lecturer on the campus information system. Dosen mempunyai tugas pokok tridharma Perguruan Tinggi, yaitu pendidikan, penelitian dan pengabdian kepada masyarakat. Saat ini, penilaian dosen menggunakan kuesioner oleh mahasiswa di Institut Teknologi Padang masih tidak efektif dan datanya kurang valid. Dengan adanya Aplikasi ini badan penjamin mutu internal Institut Teknologi Padang tidak akan direpotkan untuk mengalkulasi data angket mahasiswa sebanyak 2500 orang. Hasil dari aplikasi ini memberikan nilai secara detail kepada dosen, di bagian mana seorang dosen yang mempunyai nilai rendah dan di bagian mana seorang dosen unggul berdasarkan item pertanyaan. Nilai ini akan di kalkulasi oleh aplikasi setiap mahasiswa yang telah mengisi kuesioner dan akan memberikan informasi nilai secara

A Green Microbial Fuel Cell-Based Biosensor for In Situ Chromium (VI) Measurement in Electroplating Wastewater.

Science.gov (United States)

Wu, Li-Chun; Tsai, Teh-Hua; Liu, Man-Hai; Kuo, Jui-Ling; Chang, Yung-Chu; Chung, Ying-Chien

2017-10-27

The extensive use of Cr(VI) in many industries and the disposal of Cr(VI)-containing wastes have resulted in Cr(VI)-induced environmental contamination. Cr(VI) compounds are associated with increased cancer risks; hence, the detection of toxic Cr(VI) compounds is crucial. Various methods have been developed for Cr(VI) measurement, but they are often conducted offsite and cannot provide real-time toxicity monitoring. A microbial fuel cell (MFC) is an eco-friendly and self-sustaining device that has great potential as a biosensor for in situ Cr(VI) measurement, especially for wastewater generated from different electroplating units. In this study, Exiguobacterium aestuarii YC211, a facultatively anaerobic, Cr(VI)-reducing, salt-tolerant, and exoelectrogenic bacterium, was isolated and inoculated into an MFC to evaluate its feasibility as a Cr(VI) biosensor. The Cr(VI) removal efficiency of E. aestuarii YC211 was not affected by the surrounding environment (pH 5-9, 20-35 °C, coexisting ions, and salinity of 0-15 g/L). The maximum power density of the MFC biosensor was 98.3 ± 1.5 mW/m² at 1500 Ω. A good linear relationship ( r ² = 0.997) was observed between the Cr(VI) concentration (2.5-60 mg/L) and the voltage output. The developed MFC biosensor is a simple device that can accurately measure Cr(VI) concentrations in the actual electroplating wastewater that is generated from different electroplating units within 30 min with low deviations (-6.1% to 2.2%). After treating the actual electroplating wastewater with the MFC, the predominant family in the biofilm was found to be Bacillaceae (95.3%) and was further identified as the originally inoculated E. aestuarii YC211 by next generation sequencing (NGS). Thus, the MFC biosensor can measure Cr(VI) concentrations in situ in the effluents from different electroplating units, and it can potentially help in preventing the violation of effluent regulations.

PENGARUH MODEL PEMBELAJARAN SAINS TEKNOLOGI MASYARAKAT (STM TERHADAP KEMAMPUAN PEMECAHAN MASALAH DAN SELF-EFFICACY SISWA

Directory of Open Access Journals (Sweden)

M. Dwipayana

2017-10-01

Full Text Available Penelitian ini bertujuan menganalisis perbedaan kemampuan pemecahan masalah dan self-efficacy siswa antara kelompok siswa yang belajar dengan model pembelajaran Sains Teknologi Masyarakat (STM dibandingkan dengan kelompok siswa yang belajar dengan model pembelajaran langsung (Direct Instruction. Jenis penelitian ini adalah penelitian semu (quasi experiment dengan rancangan pretest-posttest non equivalent control group design Populasi dalam penelitian ini semua siswa kelas VII SMP 2 Singaraja dan sampel sebanyak 75 orang siswa. Data self-efficacy dikumpulkan dengan metode kuisioner dan data kemampuan pemecahan masalah dikumpulkan dengan tes essay. Analisis data yang digunakan dalam penelitian ini adalah Manova. Berdasarkan penelitian yang telah dilakukan didapatkan hasil bahwa terdapat perbedaan kemampuan pemecahan masalah dan self- efficacy siswa antara kelompok siswa yang belajar dengan model pembelajaran STM dibandingkan dengan kelompok siswa yang belajar dengan model pembelajaran langsung (Direct Instruction dengan rata-rata nilai gain score STM lebih unggul dari nilai gain score DI berturut-turut yaitu 0,53>0,48 pada variabel kemampuan pemecahan masalah dan 0,55>0,41 pada variabel self-efficacy. Hasil Uji LSD menunjukan gain score kemampuan pemecahan masalah dan self-efficacy antara kelompok siswa yang belajar dengan model pembelajaran STM lebih baik dibandingkan dengan kelompok siswa yang belajar dengan model pembelajaran langsung (Direct Instruction.

Derivative spectrophotometric determination of trace amounts of Tungsten(VI) in real water samples

International Nuclear Information System (INIS)

Viswanatha, C.; Ramakrishna Reddy, K.; Devanna, N.; Praveen Kumar, M.D.

2012-01-01

2,4-Dimethoxybenzaldehydeisonicotinoylhydrazone (DMBHIH) has been synthesized and characterized with IR, NMR and Mass Spectroscopic methods. A simple and derivative spectrophotometric method has been developed for the determination of trace amounts of W(VI). The reagent forms a yellow coloured water soluble complex with W(VI) in basic medium (pH 8.0). The molar absorptivity and Sandell's sensitivity of coloured species are 3.43 x 10 4 L.mol -1 cm -1 and 0.0049 μg/cm 2 respectively. Beer's law is obeyed in the range 0.4113-6.2138 μg/ml of W(VI) at λ max 394 nm. W(VI) forms 1:1 complex with DMBHIH and stability constant of the complex was 5.22x10 6 . The first and second derivative amplitude was measured at 453 nm and 468 nm. The developed method applied for the determination of W(VI) in alloys and biological samples. (author)

Complex formation between glutamic acid and molybdenum (VI)

International Nuclear Information System (INIS)

Gharib, Farrokh; Khorrami, S.A.; Sharifi, Sasan

1997-01-01

Equilibria of the reaction of molybdenum (VI) with L-glutamic acid have been studied in aqueous solution in the pH range 2.5 to 9.5, using spectrophotometric and optical rotation methods at constant ionic strength (0.15 mol dm -3 sodium perchlorate) and temperature 25 ± 0.1 degC. Our studies have shown that glutamic acid forms a mononuclear complex with Mo(VI) of the type MoO 3 L 2- at pH 5.5. The stability constant of this complexation and the dissociation constants of L-glutamic acid have been determined. (author). 17 refs., 2 figs., 4 tabs

Thermophysical Properties of Selected II-VI Semiconducting Melts

Science.gov (United States)

Li, C.; Su, Ching-Hua; Lehoczky, S. L.; Scripa, R. N.; Ban, H.; Lin, B.

2004-01-01

Thermophysical properties are essential for the accurate predication of the crystal growth process by computational modeling. Currently, the temperature dependent thermophysical property data for the II-VI semiconductor melts are scarce. This paper reports the results of the temperature dependence of melt density, viscosity and electrical conductivity of selected II-VI compounds, including HgTe, HgCdTe and HgZnTe. The melt density was measured using a pycnometric method, and the viscosity and electrical conductivity were measured by a transient torque method. The results were compared with and showed good agreement with the existing data in the literature.

