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Sample records for hamzisti ba bakteri

  1. ANALISIS CEMARAN BAKTERI Escherichia coli ANALISIS CEMARAN BAKTERI Escherichia coli ANALISIS CEMARAN BAKTERI Escherichia coli

    OpenAIRE

    ANGGREINI, RAHAYU

    2015-01-01

    2015 RAHAYU ANGGREINI coli Penelitian ini bertujuan untuk melakukan identifikasi cemaran bakteri E. coli O157:H7 pada daging sapi di kota Makassar. Sampel pada penelitian ini sebanyak 72 sampel Kata Kunci : Daging sapi, pasar tradisional, E. coli, E. coli O157:H7, kontaminasi bakteri, identifikasi E. coli O157:H7.

  2. POPULASI BAKTERI HETEROTROF DI PERAIRAN PULAU BULANG BATAM

    Directory of Open Access Journals (Sweden)

    Notowinarto Notowinarto

    2015-11-01

    Full Text Available Sepanjang pesisir pantai pada perairan di kawasan Kecamatan Bulang Kota Batam sebagai lokasi penelitian dengan banyak dijumpai pemukiman penduduk dan industri galangan kapal (Shipyard serta banyak mengeluarkan limbah yang langsung dibuang keperairan terbuka. Sampai saat ini masih minim informasi tentang populasi bakteri heterotrof, sehingga di perlukan pengkajian secara biologi perairan yakni bagaimana populasi bakteri Heterotrof di perairan Pulau Bulang Batam. Tujuan mengetahui estimasi total bakteri umum dan virus (TBU;TBV serta hubungan antara padatan populasi bakteri dengan kondisi in-situ kualitas antar perairan yang berbeda. Penelitian bersifat lapangan insitu dengan pengambilan sampling secara teknik purposive sampling dan ek-situ yakni sampel air segera di bawa ke Laboratorium Uji Kesehatan Ikan dan Lingkungan Balai Budidaya Laut. Analisis dengan pendekatan deskriptif dan kuantitatif untuk mencari hubungan antara perkiraan populasi bakteri heterotrof dengan kondisi kualitas air antar lokasi sampling menggunakan pendekatan analisis sidik ragam (Ansira. Hasil sebagai berikut: a bahwa diperkiraan populasi bakteri heterotroph baik total bakteri umum (TBU maupun total bakteri virus (TBV yang nyata dengan kecenderungan (trend meningkat akibat adanya perubahan kualitas in-situ perairan, yakni pada lokasi Kuala Bulang 2 dan Selat Awa; b Kandungan nitrat memperlihatkan kisaran nilai yang tinggi berada di lokasi Selat Awa dan terendah terdapat pada stasiun Teluk Sepaku serta ammonium memperlihatkan nilai tertinggi pada stasiun Kuala Bulang Dua dan kandungan phospat kandungan tertinggi di stasiun Selat Awa, sehingga akan menimbulkan terjadinya peledakan populasi (blooming; dan c Hubungan korelasi antar stasiun pengamatan terhadap sebaran kepadatan total bakteri umum maupun vibrio (TBU/TBV tampaknya tidak nyata (non-signifikan. Walaupun tingkat hubungan (nilai r lebih dari 50%. Begitupula terhadap parameter kualitas air, hanya ada indikasi korelasi

  3. Isolasi, Karakterisasi dan Potensi Bakteri Aerob sebagai Pendegradasi Limbah Organik

    OpenAIRE

    Zahidah, Dinda; Shovitri, Maya

    2013-01-01

    Penelitian ini dilakukan untuk mengisolasi dan mengkarakterisasi bakteri aerob yang mampu mendegradasi amilum, protein dan selulosa. Penelitian ini berhasil memurnikan dan mengkarakterisasi isolat bakteri C5 yang cenderung masuk ke genus Bacillus. Berdasarkan uji kualitatif amilolitik, selulolitik dan proteolitik, diketahui bahwa isolat C5 memiliki indeks amilolitik (IA) sebesar 0.93, indeks selulolitik (IS) sebesar 1.95 dan indeks proteolitik (IP) sebesar 1.39

  4. strong>Alle bakterier deler gener ved horisontal overførselstrong>

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik

    2007-01-01

    Bakterier har ikke blot en langt større mangfoldighed i deres stofskifte end dyr og planter. Ny forskning viser, at de også i stor stil udveksler gener, der koder for dele af deres stofskifte med andre bakterier. Det giver bakterier mulighed for at tilpasse sig nye levevilkår, men betyder også...

  5. Resistensi dan Sensitivitas Bakteri terhadap Antibiotik di RSU dr. Soedarso Pontianak Tahun 2011-2013

    OpenAIRE

    Nurmala Nurmala; IGN Virgiandhy; Andriani Andriani; Delima F. Liana

    2015-01-01

    Salah satu upaya untuk mengurangi resistensi, pemberian antibiotik harus berdasarkan pola bakteri penyebab infeksi dan kepekaan bakteri terhadap antibiotik. Tujuan penelitian ini untukmengetahui pola bakteri, resistensi dan sensitivitasnya terhadap antibiotik di RSU dr. SoedarsoPontianak tahun 2011-2013. Penelitian deskriptif dengan pendekatan retrospektif dilakukan RSU dr. Soedarso, Pontianak. Sampel penelitian adalah hasil pemeriksaan kultur dan uji kepekaan spesimen pus pasien yang diperi...

  6. ISOLASI DAN KARAKTERISASI BAKTERI DENITRIFIKASI SEBAGAI AGEN BIOREMEDIASI NITROGEN ANORGANIK

    Directory of Open Access Journals (Sweden)

    Khairul Syahputra

    2011-08-01

    Full Text Available Denitrifikasi merupakan salah satu proses utama yang mengurangi kandungan senyawa nitrogen anorganik di lingkungan. Proses ini dapat digunakan untuk mengatasi kelebihan senyawa nitrogen anorganik yang tinggi di kolam budidaya perikanan. Penelitian ini bertujuan untuk mengisolasi dan mengkarakterisasi isolat bakteri denitrifikasi sebagai agen bioremediasi senyawa nitrogen anorganik. Sebanyak 21 isolat bakteri pereduksi nitrat berhasil diisolasi dari medium pengkayaan dengan konsentrasi nitrat 100 µM dan 1500 µM. Sebanyak 6 isolat merupakan kelompok bakteri denitrifikasi (fermentatif negatif dan 15 isolat termasuk kelompok bakteri fermentatif. Berdasarkan hasil seleksi didapatkan isolat HNF5 dan LNF mempunyai kemampuan reduksi nitrat yang tinggi. Aktivitas reduksi nitrat terjadi dari awal inkubasi, di mana aktivitas paling cepat terjadi pada fase eksponensial pertumbuhan bakteri. Isolat HNF5 dan LNF memiliki kecepatan maksimum reduksi nitrat (Vmaks 0,17 mM.h-1 dan 0,16 mM.h-1 dengan nilai konstanta Michaelis-Menten (Km 0,40 mM dan 0,28 mM. Identifikasi dengan sekuen 16S-rRNA memperlihatkan bahwa isolat HNF5 dan LNF mempunyai kemiripan dengan Pseudomonas aeruginosa.

  7. DETEKSI GEN-GEN PENYANDI FAKTOR VIRULENSI PADA BAKTERI VIBRIO

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    Ince Ayu Khairani Kadriah

    2011-04-01

    menggunakan isolat bakteri yang diisolasi dari budidaya udang windu di berbagai daerah di Sulawesi Selatan dan Jawa. Pada penelitian ini digunakan primer spesifik untuk mendeteksi gen-gen virulen toxR gene, hemolysin (vvh gene, dan GyrB gene dengan metode PCR. Dari 35 isolat yang diisolasi, 20 isolat terdeteksi memiliki gen virulensi dan 8 di antaranya memiliki dua gen virulen. Spesies bakteri yang memiliki gen virulen adalah: V.harveyi, V. parahaemolyticus, V. mimicus, dan V. campbelli

  8. Penerapan Metode Dempster Shafer Untuk Mendiagnosa Penyakit Dari Akibat Bakteri Salmonella

    Directory of Open Access Journals (Sweden)

    Mikha Dayan Sinaga

    2016-12-01

    Full Text Available Infeksi dari bakteri Samonella dapat menyerang saluran gastrointestin yang mencakup perut, usus halus, dan usus besar atau kolon. Beberapa spesies salmonella dapat menyebabkan infeksi melalui makanan. Termasuk ke dalamnya adalah Salmonella Typhi yang mengakibatkan penyakit tifus, dan Salmonella Shigella yang mengakibatkan penyakit disentri dan diare. Masih banyak orang yang belum mengetahui gejala-gejala dari infeksi bakteri ini serta bagaimana cara untuk mendiagnosa dengan nilai kepastian yang tinggi. Untuk dapat mengetahui tingkat kepastian infeksi bakteri ini peneliti menggunakan metode Dempster-Shafer. Metode ini dipilih karena metode ini dianggap mampu untuk memberikan tingkat kepastian yang tinggi. Metode Dempster-Shafer adalah representasi, kombinasi dan propogasi ketidakpastian, dimana teori ini memiliki beberapa karakteristik yang secara instutif sesuai dengan cara berfikir seorang pakar, namun dasar matematika yang kuat. Hasil dari penelitian ini adalah untuk membuat aplikasi sistem pakar yang dapat mendiagnosa bakteri dari akibat bakteri salmonella dengan menggunakan metode Dempster Shafer. Kata Kunci  : Sistem Pakar,Metode Dempster Shafer, Bakteri Salmonella.

  9. Efek Antibakteri Ekstrak Daun Mimba (Azadirachta indica A. Juss) terhadap Bakteri Vibrio algynoliticus Secara In Vitro

    OpenAIRE

    Uli Ayini; Siti Harnina B.; Titis Candra Dewi

    2014-01-01

    Budidaya udang windu di Indonesia telah berkembang pesat. Salah satu kendala budidaya udang adalah penyakit Vibriosis yang disebabkan oleh bakteri Vibrio algynoliticus. Tujuan penelitian ini adalah untuk mengetahui efek antibakeri ekstrak daun mimba terhadap bakteri Vibrio algynoliticus. Penelitian ini menggunakan metode dilusi untuk mengetahui efek antibakteri ekstrak daun mimba terhadap bakteri Vibrio algynoliticus secara in vitro. Konsentrasi ekstrak yang digunakan (%) yaitu: 0; 2,5; 5; 7,...

  10. Perbedaan Cara Penyebaran Suspensi terhadap Jumlah Bakteri pada Media Eosin Methylene Blue Agar

    Directory of Open Access Journals (Sweden)

    Ahmad Nuzuludin Kadri

    2015-06-01

    Full Text Available Dalam rangka pengawasan mutu secara biologis dilakukan pengujian laboratorium untuk mengisolasi dan melakukan jumlah penghitungan jumlah bakteri patogen (enumerasi. Tujuan dari penelitian ini adalah untuk mengetahui perbedaan cara penyebaran suspensi dengan menggunakan batang gelas bengkok, mikropipet dan ose terhadap jumlah bakteri yang terhitung pada media Eosin Methylene Blue Agar. Sampel diambil dari air susu kambing yang kemudian dihitung jumlah bakteri-nya dengan tiga kelompok perlakuan yaitu menggunakan batang gelas bengkok, mikropipet dan ose. Data hasil penelitian dianalisis menggunakan sidik ragam, bila hasilnya berbeda nyata maka dilanjutkan dengan uji Duncan. Jumlah bakteri yang terhitung dengan menggunakan batang gelas bengkok, mikropipet dan ose per ml berturut-turut mengandung 9.722.222 cfu, 68.944.444 cfu dan 116.444.444 cfu. Dengan sidik ragam, perlakuan cara penyebaran dengan menggunakan mikropipet dan ose berbeda sangat nyata (P<0,01 terhadap jumlah bakteri yang terhitung dengan menggunakan batang gelas bengkok. Setelah di uji dengan uji Duncan, rata-rata jumlah bakteri yang terhitung dengan menggunakan mikropipet dan ose lebih tinggi sangat nyata (P<0,01 dibandingkan dengan menggunakan batang gelas bengkok, sedangkan rata-rata jumlah bakteri yang terhitung menggunakan ose lebih tinggi sangat nyata (P<0,01 dibandingkan dengan menggunakan mikropipet. Kesimpulan dari penelitian ini adalah terdapat perbedaan cara penyebaran suspensi dengan menggunakan batang gelas bengkok,mikropipet dan ose terhadap jumlah bakteri pada media EMBA. Penyebaran bakteri menggunakan ose lebih banyak (P<0,01 dibandingkan mikropipet dan batang gelas bengkok. Sedangkan penyebaran bakteri menggunakan mikropipet lebih banyak (P<0,01 dibandingkan dengan gelas bengkok.

  11. AKTIVITAS ANTIMIKROBA YOGURT BERBASIS AIR KELAPA MENGHAMBAT BAKTERI PATOGEN SECARA IN VITRO

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    Lindawati S. A.

    2014-11-01

    Full Text Available Yogurt merupakan minuman susu yang difermentasi dengan menggunakan bakteri asam laktat Lactobacillus bulgaricus dan Streptococcus thermophyllus sebagai starter. Tujuan penelitian untuk mengetahui kemampuan tertinggi dari yogurt berbasis air kelapa dalam menghambat pertumbuhan bakteri pathogen (Salmonella, Staphylococcus, Klebsiela pneumonia dan E.coli secara in vitro. Penelitian ini menggunakan rancangan acak lengkap (RAL dengan empat perlakuan dan empat ulangan. Keempat perlakuan tersebut: Ko: susu skim 12%+air; K1: susu skim 12%+air kelapa gading; K2: susu skim 12%+kelapa gading bulan; K3: susu skim 12%+air kelapa hijau. Peubah yang diamati adalah aktivitas antimikroba yogurt terhadap bakteri pathogen (Salmonellatyphi, Staphylococcus, Klebsiella pneumonia dan E.coli, total plate count (TPC, total bakteri asam laktat dan E,coli. Hasil penelitian menunjukkan bahwa aktivitas antimikroba tertinggi diperoleh pada yogurt berbasis air kelapa bulan terhadap bakeri Salmonella typhi dan Staphylococcus masing-masing sebesar 0,21 dan 0,26 cm dengan total bakteri asam laktat1,1×107 cfu/mL sedangkan untuk Klebsiella pneumonia dan E.coli diperoleh pada yogurt berbasis air kelapa gading sebesar 0,38 dan 0,64 mm dengan total bakteri asam laktat 3,1×106 cfu/mL.Dari hasil penelitian dapat disimpulkan bahwa yogurt berbasis air kelapa gading, bulan, hijau dan tanpa air kelapa memiliki aktivitas antimikroba berspektrum luas (menghambat bakteri gram positif dan negatif.

  12. Molekylærbiologer afslører bakteriers giftige hemmelighed

    DEFF Research Database (Denmark)

    Boesen, Thomas; Andersen, Gregers Rom

    2005-01-01

    niveau af, hvordan toksinet ødelægger sit mål. Forskningsresultaterne publiceres i det ansete tidsskrift Nature i dag.   De nye resultater kan få stor betydning, da denne type toksiner produceres af en række alvorlige sygdomsfremkaldende bakterier såsom pertussis (der giver kighoste), difteri, kolera......, coli og pseudomonas. Danskere vaccineres mod pertussis og difteri, og kolera er praktisk taget udryddet grundet forbedret hygiejne, men under naturkatastrofer og i udviklingslandene er disse bakterier stadigvæk skyld i sygdom og død.   Pseudomonas bakterier er i den vestlige verden mest kendt fra...

  13. IDENTIFIKASI BAKTERI DARI IKAN TONGKOL (Euthynnus affinis YANG DIPERDAGANGKAN DI PASAR IKAN KEDONGANAN BALI

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    Gusti Ayu Dianti Violentina

    2016-06-01

    Full Text Available Ikan tongkol (Euthynnus affinis merupakan ikan konsumsi yang disukai masyarakat.Pengetahuan tentang bakteri yang ditemukan pada tubuh ikan ini sangat penting untuk tujuan kesehatan masyarakat dan kajian biologi ikan.  Penelitian ini bertujuan untuk mengidentifikasi bakteri yang berasosiasi dengan ikan tersebut.Bakteri dari usus ikan diambil secara aseptis dan ditumbuhkan pada Blood Agar dan Nutrient Broth. DNA total dari kultur agar cair diisolasi dengan chelax, gen 16S RNA diamplifikasi dengan PCR menggunakan primer universal dengan produk sekitar 1300 bp. Produk PCR dirunut dengan metode Big-Dye termination. Hasilnya disepadankan dan dianalisis dengan MEGA 6.0. Pada penelitian ini, 14 spesies bakteri yang memiliki > 99% kesamaan dengan data GenBankteridentifikasi, yaitu Photobacterium leiognathi, Uruburuella testudinis, Aeromonas molluscorum, Psychrobacter celer, Psychrobacer faecalis, Acinetobacter johnsonii, Vibrio gallicus, Bacillus megaterium, Vagococcus fessus, Shewanella baltica, Shewanella algae, Rothia nasimurium, Myroides phaeus dan Yersinia ruckeri. Peran bakteribakteri tersebut dalam biologi ikan dan kesehatan masyarakat perlu dikaji lebih lanjut.

  14. SELEKSI BAKTERI METHANOTROF (PEREDUKSI EMISI GAS METAN DI LAHAN SAWAH BERDASARKAN AKTIVITAS ENZIM METHAN MONOOKSIGENASE

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    Maimuna Nonci

    2016-03-01

    Full Text Available Kehadiran bakteri metanotrof pada daerah rhizosfer padi sangat dibutuhkan untuk mereduksi metan yang dihasilkan oleh bakteri metanogen, sehingga tidak terjadi emisi gas metan ke atmosfer. Penelitian ini bertujuan untuk melakukan koleksi dan seleksi bakteri methanotrof asal rhizosfer tanaman padi yang mampu menghasilkan enzim metan monooksigenase. Pengambilan sampel dilakukan secara acak pada tiga fase pertumbuhan tanaman padi yaitu fase vegetatif, reproduktif dan pematangan. Koleksi isolat dilakukan dengan metode isolasi dan pemurnian. Seleksi isolat dilakukan dengan pengujian reaksi gram, motil, indol, aerob/anaerob dan aktivitas enzim monooksigenase dianalisis dengan metode kolorimetrik.  Hasil penelitian diperoleh 52 koleksi isolat bakteri. Berdasarkan reaksi gram terseleksi 22 isolat gram negatif, berdasarkan analisis kolorimetrik  diperoleh 10 isolat  menghasilkan enzim metan monooksigenase.

  15. PERBANDINGAN EFEKTIVITAS EKSTRAK DAUN SAGA DAN DAUN SIRIH TERHADAP BAKTERI STAPHYLOCOCCUS AUREUS SKRIPSI Diajukan Untuk Melengkapi Salah Satu Syarat Mencapai Gelar Sarjana Kedokteran Gigi

    OpenAIRE

    USEMAHU, RIFDATUL AHWAL

    2015-01-01

    2015 Latar Belakang: Bakteri adalah salah satu mikroorganisme yang menyebabkan penyakit, salah satunya adalah bakteri Staphylococcus aureus. Daun sirih dan daun saga memiliki sifat antibakteri karena mempunyai zat aktif yang berguna untuk meghambat pertumbuhan bakteri. Tujuan: Penelitian ini bertujuan untuk melihat perbedaan efektivitas antara daun saga dan daun sirih. Metodologi : Jenis penelitian ini adalah eksperimental laboratories. Sampel penelitian ini adalah ...

  16. IDENTIFIKASI DAN UJI POTENSI BAKTERI LIPOLITIK DARI LIMBAH SBE (SPENT BLEACHING EARTH SEBAGAI AGEN BIOREMEDIASI

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    Fitralia Elyza

    2016-03-01

    Full Text Available Limbah minyak kelapa sawit yang terbanyak adalah SBE (Spent Bleaching Earth, limbah ini mengandung residu minyak tinggi yang dapat mencemari lingkungan, 30% residu minyak pada limbah SBE dapat digunakan bakteri untuk pertumbuhannya, sehingga adanya bakteri mampu menjadi agen bioremediasi pencemaran SBE. Penelitian dilakukan untuk mendapatkan bakteri lipolitik sebagai agen potensial bioremediasi pada limbah SBE. Metode pengambilan sampel limbah SBE secara random sampling. Sampel tanah diambil secara acak dari beberapa titik area limbah SBE. Bakteri diisolasi dari sampel limbah SBE, kemudian dilakukan tahapan yaitu : pemurnian, seleksi, uji potensi, bakteri berpotensi mereduksi lipid dikarakterisasi dan diidentifikasi genusnya. Hasil penelitian menunjukkan bahwa Aktivitas enzim lipase yang tinggi menandakan bahwa bakteri lipolitik bekerja optimal merombak zat pencemar. Bakteri yang memiliki potensi sebagai agen bioremediasi terdiri dari genus Citrobacter (B1, Enterobacter (B2 dan Acinetobacter (B3. The most palm oil waste is SBE (Spent Bleaching Earth, this waste had many reduced lipid that got pollution for inviroments, Bacteria can use lipid from SBE as much as 30% for growed. So that consist of bacteria in SBE as a potensial agent for remediation. This study aims to obtain lipolytic bacteria as a potential agent of bioremediation. The method of sampling soil were taken at random from SBE waste, Bacteria were isolated from the SBE waste, then they were selected into steps : performed purification, selection, potential test, then characterized and identified it’s genus of potential bacteria. The results showed that the higest activity enzyme of lipolytic indicated that the lipolytic bacteria worked optimal for reduce polution. Bacteria had potential as a bioremediation agent consisting of genus Citrobacter (B1, Enterobacter (B2 and Acinetobacter (B3.

  17. Kajian patogenisitas bakteri Edwardsiella ictaluri pada ikan patin Pangasionodon hypophthalmus

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    Wiwik Susanti

    2016-12-01

    Full Text Available ABSTRACT One of major problem of striped catfish Pangasionodon hypophthalmus culture is enteric septicemia of catfish (ESC, bacterial disease of Edwardsiella ictaluri, caused of more than 50% of mortalities. This reaserch was aimed to determine pathogenicity of local isolate E. ictaluri. Thirty individu of five group fishes, 6–10 g in body weight, injected intraperitoneally with 0,1 mL of bacteria suspension of 102 cfu/mL; 104 cfu/mL; 106 cfu/mL; 108 cfu/mL; 1010 cfu/mL; and PBS as control, were culture in 18 of 60×40×45 cm3 aquarium for seven days. External organs of fish (skin and abdomen and internal organs (liver, kidney, and brain were examined macroscopicly and microscopicly. Internal organ sample were taken on the 5th day for histopatologic test while blood sample was on the 1st, 3rd, and 5th day after infection. Mortality rate was count to reach LD50. Clinical signs and pathology anatomy of co-infection fish showed vertical swim, petechial hemorrhage in the skin, dropsy, ascites in the abdominal cavity, pale liver and the kidney was dark red. Histopathology showed hydropic degeneration, fatty degeneration, hemorrhage and necrosis in the liver, melano macrophage center (MMC and necrosis in the kidneys, hemorrhage, and inflammatory cell infiltrates were also found in the kidneys and brain. Decreased of hematocrit and hemoglobin values of all tread group were statistically significant different (P<0,05 compared to controls. LD50 dose was 2,8×104 cfu/mL. The result indicated that E. ictaluri was very pathogenic on striped catfish P. hypophthalmus.  Keywords: Edwardsiella ictaluri, enteric septicemia of catfish (ESC, pathogenicity, striped catfish  ABSTRAK Salah satu kendala yang dijumpai pada budidaya ikan patin Pangasionodon hypophthalmus yaitu serangan penyakit bakterial. Enteric septicemia of catfish (ESC adalah penyakit infeksi bakteri Edwardsiella ictaluri yang dapat menyebabkan kematian ikan patin sampai >50%. Penelitian ini

  18. ISOLASI BAKTERI ENDOFIT DARI DAUN SIRIH (Piper betle L. SEBAGAI ANTIBAKTERI TERHADAP Escherichia coli DAN Staphylococcus aureus

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    desi - sagita

    2017-03-01

    Full Text Available Bakteri endofit adalah salah satu alternatif penghasil senyawa antimikroba. Keberadaan bakteri dalam tanaman memungkinkan bakteri menghasilkan senyawa bioaktif yang sama seperti yang terkandung dalam tanaman inangnya. Penelitian ini bertujuan untuk mengisolasi dan mengidentifikasi bakteri endofit yang memiliki kemampuan menghambat pertumbuhan bakteri lainnya. Aktifitas antibakteri diukur menggunakan metode Kirbi Bauer. Sirih (Piper bettle adalah tanaman yang telah digunakan oleh banyak orang karena mengandung senyawa yang baik untuk kesehatan. Jumlah bakteri endofit yang berhasil diisolasi adalah 13 isolat yaitu E1, E2, E3,E4,E7,E8, E9, E10, E11, E12 dan E13. Berdasarkan uji aktifitas antibakteri, 6 dari 13 isolat endofit yang berpotensi memberikan aktifitas antibakteri. 5 dari isolat tersebut yang mampu menghambat pertumbuhan bakteri Staphyl,ococcus aureus dan E8 yang aktifitas nya tinggi dengan diameter zona bening 18.96 mm dan hanya 1 isolat yaitu E7 yang mampu menghambat  Escherichia coli dengan diameter zona bening 14.01 mm.

  19. DNA sekventering af bakterier i renseanlæg

    DEFF Research Database (Denmark)

    Albertsen, Mads; Nierychlo, Marta; Nielsen, Per Halkjær

    nye muligheder, som vi ikke har turde drømme om indtil nu. Siden 2006 har vi i samarbejde med 54 danske renseanlæg, rådgivere (Krüger, Kemira) og Dansk Spildevandsteknisk Forening indsamlet prøver til MiDAS (Den Mikrobielle Database for Aktivt Slam) for at undersøge mikrobiologien og dens relation til...... drift og design af anlæggene. Vi kan nu f.eks. se hvilke bakteriearter, som findes i de danske anlæg, hvilke der er hyppige, hvilke anlægsparametre der er vigtige for artssammensætningen, og hvor lang tid det tager at få en stabil proces efter ændringer af drift eller procesdesign. Desuden giver de MiDAS...... karakterisering af mikrobiologien bliver brugt til, og hvordan den nye viden, der er indsamlet i MiDAS over de sidste 10 år, begynder at udmønte sig i konkrete værktøjer til trouble-shooting på de enkelte renseanlæg. Disse vil bl.a. omfatte forbedret identifikation og kontrol af visse trådformede bakterier samt...

  20. KERENTANAN IKAN NILA SULTANA, RED NIFI, SRIKANDI DAN AUREUS TERHADAP INFEKSI BAKTERI Streptococcus agalactiae

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    Rita Febrianti

    2015-06-01

    Full Text Available Penelitian ini bertujuan untuk menguji kerentanan empat strain ikan nila, yaitu: Sultana, Red NIFI, Srikandi, dan Aureus terhadap infeksi bakteri Streptococcus agalactiae. Ikan uji berukuran 15-20 g/ekor dan berasal dari populasi, serta batch umur yang sama. Infeksi bakteri S. agalactiae dilakukan secara buatan melalui penyuntikan intra peritoneal (IP pada dosis 104 cfu/mL, sedangkan kelompok kontrol diinjeksi dengan larutan Phosphate Buffered Saline (PBS. Pengamatan dilakukan terhadap gejala klinis dan mortalitas ikan uji yang berlangsung selama 14 hari. Hasil penelitian menunjukkan bahwa seluruh strain ikan nila mengalami respons yang sama terhadap infeksi bakteri S. agalactie yang ditandai dengan munculnya gejala klinis seperti: warna gelap/menghitam, sirip geripis, nekrosa pada mulut, mata menonjol, opaque, ulcer, dan dropsy. Kerentanan tertinggi terhadap infeksi bakteri S. agalactiae yang dimanifestasikan dengan rataan persentase mortalitas ikan uji diperoleh pada ikan nila Aureus sebesar 72%, Sultana 50%, Srikandi 36%, Red NIFI sebesar 24%, dan kontrol tidak ada mortalitas. Setelah diuji tantang, kadar limfosit mengalami kenaikan, netrofil dan monosit mengalami penurunan.

  1. KARAKTERISASI ENZIM KITOSANASE DAR] ISOLAT BAKTERI KPU 2123 DAN APLIKASINYA UNTUK PRODUKS1 OLIGOMER KITOSAN

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    Yusro Nuri Fawzya

    2009-06-01

    Full Text Available Penelitian ini merupakan sebagian dari rangkaian penelitian mengenai eksplorasi enzim kitinolitik dari mikroba lingkungan laut, khususnya dari limbah udang. Tujuan penelitian ini adalah untuk mengidentifikasi isolat bakteri KPU 2123 dari limbah udang, mengkarakterisasi dan mengaplikasikan enzim kitosanase yang dihasilkan oleh bakteri tersebut untuk produksi oligomer kitosan dan menguji bioaktivitas oligomer kitosan tersebut sebagai antitumor dan antibakteri. Karakterisasi enzim dilakukan dengan menguji aktivitas enzim pada berbagai suhu dan pH. Selain itu juga ditentukan besarnya aktivitas yang tersisa setelah enzim diinkubasi pada suhu dan lama waktu tertentu. Pengaruh ion logam terhadap aktivitas enzim juga dilihat dengan mereaksikan enzim dengan 1 mM ion logam dalam bentuk larutan khlorida. Hasil penelitian menunjukkan bahwa berdasarkan analisis gen 16S-rRNA, isolat bakteri KPU 2123 memiliki kemiripan 95% dengan Stanotrophomonas maltophilia. Enzim kitosanase dari isolat ini bekerja optimal pada suhu 50 ºC dan pH 6. Enzim ini cukup stabil pada suhu 37 ºC selama 120 menit. Penambahan ion logam berpengaruh terhadap aktivitas enzim. Ion logam Zn²+ (sebagai garam klorida 1 mM menghambat 100% aktivitas enzim tersebut. Penggunaan enzim kitosanase dalam menghidrolisis substrat kitosan, menghasilkan oligomer kitosan yang mengandung tetramer, pentamer dan heksamer Oligor kitosan tersebut mampu menghambat pertumbuhan bakteri Staphylococcus aureus sebesar 10,06% dan dapat menyebabkan kematian sel HeLa dengan LC50 pada dosis 120 ppm.

  2. Efek Antibakteri Ekstrak Daun Mimba (Azadirachta indica A. Juss terhadap Bakteri Vibrio algynoliticus Secara In Vitro

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    Uli Ayini

    2014-03-01

    Full Text Available Budidaya udang windu di Indonesia telah berkembang pesat. Salah satu kendala budidaya udang adalah penyakit Vibriosis yang disebabkan oleh bakteri Vibrio algynoliticus. Tujuan penelitian ini adalah untuk mengetahui efek antibakeri ekstrak daun mimba terhadap bakteri Vibrio algynoliticus. Penelitian ini menggunakan metode dilusi untuk mengetahui efek antibakteri ekstrak daun mimba terhadap bakteri Vibrio algynoliticus secara in vitro. Konsentrasi ekstrak yang digunakan (% yaitu: 0; 2,5; 5; 7,5; 10; 12,5 dan sebagai kontrol terdiri dari kontrol positif, dan kontrol negatif. Pengumpulan data untuk menentukan MIC (Minimum Inhibitory Concentration dilakukan dengan membandingkan kejernihan kultur di medium TSB 2% pada berbagai konsentrasi yang berbeda, dengan kontrol positif dan kontrol negatif. Penentuan MBC (Minimum Bacterisidal Concentration dilakukan dengan melihat ada tidaknya dan jumlah koloni bakteri Vibrio alginolyticus yang muncul pada medium subkultur TSA 2% setelah inkubasi 24 jam. Hasil penelitian menunjukkan nilai MIC yaitu konsentrasi 5%, hal ini ditunjukkan dengan tabung yang mulai jernih. Nilai MBC ekstrak daun mimba terhadap bakteri Vibrio alginolyticus adalah konsentrasi 12,5% ditandai dengan sudah tidak munculnya  koloni bakteri Vibrio alginolyticus. Berdasarkan penelitian ini dapat disimpulkan bahwa ekstrak daun mimba dapat memberikan efek antibakteri terhadap bakteri Vibrio alginolyticus secara in vitro.Tiger shrimp cultivation in Indonesia has been growing rapidly. The main obstacle is the shrimp farming vibriosis disease caused by the bacterium Vibrio algynoliticus. The aim of this research was to determine the effects of neem leaf extract antibakeri against Vibrio algynoliticus. This study used a dilution method to determine the antibacterial effect of neem leaf extract against Vibrio algynoliticus bacteria in vitro. The concentration of the extract used (%: 0; 2.5; 5; 7.5; 10; 12.5 and as a control consisting of a positive

  3. Aplikasi Isolat Bakteri Indigenous Ubi Kayu Karet (Manihot glaziovii pada Fermentasi Pembuatan Mocaf

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    K Kamsina

    2017-12-01

    Full Text Available Indigenous bacteria isolate of cassava rubber (Manihot glaziovii is an isolate of native bacteria which is available in rubber cassava tubers. Rubber cassava tuber is a cassava with a high content of cyanide acid (HCN. The study was aimed to see the ability of indigenous bacteria isolate of cassava cultivar rubber (BUG1 on mocaf making fermentation. This study used a completely randomized design with treatments (A addition of starter indigenous bacteria isolates of rubber variety (BUG1, (B without isolates, and (C without  fermentation. The resulting mocaf product was conducted a chemical tests consisted of moisture, ash, starch, acid degree, coarse fiber, and HCN content, while organoleptic tests consisted of color, aroma, and texture. The analysis results on the various treatments showed that the optimal treatment of mocaf flour produced was the addition of indigenous bacteria isolate starter of rubber variety (BUG1.ABSTRAKIsolat bakteri indigenous ubi kayu karet (Manihot glaziovii merupakan isolat bakteri asli yang berada dalam umbi ubi kayu karet. Ubi kayu kultivar  karet merupakan ubi kayu dengan kandungan asam sianida (HCN tinggi. Penelitian bertujuan untuk mempelajari kemampuan isolat bakteri indigenous ubi kayu kultivar karet (BUG1 pada fermentasi pembuatan mocaf. Penelitian ini menggunakan rancangan acak lengkap (RAL dengan perlakuan (A pemberian starter isolat bakteri indigenous varietas karet (BUG1, (B tanpa isolat, dan (C tanpa fermentasi. Terhadap produk mocaf  yang dihasilkan dilakukan uji kimia meliputi kadar air,  abu, pati, derajat asam, serat kasar, dan kadar HCN, sedangkan uji organoleptik meliputi warna, aroma, dan tekstur. Hasil analisis terhadap berbagai perlakuan menunjukkan perlakuan optimal untuk tepung mocaf  yang dihasilkan adalah pemberian starter isolat bakteri indigenous varietas karet (BUG1.

  4. IDENTIFIKASI METABOLIT SEKUNDER DAN AKTIVITAS ANTIBAKTERI EKSTRAK DAUN SUNGKAI (Peronema canescens JACK. TERHADAP BEBERAPA BAKTERI PATOGEN

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    Arsyik Ibrahim

    2012-12-01

    Full Text Available A research which identification of secondary metabolites and antibacterial activity test from methanol exstract of leaf Sungkai (Peronema canencens Jack to several pathogens bacterial, which aims to identification of secondary methabolites and determine the antibacterial activity from crude methanol extract of leaf Sungkai (P. canencens Jack. against Streptococcus mutans, Salmonella thyposa, Bacillus subtilis and Staphylococcus aureus bacteria. Material test obtained by maceration with methanol, then tested for activity. Minimum Inhibition Concentration (MIC value extract was determined by liquid dilution and the followed by scratches on solid media method.  Minimum Kill Concentration (KBM value extracts was determined by agar diffusion method with using paper disks.The results secondary metabolite identify form extracts of leaves P. canencens obtainable derived alkaloid, terpenoids - steroids, flavonoids, and tannin compounds. Methanol extract have the antibacterial activity. Minimum Inhibition Concentration (MIC value of extract is concentration of 20% for bacteria S. mutans, S.thiposa and S.aureus, while for the B. subtilis is konsentration of 15%. Minimum Kill Concentration (KBM values exstract at a concentration of 5% effective at killing S. mutans and S. thyposa bacteria, while the concentration of 1% effective to bacteria B.subtilis and S.aureus. Key words: P. canencens Jack,  antibacteria activity, S. mutans, S. thiposa, B. subtillis, S. aureus   ABSTRAK   Telah dilakukan penelitian identifikasi metabolit sekunder dan aktivitas antibakteri ekstrak metanol daun Sungkai (P.canencens Jack terhadap beberapa bakteri patogen. Penelitian ini bertujuan untuk mengidentifikasi metabolit sekunder dan mengetahui aktifitas antibakteri dan Kadar Hambat Minimum (KHM dan Nilai Kadar Bunuh Minimum (KBM ekstrak kasar metanol daun Sungkai (P.canencens Jack. terhadap bakteri  Streptococcus mutans, Salmonella thyposa, Bacillus subtilis dan

  5. Transformasi α-Pinena dengan Bakteri Pseudomonas aeruginosa ATCC 25923

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    Nanik Wijayati

    2014-03-01

    Full Text Available Indonesia adalah Negara utama yang memproduksi minyak atsiri di dunia. Minyak terpentin adalah minyak atsiri yang dihasilkan dari destilasi getah pinus Pinus merkusi J ungh. Et. De. Vr. Tujuan penelitian ini adalah untuk meningkatkan nilai minyak terpentin dengan mengubah kandungan utamanya, α-pinena menjadi senyawa baru menggunakan P. Aeruginosa dalam metode mikrobiologi. Minyak terpentin diambil dari Perhutani Laboratorium Jawa Tengah, dibuat dengan seri konsentrasi 0,5%, 1%, 2%, dan 4%. Minyak terpentin diinokulasi dalam suspensi P. areuginosa selama 48 jam pada suhu kamar (25-28oC. Hasilnya diekstraksi menggunakan dietil eter. Filtrat Terpentin dianalisis menggunakan GCdan IR. Hasil analisis GC menunjukkan puncak baru di konsentrasi 0,5%, 1%, dan 2%, tetapi dalam konsentrasi 4% tidak menunjukkan puncak baru. Hasil IR menunjukkan hidroksil (OH- dan C-O alkohol. Berdasarkan penelitian ini, dapat disimpulkan bahwa minyak terpentin dapat ditransformasi untuk menjadi senyawa yang mengandung gugus-OH melalui metode mikrobiologi dengan menggunakan bakteri P. aeruginosa. Indonesia is the main producer of essential oil in the world. Turpentine oil is an essential oil which is obtained from pine resin distillation of Pinus merkusi Jungh. et. De.Vr. The aim of this experiment was to increase the value of turpentine oil by changing its main content, i.e. α-pinene, into a new compound using P. aeruginosa in microbiological method. Turpentine oil was collected from Perhutani Central Java Laboratory, and was made into 0.5%; 1%; 2%; and 4% concentrations and it was inoculated in P. areuginosa suspension for 48 hours in room temperature (25°C-280C. The result was extracted using diethylether. The filtrate of turpentine was analyzed using GC and IR. The GC analysis result showed a new peak in 0.5%; 1%; and 2% concentrations, but in the 4% concentration didn’t show a new peak. The IR result showed alcohol with hydroxyl (-OH and –C–O groups. This

  6. Resistensi dan Sensitivitas Bakteri terhadap Antibiotik di RSU dr. Soedarso Pontianak Tahun 2011-2013

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    Nurmala Nurmala

    2015-09-01

    Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 Salah satu upaya untuk mengurangi resistensi, pemberian antibiotik harus berdasarkan pola bakteri penyebab infeksi dan kepekaan bakteri terhadap antibiotik. Tujuan penelitian ini untukmengetahui pola bakteri, resistensi dan sensitivitasnya terhadap antibiotik di RSU dr. SoedarsoPontianak tahun 2011-2013. Penelitian deskriptif dengan pendekatan retrospektif dilakukan RSU dr. Soedarso, Pontianak. Sampel penelitian adalah hasil pemeriksaan kultur dan uji kepekaan spesimen pus pasien yang diperiksa di Bagian Mikrobiologi Unit Labolatorium Kesehatan (ULK. Dari 111 sampel,terdapat 21 jenis bakteri. Bakteri gram-negatif lebih banyak dari gram-positif, yaitu 70,7% dan 29,3%.Tiga bakteri terbanyak adalah Citrobacter freundii (18%, P. aeruginosa (17,1% dan Staphylococcusepidermidis (15,3%. Resistensi tertinggi bakteri adalah terhadap metronidazol (96,4%, sefaleksin(95,8%, sefuroksim (92,2%, oksasilin (91,7% dan sefadroksil (91,5% dan sensitivitas tertinggibakteri terhadap piperasilin/tozobaktam (89,7%, meropenem (82,9%, imepenem (78,1%, amikasin(76,3%, fosfomisin/trometamol (59,5% dan levofloksasin (56,1%. Kata kunci: bakteri, antibiotik, resistensi, sensitivitas, pus. Resistance and Sensitivity of Bacteria to Antibioticsat dr. Soedarso Hospital Pontianak 2011-2013 Abstract An effort to reduce resistance, antibiotics prescription should be based on information about pattern of bacteria and  sensitivity to antibiotics. The aim of the study is to  determine the patternof bacteria, resistance and sensitivity to antibiotics at dr. Soedarso Hospital Pontianak 2011-2013. This research is a descriptive study with retrospective approach. Samples were culture and sensitivity test result in pus specimen of dr. Soedarso Hospital patient’s examined at ULK. Thenumber of samples in this study were 111 samples. There were 21 type of bacterias. Gram-negativebacterias were found more than gram

  7. PEMERIKSAAN BAKTERI LEPTOSPIRA PADA SAMPEL DARAH MANUSIA SUSPECT LEPTOSPIROSIS MENGGUNAKAN METODE PCR (POLYMERASE CHAIN REACTION

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    Sefrita Tri Utami

    2014-01-01

    Full Text Available ABSTRACTLeptospirosis is a zoonotic disease, which is caused by leptospira. Leptospirosis cases often show no specificclinical symptoms and is difficult to diagnose without testing samples in the laboratory. Testing using PCR(Polymerase Chain Reaction is considered more accurate than the other methods. Components required in theexamination Leptospira bacteria in human blood samples using PCR method is DNA template, DNA polymeraseenzyme, forward primer (PU1 and SU1 and reverse primer (Lep R1, nuclease free water, Mg 2 +, and dNTPs.Examination of Leptospira bacteria in human blood samples include sampling, DNA isolation, examination byPCR, and electrophoresis running.Key words: leptospirosis, Leptospira, PCR methodsABSTRAKLeptospirosis adalah penyakit zoonosis yang disebabkan oleh bakteri Leptospira. Kasus leptospirosis seringtidak menunjukkan gejala klinis yang spesifik dan sulit didiagnosis tanpa pengujian sampel di laboratorium.Pengujian dengan menggunakan metode PCR (Polymerase Chain Reaction dinilai lebih akurat dibandingkandengan metode yang lain. Komponen-komponen yang dibutuhkan dalam pemeriksaan bakteri Leptospira padasampel darah manusia menggunakan metode PCR adalah DNA template, enzim polymerase, Primer PU 1 danPrimer SU 1, Primer Lep R1, air, Mg2+ , dan dNTP. Pemeriksaan bakteri Leptospira pada sampel darah manusiameliputi pengambilan sampel, isolasi DNA, pemeriksaan dengan metode PCR, dan running elektroforesis.Kata kunci: leptospirosis, Leptospira, metode PCR

  8. UJI EFEKTIVITAS ANTIBAKTERI EKSTRAK ETANOL DAUN SAMBILOTO (Andrographis paniculata Nees TERHADAP BAKTERI Staphylococus aureus

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    Yuska Novi Yanti

    2017-03-01

    Full Text Available Tumbuhan memiliki zat kimia aktif yang memiliki potensi besar salah satunya adalah membunuh atau menghambat pertumbuhan bakteri. Salah satu tanaman yang digunakan sebagai obat tradisional adalah tanaman sambiloto (Andrographis paniculata Nees yang mempunyai berbagai macam manfaat bagi kesehatan manusia,berbagai aktivitas farmakologi dari sambiloto adalah antiinflamasi,antibakteri,antipiretik dan antioksidan.Sampel dalam penelitan ini adalah koloni Staphylococcus aureus dan ekstrak kental tanaman sambiloto (Andrographis paniculata Nees . Ekstraksi dengan metode maserasi Salanjutnya di rotary dengan menggunakan Rotary evaporator dan dilakukan uji susut pengeringan. Kemudian ekstrak dibagi menjadi lima perlakuan yaitu 10 µg/ml, 50 µg/ml, 100 µg/ml, 500 µg/ml, 1000 µg/ml dibuat kontrol posistif dan negatif lalu dilakukan pembuatan media NA dan NB. Selanjutnya dibuat peremajaan bakteri dan pembuatan larutan uji lalu dilalukan pengujian daya hambat dengan metode cakram lalu diikubasi dan diukur diameter zona hambat.Dari hasil pengujian menunjukan bahwa semua konsentrasi ekstrak sambiloto memiliki daya hambat terhadap pertumbuhan bakteri Staphylococcus aureus. Daya hambat ekstrak sambiloto ditunjukkan dengan adanya zona bening disekitar cakram. Diketahui bahwa pada dosis 100 µg/mL, 1000 µg/mL memiliki daya hambat lemah dan dilanjutkan dengan analisa SPSS diperoleh hasil yang tidak berbeda secara signifikan.