Analisis Kinerja Sistem Informasi dan Teknologi Informasi untuk Menunjang Kinerja Karyawan Menggunakan Framework IT Balanced Scorecard (Studi Kasus pada Wi-Fi Universitas Kristen Satya Wacana

Directory of Open Access Journals (Sweden)

Bertho Molly

2017-12-01

Wi-Fi UKSW merupakan fasilitas jaringan internet yang dibangun untuk memfasilitasi dan mendukung kebutuhan civitas UKSW dalam proses belajar mengajar. Tujuan penelitian ini adalah melakukan pengukuran bagaimana tingkat pemanfaatan Sistem Informasi dan Teknologi Informasi berdasarkan kinerja karyawan Wi-Fi UKSW. Penelitian ini menggunakan metode IT Balanced Scorecard sebagai sarana pengukuran yang jelas, memantau dan mengoptimalkan realisasi dari nilai atau manfaat bisnis dan manfaat Teknologi Informasi dimana IT Balanced Scorecard mempunyai 4 perspektif (Perspektif Kontribusi Perusahaan, Perspektif Orientasi Pengguna, Perspektif Penyempurnaan Operasional, dan Perspektif Orientasi Masa Depan. Penelitian ini dimulai dari tahapan perencanaan, tahapan studi kelayakan awal dan studi literature, tahapan wawancara dan observasi, tahapan analisis data, serta tahapan membuat dan menyusun laporan serta rekomendasi menggunakan IT Balanced Scorecard. Adapun beberapa hal yang ditemukan dalam penelitian ini dan harus ditangani yaitu, dibutuhkannya penambahan Sumber Daya Manusia (SDM untuk membantu kinerja Wi-Fi UKSW baik dalam hal penanganan complain maupun penyelesaian proyek mengingat Wi-Fi UKSW selalu dibutuhkan dan digunakan oleh semua civitas UKSW serta perlu adanya evaluasi dan upgrade terhadap sistem aplikasi monitoring Wi-Fi. Karena sebagai sarana penyedia layanan jaringan internet yang mana semua yang dilakukan karyawan Wi-Fi UKSW berhubungan erat dengan Sistem Informasi dan Teknologi Informasi dan hasilnya, yang kehadirannya memberikan nilai manfaat yang baik khususnya bagi kemajuan kinerja karyawan Wi-Fi UKSW. Kata kunci: Kinerja SI dan TI, IT Balanced Scorecard, Wi-Fi UKSW Abstract Wi-Fi SWCU is an internet network facility built to facilitate and support the needs of SWCU civities in teaching and learning. The purpose of this research is take measurements of what is the level the use of Information Systems and Information Technology based on of employee performance

Thermodynamic parameters and sorption of U(VI) on ACSD

International Nuclear Information System (INIS)

Donat, R.; Cilgi, G.K.; Cetisli, H.; Aytas, S.

2009-01-01

This paper discusses the sorption properties for U(VI) by alginate coated CaSO 4 x 2H 2 O sepiolite and calcined diatomite earth (Kieselguhr) (ACSD). The removal of U(VI) from aqueous solution by sorption onto ACSF in a single component system with various contact times, pH, temperatures, and initial concentrations of U(VI) was investigated. The sorption patterns of uranium on the composite adsorbent followed the Langmuir, Freundlich and Dubinin-Radushkhevic (D-R) isotherms. The Freundlich, Langmuir, and D-R models have been applied and the data correlated well with Freundlich model and that the sorption was physical in nature (sorption energy, E a = 17.05 kJ/mol). The thermodynamic parameters such as variation of enthalpy ΔH, variation of entropy ΔS and variation of Gibbs free energy ΔG were calculated from the slope and intercept of lnK 0 vs. 1/T plots. Thermodynamic parameters (ΔH ads = 31.83 kJ/mol, ΔS ads = 167 J/mol x K, ΔGdeg ads (293.15 K) = -17.94 kJ/mol) showed the endothermic heat of sorption and the feasibility of the process. The thermodynamics of U(VI) ion/ACSD system indicates the spontaneous and endothermic nature of the process. It was noted that an increase in temperature resulted in a higher uranium loading per unit weight of the adsorbent. (author)

Adsorption behavior and mechanism of Cr(VI) using Sakura waste from aqueous solution

International Nuclear Information System (INIS)

Qi, Wenfang; Zhao, Yingxin; Zheng, Xinyi; Ji, Min; Zhang, Zhenya

2016-01-01

Graphical abstract: The main chemical components of Sakura leaves are cellulose 16.6%, hemicellulose 10.4%, lignin 18.3%, ash 11.4%, and others 43.3%. The adsorption capacity of Cr(VI) onto Sakura leaves can achieve 435.25 mg g"−"1, much higher than other similar agroforestry wastes. - Highlights: • Sakura leaves were prepared to remove Cr(VI) from aqueous solution. • The maximum adsorption capacity of Cr(VI) reached 435.25 mg g"−"1. • Cr(VI) adsorption fitted pseudo-second-order kinetic model. • Isotherm models indicated Cr(VI) adsorption occurred on a monolayer surface. • The influence order of coexisting ions followed PO_4"3"− > SO_4"2"− > Cl"−. - Abstract: A forestall waste, Sakura leave, has been studied for the adsorption of Cr(VI) from aqueous solution. The materials before and after adsorption were characterized by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). To investigate the adsorption performance of Sakura waste, batch experiments were conducted under different adsorbent dosage, contact time, initial concentration of Cr(VI), and co-existing ions. Results showed the data fitted pseudo-second-order better than pseudo-first-order kinetic model. Equilibrium data was analyzed with Langmuir, Freundlich and Redlich–Peterson isotherm models at temperature ranges from 25 °C to 45 °C. The maximum adsorption capacity from the Langmuir model was 435.25 mg g"−"1 at pH 1.0. The presence of Cl"−, SO_4"2"− and PO_4"3"− would lead to an obvious negative effect on Cr(VI) adsorption, and their influence order follows PO_4"3"− > SO_4"2"− > Cl"−. The study developed a new way to reutilize wastes and showed a great potential for resource recycling.

Study on the DNA-protein crosslinks induced by chromium (VI) in SPC-A1

Science.gov (United States)

Liu, Yanqun; Ding, Jianjun; Lu, Xiongbing; You, Hao

2018-01-01

Objective: This study was designed to investigate the effect of chromium (VI) on DNA-protein crosslinks (DPC) of SPC-A1 cells. Methods: We exposed SPC-A1 cells were cultured in 1640 medium and treated with the SPC-A1 cells in vitro to different concentrations of Hexavalent chromium Cr(VI) for 2h, the KC1-SDS precipitation assay were used to measure the DNA-protein cross-linking effect. Results: All the different concentrations of Cr(VI) could cause the increase of DPC coefficient in SPC-A1 cells. But this effect was not significant (P>0.05) at low concentrations; while in high concentration Cr(VI) induced SPC-A1 cells could produce DNA-protein cross-linking effect significantly (P<0.05). Conclusions: chromium (VI) could induce DNA-protein crosslink.

AR4VI: AR as an Accessibility Tool for People with Visual Impairments.

Science.gov (United States)

Coughlan, James M; Miele, Joshua

2017-10-01

Although AR technology has been largely dominated by visual media, a number of AR tools using both visual and auditory feedback have been developed specifically to assist people with low vision or blindness - an application domain that we term Augmented Reality for Visual Impairment (AR4VI). We describe two AR4VI tools developed at Smith-Kettlewell, as well as a number of pre-existing examples. We emphasize that AR4VI is a powerful tool with the potential to remove or significantly reduce a range of accessibility barriers. Rather than being restricted to use by people with visual impairments, AR4VI is a compelling universal design approach offering benefits for mainstream applications as well.

Inhibition of bone resorption by Tanshinone VI isolated from Salvia miltiorrhiza Bunge

Directory of Open Access Journals (Sweden)

V. Nicolin

2010-05-01

Full Text Available During the last decade, a more detailed knowledge of molecular mechanisms involved in osteoclastogenesis has driven research efforts in the development and screening of compound libraries of several small molecules that specifically inhibit the pathway involved in the commitment of the osteoclast precursor cells. Natural compounds that suppress osteoclast differentiation may have therapeutic value in treating osteoporosis and other bone erosive diseases such as rheumatoid arthritis or metastasis associated with bone loss. In ongoing investigation into anti-osteoporotic compounds from natural products we have analyzed the effect of Tanshinone VI on osteoclasts differentiation, using a physiologic three-dimensional osteoblast/bone marrow model of cell co-culture. Tanshinone VI is an abietane diterpene extracted from the root of Salvia miltiorrhiza Bunge (Labiatae, a Chinese traditional crude drug, ‘’Tan-Shen’’. Tashinone has been widely used in clinical practice for the prevention of cardiac diseases, arthritis and other inflammation-related disorders based on its pharmacological actions in multiple tissues. Although Tanshinone VI A has been used as a medicinal agent in the treatment of many diseases, its role in osteoclast-related bone diseases remains unknown. We showed previously that Tanshinone VI greatly inhibits osteoclast differentiation and suppresses bone resorption through disruption of the actin ring; subsequently, we intended to examine the precise inhibitory mechanism of Tanshinone VI on osteoclast differentiating factor. This study shows, for the first time, that Tanshinone VI prevents osteoclast differentiation by inhibiting RANKL expression and NFkB induction.