  9. PERAN PEMERINTAH DALAM PENANGGULANGAN PENCEMARAN AIR TANAH OLEH BAKTERI E. COLI DI KOTA YOGYAKARTA

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    Fajar Winarni

    2014-03-01

    Full Text Available This study is an empirical legal research that uses primary and secondary data. The result of this  study is to be used f or the handling of  E.  coli  contamination where it  is the government ’s role to procure chlorine diffusers and monitor the quality of drinking water. The high level of contamination caused by the E. coli bacteria is due to the poor sanitation system and the close proximity of wells to septic tanks. Meanwhile, other constraints faced by the government include the lackof routine monitoring, lack of sanitation workers, and lack of proper implementation of the standardtechnical guidance on Procedures Planning Septic Tank with Absorption Systems. Penelitian ini merupakan penelitian hukum empiris yang menggunakan data primer dan sekunder. Hasil penelitian ini adalah dalam rangka penanggulangan pencemaran bakteri E. coli dimana Pemerintahberperan dalam pengadaan alat chlorine diffuser, sosialisasi hidup bersih, pengawasan kualitas air minum, dan sebagainya. Tingginya pencemaran bakteri E. coli dikarenakan sistem sanitasi yang buruk, dan jarakyang dekat antara sumur dengan saluran septic tank. Sementara itu kendala yang dihadapi antara lainPemerintah tidak melakukan pengawasan secara rutin, terbatasnya petugas sanitasi, tidak dilaksanakannyapetunjuk teknis SNI tentang Tata Cara Perencanaan Tangki Septik dengan Sistem Resapan.Kata Kunci: peran pemerintah, pencemaran, bakteri E. coli.

  10. Pemanfaatan Serbuk Gergaji Menjadi Biobutanol dengan Hidrolisis Selulase dan Fermentasi Bakteri Clostridium Acetobutylicum

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    Hayuni Devina Fajariah

    2014-09-01

    Full Text Available Biobutanol adalah jenis alkohol ikatan C-4 (C4H9OH yang terbuat dari biomassa. Penelitian ini dilakukan dengan memanfaatkan limbah kayu yang dihasilkan dari proses penggergajian kayu yang mengandung selulosa (55%, hemiselulosa (14%, dan lignin (21%. Biobutanol diproduksi dengan cara hidrolisis enzim selulase dan fermentasi bakteri Clostridium acetobutylicum. Variabel pada penelitian ini adalah penambahan enzim selulase pada proses hidrolisis (penambahan enzim atau tanpa penambahan enzim, pH awal proses fermentasi (5 atau 7 dan jumlah penambahan starter bakteri Clostridium acetobutylicum (5 atau 10 ml dengan variasi lama proses fermentasi 2,4,6,8,10,12 hari. Parameter dalam penelitian ini adalah analisa kadar selulosa, gula tereduksi, dan kadar butanol. Berdasarkan hasil penetian, diketahui bahwa proses hidrolisis dengan penambahan enzim selulase, kondisi awal fermentasi pH 5 dan penambahan inokulum bakteri Clostridium acetobutylicum sebanyak 10 ml dengan lama waktu fermentasi 12 hari merupakan kondisi yang paling efektif menghasilkan kadar butanol tertinggi dari 50 gram limbah serbuk gergaji. Kadar butanol tertinggi sebesar 1,88 % dari 1 µL sampel hasil fermentasi yang diinjeksikan ke dalam kromatografi gas.

  11. KARAKTERISASI SIFAT-SIFAT BIOKIMIA EKSTRAK KASAR LIPASE EKSTRASELULER BAKTERI Azospirillum sp.PRD1

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    Santi Nur Handayani

    2011-11-01

    Full Text Available Enzim lipase mempunyai peranan penting dalam katalis berbagai reaksi industri satu diantaranya pembuatan flavor melalui reaksi esterifikasi. Lipase adalah biokatalis yang berperan besar dalam aplikasi bioteknologi, seperti dalam sintesis biopolimer, biodiesel, produksi obat, dan produksi flavor. Peningkatan penggunaan lipase untuk industri mendorong dilakukan penelitian untuk mendapatkan sumber-sumber lipase baru. Sumber lipase yang potensial salah satunya adalah bakteri Azospirillum sp.PRD1 dari isolat lokal Laboratorium Mikrobiologi, Fakultas Biologi Universitas Jenderal Soedirman. Tujuan penelitian adalah untuk mendapatkan ekstrak kasar lipase dan menentukan karakteristik sifat-sifat biokimiawinya. Metode yang digunakan antara lain peremajaan bakteri Azospirillum sp.PRD1, dan produksi inokulum, penentuan waktu produksi optimum dan fase pertumbuhan bakteri, ekstraksi dan produksi ekstrak kasar lipase dan penentuan karakteristik sifat-sifat biokimiawinya. Hasil penelitian diperoleh ekstrak kasar lipase dari inokulum berumur 7 jam dan medium produksi dengan induser minyak zaitun yang diinkubasi selama 3 jam memiliki aktivitas spesifik 7,0547 Unit/mg. Lipase ekstrak kasar optimum pada pH 7, suhu 40 oC dan waktu inkubasi selama 25 menit. Lipase merupakan metaloenzim dengan kofaktor Zn2+ , Mn2+, Hg2+, Ca2+, Co2+ and Mg2+.

  12. Efektifitas Jahe Merah (Zingiber officinale Var. Rubrum sebagai Additif Pakan dan Antimikrobia terhadap Pertumbuhan Bakteri Anaerob dan Coliform Secara In Vivo pada Ayam Pedaging

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    J.R. Manullang

    2015-10-01

    Full Text Available Jahe merah (Zingiber officinale Var. Rubrum dikenal sebagai bakteriasida. Penelitian ini bertujuan untuk mengetahui aktivitas antibakterial bubuk jahe terhadap pertumbuhan bakteri anaerob dan coliform (Escherichia coli dan Salmonella sp. secara in vivo pada Broiler. Penelitian ini menggunakan dua puluh empat DOC dengan berat badan 40,7 g. Pemberian bubuk jahe diberikan pada Broiler selama 5 hari dengan konsentrasi ekstrak jahe merah yaitu, 0,5, 1, dan 1,5% per kg pakan. Peubah yang diamati adalah berat badan, asupan pakan dan koloni bakteri. Hasil penelitian menunjukkan terdapat pengaruh ekstrak jahe merah pada total koloni bakteri yang cenderung menurun dengan semakin tinggi konsentrasi ekstrak jahe merah, semakin tinggi efek hambatan pertumbuhan bakteri. Dapat disimpulkan bahwa ekstrak jahe merah memiliki sejumlah aktivitas antibakteri untuk pertumbuhan bakteri anaerob dan coliform (E. coli dan Salmonella sp..

  13. FORMULASI PRODUK SUSU FERMENTASI KERING DENGAN PENAMBAHAN BAKTERI PROBIOTIK Lactobacillus casei DAN Bifidobacterium longum

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    Dida Hani Rahman

    2012-11-01

    Full Text Available ABSTRACTFermented milk is a healthy product that has many benefits especially for human digestive tract. Manufacturing of probiotic fermented milk products as a functional food with a viable long shelf life needs to be developed. The purpose of this study was to formulate a dried fermented milk product using probiotic bacterias. The experimental design study was a complete random design with 4 treatments using different lactic acid bacteria (LAB: A1 (Streptococcus lactis: 0.5%; A2 (Streptococcus lactis: 0.25% and Lactobacillus casei: 0.25%; A3 (Streptococcus lactis: 0.25%, Lactobacillus bulgaricus: 0.125%, Streptococcus thermophiles: 0.125%; and A4 (Streptococcus lactis: 0.25% and Bifidobacterium longum: 0.25%. The highest level of hardness was A2 product and the highest level of tenderness is A1 product. Results of proximate analysis showed that dried fermented milk products had high levels of the protein, calcium, and phosphorus. Microbiological test results showed that the amount of lactic acid bacteria (BAL in dried fermented milk products were eligible based on CODEX: 243 (2003. Statictical analysis using ANOVA in the hedonic quality test showed that the treatments were significantly different (p 0.05 on the attributes of color, aroma, hardness, and flavor except texture.Key words: dried fermented milk, functional food, probiotic, lactic acid bacteria (LABABSTRAKSusu fermentasi merupakan produk kesehatan yang mempunyai banyak manfaat terutama untuk saluran pencernaan manusia. Pembuatan produk susu fermentasi probiotik sebagai makanan fungsional yang mempunyai kelangsungan hidup dan daya simpan yang lama perlu dikembangan. Tujuan penelitian ini adalah untuk memformulasikan susu fermentasi kering menggunakan bakteri probiotik. Desain penelitian yang digunakan adalah rancangan acak lengkap dengan 4 perlakuan menggunakan 4 bakteri asam laktat (BAL, (Streptococcus lactis, 0.5%, A2 (Streptococcus lactis; 0.25% dan Lactobacillus casei; 0.25%, A3

  14. ISOLASI DAN KARAKTERISASI BAKTERI TANAH SAWAH DI DESA SUKAWALI DAN DESA BELIMBING, KABUPATEN TANGERANG

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    Arief Pambudi

    2017-08-01

    Full Text Available Abstrak Penggunaan pupuk kimia secara berlebih dapat menyebabkan kerusakan tanah dan menyebabkan ekosistem yang ada didalamnya terganggu. Plant growth-promoting rhizobacteria (PGPR adalah bakteri yang hidup di daerah rizosfer tanaman yang dapat berperan sebagai biofertilizer, biostimulan dan bioprotektan. Penelitian ini bertujuan untuk memperoleh dan mengetahui karakteristik bakteri tanah yang berasal dari dua area persawahan, lokasi pertama di Desa Sukawali (TGR 1 dan lokasi kedua di Desa Belimbing (TGR 2, Kabupaten Tangerang. Penelitian dilakukan dengan mengambil sampel tanah, kemudian sampel dikultur dalam media agar nutrien dengan pengenceran bertingkat. Total bakteri dihitung dan isolat yang diperoleh diuji kemampuan dan karakternya dalam menambat nitrogen (BPN, melarutkan fosfat (BPF, menghasilkan indole acetic acid (IAA, menghasilkan Hidrogen Cyanide (HCN, aktivitas katalase, jenis Gram dan karakter motilitas. Total bakteri yang dapat tumbuh dari kedua lokasi sebanyak 2,4x106 CFU/g dan 1,8x106 CFU/g. Kedua lokasi diperoleh total 45 isolat dengan seluruhnya positif BPN, 42 isolat positif BPF, 24 isolat menghasilkan IAA, 27 isolat menghasilkan HCN, 43 isolat katalase positif, 39 isolat Gram positif, 6 isolat Gram negatif, serta 41 isolat motil. Berdasarkan uji yang dilakukan, terdapat 16 isolat yang berpotensi sebagai pupuk hayati.  Abstract Excessive use of chemical fertilizer may cause soil damage and disturb the ecosystem. Plant growth-promoting rhizobacteria (PGPR is a consortium bacteria that live in plant rhizosphere which acts as biofertilizer, biostimulant, and bioprotectant. The objective of this research is to isolate and investigate the characteristics of soil bacteria originating from two rice fields in Sukawali Village (TGR 1 and Belimbing Village (TGR 2, Tangerang Regency. The research was conducted by collecting soil samples and then culturing the bacteria onto nutrient agar medium with serial dilution. The total bacteria

  15. Penapisan Bakteri yang Diisolasi dari Tambak Udang sebagai Kandidat Probiotik pada Budi daya Udang Windu, Penaeus monodon

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    Muliani Muliani

    2016-11-01

    Full Text Available Penelitian ini bertujuan mendapatkan bakteri probiotik untuk budi daya udang windu P. monodon. Penelitian meliputi beberapa tahapan yaitu (1 isolasi bakteri dari tambak udang; (2 uji daya hambat terhadap Vibrio  harveyi; (3 karakterisasi secara fisiologi dan biokimia; (4 pertumbuhan bakteri pada beberapa konsentrasi NaCl; (5 pertumbuhan bakteri pada beberapa tingkat salinitas; (6 uji patogenisitas bakteri terhadap pascalarva udang windu; (7 uji tantang dengan V. harveyi dalam wadah pemeliharaan pascalarva udang windu; dan (8 analisis gen 16S-rRNA bakteri yang diisolasi dari tambak. Sedikitnya 14 isolat dari 2.228 isolat bakteri yang diisolasi dari tambak, potensial dijadikan probiotik pada budi daya udang windu. Sintasan udang windu tertinggi pada perlakuan yang menggunakan isolat BN2067. Isolat BT950 dan BT95 paling potensial menghambat pertumbuhan V. harveyi baik secara In vitro maupun In vivo. Hasil analisis gen 16Sr-RNA menunjukkan bahwa BT950 dan BT951 termasuk dalam kelompok Brevibacillus sp., sedangkan BN2067 termasuk dalam kelompok Vibrio vulnificus CMCP6 chr. This experiment was aimed for finding-out probiotic bacteria on tiger shrimp P. monodon culture. The research included several steps i.e. 1 isolation of bacteria from tiger shrimp pond; 2 inhibition test of  bacteria against V. harveyi; 3 biochemical and physiological characterization; 4 growth of bacteria at different concentration of NaCl; (5 growth of bacteria at different salinities; (6 pathogenicity test of bacteria to tiger shrimp post larvae, (7 challenge test of bacteria against V. harveyi in tiger shrimp culture media; (8 16S-rRNA gene analysis of  bacteria isolated from shrimp pond. Fourteen isolates of 2,228 isolates of bacteria isolated from tiger shrimp pond were potential for probiotic bacteria on tiger shrimp culture. The highest survival rate of tiger shrimp was obtained from those treated with BN2067 isolate. The potential isolates to inhibit V. harveyi both In

  16. SELEKSI BAKTERI PROBIOTIK UNTUK BIOKONTROL VIBRIOSIS PADA LARVA UDANG WINDU, Penaeus monodon MENGGUNAKAN CARA KULTUR BERSAMA

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    Widanarni Widanarni

    2009-04-01

    Full Text Available Penelitian ini bertujuan untuk memperoleh bakteri probiotik yang mampu menghambat pertumbuhan Vibrio harveyi mengggunakan metode kultur bersama. Sebanyak 51 isolat kandidat probiotik berhasil diisolasi dari larva udang dan lingkungan pemeliharaannya di Balai Pengembangan Benih Ikan Air Payau dan Udang (BPBILAPU, Pangandaran serta hatcheri udang PT Biru Laut Khatulistiwa dan tambak udang intensif di Lampung. Dari total isolat tersebut setelah diseleksi secara in vitro menggunakan metode kultur bersama dipilih 3 isolat kandidat probiotik yang paling potensial dalam menekan atau menghambat pertumbuhan V. harveyi MR 5399 RfR yakni 1Ub, P20Bf, dan 10a. Ketiga isolat tersebut selanjutnya digunakan pada uji patogenisitas dan uji tantang pada larva udang windu. Hasil uji patogenisitas dengan konsentrasi bakteri 106 CFU/mL menunjukkan bahwa ketiga isolat tersebut tidak bersifat patogen pada larva udang windu. Hasil uji tantang pada larva udang juga menunjukkan bahwa ketiga isolat tersebut mampu meningkatkan sintasan larva udang windu. Nilai sintasan larva pada perlakuan yang selain diinfeksi dengan V. harveyi MR5399 RfR juga ditambah probiotik 1Ub, P20Bf, dan 10a masing-masing adalah 90,0%; 86,7%; dan 78,3% sedangkan pada perlakuan yang hanya diinfeksi dengan V. harveyi MR5399 RfR tanpa probiotik nilai sintasannya hanya mencapai 73,3%. Populasi bakteri V. harveyi pada perlakuan dengan penambahan bakteri probiotik lebih rendah dibanding perlakuan tanpa probiotik, hal ini menunjukkan kemungkinan adanya kompetisi antara bakteri V. harveyi dengan 1Ub. This research was aimed to obtain probiotic bacteria that can be used to inhibit the growth of Vibrio harveyi using co-culture method. This method succeeded in isolating 51 probiotic bacteria candidates from shrimp larva and their rearing environment in Balai Pengembangan Benih Ikan Laut Payau dan Udang (BPBILAPU, Pangandaran and shrimp hatchery of PT Biru Laut Khatulistiwa and intensively managed shrimp pond

  17. PENAPISAN ISOLAT BAKTERI Streptococcus spp. SEBAGAI KANDIDAT ANTIGEN DALAM PEMBUATAN VAKSIN, SERTA EFIKASINYA UNTUK PENCEGAHAN PENYAKIT STREPTOCOCCOSIS PADA IKAN NILA, Oreochromis niloticus

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    Taukhid Taukhid

    2011-04-01

    Full Text Available Riset dengan tujuan untuk memperoleh isolat kandidat yang imunogenik bagi pembuatan vaksin untuk pengendalian penyakit streptococcosis pada ikan nila telah dilakukan. Karakterisasi dilakukan secara biokimia dan API 20 STREP terhadap 15 isolat bakteri Streptococcus spp. Uji Koch’s Postulate kemudian dilakukan untuk mengetahui peran bakteri pada infeksi streptococcosis pada ikan nila. Konfirmasi taksonomis hingga level spesies isolat bakteri S. agalactiae dilakukan dengan teknik Polymerase Chain Reaction (PCR dengan menggunakan primer spesifik. Uji patogenisitas dilakukan terhadap 6 isolat yang terdiri atas 5 isolat S. agalactiae (N3M, N4M, N14G, N17O, NK1 dan 1 isolat S. iniae (N2O. Hasil penapisan menunjukkan bahwa bakteri S. agalactiae (N4M memiliki nilai LD50 terkecil, dan nilai terbesar dimiliki oleh bakteri S. iniae (N2O. Isolat bakteri N4M digunakan sebagai sumber antigen dalam pembuatan vaksin anti streptococcosis. Vaksin disiapkan dalam bentuk sel utuh dan diinaktivasi dengan formalin, pemanasan, dan sonikasi. Nilai titer antibodi dan sintasan tertinggi diperoleh pada kelompok ikan yang divaksin dengan formalin killed vaccine dibandingkan dengan teknik inaktivasi lainnya (heat killed vaccine dan sonicated vaccine.

  18. Efek Larvasida Bakteri Kitinolitik dari Limbah Kulit Udang terhadap Larva Aedes aegypti

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    Dyah Widiastuti

    2016-06-01

    Full Text Available Abstract. Aedes aegypti is a major vector for Dengue, a deadly disease causing death of millions of people in developing countries both in urban and rural populations. Ae. aegypti control using chemical insecticide was always carried out and lead to a widespread insecticide resistance. Therefore, mosquito biological control is needed to replace the usage of chemical insecticide. A chitinolytic bacteria, was isolated from shrimp’s waste (head and shell. The isolate showed chitinolytic activity as a transparent zone in colony inside the synthetic media, containing (w/v- 0,3 % colloidal chitin, 1% pepton, 0,5% yeast extract, 0,1% NaCl, 0,1% K2HPO4, 0,05% MgSO4.7H2O, 0,001% FeSO4.7H2O, 0,001% ZnSO4.7H2O, and each of 0,0001% CuSO4.5H2O, MnSO4.nH2O and CaCl2.2H2O at pH 7 and 300C after 72 h of incubation. The isolate was identified as gram positive group based on gram staining. In the experimental method, four concentrations of chitinolytic bacteria (4%, 8%, 16% and 32% was exposed to Ae. aegypti larvae. The result showed that chitinolytic bacterium degrades exoskeleton of third instar larvae of Ae. aegypti. Degradation of exoskeleton started on the 2nd days and occurred in thorax region. Probit analysis showed LC50 value was obtaninedat concentration of 2%. Keywords: chitinolytic bacteria, shrimp’s waste, Aedes aegypti Abstrak. Aedes aegypti merupakan vektor utama Dengue, penyakit yang menyebabkan kematian jutaan orang di negara-negara berkembang baik pada populasi perkotaan dan pedesaan. Pengendalian Ae. aegypti menggunakan insektisida kimia selalu dilakukan dan menyebabkan resistensi insektisida secara luas. Oleh karena itu, pengendalian nyamuk secara biologis diperlukan untuk menggantikan penggunaan insektisida kimia. Bakteri kitinolitik telah diisolasi dari limbah udang (kepala dan cangkang. Isolat menunjukkan aktivitas kitinolitik berupa zona bening di sekitar  koloni dalam media sintetik yang mengandung (w/v - 0,3% koloidal kitin, 1

  19. Uji Efektivitas Jeruk Nipis (Citrus aurantifolia dalam Mempercepat Laju Disinfeksi Bakteri Escheria Coli pada Proses Solar Water Disinfection

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    Saprian Saprian

    2015-08-01

    Full Text Available Solar Water Disinfection (SODIS memerlukan waktu rata-rata berkisar antara 5-6 jam untuk dapat membunuh bakteri 3-4 Log pada air berkapasitas maksimal 2 liter atau 1 jam dengan suhu di atas 50°C. Penelitian terbaru menunjukkan bahwa dengan mengkombinasikan SODIS dengan psoralens, zat aktif seperti yang terdapat pada jeruk Lemon (Citrus Limon dapat menginaktivasi bakteri hingga 5,6 Log reduksi dalam rentang waktu 30 menit pada suhu 29°C. Mengingat faktor ketersediaan dan harga jeruk lemon di Indonesia maka pada penelitian ini dilakukan pengamatan dengan menggunakan jeruk nipis (Citrus aurantifolia. Penelitian ini dilakukan untuk mengetahui seberapa besar potensi jeruk nipis untuk dipergunakan dalam mempercepat laju disinfeksi pada proses SODIS. Adapun faktor-faktor yang akan dipelajari terkait dengan hubungan antara variasi dosis jeruk nipis, perubahan pH dan suhu air terhadap efisiensi inaktivasi bakteri yang mampu dihasilkan. Variasi jeruk nipis yang digunakan adalah 0%, 2%, 4% dan 6% dengan variasi waktu 0 menit, 30 menit, 60 menit dan 120 menit. Hasil penelitian menunjukkan bahwa perlakuan SODIS dengan menggunakan jeruk nipis mampu menginaktivasi E. coli sebesar 5.4 Log dengan waktu 1 jam pada suhu 32°C. Hal ini menunjukkan bahwa Jeruk nipis berpotensi untuk digunakan dalam mempercepat laju disinfeksi E. coli pada air minum. Kata Kunci : SODIS, E.coli, Psoralens, Jeruk Nipis

  20. POTENSI ANTIMIKROBA EKSTRAK SAMBILOTO (ANDROGRAPHIS PANICULATA NESS. DAN KUNYIT (CURCUMA LONGA LINN. SERTA KOMBINASINYA TERHADAP BAKTERI ESCHERICHIA COLI IN VITRO

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    Luh Putu Happy Sandha

    2015-01-01

    Full Text Available Penggunaan tanaman tradisional sebagai obat telah banyak dikembangkan sebagai solusi pada kasus resistensi antibiotik. Penelitian ini bertujuan untuk menentukan aktivitas antimikroba dari ekstrak sambiloto, kunyit serta kombinasinya terhadap pertumbuhan bakteri gram negatif Esherichia coli. Penelitian ini adalah penelitian eksperimental murni yang dilakukan secara in-vitro. Ekstrak sampel kunyit dan sambiloto diperoleh dari proses ekstraksi menggunakan methanol 95%. Aktivitas antimikroba dinilai dari diameter zona hambat yang terbentuk pada bakteri E. coli dengan metode difusi cakram. Hasil penelitian ini ditemukan bahwa kombinasi ekstrak sambiloto dan kunyit memiliki potensi antimikroba yang bermakna terhadap bakteri E. coli dengan zona hambat sebesar 27,33 mm (p=0,002 pada konsentrasi 15 µg/ml. Ekstrak kunyit tunggal memiliki potensi antimikroba terhadap E. coli pada konsentrasi 15 µg/ml dengan zona hambat 28,67 mm (p=0,004. Ekstrak sambiloto tunggal tidak memiliki potensi antimikroba untuk E. coli. Simpulan penelitian ini yaitu penggunaan kunyit sebagai antimikroba tunggal memiliki potensi yang lebih baik dibandingkan kombinasi ekstrak, sehingga tidak perlu dikombinasi dengan sambiloto.    

  1. UJI AKTIVITAS ANTIBAKTERI EKSTRAK RUMPUT LAUT Kappaphycus alvarezii DAN Eucheuma denticullatum TERHADAP BAKTERI Aeromonas hydrophila DAN Vibrio harveyii

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    Dwi Budi Wiyanto

    2010-04-01

    Full Text Available Penelitian tentang Uji Aktivitas Antibakteri Ekstrak Rumput Laut Kappaphycus alvarezii dan Eucheuma denticullatum Terhadap Bakteri Aeromonas hydrophila dan Vibrio harveyii dilakukan, mengingat banyak dijumpai  penyakit pada usaha budidaya ikan dan udang, terutama bakteri Aeromonas hydrophila dan Vibrio harveyii. Penelitian ini bertujuan untuk mengetahui efektifitas senyawa bioaktif rumput laut K. alvarezii dan E. denticullatum yang diekstrak menggunakan pelarut metanol dan etanol sebagai antibakteri terhadap A. hydrophila dan V. harveyii.  Penelitian dilakukan sebanyak dua tahap, yaitu: (1 Uji aktivitas antibakteri ekstrak rumput laut; dan (2 Analisa senyawa bioaktif yang terdapat pada ekstrak rumput laut, dimana masing-masing tahapan dianalisis menggunakan rancangan acak lengkap faktorial. Hasil penelitian menunjukkan, dua jenis ekstrak rumput laut dengan pelarut metanol dan etanol, mempunyai daya antibakteri terhadap A. hydrophila dan V. harveyii. Ekstrak E. denticullatum dengan pelarut metanol memiliki daya hambat lebih luas dibanding ekstrak K. alvarezii dengan pelarut metanol terhadap A. hydrophila (19.43±0,55 mm. Ekstrak E. denticullatum dengan pelarut metanol memiliki daya hambat lebih luas dibanding ekastrak K. alvarezii dengan pelarut metanol terhadap V. harveyii (19.85±0,23 mm. Asam heksadekanoat merupakan senyawa paling dominan dijumpai pada ekstrak rumput laut K. alvarezii, dan E. denticullatum yang diekstrak menggunakan pelarut metanol. Kata Kunci : Aktivitas Antibakteri, Rumput laut K. alvarezii dan E. denticullatum,  Bakteri A.  hydrophila dan V. harveyii. 

  2. DAYA HAMBAT JUS KULIT APEL MANALAGI (Malus sylvestris Mill. TERHADAP PERTUMBUHAN BAKTERI Staphylococcus aureus DAN Escherichia coli PENYEBAB MASTITIS PADA SAPI PERAH

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    Puguh Surjowardojo

    2016-08-01

    Full Text Available Apel Manalagi (Malus sylvestris Mill. sering dikonsumsi baik secara segar maupun diolah menjadi keripik apel. Pengolahan ini menghasilkan limbah berupa kulit. Kandungan kulit apel Manalagi berupa saponin, flavonoid, tannin, polifenol dan katekin yang dapat berperan sebagai antibakteri, kandungan ini dapat dimanfaatkan sebagai pengganti larutan teat dipping iodip untuk menghambat pertumbuhan bakteri Staphylococcus aureus dan Escherichia coli penyebab mastitis pada sapi perah. Tujuan penelitian ini untuk menentukan apakah jus kulit apel Manalagi dapat menghambat pertumbuhan Staphylococcus aureus dan Escherichia coli penyebab mastitis pada sapi perah serta untuk mengetahui konsentrasi yang lebih baik untuk menghambat pertumbuhan bakteri Staphylococcusaureus dan Escerichia coli. Penelitian ini dilakukan di Laboratorium dengan cara diffusi sumurandengan analisis yang digunakan adalah Rancangan Acak Lengkap (RAL kemudian dilanjutkan dengan menggunakan Uji Beda Nyata Terkecil (BNT. Hasil penelitian menunjukkan bahwa penggunaan juskulit apel Manalagi dengan konsentrasi 10%, 20% dan 30% dapat menghambat pertumbuhan bakteristaphylococcus aureus dan Escherichia coli secara signifikan (P<0,01 dengan hasil terbaik terhadapbakteri Staphylococcus aureus dengan menggunakan konsentrasi 30% sedangkan untuk bakteriEscherichia coli menggunakan konsentrasi 10%. Namun, penggunaan jus kulit apel Manalagi belumdapat mengimbangi iodip dalam menghambat bakteri Escherichia coli. Kesimpulan dari penelitian iniadalah jus kulit apel Manalagi dapat digunakan untuk larutan antiseptik alami untuk teat dipping padasapi perah. Kata kunci: Staphylococcus aureus, Eschericia coli, zona hambat bakteri, mastitis.

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

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    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.

  4. IDENTIFIKASI SENYAWA EKSTRAK ETANOL DAUN MIMBA (Azadirachta indica A.Juss SEBAGAI ANTIBAKTERI SECARA KLT-BIOAUTOGRAFI TERHADAP BAKTERI Stahpylococcus aureus DAN Escherichia coli

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    Nurfijrin Ramadhani

    2017-03-01

    Full Text Available Rendahnya kesadaran masyarakat dan kurangnya sarana kesehatan membuat penyakit infeksi semakin meningkat. Pengobatan secara alami sekarang menjadi pilihan baru sebagai antibakteri, salah satunya adalah mimba. Penelitian sebelumnya menunjukkan bahwa daun mimba dapat menghambat pertumbuhan bakteri, akan tetapi belum diketahui senyawa apa yang berperan sebagai antibakteri tersebut. Penelitian ini bertujuan untuk mengetahui di dalam daun mimba senyawa yang berperan sebagai antibakteri. Penelitian dilakukan dengan metode KLT Bioautografi langsung, dimana hasil maserasi esktrak etanol daun mimba yang telah dielusi ditempelkan ke media yang telah ditanami bakteri Staphylococcus aureus dan Escherichia coli. Zona hambat yang terbentuk dilakukan identifikasi senyawa dengan menggunakan pereaksi semprot Dragendorf, FeCl3, Sitroborat, Lieberman Bouchardat, dan SbCl3. Hasil uji KLT-Bioautografi menunjukkan bahwa daun mimba dapat menghambat pertumbuhan bakteri yang ditandai dengan terbentuknya zona bening masing-masing dengan Rf 0,4 pada bakteri Staphylococcus aureus dan Escherichia coli. Senyawa yang berperan sebagai antibakteri terhadap bakteri Staphylococcus aureus dan Escherichia coli diduga adalah senyawa saponin dimana terbentuk warna ungu dengan pereaksi SbCl3.

  5. POTENSI TUMBUHAN BANGKAL (Nauclea Orientalis UNTUK PENGENDALIAN BAKTERI Aeromonas Hydrophila (POTENTIAL PLANT BANGKAL (Nauclea orientalis FOR CONTROL Aeromonas Hydrophila

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    Siti Aisiah

    2017-02-01

    Full Text Available Tujuan penelitian ini adalah didapatkan metode pengendalian penyakit yang disebabkan oleh bakteri Aeromonas hydrophila pada budi daya ikan yang ramah lingkungan. Dalam penelitian ini dilakukan uji sensitivitas terhadap bakteri A. hydrophila, uji minimal konsentrasi menghambat  bakteri A. hydrophila (uji MIC dan uji toksisitas terhadap ikan nila. Rancangan  yang digunakan untuk  uji toksisitas  adalah rancangan acak lengkap (RAL, dengan 4 perlakuan yaitu A  = Ikan disuntik dengan ekstrak bangkal konsentrasi 20%, B  = Ikan disuntik dengan ekstrak bangkal konsentrasi 40%,  C  = Ikan disuntik dengan ekstrak bangkal konsentrasi 80%, dan D  = Kontrol (ikan tidak disuntik, diulang sebanyak 3 kali. Perlakuan ini didapat dari hasil uji sensitivitas antibakteri bangkal yang mempunyai daya hambat dan daya bunuh paling besar terhadap bakteri A. hydrophila yaitu ekstrak daun bangkal dengan pelarut akuades. Pengujian MIC menunjukkan bahwa ekstrak bangkal-akuades memiliki daya hambat minimal  20 % terhadap aktivitas bakteri A. hydrophila. Hasil uji toksisitas yang dilakukan terhadap ikan nila dengan konsentrasi 20%, 40% dan 80%  mortalitas ikan nila dibawah 50 %. Pengamatan hematologis yaitu eretrosit, leokosit, plasma darah, hematokrit dan leokokrit pada masing-masing perlakuan sebagian besar masih berada dalam kisaran yang normal. Parameter kualitas air yaitu, kadar oksigen terlarut,  pH, amoniak, CO2 dan suhu masih dapat mendukung kehidupan normal ikan nila. The purpose of this study was obtained method of controlling diseases caused by Aeromonas hydrophila in fish farming is environmentally friendly. In this study the sensitivity of the test  A. hydrophila, a minimum test konsentari inhibiting A. hydrophila (MIC test and toxicity test on  tilapia. The design used for toxicity tests is completely randomized design with 4 treatments it A = Fish injected with extracts bangkal concentration of 20 %,  B = Fish injected with extracts bangkal

  6. Identifikasi Carrier Bakteri Streptococcus β hemolyticus Group A pada Murid SD Negeri 13 Padang Berdasarkan Perbedaan Umur dan Jenis Kelamin

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    Fadhila Aini

    2016-01-01

    Full Text Available AbstrakStreptococcus β hemolyticus Grup A atau yang disebut juga Streptococcus pyogenes merupakan salah satu bakteri patogen yang banyak menginfeksi manusia.Bakteri ini dapat ditemukan sebagai carrier di saluran pernafasan terutama pada anak-anak, tidak menimbulkan penyakit tetapi berisiko untuk menyebarkan penyakit. Tujuan penelitian ini adalah menentukan jumlah carrier  bakteri Streptococcus β hemolyticus Grup A pada murid berdasarkan perbedaan umur dan jenis kelamin. Jenis penelitian ini adalah deskriptif cross-sectional dengan menggunakan sampel seluruh murid SD Negeri 13 Padang. Hasil penelitian adalah didapatkan 2 orang murid yang menderita carrier, yaitu pada kelompok usia>8-9 tahun dan >11 tahun. Berdasarkan jenis kelamin yang terdiri dari 54 orang laki-laki dan 50 orang perempuan, didapatkan 2 orang carrier yaitu hanya pada anak laki-laki. Hasil penelitian menunjukkan bahwa carrier bakteri Streptococcus β hemolyticus Group  A terdapat pada anak usia tersebut karena masih kurangnya pengetahuan tentang kebersihan. Carrier yang ditemukan hanya pada anak laki-laki kemungkinan disebabkan mereka lebih sering bermain di luar rumah dan terpapar dengan berbagai bakteri patogen dan kurang memperhatikan kebersihan diri.Kata kunci: carrier, streptococcus β hemolyticus grup A, umur, jenis kelamin AbstractGroup A Streptococcus β hemolyticus or also called Streptococcus pyogenes is one of many pathogenic bacteria that infect humans. These bacteria can be found as a carrier in the respiratory tract especially in children, do not cause disease but can be a risk for spreading the disease. This objective of this study was to determine the amount of the carrier of bacteria group A Streptococcus β hemolyticus based on age and gender differences. This research is a descriptive cross - sectional study using a sample of all students of SD Negeri 13 Padang. Based on the age of 104 students found that students who suffer 2 carrier, which is in the age

  7. Uji Daya Hambat Ekstrak Buah Belimbing Manis (Averrhoa carambola terhadap Pertumbuhan Bakteri Streptococcus pneumoniae secara In Vitro

    Directory of Open Access Journals (Sweden)

    Rita Risandi

    2016-09-01

    Full Text Available AbstrakBuah belimbing manis (Averrhoa carambola merupakan salah satu tanaman Indonesia yang diyakini memiliki khasiat obat. Salah satu manfaat yang dapat diambil dari sari buah belimbing manis (Averrhoa carambola adalah dapat mengobati radang tenggorokan. Radang tenggorokan merupakan salah satu infeksi yang disebabkan oleh bakteri Streptococcus pneumoniae. Tujuan penelitian ini adalah menentukan daya hambat ekstrak buah belimbing manis (Averrhoa carambola terhadap pertumbuhan bakteri Streptococcus pneumoniae  secara in vitro. Metode studi ini ialah eksperimental dengan desain postest only control group design yang dilakukan di Laboratorium Biota Sumatera Universitas Andalas dan Laboratorium Mikrobiologi Fakultas Kedokteran Universitas Andalas dari Agustus sampai Oktober 2014. Hasil penelitian menunjukkan bahwa ekstrak buah belimbing manis (Averrhoa carambola dengan konsentrasi yaitu 5%, 10%, 15% dan 20% tidak memiliki daya hambat terhadap pertumbuhan bakteri Streptococcus pneumoniae.  Hal ini terbukti karena tidak terbentuk zona hambat pada agar darah dan tidak terdapat pengaruh lama kontak ekstrak buah belimbing manis (Averrhoa carambola  terhadap pertumbuhan bakteri Streptococcus pneumoniae secara in vitro. Ekstrak buah belimbing manis tidak memiliki efek antibakteri terhadap pertumbuhan bakteri Streptococcus pneumoniae.Kata kunci: ekstrak buah belimbing manis, Streptococcus pneumoniae, daya hambat Abstract             Star fruit (Averrhoa carambola is a Indonesian plant that is believed to have medicinal properties. One of the benefits that can be drawn from the juice of star fruit (Averrhoa carambola is the ability to treat strep throat. Strep throat is a bacterial infection caused by Streptococcus pneumoniae. The objective of this study was to determine the inhibitory extract of star fruit (Averrhoa carambola on the growth of the bacterium Streptococcus pneumoniae in vitro. This was an experimental  research  with design

  8. Eksplorasi Bakteriosin dari Bakteri Asam Laktat Asal Rusip Bangka dan Kalimantan

    Directory of Open Access Journals (Sweden)

    Arifah Kusmarwati

    2014-06-01

    Full Text Available Penelitian ini dilakukan untuk memproduksi dan mengkarakterisasi bakteriosin yang dihasilkan oleh bakteri asam laktat yang diisolasi dari rusip. Rusip merupakan produk ikan fermentasi tradisional Bangka. Penelitian ini menggunakan sampel rusip yang berasal dari Bangka dan Kalimantan. Sampel diisolasi hingga diperoleh isolat murni yang selanjutnya dilakukan skrining untuk memperoleh isolat yang mampu menghasilkan aktivitas antibakteri tertinggi. Isolat terpilih selanjutnya diidentifikasi dan digunakan untuk memproduksi bakteriosin kasar. Bakteriosin kasar diuji sensitifitasnya terhadap enzim proteolitik dan dikarakterisasi melalui pengujian stabilitas terhadap suhu tinggi, pH, surfaktan, serta stabilitasnya selama penyimpanan. Hasil penelitian menunjukkan bahwa isolat RK4 menghasilkan bakteriosin yang bersifat sensitif terhadap enzim proteolitik seperti proteinase-K dan papain. Bakteriosin tersebut stabil terhadap suhu tinggi dan pH 2–8 serta menghasilkan aktivitas antibakteri yang tertinggi terhadap Staphylococcus aureus. Hasil identifikasi memperlihatkan bahwa isolat RK4 termasuk dalam jenis pediococcus pentosaceus I. Bakteriosin dari Pediococcus pentosaceus I tersebut aktivitasnya distimulasi oleh EDTA, sodium dodecyl sulphate (SDS dan lauryl sarcosine. Namun sebaliknya, bioaktivitasnya tidak dipengaruhi oleh Triton X-100, Tween 20, Tween 80 dan urea. Bakteriosin kasar RK4 stabil pada penyimpanan suhu 37 °C selama 4 minggu dan pada suhu dingin selama 2 minggu.

  9. ANALISIS AKTIVITAS NITROGENASE DAN GEN NIFH ISOLAT BAKTERI RHIZOSFER TANAMAN PADI DARI LAHAN SAWAH PESISIR JAWA BARAT

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    Dwi Ningsih Susilowati

    2016-12-01

    Full Text Available AbstrakPenambatan nitrogen oleh bakteri rhizosfer dapat dimanfaatkan untuk menyiasati dampak salinitas pada tanah sawah pesisir. Kemampuan tersebut disebabkan oleh aktivitas nitrogenase yang disandikan gen nifH pada komponen II. Penelitian  ini bertujuan  menganalisis aktivitas nitrogenase pada kondisi salin dan mengidentifikasi gen nifH. Sebanyak 50 isolat bakteri rhizosfer asal tanah sawah pesisir daerah Eretan dan Patimban, Jawa Barat telah dianalisis. Lima isolat yang menunjukkan aktivitas nitrogenase pada kondisi salin adalah Er B1 3, Er B1 4, Er B1 9, Er B2 10, dan Ptb B1 4. Gen nifH kelima sampel diidentifikasi menggunakan PCR menghasilkan amplikon berukuran ~360 bp. Aktivitas nitrogenase tertinggi berdasarkan Analisis Reduksi Asetilen (ARA diperoleh pada isolat Er B2 10 yang memiliki kekerabatan terdekat dengan bakteri Providencia sp. Hasil yang diperoleh membuktikan bahwa beberapa bakteri asal sawah pesisir dapat menambat nitrogen pada kondisi salin.AbstractThe ability of nitrogen fixation by rhizosphere bacteria could be used to decrease salinity impact in coastal paddy field, due to nitrogenase capability, encoded by a nifH gene in component II. The objectives of this research are to analyze nitrogenase activity in saline condition and identify the presense of the nifH gene. A total of 50 isolates of the rhizosphere bacteria coastal from wetland areas of Eretan and Patimban, West Java, has been isolated and being analyzed. Among them, five isolates i.e. Er B1 3, ER B1 4, Er B1 9, Er B2 10 and Ptb B1 4, showed the nitrogenase activity under saline condition. The polymerase chain reaction (PCR of the nifH gene from those five samples resulted in the amplicon size of  ~360 bp. The highest activity of nitrogenase assessed by acetylene reduction assay (ARA was shown by Er B2 10 which closely related to bacteria of Providencia sp. The obtained result showed that several bacteria from coastal paddy field were able to conduct nitrogen

  10. Pola Resistensi Bakteri pada Sputum Pasien PPOK Terhadap Beberapa Antibiotika di Laboratorium Mikrobiologi RSUP Dr.M.Djamil Periode 2010 − 2012

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    Ashima Sonita

    2014-09-01

    Full Text Available AbstrakPeningkatan resistensi bakteri penyebab PPOK terhadap beberapa antibiotika yang lazim digunakan oleh klinisi dalam pemberian terapi empirik akan menyebabkan berkurangnya keefektifan terhadap terapi PPOK. Hal ini akan berdampak semakin tingginya morbiditas dan mortalitas yang disebabkan oleh PPOK. Penelitian ini bertujuan untuk mengetahui pola resistensi bakteri penyebab PPOK terhadap beberapa antibiotika di Laboratorium Mikrobiologi RSUP.Dr.M.Djamil periode 2010 – 2012. Penelitian ini telah dilaksanakan pada bulan November 2013 sampai dengan Desember 2013 di Laboratotium Mikrobiologi RSUP Dr.M.Djamil Padang. Metode penelitian yang digunakan adalah deskriptif retrospektif. Hasil penelitian mendapatkan bakteri penyebab PPOK adalah Klebsiella spp (42,44%, Streptococcus α hemolyticus (38,37%, Pseudomonas aeruginosa (12,21%, Staphylococcus aureus (4,65%, Proteus mirabilis (1,16%, Staphylococcus epidermidis (0,58% dan Streptococcus pneumoniae (0,58%. Disimpulkan bahwa bakteri tersering pada sputum pasien PPOK adalah Klebsiella spp. Tingkat resistensi tertinggi adalah Ampicillin, sedangkan tingkat kepekaan tertinggi adalah terhadap Netilmycin.Kata kunci: antibiotika, bakteri, resistensiAbstractIncreased resistance of bacteria that cause COPD to some antibiotics that are commonly used by clicicians in the provision of empiric therapy, it will cause a reduction in the effectiveness of the tratment of COPD. This study aimed to determine the resistance pattern of Bacteria in sputum of patients COPD to some antibiotics in Microbiology Laboratory Dr.M.Djamil Hospital Peroid 2010 – 2012. The research method was a descriptive and retrospective. According to the result, the bacteria that causes COPD is Klebsiella spp (42.44%, Streptococcus α hemolyticus (38.37%, Pseudomonas aeruginosa (12.21%, Staphylococcus aureus (4.65%, Proteus mirabilis (1.16%, Staphylococcus epidermidis (0.58%, and Streptococcus pneumoniae (0.58%. It can be concluded that the

  11. Pembuatan Pasta Gigi Katekin Teh Hijau dan Uji Daya Hambat terhadap Bakteri Streptococcus Mutans dan Lactobascillus Ascidopillus

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    Fajriani Fajriani

    2015-06-01

    Peracikan formula dan pembuatan pasta gigi katekin teh hijau dilakukan sesuai hasil uji KHM (MIC. Pasta gigi katekin teh hijau ini dilakukan pengukuran kadar total flavonoid dan total polifenol, selanjutnya pengukuran uji daya hambat pasta gigi katekin teh hijau dilakukan dengan metode difusi menggunakan well (sumuran sebagai reservoar sampel uji terhadap bakteri streptococus mutans dan lactobacilus acidophilus. Hasil diperoleh prodak pasta gigi katekin teh hijau dengan kandungan kadar flavonoid 77% dan kadar polifenol 41%, sedangkan hasil uji diameter hambatan pasta gigi katekin teh hijau terhadap bakteri streptococcus mutans 17,2 mm dan bakteri lactobacillus acidophilus 19,6 mm. Hasil ini menunjukkan bahwa prodak katekin teh hijau ini sangat efektif digunakan sehari-hari sebagai perawatan gigi dan juga sebagai antibakteri kariogenik.   Making Green Tea Catechin Toothpaste and Inhibition Test Against Streptococcus Mutans and Acidophilus Lactobaccilus. The manufacture of this toothpaste is motivated by the desire of researchers to facilitate the public to use natural ingredients of green tea catechins whose result effectiveness against cariogenic bacteria was directly tested inhibition. This study is to find the right formula composition for greentea catechins toothpaste based on the result of the inhibition properties of greentea cathecins against tostreptococcus mutans dan lactobacillus acidophilus. The manufacture of greentea catechins toothpaste was after making catechins extracts and testing minimal inhibition concentration (MIC and minimal bactericidal concentration (MBC using liquid dilution method. The toothpaste was then made according to the result of MIC. The toothpaste’s flavonoid and polyphenol total contain was measured; then the inhibition property of the toothpaste to was measured using diffusion method with wells as the sample reservoar for streptococus mutans dan lactobacilus acidophilus. It is found that the toothpaste contains

  12. Pengaruh Fermentasi Bakteri Asam Laktat Terhadap Sifat Fisikokimia Tepung Gadung Modifikasi (Dioscorea hispida

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    R. Haryo Bimo Setiarto

    2016-06-01

    Full Text Available Yam (Dioscorea hispida is one of the tubers belonging to the family dioscoreaceae. Yam tubers not only have high content of carbohydrate, but also contain some toxic compounds such as: cyanogenic glycosides, alkaloids dioscorin, dehydrodioscorin, saponin and sapogenin. Fermentation of yam tubers can affected for physicochemical and amylography characteristics of modified yam flour and reduced toxic compounds. This study was aimed to determine effect of lactic acid bacteria (LAB fermentation on the physicochemical properties and characteristics of yam flour amilography modification. From the 15 isolates of Lactobacillus plantarum had been selected two isolate (L. plantarum B291 and B307 with the highest amylase enzyme activity to be used as starter fermentation to produce modified yam flour. Fermentation of LAB could reduce levels of HCN on modified yam flour, although decreased levels of HCN was not significant with requirements of SNI. Fermentation of LAB increased levels of protein, fat and lactic acid, but decreased pH value and carbohydrate content in modified yam flour. Based on results of amylography analysis, control of yam flour with shredded without fermentation had the best gelatinization profile because it most resistant about heating.ABSTRAKGadung (Dioscorea hispida merupakan salah satu jenis umbi-umbian yang tergolong dalam family Dioscoreaceae.  Ubi gadung memiliki kandungan karbohidrat yang tinggi, akan tetapi juga mengandung beberapa senyawa racun berupa glikosida sianogenik, alkaloid dioscorin, dehydrodioscorin, saponin dan sapogenin yang berbahaya bagi kesehatan. Fermentasi umbi gadung dapat mempengaruhi sifat fisikokimia dan amilografi tepung gadung modifikasi serta menurunkan senyawa toksiknya. Penelitian ini bertujuan untuk mengetahui pengaruh bakteri asam laktat (BAL penghasil amilase terhadap sifat fisikokimia dan amilografi tepung gadung modifikasi. Sebanyak 15 isolat Lactobacillus plantarum telah diseleksi, sehingga

  13. Identifikace PHA produkujících bakterií pomocí nástrojů molekulární biologie

    OpenAIRE

    Gajdová, Barbora

    2017-01-01

    Tato diplomová práce se zabývá identifikací bakterií, které jsou schopny produkce polyhydroxyalkanoátů (PHA). Mezi testovanými bakteriemi byli převážně zástupci rodu Pseudomonas, Lactobacillus, Bifidobacterium, dále vzorky z termofilní kultury a vzorky z přírodních zdrojů. Bakterie byly testovány pomocí molekulárně biologické metody PCR. Byla analyzována amplifikace genu kódujícího PHA syntázu (phaC). V první reakci byl detekován jak phaC gen zodpovědný za syntézu PHA, tak současně i 16S rRNA...

  14. UJI ZONA HAMBAT EKSTRAK DAUN PUTRI MALU (Mimosa pudica TERHADAP BAKTERI Staphylococcus aureus DAN Methicillin-resistant Staphylococcus aureus (MRSA SECARA IN VITRO

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    Nyoman Ririn Chandrika Sari

    2015-04-01

    Full Text Available Resistensi Staphylococcus aureus dan MRSA terhadap antibiotika spektrum luas mendorong berbagai penelitian untuk menemukan senyawa aktif yang sensitif dan efektif dalam menghambat pertumbuhan bakteri.Penelitian ini bertujuan untuk mengetahui efek penghambatan ekstrak daun putri malu (Mimosa pudica terhadap pertumbuhan bakteri Staphylococcus aureus dan MRSA.Penelitian terhadap aktivitas antimikrobial ekstrak daun putri malu dilakukan dengan metode agar difusi cakram dengan menggunakan metode Kirby-Bauer.Suspensi bakteri disesuaikan dengan standar kekeruhan Mc Farland 0.5. Biakan bakteri dalam cawan petri masing-masing diberikan 6 perlakuan, yaitu kontrol positif (amoxicillin atau vancomycin, kontrol negatif (alkohol, serta ekstrak daun putri malu dengan konsentrasi 25 mcg/ml, 50 mcg/ml, 75 mcg/ml dan 100 mcg/ml. Pertumbuhan Staphylococcus aureus dihambat secara signifikan oleh ekstrak daun putri malu, dengan efek inhibisi pada semua konsentrasi secara signifikan lebih baik dibandingkan dengan kontrol positif (p<0.05. Zona inhibisi Staphylococcus aureus pada konsentrasi 25 mcg/ml adalah 28.86 mm dan telah memenuhi kriteria sebagai antimikrobial sensitif berdasarkan Clinical and Laboratory Standard Institute (CLSI. Inhibisi pertumbuhan MRSA secara signifikan terjadi pada semua konsentrasi ekstrak daun putri malu dibandingkan dengan kontrol negatif (p=0.00. Zona inhibisi terbesar ditemukan pada konsentrasi 100 mcg/ml dengan diameter sebesar 14.16 mm dan memiliki efek antimikrobial sebanding dengan vancomycin dalam menghambat pertumbuhan MRSA (p=0.186. Hasil uji agar difusi cakram menunjukkan bahwa senyawa aktif dalam ekstrak daun putri malu memiliki aktivitas antimikrobial yang tinggi terhadap Staphylococcus aureus dan MRSA secara in vitro.

  15. Ba incorporation in benthic foraminifera

    NARCIS (Netherlands)

    de Nooijer, L.J.; Brombacher, Anieke; Mewes, A.; Langer, Gerald; Nehrke, G.; Bijma, Jelle; Reichart, G.J.

    2017-01-01

    Barium (Ba) incorporated in the calcite of many foraminiferal species is proportional to the concentration of Ba in seawater. Since the open ocean concentration of Ba closely follows seawater alkalinity, foraminiferal Ba ∕ Ca can be used to reconstruct the latter. Alternatively, Ba ∕ Ca from

  16. Alpha decay of 114Ba

    International Nuclear Information System (INIS)

    Mazzocchi, C.; Janas, Z.; Batist, L.; Belleguic, V.; Doering, J.; Kapica, M.; Kirchner, R.; Roeckl, E.; Gierlik, M.; Zylicz, J.; Mahmud, H.; Schmidt, K.; Woods, P.J.

    2003-01-01

    The neutron-deficient isotope 114 Ba was produced in a fusion evaporation reaction at the GSI On-Line Mass Separator. We measured the α-particle energy of 114 Ba, the half-life of its daughter nucleus 110 Xe, and the α-decay branching ratios for 114 Ba, 110 Xe and 106 Te. (orig.)

  17. Penurunan Kadar IL-1β Makrofag Terpapar Agregat Bakteri Actinomycetemcomitans setelah Pemberian Minyak Atsiri Temu Putih

    Directory of Open Access Journals (Sweden)

    Juni Handajani

    2015-12-01

    Full Text Available Kunci regulator terhadap respons inflamasi diketahui melalui aktivasi interleukin-1β (IL-1β. Makrofag merupakan sel fagosit mononuklear berperan dalam sistem imun innate dan adaptif. Sitokin yang disekresikan makrofag sebagai respons terhadap patogen antara lain IL-1, IL-6, IL-12, TNF-α, dan chemokine. Minyak atsiri temu putih (Curcuma zedoaria Rosc. diduga memiliki efek anti inflamasi. Tujuan penelitian ini adalah untuk mengetahui kadar IL-1β pada makrofag terekspose aggregat bakteri actinomycetemcomitans setelah pemberian minyak atsiri temu putih. Subjek penelitian adalah 10 ekor tikus Wistar jantan yang dibagi menjadi 2 kelompok (perlakuan dan kontrol, masing-masing kelompok terdiri atas 5 ekor. Kelompok perlakuan diberi minum minyak atsiri temu putih dosis 30,6 μl/ml dan kelompok kontrol diberi aquabides selama 14 hari. Gingiva anterior rahang bawah tikus diolesi A.actinomycetemcomitans sebanyak 100 μl dalam CMC 2% pada hari ke-7 setelah pemberian minum bahan uji dan kontrol selama 7 hari. Pada hari ke-15, tikus pada masing-masing kelompok dianestesi lalu makrofag dikoleksi dari cairan peritoneal. Kadar IL-1β makrofag diukur menggunakan ELISA kit (R&D Systems, USA, selanjutnya data dianalisis menggunakan uji-t. Hasil penelitian menunjukkan terdapat penurunan kadar IL-1β setelah perlakuan. Perbandingan kelompok perlakuan dan kontrol menunjukkan perbedaan bermakna (p < 0,05. Disimpulkan bahwa minyak atsiri temu putih kemungkinan memiliki efek anti inflamasi melalui penurunan kadar IL-1β makrofag. IL-1β level of macrophage exposed to A. actinomycetemomitans decreases after administration Curcuma Zedoaria volatile oil. Activation of interleukin-1β (IL-1β is a key regulator of the inflammatory response. Macrophage is a phagocytic mononuclear cell that plays an important role in innate and adaptive immune response. The cytokine secreted by macrophages in response to pathogen are IL-1, IL-6, IL-12, TNF-α and chemokine

  18. Uji Daya Hambat Sabun Cair Cuci Tangan pada Restoran Waralaba di Kota Padang Terhadap Pertumbuhan Bakteri Escherichia coli dan Staphylococcus aureus Secara In Vitro

    Directory of Open Access Journals (Sweden)

    Anisha Fazlisia

    2014-09-01

    Full Text Available AbstrakSabun cair cuci tangan terbukti dapat menghambat pertumbuhan bakteri Escherichia coli dan Staphylococcus aureus. Sebagian besar restoran waralaba di Kota Padang menyediakan sabun cair cuci tangan yang telah diencerkan. Proses pengenceran mengubah kemampuan sabun dalam menghambat pertumbuhan bakteri. Penelitian bertujuan untuk menguji daya hambat sabun cair cuci tangan pada restoran waralaba di Kota Padang terhadap pertumbuhan E. coli dan S. aureus. Sampel diambil dari empat restoran waralaba dan diuji dengan metode difusi. Hasil penelitian menunjukkan bahwa keempat sabun dapat menghambat pertumbuhan S. aureus namun hanya sebagian yang memiliki daya hambat terhadap E. coli. Median daya hambat pertumbuhan E. coli dan S. aureus pada setiap periode yaitu 0, 7.4, 7.3 dan 0, 26.1, 23.3. Nilai maksimum daya hambat pertumbuhan E.coli dalam tiga periode yaitu 19.5, 35.4, 27.1 dan 20.7, 40.2, 36.6 untukS. aureus. Daya hambat minimum terhadap kedua bakteri adalah 0.00. Hal tersebut dapat dipengaruhi komposisi dan konsentrasi antiseptik, antibakteri, pH sabun, pengenceran dan struktur dinding sel bakteri. Disimpulkan bahwa sabun cair cuci tangan yang diuji memiliki kemampuan lebih besar dalam menghambat pertumbuhan S.aureus daripada E.coli.Kata kunci: sabun cair cuci tangan, restoran, pengenceran, uji daya hambat, pertumbuhan bakteriAbstractLiquid hand soaps proved to inhibit Escherichia coli and Staphylococcus aureus bacterial growth. In Padang, most of Restaurants provide diluted liquid hand soaps. Research found dilution changed soap ability to inhibit bacterial growth. The purpose of this study was to examine the ability of Padang City Restaurants’ liquid hand soaps to inhibit E. coli and S. aureus bacterial growth. The samples were taken from four restaurants and examined by using diffusion method. The results showed all of them could inhibit S. aureus but only a half inhibited Escherichia coli bacterial growth. Median for E. coli and S

  19. SELEKSI DAN IDENTIFIKASI BAKTERI ENDOFIT POTENSIAL PENGHASIL ENZIM PROTEASE DARI TAMAN NASIONAL GUNUNG HALIMUN - (The Selection and Identification of Potential Endophyte Bacteria as Protease Enzyme Producer from Halimun Mount National Park

    Directory of Open Access Journals (Sweden)

    Ruth Melliawati

    2016-12-01

    Full Text Available Endophytic bacteria have an equal chance to bacteria that live outside the plant tissue as potential bacteria. The selection has done towards 326 bacterial endophyte isolates. This research aimed to find and identify proteolytic potential isolates. The proteolytic selection of endophytic bacteria had done using solid skim milk. The capability of endophytic bacteria to agglomerate milk was tested using liquid skim milk which incubated for 7 days at room temperature. Enzyme production of four selected isolates was made through fermentation in GYS medium. The results showed that 86 isolates have proteolytic potential. Isolate HL.29B.63 had highest protease enzymes activity (65.918 U/mL. Medium optimization was able to increase the enzyme activity into 89.94% (125.04 U/mL. The analysis used 16s rDNA showed that isolate HL.29B.63 was Bacillus amyloliquefacient subs. plantarum strain FZB42.Keywords: endophytic bacteria, fermentation, identification, protease, selection ABSTRAKBakteri endofit mempunyai peluang yang sama dengan bakteri yang hidup diluar jaringan tanaman sebagai bakteri potensial. Seleksi dilakukan terhadap 326 isolat bakteri endofit. Tujuan penelitian ini adalah mencari isolat yang berpotensi proteolitik dan mengidentifikasinya. Seleksi proteolitik terhadap bakteri endofitik menggunakan skim milk padat. Uji kemampuan bakteri endofitik dalam menggumpalkan susu menggunakan medium skim milk cair yang diinkubasi selama 7 hari pada suhu ruang. Produksi enzim terhadap empat isolat terseleksi dilakukan melalui fermentasi dalam medium GYS. Hasilnya menunjukkan bahwa 86 isolat mempunyai potensi proteolitik. Isolat HL.29B.63 mempunyai aktif enzim protease tertinggi (65,918 U/mL. Optimasi medium dapat meningkatkan aktivitas enzim sebesar 89,94% (125,04 U/mL. Analisis menggunakan 16s rDNA menunjukkan bahwa isolat HL.29B.63 adalah Bacillus amyloliquefaciens subs. plantarum strain FZB42.Kata kunci: bakteri endofit, fermentasi, identifikasi, protease

  20. Decay /sup 133/Ba

    Energy Technology Data Exchange (ETDEWEB)

    Singh, K; Hasiza, M L; Grewal, B S; Sahota, H S

    1982-07-01

    The relative gamma ray intensities of transitions in the decay of /sup 133/Ba have been measured using an intrinsic Ge detector. The electron capture branching ratios have been determined for 81, 161, 384 and 437 keV levels. The attenuation effect of long half-life of 81 keV levels has been studied in solid and liquid media. The electron capture decay has been investigated by changing the concentration of ethylene-diamine-tetraacetic acid (EDTA) environment. The 5/2/sup +/ yields 5/2/sup +/ 79.67 keV transition has an E0 to E2 intensity qsub(k)sup(2) <= 0.31. 10 refs., 4 figures.

  1. Pengaruh pemberian ekstrak meniran merah (Phyllanthus urinaria terhadap penekanan jumlah limfosit pada organ timus mencit balb/C yang diinfeksi bakteri Salmonella thypi

    Directory of Open Access Journals (Sweden)

    IFANDARI

    2012-05-01

    Full Text Available Ifandari, Suranto, Wuryaningsih YNS. 2012. Pengaruh pemberian ekstrak meniran merah (Phyllanthus urinaria terhadap penekanan jumlah limfosit pada organ timus mencit balb/C yang diinfeksi bakteri Salmonella thypi. Bioteknologi 9: 1-6. Meniran merah merupakan salah satu anggota dalam genus Phyllanthus. Anggota dalam genus ini memiliki variasi karakter morfologi dimana beberapa diantaranya telah digunakan sebagai tanaman obat tradisional. Meniran merah digunakan dalam pene- litian sebagai diuretik, hipoglikemik, antihepatitis-B dan anti kanker. Kemanfaatan tanaman ini sebagaii immunomodulator belum digali. Penelitian ini bertujuan untuk mengetahui pengaruh pemberian meniran merah terhadap jumlah limfosit pada organ timus mencit Balb/C yang diinfeksi bakteri Salmonella thypi dan mengetahui pengaruh variasi dosis ekstrak meniran merah terhadap jumlah limfositnya. Penelitian ini menggunakan rancangan the post test-only control group terhadap 48 ekor mencit Balb/C yang terbagi dalam 8 kelompok dan dilakukan selama 10 hari. Kelompok kontrol negatif, kontrol positif, kelompok perlakuan dengan variasi dosis masing-masing 3x 0,065 mg/hr, 3x0,130 mg/hr dan 3x0,260 mg/hr untuk tiap jenis ekstrak meniran merah dan hijau. Mencit diinfeksi pada hari ke-4 S. typhi dan hari ke-11 dikorbankan. Limfosit diisolasi dari organ timus, kemudian dihitung jumlahnya. Data dianalisis dengan T test untuk melihat perbedaanya dan data dalam kelompok meniran merah dilakukan uji anava. Pemberian ekstrak meniran merah menekan jumlah limfosit mendekati keadaan normal. Variasi penambahan dosis ekstrak meniran merah tidak mepengaruhi penurunan jumlah limfosit.

  2. The BaBar Mini

    International Nuclear Information System (INIS)

    Brown, David N.

    2003-01-01

    BaBar has recently deployed a new event data format referred to as the Mini. The mini uses efficient packing and aggressive noise suppression to represent the average reconstructed BaBar event in under 7 KBytes. The Mini packs detector information into simple transient data objects, which are then aggregated into roughly 10 composite persistent objects per event. The Mini currently uses Objectivity persistence, and it is being ported to use Root persistence. The Mini contains enough information to support detailed detector studies, while remaining small and fast enough to be used directly in physics analysis. Mini output is customizable, allowing users to both truncate unnecessary content or add content, depending on their needs. The Mini has now replaced three older formats as the primary output of BaBar event reconstruction. A reduced form of the Mini will soon replace the physics analysis format as well, giving BaBar a single, flexible event data format covering all its needs

  3. The BaBar mini

    International Nuclear Information System (INIS)

    Brown, David N.; BaBar Collaboration

    2003-01-01

    BaBar has recently deployed a new event data format referred to as the Mini. The mini uses efficient packing and aggressive noise suppression to represent the average reconstructed BaBar event in under 7 KBytes. The Mini packs detector information into simple transient data objects, which are then aggregated into roughly 10 composite persistent objects per event. The Mini currently uses Objectivity persistence, and it is being ported to use Root persistence. The Mini contains enough information to support detailed detector studies, while remaining small and fast enough to be used directly in physics analysis. Mini output is customizable, allowing users to both truncate unnecessary content or add content, depending on their needs. The Mini has now replaced three older formats as the primary output of BaBar event reconstruction. A reduced form of the Mini will soon replace the physics analysis format as well, giving BaBar a single, flexible event data format covering all its needs

  4. Optimasi Konsentrasi Fruktooligosakarida untuk Meningkatkan Pertumbuhan Bakteri Asam Laktat Starter Yoghurt (CONCENTRATION OPTIMIZATION OF FRUCTOOLIGOSACCHARIDES TO INCREASE GROWTH OF LACTIC ACID BACTERIA YOGHURT STARTER

    Directory of Open Access Journals (Sweden)

    Raden Haryo Bimo Setiarto

    2017-09-01

    Full Text Available Fructooligosaccharides are prebiotic source that widely used in food products, such as: fermented milk and infant formula. Prebiotics are food components that cannot be digested in the digestive tract enzymatically. However, they can be fermented by probiotic bacteria in the colon. This study aimed to determine the optimum concentrations of fructooligosaccharides in order to increase the growth of lactic acid bacteria yogurt starter (Lactobacillus acidophillus, Lactobacillus bulgaricus, Streptococcus thermophillus. Optimation concentration of fructooligosaccharides on the growth of Lactobacillus acidophilus, Lactobacillus bulgaricus, Streptococcus thermophillus can be determined based on OD (optical density, TPC (Total Plate Count, total lactic acid content and pH value. Suplementation of fructooligosaccharides 1 % (w/v on the media MRSB increased significantly the growth of L. acidophilus, L.bulgaricus, S. thermophilus. Furthermore, L. acidophilus, L. bulgaricus and S. thermophilus experienced exponential growth phase during incubation period from 6 to 18 hours. Fermentation of L. acidophilus, L. bulgaricus, S. thermophilus in MRSB medium supplemented by fructooligosaccharides decreased the pH value of the formation of organic acids from 6.00 to 4.00. ABSTRAK Fruktooligosakarida adalah sumber prebiotik yang banyak digunakan dalam produk pangan olahan seperti susu fermentasi dan susu formula. Prebiotik adalah komponen bahan pangan fungsional yang tidak dapat dicerna di dalam saluran pencernaan secara enzimatik sehingga akan difermentasi oleh bakteri probiotik dalam usus besar. Penelitian ini bertujuan menentukan konsentrasi optimum fruktooligosakarida untuk meningkatkan pertumbuhan bakteri asam laktat starter yoghurt (Lactobacillus acidophillus, Lactobacillus bulgaricus, Streptococcus thermophillus. Konsentrasi optimum fruktooligosakarida pada pertumbuhan Lactobacillus acidophilus, Lactobacillus bulgaricus, Streptococcus thermophillus dapat

  5. AHP 45: REVIEW: PHYUR BA

    Directory of Open Access Journals (Sweden)

    'Brug mo skyid འབྲུག་མོ་སྐྱིད། (Zhoumaoji 周毛吉

    2017-03-01

    Full Text Available Mkha' mo rgyal was born in Dgon gong ma Village, 'Ba' (Tongde County, Mtsho lho (Hainan Tibetan Autonomous Prefecture, Mtsho sngon (Qinghai Province. While attending the Tibetan Studies College of Mtsho sngon Nationalities University she began writing. In addition to editing and translating teaching materials for primary and secondary schools, she has also published short stories and poetry (Mkha' mo rgyal, 2015. Phyur ba is the first Tibetan women's novel (Robin 2016:86 and was recognized as an Outstanding Work by the Qinghai Writers Guild in 2014 (Duojiecairang and Limaoyou 2014. 1 The name, which translates as 'dried cheese' is a food eaten daily by many Tibetans. Made from fermented milk without cream, it is dried in the sun by women in pastoral areas. Both sweet and sour, phyur ba brings to mind the happiness and sadness, ups and downs, laughter and tears that life brings. ...

  6. PERAN BAKTERI DALAM MENGUBAH ARSEN ANORGANIK MENJADI ARSEN ORGANIK DI PERAIRAN (The Roles of Bacteria in Modifying Inorganic Arsen to Organic Arsen in Waters

    Directory of Open Access Journals (Sweden)

    Eko Sugiharto

    2006-11-01

    Full Text Available ABSTRAK Tujuan penelitian ini adalah mengetahui peranan bakteri Esherichia coli dan Pseudomonas sp. dalam menubah spesies arsen. Arsenik dikenal sebagai salah satu unsur kimia yang mempunyai toksisitas tinggi. Analisis mentenai spesiasi arsen yang terkandung dalam perairan dilakukan dengan metode gabungan Kromatografi cair Kinerja Tinggi – Spektrometri Serapan Atom (HPLC-AAS. Untuk mengetahui peranan bakteri E.Coli dan Pseudomnonas sp. maka dilakukan tiga perlakuan, yaituperlakuan dengan variasi media pertumbuhan, variasi pH, dan variasi suhu inkubasi. Media pertumbuhan yant ditunakan yai5u air, l – metionin, nutrient broth, czapek dox, dan garam mineral. Variasi pH dilakukan pada pH 4, 5, 6, 7, 8, dan 9, sedangkan variasi suhu silakukan pada 25oC sampai dengan 35oC. Hasil penelitian menunjukkan bahwa ada peningkatan persentase jumlah As (V yang terenduksi menjadi As (III dalam media garam mineral pH7 dengan suhu optimum 35oC. Enzim yang dihasilkan Pseudomonas sp. dapat mereduksi As (V menjadi As (III pada media garam mineral pH 8 dan optimum pada semua variasi suhu. Keseluruhan hasil penelitian menunjukkan bahwa bakteri E. coli dan Peseudomonas sp. dapat meningkatkan toksisitas arsen di perairan karena kedua bakteri dapat mereduksi As (V menjadi As (III pada pH dan temperatur optimum.   ABSTRACT The aim of this research was to know the roles of Escharichia coli and Pseudomonas sp. in arsenic speciation. Arsenic has been known as highly toxic chemical element. The analysis towards arsenic speciation which is contained in waters was done by using High Pressure Liquid Chromatography (HPLC – Atomic Absorption Spectrometry (AAS coupling method. The observation towards the roles of E.coli and Pseudomonas.sp was done by variating the growth medium, pH and incubation temperature. The growth medium used in this observation were later, l – metionin, nutrient broth, czapek dox and mineral salt. The variation of pH was carried out at pH of 4

  7. TRANSITIVITY AND THE BA CONSTRUCTION

    Directory of Open Access Journals (Sweden)

    Pei-Jung Kuo

    2010-06-01

    Full Text Available In this paper, I discuss the legitimacy of positing a Transitivity Projection (= TrP cf. Bowers 1993, 1997, 2001 and 2002 in the BA construction in Mandarin Chinese. BA has been proposed to be a semantically-bleached verb, inserted in the v position (Huang 1997 and Lin 2001. Several pieces of evidence such as manner adverbial placement (cf. Huang, Li and Li 2009 and GEI-insertion (cf. Tang 2001 indicate that there must be a functional projection between the vP and VP to host the BA NP. I propose that a TrP is probably the most apt candidate for the XP. I also argue, in contrast to the proposal by Huang, Li and Li (2009, that the present proposal which employs a TrP captures most of the properties of the BA construction. A comparison with the structure of the BEI construction also shows that the TrP proposal fits into the general picture of current linguistic theory on transitive constructions without extra stipulations.

  8. Bakteri Legionella pneumophila Terdeteksi pada Air Kolam Renang di Kota Surabaya dengan Nested Polymerase Chain Reaction (LEGIONELLA PNEUMOPHILA BACTERIADETECTED IN SWIMMING POOL WATER OF SURABAYA BY USING NESTED POLYMERASE CHAIN REACTION

    Directory of Open Access Journals (Sweden)

    Eduardus Bimo Aksono

    2017-06-01

    Full Text Available Legionella pneumophila is a Gram-negative bacillus that causes nosocomial and community-acquired pneumonia. The aim of this research was to detect the presence of bacteria of L. pneumophila species in the swimming pools water of Surabaya city by using nested Polymerase Chain Reaction (PCR assay of a specific gene for L. pneumophila (mip gene. This study used purposive sampling method. A total of 10 water samples were collected from five swimming pools consisting of 200 mL water for each swimming pool. The results showed that of 10 samples tested by nested PCR, one sample was positive for L. pneumophila, and nine samples were negative. L. pneumophila were found in pool water samples with a higher temperature (>30ºC.Serogrouping analysis of positive sample that L. pneumophila bacteria detected in the water sample of swimming pool in Surabaya was L. pneumophila serogroup 9 (98% and serogroup 10 (98%. L. pneumophila detection of bacteria is expected to raise the awareness of physician and microbiologists about the transmission of L. pneumophila and will also be useful for controlling the agents. ABSTRAK Legionella pneumophila adalah bakteri Gram-negatif berbentuk batang yang dapat menyebabkan penyakit nosokomial dan pneumonia. Tujuan penelitian ini adalah untuk mendeteksi keberadaan bakteri L. pneumophila pada air kolam renang di Kota Surabaya dengan menggunakan nested Polymerase Chain Reaction (PCR berbasis gen spesifik L. pneumophila (mip gene. Penelitian ini menggunakan metode purposive sampling. Sebanyak sepuluh sampel diambil dari lima kolam renang. Sampel diambil sebanyak 200 mL dari air kolam renang di setiap lokasi. Hasil dari 10 sampel yang diuji menggunakan nested PCR, satu sampel menunjukkan hasil positif untuk L.pneumophila, dan sembilan sampel menunjukkan hasil negatif. Bakteri L. pneumophila ditemukan pada sampel air kolam dengan suhu yang lebih tinggi (>30ºC. Satu sampel positip tersebut ketika dilanjutkan terhadap analisis serogrup

  9. BaMa / Raivo Juurak

    Index Scriptorium Estoniae

    Juurak, Raivo, 1949-

    2002-01-01

    Eesti ülikoolide üleminekust 3+2 süsteemile. Lühend BaMa on tulnud kasutusele seoses Euroopa ülikoolide õppekavade reformimisega ning tähistab õppekava, kus esimese astme läbimise järel omandatakse bakalaureuse- ja teise järel magistrikraad. Õppekavade tüüpidest Eesti ja Euroopa Liidu kõrgkoolides ning Bologna deklaratsioonist

  10. Bakterier og biopolitik

    DEFF Research Database (Denmark)

    Jørgensen, Jens Lohfert

    2017-01-01

    Around the year 1900, a number of prominent authors depict a changing world, phenomenologically and psychologically, as well as socially and politically, via bacteria. This endeavor moves their work in the direction of modernism. Drawing on Robert Esposito’s work on the interrelations between...... biopolitics, community and immunity, and on Jane Bennett’s notion of “vibrant matter”, this article discusses one of these works, Joseph Conrad’s 1897 novel The Nigger of the ‘Narcissus’, focusing on its depiction of social dynamics and the material anchorage of these dynamics....

  11. Perbandingan Efektivitas Daya Hambat Kotrimoksazol Generik dan Paten terhadap Pertumbuhan Bakteri Escherichia coli sebagai Penyebab Infeksi Saluran Kemih secara In Vitro

    Directory of Open Access Journals (Sweden)

    Puti Anggun Sari

    2015-01-01

    Full Text Available AbstrakInfeksi saluran kemih merupakan salah satu infeksi yang sering ditemukan setelah infeksi saluran napas. Penyebab terbanyak infeksi saluran kemih adalah Escherichia coli. Kotrimoksazol merupakan kombinasi dari dua obat yaitu trimetoprim dan sulfametoksazol serta salah satu contoh antibiotik yang merupakan first-line therapy untuk infeksi saluran kemih. Kotrimoksazol terbagi menjadi dua jenis obat yaitu obat generik dan paten. Akan tetapi, belakangan ini penggunaan obat generik mulai menurun di masyarakat dan masyarakat cenderung meragukan kualitasnya. Padahal masyarakat yang akan diuntungkan jika mengetahui mutu obat generik tidak kalah dengan obat paten. Tujuan dari penelitian ini adalah untuk membandingkan efektivitas daya hambat kotrimoksazol generik dan paten terhadap pertumbuhan bakteri Escherichia coli sebagai penyebab infeksi saluran kemih secara in vitro. Penelitian ini merupakan penelitian analitik eksperimental dengan desain cross-sectional study. Penelitian ini menggunakan 19 sampel isolat bakteri dari pasien infeksi saluran kemih yang disebabkan oleh Escherichia coli di RSUP Dr. M. Djamil yang ditentukan rumus minimal adequate sample size menggunakan metode difusi cakram dan dilihat perbandingan antara zona bebas kuman yang dibentuk oleh obat generik dan paten tersebut. Data yang diperoleh akan diolah secara statistik dengan uji hipotesis t-independent test. Hasil penelitian menunjukkan bahwa pada 17 sampel tidak didapatkan zona bebas kuman baik pada kotrimoksazol generik atau paten. Sedangkan pada 2 sampel lainnya didapatkan zona bebas kuman pada kedua obat kotrimoksazol generik dan paten. Setelah dilakukan analisis statistik menggunakan SPSS dengan uji t-independent test didapatkan bahwa tidak terdapat perbedaan bermakna antara sensitivitas bakteri Escherichia coli penyebab infeksi saluran kemih terhadap kotrimoksazol generik dan paten. Sedangkan resistensi yang terjadi pada 17 sampel lain diduga disebabkan penggunaan

  12. Phase equilibria in the BaUO3-BaZrO3-BaMoO3 system

    International Nuclear Information System (INIS)

    Kurosaki, Ken; Yamanaka, Shinsuke; Matsuda, Tetsushi; Uno, Masayoshi; Yamamoto, Kazuya; Namekawa, Takashi

    2002-01-01

    The phase equilibria in the pseudo-ternary BaUO 3 -BaZrO 3 -BaMoO 3 system were studied to understand the thermochemical properties of the perovskite type gray oxide phase in high burnup MOX fuel. Thermodynamic equilibrium calculation for the system was performed by using a Chem Sage program under the various oxygen potentials. Solid solutions existing in the system were treated by an ideal solution model. The present calculation results well agreed with the previous reported post irradiation examination results, showing that BaMoO 3 was scarcely included in the gray oxide phase. (author)

  13. Mass spectrometric determination of stability of gaseous BaMoO2, Ba2MoO4, Ba2MoO5, Ba2Mo2O8 molecules

    International Nuclear Information System (INIS)

    Kudin, L.S.; Balduchchi, Dzh.; Dzhil'i, G.; Gvido, M.

    1982-01-01

    During the mass spectrometric investigation of BaCrO 4 evaporation Cr + , Ba + , BaO + main ions are recorded as well as BaMoO 4 + , BaMoO 3 + , BaMoO 2 + , BaMoO + , BaMoO 4 + , Ba 2 MoO 5 + , BaMo 2 O 8 + ions - the products of ionization of three-component (Ba, Mo, M) molecules, forming as a result of substance chemical interaction with the material of an effusion cell (Mo). Heats of formation of BaMoO 2 , Ba 2 MoO 4 , Ba 2 MoO 5 and Ba 2 Mo 2 O 8 molecules which constituted - 577+-70, -1343+-115, -1464+-70, -2393+-90 k J/mol respectively are determined on the base of the analysis of curves of ionisation efficiency and of reaction heats Ba 2 MoO 5 =BaO+BaMoO 4 , ΔH 0 0 =322+-60 kJ/mol Ba 2 Mo 2 O 8 =2BaMoO 4 , ΔH 0 0 =351+-80 kJ/mol calculated with the use of third low of thermodynamics [ru

  14. BaBar Data Aquisition

    CERN Document Server

    Scott, I; Grosso, P; Hamilton, R T; Huffer, M E; O'Grady, C; Russell, J J

    1998-01-01

    The BaBar experiment at the Stanford Linear Accelerator Center is designed to perform a search for CP violation by analysing the decays of a very large sample of B and Bbar mesons produced at the high luminosity PEP-11 accelerator. The data acquisition system must cope with a sustained high event rate, while supporting real time feature extraction and data compression with minimal dead time. The BaBar data acquisition system is based around a common VME interface to the electronics read-out of the separate detector subsystems. Data from the front end electronics is read into commercial VME processors via a custom "personality card" and PCI interface. The commercial CPUs run the Tornado operating system to provide a platform for detector subsystem code to perform the necessary data processing. The data are read out via a non-blocking network switch to a farm of commercial UNIX processors. Careful design of the core data acquisition code has enabled us to sustain events rates in excess of 20 kHz while maintaini...

  15. Back-contacted BaSi

    NARCIS (Netherlands)

    Vismara, R.; Isabella, O.; Zeman, M.

    2017-01-01

    We present the optical investigation of a novel back-contacted architecture for solar cells based on a thin barium (di)silicide (BaSi2) absorber. First, through the analysis of absorption limits of different semiconducting materials, we show the potential of BaSi2 for

  16. Phonon dispersion curves of BCC Ba

    International Nuclear Information System (INIS)

    Mizuki, J.; Stassis, C.; Zarestky, J.

    1985-01-01

    Ba, as well as Sr and Ca, is a divalent alkaline earth metal. At room temperature and ambient pressure, the structure of Ba is bcc, whereas that of Sr and Ca is fcc. Under pressure, the bcc phase of Ba transforms to an hcp structure at 55 kbar. Also, at 37 kbar Ba becomes a superconductor with T/sub c/ = 0.06 K. These properties are highly dependent on the position of the d bands relative to the Fermi level. Experimental investigation of the elastic and lattice dynamical properties of these metals has been hindered by difficulties in growing single crystals. However, recently the authors were able to grow several single crystals of bcc Ba of sufficient volume for inelastic neutron scattering experiments. Some of the results are summarized here

  17. APLIKASI KOMBINASI KOMPOS JERAMI, KOMPOS AZOLLA DAN PUPUK HAYATI UNTUK MENINGKATKAN JUMLAH POPULASI BAKTERI PENAMBAT NITROGEN DAN PRODUKTIVITAS TANAMAN PADI BERRBASIS IPAT-BO

    Directory of Open Access Journals (Sweden)

    Ferina Rosiana

    2013-03-01

    Full Text Available Penelitian untuk mengetahui efek pemberian kombinasi kompos jerami dengan Azolla dan pupuk hayati majemuk terhadap peningkatan populasi bakteri penambat N dan produktivitas tanaman padi dengan teknologi IPAT-BO dilaksanakan dari bulan April hingga Juli 2012 di kebun percobaan Fakultas Pertanian, Universitas Padjadjaran, Jatinangor, dengan ketinggian + 740 m dpl. Penelitian ini menggunakan rancangan acak kelompok faktor tunggal dengan dua belas perlakuan dan tiga kali ulangan. Perlakuan terdiri dari (A tanpa kompos jerami, (B kompos jerami 2,5 ton ha-1, (C kompos jerami 5 ton ha-1, (D kompos Azolla 0,5 ton ha-1, (E kompos jerami 2,5 ton ha-1 + kompos Azolla 0,5 ton ha-1, (F kompos jerami 5 ton ha-1 + kompos Azolla 0,5 ton ha-1, (G pupuk hayati 400 g ha-1, (H kompos jerami 2,5 ton ha-1 + pupuk hayati 400 g ha-1, (I kompos jerami 5 ton ha-1 + pupuk hayati 400 g ha-1, (J kompos Azolla 0,5 ton ha-1 + pupuk hayati 400 g ha-1, (K kompos jerami 2,5 ton ha-1 + kompos Azolla 0,5 ton ha-1 + pupuk hayati 400 g ha-1, (L kompos jerami 5 ton ha-1 + kompos Azolla 0,5 ton ha-1 + pupuk hayati 400 g ha-1.Aplikasi perlakuan kompos jerami, kompos Azolla dan pupuk hayati majemuk memberikan pengaruh terhadap populasi penambat N (Azotobacter sp. dan Azospirilium sp. dan produktifitas tanaman padi. Aplikasi kompos jerami 2,5 ton ha-1 dengan pupuk hayati 400 g ha-1 memberikan hasil GKP yaitu 64,39 g tanaman-1 (6,13 ton ha-1. Kata kunci: IPAT-BO, kompos Azolla, kompos jerami, pupuk hayati.

  18. Polarizabilities of Ba and Ba2: Comparison of molecular beam experiments with relativistic quantum chemistry

    International Nuclear Information System (INIS)

    Schaefer, Sascha; Mehring, Max; Schaefer, Rolf; Schwerdtfeger, Peter

    2007-01-01

    The dielectric response to an inhomogeneous electric field has been investigated for Ba and Ba 2 within a molecular beam experiment. The ratio of the polarizabilities per atom of Ba 2 and Ba is determined to be 1.30±0.13. The experimental result is compared to a high level ab initio quantum chemical coupled cluster calculation with an energy-consistent scalar relativistic small-core pseudopotential for Ba. For the barium atom a polarizability of 40.82 A 3 is obtained and the isotropic value of the polarizability calculated for Ba 2 is 97.88 A 3 , which is in good agreement with the experimental results, demonstrating that a quantitative understanding of the interaction between two closed-shell heavy element metal atoms has been achieved

  19. Antibacterial Activity Test of Nudibranches Polka - Dot (Jorunna funebris (Gastropods : Molusc Extract Against Multi(Aktivitas Antibakteri Ekstrak Nudibranch Polka-Dot (Jorunna funebris (Gastropoda : Moluska Terhadap Bakteri Multidrug Resistant (MDR

    Directory of Open Access Journals (Sweden)

    Delianis Pringgenies

    2015-12-01

    Full Text Available Terjadinya resistensi antibiotik menjadi permasalahan dalam dunia kesehatan. Peningkatan kemampuan patogen dalam menahan efek obat menyebabkan timbulnya resistensi. Beberapa bakteri patogen pada manusia dilaporkan telah mengalami resistensi terhadap lebih dari satu kelas antibiotik. Untuk mengatasi permasalahan tersebut, maka perlu dilakukan pencarian senyawa antibiotik baru yang lebih efektif dalam mengatasi permasalahan bakteri Multi-drug Resistant (MDR. Metabolit sekunder yang diproduksi oleh invertebrata laut  mempunyai prospek sebagai bahan obat dari laut. Nudibranch diduga mampu menghasilkan metabolit sekunder sebagai mekanisme pertahanan diri. Tujuan dari penelitian ini adalah untuk mengetahui fraksi dari ekstrak nudibranch Jorunna funebris yang menunjukkan bioaktivitas terhadap bakteri Multi-drug Resistant (MDR. Proses ekstraksi dilakukan dengan metode maserasi. Fraksinasi dengan Kromatografi Kolom Terbuka (KKT. Uji aktivitas antibakteri menggunakan metode difusi agar. Analisis komponen senyawa dengan GC-MS. Hasil penelitian menunjukkan bahwa 8 fraksi ekstrak nudibranch J. funebris menunjukkan aktivitas antibakteri. Hasil uji aktivitas menunjukkan fraksi I paling aktif terhadap 5 bakteri uji yaitu Klebsiella, Pseudomonas, Escherichia coli, Enterobacter 5 dan Enterobacter 10 dengan rata-rata zona hambatan secara berurutan sebesar 12,78 mm; 12,51 mm; 15,47 mm; 14,09 mm dan 12,46 mm. Fraksi II paling aktif terhadap bakteri Coagulase Negative Staphylococcus dengan rata-rata zona hambatan sebesar 12,70 mm. Analisis GC-MS menunjukkan bahwa dalam fraksi II terdapat senyawa 1-oktadekanol yang berpotensi sebagai antibakteri. Kata kunci : nudibranch, Jorunna funebris, antibakteri, multi-drug resistant, 1-oktadekanol Emergence of antibiotic resistance become a problems on medical world. Increasing pathogen ability to hold the antibiotic effect caused resistance. Several human-patogen bacteria were resistance to one or more classes of antibiotics

  20. The BaBar silicon vertex tracker

    International Nuclear Information System (INIS)

    Bozzi, C.; Carassiti, V.; Ramusino, A. Cotta; Dittongo, S.; Folegani, M.; Piemontese, L.; Abbott, B.K.; Breon, A.B.; Clark, A.R.; Dow, S.; Fan, Q.; Goozen, F.; Hernikl, C.; Karcher, A.; Kerth, L.T.; Kipnis, I.; Kluth, S.; Lynch, G.; Levi, M.; Luft, P.; Luo, L.; Nyman, M.; Pedrali-Noy, M.; Roe, N.A.; Zizka, G.; Roberts, D.; Barni, D.; Brenna, E.; Defendi, I.; Forti, A.; Giugni, D.; Lanni, F.; Palombo, F.; Vaniev, V.; Leona, A.; Mandelli, E.; Manfredi, P.F.; Perazzo, A.; Re, V.; Angelini, C.; Batignani, G.; Bettarini, S.; Bondioli, M.; Bosi, F.; Calderini, G.; Carpinelli, M.; Dutra, F.; Forti, F.; Gagliardi, D.; Giorgi, M.A.; Lusiani, A.; Mammini, P.; Morganti, M.; Morsani, F.; Paoloni, E.; Profeti, A.; Rama, M.; Rampino, G.; Rizzo, G.; Sandrelli, F.; Simi, G.; Triggiani, G.; Tritto, S.; Vitale, R.; Burchat, P.; Cheng, C.; Kirkby, D.; Meyer, T.; Roat, C.; Bona, M.; Bianchi, F.; Daudo, F.; Girolamo, B. Di; Gamba, D.; Giraudo, G.; Grosso, P.; Romero, A.; Smol, A.; Trapani, P.; Zanin, D.; Bosisio, L.; Ricca, G. Della; Lanceri, L.; Pompili, A.; Poropat, P.; Prest, M.; Rastelli, C.; Vallazza, E.; Vuagnin, G.; Hast, C.; Potter, E.P.; Sharma, V.; Burke, S.; Callahan, D.; Campagnari, C.; Dahmes, B.; Eppich, A.; Hale, D.; Hall, K.; Hart, P.; Kuznetsova, N.; Kyre, S.; Levy, S.; Long, O.; May, J.; Richman, J.; Verkerke, W.; Witherell, M.; Beringer, J.; Eisner, A.M.; Frey, A.; Grillo, A.; Grothe, M.; Johnson, R.; Kroeger, W.; Lockman, W.; Pulliam, T.; Rowe, W.; Schmitz, R.; Seiden, A.; Spencer, E.; Turri, M.; Wilder, M.; Charles, E.; Elmer, P.; Nielsen, J.; Orejudos, W.; Scott, I.; Walsh, J.; Zobernig, H.