Oxidation of indometacin by ferrate (VI): kinetics, degradation pathways, and toxicity assessment.

Science.gov (United States)

Huang, Junlei; Wang, Yahui; Liu, Guoguang; Chen, Ping; Wang, Fengliang; Ma, Jingshuai; Li, Fuhua; Liu, Haijin; Lv, Wenying

2017-04-01

The oxidation of indometacin (IDM) by ferrate(VI) (Fe(VI)) was investigated to determine the reaction kinetics, transformation products, and changes in toxicity. The reaction between IDM and Fe(VI) followed first-order kinetics with respect to each reactant. The apparent second-order rate constants (k app ) decreased from 9.35 to 6.52 M -1  s -1 , as the pH of the solution increased from 7.0 to 10.0. The pH dependence of k app might be well explained by considering the species-specific rate constants of the reactions of IDM with Fe(VI). Detailed product studies using liquid chromatography-tandem mass spectrometry (LC-MS/MS) indicated that the oxidation products were primarily derived from the hydrolysis of amide linkages, the addition of hydroxyl groups, and electrophilic oxidation. The toxicity of the oxidation products was evaluated using the Microtox test, which indicated that transformation products exhibited less toxicity to the Vibrio fischeri bacteria. Quantitative structure-activity relationship (QSAR) analysis calculated by the ecological structure activity relationship (ECOSAR) revealed that all of the identified products exhibited lower acute and chronic toxicity than the parent pharmaceutical for fish, daphnid, and green algae. Furthermore, Fe(VI) was effective in the degradation IDM in water containing carbonate ions or fulvic acid (FA), and in lake water samples; however, higher Fe(VI) dosages would be required to completely remove IDM in lake water in contrast to deionized water.

Liquid-liquid extraction and separation studies of uranium(VI)

International Nuclear Information System (INIS)

Langade, A.D.; Shinde, V.M.

1980-01-01

Separation of uranium(VI) from iron(III), molybdenum(VI), vanadium(V), bismuth(III), zirconium(IV) and thorium(IV) is achieved by liquid-liquid extraction with 4-methyl-3-pentene-2-one (mesityl oxide; MeO) from sodium salicylate media (0.1M, pH 6.0). The extracted species is UO 2 (HO.C 6 H 4 COO) 2 .2MeO. A procedure for separating 50 μg of uranium from mg amounts of the other metals is described. (author)

Vi mangler endnu et panel

DEFF Research Database (Denmark)

Ritter, Thomas

2016-01-01

Vi mangler højtuddannede værdiskabere, som transformerer gode idéer og teknologier til indtjening og velstand. Først i mødet med markedet afgøres fremtiden. Troels Lund Poulsen bør nedsætte et kommercialiseringspanel, der byder ind med løsninger, hvordan Danmark bliver et land ikke kun med gode...

Spectrophotometric study of the complexation equilibria of uranium(VI) with 1,4-bis(4'-methylanilino)anthraquinone and determination of uranium(VI)

International Nuclear Information System (INIS)

Idriss, K.A.; Seleim, M.M.; Abu-Bakr, M.S.; Sedaira, H.

1985-01-01

The reaction of U(VI) with 1,4-bis(4'-methylanilino)anthraquinone (quinizarin green) in water-dimethylformamide medium was investigated spectrophotometrically. The complexation equilibria in solution were demonstrated. The study of the reaction in presence of equimolar concentrations or in solutions containing metal or ligand excess gave evidence for the formation of complexes with stoichiometric ratios of UO 2 :L = 1:1 and 1:2 in dependence on the pH of the medium. Their thermodynamic stabilities and the values of their molar absorption coefficients were determined. The optimum conditions for spectrophotometric determination of U(VI) with this reagent were found. (author)

Influence of radiolytic products on the chemistry of uranium VI in brines

International Nuclear Information System (INIS)

Lucchini, J-F.; Reed, D.T.; Borkowski, M.; Rafalski, A.; Conca, J.

2004-01-01

In the near field of a salt repository of nuclear waste, ionizing radiations can strongly affect the chemistry of concentrated saline solutions. Radiolysis can locally modify the redox conditions, speciation, solubility and mobility of the actinide compounds. In the case of uranium VI, radiolytic products can not only reduce U(VI), but also react with uranium species. The net effect on the speciation of uranyl depends on the relative kinetics of the reactions and the buildup of molecular products in brine solutions. The most important molecular products in brines are expected to be hypochlorite ion, hypochlorous acid and hydrogen peroxide. Although U(VI) is expected not to be significantly affected by radiolysis, the combined effects of the major molecular radiolytic products on the chemistry of U(VI) in brines have not been experimentally established previously. (authors)

Unconstrained steps of myosin VI appear longest among known molecular motors.

Science.gov (United States)

Ali, M Yusuf; Homma, Kazuaki; Iwane, Atsuko Hikikoshi; Adachi, Kengo; Itoh, Hiroyasu; Kinosita, Kazuhiko; Yanagida, Toshio; Ikebe, Mitsuo

2004-06-01

Myosin VI is a two-headed molecular motor that moves along an actin filament in the direction opposite to most other myosins. Previously, a single myosin VI molecule has been shown to proceed with steps that are large compared to its neck size: either it walks by somehow extending its neck or one head slides along actin for a long distance before the other head lands. To inquire into these and other possible mechanism of motility, we suspended an actin filament between two plastic beads, and let a single myosin VI molecule carrying a bead duplex move along the actin. This configuration, unlike previous studies, allows unconstrained rotation of myosin VI around the right-handed double helix of actin. Myosin VI moved almost straight or as a right-handed spiral with a pitch of several micrometers, indicating that the molecule walks with strides slightly longer than the actin helical repeat of 36 nm. The large steps without much rotation suggest kinesin-type walking with extended and flexible necks, but how to move forward with flexible necks, even under a backward load, is not clear. As an answer, we propose that a conformational change in the lifted head would facilitate landing on a forward, rather than backward, site. This mechanism may underlie stepping of all two-headed molecular motors including kinesin and myosin V.

Influence of chemical compositions and molecular weights of humic acids on Cr(VI) photo-reduction

Energy Technology Data Exchange (ETDEWEB)

Chen, S.Y.; Huang, S.W. [Department of Soil and Environmental Sciences, National Chung Hsing University, Taichung, 40227 Taiwan, ROC (China); Chiang, P.N. [The Experimental Forest, National Taiwan University, Nantou, 55743 Taiwan, ROC (China); Liu, J.C. [Agricultural Research Institute No. 189, Jhongjheng Rd., Wufong, Taichung County, 41301 Taiwan, ROC (China); Kuan, W.H. [Department of Safety, Health, and Environmental Engineering, Ming Chi University of Technology, Taishan, Taipei, 24301 Taiwan, ROC (China); Huang, J.H. [Department of Soil and Environmental Sciences, National Chung Hsing University, Taichung, 40227 Taiwan, ROC (China); Hung, J.T. [Department of Horticulture, National Taitung Junior College, Taitung, 95045 Taiwan, ROC (China); Tzou, Y.M., E-mail: ymtzou@dragon.nchu.edu.tw [Department of Soil and Environmental Sciences, National Chung Hsing University, Taichung, 40227 Taiwan, ROC (China); Chen, C.C. [Department of Life Science, National Taiwan Normal University, Taipei, 116 Taiwan, ROC (China); Wang, M.K. [Department of Agricultural Chemistry, National Taiwan University, Taipei, 10617 Taiwan, ROC (China)

2011-12-15

Highlights: Black-Right-Pointing-Pointer Low molecular weights (M{sub w}) of HA bear more polar and aromatic C in its structure. Black-Right-Pointing-Pointer The polar sites of HA dominate the photo-reduction of Cr(VI). Black-Right-Pointing-Pointer Low M{sub w} of HA exhibits greater photochemical efficiency for Cr(VI) reduction. Black-Right-Pointing-Pointer Cr(VI) adsorption on HA is indiscernible, particularly on the small M{sub w} of HA. Black-Right-Pointing-Pointer Upon Cr(VI) reduction by HA, most of Cr(III) are released into the solution. - Abstract: Humic acids (HA) strongly affect the fate of trace metals in soils and aquatic environments. One of the remarkable properties of HA is its ability to reduce Cr(VI), an extremely toxic anion. However, it is unclear which HA components are involved in Cr(VI) reduction and possess the photo-induced properties. In this study, an ultrafiltration technique was used to fractionate HAs into four fractions of different nominal molecular weights (M{sub w}): >100, 50-100, 10-50 and <10 kDa. Each HA fraction was characterized by spectroscopic analyses followed by examining Cr(VI) removal on each fraction of HA at pH 1-5. Spectroscopic results indicated that low-M{sub w} HA was enriched with polar and aromatic domains. These polar, including polar C in aliphatic region, and aromatic groups were the major sites for Cr(VI) reduction because they disappeared rapidly upon interaction with Cr(VI). As a result, low M{sub w} of HA exhibited greater efficiency of Cr(VI) reduction. Light induced the rapid transfer of electrons between chromate-phenol/carboxyl ester, or the formation of peroxide radicals or H{sub 2}O{sub 2} through the ready decay of peroxy radicals associated with polar substituents, explained the rapid scavenging of Cr(VI) on polar and aromatic groups of HAs under illumination.