    2000-01-01

    The BaBar Silicon Vertex Tracker (SVT) is designed to provide the high-precision vertexing necessary for making measurements of CP violation at the SLAC B-Factory PEP-II. The instrument consists of five layers of double-sided silicon strip detectors and has been installed in the BaBar experiment and taking colliding beam data since May 1999. An overview of the design as well as performance and experience from the initial running will be presented

  1. Refinement of crystal structures of CaHCl, SrHCl, BaHCl, BaHBr, and BaHI

    International Nuclear Information System (INIS)

    Beck, H.P.; Limmer, A.

    1983-01-01

    The structures of CaHCl, SrHCl, BaHBr, BaHCl, and BaHI have been refined using single crystal data. The comparison of the parameters with the corresponding data of isotypic fluorohalide compounds gives a valuable insight into the bonding interactions in this structure type. (author)

  2. Refinement of crystal structures of CaHCl, SrHCl, BaHCl, BaHBr, and BaHI

    Energy Technology Data Exchange (ETDEWEB)

    Beck, H.P.; Limmer, A. (Erlangen-Nuernberg Univ., Erlangen (Germany, F.R.). Inst. fuer Anorganische Chemie)

    1983-07-01

    The structures of CaHCl, SrHCl, BaHBr, BaHCl, and BaHI have been refined using single crystal data. The comparison of the parameters with the corresponding data of isotypic fluorohalide compounds gives a valuable insight into the bonding interactions in this structure type.

  3. Laserspectroscopic studies of collective properties of neutron deficient Ba nuclei

    International Nuclear Information System (INIS)

    Bekk, K.; Andl, A.; Goering, S.; Hanser, A.; Nowicki, G.; Rebel, H.; Schatz, G.

    1979-01-01

    Isotope shifts and hyperfine structure of the BaI resonance-line (lambda=553.6 nm) have been measured by dye laser induced resonance fluorescence on an atomic beam for sup(135m,129g,129m,126) Ba thus extending previous high resolution measurements of neutron deficient Ba nuclides (N - isomers sup(135m) Ba and sup(135m) Ba show a decreased staggering. Conspicuously the isomer shift of the g 7/2 + isomer sup(129m) Ba proves to be negative. The nuclear structure information is discussed in the context of gamma-spectroscopic studies of transitional nuclei with 50 [de

  4. Particle-hole states in 138Ba

    International Nuclear Information System (INIS)

    Bondarenko, V.A.; Khitrov, V.A.; Popov, Yu.P.; Brant, S.; Paar, V.; Simicic, L.

    1995-01-01

    The thermal-neutron-capture gamma rays and γγ-coincidences were measured by means of Ge detectors. Using primary and secondary (n, γ) data, the level scheme of 138 Ba was established with 63 levels up to an excitation energy of 5 MeV. The level energies and (d, p) transfer data were compared with model predictions of the interacting boson-fermion-fermion model. As shown, this model provides a basic understanding of the neutron particle-hole states of 138 Ba in the energy range of 3.5-5.0 MeV. ((orig.))

  5. PENGGUNAAN EKSTRAK DAUN SIRIH (Piper betle Linn UNTUK MENGHAMBAT BAKTERI Aeromonas hydrophila DAN TOKSISITASNYA PADA IKAN PATIN (Pangasius hypophthalmus (THE USE OF PIPER BETLE LINN EXTRACT ON AEROMONAS HYDROPHILA TO OBSTRUCT AND THE TOKSISITY TO PANGASIUS HYPOPHTHALMUS

    Directory of Open Access Journals (Sweden)

    Siti Aisiah

    2016-06-01

    Full Text Available Tujuan penelitian ini untuk mengetahui   daya  hambat  daun  sirih   yang  paling  besar  terhadap  bakteri Aeromonas Hydrophila, mengetahui konsentrasi minimal ekstrak daun sirih yang mampu menghambat pertumbuhan bakteri  A. hydrophila  dan mengetahui toksisitas konsentrasi efektif dari  ekstrak daun sirih terhadap ikan patin. Rancangan percobaan yang digunakan untuk  uji toksisitas  adalah rancangan acak lengkap, terdiri dari 4 perlakuan yaitu A  = Ikan disuntik dengan ekstrak daun sirih konsentrasi 75%, B  = Ikan disuntik dengan ekstrak daun sirih konsentrasi 25%, C  = Kontrol positif (ikan disuntik dengan akuades steril dan D  = Kontrol negatif (ikan tidak disuntik, diulang 3 kali. Hasil uji sensitivitas antibakteri daun sirih yang mempunyai daya hambat dan daya bunuh paling besar terhadap bakteri A. hydrophila adalah ekstrak daun sirih-metanol. Pengujian MIC menunjukkan bahwa ekstrak daun sirih-metanol memiliki daya hambat minimal 25 % terhadap aktivitas bakteri A. hydrophila. Hasil uji toksisitas yang dilakukan terhadap ikan patin dengan konsentrasi 75% dan 25% menunjukkan bahwa mortalitas yang terjadi tidak mencapai 50%. Pengamatan hematologis pada masing-masing perlakuan menunjukkan hasil yang berpengaruh tidak nyata terhadap kesehatan ikan patin. Parameter kualitas air pada penelitian ini yaitu, , kadar oksigen terlarut,  pH, amoniak, CO2 dan suhu masih dapat mendukung kehidupan ikan patin. This research was aimed a finding the part of Piper betle Linn  which had the biggest resistance to Aeromonas hydrophila bacteria and to know the minimal concentrate which could obstruct the growth of A. hydrophila  bacteria and to know effective concentrate toxicity of P. betle Linn  to Pangasius hypophthalmus.  The random sampling used proportionate stratified random sampling. In toxicity test, it had be done 4 treatment, which was given to fish, those were : A = fish was injected with 25 % concentrate of extract  P

  6. Subnitride chemistry: A first-principles study of the NaBa3N, Na5Ba3N, and Na16Ba6N phases

    International Nuclear Information System (INIS)

    Oliva, Josep M.

    2005-01-01

    An ab initio study on the electronic structure of the subnitrides NaBa 3 N, Na 5 Ba 3 N, and Na 16 Ba 6 N is performed for the first time. The NaBa 3 N and Na 5 Ba 3 N phases consist of infinite 1 ∞ [NBa 6/2 ] strands composed of face-sharing NBa 6 octahedra surrounded by a 'sea' of sodium atoms. The Na 16 Ba 6 N phase consist of discrete [NBa 6 ] octahedra arranged in a body-cubic fashion, surrounded by a 'sea' of sodium atoms. Our calculations suggest that the title subnitrides are metals. Analysis of the electronic structure shows partial interaction of N(2s) with Ba(5p) electrons in the lower energy region for NaBa 3 N and Na 5 Ba 3 N. However, no dispersion is observed for the N(2s) and Ba(5p) bands in the cubic phase Na 16 Ba 6 N. The metallic band below the Fermi level shows a strong mixing of N(2p), Ba(6s), Ba(5d), Ba(6p), Na(3s) and Na(3p) orbitals. The metallic character in these nitrides stems from delocalized electrons corresponding to hybridized 5d l 6s m 6p n barium orbitals which interact with hybridized 3s n 3p m sodium orbitals. Analysis of the electron density and electronic structure in these nitrides shows two different regions: a metallic matrix corresponding to the sodium atoms and the regions around them and heteropolar bonding between nitrogen and barium within the infinite 1 ∞ [NBa 6/2 ] strands of the NaBa 3 N and Na 5 Ba 3 N phases, and within the isolated [NBa 6 ] octahedra of the Na 16 Ba 6 N phase. The nitrogen atoms inside the strands and octahedra are negatively charged, the anionic character of nitrogens being larger in the isolated octahedra of the cubic phase Na 16 Ba 6 N, due to the lack of electron delocalization along one direction as opposed to the other phases. The sodium and barium atoms appear to be slightly negatively and positively charged, the latter to a larger extent. From the computed Ba-N overlap populations as well as the analysis of the contour maps of differences between total density and superposition of

  7. Is Urgent Evoke a Digital Ba?

    DEFF Research Database (Denmark)

    Wichmand, Mette

    2018-01-01

    of such a platform, the World Bank’s online game Urgent Evoke, which has been designed with the pur- pose of engaging citizens in developing innovative solutions for sociopolitical problems like poverty. The analysis is based on Nonaka’s concept of Ba, which means “place” and is described as a platform for advancing...

  8. The BaBar electromagnetic calorimeter

    CERN Document Server

    Lewandowski, B

    2002-01-01

    The BaBar electromagnetic calorimeter is a hermetic, total-absorption array of CsI(Tl)-crystals, operated at the asymmetric e sup - e sup + -collider PEP-II at SLAC. The design and the status of the performance as of February 2002 is presented.

  9. Electronic structure of Ca, Sr, and Ba under pressure.

    Science.gov (United States)

    Animalu, A. O. E.; Heine, V.; Vasvari, B.

    1967-01-01

    Electronic band structure calculations phase of Ca, Sr and Ba over wide range of atomic volumes under pressure electronic band structure calculations for fcc phase of Ca, Sr and Ba over wide range of atomic volumes under pressure electronic band structure calculations for fcc phase of Ca, Sr and Ba over wide range of atomic volumes under pressure

  10. Sekuensing 16S DNA Bakteri Selulolitik Asal Limbah Cairan Rumen Sapi Peranakan Ongole (SEQUENCING OF 16S DNA OF CELLULOLYTIC BACTERIA FROM BOVINE RUMEN FLUID WASTE ONGOLE CROSSBREED

    Directory of Open Access Journals (Sweden)

    Widya Paramita Lokapirnasari

    2017-04-01

    dilakukan identifikasi gen penyandi 16S DNA, amplifikasi DNA dengan polymerase chain reaction (PCR. Amplifikasi gen penyandi 16S DNA menggunakan Kit High Fidelity Platinum Taq DNA Polymerase dengan primer forward PB36 5’-AGR GTT TGA TCM TGG CTC AG-3’ dan primer reverse PB38 5’-GMT ACC TTG TTA CGA CTT-3’ yang digunakan untuk PCR. Hasil sekuensing nukleotida dari 16S DNA selanjutnya dibandingkan dengan urutan nukleotida dari GenBank database untuk dilakukan BLAST untuk mengidentifikasi berdasarkan pohon filogeni. Bakteri tersebut mampu menunjukkan adanya zona bening pada media Carboxymethyl cellulose (CMC dengan pewarnaan congo red. Adanya zona bening tersebut berhubungan dengan aktivitas mikrob untuk mendegradasi selulosa. Simpulan penelitian menunjukkan bahwa berdasarkan hasil urutan nukleotida genom 16S DNA serta pohon filogeni, maka isolat selulolitik tersebut diidentifikasi sebagai Enterobacter cloacae WPL 214.

  11. Dynamics of photoexcited Ba+ cations in 4He nanodroplets

    International Nuclear Information System (INIS)

    2UB, Universitat de Barcelona, Diagonal 645, 08028 Barcelona (Spain))" data-affiliation=" (Departament ECM, Facultat de Física, and IN2UB, Universitat de Barcelona, Diagonal 645, 08028 Barcelona (Spain))" >Leal, Antonio; 2UB, Universitat de Barcelona, Diagonal 645, 08028 Barcelona (Spain))" data-affiliation=" (Departament ECM, Facultat de Física, and IN2UB, Universitat de Barcelona, Diagonal 645, 08028 Barcelona (Spain))" >Pi, Martí; Zhang, Xiaohang; Drabbels, Marcel; 2UB, Universitat de Barcelona, Diagonal 645, 08028 Barcelona (Spain); Laboratoire des Collisions, Agrégats, Réactivité, IRSAMC, UMR 5589, CNRS et Université Paul Sabatier-Toulouse 3, 118 route de Narbonne, F-31062 Toulouse Cedex 09 (France))" data-affiliation=" (Departament ECM, Facultat de Física, and IN2UB, Universitat de Barcelona, Diagonal 645, 08028 Barcelona (Spain); Laboratoire des Collisions, Agrégats, Réactivité, IRSAMC, UMR 5589, CNRS et Université Paul Sabatier-Toulouse 3, 118 route de Narbonne, F-31062 Toulouse Cedex 09 (France))" >Barranco, Manuel; Cargnoni, Fausto; Hernando, Alberto; Mateo, David; Mella, Massimo

    2016-01-01

    We present a joint experimental and theoretical study on the desolvation of Ba + cations in 4 He nanodroplets excited via the 6p ← 6s transition. The experiments reveal an efficient desolvation process yielding mainly bare Ba + cations and Ba + He n exciplexes with n = 1 and 2. The speed distributions of the ions are well described by Maxwell-Boltzmann distributions with temperatures ranging from 60 to 178 K depending on the excitation frequency and Ba + He n exciplex size. These results have been analyzed by calculations based on a time-dependent density functional description for the helium droplet combined with classical dynamics for the Ba + . In agreement with experiment, the calculations reveal the dynamical formation of exciplexes following excitation of the Ba + cation. In contrast to experimental observation, the calculations do not reveal desolvation of excited Ba + cations or exciplexes, even when relaxation pathways to lower lying states are included.

  12. Baština Starog grada Zrinskih

    OpenAIRE

    Kovač, Ivana

    2017-01-01

    Stari grad Zrinskih priča bogate, zanimljive i velike priče u svakom svojem kutku. Dvorac je prepun kulturne baštine koja će svakog ostaviti bez daha i dat će nam nove poglede na hrvatsku povijest, a još više na međimursku povijest. U ovom završnom radu pisat ću o ljepotama kraja, povijesnim zbivanjima i kulturnoj baštini grada, od samog početka pa do danas. Posebno ću se posvetiti predmetima koji su nam ostavili naši preci, a najviše umjetnosti grada i okolice. Čakovečki stari grad ima djelo...

  13. Topological phases in Ba-Borate glasses

    Science.gov (United States)

    Holbrook, Chad; Czaja, Andrew; Boolchand, Punit

    2015-03-01

    Twelve compositions in the (BaO)x(B2O3)100-x pseudo binary, in the 15% Modulated- DSC and Raman scattering experiments were undertaken systematically as function of BaO content (x). Calorimetric measurements reveal Tg(x) to show a broad maximum and the non-reversing enthalpy to show a Gaussian-like reversibility window2, both centered near x = 28%. Raman scattering displays rich lineshapes with modes similar to those observed in Na-Borates2. Modes near 808 cm-1, 770 cm-1, 740 cm-1 and 705 cm-1 are observed, and identified with breathing modes of pure and mixed rings from characteristic structural groupings2. These preliminary results suggest that glasses at x 30% in the flexible phase. Supported by NSF Grant DMR 08-53957.

  14. Formulasi Bakteri Endofit Akar Kedelai untuk Pengendalian Pustul Bakteri

    Directory of Open Access Journals (Sweden)

    Trimurti Habazar

    2015-04-01

    Full Text Available Two isolates of bacterial endophyte from soybean root were found to be effective to control bacterial pustule caused by Xanthomonas axonopodis pv. glycines. Formulation of the bacterial isolates is required to maintain the effectivity of this bacterial isolates during storage, transportation and application. The aim of this research was to obtain the best carrier for formulation to maintain the effectivity of bacterial endophyte in storage to control bacterial pustule on soybean. Three kind of carrier agent was evaluated for formulation of bacterial endophyte i.e. peat soil, tapioca flour and coconut water + 1% palm oil. Each carrier agent was combined with 5 treatment of storage time i.e. 0, 1, 3, 5 and 7 weeks. Soybean plants was inoculated by. X. axonopodis pv. glycines 2 weeks after planting by rubbing bacterial suspension (106 cel mL-1 on lower surface of leaves. The results showed that all formulas of bacterial endophyte were able to suppress the bacterial pustule on soybean. The best formulations were bacterial endophyte in peat soil stored for 1 and 7 weeks (effectivity rate 79.85% and 77.02% and coconut water + palm oil and storaged for 3 weeks (effectivity rate 77.46%.

  15. Chemical correlations in Caetite (BA) region, Brazil

    International Nuclear Information System (INIS)

    Gennari, R.F.; Almeida, Geangela M.; Souza, S.O.

    2013-01-01

    Brazil's economic situation is responsible for an urgent demand for energy. There are several ways to generate energy, in some localities of our country, energy generation occurs almost exclusively by nuclear route, as in Rio de Janeiro state. Brazil has the sixth largest reserve of the uranium ore in the world. Nowadays there is only one mine under exploration (Uraniferous District of Lagoa Real - Caetite-BA). Unfortunately, nuclear power generation is better known, by common citizen, more for its unwanted effects than for its benefits. This fact is also powered by some Non-Governmental Organizations (NGOs), such as Greenpeace, who claim the uranium mine is dangerous since it causes environmental contamination. However, Industrias Nucleares do Brasil (INB) rejected these accusations. In a previous study, we demonstrated that doses of the Caetite (BA) population are consistent with those usually found in other countries. We stated also the higher concentration of 238 U determined, in only one water sample, is probably due to natural processes, as soil leaching. In order to verify the existing natural processes, macro and micro chemical elements present in water and soil samples collected in the Caetite (BA) region were determined by ICP-MS. The results were transformed into dendrograms where chemical correlations are evidenced and they are consistent with existing natural chemical processes. It was also possible to observe a correlation between samples corroborating with the Geographic Information Systems data to be presented in this same scientific event. (author)

  16. Chemical correlations in Caetite (BA) region, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Gennari, R.F., E-mail: rgennari@usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Inst. de Fisica. Dept. de Fisica Nuclear; Campos, S.S., E-mail: simaracampos@gmail.com [Universidade Estadual do Sudoeste da Bahia (UESB), Itapetinga, BA, (Brazil); Almeida, Geangela M.; Souza, S.O., E-mail: susanasouzalalic@gmail.com [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Dept. de Fisica

    2013-07-01

    Brazil's economic situation is responsible for an urgent demand for energy. There are several ways to generate energy, in some localities of our country, energy generation occurs almost exclusively by nuclear route, as in Rio de Janeiro state. Brazil has the sixth largest reserve of the uranium ore in the world. Nowadays there is only one mine under exploration (Uraniferous District of Lagoa Real - Caetite-BA). Unfortunately, nuclear power generation is better known, by common citizen, more for its unwanted effects than for its benefits. This fact is also powered by some Non-Governmental Organizations (NGOs), such as Greenpeace, who claim the uranium mine is dangerous since it causes environmental contamination. However, Industrias Nucleares do Brasil (INB) rejected these accusations. In a previous study, we demonstrated that doses of the Caetite (BA) population are consistent with those usually found in other countries. We stated also the higher concentration of {sup 238}U determined, in only one water sample, is probably due to natural processes, as soil leaching. In order to verify the existing natural processes, macro and micro chemical elements present in water and soil samples collected in the Caetite (BA) region were determined by ICP-MS. The results were transformed into dendrograms where chemical correlations are evidenced and they are consistent with existing natural chemical processes. It was also possible to observe a correlation between samples corroborating with the Geographic Information Systems data to be presented in this same scientific event. (author)

  17. The BaBar Data Acquisition System

    CERN Document Server

    Scott, I; Grosso, P; Huffer, M E; O'Grady, C; Russell, J J

    1999-01-01

    The BaBar experiment at the Stanford Linear Accelerator Center is designed to perform a search for CP violation by ana-lyzing the decays of a very large sample of B and B(Bar) mesons produced at the high luminosity PEP-II accelerator. The data acquisition system must cope with a sustained high event rate, while supporting real time feature extraction and data compression with minimal dead time. The BaBar data acquisition system is based around a common VME interface to the electronics read-out of the separate detec-tor subsystems. Data from the front end electronics is read into commercial VME processors via a custom "Personality Card" and PCI interface. The commercial CPUs run the Tornado operating system to provide a platform for detector subsystem code to perform the necessary data processing. The data is read out via a non-blocking network switch to a farm of commercial UNIX processors. The current implementation of the BaBar data acquisition sys-tem has been shown to sustain a Level 1 trigger rate of 1.3...

  18. Improvement of the field-trapping capabilities of bulk Nd Ba Cu O superconductors using Ba Cu O substrates

    Science.gov (United States)

    Matsui, Motohide; Nariki, Shinya; Sakai, Naomichi; Iwafuchi, Kengo; Murakami, Masato

    2006-07-01

    We used Ba-Cu-O substrates to fabricate bulk Nd-Ba-Cu-O superconductors using a top-seeded melt-growth method. There were several advantages for the use of Ba-Cu-O substrate compared to conventional substrate materials such as MgO, ZrO2, Al2O3, RE123 and RE211 (RE = rare earth). The Ba-Cu-O did not react with the precursor and minimized liquid loss. Accordingly, the introduction of large-sized cracks was suppressed. We also found that Tc values were high at the bottom regions, which was ascribed to the beneficial effect of Ba-Cu-O in suppressing Nd/Ba substitution. As a result, we obtained bulk Nd-Ba-Cu-O superconductors that exhibited fairly good field-trapping capabilities, even at the bottom surfaces.

  19. Mikrobiologer ser bakterier i kortene

    DEFF Research Database (Denmark)

    Harmsen, Morten; Sternberg, Claus; Haagensen, Janus Anders Juul

    2008-01-01

    at klumpe sig sammen i slimede biofilm, som især er et stort problem på hospitalerne og hos patienter med kroniske infektioner. For at kunne bekæmpe biofi lm må forskerne vide mere om, hvorfor og hvordan filmen dannes. Ny viden inden for mikrobiologien og udviklingen af nanoteknologiske mikroskoper hjælper...

  20. Bıldırcın ve Ördek Yumurtalarında Maya-Küf ve Total Bakteri Açısından İncelenmesi

    Directory of Open Access Journals (Sweden)

    Işın Var

    2015-02-01

    Full Text Available Bıldırcın yumurtası, besin değeri yönünden tavuk yumurtasından oransal olarak daha zengin kabul edilmektedir. Daha çok salata, pasta, mayonez vb. yapımında yaygın olarak kullanılan ördek yumurtası (Pekin ördeği tavuk yumurtasına göre daha büyük olup, ağırlıkları 70-90 g arasında değişmektedir. Bıldırcın yumurtası son yıllarda özellikle küçük çocuk ve yaşlı beslenmesinde önem kazanmıştır. Bunun yanısıra bazı hastalıkların tedavisi amacıyla da halk arasında oldukça yaygın kullanılmaktadır. Özellikle çiğ olarak tüketilen bıldırcın yumurtaları zaman zaman içerdikleri patojen mikroorganizmalarla tehlikeli olabilmektedirler. Bu çalışmada bıldırcın ve ördek yumurtalarında maya-küf ve total bakteri aranmıştır. Bıldırcın ve ördek yumurtalarının özellikle kabuğunda hem total bakteri hem de maya-küf bulunmuştur. Bıldırcın yumurtasının akı ve sarısında ise zaman zaman kontaminasyonla karşılaşılmıştır.

  1. High spin structure in 130,131Ba

    International Nuclear Information System (INIS)

    Kaur, Navneet; Kumar, A.; Singh, Amandeep; Kumar, S.; Kaur, Rajbir; Singh, Varinderjit; Behera, B.R.; Singh, K.P.; Singh, G.; Mukherjee, G.; Sharma, H.P.; Kumar, Suresh; Kumar Raju, M.; Madhusudhan Rao, P.V.; Muralithar, S.; Singh, R.P.; Kumar, Rakesh; Madhvan, N.; Bhowmik, R.K.

    2014-01-01

    High spin states of 130,131 Ba have been investigated via fusion evaporation reactions 122 Sn( 13 C,4n) 131 Ba and 122 Sn( 13 C, 5n) 130 Ba at E beam =65 MeV. The level schemes of 130,131 Ba have been extended by placing several new γ transitions. A few interband transitions connecting two negative-parity bands, which are the experimental fingerprints of signature partners, have been established in 130 Ba. Spin and parity of a side band have been assigned in 131 Ba and this dipole band is proposed to have a three-quasiparticle configuration, νh 11/2 x πh 11/2 x πg 7/2 . The observed band structures and nuclear shape evolution as a function of the angular momentum have been discussed in the light of Total-Routhian-Surface calculations. (orig.)

  2. Hadronic Physics Studies at BaBar

    International Nuclear Information System (INIS)

    Stroili, R.

    2006-01-01

    A new resonance Y(4260) with a mass of 4259 ± 8 -6 +2 MeV/c 2 and J PC = 1 -- , discovered by the BaBar experiment shows peculiar behavior in his decay mode. The Λ c + baryon mass has been measured, using its decays to ΛK S 0 K + and Σ 0 K S 0 K + , and its value is 2286.46 ± 0.14 MeV/c 2 , the precision is greatly improved w.r.t. PDG value. Ξ c 0 and (Omega) c 0 decays and production have been studied with results greatly improved w.r.t. PDG

  3. Revisiting the BaO2/BaO redox cycle for solar thermochemical energy storage.

    Science.gov (United States)

    Carrillo, A J; Sastre, D; Serrano, D P; Pizarro, P; Coronado, J M

    2016-03-21

    The barium peroxide-based redox cycle was proposed in the late 1970s as a thermochemical energy storage system. Since then, very little attention has been paid to such redox couples. In this paper, we have revisited the use of reduction-oxidation reactions of the BaO2/BaO system for thermochemical heat storage at high temperatures. Using thermogravimetric analysis, reduction and oxidation reactions were studied in order to find the main limitations associated with each process. Furthermore, the system was evaluated through several charge-discharge stages in order to analyse its possible degradation after repeated cycling. Through differential scanning calorimetry the heat stored and released were also determined. Oxidation reaction, which was found to be slower than reduction, was studied in more detail using isothermal tests. It was observed that the rate-controlling step of BaO oxidation follows zero-order kinetics, although at high temperatures a deviation from Arrhenius behaviour was observed probably due to hindrances to anionic oxygen diffusion caused by the formation of an external layer of BaO2. This redox couple was able to withstand several redox cycles without deactivation, showing reaction conversions close to 100% provided that impurities are previously eliminated through thermal pre-treatment, demonstrating the feasibility of this system for solar thermochemical heat storage.

  4. Strain induced optical properties of BaReO3

    Science.gov (United States)

    Kumavat, Sandip R.; Kansara, Shivam; Gupta, Sanjeev K.; Sonvane, Yogesh

    2018-05-01

    Here, we have performed strain induce optical properties of BaReO3 by using density functional theory (DFT). We noticed that after applying intrinsic and extrinsic strain to the BaReO3, it shows the metallic behavior. We also studied optical properties, which show good activity in the ultraviolet region. The results show that after applying intrinsic and extrinsic strain to BaReO3 the absorption peaks are shifted towards the high UV region of the spectrum. Thus, we concluded that, BaReO3 material with extrinsic strain can be useful for high frequency UV device and optoelectronic devices.

  5. Incorporation of Ba in Al and Fe pollucite

    Energy Technology Data Exchange (ETDEWEB)

    Vance, Eric R., E-mail: erv@ansto.gov.au [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001 Kirrawee DC, NSW 2232 (Australia); Gregg, Daniel J.; Griffiths, Grant J. [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001 Kirrawee DC, NSW 2232 (Australia); Gaugliardo, Paul R. [Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Crawley, WA 6009 (Australia); Grant, Charmaine [Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Locked Bag 2001 Kirrawee DC, NSW 2232 (Australia)

    2016-09-15

    Ba, the transmutation product of radioactive Cs, can be incorporated at levels of up to ∼0.07 formula units in Cs{sub (1−2x)}Ba{sub x}AlSi{sub 2}O{sub 6} aluminium pollucite formed by sol-gel methods and sintering at 1400 °C, with more Ba forming BaAl{sub 2}Si{sub 2}O{sub 8} phases. The effect of Ba substitution in pollucite-structured CsFeSi{sub 2}O{sub 6} was also studied and no evidence of Ba substitution in the pollucite structure via cation vacancies or Fe{sup 2+} formation was obtained. The Ba entered a Fe-silicate glass structure. Charge compensation was also attempted with a Cs{sup +} + Fe{sup 3+} ↔ Ba{sup 2+} + Ni{sup 2+} scheme but again the Ba formed a glass and NiO was evident. PCT leaching data showed CsFeSi{sub 2}O{sub 6} to be very leach resistant. - Highlights: • Barium can be incorporated into aluminium pollucite. • Positron annihilation lifetime spectroscopy supports a charge vacancy mechanism of incorporation. • Iron pollucite does not appear to incorporate any barium with either vacancy or charge compensation mechanisms. • Leaching data suggest iron pollucite is very leach resistant.

  6. Syntheses and crystal structures of BaAgTbS{sub 3}, BaCuGdTe{sub 3}, BaCuTbTe{sub 3}, BaAgTbTe{sub 3}, and CsAgUTe{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Prakash, Jai; Beard, Jessica C.; Ibers, James A. [Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3113 (United States); Mesbah, Adel [Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3113 (United States); ICSM-UMR 5257 CNRS/CEA/UM2/ENSCM, Bat 426, BP 17171, 30207 Bagnols/Ceze (France)

    2015-06-15

    Five new quaternary chalcogenides of the 1113 family, namely BaAgTbS{sub 3}, BaCuGdTe{sub 3}, BaCuTbTe{sub 3}, BaAgTbTe{sub 3}, and CsAgUTe{sub 3}, were synthesized by the reactions of the elements at 1173-1273 K. For CsAgUTe{sub 3} CsCl flux was used. Their crystal structures were determined by single-crystal X-ray diffraction studies. The sulfide BaAgTbS{sub 3} crystallizes in the BaAgErS{sub 3} structure type in the monoclinic space group C{sup 3},{sub 2h}-C2/m, whereas the tellurides BaCuGdTe{sub 3}, BaCuTbTe{sub 3}, BaAgTbTe{sub 3}, and CsAgUTe{sub 3} crystallize in the KCuZrS{sub 3} structure type in the orthorhombic space group D{sup 1},{sub 2}{sup 7},{sub h}-Cmcm. The BaAgTbS{sub 3} structure consists of edge-sharing [TbS{sub 6}{sup 9-}] octahedra and [AgS{sub 5}{sup 9-}] trigonal pyramids. The connectivity of these polyhedra creates channels that are occupied by Ba atoms. The telluride structure features {sup 2}{sub ∞}[MLnTe{sub 3}{sup 2-}] layers for BaCuGdTe{sub 3}, BaCuTbTe{sub 3}, BaAgTbTe{sub 3}, and {sup 2}{sub ∞}[AgUTe{sub 3}{sup 1-}] layers for CsAgUTe{sub 3}. These layers comprise [MTe{sub 4}] tetrahedra and [LnTe{sub 6}] or [UTe{sub 6}] octahedra. Ba or Cs atoms separate these layers. As there are no short Q..Q (Q = S or Te) interactions these compounds achieve charge balance as Ba{sup 2+}M{sup +}Ln{sup 3+}(Q{sup 2-}){sub 3} (Q = S and Te) and Cs{sup +}Ag{sup +}U{sup 4+}(Te{sup 2-}){sub 3}. (Copyright copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Chemiluminescence from the reaction of Ba 3D with nitric oxide

    International Nuclear Information System (INIS)

    Johnson, S.A.; Solarz, R.W.; Dubrin, J.W.; Brotzmann, R.

    1977-01-01

    The reaction of laser excited Ba*( 3 D) states with nitric oxide is presented. BaO product is not detected, although the channel is thermodynamically open, and instead chemiluminescence is observed. Experiments which suggest that radiative recombination, Ba + NO → BaNO* → BaNO, is the observed reaction channel will also be presented

  8. Isolation of Lactic Acid Bacteria That Produce Protease and Bacteriocin-Like Substance From Mud Crab (Scylla sp. Digestive Tract (Isolasi Bakteri Asam Laktat yang Menghasilkan Protease dan Senyawa Bacteriocin-Like dari Saluran Pencernaan Kepiting

    Directory of Open Access Journals (Sweden)

    Heru Pramono

    2015-03-01

    Kata kunci: Bakteri Asam Laktat, Bakteriosin-like substance, Protease, Scylla  sp. Digestive tract is complex environment consist of large amount of bacteria’s species. Fish intestine bacteria consist of aerobic or facultative anaerob bacteria which can produce antibacterial and enzym. The objectives of this research were to isolated lactic acid bacteria that produce bacteriocin-like and protease from mud crab digestive tract. Isolation and characterization of isolates were conducted employing media MRS.  Neutralized cell free supernatant of isolates were tested using disc diffusion agar of against pathogenic and spoilage bacteria to indicate bacteriocin-like-producing lactic acid bacteria. Protease-producing isolate was tested using disc diffusion method in casein agar. Among a hundred isolates, 96 isolates were showed clear zone in MRS+CaCO3,, catalase negative, and Gram positive bacteria. Thirty four isolates produced protease and only four isolates (i.e. IKP29, IKP30, IKP52, and IKP94 showed strong inhibition against pathogenic and spoilage bacteria. There were three patterns of inhibition among three isolates against Bacillus subtilis, Staphylococcus aureus, Eschericia coli, and Salmonella sp. All three isolates showed potential uses for produce starter culture for fishery product fermentation purpose. This is the first report of isolation lactic acid bacteria that produced protease and bacteriocin-like from digestive tract of mud crab. Keywords: Lactic acid bacteria, Bacteriocin-like substance, Protease, Scylla  sp.

  9. Co2FeAl based magnetic tunnel junctions with BaO and MgO/BaO barriers

    Directory of Open Access Journals (Sweden)

    J. Rogge

    2015-07-01

    Full Text Available We succeed to integrate BaO as a tunneling barrier into Co2FeAl based magnetic tunnel junctions (MTJs. By means of Auger electron spectroscopy it could be proven that the applied annealing temperatures during BaO deposition and afterwards do not cause any diffusion of Ba neither into the lower Heusler compound lead nor into the upper Fe counter electrode. Nevertheless, a negative tunnel magnetoresistance (TMR ratio of -10% is found for Co2FeAl (24 nm / BaO (5 nm / Fe (7 nm MTJs, which can be attributed to the preparation procedure and can be explained by the formation of Co- and Fe-oxides at the interfaces between the Heusler and the crystalline BaO barrier by comparing with theory. Although an amorphous structure of the BaO barrier seems to be confirmed by high-resolution transmission electron microscopy (TEM, it cannot entirely be ruled out that this is an artifact of TEM sample preparation due to the sensitivity of BaO to moisture. By replacing the BaO tunneling barrier with an MgO/BaO double layer barrier, the electric stability could effectively be increased by a factor of five. The resulting TMR effect is found to be about +20% at room temperature, although a fully antiparallel state has not been realized.

  10. Hyperfine structure and isotope shift of the neutron-rich barium isotopes 139-146Ba and 148Ba

    International Nuclear Information System (INIS)

    Wendt, K.; Ahmad, S.A.; Klempt, W.; Neugart, R.; Otten, E.W.

    1988-01-01

    The hyperfine structure and isotope shift in the 6s 2 S 1/2 -6p 2 P 3/2 line of Ba II (455.4 nm) have been measured by collinear fast-beam laser spectroscopy for the neutron-rich isotopes 139-146 Ba and 148 Ba. Nuclear moments and mean square charge radii of these isotopes have been recalculated. The isotope shift of the isotope 148 Ba (T 1/2 = 0.64 s) could be studied for the first time, yielding δ 2 > 138,148 = 1.245(3) fm 2 . (orig.)

  11. Effect of local environment on crossluminescence kinetics in SrF{sub 2}:Ba and CaF{sub 2}:Ba solid solutions

    Energy Technology Data Exchange (ETDEWEB)

    Terekhin, M.A. [P.N. Lebedev Physical Institute, Leninskij Prospekt 53, 119991 Moscow (Russian Federation); Makhov, V.N., E-mail: makhov@sci.lebedev.ru [P.N. Lebedev Physical Institute, Leninskij Prospekt 53, 119991 Moscow (Russian Federation); Lebedev, A.I.; Sluchinskaya, I.A. [Lomonosov Moscow State University, Moscow 119991 (Russian Federation)

    2015-10-15

    Spectral and kinetic properties of extrinsic crossluminescence (CL) in SrF{sub 2}:Ba (1%) and CaF{sub 2}:Ba (1%) are compared with those of intrinsic CL in BaF{sub 2} and are analyzed taking into account EXAFS data obtained at the Ba L{sub III} edge and results of first-principles calculations. The CL decay time was revealed to be longer in SrF{sub 2}:Ba and CaF{sub 2}:Ba compared to BaF{sub 2}. This fact contradicts the expected acceleration of luminescence decay which could result from an increased overlap of wave functions in solid solutions due to shortening of the Ba-F distance obtained in both EXAFS measurements and first-principles calculations. This discrepancy is explained by the effect of migration and subsequent non-radiative decay of the Ba (5p) core holes in BaF{sub 2} and by decreasing of the probability of optical transitions between Ba (5p) states and the valence band in SrF{sub 2}:Ba and CaF{sub 2}:Ba predicted by first-principles calculations. - Highlights: • The crossluminescence kinetics in SrF{sub 2}:Ba and CaF{sub 2}:Ba is slower than in BaF{sub 2}. • Ba{sup 2+} ions substitute for host Ca{sup 2+}(Sr{sup 2+}) ions in the on-center positions. • The nearest Ba-F distances in SrF{sub 2}:Ba and CaF{sub 2}:Ba are shorter than in BaF{sub 2}. • EXAFS data and first-principles calculations of the local structure agree well. • First-principles calculations explain slower luminescence decay in solid solutions.

  12. A Dubious Distinction? The BA versus the BS in Psychology

    Science.gov (United States)

    Pfund, Rory A.; Norcross, John C.; Hailstorks, Robin; Aiken, Leona S.; Stamm, Karen E.; Christidis, Peggy

    2016-01-01

    Previous studies have documented small differences between the bachelor of arts (BA) and the bachelor of science (BS) psychology degrees in their general education core requirements, particularly mathematics and science courses. But are there differences between the BA and BS degrees within the psychology curriculum? Using data from the…

  13. Intertextuality in Ba's So Long a Letter and Umunnakwe's Dear ...

    African Journals Online (AJOL)

    Intertextuality takes for granted the interdependence of literary texts because every artistic creation is a re-echoing of past knowledge. Mariama Ba's So Long A Letter and Ndubisi Umunnakwe's Dear Ramatoulaye are African examples. This work examines how Ba's So Long A Letter intertextualises with Umunnakwe's Dear ...

  14. Proton microbeam irradiation effects on PtBA polymer

    Indian Academy of Sciences (India)

    Microbeam irradiation effects on poly-tert-butyl-acrylate (PtBA) polymer using 2.0 MeV proton microbeam are reported. Preliminary results on pattern formation on PtBA are carried out as a function of fluence. After writing the pattern, a thin layer of Ge is deposited. Distribution of Ge in pristine and ion beam patterned surface ...

  15. Crystal structure of a new natural (Ba, Nb) silicate

    International Nuclear Information System (INIS)

    Yamnova, N.A.; Pushcharovskii, D.Yu.; Voloshin, A.V.

    1990-01-01

    The structure of a new mineral Ba 3 (Ti 1.2 Nb 4.8 ) Si 4 O 25.4 is determined (166 reflections, method of least squares in anisotropic approximation, R = 0.040). The crystallographic parameters are: a = 9.03(1), c = 7.868(6) angstrom, Z = 1, space group P anti 62m. Like the previously investigated synthetic analogs Ba 3 Si 4 Nb 6 O 26 , Ba 3 Si 4 Ti 6 O 23 , and Ba 3 Si 4 Ta 6 O 26 , the structure contains a mixed framework of octahedral columns of triangular section, bound to the diortho groups [Si 2 O 7 ], of which the cavities contain the Ba atoms

  16. Thermoelectric properties of doped BaHfO_3

    International Nuclear Information System (INIS)

    Dixit, Chandra Kr.; Bhamu, K. C.; Sharma, Ramesh

    2016-01-01

    We have studied the structural stability, electronic structure, optical properties and thermoelectric properties of doped BaHfO_3 by full potential linearized augmented plane wave (FP-LAPW) method. The electronic structure of BaHfO_3 doped with Sr shows enhances the indirect band gaps of 3.53 eV, 3.58 eV. The charge density plots show strong ionic bonding in Ba-Hf, and ionic and covalent bonding between Hf and O. Calculations of the optical spectra, viz., the dielectric function, refractive index and extinction coefficient are performed for the energy range are calculated and analyzed. Thermoelectric properties of semi conducting are also reported first time. The doped BaHfO_3 is approximately wide band gap semiconductor with the large p-type Seebeck coefficient. The power factor of BaHfO_3 is increased with Sr doping, decreases because of low electrical resistivity and thermal conductivity.

  17. Flora da Paraíba, Brasil: Loganiaceae Flora of Paraíba, Brazil: Loganiaceae

    Directory of Open Access Journals (Sweden)

    Kiriaki Nurit

    2005-06-01

    Full Text Available Neste trabalho apresenta-se o tratamento taxonômico da família Loganiaceae, como parte do projeto "Flora da Paraíba", que vem sendo realizado com o objetivo de identificar e catalogar as espécies da flora local. Realizouse coletas e observações de campo para as identificações, descrições e ilustrações botânicas que foram efetuadas após estudos morfológicos, com o auxílio da bibliografia especializada, complementados pela análise de fotos de tipos, espécimes dos herbários EAN, JPB e IPA, e comparação com material identificado por especialistas. Registrou-se para a Paraíba quatro espécies: Spigelia anthelmia L., com ampla distribuição, e três espécies de Strychnos, somente coletadas em remanescentes de Mata Atlântica, S. atlantica Krukoff & Barneby, S. parvifolia A. DC. e S. trinervis (Vell. Mart.This work constitutes a taxonomic treatment of the Loganiaceae family as part of the project "Flora da Paraíba", which have been carried out with the objective to identify and catalogue the species of the local flora. The botanical identifications and illustrations were made by morphological studies supported by bibliography, analysis of the types, specimens from herbaria EAN, JPB and IPA, and comparison with samples previously identified by specialists, complemented by field observations. Four species of Loganiaceae belonging two genera were found in State of Paraíba: Spigelia anthelmia L. that has wide distribution and three species of Strychnos, found on remains of Atlantic forest, which are S. atlantica Krukoff & Barneby, S. parvifolia A. DC. and S. trinervis (Vell. Mart.

  18. Chalcogenidosilicates: Ba/sub 2/SiTe/sub 4/ and Ba/sub 2/SiSe/sub 4/

    Energy Technology Data Exchange (ETDEWEB)

    Brinkmann, C; Eisenmann, B; Schaefer, H [Technische Hochschule Darmstadt (Germany, F.R.). Fachbereich Anorganische Chemie und Kernchemie

    1985-05-01

    The new compounds Ba/sub 2/SiSe/sub 4/ and Ba/sub 2/SiTe/sub 4/ crystallize in the monoclinic system, space group: P2/sub 1//m (No. 11) with the lattice constants Ba/sub 2/SiSe/sub 4/: a = 918.4(5) pm, b = 703.3(3) pm, c = 687.2(3) pm, ..beta.. = 109.2(1)/sup 0/, Ba/sub 2/SiTe/sub 4/: a = 965.0(5) pm, b = 762.6(3) pm, c = 746.6(3) pm, ..beta.. = 108.9(1)/sup 0/. Both compounds are isotypic to the Sr/sub 2/GeS/sub 4/ structure. Ba/sub 2/SiTe/sub 4/ is the first o-telluridosilicate with discrete SiTe/sub 4//sup 4 -/ anions.

  19. Nuclear spectroscopy of doubly-even130,132Ba

    Science.gov (United States)

    Gupta, Anuradha; Gupta, Surbhi; Singh, Suram; Bharti, Arun

    2018-05-01

    A comparative study of some high-spin characteristic nuclear structure properties of doubly-even 130,132Ba nuclei has been made using two microscopic frameworks - CHFB and PSM. The yrast spectra, intrinsic quadrupole moment and deformation systematics of these nuclei have been successfully calculated. Further, the calculated data from both the frameworks is also compared with the available experimental data and a good agreement has been obtained. The present CHFB calculations describes very well the low spin structure of even-even 130,132Ba nuclei whereas PSM calculations provide a qualitative description of the high-spin band structure of doubly-even 130,132Ba nuclei.

  20. Processing of R-Ba-Cu-O superconductors

    International Nuclear Information System (INIS)

    Wu, H.

    1998-01-01

    Precipitation processes were developed to introduce second phases as flux pinning centers in Gd-Ba-Cu-O and Nd-Ba-Cu-O superconductors. In Gd-Ba-Cu-O, precipitation is caused by the decrease of the upper solubility limit of Gd 1+x Ba 2-x Cu 3 O 7 solid solution (Gd123ss) in low oxygen partial pressure. Processing of supersaturated Gd 1.2 Ba 1.8 Cu 3 O 7 in low oxygen partial pressure can produce dispersed second phases. Gd211 is formed as a separate phase while extensive Gd124 type stacking fault is formed instead of a separate CuO phase. As a result of the precipitation reaction, the transition temperature and critical current density are increased. In Nd-Ba-Cu-O, precipitation is caused by the decrease of the lower solubility limit of Nd 1+x Ba 2-x Cu 3 O 7 solid solution (Nd123ss) in oxygen. DTA results reveal the relative stability of Nd123ss in different oxygen partial pressures. In 1 bar oxygen partial pressure, Nd123ss with x = 0.1 is the most stable phase. In lower oxygen partial pressures, the most stable composition shifts towards the stoichiometric composition. The relative stability changes faster with decreasing oxygen partial pressure. Therefore, processing in oxygen and air tends to produce broad superconducting transitions but sharp transitions can be achieved in 0.01 bar and 0.001 bar oxygen partial pressures. While the lower solubility limits in 0.01 bar and 0.001 bar oxygen partial pressures remain at x = 0.00, the solubility limits in oxygen and air show a narrowing with decreasing temperature. Because of the narrowing of the solubility range in oxygen, oxygen annealing of Nd123 initially processed in low oxygen partial pressures will result in precipitation of second phases. The equilibrium second phase is BaCuO 2 for temperature above 608 C, and at lower temperatures the equilibrium second phases are Ba 2 CuO 3.3 and Ba 2 Cu 3 O 5+y . However, annealing at low temperature may produce a fine metastable transition phase. A coherent intermediate

  1. EFEKTIVITAS KAPORIT PADA PROSES KLORINASI TERHADAP PENURUNAN BAKTERI Coliform DARI LIMBAH CAIR RUMAH SAKIT X SAMARINDA (The Effectiveness of Calcium Hypochlorite to Chlorination Process in Decreasing the Amount of Coliform Bacteria in the Wastewater of X

    Directory of Open Access Journals (Sweden)

    Muhammad Busyairi

    2016-07-01

    Full Text Available ABSTRAK Kaporit pada limbah cair rumah sakit digunakan sebagai desinfektan, tetapi, penggunaan kaporit dengan dosis yang tidak tepat akan menyebabkan pembentukan senyawa Trihalomethane (THMs yang beracun dan bersifat karsinogenik. Pada limbah cair rumah sakit X Samarinda, diperoleh nilai MPN Coliform sebesar >160.000 MPN / 100 mL dengan residu klor sebesar 0 ppm. Penelitian ini bertujuan untuk menentukan dosis optimum dari penggunaan kaporit menggunakan titik Breakpoint Chlorination (BPC dan pengaruhnya terhadap penurunan Coliform. Analisis dilakukan dengan titrasi iodometri dan menghitung jumlah bakteri Coliform memakai metode Most Probable Number (MPN. Penentuan dosis kaporit berdasarkan dosis optimum pada titik BPC dimaksudkan agar dapat menjaga residu klor dari penambahan dosis yang semakin meningkat. Hasil penelitian mempengarui rerata kadar bahan organik pada sampel limbah cair sebesar 137,26 ppm, sehingga dosis kaporit yang dibubuhkan dimulai dari 130-165 ppm. Titik BPC terjadi pada pembubuhan klor aktif 160 ppm untuk kedua waktu kontak yaitu 30 dan 40 menit. Pada titik BPC, waktu kontak 30 menit diperoleh rerata persentase penurunan nilai Coliform yaitu 98,21% sebesar 2.899 MPN / 100 mL dengan residu klor sebesar 88 ppm. Pada waktu kontak 40 menit diperoleh persentase penurunan bakteri Coliform hingga 98,83%, yaitu dari >160.000/100 mL menjadi 1.866/100 mL dengan residu klor 97,5 ppm. ABSTRACT Calcium hypochlorite of hospital wastewater serves as disinfectant, however, inappropriate dose of it will lead to the formation of Trihalomethane (THMs which is toxic and carcinogenic. The value of MPN Coliform of wastewater in X hospital Samarinda is >160.000 MPN / 100 mL with residual chlorine 0 ppm. This research aims at determining the optimum dose of calcium hypochlorite usage by using Breakpoint Chlorination curve and its effect to Coliform decrease. Further, the analysis is done by employing iodometric titration and the amount of Coliform

  2. Syntheses, crystal structure, and electronic properties of the five ABaMQ{sub 4} compounds RbBaPS{sub 4}, CsBaPS{sub 4}, CsBaVS{sub 4}, RbBaVSe{sub 4}, and CsBaVSe{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Mesbah, Adel [Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3113 (United States); ICSM, UMR 5257 CEA / CNRS / UM / ENSCM, Site de Marcoule-Bâtiment 426, BP 17171, 30207 Bagnols-sur-Cèze Cedex (France); Prakash, Jai [Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3113 (United States); Rocca, Dario; Lebègue, Sébastien [Laboratoire de Cristallographie, Résonance Magnétique, et Modélisations CRM2 (UMR UHP-CNRS 7036), Faculté des Sciences et Techniques, Université de Lorraine, BP 70239, Boulevard des Aiguillettes, 54506 Vandoeuvre-lès-Nancy Cedex (France); Beard, Jessica C.; Lewis, Benjamin A. [Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3113 (United States); Ibers, James A., E-mail: ibers@chem.northwestern.edu [Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208-3113 (United States)

    2016-01-15

    Five new compounds belonging to the ABaMQ{sub 4} family were synthesized by solid-state chemistry at 1123 K. The compounds RbBaPS{sub 4}, CsBaPS{sub 4}, CsBaVS{sub 4}, RbBaVSe{sub 4}, and CsBaVSe{sub 4} are isostructural and have the TlEuPS{sub 4} structure type. They crystallize in space group D{sup 16}{sub 2h} – Pnma of the orthorhombic system. Their structure consists isolated MQ{sub 4} tetrahedra separated by A and Ba atoms to form a salt-like structure. Density Functional Theory (DFT) calculations of the electronic structures with the use of the HSE functional suggest that the compounds are semiconductors with calculated band gaps of 3.3 eV (RbBaPS{sub 4}), 3.4 eV (CsBaPS{sub 4}), 2.3 eV (CsBaVS{sub 4}), and 1.6 eV (RbBaVSe{sub 4}). - Graphical abstract: General view of the ABaMQ{sub 4} structure down the a axis. - Highlights: • Five new ABaMQ{sub 4} compounds were synthesized by solid-state chemistry at 1123 K. • RbBaPS{sub 4}, CsBaPS{sub 4}, CsBaVS{sub 4}, RbBaVSe{sub 4}, and CsBaVSe{sub 4} have the TlEuPS{sub 4} structure type. • The compounds are semiconductors with calculated band gaps ranging from 1.6 to 3.4 eV.

  3. Leptonic B Decays at BaBar

    Energy Technology Data Exchange (ETDEWEB)

    Monorchio, Diego; /INFN, Naples /Naples U.

    2011-09-13

    The authors will present the most recent results on leptonic B decays B{sup {+-}(0)} {yields} K*{sup {+-}(0)} {nu}{bar {nu}} and B{sup {+-}} {yields} {mu}{sup {+-}}{nu}, based on the data collected by the BaBar detector at PEP-II, an asymmetric e{sup +}e{sup -} collider at the center of mass energy of the {Upsilon}(4S) resonance. Rare B decays have always been a standard probe for New Physics (NP) searches. The very low Standard Model (SM) rate of these decays often make them unaccessible with the present experimental datasets, unless NP effects enhance the rate up to the current experimental sensitivity. Moreover, as NP effects can modify the decay kinematic, particular attention must be payed in order to perform a model independent analysis. A B-Factory provides an unique environment where to investigate these processes. The high number of B{bar B} pairs produced by a B-Factory often allows to approach the needed experimental sensitivity. Moreover, the clean environment and the closed kinematic of the initial state enable to obtaining a very pure sample where to look for these decays.

  4. Leptonic B Decays at BaBar

    Energy Technology Data Exchange (ETDEWEB)

    Baracchini, Elisabetta; /Rome U. /INFN, Rome

    2011-11-10

    We will present the most recent results on leptonic B decays B{sup {+-}(0)} {yields} K*{sup {+-}(0)}{nu}{bar {nu}} and B{sup {+-}} {yields} {mu}{sup {+-}}{nu}, based on the data collected by the BaBar detector at PEP-II, an asymmetric e{sup +}e{sup -} collider at the center of mass energy of the {Upsilon}(4S) resonance. Rare B decays have always been a standard probe for New Physics (NP) searches. The very low Standard Model (SM) rate of these decays often make them unaccessible with the present experimental datasets, unless NP effects enhance the rate up to the current experimental sensitivity. Moreover, as NP effects can modify the decay kinematic, particular attention must be paid in order to perform a model independent analysis. A B-Factory provides an unique environment to investigate these processes. The high number of B{bar B} pairs produced by a B-Factory often allows to approach the needed experimental sensitivity. Moreover, the clean environment and the closed kinematic of the initial state enable to obtaining a very pure sample where to look for these decays.

  5. Ferroelectric relaxor Ba(TiCe)O3

    International Nuclear Information System (INIS)

    Chen Ang; Zhi Jing; Yu Zhi

    2002-01-01

    The dielectric behaviour of Ba(Ti 1-y Ce y )O 3 solid solutions (y=0-0.3) has been studied. A small amount of Ce doping (y=0.02) has weak influence on the dielectric behaviour of Ba(Ti 1-y Ce y )O 3 . With increasing Ce concentration, three phase transitions of pure BaTiO 3 are pinched into one rounded dielectric peak with frequency dispersion, and the relaxation time follows the Vogel-Fulcher relation. The evolution from a normal ferroelectric to a ferroelectric relaxor is emphasized. High strains (S=∼0.1-0.19%) with a small hysteresis under ac fields are obtained in ferroelectric relaxors Ba(Ti 1-y Ce y )O 3 . The physical mechanism of the relaxation process, the pinching effect of the phase transitions and their influence on the ferroelectric and electrostrictive behaviour are discussed. (author)

  6. Operability test report for 211BA flow proportional sampler

    International Nuclear Information System (INIS)

    Weissenfels, R.D.

    1995-01-01

    This operability report will verify that the 211-BA flow proportional sampler functions as intended by design. The sampler was installed by Project W-007H and is part of BAT/AKART for the BCE liquid effluent stream

  7. Ba-bah on tulnud / Liina Jänes

    Index Scriptorium Estoniae

    Jänes, Liina, 1977-

    2005-01-01

    Eesti noori disainereid-sisearhitekte ühendavast disainiagentuurist Ba-bah, selle eesmärgist. Agentuuri juhib Veiko Jääger. Mais 2005 Disaini- ja Arhitektuurigaleriis toimunud Ba-bahi avanäitusest, kus oli väljas töid EKA sisearhitektuuri, klaasi-, ehte- ja sepakunsti eriala üliõpilastelt ning metallmööbli valmistajalt Kalle Pruudenilt

  8. Earth Observation for Biodiversity Assessment (EO-BA)

    CSIR Research Space (South Africa)

    Cho, Moses A

    2012-10-01

    Full Text Available in the Dukuduku coastal forest Earth Observation for Biodiversity Assessment (EO-BA) MA CHO, P DEBBA, R MATHIEU, A RAMOELO, L NAIDOO, H VAN DEVENTER, O MALAHLELA AND R MAIN CSIR Natural Resources and the Environment, Pretoria, South Africa PO Box 395... Observation for Biodiversity Assessment (EO-BA) programme is designed to enhance biodiversity assessment and conservation through the application of earth observation data, with particular focus on the African continent. MISSION To initiate and develop...

  9. X-ray photoelectron spectroscopy study of BaWO{sub 4} and Ba{sub 2}CaWO{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Capece, Angela M., E-mail: acapece@pppl.gov [California Institute of Technology, Pasadena, CA (United States); Polk, James E. [Jet Propulsion Laboratory, Pasadena, CA (United States); Shepherd, Joseph E. [California Institute of Technology, Pasadena, CA (United States)

    2014-12-15

    Highlights: • XPS reference spectra for Ba{sub 2}CaWO{sub 6} and BaWO{sub 4} are presented. • Binding energies of Ba 3d and W 4f lines are 0.7 eV higher for BaWO{sub 4} than Ba{sub 2}CaWO{sub 6}. • Ca 2p spectrum contains two sets of Ca 2p doublets attributed to Ba{sub 2}CaWO{sub 6} and CaCO{sub 3}. - Abstract: XPS reference spectra for Ba{sub 2}CaWO{sub 6} and BaWO{sub 4} are presented, including high resolution spectra of the Ba 3d, W 4f, C 1s, Ca 2p, and O 1s lines. The peak locations and full widths at half maximum are also given. The binding energies of the Ba 3d and W 4f lines are 0.7 eV higher for BaWO{sub 4} than for Ba{sub 2}CaWO{sub 6}. The Ca 2p spectrum contains two sets of Ca 2p doublets that were attributed to Ba{sub 2}CaWO{sub 6} and CaCO{sub 3}.

  10. Thermochemical investigations into the system Y-Ba-Cu-O

    International Nuclear Information System (INIS)

    Neuschuetz, D.; Zimmermann, E.; Hack, K.; Boudene, A.; Mohammad, A.

    1992-01-01

    For a consistent thermodynamic description of the quaternary system Y-Ba-Cu-O, the binary and ternary subsystems must be known. The metallic binaries and the ternary system Y-Ba-Cu have been evaluated by the authors. Discrepancies within the Cu-O system made a thorough experimental re-investigation necessary, leading to a new consistent thermodynamic data set for copper-oxygen which can now serve as a basis for the description of phase equilibria of all high temperature superconductors. Extensive experimental work on the ternaries Y-Cu-O and Ba-Cu-O, which are oxygen partial pressure dependent, revealed liquid phases down to 790degC. The ternary Y-Ba-O could be described more easily on the basis of literature values and present experimental results, because it does not contain any liquid phases at relevant temperatures. The representation of the quaternary Y-Ba-Cu-O is complicated both by its dependence on the oxygen potential and the existence of liquid oxide phases. In contrast to common practice, the present investigations had to start from Cu-free Ba-Y-O in order to avoid unknown liquid phases in the experiments. The present results being insufficient for a complete description of the quaternary system, the work is being continued within an EC joint research project. (orig.) With 84 refs., 8 tabs., 47 figs [de

  11. CONTRAST STUDY ON CT AND BA IN DIAGNOSIS OF PATIENTS WITH ATHEROTHROMBOTIC BRAIN INFARCTION

    Institute of Scientific and Technical Information of China (English)

    Mingshun Liu; Haixiang Gao; Xiaomei Fu; Po Ma

    2007-01-01

    Objectives: To explore applied value on CT and BA in diagnosis of patients with atherothrombotic brain infarction. Methods:CT and BA were examined in 246 patients with atherothrombotic brain infarction. Results:The different change of CT and BA were showed in 246 patients with atherothrombotic brain infarction. Conclusions: There were separately different advantage and shortcoming in CT and BA in diagnosis of atherothrombotic brain infarction. The value of clinical application of BA was important in diagnosis of atherothrombotic brain infarction.

  12. Nuclear charge radii and nuclear moments of neutron deficient Ba isotopes from high resolution laser spectroscopy

    International Nuclear Information System (INIS)

    Nowicki, G.; Bekk, K.; Goering, S.; Hanser, A.; Rebel, H.; Schatz, G.

    1978-07-01

    Isotope shifts and hyperfine structure of the BaI 6s 2 1 S 0 -6s6p 1 P 1 transitions (lambda = 553.6 nm) in neutron deficient Ba nuclides (N 131 Ba, 128 Ba, in addition to remeasurements of all stable Ba nuclides. The extracted values of delta 2 >, the observed odd-even staggering and the nuclear moments are discussed in the light of other theoretical and experimental nuclear structure studies of the region 50 [de

  13. Metaplasia mieloide do baço na Ancilostomose

    Directory of Open Access Journals (Sweden)

    W. O. Cruz

    1934-06-01

    Full Text Available Pesquizamos, no figado e baço de dez casos puros de ancilostomose, elementos hemocitopoieticos; verificamos o peso do baço em 23 casos de individuos com idades compreendidas entre 3 e 60 anos; não encontramos, em nenhum caso, celulas hemoformadoras no figado. Em sete casos, encontramos, no baço, elementos da série vermelha em adiantado estado de evolução (eritroblastos ortocromaticos de nucleo picnotico. Em alguns destes casos observamos megacariocitos e numerosos mielocitos eosinofilos. Os tres casos que não apresentavam metaplasia mieloide no baço, eram os de individuos acima de 50 anos de idade. Entretanto, em outro caso de um individuo com 59 anos esta metaplasia foi verificada. Em individuos acima de 20 anos, o peso médio do baço, em nove casos, mostrou-se igual ao peso normal. Em 14 casos, compreendidos entre 3 e 14 anos, o peso deste orgão foi sempre sensivelmente mais elevado que nos normais de idade correspondente. Estes resultados sugerem a possibilidade de ser a metaplasia mieloide responsavel pelos aumentos de pezo nos baços de individuos jovens, vitimados pela anemia ancilostomica. A notavel proliferação dos eritroblastos ortocromaticos mostra que o grão e a rapidez da regeneração sanguinea, após a administração de ferro, são devidos, essencialmente, á grande quantidade de hemoglobina já preformada no baço e na medula ossea dos organismos ancilostomados.

  14. Operability test procedure for 211BA flow proportional sampler

    International Nuclear Information System (INIS)

    Weissenfels, R.D.

    1994-01-01

    The purpose of this operability test procedure (OTP) is to verify the 211-BA flow proportional sampler system and components function correctly as intended by design. System test will include the sampling system, all associated instrumentation, and Facility Process Monitor and Control System (FPMCS). The combined chemical sewer stream from B Plant flows through sump 211BA-SMP-01 located in 211-BA and is continuously monitored for gamma and beta radiation and pH. 211-BA has been upgraded to include a flow proportional sampler. A specified sample volume will be withdrawn at programmed intervals from the 211BA sump and deposited in a 19 liter plastic carboy. The sampler will be programmed per the vendor installation and operations manual by B Plant instrument maintenance personnel. Samples will be taken during five consecutive sample cycles with the sample volumes and sample frequencies recorded for comparison purposes. Additional tests related to the sampler include the alarm circuitry for loss of power and failure to obtain sample

  15. Thermoelectric properties of doped BaHfO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Dixit, Chandra Kr., E-mail: ckparadise@gmail.com, E-mail: sharmarameshfgiet@gmail.com [Dept. of Physics, Dr. Shakuntala Misra National Rehabilitation University, Lucknow-229001, U.P India (India); Bhamu, K. C. [Department of Physics, Goa University, Goa-403 206 (India); Sharma, Ramesh, E-mail: ckparadise@gmail.com, E-mail: sharmarameshfgiet@gmail.com [Dept. of Physics, Feroze Gandhi Institute of Engineering & Technology, Raebareli-229001, U.P India (India)

    2016-05-06

    We have studied the structural stability, electronic structure, optical properties and thermoelectric properties of doped BaHfO{sub 3} by full potential linearized augmented plane wave (FP-LAPW) method. The electronic structure of BaHfO{sub 3} doped with Sr shows enhances the indirect band gaps of 3.53 eV, 3.58 eV. The charge density plots show strong ionic bonding in Ba-Hf, and ionic and covalent bonding between Hf and O. Calculations of the optical spectra, viz., the dielectric function, refractive index and extinction coefficient are performed for the energy range are calculated and analyzed. Thermoelectric properties of semi conducting are also reported first time. The doped BaHfO{sub 3} is approximately wide band gap semiconductor with the large p-type Seebeck coefficient. The power factor of BaHfO{sub 3} is increased with Sr doping, decreases because of low electrical resistivity and thermal conductivity.

  16. An approach to WWER fuels with BaCo

    International Nuclear Information System (INIS)

    Marino, A.; Demarco, G.

    2008-01-01

    BaCo is a code for the simulation of the behaviour of a nuclear fuel rod under operation conditions. BaCo, a quasi 2D code based on a finite differences scheme, has been used for simulating PHWR, CANDU, PWR, BWR, MOX, WWER, and experimental fuel rods. We improve the performance of BaCo with a set of tools based on the method of finite elements for 3D analysis of the stress-strain state. We can simulate any UO 2 pellet geometry. Standard WWER-440 fuel assemblies irradiated in the Kola-3 reactor of the CRP FUMEX II of the IAEA were the first WWER simulations with BaCo. We find a very good agreement among our calculations, the experimental results and other qualified fuel codes. We present the BaCo code and our results for PWR and WWER fuels of the CRP FUMEX II, the 3D analysis of WWER fuel pellet and the projections of these results with the Argentinean nuclear fuels development. (authors)

  17. Thin film hybrid Josephson junctions with Co doped Ba-122

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Stefan; Doering, Sebastian; Schmidl, Frank; Tympel, Volker; Grosse, Veit; Seidel, Paul [Friedrich-Schiller-Universitaet Jena, Institut fuer Festkoerperphysik, Helmholtzweg 5, 07743 Jena (Germany); Haindl, Silvia; Iida, Kazumasa; Kurth, Fritz; Holzapfel, Bernhard [IFW Dresden, Institut fuer Metallische Werkstoffe, Helmholtzstrasse 20, 01069 Dresden (Germany); Moench, Ingolf [IFW Dresden, Institut fuer Integrative Nanowissenschaften, Helmholtzstrasse 20, 01069 Dresden (Germany)

    2011-07-01

    Josephson junctions are a strong tool to investigate fundamental superconducting properties, such as gap behaviour, dependencies from external fields and the order parameter symmetry. Finding secure values enables the possibility of theoretical descriptions to understand the physical processes within the new iron-based superconductors. Based on Co-doped BaFe{sub 2}As{sub 2} (Ba-122) layers produced via pulsed laser deposition (PLD) on (La,Sr)(Al,Ta)O{sub 3} substrates, we manufactured superconductor-normal conductor-superconductor (S-N-S) junctions structures by using photolithography, ion beam etching as well as insulating SiO{sub 2} layers. We present working Ba-122/Au/PbIn thin film Josephson junctions with different contact areas and barrier thicknesses, their temperature dependence and response to microwave irradiation. The calculated I{sub c}R{sub N} product is in the range of a couple of microvolts.

  18. The BaBar instrumented flux return performance: lessons learned

    CERN Document Server

    Anulli, F; Baldini, R; Band, H R; Bionta, R; Brau, J E; Brigljevic, V; Buzzo, A; Calcaterra, A; Carpinelli, M; Cartaro, C; Cavallo, N; Crosetti, G; De Nardo, Gallieno; De Sangro, R; Eichenbaum, A; Fabozzi, F; Falciai, D; Ferrarotto, F; Ferroni, F; Finocchiaro, G; Forti, F; Frey, R; Gatto, C; Graug; Iakovlev, N I; Iwasaki, M; Johnson, J R; Lange, D J; Lista, L; Lo Vetere, M; Lü, C; Macri, M; Messner, R; Moore, T B; Morganti, S; Neal, H; Neri, N; Palano, A; Paoloni, E; Paolucci, P; Passaggio, S; Pastore, F C; Patteri, P; Peruzzi, I; Piccolo, D; Piccolo, M; Piredda, G; Robutti, E; Roodman, A; Santroni, A; Sciacca, C; Sinev, N B; Soha, A; Strom, D; Tosi, S; Vavra, J; Wisniewski, W J; Wright, D M; Xie, Y; Zallo, A

    2002-01-01

    The BaBar Collaboration has operated an instrumented flux return (IFR) system covering over 2000 m sup 2 with resistive plate chambers (RPCs) for nearly 3 years. The chambers are constructed of bakelite sheets separated by 2 mm. The inner surfaces are coated with linseed oil. This system provides muon and neutral hadron detection for BaBar. Installation and commissioning were completed in 1998, and operation began mid-year 1999. While initial performance of the system reached design, over time, a significant fraction of the RPCs demonstrated significant degradation, marked by increased currents and reduced efficiency. A coordinated effort of investigations have identified many of the elements responsible for the degradation. This article presents our current understanding of the aging process of the BaBar RPCs along with the action plan to combat performance degradation of the IFR system.

  19. Concentrations of Se, Ba, Zn and Mn in Brazil nuts

    Energy Technology Data Exchange (ETDEWEB)

    Armelin, Maria José A.; Maihara, Vera A.; Cardoso, Paulo S.; Saiki, Mitiko [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Cozollino, Silvia M.F., E-mail: marmelin@ipen.br, E-mail: vmaihara@ipen.br, E-mail: msaiki@ipen.br, E-mail: pscsilva@ipen.br, E-mail: smfcozzo@usp.br [Universidade de São Paulo (USP), SP (Brazil). Faculdade de Ciências Farmacêuticas

    2017-07-01

    The concentrations of Se, Ba, Zn and Mn were determined in samples of Brazil nuts collected in two ways: a) in a production farm predominantly for export and, b) in various points of sale from different regions of Brazil. Instrumental neutron activation analysis was the analytical technique used in this study. Results indicate that the concentrations of Se and Ba varied greatly among the Brazil nut samples analyzed. This large variability may be related to the soil characteristics from which the nuts were produced. An inverse correlation was observed between the concentrations of Se and Ba. On the other hand, the concentrations of Zn and Mn did not show significant differences among these samples. (author)

  20. Concentrations of Se, Ba, Zn and Mn in Brazil nuts

    International Nuclear Information System (INIS)

    Armelin, Maria José A.; Maihara, Vera A.; Cardoso, Paulo S.; Saiki, Mitiko; Cozollino, Silvia M.F.

    2017-01-01

    The concentrations of Se, Ba, Zn and Mn were determined in samples of Brazil nuts collected in two ways: a) in a production farm predominantly for export and, b) in various points of sale from different regions of Brazil. Instrumental neutron activation analysis was the analytical technique used in this study. Results indicate that the concentrations of Se and Ba varied greatly among the Brazil nut samples analyzed. This large variability may be related to the soil characteristics from which the nuts were produced. An inverse correlation was observed between the concentrations of Se and Ba. On the other hand, the concentrations of Zn and Mn did not show significant differences among these samples. (author)

  1. Growth and scintillation properties of BaMgF4

    International Nuclear Information System (INIS)

    Yanagida, Takayuki; Kawaguchi, Noriaki; Fujimoto, Yutaka; Sugiyama, Makoto; Furuya, Yuki; Kamada, Kei; Yokota, Yuui; Yoshikawa, Akira; Chani, Valery

    2010-01-01

    By using the micro-pulling down (μ-PD) method, the barium magnesium fluoride (BaMgF 4 ) single crystalline scintillator was produced. The crystal was cut and mirror polished to the physical dimensions of 1x2x10 mm 3 for examination of scintillation properties. BaMgF 4 demonstrated ∼70% transmittance in wavelength range above 170 nm, and strong emission peaking around 205 nm was observed under X-ray excitation. The absolute light yield of BaMgF 4 was 1300±100 ph/MeV, and the decay time profile showed two components as 0.57±0.01 (70%) and 2.2±0.31 (30%) ns at room temperature.

  2. Synthesis of BaTiO3 nanoparticles from TiO2-coated BaCO3 particles derived using a wet-chemical method

    Directory of Open Access Journals (Sweden)

    Yuuki Mochizuki

    2014-03-01

    Full Text Available BaCO3 particles coated with amorphous TiO2 precursor are prepared by a wet chemical method to produce BaTiO3 nanoparticles at low temperatures. Subsequently, we investigate the formation behavior of BaTiO3 particles and the particle growth behavior when the precursor is subjected to heat treatment. The state of the amorphous TiO2 coating on the surface of BaCO3 particles depends on the concentration of NH4HCO3, and the optimum concentration is found to be in the range 0.5–1.0 M. Thermogravimetric curves of the BaCO3 particles coated with the TiO2 precursor, prepared from BaCO3 particles of various sizes, show BaTiO3 formation occurring mainly at 550–650 °C in the case of fine BaCO3 particles. However, as evidenced from the curves, the temperature of formation of BaTiO3 shifts to higher values with an increase in the size of the BaCO3 particles. The average particle size of single phase BaTiO3 at heat-treatment temperature of 650–900 °C is observed to be in the range 60–250 nm.

  3. The interaction of NO2 with BaO: from cooperative adsorption to Ba(NO3)2 formation

    International Nuclear Information System (INIS)

    Yi, Cheol-Woo W.; Kwak, Ja Hun H.; Szanyi, Janos

    2007-01-01

    The effect of water on the morphology of BaO/Al2O3-based NOx storage materials was investigated using Fourier transform infrared spectroscopy, temperature programmed desorption, and time-resolved synchrotron X-ray diffraction techniques. The results of this multi-spectroscopy study reveal that, in the presence of water, surface Ba-nitrates convert to bulk nitrates, and water facilitates the formation of large Ba(NO3)2 particles. The conversion of surface to bulk Ba-nitrates is completely reversible, i.e. after the removal of water from the storage material a significant fraction of the bulk nitrates re-convert to surface nitrates. NO2 exposure of a H2O-containing (wet) BaO/Al2O3 sample results in the formation of nitrites and bulk nitrates exclusively, i.e. no surface nitrates form. After further exposure to NO2, the nitrites completely convert to bulk nitrates. The amount of NOx taken up by the storage material is, however, essentially unaffected by the presence of water, regardless of whether the water was dosed prior to or after NO2 exposure. Based on the results of this study we are now able to explain most of the observations reported in the literature on the effect of water on NOx uptake on similar storage materials

  4. Scintillation and radiation damage of doped BaF2 crystals

    International Nuclear Information System (INIS)

    Gong Zufang; Xu Zizong; Chang Jin

    1992-01-01

    The emission spectra and the radiation damage of BaF 2 crystals doped Ce and Dy have been studied. The results indicate that the doped BaF 2 crystals have the intrinsic spectra of impurity besides the intrinsic spectra of BaF 2 crystals. The crystals colored and the transmissions decrease with the concentration of impurity in BaF 2 crystals after radiation by γ-ray of 60 Co. The doped Ce BaF 2 irradiated by ultraviolet has faster recover of transmissions but for doped Dy the effect is not obvious. The radiation resistance is not good as pure BaF 2 crystals

  5. History of the Balkan Stomatological Society (BaSS

    Directory of Open Access Journals (Sweden)

    Todorović Ljubomir

    2014-11-01

    Full Text Available Some of the main activities of the Balkan Stomatological Society (BaSS over a rich 19-year history are presented. These activities have been aimed at improving oral health care provided by the dentists throughout the Balkans, and to establish ties of friendship and collaboration between researchers and clinicians in this region, creating a foundation for mutual understanding and peace. To accomplish these goals, the BaSS annually organizes congresses and publishes a scientific journal, beside many other activities, such as public oral health promotion, bringing into accordance study programmes and curricula, supporting student exchange programmes, etc.

  6. Development of BaSO4:Eu thermoluminescence phosphor

    International Nuclear Information System (INIS)

    Madhusoodanan, U.; Jose, M.T.; Lakshmanan, A.R.

    1999-01-01

    A highly sensitive thermoluminescence (TL) phosphor based on BaSO 4 :Eu was developed following the coprecipitation technique and firing in argon atmosphere at 1123 K. Photoluminescence studies confirm that firing in argon atmosphere instead of air increased the incorporation of Eu ions in 2+ valence state. At low γ-ray doses, its TL sensitivity is nearly 2 to 3 times higher than that of CaSO 4 :Dy phosphor. The other salient features of this BaSO 4 :Eu TL phosphor are a constant glow curve shape and a nearly linear γ-ray dose response

  7. The Danish Microbiology Database (MiBa) 2010 to 2013.

    Science.gov (United States)

    Voldstedlund, M; Haarh, M; Mølbak, K

    2014-01-09

    The Danish Microbiology Database (MiBa) is a national database that receives copies of reports from all Danish departments of clinical microbiology. The database was launched in order to provide healthcare personnel with nationwide access to microbiology reports and to enable real-time surveillance of communicable diseases and microorganisms. The establishment and management of MiBa has been a collaborative process among stakeholders, and the present paper summarises lessons learned from this nationwide endeavour which may be relevant to similar projects in the rapidly changing landscape of health informatics.

  8. Development of BaSO sub 4 :Eu thermoluminescence phosphor

    CERN Document Server

    Madhusoodanan, U; Lakshmanan, A R

    1999-01-01

    A highly sensitive thermoluminescence (TL) phosphor based on BaSO sub 4 :Eu was developed following the coprecipitation technique and firing in argon atmosphere at 1123 K. Photoluminescence studies confirm that firing in argon atmosphere instead of air increased the incorporation of Eu ions in 2+ valence state. At low gamma-ray doses, its TL sensitivity is nearly 2 to 3 times higher than that of CaSO sub 4 :Dy phosphor. The other salient features of this BaSO sub 4 :Eu TL phosphor are a constant glow curve shape and a nearly linear gamma-ray dose response.

  9. Phase relationships in the BaO-Ga2O3-Ta2O5 system and the structure of Ba6Ga21TaO40.

    Science.gov (United States)

    Cao, Jiang; Yu, Xiaodi; Kuang, Xiaojun; Su, Qiang

    2012-07-16

    Phase relationships in the BaO-Ga(2)O(3)-Ta(2)O(5) ternary system at 1200 °C were determined. The A(6)B(10)O(30) tetragonal tungsten bronze (TTB) related solution in the BaO-Ta(2)O(5) subsystem dissolved up to ~11 mol % Ga(2)O(3), forming a ternary trapezoid-shaped TTB-related solid solution region defined by the BaTa(2)O(6), Ba(1.1)Ta(5)O(13.6), Ba(1.58)Ga(0.92)Ta(4.08)O(13.16), and Ba(6)GaTa(9)O(30) compositions in the BaO-Ga(2)O(3)-Ta(2)O(5) system. Two ternary phases Ba(6)Ga(21)TaO(40) and eight-layer twinned hexagonal perovskite solid solution Ba(8)Ga(4-x)Ta(4+0.6x)O(24) were confirmed in the BaO-Ga(2)O(3)-Ta(2)O(5) system. Ba(6)Ga(21)TaO(40) crystallized in a monoclinic cell of a = 15.9130(2) Å, b = 11.7309(1) Å, c = 5.13593(6) Å, β = 107.7893(9)°, and Z = 1 in space group C2/m. The structure of Ba(6)Ga(21)TaO(40) was solved by the charge flipping method, and it represents a three-dimensional (3D) mixed GaO(4) tetrahedral and GaO(6)/TaO(6) octahedral framework, forming mixed 1D 5/6-fold tunnels that accommodate the Ba cations along the c axis. The electrical property of Ba(6)Ga(21)TaO(40) was characterized by using ac impedance spectroscopy.

  10. Praseodymium valency from crystal structure in Pr-Ba-Cu-O and (Y-Pr)-Ba-Cu-O single crystals

    International Nuclear Information System (INIS)

    Collin, G.; Albouy, P.A.; Monod, P.; Ribault, M.

    1990-01-01

    The substitution of Pr to Y leads to materials with a general formula (Y 1-v Pr v ) (Ba 2-x Pr x ) (Cu 3-y vac y ) O 6+x/2-y+z and with a structural transition around v + x' ∼ 0.5. For v + x 0.5 the crystals are tetragonal, La 1.5 Ba 1.5 Cu 3 O 7±z type, with the characteristic tri-twinning of this phase. The Pr valency, in the range 3-3.2 + depending on preparation conditions, is determined from interatomic distances. Orthorhombic crystals of Pr Ba Cu O prepared at high temperatures exhibit a high amount of defects, y ∼ 0.25 on the Cu(1) site and are semiconductors with a T -1/4 activation law attributed to the praseodymium valence fluctuation

  11. Punta Pitt, Galapagos Ba/Ca Data for 1963-1982

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — File contains Ba/Ca data (in mmol/mol) presented by Lea et al. (1989). Samples were measured at the Massachusetts Institute of Technology by D. Lea. Ba...

  12. Growth and characterization of acentric BaHf(BO{sub 3}){sub 2} and BaZr(BO{sub 3}){sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Mączka, Mirosław, E-mail: m.maczka@int.pan.wroc.pl [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, P.O. Box 1410, 50-950 Wrocław 2 (Poland); Szymborska-Małek, Katarzyna; Gągor, Anna [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, P.O. Box 1410, 50-950 Wrocław 2 (Poland); Majchrowski, Andrzej [Institute of Applied Physics, Military University of Technology, 2 Kaliskiego Str., 00-908 Warszawa (Poland)

    2015-05-15

    Growth, single crystal X-ray diffraction, polarized Raman and infrared (IR) studies of BaHf(BO{sub 3}){sub 2} are presented. Raman and IR spectra of polycrystalline BaZr(BO{sub 3}){sub 2} are also reported to facilitate assignment of modes. BaHf(BO{sub 3}){sub 2} borate crystallizes in trigonal system, space group R3c, with lattice parameters: a=5.1540(4) Å, c=33.901(3) Å. It accommodates dolomite-like structure doubled in the c direction, which is built of alternating layers of HfO{sub 6} octahedra and BaO{sub 6} distorted trigonal prisms that are connected through borate groups. The obtained structural as well as spectroscopic data show that BaHf(BO{sub 3}){sub 2} is isostructural with BaZr(BO{sub 3}){sub 2} and the deviations from centrosymmetry is small. - Graphical abstract: Arrangement of BO{sub 3} groups in BaHf(BO{sub 3}){sub 2} along the c direction in one unit cell. Dark and light blue denote different borate groups. - Highlights: • BaHf(BO{sub 3}){sub 2} single crystals were grown. • X-ray diffraction showed that this borate crystallizes in the acentric R3c structure. • Raman and IR spectra were measured for BaHf(BO{sub 3}){sub 2} and BaZr(BO{sub 3}){sub 2}, respectively. • Assignment of modes is proposed.

  13. BaM bentonite and some of its properties

    International Nuclear Information System (INIS)

    Matal, Oldřich; Vávra Michal; Kachlík, Martin; Maca, Karel; Kotnour, Petr; Pospíšková, Ilona

    2018-01-01

    BaM bentonite is lime-magnesium bentonite of domestic origin. Its properties were measured experimentally with focus on the following parameters: composition, morphology and particle size distribution, powder bulk density, powder pressing parameters, shear strength, and water saturation. The findings will find use in nuclear safety assessments of engineered bentonite barriers in underground nuclear waste disposal facilities. (orig.)

  14. Generator Coordinate Method Analysis of Xe and Ba Isotopes

    Science.gov (United States)

    Higashiyama, Koji; Yoshinaga, Naotaka; Teruya, Eri

    Nuclear structure of Xe and Ba isotopes is studied in terms of the quantum-number projected generator coordinate method (GCM). The GCM reproduces well the energy levels of high-spin states as well as low-lying states. The structure of the low-lying states is analyzed through the GCM wave functions.

  15. Superconductivity of Ba8Si46-xGax clathrates

    Science.gov (United States)

    Li, Yang; Zhang, Ruihong; Chen, Ning; Ma, Xingqiao; Cao, Guohui; Luo, Z. P.; Hu, C. R.; Ross, Joseph H., Jr.

    2007-03-01

    We have presented a combined experimental and theoretical study of the effect of Gallium substitution on the superconductivity of the type I clathrate Ba8Si46-xGax. In Ga-doped clathrates, the Ga state is found to be strongly hybridized with the cage conduction-band state. Ga substitution results in a shift toward to a lower energy, a decrease of density of states at Fermi level, a lowering of the carrier concentration and a breakage of integrity of the sp3 hybridized networks. These play key roles in the suppression of superconductivity. For Ba8Si40Ga6, the onset of the superconducting transition occurs at Tc=3.3 K. The investigation of the magnetic superconducting state shows that Ba8Si40Ga6 is a type II superconductor. The critical magnetic fields were measured to be Hc1=35 Oe and Hc2=8.5 kOe. Our estimate of the lectron-phonon coupling reveals that Ba8Si40Ga6 is a moderate phonon-mediated BCS superconductor.

  16. Y-Ba-Cu-O superconducting film on oxidized silicon

    International Nuclear Information System (INIS)

    Gupta, R.P.; Khokle, W.S.; Dubey, R.C.; Singhal, S.; Nagpal, K.C.; Rao, G.S.T.; Jain, J.D.

    1988-01-01

    We report thick superconducting films of Y-Ba-Cu-O on oxidized silicon substrates. The critical temperatures for onset and zero resistance are 96 and 77 K, respectively. X-ray diffraction analysis predicts 1, 2, 3 composition and orthorhombic phase of the film

  17. The Danish Microbiology Database (MiBa) 2010 to 2013

    DEFF Research Database (Denmark)

    Voldstedlund, M; Haarh, M; Mølbak, K

    2014-01-01

    The Danish Microbiology Database (MiBa) is a national database that receives copies of reports from all Danish departments of clinical microbiology. The database was launched in order to provide healthcare personnel with nationwide access to microbiology reports and to enable real-time surveillance...