Summary of the planning, management, and evaluation process for the Geothermal Program Review VI conference

Energy Technology Data Exchange (ETDEWEB)

1988-10-01

The purpose of this document is to present an overview of the planning, facilitation, and evaluation process used to conduct the Geothermal Program Review VI (PR VI) conference. This document was also prepared to highlight lessons learned from PR VI and, by utilizing the evaluation summaries and recommendations, be used as a planning tool for PR VII. The conference, entitled Beyond Goals and Objectives,'' was sponsored by the US Department of Energy's (DOE) Geothermal Technology Division (GTD), PR VI was held in San Francisco, California on April 19--21, 1988 and was attended by 127 participants. PR VI was held in conjunction with the National Geothermal Association's (NGA) Industry Round Table. This document presents a brief summary of the activities, responsibilities, and resources for implementing the PR VI meeting and provides recommendations, checklists, and a proposed schedule for assisting in planning PR VII.

Hvad skal vi med Etisk Råd?

DEFF Research Database (Denmark)

Ploug, Thomas; Gjerris, Mickey

2012-01-01

Det Etiske Råd har for os at se en væsentlig rolle at spille i et åbent og demokratisk samfund som det danske. Vi skal være med til at skabe grobund for de værdidiskussioner, som skal forme fremtidens samfund. Etik er at være i dialog – ikke at kaste med mudder.......Det Etiske Råd har for os at se en væsentlig rolle at spille i et åbent og demokratisk samfund som det danske. Vi skal være med til at skabe grobund for de værdidiskussioner, som skal forme fremtidens samfund. Etik er at være i dialog – ikke at kaste med mudder....

Chromium(VI) sorption efficiency of acid-activated banana peel over organo-montmorillonite in aqueous solutions.

Science.gov (United States)

Ashraf, Anam; Bibi, Irshad; Niazi, Nabeel Khan; Ok, Yong Sik; Murtaza, Ghulam; Shahid, Muhammad; Kunhikrishnan, Anitha; Li, Dongwei; Mahmood, Tariq

2017-07-03

In the present study, we examined sorption of chromate (Cr(VI)) to acid-activated banana peel (AABP) and organo-montmorillonite (O-mont) as a function of pH, initial Cr(VI) concentration at a sorbent dose of 4 g L -1 and at 20 ± 1°C in aqueous solutions. In sorption edge experiments, maximum Cr(VI) removal was obtained at pH 3 after 2 hours by AABP and O-mont (88% and 69%). Sorption isotherm data showed that the sorption capacity of AABP was higher than O-mont (15.1 vs. 6.67 mg g -1 , respectively, at pH 4). Freundlich and Langmuir models provided the best fits to describe Cr(VI) sorption onto AABP (R 2 = 0.97) and O-mont (R 2 = 0.96). Fourier transform infrared spectroscopy elucidated that for AABP mainly the -OH, -COOH, -NH 2 , and for O-mont intercalated amines and -OH surface functional groups were involved in Cr(VI) sorption. The scanning electron microscopy combined with energy dispersive X-ray spectroscopy (SEM-EDX) analyses, although partly, indicate that the (wt. %) proportion of cations (e.g., Ca, Mg) in AABP decreased after Cr(VI) sorption. This may be due to ion exchange of chromite (Cr(III)) (produced from Cr(VI) reduction) with cationic elements in AABP. Also, Cr(VI) desorption (using phosphate solution) from AABP was lower (29%) than that from O-mont (51%) up to the third regeneration cycle. This bench scale comparative study highlights that the utilization of widely available and low-cost acid-activated biomaterials has a greater potential than organo-clays for Cr(VI) removal in aqueous media. However, future studies are warranted to precisely delineate different mechanisms of Cr(VI) sorption/reduction by acid-activated biomaterials and organo-clays.

Designing and implementing a Quality Broker: the GeoViQua experience

Science.gov (United States)

Papeschi, Fabrizio; Bigagli, Lorenzo; Masò, Joan; Nativi, Stefano

2014-05-01

GeoViQua (QUAlity aware VIsualisation for the Global Earth Observation System of Systems) is an FP7 project aiming at complementing the Global Earth Observation System of Systems (GEOSS) with rigorous data quality specifications and quality-aware capabilities, in order to improve reliability in scientific studies and policy decision-making. GeoViQua main scientific and technical objective is to enhance the GEOSS Common Infrastructure (GCI) providing the user community with innovative quality-aware search and visualization tools, which will be integrated in the GEOPortal, as well as made available to other end-user interfaces. To this end, GeoViQua will promote the extension of the current standard metadata for geographic information with accurate and expressive quality indicators. Employing and extending several ISO standards such as 19115, 19157 and 19139, a common set of data quality indicators has been selected to be used within the project. The resulting work, in the form of a data model, is expressed in XML Schema Language and encoded in XML. Quality information can be stated both by data producers and by data users, actually resulting in two conceptually distinct data models, the Producer Quality model and the User Quality model (or User Feedback model). GeoViQua architecture is built on the brokering approach successfully experimented within the EuroGEOSS project and realized by the GEO DAB (Discovery and Access Broker) which is part of the GCI. The GEO DAB allows for harmonization and distribution in a transparent way for both users and data providers. This way, GeoViQua can effectively complement and extend the GEO DAB obtaining a Quality augmentation Broker (DAB-Q) which plays a central role in ensuring the consistency of the Producer and User quality models. The GeoViQua architecture also includes a Feedback Catalog, a particular service brokered by the DAB-Q which is dedicated to the storage and discovery of user feedbacks. A very important issue

Structural and elastic properties of AIBIIIC 2 VI semiconductors

Science.gov (United States)

Kumar, V.; Singh, Bhanu P.

2018-01-01

The plane wave pseudo-potential method within density functional theory has been used to calculate the structural and elastic properties of AIBIIIC 2 VI semiconductors. The electronic band structure, density of states, lattice constants (a and c), internal parameter (u), tetragonal distortion (η), energy gap (Eg), and bond lengths of the A-C (dAC) and B-C (dBC) bonds in AIBIIIC 2 VI semiconductors have been calculated. The values of elastic constants (Cij), bulk modulus (B), shear modulus (G), Young's modulus (Y), Poisson's ratio (υ), Zener anisotropy factor (A), Debye temperature (ϴD) and G/B ratio have also been calculated. The values of all 15 parameters of CuTlS2 and CuTlSe2 compounds, and 8 parameters of 20 compounds of AIBIIIC 2 VI family, except AgInS2 and AgInSe2, have been calculated for the first time. Reasonably good agreement has been obtained between the calculated, reported and available experimental values.

Benchmark analysis of MCNP trademark ENDF/B-VI iron

International Nuclear Information System (INIS)

Court, J.D.; Hendricks, J.S.