  18. The BaBar detector: Upgrades, operation and performance

    Energy Technology Data Exchange (ETDEWEB)

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; del Amo Sanchez, P.; Gaillard, J. -M.; Hicheur, A.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prudent, X.; Robbe, P.; Tisserand, V.; Zghiche, A.; Grauges, E.; Garra Tico, J.; Lopez, L.; Martinelli, M.; Palano, A.; Pappagallo, M.; Pompili, A.; Chen, G. P.; Chen, J. C.; Qi, N. D.; Rong, G.; Wang, P.; Zhu, Y. S.; Eigen, G.; Stugu, B.; Sun, L.; Abrams, G. S.; Battaglia, M.; Borgland, A. W.; Breon, A. B.; Brown, D. N.; Button-Shafer, J.; Cahn, R. N.; Charles, E.; Clark, A. R.; Day, C. T.; Furman, M.; Gill, M. S.; Groysman, Y.; Jacobsen, R. G.; Kadel, R. W.; Kadyk, J. A.; Kerth, L. T.; Kolomensky, Yu. G.; Kral, J. F.; Kukartsev, G.; LeClerc, C.; Levi, M. E.; Lynch, G.; Merchant, A. M.; Mir, L. M.; Oddone, P. J.; Orimoto, T. J.; Osipenkov, I. L.; Pripstein, M.; Roe, N. A.; Romosan, A.; Ronan, M. T.; Shelkov, V. G.; Suzuki, A.; Tackmann, K.; Tanabe, T.; Wenzel, W. A.; Zisman, M.; Barrett, M.; Bright-Thomas, P. G.; Ford, K. E.; Harrison, T. J.; Hart, A. J.; Hawkes, C. M.; Knowles, D. J.; Morgan, S. E.; O' Neale, S. W.; Penny, R. C.; Smith, D.; Soni, N.; Watson, A. T.; Watson, N. K.; Goetzen, K.; Held, T.; Koch, H.; Kunze, M.; Lewandowski, B.; Pelizaeus, M.; Peters, K.; Schmuecker, H.; Schroeder, T.; Steinke, M.; Fella, A.; Antonioli, E.; Boyd, J. T.; Chevalier, N.; Cottingham, W. N.; Foster, B.; Mackay, C.; Walker, D.; Abe, K.; Asgeirsson, D. J.; Cuhadar-Donszelmann, T.; Fulsom, B. G.; Hearty, C.; Knecht, N. S.; Mattison, T. S.; McKenna, J. A.; Thiessen, D.; Khan, A.; Kyberd, P.; McKemey, A. K.; Randle-Conde, A.; Saleem, M.; Sherwood, D. J.; Teodorescu, L.; Blinov, V. E.; Bukin, A. D.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Korol, A. A.; Kravchenko, E. A.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Telnov, V. I.; Todyshev, K. Yu.; Yushkov, A. N.; Best, D. S.; Bondioli, M.; Bruinsma, M.; Chao, M.; Curry, S.; Eschrich, I.; Kirkby, D.; Lankford, A. J.; Mandelkern, M.; Martin, E. C.; McMahon, S.; Mommsen, R. K.; Stoker, D. P.; Abachi, S.; Buchanan, C.; Hartfiel, B. L.; Weinstein, A. J. R.; Atmacan, H.; Foulkes, S. D.; Gary, J. W.; Layter, J.; Liu, F.; Long, O.; Shen, B. C.; Vitug, G. M.; Wang, K.; Yasin, Z.; Zhang, L.; Hadavand, H. K.; Hill, E. J.; Paar, H. P.; Rahatlou, S.; Schwanke, U.; Sharma, V.; Berryhill, J. W.; Campagnari, C.; Cunha, A.; Dahmes, B.; Hong, T. M.; Kovalskyi, D.; Kuznetsova, N.; Levy, S. L.; Lu, A.; Mazur, M. A.; Richman, J. D.; Verkerke, W.; Beck, T. W.; Beringer, J.; Eisner, A. M.; Flacco, C. J.; Grillo, A. A.; Grothe, M.; Heusch, C. A.; Kroseberg, J.; Lockman, W. S.; Martinez, A. J.; Nesom, G.; Schalk, T.; Schmitz, R. E.; Schumm, B. A.; Seiden, A.; Spencer, E.; Spradlin, P.; Turri, M.; Walkowiak, W.; Wang, L.; Wilder, M.; Williams, D. C.; Wilson, M. G.; Winstrom, L. O.; Chen, E.; Cheng, C. H.; Doll, D. A.; Dorsten, M. P.; Dvoretskii, A.; Echenard, B.; Erwin, R. J.; Fang, F.; Flood, K.; Hitlin, D. G.; Metzler, S.; Narsky, I.; Oyang, J.; Piatenko, T.; Porter, F. C.; Ryd, A.; Samuel, A.; Yang, S.; Zhu, R. Y.; Andreassen, R.; Devmal, S.; Geld, T. L.; Jayatilleke, S.; Mancinelli, G.; Meadows, B. T.; Mishra, K.; Sokoloff, M. D.; Abe, T.; Antillon, E. A.; Barillari, T.; Becker, J.; Blanc, F.; Bloom, P. C.; Chen, S.; Clifton, Z. C.; Derrington, I. M.; Destree, J.; Dima, M. O.; Ford, W. T.; Gaz, A.; Gilman, J. D.; Hachtel, J.; Hirschauer, J. F.; Johnson, D. R.; Kreisel, A.; Nagel, M.; Nauenberg, U.; Olivas, A.; Rankin, P.; Roy, J.; Ruddick, W. O.; Smith, J. G.; Ulmer, K. A.; van Hoek, W. C.; Wagner, S. R.; West, C. G.; Zhang, J.; Ayad, R.; Blouw, J.; Chen, A.; Eckhart, E. A.; Harton, J. L.; Hu, T.; Toki, W. H.; Wilson, R. J.; Winklmeier, F.; Zeng, Q. L.; Altenburg, D.; Feltresi, E.; Hauke, A.; Jasper, H.; Karbach, M.; Merkel, J.; Petzold, A.; Spaan, B.; Wacker, K.; Brandt, T.; Brose, J.; Colberg, T.; Dahlinger, G.; Dickopp, M.; Eckstein, P.; Futterschneider, H.; Kaiser, S.; Kobel, M. J.; Krause, R.; Müller-Pfefferkorn, R.; Mader, W. F.; Maly, E.; Nogowski, R.; Otto, S.; Schubert, J.; Schubert, K. R.; Schwierz, R.; Sundermann, J. E.; Volk, A.; Wilden, L.; Bernard, D.; Brochard, F.; Cohen-Tanugi, J.; Dohou, F.; Ferrag, S.; Latour, E.; Mathieu, A.; Renard, C.; Schrenk, S.; T' Jampens, S.; Thiebaux, Ch.; Vasileiadis, G.; Verderi, M.; Anjomshoaa, A.; Bernet, R.; Clark, P. J.; Lavin, D. R.; Muheim, F.; Playfer, S.; Robertson, A. I.; Swain, J. E.; Watson, J. E.; Xie, Y.; Andreotti, D.; Andreotti, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Carassiti, V.; Cecchi, A.; Cibinetto, G.; Cotta Ramusino, A.; Evangelisti, F.; Fioravanti, E.; Franchini, P.; Garzia, I.; Landi, L.; Luppi, E.; Malaguti, R.; Negrini, M.; Padoan, C.; Petrella, A.; Piemontese, L.; Santoro, V.; Sarti, A.; Anulli, F.; Baldini-Ferroli, R.; Calcaterra, A.; Finocchiaro, G.; Pacetti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rama, M.; de Sangro, R.; Santoni, M.; Zallo, A.; Bagnasco, S.; Buzzo, A.; Capra, R.; Contri, R.; Crosetti, G.; Lo Vetere, M.; Macri, M. M.; Minutoli, S.; Monge, M. R.; Musico, P.; Passaggio, S.; Pastore, F. C.; Patrignani, C.; Pia, M. G.; Robutti, E.; Santroni, A.; Tosi, S.; Bhuyan, B.; Prasad, V.; Bailey, S.; Brandenburg, G.; Chaisanguanthum, K. S.; Lee, C. L.; Morii, M.; Won, E.; Wu, J.; Adametz, A.; Dubitzky, R. S.; Marks, J.; Schenk, S.; Uwer, U.; Klose, V.; Lacker, H. M.; Aspinwall, M. L.; Bhimji, W.; Bowerman, D. A.; Dauncey, P. D.; Egede, U.; Flack, R. L.; Gaillard, J. R.; Gunawardane, N. J. W.; Morton, G. W.; Nash, J. A.; Nikolich, M. B.; Panduro Vazquez, W.; Sanders, P.; Smith, D.; Taylor, G. P.; Tibbetts, M.; Behera, P. K.; Chai, X.; Charles, M. J.; Grenier, G. J.; Hamilton, R.; Lee, S. -J.; Mallik, U.; Meyer, N. T.; Chen, C.; Cochran, J.; Crawley, H. B.; Dong, L.; Eyges, V.; Fischer, P. -A.; Lamsa, J.; Meyer, W. T.; Prell, S.; Rosenberg, E. I.; Rubin, A. E.; Gao, Y. Y.; Gritsan, A. V.; Guo, Z. J.; Lae, C. K.; Schott, G.; Albert, J. N.; Arnaud, N.; Beigbeder, C.; Breton, D.; Davier, M.; Derkach, D.; Dû, S.; Firmino da Costa, J.; Grosdidier, G.; Höcker, A.; Laplace, S.; Le Diberder, F.; Lepeltier, V.; Lutz, A. M.; Malaescu, B.; Nief, J. Y.; Petersen, T. C.; Plaszczynski, S.; Pruvot, S.; Roudeau, P.; Schune, M. H.; Serrano, J.; Sordini, V.; Stocchi, A.; Tocut, V.; Trincaz-Duvoid, S.; Wang, L. L.; Wormser, G.; Bionta, R. M.; Brigljević, V.; Lange, D. J.; Simani, M. C.; Wright, D. M.; Bingham, I.; Burke, J. P.; Chavez, C. A.; Coleman, J. P.; Forster, I. J.; Fry, J. R.; Gabathuler, E.; Gamet, R.; George, M.; Hutchcroft, D. E.; Kay, M.; Parry, R. J.; Payne, D. J.; Schofield, K. C.; Sloane, R. J.; Touramanis, C.; Azzopardi, D. E.; Bellodi, G.; Bevan, A. J.; Clarke, C. K.; Cormack, C. M.; Di Lodovico, F.; Dixon, P.; George, K. A.; Menges, W.; Potter, R. J. L.; Sacco, R.; Shorthouse, H. W.; Sigamani, M.; Strother, P.; Vidal, P. B.; Brown, C. L.; Cowan, G.; Flaecher, H. U.; George, S.; Green, M. G.; Hopkins, D. A.; Jackson, P. S.; Kurup, A.; Marker, C. E.; McGrath, P.; McMahon, T. R.; Paramesvaran, S.; Salvatore, F.; Vaitsas, G.; Winter, M. A.; Wren, A. C.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Fritsch, M.; Gradl, W.; Griessinger, K.; Hafner, A.; Prencipe, E.; Allison, J.; Alwyn, K. E.; Bailey, D. S.; Barlow, N. R.; Barlow, R. J.; Chia, Y. M.; Edgar, C. L.; Forti, A. C.; Fullwood, J.; Hart, P. A.; Hodgkinson, M. C.; Jackson, F.; Jackson, G.; Kelly, M. P.; Kolya, S. D.; Lafferty, G. D.; Lyon, A. J.; Naisbit, M. T.; Savvas, N.; Weatherall, J. H.; West, T. J.; Williams, J. C.; Yi, J. I.; Anderson, J.; Farbin, A.; Hulsbergen, W. D.; Jawahery, A.; Lillard, V.; Roberts, D. A.; Schieck, J. R.; Simi, G.; Tuggle, J. M.; Blaylock, G.; Dallapiccola, C.; Hertzbach, S. S.; Kofler, R.; Koptchev, V. B.; Li, X.; Moore, T. B.; Salvati, E.; Saremi, S.; Staengle, H.; Willocq, S. Y.; Cowan, R.; Dujmic, D.; Fisher, P. H.; Henderson, S. W.; Koeneke, K.; Lang, M. I.; Sciolla, G.; Spitznagel, M.; Taylor, F.; Yamamoto, R. K.; Yi, M.; Zhao, M.; Zheng, Y.; Klemetti, M.; Lindemann, D.; Mangeol, D. J. J.; Mclachlin, S. E.; Milek, M.; Patel, P. M.; Robertson, S. H.; Biassoni, P.; Cerizza, G.; Lazzaro, A.; Lombardo, V.; Neri, N.; Palombo, F.; Pellegrini, R.; Stracka, S.; Bauer, J. M.; Cremaldi, L.; Eschenburg, V.; Kroeger, R.; Reidy, J.; Sanders, D. A.; Summers, D. J.; Zhao, H. W.; Godang, R.; Brunet, S.; Cote, D.; Nguyen, X.; Simard, M.; Taras, P.; Viaud, B.; Nicholson, H.; Cavallo, N.; De Nardo, G.; Fabozzi, F.; Gatto, C.; Lista, L.; Monorchio, D.; Onorato, G.; Paolucci, P.; Piccolo, D.; Sciacca, C.; Baak, M. A.; Raven, G.; Snoek, H. L.; Jessop, C. P.; Knoepfel, K. J.; LoSecco, J. M.; Wang, W. F.; Allmendinger, T.; Benelli, G.; Brau, B.; Corwin, L. A.; Gan, K. K.; Honscheid, K.; Hufnagel, D.; Kagan, H.; Kass, R.; Morris, J. P.; Rahimi, A. M.; Regensburger, J. J.; Smith, D. S.; Ter-Antonyan, R.; Wong, Q. K.; Blount, N. L.; Brau, J.; Frey, R.; Igonkina, O.; Iwasaki, M.; Kolb, J. A.; Lu, M.; Potter, C. T.; Rahmat, R.; Sinev, N. B.; Strom, D.; Strube, J.; Torrence, E.; Borsato, E.; Castelli, G.; Colecchia, F.; Crescente, A.; Dal Corso, F.; Dorigo, A.; Fanin, C.; Furano, F.; Gagliardi, N.; Galeazzi, F.; Margoni, M.; Marzolla, M.; Michelon, G.; Morandin, M.; Posocco, M.; Rotondo, M.; Simonetto, F.; Solagna, P.; Stevanato, E.; Stroili, R.; Tiozzo, G.; Voci, C.; Akar, S.; Bailly, P.; Ben-Haim, E.; Bonneaud, G.; Briand, H.; Chauveau, J.; Hamon, O.; John, M. J. J.; Lebbolo, H.; Leruste, Ph.; Malclès, J.; Marchiori, G.; Martin, L.; Ocariz, J.; Perez, A.; Pivk, M.; Prendki, J.; Roos, L.; Sitt, S.; Stark, J.; Thérin, G.; Vallereau, A.; Biasini, M.; Covarelli, R.; Manoni, E.; Pennazzi, S.; Pioppi, M.; Angelini, C.; Batignani, G.; Bettarini, S.; Bosi, F.; Bucci, F.; Calderini, G.; Carpinelli, M.; Cenci, R.; Cervelli, A.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Marchiori, G.; Morganti, M.; Morsani, F.; Paoloni, E.; Raffaelli, F.; Rizzo, G.; Sandrelli, F.; Triggiani, G.; Walsh, J. J.; Haire, M.; Judd, D.; Biesiada, J.; Danielson, N.; Elmer, P.; Fernholz, R. E.; Lau, Y. P.; Lu, C.; Miftakov, V.; Olsen, J.; Lopes Pegna, D.; Sands, W. R.; Smith, A. J. S.; Telnov, A. V.; Tumanov, A.; Varnes, E. W.; Baracchini, E.; Bellini, F.; Bulfon, C.; Buccheri, E.; Cavoto, G.; D' Orazio, A.; Di Marco, E.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Gaspero, M.; Jackson, P. D.; Lamanna, E.; Leonardi, E.; Li Gioi, L.; Lunadei, R.; Mazzoni, M. A.; Morganti, S.; Piredda, G.; Polci, F.; del Re, D.; Renga, F.; Safai Tehrani, F.; Serra, M.; Voena, C.; Bünger, C.; Christ, S.; Hartmann, T.; Leddig, T.; Schröder, H.; Wagner, G.; Waldi, R.; Adye, T.; Bly, M.; Brew, C.; Condurache, C.; De Groot, N.; Franek, B.; Geddes, N. I.; Gopal, G. P.; Olaiya, E. O.; Ricciardi, S.; Roethel, W.; Wilson, F. F.; Xella, S. M.; Aleksan, R.; Bourgeois, P.; Emery, S.; Escalier, M.; Esteve, L.; Gaidot, A.; Ganzhur, S. F.; Giraud, P. -F.; Georgette, Z.; Graziani, G.; Hamel de Monchenault, G.; Kozanecki, W.; Langer, M.; Legendre, M.; London, G. W.; Mayer, B.; Micout, P.; Serfass, B.; Vasseur, G.; Yèche, Ch.; Zito, M.; Allen, M. T.; Akre, R.; Aston, D.; Azemoon, T.; Bard, D. J.; Bartelt, J.; Bartoldus, R.; Bechtle, P.; Becla, J.; Benitez, J. F.; Berger, N.; Bertsche, K.; Boeheim, C. T.; Bouldin, K.; Boyarski, A. M.; Boyce, R. F.; Browne, M.; Buchmueller, O. L.; Burgess, W.; Cai, Y.; Cartaro, C.; Ceseracciu, A.; Claus, R.; Convery, M. R.; Coupal, D. P.; Craddock, W. W.; Crane, G.; Cristinziani, M.; DeBarger, S.; Decker, F. J.; Dingfelder, J. C.; Donald, M.; Dorfan, J.; Dubois-Felsmann, G. P.; Dunwoodie, W.; Ebert, M.; Ecklund, S.; Erickson, R.; Fan, S.; Field, R. C.; Fisher, A.; Fox, J.; Franco Sevilla, M.; Fulsom, B. G.; Gabareen, A. M.; Gaponenko, I.; Glanzman, T.; Gowdy, S. J.; Graham, M. T.; Grenier, P.; Hadig, T.; Halyo, V.; Haller, G.; Hamilton, J.; Hanushevsky, A.; Hasan, A.; Hast, C.; Hee, C.; Himel, T.; Hryn' ova, T.; Huffer, M. E.; Hung, T.; Innes, W. R.; Iverson, R.; Kaminski, J.; Kelsey, M. H.; Kim, H.; Kim, P.; Kharakh, D.; Kocian, M. L.; Krasnykh, A.; Krebs, J.; Kroeger, W.; Kulikov, A.; Kurita, N.; Langenegger, U.; Leith, D. W. G. S.; Lewis, P.; Li, S.; Libby, J.; Lindquist, B.; Luitz, S.; Lüth, V.; Lynch, H. L.; MacFarlane, D. B.; Marsiske, H.; McCulloch, M.; McDonald, J.; Melen, R.; Menke, S.; Metcalfe, S.; Messner, R.; Moss, L. J.; Mount, R.; Muller, D. R.; Neal, H.; Nelson, D.; Nelson, S.; Nordby, M.; Nosochkov, Y.; Novokhatski, A.; O' Grady, C. P.; O' Neill, F. G.; Ofte, I.; Ozcan, V. E.; Perazzo, A.; Perl, M.; Petrak, S.; Piemontese, M.; Pierson, S.; Pulliam, T.; Ratcliff, B. N.; Ratkovsky, S.; Reif, R.; Rivetta, C.; Rodriguez, R.; Roodman, A.; Salnikov, A. A.; Schietinger, T.; Schindler, R. H.; Schwarz, H.; Schwiening, J.; Seeman, J.; Smith, D.; Snyder, A.; Soha, A.; Stanek, M.; Stelzer, J.; Su, D.; Sullivan, M. K.; Suzuki, K.; Swain, S. K.; Tanaka, H. A.; Teytelman, D.; Thompson, J. M.; Tinslay, J. S.; Trunov, A.; Turner, J.; van Bakel, N.; van Winkle, D.; Va' vra, J.; Wagner, A. P.; Weaver, M.; Weinstein, A. J. R.; Weber, T.; West, C. A.; Wienands, U.; Wisniewski, W. J.; Wittgen, M.; Wittmer, W.; Wright, D. H.; Wulsin, H. W.; Yan, Y.; Yarritu, A. K.; Yi, K.; Yocky, G.; Young, C. C.; Ziegler, V.; Chen, X. R.; Liu, H.; Park, W.; Purohit, M. V.; Singh, H.; Weidemann, A. W.; White, R. M.; Wilson, J. R.; Yumiceva, F. X.; Sekula, S. J.; Bellis, M.; Burchat, P. R.; Edwards, A. J.; Majewski, S. A.; Meyer, T. I.; Miyashita, T. S.; Petersen, B. A.; Roat, C.; Ahmed, M.; Ahmed, S.; Alam, M. S.; Bula, R.; Ernst, J. A.; Jain, V.; Liu, J.; Pan, B.; Saeed, M. A.; Wappler, F. R.; Zain, S. B.; Gorodeisky, R.; Guttman, N.; Peimer, D.; Soffer, A.; De Silva, A.; Lund, P.; Krishnamurthy, M.; Ragghianti, G.; Spanier, S. M.; Wogsland, B. J.; Eckmann, R.; Ritchie, J. L.; Ruland, A. M.; Satpathy, A.; Schilling, C. J.; Schwitters, R. F.; Wray, B. C.; Drummond, B. W.; Izen, J. M.; Kitayama, I.; Lou, X. C.; Ye, S.; Bianchi, F.; Bona, M.; Gallo, F.; Gamba, D.; Pelliccioni, M.; Bomben, M.; Borean, C.; Bosisio, L.; Cossutti, F.; Della Ricca, G.; Dittongo, S.; Grancagnolo, S.; Lanceri, L.; Poropat, P.; Rashevskaya, I.; Vitale, L.; Vuagnin, G.; Manfredi, P. F.; Re, V.; Speziali, V.; Frank, E. D.; Gladney, L.; Guo, Q. H.; Panetta, J.; Azzolini, V.; Lopez-March, N.; Martinez-Vidal, F.; Milanes, D. A.; Oyanguren, A.; Agarwal, A.; Albert, J.; Banerjee, Sw.; Bernlochner, F. U.; Brown, C. M.; Choi, H. H. F.; Fortin, D.; Fransham, K. B.; Hamano, K.; Kowalewski, R.; Lewczuk, M. J.; Nugent, I. M.; Roney, J. M.; Sobie, R. J.; Back, J. J.; Gershon, T. J.; Harrison, P. F.; Ilic, J.; Latham, T. E.; Mohanty, G. B.; Puccio, E.; Band, H. R.; Chen, X.; Cheng, B.; Dasu, S.; Datta, M.; Eichenbaum, A. M.; Hollar, J. J.; Hu, H.; Johnson, J. R.; Kutter, P. E.; Li, H.; Liu, R.; Mellado, B.; Mihalyi, A.; Mohapatra, A. K.; Pan, Y.; Pierini, M.; Prepost, R.; Scott, I. J.; Tan, P.; Vuosalo, C. O.; von Wimmersperg-Toeller, J. H.; Wu, S. L.; Yu, Z.; Greene, M. G.; Kordich, T. M. B.

    2013-11-01

    The BaBar detector operated successfully at the PEP-II asymmetric e+e- collider at the SLAC National Accelerator Laboratory from 1999 to 2008. This report covers upgrades, operation, and performance of the collider and the detector systems, as well as the trigger, online and offline computing, and aspects of event reconstruction since the beginning of data taking.

  19. Observation of high spin levels in Cs from Ba decay

    Indian Academy of Sciences (India)

    physics pp. 1157–1162. Observation of high spin levels in. 131. Cs from. 131. Ba decay. M SAINATH, DWARAKA RANI RAO*, K VENKATARAMANIAH and P C SOOD. Department of Physics, Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam 515 134, India. £Permanent address: Department of Physics, ...

  20. Enhanced Optical Performance of BaMgAl

    NARCIS (Netherlands)

    Yin, L.J.; Dong, Juntao; Wang, Yinping; Zhang, Bi; Zhou, Zheng Yang; Jian, Xian; Wu, Mengqiang; Xu, Xin; van Ommen, J.R.; Hintzen, H.T.J.M.

    2016-01-01

    Many strategies have been adopted to improve thermal degradation of phosphors. Because of the stability and high transmittance of graphene, here we report a novel method of carbon coating on BaMgAl10O17:Eu2+ (BAM) phosphor particles through chemical vapor

  1. Intermetallic and metal-rich phases in the system Li-Ba-In-N

    International Nuclear Information System (INIS)

    Smetana, Volodymyr; Vajenine, Grigori V.; Kienle, Lorenz; Duppel, Viola; Simon, Arndt

    2010-01-01

    Three new intermetallic phases, BaLi 2.1 In 1.9 , BaLi 1.12 In 0.98 , and BaLi 1.06 In 1.16 and two subnitrides Li 35 In 45 Ba 39 N 9 and LiIn 2 Ba 3 N 0.83 have been synthesized and their crystal structures have been determined. According to single crystal X-ray diffraction data BaLi 2.1 In 1.9 and BaLi 1.12 In 0.98 crystallize with hexagonal symmetry (BaLi 2.1 In 1.9 : P6 3 /mmc, a=10.410(2), c=8.364(2) A, Z=6, V=785.0(2) A 3 ) and BaLi 1.12 In 0.98 : P6/mmm, a=17.469(1), c=10.6409(7) A, Z=30, V=2813.5(8) A 3 ), while BaLi 1.06 In 1.16 has a rhombohedral structure (R-3c, a=18.894(3), c=85.289(17) A, Z=276, V=26368(8) A 3 ). BaLi 2.1 In 1.9 is isostructural with the known phase BaLi 4 . The phase BaLi 1.12 In 0.98 is structurally related to Na 8 K 23 Cd 12 In 48 , while BaLi 1.06 In 1.16 is isostructural with Li 33.3 Ba 13.1 Ca 3 . A sample containing structurally similar BaLi 1.12 In 0.98 and BaLi 1.02 In 1.16 was also investigated by transmission electron microscopy. Li 35 In 45 Ba 39 N 9 and LiIn 2 Ba 3 N 0.83 crystallize with tetragonal (I-42m, a=15.299(2), c=30.682(6) A, Z=2, V=7182(2) A 3 ) and cubic (Fd-3m, a=14.913(2) A, Z=8, V=3316.7(7) A 3 ) symmetry, respectively. While the first-mentioned subnitride belongs to the Li 80 Ba 39 N 9 structure type, the second extends the structural family of Ba 6 In 4.78 N 2.72 . The structural features of the new compounds are discussed in comparison to the known phases and the results of total energy calculations. - Graphical abstract: One-dimensional chain of face-sharing centered icosahedra in BaLi 2.1 In 1.9

  2. High-Temperature Superconductivity in Doped BaFe2As2

    International Nuclear Information System (INIS)

    Martin, Marianne

    2011-01-01

    This thesis provides a detailed look on the synthesis, structural features and physical properties of iron arsenides. Especially the properties of BaFe 2 As 2 and the solid solutions (Ba 1-x K x )Fe 2 As 2 , (Ba 1-x Sr x )Fe 2 As 2 and BaFe 2 (As 1-x P x ) 2 which were all synthesized by solid state reactions by heating mixtures of the elements, were intensively investigated.

  3. Superconductivity in gallium-substituted Ba8Si46 clathrates

    Science.gov (United States)

    Li, Yang; Zhang, Ruihong; Liu, Yang; Chen, Ning; Luo, Z. P.; Ma, Xingqiao; Cao, Guohui; Feng, Z. S.; Hu, Chia-Ren; Ross, Joseph H., Jr.

    2007-02-01

    We report a joint experimental and theoretical investigation of superconductivity in Ga-substituted type-I silicon clathrates. We prepared samples of the general formula Ba8Si46-xGax , with different values of x . We show that Ba8Si40Ga6 is a bulk superconductor, with an onset at TC≈3.3K . For x=10 and higher, no superconductivity was observed down to T=1.8K . This represents a strong suppression of superconductivity with increasing Ga content, compared to Ba8Si46 with TC≈8K . Suppression of superconductivity can be attributed primarily to a decrease in the density of states at the Fermi level, caused by a reduced integrity of the sp3 -hybridized networks as well as the lowering of carrier concentration. These results are corroborated by first-principles calculations, which show that Ga substitution results in a large decrease of the electronic density of states at the Fermi level, which explains the decreased superconducting critical temperature within the BCS framework. To further characterize the superconducting state, we carried out magnetic measurements showing Ba8Si40Ga6 to be a type-II superconductor. The critical magnetic fields were measured to be HC1≈35Oe and HC2≈8.5kOe . We deduce the London penetration depth λ≈3700Å and the coherence length ξc≈200Å . Our estimate of the electron-phonon coupling reveals that Ba8Si40Ga6 is a moderate phonon-mediated BCS superconductor.

  4. Crystallization of the HigBA2 toxin-antitoxin complex from Vibrio cholerae

    DEFF Research Database (Denmark)

    Hadǽi, San; Garcia-Pino, Abel; Martinez-Rodriguez, Sergio

    2013-01-01

    The genome of Vibrio cholerae encodes two higBA toxin-antitoxin (TA) modules that are activated by amino-acid starvation. Here, the TA complex of the second module, higBA2, as well as the C-terminal domain of the corresponding HigA2 antitoxin, have been purified and crystallized. The HigBA2 compl...

  5. Effect of Barium-Precursors on Reaction Kinetics in Y-Ba-Cu-O System

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The reactions of stoichiometric Y2O3, CuO, and different Ba salts or oxides (BaCO3, Ba(NO3)2, BaO2, BaCuO2) for forming various compounds in the Y-Ba-Cu-O system (i.e., YBa2Cu3O7-δ, BaCuO2, Y2BaCuO5 and Y2Cu2O5) were systematically investigated by thermal analysis and X-ray diffractometry. The relevant activation energies were calculated from thermogravimetric data. It is found that the reaction pathway significantly depends on the thermal stability of the Ba precursors. Binary BaO-CuO phases form at low temperature (650~700 ℃) when in presence of easy-to-decompose Ba precursors, and then slowly transform to ternary compounds. On the contrary, when Ba ions are released at temperature higher than 900 ℃, ternary phases form directly from the components.

  6. 40 CFR 721.10010 - Barium manganese oxide (BaMnO3).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Barium manganese oxide (BaMnO3). 721... Substances § 721.10010 Barium manganese oxide (BaMnO3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as barium manganese oxide (BaMnO3) (PMN P-00...

  7. First-principles study of (Ba ,Ca ) TiO3 and Ba (Ti ,Zr ) O3 solid solutions

    Science.gov (United States)

    Amoroso, Danila; Cano, Andrés; Ghosez, Philippe

    2018-05-01

    (Ba ,Ca ) TiO3 and Ba (Ti ,Zr ) O3 solid solutions are the building blocks of lead-free piezoelectric materials that attract a renewed interest. We investigate the properties of these systems by means of first-principles calculations, with a focus on the lattice dynamics and the competition between different ferroelectric phases. We first analyze the four parent compounds in order to compare their properties and their different tendency towards ferroelectricity. The core of our study is systematic characterization of the binary systems (Ba ,Ca ) TiO3 and Ba (Ti ,Zr ) O3 within both the virtual crystal approximation and direct supercell calculations. In the case of Ca doping, we find a gradual transformation from B -site to A -site ferroelectricity due to steric effects that largely determines the behavior of the system. In the case of Zr doping, in contrast, the behavior is eventually dominated by cooperative Zr-Ti motions and the local electrostatics. In addition, our comparative study reveals that the specific microscopic physics of these solids sets severe limits to the applicability of the virtual crystal approximation for these systems.

  8. Optical characteristics of BaGa2S4:Ho3+ and BaGa2Se4:Ho3+ single crystals

    International Nuclear Information System (INIS)

    Choe, Sung-Hyu; Jin, Moon-Seog; Kim, Wha-Tek

    2005-01-01

    BaGa 2 S 4 , BaGa 2 S 4 :Ho 3+ , BaGa 2 Se 4 , and BaGa 2 Se 4 :Ho 3+ single crystals were grown by using the chemical transport reaction method. The optical energy gaps of the single crystals were investigated in the temperature region from 11 K to 300 K. The temperature dependence of the optical energy gap was well fitted by the Varshni equation. Two broad emission bands were observed in the photoluminescence spectra of the single crystals. These bands were attributed to donor-acceptor pair recombinations. Sharp emission peaks were observed in the BaGa 2 S 4 :Ho 3+ and the BaGa 2 Se 4 :Ho 3+ single crystals and were assigned to radiation recombination between split Stark levels of Ho 3+ .

  9. Stellar Laboratories: 3. New Ba 5, Ba 6, and Ba 7 Oscillator Strengths and the Barium Abundance in the Hot White Dwarfs G191-B2B and RE 0503-289

    Science.gov (United States)

    Rauch, T.; Werner, K.; Quinet, P.; Kruk, Jeffrey Walter

    2014-01-01

    Context. For the spectral analysis of high-resolution and high-signal-to-noise (S/N) spectra of hot stars, state-of-the-art non-local thermodynamic equilibrium (NLTE) model atmospheres are mandatory. These are strongly dependent on the reliability of the atomic data that is used for their calculation. Aims. Reliable Ba 5-7 oscillator strengths are used to identify Ba lines in the spectra of the DA-type white dwarf G191-B2B and the DO-type white dwarf RE 0503-289 and to determine their photospheric Ba abundances. Methods. We newly calculated Ba v-vii oscillator strengths to consider their radiative and collisional bound-bound transitions in detail in our NLTE stellar-atmosphere models for the analysis of Ba lines exhibited in high-resolution and high-S/N UV observations of G191-B2B and RE 0503-289. Results. For the first time, we identified highly ionized Ba in the spectra of hot white dwarfs. We detected Ba vi and Ba vii lines in the Far Ultraviolet Spectroscopic Explorer (FUSE) spectrum of RE 0503-289. The Ba vi/Ba vii ionization equilibrium is well reproduced with the previously determined effective temperature of 70 000 K and surface gravity of log g=7.5. The Ba abundance is 3.5 +/- 0.5 × 10(exp-4) (mass fraction, about 23 000 times the solar value). In the FUSE spectrum of G191-B2B, we identified the strongest Ba vii line (at 993.41 Å) only, and determined a Ba abundance of 4.0 +/- 0.5 × 10(exp-6) (about 265 times solar). Conclusions. Reliable measurements and calculations of atomic data are a pre-requisite for stellar-atmosphere modeling. Observed Ba vi-vii line profiles in two white dwarfs' (G191-B2B and RE 0503-289) far-ultraviolet spectra were well reproduced with our newly calculated oscillator strengths. This allowed to determine the photospheric Ba abundance of these two stars precisely.

  10. Syntheses, crystal structures and characterizations of BaZn(SeO3)2 and BaZn(TeO3)Cl2

    International Nuclear Information System (INIS)

    Jiang Hailong; Feng Meiling; Mao Jianggao

    2006-01-01

    Two new barium zinc selenite and tellurite, namely, BaZn(SeO 3 ) 2 and BaZn(TeO 3 )Cl 2 , have been synthesized by the solid state reaction. The structure of BaZn(SeO 3 ) 2 features double chains of [Zn(SeO 3 ) 2 ] 2- anions composed of four- and eight-member rings which are alternatively along a-axis. The double chains of [Zn 2 (TeO 3 ) 2 Cl 3 ] 3- anions in BaZn(TeO 3 )Cl 2 are formed by Zn 3 Te 3 rings in which each tellurite group connects with three ZnO 3 Cl tetrahedra. BaZn(SeO 3 ) 2 and BaZn(TeO 3 )Cl 2 are wide bandgap semiconductors based on optical diffuse reflectance spectrum measurements. -- Graphical abstract: Two new barium zinc selenite and tellurite, namely, BaZn(SeO 3 ) 2 and BaZn(TeO 3 )Cl 2 , have been synthesized by solid state reaction. The structure of BaZn(SeO 3 ) 2 features 1D double chains of [Zn(SeO 3 ) 2 ] 2- anions composed of four- and eight-member rings which are alternatively along a-axis. The 1D double chains of [Zn 2 (TeO 3 ) 2 Cl 3 ] 3- anions in BaZn(TeO 3 )Cl 2 are formed by Zn 3 Te 3 rings in which each tellurite group connects with one ZnO 3 Cl and two ZnO 2 Cl 2 tetrahedra. BaZn(SeO 3 ) 2 and BaZn(TeO 3 )Cl 2 are wide bandgap semiconductors based on optical diffuse reflectance spectrum measurements

  11. Experimental investigation of decay properties of neutron deficient $^{116-118}$Ba isotopes and test of $^{112-115}$Ba beam counts

    CERN Multimedia

    We propose to study decay of neutron deficient isotopes $^{116-118}$Ba using Double Sided Silicon Strip Detector (DSSSD). To study delayed-proton and $\\alpha$-decay branching ratios of $^{116-118}$Ba are of special interest because of their vicinity to the proton drip line. The nuclear life-times and properties of the proton unstable states of Cs isotopes, populated through decay of $^{116-118}$Ba isotopes will be measured. In addition to that we propose beam development of $^{112-115}$Ba to study exotic decay properties of these neutron deficient nuclei and to search for super-allowed $\\alpha$-decay in future.

  12. Stellar neutron capture cross sections of the Ba isotopes

    International Nuclear Information System (INIS)

    Voss, F.; Wisshak, K.; Guber, K.; Kaeppeler, F.; Reffo, G.

    1994-03-01

    The neutron capture cross sections of 134 Ba, 135 Ba, 136 Ba, and 137 Ba were measured in the energy range from 5 to 225 keV at the Karlsruhe 3.75 MV Van de Graaff accelerator. Neutrons were produced via the 7 Li(p,n) 7 Be reaction by bombarding metallic Li targets with a pulsed proton beam. Capture events were registered with the Karlsruhe 4π Barium Fluoride Detector. Several runs have been performed under different experimental conditions to study the systematic uncertainties, which resulted mainly from the large ratios of total to capture cross sections of up to 400. The cross section ratios were determined with an overall uncertainty of ∼3%, an improvement by factors of five to eight compared to existing data. Severe discrepancies were found with respect to previous results. Maxwellian averaged neutron capture cross sections were calculated for thermal energies between kT=10 keV and 100 keV. These stellar cross sections were used in an s-process analysis. For the s-only isotopes 134 Ba and 136 Ba the N s ratio was determined to 0.875±0.025. Hence, a significant branching of the s-process path at 134 Cs can be claimed for the first time, in contrast to predictions from the classical approach. This branching yields information on the s-process temperature, indicating values around T 8 =2. The new cross sections are also important for the interpretation of barium isotopic anomalies, which were recently discovered in SiC grains of carbonaceous chondrite meteorites. Together with the results from previous experiments on tellurium and samarium, a general improvement of the N s systematics in the mass range A=120 to 150 is achieved. This allows for a more reliable separation of s- and r-process yields, resulting in an improved assignment of the respective contributions to elemental barium that is required for comparison with stellar observations. (orig.) [de

  13. Influence of Impurities on the Luminescence of Er3+ Doped BaTiO3 Nanophosphors

    Directory of Open Access Journals (Sweden)

    G. D. Webler

    2014-01-01

    Full Text Available The influence of the presence of barium carbonate (BaCO3 phase on the luminescence properties of barium titanate nanocrystals (BaTiO3 powders was investigated. Structural and optical characterizations of erbium (Er3+ doped BaTiO3 synthesized by the sol-emulsion-gel were performed. Using Fourier transform infrared spectroscopy and X-ray powder diffraction, we identified the presence of impurities related to BaCO3 and quantified its fraction. It was observed that the presence of BaCO3 phase, even at low levels, depletes significantly the infrared-to-visible upconverted luminescence efficiency of the produced nanopowders.

  14. Effects of Ce, La and Ba addition on the electrochemical behavior of super duplex stainless steels

    International Nuclear Information System (INIS)

    Yoo, Yun-Ha; Choi, Yoon-Seok; Kim, Jung-Gu; Park, Yong-Soo

    2010-01-01

    The effects of rare earth metal (REM: Ce, La) and Ba addition on aqueous corrosion properties of super duplex stainless steels (SDSS) were investigated by electrochemical tests and surface analyses. The results of potentiodynamic test indicated that the passive range increased by the addition of Ce, La, and Ba, indicating increased relative resistance to localized corrosion. The EIS measurements showed that the Ce-La-Ba-bearing alloys exhibited higher R ct and R p values than the Ce-La-Ba-free alloy at the passive and breakdown states. Furthermore, the additions of REMs and Ba together promoted the formation of dense chromium-enriched passive film.

  15. Synthesis and characterization of BaTiO3 ferroelectric material

    International Nuclear Information System (INIS)

    Osman, K.I.

    2011-01-01

    BaTiO 3 powder was prepared at low temperatures using the solid-state reaction, starting with two different precursors; the BaCO 3 /TiO 2 and the Ba(NO 3 ) 2 /TiO 2 powder mixtures. It was found that, a single phase BaTiO 3 was formed after calcination at 750 degree C for 10 h and at 600 degree C for 6 h for the first and second mixtures, respectively. Thermal and XRD analyses were used to study the formation kinetics of BaTiO 3 . Contracting volume reaction model was found to control both reactions. The SEM of the as milled powder, TMA, TG and thermodynamics analysis have been used to propose a realistic approach describing the reaction mechanism of BaTiO 3 . Characterization and the dielectric properties of the sintered BaTiO 3 were investigated. The relative permittivity and the dielectric loss measured at room temperature and at 1 khz were 2028.5 and 0.043 for BaTiO 3 prepared from BaCO 3 /TiO 2 , while they were 1805.33 and 0.41 for BaTiO 3 prepared from Ba(NO 3 ) 2 /TiO 2 .

  16. Luminescent properties of BaCl2-Eu microcrystals embedded in a CsI matrix

    International Nuclear Information System (INIS)

    Pushak, A.; Vistovskyy, V.; Voloshinovskii, A.; Savchyn, P.; Antonyak, O.; Demkiv, T.; Dacyuk, Yu.; Myagkota, S.; Gektin, A.

    2013-01-01

    The spectral-luminescent properties of CsI-BaCl 2 (1 mol%)-Eu(0.02 mol%) crystalline system are studied. Europium ion doped BaCl 2 microcrystals embedded in a CsI matrix are revealed on CsI-BaCl 2 (1 mol%)-Eu(0.02 mol%) freshly cleaved surface by the scanning electron microscopy. The size of microcrystals is shown to be within 0.5–5 microns. The luminescent parameters of the BaCl 2 -Eu 2+ microcrystals are shown to be similar to ones of a single crystal analogue. The 4f → 5d absorption transitions in europium ions and the reabsorption of the intrinsic emission of the CsI host are the main excitation mechanisms of europium luminescence in the BaCl 2 microcrystals. -- Highlights: ► The formation of chloride BaCl 2 :Eu microcrystals in the case of BaCl 2 doped CsI crystal has been revealed. ► The observed size of microcrystals at BaCl 2 concentration of 1% is about 0.5–5 μm. ► Majority of Eu 2+ ions in CsI-BaCl 2 -EuCl 3 crystalline system enters into BaCl 2 microcrystals. ► The luminescent parameters of the BaCl 2 :Eu 2+ microcrystals and its bulk analogue are similar

  17. Effect of lithium doping in BaTiO3 ceramics for vibration sensor application

    Science.gov (United States)

    Praveen, E.; Murugan, S.; Jayakumar, K.

    2018-04-01

    Phase pure undoped and Lithium doped BaTiO3 particles have been synthesized by high temperature solid-state reaction method. Substitution of Lithium at the Ba2+ site in BaTiO3 lattice has been investigated. The structural, vibrational, electrical and mechanical characterization have been carried out. The poled samples were used as a sensing element for the detection of mechanical oscillations and the presence of 80 Hz pulse in the output spectrum manifest the response of the sensor element to the applied mechanical stress. In comparison with pure BaTiO3 the sensitivity of Li doped BaTiO3 is 14 times greater than the pure BaTiO3. This confirms that Li doped BaTiO3 could be an efficient candidate for the functionalization of vibration sensors in space application.

  18. Growth of BaTiO3-PVDF composite thick films by using aerosol deposition

    Science.gov (United States)

    Cho, Sung Hwan; Yoon, Young Joon

    2016-01-01

    Barium titanate (BaTiO3)-polyvinylidene fluoride (PVDF) composite thick films were grown by using aerosol deposition at room temperature with BaTiO3 and PVDF powders. To produce a uniform composition in ceramic and polymer composite films, which show a substantial difference in specific gravity, we used PVDF-coated BaTiO3 powders as the starting materials. An examination of the microstructure confirmed that the BaTiO3 were well distributed in the PVDF matrix in the form of a 0 - 3 compound. The crystallite size in the BaTiO3-PVDF composite thick films was 5 ˜ 50 times higher than that in pure BaTiO3 thick films. PVDF plays a role in suppressing the fragmentation of BaTiO3 powder during the aerosol deposition process and in controlling the relative permittivity.

  19. Performances of RPCs in the BaBar Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Messner, Robert

    2003-09-26

    The BaBar experiment uses a big system based on RPC detectors to discriminate muons from pions and to identify neutral hadrons. About 2000 m{sup 2} of RPC chambers have been working at SLAC since the end of 1998. We report on the performances of the RPC chambers focusing on new problems discovered in the RPC behavior. These problems started very soon after the installation of the chambers on the detector when the high ambient temperature triggered an increase of dark currents inside the chambers and a reduction of the efficiency. Careful analysis of the BaBar data and dedicated R&D efforts in the laboratory have helped to identify the main source of the trouble in the linseed oil varnish on the bakelite electrodes.

  20. AMiBA: BROADBAND HETERODYNE COSMIC MICROWAVE BACKGROUND INTERFEROMETRY

    International Nuclear Information System (INIS)

    Chen, M.-T.; Li, C.-T.; Hwang, Y.-J.; Jiang Homin; Altamirano, Pablo; Chang, C.-H.; Chang, S.-H.; Chang, S.-W.; Han, C.-C.; Huang, Y.-D.; Kubo, Derek; Martin-Cocher, Pierre; Oshiro, Peter; Raffin, Philippe; Wei Tashun; Chiueh, T.-D.; Chu, T.-H.; Wang Huei; Kesteven, Michael; Wilson, Warwick

    2009-01-01

    The Y. T. Lee Array for Microwave Background (AMiBA) has reported the first results on the detection of galaxy clusters via the Sunyaev-Zel'dovich effect. The objectives required small reflectors in order to sample large-scale structures (20'), while interferometry provided modest resolutions (2'). With these constraints, we designed for the best sensitivity by utilizing the maximum possible continuum bandwidth matched to the atmospheric window at 86-102 GHz, with dual polarizations. A novel wide-band analog correlator was designed that is easily expandable for more interferometer elements. Monolithic millimeter-wave integrated circuit technology was used throughout as much as possible in order to miniaturize the components and to enhance mass production. These designs will find application in other upcoming astronomy projects. AMiBA is now in operation since 2006, and we are in the process to expand the array from seven to 13 elements.

  1. DIRC - a particle identification system for BaBar

    International Nuclear Information System (INIS)

    Hoecker, A.

    1999-10-01

    The DIRC (an acronym for Detection of Internally Reflected Cherenkov light) is a novel type of Cherenkov imaging device that has been developed, built and installed as part of the BaBar detector at the asymmetric B-factory PEP-II at SLAC. The DIRC is based on total internal reflection of Cherenkov photons produced and guided within thin, rectangular quartz bars covering the barrel region of BaBar. The photon detector is an array of photomultiplier tubes covering the photon phase space at the backward end of the bars. In its first few months of operation the DIRC performance has been found to achieve the design requirements. This note presents results from cosmic ray data and an analysis of the first beam collision runs. (author)

  2. Configuration Database for BaBar On-line

    International Nuclear Information System (INIS)

    Salnikov, Andrei

    2003-01-01

    The configuration database is one of the vital systems in the BaBar on-line system. It provides services for the different parts of the data acquisition system and control system, which require run-time parameters. The original design and implementation of the configuration database played a significant role in the successful BaBar operations since the beginning of experiment. Recent additions to the design of the configuration database provide better means for the management of data and add new tools to simplify main configuration tasks. We describe the design of the configuration database, its implementation with the Objectivity/DB object-oriented database, and our experience collected during the years of operation

  3. Dynamic moments of inertia in Xe, Cs and Ba nuclei

    International Nuclear Information System (INIS)

    El-Samman, H.; Barci, V.; Gizon, A.