1994-12-01

The MCNP ENDF/B-VI iron cross-section data was subjected to four benchmark studies as part of the Hiroshima/Nagasaki dose re-evaluation for the National Academy of Science and the Defense Nuclear Agency. The four benchmark studies were: (1) the iron sphere benchmarks from the Lawrence Livermore Pulsed Spheres; (2) the Oak Ridge National Laboratory Fusion Reactor Shielding Benchmark; (3) a 76-cm diameter iron sphere benchmark done at the University of Illinois; (4) the Oak Ridge National Laboratory Benchmark for Neutron Transport through Iron. MCNP4A was used to model each benchmark and computational results from the ENDF/B-VI iron evaluations were compared to ENDF/B-IV, ENDF/B-V, the MCNP Recommended Data Set (which includes Los Alamos National Laboratory Group T-2 evaluations), and experimental data. The results show that the ENDF/B-VI iron evaluations are as good as, or better than, previous data sets

Treatment of selected pharmaceuticals by ferrate(VI): performance, kinetic studies and identification of oxidation products.

Science.gov (United States)

Zhou, Zhengwei; Jiang, Jia-Qian

2015-03-15

The performance of ferrate(VI) in treating sulfamethoxazole (SMX), diclofenac (DCF), carbamazepine (CBZ) and bezafibrate (BZF) in test solutions containing the four compounds was investigated. A series of jar-test experiments was performed on a bench-scale at pH 6-9 and at a ferrate(VI) dose of 1-5 mg Fe/L. The results suggested that ferrate(VI) can effectively remove SMX, DCF and CBZ from the test solutions, with greater than 80% removal under optimum conditions. However, the removal efficiency of BZF was very low, less than 25% under the studied conditions. Increasing the dose of ferrate(VI) improved the treatment performance, while the influence of solution pH on ferrate(VI) performance varied among the different target compounds. Ferrate(VI) demonstrated the highest reactivity with SMX at pH 8 and pH 9 (20 °C), with apparent second-order rate constants of 360±17 M(-1) s(-1) and 1.26±0.02 M(-1) s(-1), respectively. However, BZF showed the lowest removal by ferrate(VI) with the smallest rate constants (less than 0.5 M(-1) s(-1)) at pH 8 and pH 9. Furthermore, a number of oxidation products (OPs) of SMX, DCF and CBZ during ferrate(VI) oxidation were detected by liquid chromatography and mass spectrometry (LC-MS), and their degradation pathways were tentatively proposed. No OPs of BZF were detected during ferrate(VI) oxidation. Copyright © 2014 Elsevier B.V. All rights reserved.

A coupled mass transfer and surface complexation model for uranium (VI) removal from wastewaters

International Nuclear Information System (INIS)

Lenhart, J.; Figueroa, L.A.; Honeyman, B.D.

1994-01-01

A remediation technique has been developed for removing uranium (VI) from complex contaminated groundwater using flake chitin as a biosorbent in batch and continuous flow configurations. With this system, U(VI) removal efficiency can be predicted using a model that integrates surface complexation models, mass transport limitations and sorption kinetics. This integration allows the reactor model to predict removal efficiencies for complex groundwaters with variable U(VI) concentrations and other constituents. The system has been validated using laboratory-derived kinetic data in batch and CSTR systems to verify the model predictions of U(VI) uptake from simulated contaminated groundwater

The effects of chromium(VI) on the thioredoxin system: Implications for redox regulation

Science.gov (United States)

Myers, Charles R.

2014-01-01

Hexavalent chromium [Cr(VI)] compounds are highly redox active and have long been recognized as potent cytotoxins and carcinogens. The intracellular reduction of Cr(VI) generates reactive Cr intermediates, which are themselves strong oxidants, as well as superoxide, hydrogen peroxide, and hydroxyl radical. These probably contribute to the oxidative damage and effects on redox-sensitive transcription factors that have been reported. However, the identification of events that initiate these signaling changes has been elusive. More recent studies show that Cr(VI) causes irreversible inhibition of thioredoxin reductase (TrxR) and oxidation of thioredoxin (Trx) and peroxiredoxin (Prx). Mitochondrial Trx2/Prx3 are more sensitive to Cr(VI) treatment than cytosolic Trx1/Prx1, although both compartments show thiol oxidation with higher doses or longer treatments. Thiol redox proteomics demonstrate that Trx2, Prx3, and Trx1 are among the most sensitive proteins in cells to Cr(VI) treatment. Their oxidation could therefore represent initiating events that have widespread implications for protein thiol redox control and for multiple aspects of redox signaling. This review summarizes the effects of Cr(VI) on the TrxR/Trx system and how these events could influence a number of downstream redox signaling systems that are influenced by Cr(VI) exposure. Some of the signaling events discussed include the activation of apoptosis signal regulating kinase and MAP kinases (p38 and JNK) and the modulation of a number of redox-sensitive transcription factors including AP-1, NF-κB, p53, and Nrf2. PMID:22542445

Microbial reduction of uranium(VI) in sediments of different lithologies collected from Sellafield

International Nuclear Information System (INIS)

Newsome, Laura; Morris, Katherine; Trivedi, Divyesh; Atherton, Nick; Lloyd, Jonathan R.

2014-01-01

Highlights: • U(VI) (aq) mobility can be controlled by stimulating biogeochemical interactions. • Indigenous microbes in varied sediments reduced U(VI) to insoluble U(IV). • Sediment cell numbers and amount of bioavailable Fe(III) could limit this process. - Abstract: The presence of uranium in groundwater at nuclear sites can be controlled by microbial processes. Here we describe the results from stimulating microbial reduction of U(VI) in sediment samples obtained from a nuclear-licensed site in the UK. A variety of different lithology sediments were selected to represent the heterogeneity of the subsurface at a site underlain by glacial outwash deposits and sandstone. The natural sediment microbial communities were stimulated via the addition of an acetate/lactate electron donor mix and were monitored for changes in geochemistry and molecular ecology. Most sediments facilitated the removal of 12 ppm U(VI) during the onset of Fe(III)-reducing conditions; this was reflected by an increase in the proportion of known Fe(III)- and U(VI)-reducing species. However U(VI) remained in solution in two sediments and Fe(III)-reducing conditions did not develop. Sequential extractions, addition of an Fe(III)-enrichment culture and most probable number enumerations revealed that a lack of bioavailable iron or low cell numbers of Fe(III)-reducing bacteria may be responsible. These results highlight the potential for stimulation of microbial U(VI)-reduction to be used as a bioremediation strategy at UK nuclear sites, and they emphasise the importance of both site-specific and borehole-specific investigations to be completed prior to implementation

Removing uranium (VI) from aqueous solution with insoluble humic acid derived from leonardite.

Science.gov (United States)

Meng, Fande; Yuan, Guodong; Larson, Steven L; Ballard, John H; Waggoner, Charles A; Arslan, Zikri; Han, Fengxiang X

2017-12-01

The occurrence of uranium (U) and depleted uranium (DU)-contaminated wastes from anthropogenic activities is an important environmental problem. Insoluble humic acid derived from leonardite (L-HA) was investigated as a potential adsorbent for immobilizing U in the environment. The effect of initial pH, contact time, U concentration, and temperature on U(VI) adsorption onto L-HA was assessed. The U(VI) adsorption was pH-dependent and achieved equilibrium in 2 h. It could be well described with pseudo-second-order model, indicating that U(VI) adsorption onto L-HA involved chemisorption. The U(VI) adsorption mass increased with increasing temperature with maximum adsorption capacities of 91, 112 and 120 mg g -1 at 298, 308 and 318 K, respectively. The adsorption reaction was spontaneous and endothermic. We explored the processes of U(VI) desorption from the L-HA-U complex through batch desorption experiments in 1 mM NaNO 3 and in artificial seawater. The desorption process could be well described by pseudo-first-order model and reached equilibrium in 3 h. L-HA possessed a high propensity to adsorb U(VI). Once adsorbed, the release of U(VI) from L-HA-U complex was minimal in both 1 mM NaNO 3 and artificial seawater (0.06% and 0.40%, respectively). Being abundant, inexpensive, and safe, L-HA has good potential for use as a U adsorbent from aqueous solution or immobilizing U in soils. Copyright © 2017 Elsevier Ltd. All rights reserved.

Preparation of N-1 -naphthyl benzo- and N-phenyl benzo hydroxamic acids and study of their extractability towards Fe (III), Cr (VI) and U (VI)

Energy Technology Data Exchange (ETDEWEB)

Mohamed, Eltoum Elnour [Department of Chemistry, Faculty of Science, University of Khartoum, Khartoum (Sudan)

1997-12-01

Two aryl hydroxamic acids were prepared; The N-phenyl benzo hydroxamic acid and the N-1- naphthyl benzohydroxamic acid the first one was prepared by the partial reduction of nitrobenzene to the {beta}-phenyl hydroxylamine and coupling the latter with benzyl chloride. The reduction was carried out using ammonium chloride and zinc dust; this pair failed after so many attempts to give the N-1- naphthyl hydroxylamine. So the latter was prepared by using a somewhat milder reducing agent; hydrogen sulphide and ammonia gas in absolute alcohol. The two acids were obtained using the modified procedure of Tandon coupling the hydroxylamine with benzoyl chloride. The two acids were characterized by their melting points, elemental analysis, their I.R functional group frequencies and by their characteristic colour tests with vanadium (VI) and Iron (III). The acids were used for the extraction and spectrophotometric determination for iron (III), Chromium (VI), and Uranium (VI) from different molar solution, PH and from synthetic sea water. The maximum recovery of iron (III) occurred at PH 4 and PH 5 giving 92.25 and 91.25% when using N-1-naphthyl benzo hydroxamic acid and a maximum recovery of 100% at PH 5 with other acid. The maximum recovery of Chromium (VI) occurred at 3MH{sup 2}SO{sup 4} of 97.50% when using N-1-naphthyl benzohydroxamic acid and a maximum of 94.25% at the same molar concentration with N-phenyl benzo hydroxamic acid. The maximum recovery for Uranium (VI) was occurred at PH 7 giving 100% when using N-1-naphthyl benzo hydroxamic acid and a maximum recovery of 85% at PH 7 and PH* with the other acid. The two reagents give sharp colour with both iron (III) and chromium (VI), so trials were carried out to compare the curves obtained with that of the original reagent i.e. Thiocynate and diphenylcarbazide, which give a smaller slope.(Author) 121 refs. , 15 tabs. , 13 figs

Preparation of N-1 -naphthyl benzo- and N-phenyl benzo hydroxamic acids and study of their extractability towards Fe (III), Cr (VI) and U (VI)

International Nuclear Information System (INIS)

Mohamed, Eltoum Elnour

1997-12-01

Two aryl hydroxamic acids were prepared; The N-phenyl benzo hydroxamic acid and the N-1- naphthyl benzohydroxamic acid the first one was prepared by the partial reduction of nitrobenzene to the β-phenyl hydroxylamine and coupling the latter with benzyl chloride. The reduction was carried out using ammonium chloride and zinc dust; this pair failed after so many attempts to give the N-1- naphthyl hydroxylamine. So the latter was prepared by using a somewhat milder reducing agent; hydrogen sulphide and ammonia gas in absolute alcohol. The two acids were obtained using the modified procedure of Tandon coupling the hydroxylamine with benzoyl chloride. The two acids were characterized by their melting points, elemental analysis, their I.R functional group frequencies and by their characteristic colour tests with vanadium (VI) and Iron (III). The acids were used for the extraction and spectrophotometric determination for iron (III), Chromium (VI), and Uranium (VI) from different molar solution, PH and from synthetic sea water. The maximum recovery of iron (III) occurred at PH 4 and PH 5 giving 92.25 and 91.25% when using N-1-naphthyl benzo hydroxamic acid and a maximum recovery of 100% at PH 5 with other acid. The maximum recovery of Chromium (VI) occurred at 3MH 2 SO 4 of 97.50% when using N-1-naphthyl benzohydroxamic acid and a maximum of 94.25% at the same molar concentration with N-phenyl benzo hydroxamic acid. The maximum recovery for Uranium (VI) was occurred at PH 7 giving 100% when using N-1-naphthyl benzo hydroxamic acid and a maximum recovery of 85% at PH 7 and PH* with the other acid. The two reagents give sharp colour with both iron (III) and chromium (VI), so trials were carried out to compare the curves obtained with that of the original reagent i.e. Thiocynate and diphenylcarbazide, which give a smaller slope.(Author)

A conserved aromatic lock for the tryptophan rotameric switch in TM-VI of seven-transmembrane receptors

DEFF Research Database (Denmark)

Holst, Birgitte; Nygaard, Rie; Hansen, Louise Valentin

2010-01-01

simulations in rhodopsin demonstrated that rotation around the chi1 torsion angle of Trp-VI:13 brings its side chain close to the equally highly conserved Phe-V:13 (Phe-5.47) in TM-V. In the ghrelin receptor, engineering of high affinity metal-ion sites between these positions confirmed their close spatial...... degree as observed in the constructs where Trp-VI:13 itself was mutated, but again without affecting agonist potency. In a proposed active receptor conformation generated by molecular simulations, where the extracellular segment of TM-VI is tilted inwards in the main ligand-binding pocket, Trp-VI:13......The conserved tryptophan in position 13 of TM-VI (Trp-VI:13 or Trp-6.48) of the CWXP motif located at the bottom of the main ligand-binding pocket in TM-VI is believed to function as a rotameric microswitch in the activation process of seven-transmembrane (7TM) receptors. Molecular dynamics...

Removal of Cr(VI) by nanoscale zero-valent iron (nZVI) from soil contaminated with tannery wastes.

Science.gov (United States)

Singh, Ritu; Misra, Virendra; Singh, Rana Pratap

2012-02-01

The illegal disposal of tannery wastes at Rania, Kanpur has resulted in accumulation of hexavalent chromium [Cr(VI)], a toxic heavy metal in soil posing risk to human health and environment. 27 soil samples were collected at various depths from Rania for the assessment of Cr(VI) level in soil. Out of 27 samples, five samples had shown significant level of Cr(VI) with an average concentration of 15.84 mg Kg(-1). Varied doses of nanoscale zero-valent iron (nZVI) were applied on Cr(VI) containing soil samples for remediation of Cr(VI). Results showed that 0.10 g L(-1) nZVI completely reduces Cr(VI) within 120 min following pseudo first order kinetics. Further, to test the efficacy of nZVI in field, soil windrow experiments were performed at the contaminated site. nZVI showed significant Cr(VI) reduction at field also, indicating it an effective tool for managing sites contaminated with Cr(VI).

77 FR 16251 - Announcement of Funding Awards, HOPE VI Revitalization Grant Program, Fiscal Year 2010

Science.gov (United States)

2012-03-20

... Awards, HOPE VI Revitalization Grant Program, Fiscal Year 2010 AGENCY: Office of the Assistant Secretary... the Fiscal Year 2010 (FY2010) Notice of Funding Availability (NOFA) for the HOPE VI Revitalization... recipients under the HOPE VI Revitalization grant program. FOR FURTHER INFORMATION CONTACT: For questions...

Removal of chromium (VI) from electroplating wastewater using an anion exchanger derived from rice straw.

Science.gov (United States)

Cao, Wei; Dang, Zhi; Yia, Xiao-Yun; Yang, Chen; Lu, Gui-Ning; Liu, Yun-Feng; Huang, Se-Yan; Zheng, Liu-Chun

2013-01-01

An anion exchanger from rice straw was used to remove Cr (VI) from synthetic wastewater and electroplating effluent. The exchanger was characterized using Fourier transform infrared (FTIR) spectrum and scanning electron microscopy (SEM), and it was found that the quaternary amino group and hydroxyl group are the main functional groups on the fibrous surface of the exchanger. The effect of contact time, initial concentration and pH on the removal of Cr (VI), and adsorption isotherms at different temperature, was investigated. The results showed that the removal of Cr (VI) was very rapid and was significantly affected by the initial pH of the solution. Although acidic conditions (pH = 2-6) facilitated Cr (VI) adsorption, the exchanger was effective in neutral solution and even under weak base conditions. The equilibrium data fitted well with Langmuir adsorption model, and the maximum Cr (VI) adsorption capacities at pH 6.4 were 0.35, 0.36 and 0.38 mmol/g for 15, 25 and 35 degrees C, respectively. The exchanger was finally tested with real electroplating wastewater, and at sorbent dosage of 10 g/L, the removal efficiencies for Cr (VI) and total Cr were 99.4% and 97.8%, respectively. In addition, the positive relationship between adsorbed Cr (VI) and desorbed Cl- suggested that Cr (VI) was mainly removed by ion exchange with chlorine.

Comparative EXAFS study of uranium(VI) and neptunium(V) sorption onto kaolinite

International Nuclear Information System (INIS)

Reich, T.; Amayri, S.; Reich, Ta.; Jermolajev, J.