    1984-01-01

    The γ-rays following the reactions induced by 12 C ions on 115 In, 112 , 117 , 122 Sn and 123 Sb targets have been investigated using six NaI(Tl) detectors in a two-dimensional arrangement. The collective moment of inertia I( 2 ) /sub band/ of 118 , 122 Xe, 123 Cs and 128 , 130 Ba have been extracted from the energy-correlation spectra. The behaviour of these nuclei and the observed differences are interpreted in terms of high-spin collective properties. Data are also presented on the effective moment of inertia I( 2 )/sub eff/ of 118 Xe and 130 Ba measured by sum-spectrometer techniques. 13 references

  4. Dynamic Displacement Disorder of Cubic BaTiO3

    Science.gov (United States)

    Paściak, M.; Welberry, T. R.; Kulda, J.; Leoni, S.; Hlinka, J.

    2018-04-01

    The three-dimensional distribution of the x-ray diffuse scattering intensity of BaTiO3 has been recorded in a synchrotron experiment and simultaneously computed using molecular dynamics simulations of a shell model. Together, these have allowed the details of the disorder in paraelectric BaTiO3 to be clarified. The narrow sheets of diffuse scattering, related to the famous anisotropic longitudinal correlations of Ti ions, are shown to be caused by the overdamped anharmonic soft phonon branch. This finding demonstrates that the occurrence of narrow sheets of diffuse scattering agrees with a displacive picture of the cubic phase of this textbook ferroelectric material. The presented methodology allows one to go beyond the harmonic approximation in the analysis of phonons and phonon-related scattering.

  5. Extended analysis of six-times ionized barium (Ba VII)

    International Nuclear Information System (INIS)

    Sharma, M.K.; Tauheed, A.; Rahimullah, K.

    2013-01-01

    The seventh spectrum of barium (Ba VII) has been investigated using experimental recordings made on a 3-m normal incidence vacuum spectrograph in Canada in the wavelength region 300–2000 Å. The data below 350 Å was supplemented from the spectrograms recorded on a 10.7-m grazing incidence spectrograph of NIST laboratory USA. The sources used to excite the spectra in both the cases were triggered spark. Previously reported levels of 5s 2 5p 2 , 5s5p 3 , 5s 2 5p5d and 5s 2 5p6s in Ba VII have been confirmed except the 1 P 1 level of 5s 2 5p5d. The analysis has been extended considerably to include new configurations 5s 2 5p6d and 5s 2 5p7s in odd parity configuration and doubly excited configurations 5s 2 5p6p, 5s 2 5p4f, 5s 2 5p5f, 5p 4 , 5s5p 2 5d and 5s5p 2 6s in even parity configuration. The 3 F 4 level of 5s 2 5p5d configuration has now been established through the identification of transitions from 5s 2 5p6p. In all, one hundred twenty-two levels have been established in this spectrum out of which ninety-two are new. A configuration interaction Hartree–Fock calculation supports the analysis. -- Highlights: ► The spectrum of Ba was recorded on a 3-m spectrograph with triggered spark source. ► Atomic transitions for Ba VII were identified to established new energy levels. ► CI calculations with relativistic corrections were made for theoretical predictions. ► Weighted oscillator strength (gf) and transition probabilities (gA) were calculated

  6. Extended analysis of four-times ionized barium: (Ba V)

    International Nuclear Information System (INIS)

    Sharma, M.K.; Rahimullah, K.; Tauheed, A.

    2014-01-01

    The fifth spectrum of barium (Ba V) has been investigated with the aid of experimental recordings made on a 3-m normal incidence vacuum spectrograph at the Antigonish laboratory (Canada) in the wavelength region 300–2080 Å using triggered spark as an excitation source. The spectral analysis has been extended considerably to include new configuration 5s 2 5p 3 6p in even parity configuration and, 5s 2 5p 3 6d and 5s 2 5p 3 7s in odd parity configuration. Previously reported levels of the ground configuration and three lowest excited configurations 5s5p 5 , 5s 2 5p 3 5d and 5s 2 5p 3 6s in Ba V have been confirmed and all the J≥4 unknown levels of 5s 2 5p 3 5d configuration have now been established through the identification of transitions from the levels of 5s 2 5p 3 6p configuration. All the levels of 5s 2 5p 3 6p configuration and thirty seven out of forty eight levels of the 5s 2 5p 3 6d and 5s 2 5p 3 7s configurations have now been established. A configuration interaction Hartree–Fock calculation supports the analysis. -- Highlights: • The spectrum of Ba was recorded on a 3-m spectrograph with triggered spark source. • CI calculations with relativistic corrections were made for theoretical predictions. • Atomic transitions for Ba V were identified to established new energy levels. • Weighted oscillator strength (gf) and transition probabilities (gA) were calculated

  7. Standardization of 137 Cs+137m Ba by Liquid Scintillation

    International Nuclear Information System (INIS)

    Rodriguez, L.; Arcos, J.M., los; Grau Carles, A.

    1995-09-01

    A procedure for the preparation of a stable, homogeneous solution of ''137 Cs+''137m Ba, for use in liquid scintillation measurements, is described. Its count rate stability and spectral time evolution has been followed for several weeks. The solution has been standardised by the CIEMAT/NIST method in both Ultima-Gold and Insta-Gel, to a combined uncertainty lower than 0,51% (k=1)

  8. Interface control in BaTiO3 based supercapacitors

    Science.gov (United States)

    Maglione, Mario; Elissalde, Catherine; Chung, U.-Chan

    2010-03-01

    Core shell BaTiO3 based particles sintered using advanced processes provide a high control of grain boundaries in bulk composites. As a result, supercapacitor behavior was evidenced which came from the balance between inner grain conductivity and grain boundary dielectric barrier. Thanks to the core-shell structure of the starting particles, improved control of the effective dielectric parameters can be achieved.

  9. Crazy for Ya Ba: methamphetamine use among northern Thai youth.

    Science.gov (United States)

    Cohen, Anjalee

    2014-07-01

    Since the mid-1990s, Thailand has been one of the largest per capita consumers of methamphetamine pills (ya ba - "crazy drug") in the world and one of the leading consumers of methamphetamine in Southeast Asia, with its youth comprising the majority of users. This article examines the socio-cultural context of methamphetamine use among young Thai in order to understand its widespread appeal. The study is based on 18 months of ethnographic research in Chiang Mai, northern Thailand, between 2002 and 2006 and a follow-up field trip in 2011. In-depth interviews were carried out with 211 young people aged between 15 and 25 in institutional and non-institutional settings. Many of the findings derive from participant observation and informal interviews with a small sample of 20 people. Chiang Mai youth have transformed methamphetamine from a labourers' drug centred on economic utility to a multi-purpose youth drug primarily consumed for pleasure and performance. Ya ba appeals to many young Thai due to its positive image as a modern and fashionable consumer commodity, with confidence in these synthetic pills drawing on and mirroring a broader faith in modern (western) medicine. The growing demand for ya ba in northern Thailand is in part a reflection of the changing social values that have accompanied rapid urbanisation and modernisation in Thailand. In their overwhelming aspiration to be modern, young Thai are consuming ya ba not to rebel against the dominant culture, but to keep up with the demands and expectations of a modern capitalist society. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Systematics of triaxial deformation in Xe, Ba, and Ce nuclei

    International Nuclear Information System (INIS)

    Yan, J.; Vogel, O.; von Brentano, P.; Gelberg, A.

    1993-01-01

    The (β,γ) deformation parameters of even-even Xe, Ba, and Ce nuclei have been calculated by using the triaxial rotor model. Deformation parameters calculated, on one hand, from decay properties and, on the other hand, from energies are in good agreement. The smooth dependence of the deformation parameters on Z and N is discussed. The results are compared with those extracted from properties of odd-A nuclei

  11. Identical bands in Ba-Dy, N < 104 space

    International Nuclear Information System (INIS)

    Mittal, H.M.; Vidya Devi; Gupta, J.B.

    2008-01-01

    The recognition of the existence of identical bands, in even-even, odd-even and odd-odd nuclei, in normal deformed bands and superdeformed bands has become the subject of great interest in recent years. Here the search have been taken for such bands for the normal deformed, even-Z, even-N nuclei of Ba and Dy for 82< N<104 major shell space

  12. Ferromagnetic clusters in polycrystalline BaCoO3

    International Nuclear Information System (INIS)

    Botta, P.M.; Pardo, V.; Calle, C. de la; Baldomir, D.; Alonso, J.A.; Rivas, J.

    2007-01-01

    Polycrystalline BaCoO 3 was synthesized by a citrate technique using thermal treatments at high oxygen pressure. Magnetic susceptibility measurements on the compound were carried out under AC conditions. The magnetic properties of the material at low temperatures were found to be determined by the appearance of nanoscale ferromagnetic (FM) regions and not by a true magnetic phase transition. These clusters have a mean size of about 1 nm in diameter and obey an Arrhenius-like thermal relaxation

  13. From Ba3Ta5O14N to LaBa2Ta5O13N2: Decreasing the optical band gap of a photocatalyst

    International Nuclear Information System (INIS)

    Anke, B.; Bredow, T.; Pilarski, M.; Wark, M.; Lerch, M.

    2017-01-01

    Yellow LaBa 2 Ta 5 O 13 N 2 was successfully synthesized as phase-pure material crystallizing isostructurally to previously reported Ba 3 Ta 5 O 14 N and mixed-valence Ba 3 Ta V 4 Ta IV O 15 . The electronic structure of LaBa 2 Ta 5 O 13 N 2 was studied theoretically with the range-separated hybrid method HSE06. The most stable structure was obtained when lanthanum was placed on 2a and nitrogen on 4h sites confirming Pauling's second rule. By incorporating nitrogen, the measured band gap decreases from ∼3.8 eV for the oxide via 2.74 eV for Ba 3 Ta 5 O 14 N to 2.63 eV for the new oxide nitride, giving rise to an absorption band well in the visible-light region. Calculated fundamental band gaps confirm the experimental trend. The atom-projected density of states has large contributions from N2p orbitals close to the valence band edge. These are responsible for the observed band gap reduction. Photocatalytic hydrogen formation was investigated and compared with that of Ba 3 Ta 5 O 14 N revealing significantly higher activity for LaBa 2 Ta 5 O 13 N 2 under UV-light. - Graphical abstract: X-ray powder diffraction pattern of LaBa 2 Ta 5 O 13 N 2 with the results of the Rietveld refinements. Inset: Unit cell of LaBa 2 Ta 5 O 13 N 2 and polyhedral representation of the crystal structure. - Highlights: • Synthesis of a new oxide nitride LaBa 2 Ta 5 O 13 N 2 . • Refinement of the crystal structure. • Quantum chemical calculations provided band gap close to the measured value. • New phase shows a higher photocatalytic H 2 evolution rate compared to prior tested Ba 3 Ta 5 O 14 N.

  14. Ultrasonic investigations on polonides of Ba, Ca, and Pb

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Devraj; Bhalla, Vyoma [Amity School of Engineering and Technology, New Delhi (India). Dept. of Applied Physics; Bala, Jyoti [Amity School of Engineering and Technology, New Delhi (India). Dept. of Applied Physics; Guru Gobind Singh Indraprastha Univ., New Delhi (India). USICT; Wadhwa, Shikha [Amity Univ., Noida (India). Amity Inst. of Nanotechnology

    2017-07-01

    The temperature-dependent mechanical and ultrasonic properties of barium, calcium, and lead polonides (BaPo, CaPo, and PbPo) were investigated in the temperature range 100-300 K. The second- and third-order elastic constants (SOECs and TOECs) were computed using Coulomb and Born-Mayer potential and these in turn have been used to estimate other secondary elastic properties such as strength, anisotropy, microhardness, etc. The theoretical approach followed the prediction that BaPo, CaPo, and PbPo are brittle in nature. PbPo is found to be the hardest amongst the chosen compounds. Further the SOECs and TOECs are applied to determine ultrasonic velocities, Debye temperature, and acoustic coupling constants along left angle 100 right angle, left angle 110 right angle, and left angle 111 right angle orientations at room temperature. Additionally thermal conductivity has been computed using Morelli and Slack's approach along different crystallographic directions at room temperature. Finally ultrasonic attenuation due to phonon-phonon interaction and thermoelastic relaxation mechanisms has been computed for BaPo, CaPo, and PbPo. The behaviour of these compounds is similar to that of semi-metals with thermal relaxation time of the order 10{sup -11} s. The present computation study is reasonably in agreement with the available theoretical data for the similar type of materials.

  15. Synthesis and characterization of (Ba,Yb doped ceria nanopowders

    Directory of Open Access Journals (Sweden)

    Branko Matović

    2011-06-01

    Full Text Available Nanometric size (Ba, Yb doped ceria powders with fluorite-type structure were obtained by applying selfpropagating room temperature methods. Tailored composition was: Ce0.95−xBa0.05YbxO2−δ with fixed amount of Ba − 0.05 and varying Yb content “x” from 0.05 to 0.2. Powder properties such as crystallite and particle size and lattice parameters have been studied. Röntgen diffraction analyses (XRD were used to characterize the samples at room temperature. Also, high temperature treatment (up to 1550°C was used to follow stability of solid solutions. The mean diameters of the nanocrystals are determined from the full width at half maxima (FWHM of the XRD peaks. It was found that average diameter of crystallites is less than 3 nm. WilliamsonHall plots were used to separate the effect of the size and strain in the nanocrystals.

  16. Computational study of Ca, Sr and Ba under pressure

    International Nuclear Information System (INIS)

    Jona, F; Marcus, P M

    2006-01-01

    A first-principles procedure for the calculation of equilibrium properties of crystals under hydrostatic pressure is applied to Ca, Sr and Ba. The procedure is based on minimizing the Gibbs free energy G (at zero temperature) with respect to the structure at a given pressure p, and hence does not require the equation of state to fix the pressure. The calculated lattice constants of Ca, Sr and Ba are shown to be generally closer to measured values than previous calculations using other procedures. In particular for Ba, where careful and extensive pressure data are available, the calculated lattice parameters fit measurements to about 1% in three different phases, both cubic and hexagonal. Rigid-lattice transition pressures between phases which come directly from the crossing of G(p) curves are not close to measured transition pressures. One reason is the need to include zero-point energy (ZPE) of vibration in G. The ZPE of cubic phases is calculated with a generalized Debye approximation and applied to Ca and Sr, where it produces significant shifts in transition pressures. An extensive tabulation is given of structural parameters and elastic constants from the literature, including both theoretical and experimental results

  17. Computational study of Ca, Sr and Ba under pressure

    Energy Technology Data Exchange (ETDEWEB)

    Jona, F; Marcus, P M [Department of Materials Science and Engineering, State University of New York, Stony Brook, NY 11794-2275 (United States)

    2006-05-17

    A first-principles procedure for the calculation of equilibrium properties of crystals under hydrostatic pressure is applied to Ca, Sr and Ba. The procedure is based on minimizing the Gibbs free energy G (at zero temperature) with respect to the structure at a given pressure p, and hence does not require the equation of state to fix the pressure. The calculated lattice constants of Ca, Sr and Ba are shown to be generally closer to measured values than previous calculations using other procedures. In particular for Ba, where careful and extensive pressure data are available, the calculated lattice parameters fit measurements to about 1% in three different phases, both cubic and hexagonal. Rigid-lattice transition pressures between phases which come directly from the crossing of G(p) curves are not close to measured transition pressures. One reason is the need to include zero-point energy (ZPE) of vibration in G. The ZPE of cubic phases is calculated with a generalized Debye approximation and applied to Ca and Sr, where it produces significant shifts in transition pressures. An extensive tabulation is given of structural parameters and elastic constants from the literature, including both theoretical and experimental results.

  18. The BaBar Software Architecture and Infrastructure

    International Nuclear Information System (INIS)

    Cosmo, Gabriele

    2003-01-01

    The BaBar experiment has in place since 1995 a software release system (SRT Software Release Tools) based on CVS (Concurrent Version System) which is in common for all the software developed for the experiment, online or offline, simulation or reconstruction. A software release is a snapshot of all BaBar code (online, offline, utilities, scripts, makefiles, etc.). This set of code is tested to work together, and is indexed by a release number (e.g., 6.8.2) so a user can refer to a particular release and get reproducible results. A release will involve particular versions of packages. A package generally consists of a set of code for a particular task, together with a GNU makefile, scripts and documentation. All BaBar software is maintained in AFS (Andrew File System) directories, so the code is accessible worldwide within the Collaboration. The combination SRT, CVS, AFS, has demonstrated to be a valid, powerful and efficient way of organizing the software infrastructure of a modern HEP experiment with collaborating Institutes distributed worldwide, both in a development and production phase

  19. Cesium immobilization in (Ba,Cr)-hollandites: Effects on structure

    Science.gov (United States)

    Tumurugoti, Priyatham; Sundaram, S. K.; Misture, Scott T.

    2018-02-01

    Hollandites with compositions Ba1.15-xCs2xCr2.3Ti5.7O16 (0 ≤ x ≤ 1.15) intended for the immobilization of cesium (Cs) from nuclear waste have been prepared, characterized, and analyzed for Cs retention properties. Sol-gel synthesized powders were used for structural characterization using a combination of X-ray, neutron, and electron diffraction techniques. Phase-pure hollandites adopting tetragonal (I4/m) or monoclinic symmetry (I2/m) were observed to form in the compositional range 0 ≤ x ≤ 0.4. Structural models for the compositions, x = 0, 0.15, and 0.25 were developed from Rietveld analysis of powder diffraction data. Refined anisotropic displacement parameters (βij) for the Ba and Cs ions in the hollandite tunnels indicate local disorder of Ba/Cs along the tunnel direction. In addition, weak superlattice reflections were observed in X-ray and electron diffraction patterns that were due to the compositional modulation i.e., ordering of ions and vacancies along tunnel direction. Our overall observations suggest the phase-pure hollandites studied assumed supercell structures with ordered tunnel cations, which in turn have positional disorder in individual supercells.

  20. Ultrasonic Investigations on Polonides of Ba, Ca, and Pb

    Science.gov (United States)

    Singh, Devraj; Bhalla, Vyoma; Bala, Jyoti; Wadhwa, Shikha

    2017-10-01

    The temperature-dependent mechanical and ultrasonic properties of barium, calcium, and lead polonides (BaPo, CaPo, and PbPo) were investigated in the temperature range 100-300 K. The second- and third-order elastic constants (SOECs and TOECs) were computed using Coulomb and Born-Mayer potential and these in turn have been used to estimate other secondary elastic properties such as strength, anisotropy, microhardness, etc. The theoretical approach followed the prediction that BaPo, CaPo, and PbPo are brittle in nature. PbPo is found to be the hardest amongst the chosen compounds. Further the SOECs and TOECs are applied to determine ultrasonic velocities, Debye temperature, and acoustic coupling constants along , , and orientations at room temperature. Additionally thermal conductivity has been computed using Morelli and Slack's approach along different crystallographic directions at room temperature. Finally ultrasonic attenuation due to phonon-phonon interaction and thermoelastic relaxation mechanisms has been computed for BaPo, CaPo, and PbPo. The behaviour of these compounds is similar to that of semi-metals with thermal relaxation time of the order 10-11 s. The present computation study is reasonably in agreement with the available theoretical data for the similar type of materials.

  1. Electronic States of IC60BA and PC71BM

    International Nuclear Information System (INIS)

    Sheng Chun-Qi; Wang Peng; Shen Ying; Li Wen-Jie; Li Hong-Nian; Zhang Wen-Hua; Zhu Jun-Fa; Lai Guo-Qiao

    2013-01-01

    We investigate the electronic states of IC 60 BA and PC 71 BM using first-principles calculations and photoelectron spectroscopy (PES) measurements. The energy level structures for all possible isomers are reported and compared with those of C 60 , C 70 and PC 61 BM. The attachment of the side chains can raise the LUMO energies and decrease the HOMO-LUMO gaps, and thus helps to increase the power-conversion efficiency of bulk heterojunction solar cells. In the PES studies, we prepared IC 60 BA and PC 71 BM films on Si:H(111) substrates to construct adsorbate/substrate interfaces describable with the integer charge-transfer (ICT) model. Successful measurements then revealed that one of the most important material properties for an electron acceptor, the energy of the negative integer charge-transfer state (E ICT− ), is 4.31 eV below the vacuum level for PC 71 BM. The E ICT− of IC 60 BA is smaller than 4.14 eV

  2. Structural and thermodynamic characterization of the perovskite-related BA{sub 1+y}UO{sub 3+x} and (BA,SR){sub 1+y}UO{sub 3+x} phases

    Energy Technology Data Exchange (ETDEWEB)

    Cordfunke, E.H.P. [Netherlands Energy Research Foundation (ECN), Petten (Netherlands); Booij, A.S. [Netherlands Energy Research Foundation (ECN), Petten (Netherlands); Smit-Groen, V. [Netherlands Energy Research Foundation (ECN), Petten (Netherlands); Vlaanderen, P. van [Netherlands Energy Research Foundation (ECN), Petten (Netherlands); IJdo, D.J.W. [Rijksuniversiteit Leiden (Netherlands). Gorlaeus Labs.

    1996-11-01

    The perovskite-type BaUO{sub 3} structure has been investigated by X-ray and neutron diffraction. The Ba/U ratio, the (Ba, Sr)/U ratio, and the oxygen stoichiometry in Ba{sub 1+y}UO{sub 3+x} were varied, and the integral enthalpies of formation determined by solution calorimetry. In addition, equilibrium oxygen partial pressures were measured using a reversible EMF cell. The chemical defect mechanism is discussed, and it is shown that a continuous series BaUO{sub 3}-Ba{sub 1+y}UO{sub 3+x}-Ba{sub 3}UO{sub 6} exist in which uranium vacancies are gradually filled up with barium ions, whereas uranium is oxidized via the pentavalent to the hexavalent state in Ba{sub 3}UO{sub 6}(=Ba{sub 2}(Ba, U)O{sub 6}). (orig.).

  3. Synthesis and electrical properties of BaBiO3 and high resistivity BaTiO3–BaBiO3 ceramics

    Directory of Open Access Journals (Sweden)

    Nitish Kumar

    2016-12-01

    Full Text Available Ceramics of the composition BaBiO3 (BB were sintered in oxygen to obtain a single phase with monoclinic I2/m symmetry as suggested by high-resolution X-ray diffraction. X-ray photoelectron spectroscopy confirmed the presence of bismuth in two valence states — 3+ and 5+. Optical spectroscopy showed presence of a direct bandgap at ∼ 2.2eV and a possible indirect bandgap at ∼ 0.9eV. This combined with determination of the activation energy for conduction of 0.25eV, as obtained from ac impedance spectroscopy, suggested that a polaron-mediated conduction mechanism was prevalent in BB. The BB ceramics were crushed, mixed with BaTiO3 (BT, and sintered to obtain BT–BB solid solutions. All the ceramics had tetragonal symmetry and exhibited a normal ferroelectric-like dielectric response. Using ac impedance and optical spectroscopy, it was shown that resistivity values of BT–BB were orders of magnitude higher than BT or BB alone, indicating a change in the fundamental defect equilibrium conditions. A shift in the site occupancy of Bi to the A-site is proposed to be the mechanism for the increased electrical resistivity.

  4. Glass formation and physicochemical properties of glasses of Ba(PO3)2-LiRAlF6 (R=Mg, Ca, Sr, Ba) system

    International Nuclear Information System (INIS)

    Khalilev, V.D.; Chkhenkeli, G.D.; Vakhrameev, V.I.

    1987-01-01

    Glass formation regions, crystallizability, optical constants, thermal linear expansion coefficient and IR absorption spectra of glass are studied in Ba(PO) 3 ) 2 - LiRAlF 6 system where R=Mg, Ca, Sr, Ba. The carried out investigation confirms participation of introduced fluorides (as modified cryolites) in structural transformations manifested in increase of glass formation regions and nonlinear variations of properties

  5. Octupole correlations in neutron-rich {sup 143,145}Ba and a type of superdeformed band in {sup 145}Ba

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, S.J.; Wang, M.G.; Long, G.L.; Zhu, L.Y.; Gan, C.Y.; Yang, L.M.; Sakhaee, M.; Li, M.; Deng, J.K. [Physics Department, Tsinghua University, Beijing 100084, Peoples Republic of (China); Zhu, S.J.; Hamilton, J.H.; Ramayya, A.V.; Jones, E.F.; Hwang, J.K.; Zhang, X.Q.; Gore, P.M.; Peker, L.K.; Drafta, G.; Babu, B.R.; Deng, J.K.; Ginter, T.N.; Beyer, C.J.; Kormicki, J.; Ter-Akopian, G.M.; Daniel, A.V. [Physics Department, Vanderbilt University, Nashville, Tennessee 37235 (United States); Zhu, S.J.; Ter-Akopian, G.M.; Daniel, A.V. [Joint Institute for Heavy Ion Research, Oak Ridge, Tennessee 37831 (United States); Ma, W.C. [Physics Department, Mississippi State University, Mississippi 39762 (United States); Cole, J.D.; Aryaeinejad, R.; Drigert, M.W. [Idaho National Engineering Laboratory, Idaho Falls, Idaho 83415 (United States); Rasmussen, J.O.; Asztalos, S.; Lee, I.Y.; Macchiavelli, A.O.; Chu, S.Y.; Gregorich, K.E.; Mohar, M.F. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Ter-Akopian, G.M.; Daniel, A.V.; Oganessian, Y.T.; Kliman, J. [Flerov Laboratory for Nuclear Reactions, Joint Institute for Nuclear Research, Dubna (Russia); Donangelo, R. [Universidade Federal do Rio de Janeiro, Caixa Postal 68528, RG (Brazil); Stoyer, M.A.; Lougheed, R.W.; Moody, K.J.; Wild, J.F. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Prussin, S.G. [Nuclear Engineering Department, University of California at Berkeley, Berkeley, California 94720 (United States); Kliman, J. [Institute of Physics, SASc, Dubravskacesta 9, 84228 Bratislava (Slovakia); Griffin, H.C. [University of Michigan, Ann Arbor, Michigan 48104 (United States)

    1999-11-01

    High spin states in neutron-rich odd-{ital Z} {sup 143,145}Ba nuclei have been investigated from the study of prompt {gamma} rays in the spontaneous fission of {sup 252}Cf by using {gamma}-{gamma}- and {gamma}-{gamma}-{gamma}- coincidence techniques. Alternating parity bands are identified for the first time in {sup 145}Ba and extended in {sup 143}Ba. A new side band, with equal, constant dynamic, and kinetic moments of inertia equal to the rigid body value, as found in superdeformed bands, is discovered in {sup 145}Ba. Enhanced E1 transitions between the negative- and positive-parity bands in these nuclei give evidence for strong octupole deformation in {sup 143}Ba and in {sup 145}Ba. These collective bands show competition and coexistence between symmetric and asymmetric shapes in {sup 145}Ba. Evidence is found for crossing M1 and E1 transitions between the s=+i and s={minus}i doublets in {sup 143}Ba. {copyright} {ital 1999} {ital The American Physical Society}

  6. The study of the effect of Ba coverage through the accelerations lifetime of activated BaO/SrO cathodes

    International Nuclear Information System (INIS)

    Hashim, A.A.; Ray, A.K.; Hassan, A.K.; Barratt, D.S.

    2005-01-01

    A novel type of BaO/SrO oxide cathode with 5% addition of Ni powder by weight on a Ni cap containing an activating impurity was studied. The conductivity and the electron activation energy were studied as a function of temperature in the range of 300-1200 K after conversion and activation of the cathode at 1200 K for 1 h. The experimental results yield three values for the activation energy of 1.49, 2.23 and 3.3 eV, which are close to BaO band structure parameters with a small shift due to the effect of other oxide components and metallic fraction additions. The experiments furthermore confirm that the current density of the cathode was enhanced at high temperature range with the long operation. The conduction mechanisms observed a metallic conduction at low temperature after operation for several 100 h due to improvements in the Ba coverage layer on the grains of oxide layer. Additionally, there appears a qualified conduction stability of the current density J = 10-45 mA cm -2 at the acceleration temperature range of 1100-1150 K under the duty of low voltage. The low voltage duty V = 30 mV is focused on the conduction electrons faraway from the emission electrons

  7. High field-effect mobility at the (Sr,Ba)SnO{sub 3}/BaSnO{sub 3} interface

    Energy Technology Data Exchange (ETDEWEB)

    Fujiwara, Kohei, E-mail: kfujiwara@imr.tohoku.ac.jp; Nishihara, Kazuki; Shiogai, Junichi; Tsukazaki, Atsushi [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

    2016-08-15

    A perovskite oxide, BaSnO{sub 3}, has been classified as one of transparent conducting materials with high electron mobility, and its application for field-effect transistors has been the focus of recent research. Here we report transistor operation in BaSnO{sub 3}-based heterostructures with atomically smooth surfaces, fabricated on SrTiO{sub 3} substrates by the (Sr,Ba)SnO{sub 3} buffer technique. Indeed, modulation of band profiles at the channel interfaces with the insertion of wide bandgap (Sr,Ba)SnO{sub 3} as a barrier layer results in a significant improvement of field-effect mobility, implying effective carrier doping at the regulated heterointerface. These results provide an important step towards realization of high-performance BaSnO{sub 3}-based field-effect transistors.

  8. Synthesis, crystal structure and electrical properties of A-site cation ordered BaErMn2O5 and BaErMn2O6

    International Nuclear Information System (INIS)

    Świerczek, Konrad; Klimkowicz, Alicja; Zheng, Kun; Dabrowski, Bogdan

    2013-01-01

    In this paper, we report on a synthesis procedure, structural and electrical properties of BaErMn 2 O 5 and BaErMn 2 O 6 , A-site double perovskites having layered arrangement of Ba and Er cations. These materials belong to a family of BaLnMn 2 O 5+δ oxides, which up to now were successfully synthesized for Ln=Y and La–Ho lanthanides. Up to our knowledge, this is the first report on the successful synthesis of BaErMn 2 O 5 and BaErMn 2 O 6 , yielding>95 wt% of the considered compounds. Structural characterization of the materials is given at room temperature, together with in situ XRD studies, performed during oxidation of BaErMn 2 O 5 in air, at elevated temperatures up to 500 °C. A complex structural behavior was observed, with oxidation process of BaErMn 2 O 5 occurring at around 300 °C. The oxidized BaErMn 2 O 6 shows a structural phase transition at about 225 °C. Results of structural studies are supported by thermogravimetric measurements of the oxidation process, performed in air, as well as reduction process, preformed in 5 vol% of H 2 in Ar. Additionally, isothermal oxidation/reduction cycles were measured at 500 °C, showing interesting properties of BaErMn 2 O 5+δ , from a point of view of oxygen storage technology. Electrical conductivity of BaErMn 2 O 5 is of the order of 10 −4 S cm −1 at room temperature and shows activated character on temperature with activation energy E a =0.30(1) eV. Positive sign of Seebeck coefficient for this material indicates holes as dominant charge carriers. Oxidized BaErMn 2 O 6 possesses much higher electrical conductivity, almost 0.2 S cm −1 at room temperature. Additional, about 10-fold increase of electrical conductivity, occurring in the vicinity of 225 °C for this material, can be associated with phase transition from charge/orbital-ordered insulator COI(CE) to paramagnetic metal PM phase. The highest conductivity for BaErMn 2 O 6 was measured near 500 °C and is almost equal to 40 S cm −1 , while

  9. Submillimeter and microwave residual losses in epitaxial films of Y-Ba-Cu-O and Tl-Ca-Ba-Cu-O

    International Nuclear Information System (INIS)

    Miller, D.; Richards, P.L.; Eom, C.B.; Geballe, T.H.; Etemad, S.; Inam, A.; Venkatesan, T.; Martens, J.S.; Lee, W.Y.

    1992-12-01

    We have used a novel bolometric technique and a resonant technique to obtain accurate submillimeter and microwave residual loss data for epitaxial thin films of YBa 2 Cu 3 O 7 , Tl 2 Ca 2 Ba 2 Cu 3 O 10 and Tl 2 CaBa 2 Cu 2 O 8 . For all films we obtain good agreement between the submillimeter and microwave data, with the residual losses in both the Y-Ba-Cu-O and Tl-Ca-Ba-Cu-O films scaling approximately as frequency squared below ∼ 1 THz. We are able to fit the losses in the Y-Ba-Cu-O films to a two fluid and a weakly coupled grain model for the a-b planeconductivity, in good agreement with results from a Kramers-Kronig analysis of the loss data

  10. Genome Sequence of African Swine Fever Virus BA71, the Virulent Parental Strain of the Nonpathogenic and Tissue-Culture Adapted BA71V.

    Science.gov (United States)

    Rodríguez, Javier M; Moreno, Leticia Tais; Alejo, Alí; Lacasta, Anna; Rodríguez, Fernando; Salas, María L

    2015-01-01

    The strain BA71V has played a key role in African swine fever virus (ASFV) research. It was the first genome sequenced, and remains the only genome completely determined. A large part of the studies on the function of ASFV genes, viral transcription, replication, DNA repair and morphogenesis, has been performed using this model. This avirulent strain was obtained by adaptation to grow in Vero cells of the highly virulent BA71 strain. We report here the analysis of the genome sequence of BA71 in comparison with that of BA71V. They possess the smallest genomes for a virulent or an attenuated ASFV, and are essentially identical except for a relatively small number of changes. We discuss the possible contribution of these changes to virulence. Analysis of the BA71 sequence allowed us to identify new similarities among ASFV proteins, and with database proteins including two ASFV proteins that could function as a two-component signaling network.

  11. Virus, bakterier og toksiner som biologiske kampstoffer

    DEFF Research Database (Denmark)

    Hansen, J E

    1999-01-01

    or individuals have developed biological weapons for offensive use in war or terrorism. This article reviews the publically available literature, and clinical and therapeutic possibilities are described. The possibilities for protection of military and civilian groups are discussed and the need for a national......Biological weapons are an important part of the level of international threat. Technological development has made biological weapon production relatively simple and cheap, and although a UN convention from 1972 bans biological weapons, governments as well as non-governmental organisations...

  12. Selektion og spredning af antibiotikaresistente bakterier

    DEFF Research Database (Denmark)

    Kolmos, Hans Jørn Jepsen; Frimodt-møller, Niels

    2011-01-01

    and disinfectants. Therefore, abundant use of metals, e.g. copper and zinc for growth promotion in animals used for food, may also co-select for antibiotic resistance. The same applies to disinfectants, e.g. silver and chlorhexidine. Prudent use of antibiotics and these other agents is essential to control...

  13. Isolasi Bakteri Inti Es pada Kentang

    Directory of Open Access Journals (Sweden)

    Triwidodo Arwiyanto

    1996-09-01

    Full Text Available Frost injury is one of the limiting factors in potato production in Dieng (2000 m above sea level, Central Java. The damage caused by frost has been recorded since long time ago, however, there is no studies about this matter. The objective of the present study is to isolate ice nucleation active bacteria which reside epiphytically at the surface of potato leaves. Potato and several crop leaves were collected and the ice catalyst was detected from leaf-washing. The bacteria were isolated on Nutrien Agar and Nutrien Agar Glycerol medium. The result indicated that ice catalyst was detected from the leaf washing of potato (Solanum tuberosum L. and broad bean (Vicia faba L. but not from others.  The ice catalyst was not detected from the extract of surface soil, neither. The ice nucleation active bacteria were successfully isolated from potato leaf and were identical to Erwinia ananas in their bacteriological properties. Key words: ice nucleating-active bacteria, potato, frost

  14. Structural evolution of Ba8Ti3Nb4O24 from BaTiO3 using a series of Ba(Ti1−5xNb4x)O3 solid solutions

    International Nuclear Information System (INIS)

    Barrientos Hernández, F.R.; Lira Hernández, I.A.; Gómez Yáñez, C.; Arenas Flores, A.; Cabrera Sierra, R.; Pérez Labra, M.

    2014-01-01

    Highlights: • The evolution phase Ba 8 Ti 3 Nb 4 O 24 was obtained through the mechanism Ba(Ti 1-5x Nb 4x )O 3 . • Addition of niobium can accelerate grain growth of BaTiO 3 ceramics. • Ba 8 Ti 3 Nb 4 O 24 presents a dielectric loss of 0.0035 and permittivity value of 54.6. • Electrical measurements showed that Nb 5+ content drops Curie temperature. • Samples with x ⩾ 0.0625 shows an insulating behavior. -- Abstract: In this work, the structural evolution of hexagonal phase Ba 8 Ti 3 Nb 4 O 24 by adding Nb 2 O 5 to perovskite structure of BaTiO 3 was investigated. The compositions Ba(Ti 1-5x Nb 4x )O 3 ceramics, with 0.00025 ⩽ x ⩽ 0.125 were prepared by the conventional solid state route in air atmosphere, the powders precursors, BaTiO 3 , BaCO 3 and Nb 2 O 5 , were mixed in stoichiometric proportions and ground in a ball mill using alumina balls and acetone. The mixed powders were calcined at temperatures up to 1500 °C. The phase transformation of Ba 8 Ti 3 Nb 4 O 24 from BaTiO 3 was studied by DRX, Raman spectroscopy, SEM, electrical measurements (relative permittivity and P–E hysteresis loops); Rietveld’s refinement was used to structurally characterize the samples. For the devices obtained capacitance was measured at 1 kHz; with these values we calculated the relative permittivity. The samples show typical P–E hysteresis loops at room temperature accompanied by saturation polarization (Ps) and remnant polarization (Pr). The DRX and Rietveld’s refinement results show x ⩽ 0.01 has a ferroelectric behavior. When the doped level is increased x ⩾ 0.02, a peak displacement is observed, this is due to the phase transformation of tetragonal to cubic into the unit cell. Finally, with x = 0.125 the crystal structure transforms to the characteristic hexagonal phase Ba 8 Ti 3 Nb 4 O 24 which resonates at microwave frequencies

  15. The 226Ra-Ba relationship in the North Atlantic during GEOTRACES-GA01

    Science.gov (United States)

    Le Roy, Emilie; Sanial, Virginie; Charette, Matthew A.; van Beek, Pieter; Lacan, François; Jacquet, Stéphanie H. M.; Henderson, Paul B.; Souhaut, Marc; García-Ibáñez, Maribel I.; Jeandel, Catherine; Pérez, Fiz F.; Sarthou, Géraldine

    2018-05-01

    We report detailed sections of radium-226 (226Ra, T1/2 = 1602 years) activities and barium (Ba) concentrations determined in the North Atlantic (Portugal-Greenland-Canada) in the framework of the international GEOTRACES program (GA01 section - GEOVIDE project, May-July 2014). Dissolved 226Ra and Ba are strongly correlated along the section, a pattern that may reflect their similar chemical behavior. Because 226Ra and Ba have been widely used as tracers of water masses and ocean mixing, we investigated their behavior more thoroughly in this crucial region for thermohaline circulation, taking advantage of the contrasting biogeochemical patterns existing along the GA01 section. We used an optimum multiparameter (OMP) analysis to distinguish the relative importance of physical transport (water mass mixing) from nonconservative processes (sedimentary, river or hydrothermal inputs, uptake by particles and dissolved-particulate dynamics) on the 226Ra and Ba distributions in the North Atlantic. Results show that the measured 226Ra and Ba concentrations can be explained by conservative mixing for 58 and 65 % of the samples, respectively, notably at intermediate depth, away from the ocean interfaces. 226Ra and Ba can thus be considered conservative tracers of water mass transport in the ocean interior on the space scales considered here, namely, on the order of a few thousand kilometers. However, regions in which 226Ra and Ba displayed nonconservative behavior and in some cases decoupled behaviors were also identified, mostly at the ocean boundaries (seafloor, continental margins and surface waters). Elevated 226Ra and Ba concentrations found in deepwater in the West European Basin suggest that lower Northeast Atlantic Deep Water (NEADWl) accumulates 226Ra and Ba from sediment diffusion and/or particle dissolution during transport. In the upper 1500 m of the West European Basin, deficiencies in 226Ra and Ba are likely explained by their incorporation in planktonic calcareous

  16. Vakumla Paketlenen İnegöl Köftelerin Farklı Derecelerde Buzdolabında Saklanması Sırasında Bakteri Florasında ve Listeria monocytogenes Sayısındaki Değişiklikler

    Directory of Open Access Journals (Sweden)

    Ece Soyutemiz

    2015-02-01

    Full Text Available Çalışma, günümüzde hazır olarak satışı yaygınlaşan inegöl köftenin vakumla paketlenerek farklı derecelerde muhafazası sırasın­da köftenin bakteri florasını ve L. monocytogenes 'ingelişimini incelemek amacıyla yapıldı. Birinci grup köftelere 4.0x103 kob/g, 9.0x103 kob/g ve 2.4x104 kob/g düzeylerinde 3 farklı L. monocytogenes inokülasyonu uygulanarak, va­kumla paketleme işleminden sonra 7 gün süreyle 4°C'de muhafaza edildi, ikinci grup köftelere ise, 2,9x103 kob/g, 7.0x102 kob/g ve 4.3x103 kob/g düzeylerinde etken inoküle edilerek vakumla paketlendi ve 4°C'de 7 gün süreyle muhafaza edildi. Ayrıca köfteler mezofil aerob bakteri, psikrofil bakteriler, koliform bakteriler, E.coli,stafilokok ve mikrokoklar, koagülaz pozitif stafilokoklar, sülfit indirgeyen anaeroblar, laktobasiller, maya-küf ve enterokoklar bakımından analizlere alındı. Köftelerin ayrınca pH değerleri belirtendi. Analizler depolamanın 0, 1, 2, 3, 4, 5, 6 ve 7. günlerinde yapıldı. İnegöl köftelerin, vakumla paketlenerek 0°C'de ve 4°C'de muhafaza işlemi L. monocytogenes 'inçoğalmasını önlese bile etken bu süre içinde varlığını sürdürmeye devam etti. Bu nedenle köfte yapımında hijyen prensiplerinin ve köftelere yeterli ızgara işlemi uygulamasının önem ka­zandığı düşünüldü.

  17. Water adsorption induced in-plane domain switching on BaTiO{sub 3} surface

    Energy Technology Data Exchange (ETDEWEB)

    Li, X.; Bai, Y.; Su, Y. J., E-mail: yjsu@ustb.edu.cn [Corrosion and Protection Center, Key Laboratory for Environmental Fracture (MOE), University of Science and Technology Beijing, Beijing 100083 (China); Wang, B. C. [Corrosion and Protection Center, Key Laboratory for Environmental Fracture (MOE), University of Science and Technology Beijing, Beijing 100083 (China); Multiscale Materials Modelling group, Department of Materials and Engineering, Royal Institute of Technology, SE-10044 Stockholm (Sweden)

    2015-09-07

    In this study, the influences of the adsorption of water molecules on the changes in the atomic and electric structures of BaTiO{sub 3} surface were investigated using ab initio calculation. Water molecules are molecularly and dissociatively adsorbed on the BaTiO{sub 3} surface, which makes electrons transfer from water molecules to the BaTiO{sub 3} surface. The redistribution of electrons in the BaTiO{sub 3} surface layers weakens the Ba-O interactions and strengthens the Ti-O interactions, so that the Ti atom shifts in TiO{sub 2} plane, i.e., an in-plane domain switching. The adsorption of water molecules on BaTiO{sub 3} surfaces also results in a reduction in the surface rumpling.

  18. Growth of single crystals of BaFe12O19 by solid state crystal growth

    Science.gov (United States)

    Fisher, John G.; Sun, Hengyang; Kook, Young-Geun; Kim, Joon-Seong; Le, Phan Gia

    2016-10-01

    Single crystals of BaFe12O19 are grown for the first time by solid state crystal growth. Seed crystals of BaFe12O19 are buried in BaFe12O19+1 wt% BaCO3 powder, which are then pressed into pellets containing the seed crystals. During sintering, single crystals of BaFe12O19 up to ∼130 μm thick in the c-axis direction grow on the seed crystals by consuming grains from the surrounding polycrystalline matrix. Scanning electron microscopy-energy dispersive spectroscopy analysis shows that the single crystal and the surrounding polycrystalline matrix have the same chemical composition. Micro-Raman scattering shows the single crystal to have the BaFe12O19 structure. The optimum growth temperature is found to be 1200 °C. The single crystal growth behavior is explained using the mixed control theory of grain growth.

  19. Left posterior BA37 is involved in object recognition: a TMS study

    DEFF Research Database (Denmark)

    Stewart, Lauren; Meyer, Bernd-Ulrich; Frith, Uta

    2001-01-01

    Functional imaging studies have proposed a role for left BA37 in phonological retrieval, semantic processing, face processing and object recognition. The present study targeted the posterior aspect of BA37 to see whether a deficit, specific to one of the above types of processing could be induced...... to name pictures when TMS was given over lBA37 compared to vertex or rBA37. rTMS over lBA37 had no significant effect on word reading, nonword reading or colour naming. The picture naming deficit is suggested to result from a disruption to object recognition processes. This study corroborates the finding...... from a recent imaging study, that the most posterior part of left hemispheric BA37 has a necessary role in object recognition....