2005-01-01

Full text of publication follows: We investigated the surface sorption process of U(VI) and Np(V) on kaolinite by extended X-ray absorption fine structure (EXAFS) spectroscopy in the 10 μM concentration range. Batch experiments with kaolinite in CO 2 -equilibrated systems showed that the adsorption edge of U(VI) occurs at pH 5.5, i.e., near the pH PZC of kaolinite. The adsorption edge of Np(V) occurs well above the pH PZC value at pH 8.5. This may indicate that the bonds between Np(V) and the surface functional groups of kaolinite are not as strong as in the case of U(VI). U(VI) and Np(V) have in common that the amount which is adsorbed decreases when the pH is increased beyond the absorption maximum. This behavior can be attributed to the formation of U(VI) and Np(V) carbonato complexes in the aqueous solutions. The aim of this comparative EXAFS study was to investigate the reason for the different affinities of U(VI) and Np(V) for kaolinite by measuring their local environments at the clay surface. Samples were prepared from 4 g/L kaolinite, 0.1 M NaClO 4 , pH 3.0 - 10.5, presence and absence of ambient CO 2 . The U L 3 - and Np L 2 -edge EXAFS spectra of the wet paste samples were measured at room temperature in fluorescence mode at the Rossendorf Beamline (ROBL) at the European Synchrotron Radiation Facility. The measured U-O and U-Al/Si distances indicate inner-sphere sorption of U(VI) on kaolinite. There was no evidence of uranium neighbors in the EXAFS spectra, suggesting that the adsorbed U(VI) complexes were predominantly monomeric. The average distance between uranium and its equatorial oxygen atoms, O eq , increased from 2.32 to 2.38 Angstrom in the presence of atmospheric CO 2 when the pH was increased from 5.0 to 8.5. In the CO 2 -free system, the U-O eq distance was independent from pH and equal to 2.32 Angstrom. The lengthening of the average U-O eq distance in the presence of carbonate (or bicarbonate) suggests the formation of ternary U(VI

Collagen VI disorders: Insights on form and function in the extracellular matrix and beyond.

Science.gov (United States)

Lamandé, Shireen R; Bateman, John F

2017-12-22

Mutations in the three canonical collagen VI genes, COL6A1, COL6A2 and COL6A3, cause a spectrum of muscle disease from Bethlem myopathy at the mild end to the severe Ullrich congenital muscular dystrophy. Mutations can be either dominant or recessive and the resulting clinical severity is influenced by the way mutations impact the complex collagen VI assembly process. Most mutations are found towards the N-terminus of the triple helical collagenous domain and compromise extracellular microfibril assembly. Outside the triple helix collagen VI is highly polymorphic and discriminating mutations from rare benign changes remains a major diagnostic challenge. Collagen VI deficiency alters extracellular matrix structure and biomechanical properties and leads to increased apoptosis and oxidative stress, decreased autophagy, and impaired muscle regeneration. Therapies that target these downstream consequences have been tested in a collagen VI null mouse and also in small human trials where they show modest clinical efficacy. An important role for collagen VI in obesity, cancer and diabetes is emerging. A major barrier to developing effective therapies is the paucity of information about how collagen VI deficiency in the extracellular matrix signals the final downstream consequences - the receptors involved and the intracellular messengers await further characterization. Copyright © 2017 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.

Energy balance of ENDF/B-VI

International Nuclear Information System (INIS)

MacFarlane, R.E.

1994-01-01

ENDF/B-VI through Release 2 has been tested for neutron-photon energy balance using the Heater module of the NJOY nuclear data procesing system. The situation is much improved over ENDF/B-V, but there are still a number of maerials that show problems

Some organodioxygen complexes of molybdenum(VI), tungsten(VI), zinc(II) and cadmium(II) containing some monodentate and multidentate ligands

International Nuclear Information System (INIS)

Tarafder, M.T.H.; Leo Man Lin; Grouse, Karen A.; Mariotto, Gino

2003-08-01

Several novel organodioxygen complexes of the type [M(O)(O 2 ) 2 L](MMo(VI), W(VI)) and [M'(O 2 )L](M'= Cd(II) and Zn(II)) have been synthesized using monodentate, bidentate and tridentate ligands, L pyridine, picolinic acid, diethylenetriamine, 1,2-phenylenediamine, triphenylphosphine oxide. These complexes were characterized by elemental analyses, conductivity measurements, infrared, Raman spectral studies. For dioxygen complexes, the v(O=O) stretches of the superoxo moities were only Raman active, because of apparent linearity of the M-O 2 moieties, giving peaks at 1020-1030 cm -1 . The complexes were all thermodynamically stable. The dioxygen complexes containing bidentate co-ligands were found to show oxygen transfer reactions to various organic and inorganic substrates. Mechanisms have been postulated. (author)

Cr(III) and Cr(VI) in leather and elicitation of eczema

DEFF Research Database (Denmark)

Hansen, Malene Barré; Menne, Torkil; Johansen, Jeanne Duus

2006-01-01

The aim of the present study was to investigate the relation between the content of Cr(VI) and soluble Cr(III) in leather and the ability of the leather to elicit eczema in chromium allergic patients. An array of chromium-tanned leather samples was analysed for the content of total Cr(VI) and sol...

Biosorption of Cr(VI from Aqueous Solution Using Murraya koenigii (Curry tree Stems

Directory of Open Access Journals (Sweden)

Selvaraj Suresh

2016-12-01

Full Text Available In the present work, the sorption capacity of Murraya Koenigii Stems (MKST, an agricultural waste, is identified for the removal of Cr(VI from aqueous solution and the effect of different process parameters likes pH and adsorbent dosage were studied. pH 1 is observed to be the optimum pH for Cr(VI sorption onto the biosorbent. The equilibrium data of Cr(VI sorption fit well with the Langmuir model with a monolayer sorption capacity of 12.25 mg/g. The results show that the metal ion interacts strongly with the biosorbent and can be effectively used in the removal of Cr(VI from aqueous solution. DOI: http://dx.doi.org/10.17807/orbital.v0i0.867

Adsorción de Cr VI sobre residuos de café

Directory of Open Access Journals (Sweden)

Pablo Cubides Guerrero

2014-12-01

Full Text Available En el presente trabajo se estudió el proceso de adsorción de cromo VI en 3 diferentes adsorbentes; carbón activado comercial, carbón activado preparado a partir de residuos de café y los residuos de café. De estos se eligió el residuo de café (cuncho, como la mejor alternativa entre las analizadas, para este propósito se trabajó como modelo de estudio, soluciones acuosas de dicromato de potasio en concentraciones de 5μg/ml (expresada como cromo VI y diferentes dosificaciones de residuo de café; la concentración de cromo VI se analizó por espectrofotometría a 540 nm y la de cromo total se realizó por absorción atómica, para este proceso se analizaron las isotermas de adsorción y se determinó que el proceso se adapta al modelo de Freundlich, la cinética de la adsorción es de segundo orden y se llegaron a obtener adsorciones superiores al 95% de cromo VI.

Estimation of chromium (VI) in various body parts of local chicken

International Nuclear Information System (INIS)

Mahmud, T.; Rehman, R.; Anwar, J.; Abbas, A.; Farooq, M.

2011-01-01

Chicken is a common type of meat source in our food. It is fed with the feed containing small pieces of leather having Cr (VI) which persisted in it during chrome tanning process. The core purpose of present study was to determine the concentration of Cr (VI) in different body parts of chicken like leg, arm, head, heart, liver and bone. Estimation of Cr (VI) was done by preparing the sample solutions after ashing and digestion with nitric acid, by atomic absorption spectrophotometer. The results depicted that the meat part of leg had higher mean concentration (1.266 mg/kg) with 0.037 mg/kg standard error while the lowest average concentration was found in arm (0.233 mg/kg) with standard error as 0.019 mg/kg. In case of bones, the maximum mean concentration was found in head (1.433 mg/kg) with standard error as 0.670 mg/kg. The concentration of Cr (VI) was not found similar in meat and bones of chicken by employing Kruskal Wallis Test. (author)

Implementation of MP_Lite for the VI Architecture

Energy Technology Data Exchange (ETDEWEB)

Chen, Weiyi [Iowa State Univ., Ames, IA (United States)

2001-01-01

MP_Lite is a light weight message-passing library designed to deliver the maximum performance to applications in a portable and user friendly manner. The Virtual Interface (VI) architecture is a user-level communication protocol that bypasses the operating system to provide much better performance than traditional network architectures. By combining the high efficiency of MP_Lite and high performance of the VI architecture, they are able to implement a high performance message-passing library that has much lower latency and better throughput. The design and implementation of MP_Lite for M-VIA, which is a modular implementation of the VI architecture on Linux, is discussed in this thesis. By using the eager protocol for sending short messages, MP_Lite M-VIA has much lower latency on both Fast Ethernet and Gigabit Ethernet. The handshake protocol and RDMA mechanism provides double the throughput that MPICH can deliver for long messages. MP_Lite M-VIA also has the ability to channel-bonding multiple network interface cards to increase the potential bandwidth between nodes. Using multiple Fast Ethernet cards can double or even triple the maximum throughput without increasing the cost of a PC cluster greatly.

Modification of zirconium diphosphate with salicylic acid and its effect on the uranium (Vi) sorption

International Nuclear Information System (INIS)

Almazan T, M. G.; Garcia G, N.; Simoni, E.

2014-10-01

The surface of zirconium diphosphate (ZrP 2 O 7 ) was modified with salicylic acid and its effect was evaluated on the uranium (Vi) sorption. The modified surface of the material was analyzed with different analytical techniques among which are included the atomic force microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy. This analysis allowed showing that the salicylic acid is being held on the surface of the zirconium diphosphate. The reactivity of modified zirconium diphosphate compared with uranium (Vi) was investigated using the classical method of batch sorption. The analysis of sorption isotherms shows that the salicylic acid has an important effect in the uranium (Vi) sorption. According to the study conducted, the interaction among the uranium (Vi) and the surface of zirconium diphosphate modified with the salicylic acid most likely leads to the complexes formation of binary (U(Vi)/ZrP 2 O 7 ) and ternary (U(Vi)/salicylate/ZrP 2 O 7 ) surface. (Author)

A (Si VI) (1.92 micrometer) coronal line survey of galactic nuclei

Science.gov (United States)

Marconi, A.; Moorwood, A. F. M.; Salvati, M.; Oliva, E.

1994-11-01

We present the results of a (Si VI) lambda 1.962 emission line survey of active, starburst and IRAS luminous galaxies. The line was only detected in known Seyfert type 1 and 2 nuclei confirming previous suggestions that (Si VI) is related to Seyfert activity. By modeling the formation of (Si VI) and (Fe VIII) lambda 6087 we find further strong evidence that these lines arise in gas photoionized by the active nucleus although collisional ionization e.g. by shock fronts may be important in some galaxies exhibiting (Fe VII) much greater than (Si VI). Our failure to detect (Si VI) in the IRAS ultraluminous galaxies does not exclude the possible presence of obscured Active Galactic Nuclei (AGNs), particularly as some of the known Seyferts were also not detected. Molecular hydrogen lines (a by-product of our spectra) are common in all galaxy types including several IRAS ultraluminous galaxies whose H2 equivalent widths (Wlambda less that 20 A) are 'normal'and much lower than the extreme value (Wlambda approximately = 70 A) found in NGC 6240 and NGC 1275. 'Bare' Seyferts have Wlambda(H2) less than 1 A and a factor greater than or approximately 10 lower than starbursts, and we do not confirm previous claims of H2 line emission in the quasar 3C273. Although the ratio of H2 to (Si VI) emission varies over a wide range it does not appear to provide a useful indicator of activity type or to impose constraints on the He excitation mechanism.

Chromium sorption and Cr(VI) reduction to Cr(III) by grape stalks and yohimbe bark.

Science.gov (United States)

Fiol, Núria; Escudero, Carlos; Villaescusa, Isabel

2008-07-01

In this work, two low cost sorbents, grape stalks and yohimbe bark wastes were used to remove Cr(VI) and Cr(III) from aqueous solutions. Batch experiments were designed to obtain Cr(VI) and Cr(III) sorption data. The mechanism of Cr(III) and Cr(VI) removal and Cr(VI) reduction to Cr(III) by the two vegetable wastes, has been investigated. Fourier transform infrared rays (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis on solid phase were performed to determine the main functional groups that might be involved in metal uptake and to confirm the presence of Cr(III) on the sorbent, respectively. Results put into evidence that both sorbents are able to reduce Cr(VI) to its trivalent form.

Extraction and Separation of Uranium (VI) and Thorium (IV) Using Tri-n-dodecylamine Impregnated Resins

International Nuclear Information System (INIS)

Metwally, E.; Saleh, A.Sh.; El-Naggar, H.A.

2005-01-01

Extraction of U(VI) and Th(IV) from chloride and nitrate solutions with tri-n- dodecylamine impregnated on Amberlite XAD4, was investigated. The distribution of U(VI) and Th(IV) was studied at different concentrations of acid, salting-out agent, extractant, aqueous metal ion and other parameters. Absorption spectral studies have been investigated for uranium species in both aqueous HCl solution and the resin phase. From these studies, it is suggested that the tetrachloro complex of U(VI) is formed in the extraction of uranium (VI) from hydrochloric acid solutions by TDA impregnated resin. Stripping of the extracted U(VI) and Th(IV) was assayed with HCl and HNO 3 . Finally, the separation of uranium from thorium and fission products in HCl media was achieved

Speciation of Cr(VI) in environmental samples in the vicinity of the ferrochrome smelter.

Science.gov (United States)

Sedumedi, Hilda N; Mandiwana, Khakhathi L; Ngobeni, Prince; Panichev, Nikolay

2009-12-30

The impact of ferrochrome smelter on the contamination of its environment with toxic hexavalent chromium, Cr(VI), was assessed by analyzing smelter dusts, soil, grass and tree barks. For the separation of Cr(VI) from Cr(III), solid samples were treated with 0.1M Na(2)CO(3) and filtered through hydrophilic PDVF 0.45 microm filter prior to the determination of Cr(VI) by electrothermal atomic absorption spectrometry (ET-AAS). Ferrochrome smelter dust was found to contain significant levels of Cr(VI), viz. 43.5 microg g(-1) (cyclone dust), 2710 microg g(-1) (fine dust), and 7800 microg g(-1) (slimes dust) which exceeded the maximum acceptable risk concentration (20 microg g(-1)). The concentration of Cr(VI) in environmental samples of grass (3.4+/-0.2), soil (7.7+/-0.2), and tree bark (11.8+/-1.2) collected in the vicinity of the chrome smelter were higher as compared with the same kind of samples collected from uncontaminated area. The results of the investigation show that ferrochrome smelter is a source of environmental pollution with contamination factors of Cr(VI) ranging between 10 and 50.

Speciation of Cr(VI) in environmental samples in the vicinity of the ferrochrome smelter

International Nuclear Information System (INIS)

Sedumedi, Hilda N.; Mandiwana, Khakhathi L.; Ngobeni, Prince; Panichev, Nikolay

2009-01-01

The impact of ferrochrome smelter on the contamination of its environment with toxic hexavalent chromium, Cr(VI), was assessed by analyzing smelter dusts, soil, grass and tree barks. For the separation of Cr(VI) from Cr(III), solid samples were treated with 0.1 M Na 2 CO 3 and filtered through hydrophilic PDVF 0.45 μm filter prior to the determination of Cr(VI) by electrothermal atomic absorption spectrometry (ET-AAS). Ferrochrome smelter dust was found to contain significant levels of Cr(VI), viz. 43.5 μg g -1 (cyclone dust), 2710 μg g -1 (fine dust), and 7800 μg g -1 (slimes dust) which exceeded the maximum acceptable risk concentration (20 μg g -1 ). The concentration of Cr(VI) in environmental samples of grass (3.4 ± 0.2), soil (7.7 ± 0.2), and tree bark (11.8 ± 1.2) collected in the vicinity of the chrome smelter were higher as compared with the same kind of samples collected from uncontaminated area. The results of the investigation show that ferrochrome smelter is a source of environmental pollution with contamination factors of Cr(VI) ranging between 10 and 50.

Vi har selv designet naturens love

DEFF Research Database (Denmark)

Bentzen, Martin Mose

2014-01-01

ForskerZonenNaturlovene er universelt gyldige i de flestes øjne. De gælder altid, uanset hvad vi tænker. Men dette billede står ikke uimodsagt i videnskabsfilosofien, og der er meget, der tyder på, at det ikke er specielt empirisk korrekt...