  20. Determination of the UO2-ZrO2-BaO equilibrium diagram

    International Nuclear Information System (INIS)

    Paschoal, J.O.A.; Kleykanp, H.; Thuemmler, F.

    1984-01-01

    It is determined the equilibrium diagram of UO 2 - ZrO 2 - BaO to interpret and predict changes in the chemical properties of ceramic (oxide) nuclear fuels during irradiation. The isothermal section of the system at 1700 0 C was determined experimentally, utilizing the techniques of ceramography, X-ray diffraction analysis, microprobe analysis and differential thermal analysis. The solid solubility limits at 1700 0 C between UO 2 and ZrO 2 , UO 2 and BaO, ZrO 2 and BaO, ZrO 2 and BaO and BaUO 3 and BaZrO 3 is presented. The influence of oxygen potential in relation to the different phases is discussed and the phase diagram of the system presented. (M.C.K.) [pt

  1. Structure and stability of BaTiSi₂O₇.

    Science.gov (United States)

    Viani, Alberto; Palermo, Andrea; Zanardi, Stefano; Demitri, Nicola; Petrícek, Václav; Varini, Federico; Belluso, Elena; Ståhl, Kenny; Gualtieri, Alessandro Francesco

    2015-04-01

    Due to their optical, photo-luminescence (PL), and afterglow properties, barium titanosilicates are compounds of great interest for functional materials and light-emitting devices. Among them, BaTiSi2O7 (BTS2) is certainly one of the most intriguing; it displays peculiar properties (e.g. PL orange emission) whose exhaustive explanation has been hampered to date by the lack of a structure model. In this work, BTS2 and the related compound BaTiSi4O11 (BTS4) were synthesized through conventional solid-state reaction methods. BTS2 invariably shows complex twinning patterns. Thus, its structure solution and Rietveld structure refinement were attempted using synchrotron powder diffraction. BTS2 was found to be an intergrowth of monoclinic and triclinic crystals. The monoclinic phase has the space group P21/n and unit cell a = 7.9836 (3), b = 10.0084 (4), c = 7.4795 (3) Å, and β = 100.321 (3)°, whereas the triclinic phase has the space group P\\bar 1 and unit cell a = 7.99385 (4), b = 10.01017 (5), c = 7.47514 (3) Å, α = 90.084 (8), β = 100.368 (8) and γ = 89.937 (9)°. These lattices can be seen as a distortion of that of tetragonal synthetic β-BaVSi2O7 with Ti in place of V. The structure models obtained from this study confirm the presence of fivefold coordinated Ti atoms in a distorted pyramidal configuration. The proposed solution supports existing theories for the explanation of the PL orange colour in BTS2.

  2. NUCLEI OF DESERTIFICATION IN STATE OF PARAÍBA

    Directory of Open Access Journals (Sweden)

    Jose Jakson Amancio Alves

    2009-06-01

    Full Text Available The present work boards desertification problem in Paraíba who directly is related to degradation produced by the man in the stunted sparse forest and in the environmental terms and fitogeography of this geoecosystem. The domain geoecology of the stunted sparse forests extends for about 1037.517,80 km², under the latitudes between tropics, comprehended between 2º 45’ and 17º 21’ LS.  Its area corresponds to 54% of the region Northeast and to 11% of the brazilian territory; it constitutes the droughts called polygon. In the stunted sparse forest the woody species call the attention for their biological forms and by the dominant position in the formation structure. In magnitude function of these characteristic, that corresponds to the largest problem in desertification cores generation in state of Paraíba. These woody species of rickety postage are the appreciated most for the burning in coal-pits, bakeries oven, etc. they are fácies more drought and degraded of the stunted sparse forests. Another aspect to observe is that to the natural fragility of this ecosystem brings serious consequences for geótopos and for biocenoses, as well as, the devastation practice of great spaces by the burnt for the pasture areas, provoking great unbalance in the ecosystem and contributing with the earth’s degradation process. That work points a series of surveys that emphasize that process in state of Paraíba, as well as, a contribution for contention of their effects.

  3. An ABO blood grouping discrepancy: Probable B(A) phenotype.

    Science.gov (United States)

    Jain, Ashish; Gupta, Anubhav; Malhotra, Sheetal; Marwaha, Neelam; Sharma, Ratti Ram

    2017-06-01

    In B(A) phenotype, an autosomal dominant phenotype, there is a weak A expression on group B RBCs. We herein report a case of a probable B(A) phenotype in a first time 20-year old male donor. The cell and serum grouping were done using tube technique and also with blood grouping gel card (Diaclone, ABD cards for donors, BioRad, Switzerland). The antisera used were commercial monoclonal IgM type. To check for the weak subgroup of A, cold adsorption and heat elution was performed. The cell grouping was A weak B RhD positive while the serum grouping was B. There was no agglutination with O cells and the autologous control was also negative. It was a group II ABO discrepancy with or without group IV discrepancy. Results for both the eluate and last wash were negative. Hence, the possibility of weak subgroup of A was unlikely. Blood grouping gel card also showed a negative reaction in the anti-A column. One lot of anti-A was showing 'weak +' agglutination while the other lot was showing 'negative' reaction with the donor RBCs by tube technique. There was no agglutination observed with anti-A1 lectin. Our case highlights the serological characteristics of a B(A) phenotype. This case emphasizes the vital role of cell and serum grouping in detecting such discrepancies especially in donors which can lead to mislabeling of the blood unit and may be a potential risk for the transfusion recipient if not resolved appropriately. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. THINNING OF ‘GALA’ AND 'GOLDEN DELICIOUS' APPLES WITH BA, NAA AND THEIR COMBINATIONS

    Directory of Open Access Journals (Sweden)

    M STOPAR

    2002-07-01

    Full Text Available Apple trees, eight-year-old ‘Gala’/M.9 and four-year-old ‘Golden Delicious’/M.9 have been thinned with 6- benzyladenine (BA 50 ppm, 100 ppm and 200 ppm, with 1-naphthaleneacetic acid (NAA 5 ppm, 10 ppm and 20 ppm, and with the tank mix combinations of BA 50 ppm + NAA 5 ppm or BA 20 ppm + NAA 5 ppm, all at 9-10 mm fruitlet diameter. All applied concentrations of BA and NAA thinned both cultivars significantly and no significant difference was found between BA or NAA thinning action. No concentration response on thinning was observed with neither BA nor NAA application. All BA or NAA separate treatments caused yield of fruit to shift to bigger size class. The only concentration response effect was found on evaluation of mean fruit weight data on ‘Golden Delicious’. The higher concentration of BA was used, the higher was the weight of ‘Golden Delicious’ fruit. On the opposite, the higher concentration of NAA was used, the lower was the weight of ‘Golden Delicious’ fruit (not significantly. When BA and NAA were sprayed on ‘Gala’ or ‘Golden Delicious’ as a tank mix combination, similar effect on thinning or fruit growth occurred comparing to BA or NAA when sprayed alone. Return bloom was enhanced on all thinned ‘Gala’ trees while flower formation of ‘Golden Delicious’ was better in the case of BA 200 ppm, NAA 5 ppm, NAA 20 ppm or tank mix spraying of BA 20 ppm + NAA 5 ppm.

  5. Quo Vadis the B.A. degree: Perceptions and visions1

    Directory of Open Access Journals (Sweden)

    Annette L. Combrink

    1993-03-01

    Full Text Available Today is a very special day for all the graduates assembled to have a B.A. degree conferred on them. It is a day on which to celebrate the reward for hard work and for realized dreams. This is a very homogeneous group of people - in the sense that they will be receiving B.A. degrees, and for that reason it would be highly apposite to share some cherished thought and ideas about the B.A. degree.

  6. Microstructural properties of BaTiO3 ceramics and thin films

    International Nuclear Information System (INIS)

    Fundora C, A.; Portelles, J.J.; Siqueiros, J.M.

    2000-01-01

    A microstructural study of BaTiO 3 ceramics obtained by the conventional ceramic method is presented. Targets were produced to grow BaTiO 3 thin films by pulsed laser deposition on Pt/Ti/Si (100) substrates. X-ray diffraction, Auger Electron Spectroscopy, X-ray Photon Spectroscopy and Scanning Electron Microscopy were used to study the properties of the BaTiO 3 ceramic samples and thin films, as deposited and after an annealing process. (Author)

  7. Muon spin depolarization in Gd- and EuBa2Cu3Ox

    International Nuclear Information System (INIS)

    Cooke, D.W.; Hutson, R.L.; Kwok, R.S.; Maez, M.; Rempp, H.; Schillaci, M.E.; Smith, J.L.; Willis, J.O.; Lichti, R.L.; Chan, K.C.; Boekema, C.; Weathersby, S.; Oostens, J.

    1989-01-01

    Positive muon spin rotation (μSR) measurements on Gd- and EuBa 2 Cu 3 O x (x ∼ 7) have been conducted in the temperature interval 4 - 300 K. For each sample, muons stop both at grain boundaries and within the superconducting grains. Measured magnetic field penetration depths are 1550 and 1900 Angstrom for two specimens of GdBa 2 Cu 3 O x , and 1350 Angstrom for EuBa 2 Cu 3 O x

  8. BACTERICIDAL COATINGS ON TEXTILES FOR REMEDIATION OF INTERMICROBE ACTIVITY (BaCTeRIA) SUMMARY REPORT

    Science.gov (United States)

    2017-07-07

    TEXTILES FOR REMEDIATION OF INTERMICROBE ACTIVITY (BaCTeRIA) SUMMARY REPORT by Tobyn A. Branck Courtney M. Cowell Jennifer M. Rego and...October 2011 – September 2015 4. TITLE AND SUBTITLE BACTERICIDAL COATINGS ON TEXTILES FOR REMEDIATION OF INTERMICROBE ACTIVITY (BaCTeRIA) SUMMARY REPORT... REMEDIATION OF INTERMICROBE ACTIVITY (BaCTeRIA) SUMMARY REPORT Introduction The Biological Sciences and Technology Team (BSTT), Warfighter

  9. Synthesis of BaTiO3 powder from barium titanyl oxalate (BTO ...

    Indian Academy of Sciences (India)

    Unknown

    the synthesis of BaTiO3 from the mixture of barium car- bonate and titanium dioxide employing microwave heat- ing. They observed that hypostoichiometric TiO2 (TiO2–x) reacted with BaCO3 in the presence of microwave field at temperature as low as 350°C to give the mixture of hexa- gonal and tetragonal forms of BaTiO3 ...

  10. Excitation of high spin levels in 129Ba

    International Nuclear Information System (INIS)

    Gizon, J.; Gizon, A.

    1976-01-01

    The level structure of 129 Ba has been studied by the 120 Sn( 12 C,3nγ) reaction. A set of negative-parity levels based upon a 9/2 - state is interpreted in terms of the rotation-alignment coupling of hsub(11/2) neutron holes to the triaxial core. A new band structure built upon a 7/2 + state is also observed. It could be due to the coupling of a gsub(7/2) neutron hole to the triaxial core [fr

  11. Phase stabilization in plasma sprayed BaTiO3

    Czech Academy of Sciences Publication Activity Database

    Ctibor, Pavel; Seiner, Hanuš; Sedláček, J.; Pala, Zdeněk; Vaněk, Přemysl

    2013-01-01

    Roč. 39, č. 5 (2013), s. 5039-5048 ISSN 0272-8842 R&D Projects: GA ČR(CZ) GA101/09/0702 Institutional support: RVO:61389021 ; RVO:61388998 ; RVO:68378271 Keywords : Spectroscopy * BaTiO3 * Plasma spraying * Spark plasma sintering Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass; BJ - Thermodynamics (UT-L); JH - Ceramics, Fire-Resistant Materials and Glass (FZU-D) Impact factor: 2.086, year: 2013 http://www.sciencedirect.com/science/article/pii/S0272884212013582

  12. Camino Inca Cajamarca – Baños del Inca

    OpenAIRE

    Camargo Mareovich, Cecilia; León Ascurra, Wilder Javier

    2014-01-01

    En 1532 los capitanes Hernando de Soto y Hernando Pizarro recorrieron un antiguo camino desde la actual Plaza de Armas de Cajamarca hasta los Baños del Inca para entrevistarse con el Inca Atahualpa, quien recorrió por última vez este camino para su encuentro con Francisco Pizarro y sus huestes un 16 de noviembre de 1532. Esta información fue tomada de las descripciones del asentamiento inca que hicieran Hernando Pizarro (1537), Francisco de Xerez (1534), Miguel de Estete (1534), entre otros, ...

  13. Design of a minimum emittance nBA lattice

    Science.gov (United States)

    Lee, S. Y.

    1998-04-01

    An attempt to design a minimum emittance n-bend achromat (nBA) lattice has been made. One distinct feature is that dipoles with two different lengths were used. As a multiple bend achromat, five bend achromat lattices with six superperiod were designed. The obtained emittace is three times larger than the theoretical minimum. Tunes were chosen to avoid third order resonances. In order to correct first and second order chromaticities, eight family sextupoles were placed. The obtained emittance of five bend achromat lattices is almost equal to the minimum emittance of five bend achromat lattice consisting of dipoles with equal length.

  14. Pressure dependence of BaNi2As2

    Energy Technology Data Exchange (ETDEWEB)

    Ronning, Filip [Los Alamos National Laboratory; Park, Tuscon [Los Alamos National Laboratory; Bauer, Eric D [Los Alamos National Laboratory; Thompson, Joe D [Los Alamos National Laboratory

    2009-01-01

    We report results from resistivity measurements of BaNi{sub 2}As{sub 2} up to 27.4 kbar of pressure. We find the structural transition at 130 K is broadened slightly with increasing pressure. There is also minimal influence on the superconducting transition, where the resistive onset increases from 2 to 3 K, but the temperature at which zero resistance is obtained is unchanged up to 27.4 kbar. This behavior is in contrast to that observed in the Fe-based systems as well as in LaNiPO and LaNiAsO.

  15. Managing the BaBar object oriented database

    International Nuclear Information System (INIS)

    Hasan, A.; Trunov, A.

    2001-01-01

    The BaBar experiment stores its data in an Object Oriented federated database supplied by Objectivity/DB(tm). This database is currently 350TB in size and is expected to increase considerably as the experiment matures. Management of this database requires careful planning and specialized tools in order to make the data available to physicists in an efficient and timely manner. The authors discuss the operational issues and management tools that were developed during the previous run to deal with this vast quantity of data at SLAC

  16. Thermal analysis of formation of nano-crystalline BaTiO3 using Ba(NO32 and TiO2

    Directory of Open Access Journals (Sweden)

    Md. Jawed Ansaree

    2015-12-01

    Full Text Available The reaction of Ba(NO32 with TiO2 was studied by thermogravimetric (TG and differential scanning calorimetric (DSC techniques up to 1000 °C and in nitrogen atmosphere. It was found that the formation of BaTiO3 takes place above 600 °C and that precursor mixing time and heating rate have no effect on the reaction temperature. BaTiO3 powder was prepared by calcination of Ba(NO32 and TiO2 precursor mixture at 800 °C for 8 h. X-ray diffraction analysis of the synthesized BaTiO3 confirmed the formation of tetragonal phase with lattice parameters a = 3.9950±0.0003 Å and c = 4.0318±0.0004 Å. Thermal analysis of the synthesized BaTiO3 powder showed weight loss within temperature range 40–1000 °C of only 0.40%. This small amount of weight loss was connected with some impurity phase, and identified as BaCO3 using Fourier transform infrared (FTIR technique.

  17. Epitaxial thin-film growth of Ruddlesden-Popper-type Ba3Zr2O7 from a BaZrO3 target by pulsed laser deposition

    International Nuclear Information System (INIS)

    Butt, Shariqa Hassan; Rafique, M.S.; Siraj, K.; Latif, A.; Afzal, Amina; Awan, M.S.; Bashir, Shazia; Iqbal, Nida

    2016-01-01

    Ruddlesden-Popper Ba 3 Zr 2 O 7 thin films have been synthesized via pulsed laser deposition (PLD) technique. The optimization of deposition parameters in PLD enables the formation of thin film of metastable Ba 3 Zr 2 O 7 phase from BaZrO 3 target. In order to see the post-annealing effects on the structural and optical properties, the deposited Ba 3 Zr 2 O 7 thin films were annealed at 500, 600 and 800 C. X-ray diffraction (XRD) reveals the formation of Ba 3 Zr 2 O 7 phase with tetragonal structure. The changes in the surface of the deposited films were analysed by FE-SEM and AFM. The thin film post-annealed at 500 C exhibited the best structural, optical and surface properties. Furthermore, the chemical states and chemical composition of the films were determined by X-ray photoelectron spectroscopy (XPS) near the surface. The XPS results show that Ba, Zr and O exist mainly in the form of Ba 3 Zr 2 O 7 Ruddlesden-Popper-type perovskite structure. (orig.)

  18. Er3+ infrared fluorescence affected by spatial distribution synchronicity of Ba2+ and Er3+ in Er3+-doped BaO–SiO2 glasses

    Directory of Open Access Journals (Sweden)

    Atsunobu Masuno

    2016-02-01

    Full Text Available Glasses with the composition xBaO–(99.9 − xSiO2–0.1ErO3/2 (0 ≤x ≤ 34.9 were fabricated by a levitation technique. The glasses in the immiscibility region were opaque due to chemical inhomogeneity, while the other glasses were colorless and transparent. The scanning electron microscope observations and electron probe microanalysis scan profiles revealed that more Er3+ ions were preferentially distributed in the regions where more Ba2+ ions existed in the chemically inhomogeneous glasses. The synchronicity of the spatial distributions of the two ions initially increased with increasing x and then decreased when the Ba2+ concentration exceeded a certain value. The peak shape and lifetime of the fluorescence at 1.55 μm depended on x as well as the spatial distribution of both ions. These results indicate that although ErOn polyhedra are preferentially coordinated with Ba2+ ions and their local structure is affected by the coordination of Ba2+, there is a maximum in the amount of Ba2+ ions that can coordinate ErOn polyhedra since the available space for Ba2+ ions is limited. These findings provide us with efficient ways to design the chemical composition of glasses with superior Er3+ fluorescence properties for optical communication network systems.

  19. Spectral analysis of Pr{sup 3+} doped germanate glasses modified by BaO and BaF{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Pisarska, Joanna, E-mail: joanna.pisarska@us.edu.pl [University of Silesia, Institute of Chemistry, Szkolna 9 Street, 40-007 Katowice (Poland); Pisarski, Wojciech A. [University of Silesia, Institute of Chemistry, Szkolna 9 Street, 40-007 Katowice (Poland); Dorosz, Dominik; Dorosz, Jan [Bialystok University of Technology, Faculty of Electrical Engineering, Wiejska 45D Street, 15-351 Bialystok (Poland)

    2016-03-15

    Luminescence properties of Pr{sup 3+} ions in germanate glasses modified by BaF{sub 2} were investigated. Several luminescence bands originating to transitions from the {sup 3}P{sub 0} state to the lower-lying states of Pr{sup 3+} were registered under 450 nm excitation. The spectral analysis suggests that the positions of luminescence bands and their relative intensities are changed significantly with BaF{sub 2} content. The relative integrated luminescence intensities of {sup 3}P{sub 0}→{sup 3}H{sub 4} transition (blue) to the {sup 3}P{sub 0}→{sup 3}F{sub 2} transition (red) of Pr{sup 3+} ions strongly depend on fluoride modifier BaF{sub 2} in glass composition. The luminescence bands of Pr{sup 3+} ions are shifted to shorter wavelengths with increasing BaF{sub 2} content. - Highlights: • Praseodymium doped lead-free germanate glasses modified by BaF{sub 2} were prepared. • Emission spectra correspond to transitions from {sup 3}P{sub 0} state to lower-lying states of Pr{sup 3+}. • The relative emission band intensities of Pr{sup 3+} depend strongly on BaF{sub 2} content. • Emission bands of Pr{sup 3+} are shifted to shorter wavelengths with increasing BaF{sub 2} content.

  20. Preparation and self-assembly of nanostructured BaCrO4 from CTAB reverse microemulsions

    International Nuclear Information System (INIS)

    Li Zhonghao; Zhang Jianling; Du Jimin; Han Buxing; Mu Tiancheng; Gao Yanan; Liu Zhimin

    2005-01-01

    Well-defined superstructures of rectangular-shaped BaCrO 4 and extensive network of BaCrO 4 nanoparticles constructed by self-assembly were prepared in cetyltrimethylammonium bromide (CTAB) reverse microemulsions. The effects of aging time and reactant concentrations on the morphology and the self-assemble pattern of the nanostructured BaCrO 4 were investigated. TEM combined with the electron diffraction was used to characterize the morphology and the crystal structure of the prepared nanostructured BaCrO 4 at different conditions

  1. Enhanced 77 K vortex-pinning in Y Ba2Cu3O7−x films with Ba2Y TaO6 and mixed Ba2Y TaO6 + Ba2Y NbO6 nano-columnar inclusions with irreversibility field to 11 T

    Directory of Open Access Journals (Sweden)

    F. Rizzo

    2016-06-01

    Full Text Available Pulsed laser deposited thin Y Ba2Cu3O7−x (YBCO films with pinning additions of 5 at. % Ba2Y TaO6 (BYTO were compared to films with 2.5 at. % Ba2Y TaO6 + 2.5 at. % Ba2Y NbO6 (BYNTO additions. Excellent magnetic flux-pinning at 77 K was obtained with remarkably high irreversibility fields greater than 10 T (YBCO-BYTO and 11 T (YBCO-BYNTO, representing the highest ever achieved values in YBCO films.

  2. Nucleation control and inhibition of BaTiO3 films using hydrothermal-electrochemical method

    International Nuclear Information System (INIS)

    Escobar, Ivan; Silva, Carmen; Silva, Eric; Vargas, Tomas; Fuenzalida, Victor

    1999-01-01

    The microstructure of BaTiO 3 films on titanium by the hydrothermal-electrochemical method was investigated using a three electrode high pressure electrochemical cell in a 0.2 M Ba(OH) 2 electrolyte at 150 0 C. The spontaneous initial linked to pure hydrothermal BaTiO 3 formation can be inhibited by cathodically protecting titanium electrode since its immersion in the electrolyte. The application of initial nucleation pulses of varying the cathodic potentials affected the grain size of the deposit. It is suggested that the formation of a titanium oxide layers is a necessary step previous to the nucleation of BaTiO 3

  3. Beyond survival: fostering growth and innovation in doctoral study--a concept analysis of the Ba space.

    Science.gov (United States)

    Krahe, J A E; Lalley, Cathy; Solomons, Nan M

    2014-01-25

    This concept analysis examines the Ba space in the context of interdisciplinary doctoral study in nursing and healthcare innovation in a minimal residency program. The authors identified Ba in their small, highly diverse, self-selected doctoral study group and believe Ba is an educational innovation that will prove useful to nursing and healthcare educators. Ba originates from Japanese philosophy and is foundational to the birth and sustainment of environments fostering knowledge creation. Ba manifests in complex environments where participants are emotionally invested and relies on the tacit knowledge of each participant, allowing for synthesis of rationality and intuition. Walker and Avant's concept analysis methodology will explore Ba's centrality to interdisciplinary education. Ba's utility and application in fostering innovation in doctoral study will be illustrated. Ba is a true educational innovation, enriching learning environments promoting interdisciplinary collaboration. Ba permits each member a voice and fosters a safe environment where relationships are created and sustained.

  4. How Extended Is Wernicke’s Area? Meta-Analytic Connectivity Study of BA20 and Integrative Proposal

    Directory of Open Access Journals (Sweden)

    Alfredo Ardila

    2016-01-01

    Full Text Available Understanding the functions of different brain areas has represented a major endeavor of contemporary neurosciences. The purpose of this paper was to pinpoint the connectivity of Brodmann area 20 (BA20 (inferior temporal gyrus, fusiform gyrus in language tasks. A meta-analysis was conducted to assess the language network in which BA20 is involved. The DataBase of Brainmap was used; 11 papers corresponding to 12 experimental conditions with a total of 207 subjects were included in this analysis. Our results demonstrated seven clusters of activation including other temporal lobe areas (BA3, BA21, the insula, and the prefrontal cortex; minor clusters in the cingulate gyrus and the occipital lobe were observed; however, the volumes of all the activation clusters were small. Our results suggest that regardless of BA20 having certain participation in language processes it cannot be considered as a core language processing area (Wernicke’s area; nonetheless, it could be regarded as kind of language processing marginal area, participating in “extended Wernicke’s area” or simply “Wernicke’s system.” It is suggested that “core Wernicke’s area” roughly corresponds to BA21, BA22, BA41, and BA42, while a “language associations area” roughly corresponds to BA20, BA37, BA38, BA39, and BA40 (“extended Wernicke’s area” or “Wernicke’s system”.

  5. Structural and electrical properties of Barium Titanate (BaTiO3 and Neodymium doped BaTiO3 (Ba0.995Nd0.005TiO3

    Directory of Open Access Journals (Sweden)

    Tuan Sulong Tuan Amirah

    2017-01-01

    Full Text Available Barium titanate (BaTiO3 and Neodymium (Nd doped BaTiO3 with composition Ba0.995Nd0.005TiO3 were prepared using conventional solid state reaction method to study the dielectric properties of materials. Pure phase samples were found at final heating temperature of 1400°C for overnight. X-ray diffraction analysis reveals the changes in the lattice parameter and unit cell volume of the pure perovskite tetragonal structure with space group (P4mm. Electrical analysis is carried out to investigate the dielectric properties, conductivity behaviour and dielectric loss of BaTiO3 and Ba0.995Nd0.005TiO3. Ba0.995Nd0.005TiO3 have a broaden dielectric peaks with high permittivity of 8000 and reasonably low loss tan δ which is about 0.004 (1 kHz.

  6. Fatigue and retention in ferroelectric Y-Ba-Cu-O/Pb-Zr-Ti-O/Y-Ba-Cu-O heterostructures

    Science.gov (United States)

    Ramesh, R.; Chan, W. K.; Wilkens, B.; Gilchrist, H.; Sands, T.; Tarascon, J. M.; Keramidas, V. G.; Fork, D. K.; Lee, J.; Safari, A.

    1992-09-01

    Fatigue and retention characteristics of ferroelectric lead zirconate titanate thin films grown with Y-Ba-Cu-O(YBCO) thin-film top and bottom electrodes are found to be far superior to those obtained with conventional Pt top electrodes. The heterostructures reported here have been grown in situ by pulsed laser deposition on yttria-stabilized ZrO2 buffer [100] Si and on [001] LaAlO3. Both the a- and c-axis orientations of the YBCO lattice have been used as electrodes. They were prepared using suitable changes in growth conditions.

  7. Theoretical studies of superconductivity in doped BaCoSO

    Science.gov (United States)

    Qin, Shengshan; Li, Yinxiang; Zhang, Qiang; Le, Congcong; Hu, Jiangping

    2018-06-01

    We investigate superconductivity that may exist in the doped BaCoSO, a multi-orbital Mott insulator with a strong antiferromagnetic ground state. The superconductivity is studied in both t-J type and Hubbard type multi-orbital models by mean field approach and random phase approximation (RPA) analysis. Even if there is no C 4 rotational symmetry, it is found that the system still carries a d-wave like pairing symmetry state with gapless nodes and sign changed superconducting order parameters on Fermi surfaces. The results are largely doping insensitive. In this superconducting state, the three {t_{{2_g}}} orbitals have very different superconducting form factors in momentum space. In particular, the intra-orbital pairing of the {d_{{x^2} - {y^2}}} orbital has an s-wave like pairing form factor. The two methods also predict very different pairing strength on different parts of Fermi surfaces. These results suggest that BaCoSO and related materials can be a new ground to test and establish fundamental principles for unconventional high temperature superconductivity.

  8. BaBar computing - From collisions to physics results

    CERN Multimedia

    CERN. Geneva

    2004-01-01

    The BaBar experiment at SLAC studies B-physics at the Upsilon(4S) resonance using the high-luminosity e+e- collider PEP-II at the Stanford Linear Accelerator Center (SLAC). Taking, processing and analyzing the very large data samples is a significant computing challenge. This presentation will describe the entire BaBar computing chain and illustrate the solutions chosen as well as their evolution with the ever higher luminosity being delivered by PEP-II. This will include data acquisition and software triggering in a high availability, low-deadtime online environment, a prompt, automated calibration pass through the data SLAC and then the full reconstruction of the data that takes place at INFN-Padova within 24 hours. Monte Carlo production takes place in a highly automated fashion in 25+ sites. The resulting real and simulated data is distributed and made available at SLAC and other computing centers. For analysis a much more sophisticated skimming pass has been introduced in the past year, ...

  9. Charmed-B decays at BaBar

    International Nuclear Information System (INIS)

    Tisserand, Vincent

    2004-01-01

    We present recent results on charmed-B decays using data collected by the BaBaR experiment at the PEP-II storage ring. This report is subdivided in 3 parts. In a first step, we present preliminary results on the measurement of the branching fractions of seven color-suppressed anti B 0 -meson decays into D (*)0 π 0 , D (*)0 η, D (*)0 ω, and D 0 η ' . Then we discuss the preliminary measurement of the ratio of Cabibbo-suppressed to Cabibbo-favored branching fractions B(B - →D 0 K - )/B(B - →D 0 π - ), where the D 0 is possibly reconstructed in the CP-even π - π + and K - K + modes. For the D 0 decays into CP-eigenstates, a search for a direct CP asymmetry is performed. For the same category of decay processes, we show a precise preliminary measurement of both the branching fraction of B - decaying to D *0 K *- and of the fraction of longitudinal polarization in this decay. Finally, we present a study where the 22 possible B decays to anti D (*) D * K are reconstructed exclusively. The branching fractions of the anti B 0 and of the B + to anti D (*) D (*) K are presented and a search for decays B→anti D (*) D sJ + (→D (*)0 K + ), where the D sJ + represents the orbitally excited D s states, is also discussed. (orig.)

  10. Observation of superconductivity in BaNb2S5

    Science.gov (United States)

    Smith, M. G.; Neumeier, J. J.

    2018-06-01

    Bulk superconductivity is reported in BaNb2S5 at the transition temperature Tc = 0.85(1) K. The electrical resistivity ρ versus T is metallic with ρ(2 K) = 42.4 μΩ cm. The magnetic susceptibility is paramagnetic, with temperature-independent contributions due to diamagnetism, Pauli paramagnetism, and Van Vleck paramagnetism; a Curie-Weiss contribution appears to be impurity related. Hall effect measurements show that the majority charge carriers are electrons with charge-carrier concentration n(3 K) = 2.40(2) × 1021 cm-3. Specific heat measurements reveal an electronic specific heat coefficient γ = 11.2(1) mJ/mol K2, a Debye temperature ΘD = 126.4(8) K, and an energy gap associated with the superconducting state of Eg = 0.184(4) meV. Measurements of ρ(T) in magnetic field provide the upper critical magnetic field of about 3055(74) Oe as T → 0 K, which was used to estimate the coherence length ξ = 6.21(15) nm. The results allow classification of BaNb2S5 as a Type II, BCS superconductor in the dirty limit.

  11. Stellar laboratories. III. New Ba v, Ba vi, and Ba vii oscillator strengths and the barium abundance in the hot white dwarfs G191-B2B and RE 0503-289

    Science.gov (United States)

    Rauch, T.; Werner, K.; Quinet, P.; Kruk, J. W.

    2014-06-01

    Context. For the spectral analysis of high-resolution and high-signal-to-noise (S/N) spectra of hot stars, state-of-the-art non-local thermodynamic equilibrium (NLTE) model atmospheres are mandatory. These are strongly dependent on the reliability of the atomic data that is used for their calculation. Aims: Reliable Ba v-vii oscillator strengths are used to identify Ba lines in the spectra of the DA-type white dwarf G191-B2B and the DO-type white dwarf RE 0503-289 and to determine their photospheric Ba abundances. Methods: We newly calculated Ba v-vii oscillator strengths to consider their radiative and collisional bound-bound transitions in detail in our NLTE stellar-atmosphere models for the analysis of Ba lines exhibited in high-resolution and high-S/N UV observations of G191-B2B and RE 0503-289. Results: For the first time, we identified highly ionized Ba in the spectra of hot white dwarfs. We detected Ba vi and Ba vii lines in the Far Ultraviolet Spectroscopic Explorer (FUSE) spectrum of RE 0503-289. The Ba vi/Ba vii ionization equilibrium is well reproduced with the previously determined effective temperature of 70 000 K and surface gravity of log g = 7.5. The Ba abundance is 3.5 ± 0.5 × 10-4 (mass fraction, about 23 000 times the solar value). In the FUSE spectrum of G191-B2B, we identified the strongest Ba vii line (at 993.41 Å) only, and determined a Ba abundance of 4.0 ± 0.5 × 10-6 (about 265 times solar). Conclusions: Reliable measurements and calculations of atomic data are a pre-requisite for stellar-atmosphere modeling. Observed Ba vi-vii line profiles in two white dwarfs' (G191-B2B and RE 0503-289) far-ultraviolet spectra were well reproduced with our newly calculated oscillator strengths. This allowed to determine the photospheric Ba abundance of these two stars precisely. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for

  12. Effect of Ba in the glass characteristics of cesium loaded iron phosphate glasses

    International Nuclear Information System (INIS)

    Joseph, Kitheri; Asuvathraman, R.; Vasudeva Rao, P.R.

    2015-01-01

    Radioactive 137 Cs extracted from high level nuclear waste, when immobilized in a suitable matrix can be used as a γsource in medical industry. Iron phosphate glass (IPG) is one of a suitable matrix for the immobilization of 137 Cs prior to the immobilization of 137 Cs in IPG, it is essential to optimize the immobilization conditions using natural (inactive) cesium. Glass characteristics of inactive Cs loaded iron phosphate glasses were already explored in our earlier studies. However, the change in glass characteristics of 137 Cs loaded iron phosphate glass to 137 Ba loaded iron phosphate glass need to be studied before the immobilization of 137 Cs in iron phosphate glass as 137 Cs transforms to 137 Ba due to nuclear transmutation ( 137 Cs(β,γ) 137 Ba). This paper reports the studies on such a behaviour by incorporating inactive Ba in cesium loaded iron phosphate glasses. Cs and Ba loaded iron phosphate glasses were prepared by melt quench technique in air using appropriate amounts of Fe 2 O 3 , NH 4 H 2 PO 4 , Ba(OH) 2.8 H 2 O and Cs 2 CO 3 . The chemicals were added such that the glass formed possesses the batch composition of (a) 21.4 wt. % Fe 2 O 3 -45 wt. % Cs 2 O-5 wt % BaO-P 2 O 5 (henceforth referred as IP50Cs45Ba5); (b) 21.4 wt. % Fe 2 O 3 -25 wt. % Cs 2 O-25 wt % BaO-P 2 O5 (henceforth referred as IP50Cs25Ba25). The thermal expansion measurements were also carried out using a home-built quartz push-rod dilatometer. The data related to change in thermal expansion behaviour, glass forming ability, glass stability and structural changes in phosphate network due to the partial replacement of Cs with Ba will also be discussed. (author)

  13. The microscopic twins and their crystal phase in the high Tc Y-Ba-Cu-O and Dy-Ba-Cu-O superconductive ceramics

    International Nuclear Information System (INIS)

    Zu, Z.J.; Chen, Y.L.

    1988-01-01

    Most consider that the structure of Y-Ba- Cu-O and Dy-Ba-Cu-O stable superconductive crystals with high Tc is associated with the right-angled phase. The superconductivity is closely connected with the right-angled character of the crystalline texture; the better the right- angled character, the better the superconductivity. From statistical investigations of examples the authors have discovered that most of the Y-Ba-Cu-O and Dy-Ba-Cu-O superconductivity with high Tc ceramic crystals is in the monoclinic phase, which, consists of microscopic, lamellar, single twins. The long-columnar grains consisting of lamellar twin slabs show the optical characteristics of right-angled phase. The microscopic twinning and grain morphologies are summarized in this paper

  14. Optical energy gaps and photoluminescence peaks of BaGa2S4:Er3+ and BaGa2Se4:Er3+ single crystals

    International Nuclear Information System (INIS)

    Choe, Sung-Hyu; Jin, Moon-Seog; Kim, Wha-Tek

    2005-01-01

    BaGa 2 S 4 :Er 3+ and BaGa 2 Se 4 :Er 3+ single crystals were grown by using the chemical transport reaction method. The optical energy gaps of the BaGa 2 S 4 :Er 3+ and the BaGa 2 Se 4 :Er 3+ single crystals were found to be 4.045 eV and 3.073 eV, respectively, at 11 K. The temperature dependence of the optical energy gap was well fitted by the Varshni equation. Sharp emission peaks were observed in the photoluminescence spectra of the single crystals and assigned to radiation recombination between split Stark levels of the Er 3+ ion.

  15. Identification of the neutron-rich nuclides /sup 147; 148/Ba and half- life determination of the heavy isotopes of Rb, Sr, Y, Cs, Ba and La

    CERN Document Server

    Amiel, S; Nir-El, Y; Shmid, M

    1976-01-01

    The neutron nuclides /sup 147; 148/Ba were produced in the thermal neutron induced fission of /sup 235/U. A new surface ionization integrated target ion source operating at temperatures in the region of 1800 degrees C permits the measurement of half-lives of isotopes down to about 0.1 sec due to the very fast release of atoms from the target. Isotopes of Rb, Sr, Cs, and Ba were separated by positive surface ionization and their half-lives measured using beta activity detected by a silicon surface barrier detector with a depletion depth of 300 mu . The isotopes /sup 147/Ba and /sup 148/Ba were identified for the first time and their half-lives were found to be 0.72+or-0.07 sec and 0.47+or-0.20 sec, respectively. (0 refs).

  16. Characterization and dielectric properties of BaTiO3 prepared from Ba(NO3)2-TiO2 mixture

    International Nuclear Information System (INIS)

    Othman, K.I.; Hassan, A.A.; Ali, M.E.; Abdelal, O.A.; Salah El Dien, F.E.; El-Raghy, S.M.; Abdel-Karim, R.

    2012-01-01

    BaTiO 3 powder was prepared through a solid-state reaction between the Ba(NO 3 ) 2 and TiO 2 . The thermal analysis and XRD techniques were used to study its formation. A single phase BaTiO 3 was formed after calcination at 600 degree C for 6 hrs. The dielectric properties of the sintered BaTiO 3 were determined in the temperature range from room temperature to 20 degree C at a frequency ranging from 500 Hz to 100 khz. The relative permittivity and the dielectric loss of the sintered pellets at 1 khz, measured at room temperature,were 1805 and 0.419 respectively.

  17. Flux pinning properties of ErBa2Cu3Oy thin films with BaZrO3 nanorods

    International Nuclear Information System (INIS)

    Haruta, M; Fujiyoshi, T; Sueyoshi, T; Dezaki, K; Ichigosaki, D; Miyahara, K; Miyagawa, R; Mukaida, M; Matsumoto, K; Yoshida, Y; Ichinose, A; Horii, S

    2006-01-01

    ErBa 2 Cu 3 O y (ErBCO) thin films with BaZrO 3 (BZO) nanorods were prepared by a PLD method for an enhancement of the critical current density J c . The values of J c for the ErBCO thin film containing 1.5 wt% BZO (Er15) in magnetic fields are higher than those for the ErBCO thin film containing 0.5 wt% BZO (Er05). The peaks of J c have been observed in the angular dependence of J c in both the films when the magnetic field is applied parallel to the c-axis. It has been found that the peak is attributed to the flux pinning by BZO nanorods oriented parallel to the c-axis. The vortex glass-liquid transition temperature T g and the pinning parameter m were derived by fitting observed electric transport properties to the theoretical expression based on the percolation transition model. The value of T g of Er15 is higher than that of Er05. This result indicates that the vortex glass phase extends to a higher temperature region on increasing the fraction of BZO. The peak of m has been found in the magnetic field dependence. This fact is probably due to matching the density of BZO nanorods with that of fluxoids, which was confirmed by TEM observations

  18. Molecular recognition at methyl methacrylate/n-butyl acrylate (MMA/nBA) monomer unit boundaries of phospholipids at p-MMA/nBA copolymer surfaces.

    Science.gov (United States)

    Yu, Min; Urban, Marek W; Sheng, Yinghong; Leszczynski, Jerzy

    2008-09-16

    Lipid structural features and their interactions with proteins provide a useful vehicle for further advances in membrane proteins research. To mimic one of potential lipid-protein interactions we synthesized poly(methyl methacrylate/ n-butyl acrylate) (p-MMA/nBA) colloidal particles that were stabilized by phospholipid (PLs). Upon the particle coalescence, PL stratification resulted in the formation of surface localized ionic clusters (SLICs). These entities are capable of recognizing MMA/nBA monomer interfaces along the p-MMA/nBA copolymer backbone and form crystalline SLICs at the monomer interface. By utilizing attenuated total reflectance Fourier transform infrared (ATR FT-IR) spectroscopy and selected area electron diffraction (SAD) combined with ab initio calculations, studies were conducted that identified the origin of SLICs as well as their structural features formed on the surface of p-MMA/nBA copolymer films stabilized by 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) PL. Specific entities responsible for SLIC formation are selective noncovalent bonds of anionic phosphate and cationic quaternary ammonium segments of DLPC that interact with two neighboring carbonyl groups of nBA and MMA monomers of the p-MMA/nBA polymer backbone. To the best of our knowledge this is the first example of molecular recognition facilitated by coalescence of copolymer colloidal particles and the ability of PLs to form SLICs at the boundaries of the neighboring MMA and nBA monomer units of the p-MMA/nBA chain. The dominating noncovalent bonds responsible for the molecular recognition is a combination of H-bonding and electrostatic interactions.

  19. Synthesis and luminescence properties of BaTiO3:RE (RE = Gd , Dy ...

    Indian Academy of Sciences (India)

    thermoluminescence (TL) properties of BaTiO3 samples doped with Gd3+, Dy3+, Tb3+ and Lu3+ were investigated. ... electron microscope using an accelerating voltage of 20 kV. .... doping of 1% mole Gd3+ ion into the BaTiO3 compound.

  20. Benzo(A)pyrene (BaP) treatment results in complete infertility in female pigeons

    Energy Technology Data Exchange (ETDEWEB)

    Hough, J.L.; Darrow, D.; Eaton, J.; Baird, M.B. (Masonic Medical Research Lab., Utica, NY (United States))

    1991-03-11

    BaP is a carcinogenic polycyclic aromatic hydrocarbon (PAH) and a common environmental pollutant. Show Racer and White Carneau female pigeons injected weekly with BaP for 3 for 5 months were completely infertile, with ovaries appearing necrotic or oxidized. Fertility in benzo(e)pyrene (BeP, a noncarcinogenic PAH) treated birds was the same as for corn oil treated controls, as was embryo development. Thus, infertility in BaP treated birds appears to be related to its structure-carcinogenic potential. There was no readily apparent affect of BaP treatment on testes from male birds. In order to determine whether BaP metabolites covalently bind to DNA in the ovaries of these birds, pigeons were injected with BaP or BeP, controls were injected with corn oil. Animals were sacrificed 24h later, the ovaries or testes removed, and the DNA isolated and analyzed for PAH-DNA adducts by {sup 32}P-post labeling assay. One major and one minor PAH-DNA adduct was found in ovaries and testes from BaP treated birds. However, no PAH adducts were found in BeP treated or control animals. Thus, problems with fertility may arise because of the alteration in DNA by BaP metabolite binding in ovaries where rapid cell growth occurs during egg production.

  1. Influence of seeding on crystallization behaviour of BaNaB9 glasses

    Indian Academy of Sciences (India)

    Administrator

    Influence of seeding on crystallization behaviour of BaNaB9. O15 glasses. RAHUL VAISH and K B R VARMA*. Materials Research Centre, Indian Institute of Science, Bangalore 560 012, India. MS received 18 August 2008. Abstract. Transparent BaNaB9O15 (BNBO) glasses were fabricated via the conventional melt- ...

  2. Investigation on microstructure and dielectric behaviour of (Ba0· 999 ...

    Indian Academy of Sciences (India)

    Ceramics of BaTiO3 co-doped with Gd and Cr at Ba-site was synthesized via solid-state reaction route. Surface morphology shows the increase in grain size with the increase of Cr-content below 3 mol%. The high value of in the synthesized samples is associated with space charge polarization and inhomogeneous ...

  3. Growth of single crystals of BaFe12O19 by solid state crystal growth

    International Nuclear Information System (INIS)

    Fisher, John G.; Sun, Hengyang; Kook, Young-Geun; Kim, Joon-Seong; Le, Phan Gia

    2016-01-01

    Single crystals of BaFe 12 O 19 are grown for the first time by solid state crystal growth. Seed crystals of BaFe 12 O 19 are buried in BaFe 12 O 19 +1 wt% BaCO 3 powder, which are then pressed into pellets containing the seed crystals. During sintering, single crystals of BaFe 12 O 19 up to ∼130 μm thick in the c-axis direction grow on the seed crystals by consuming grains from the surrounding polycrystalline matrix. Scanning electron microscopy-energy dispersive spectroscopy analysis shows that the single crystal and the surrounding polycrystalline matrix have the same chemical composition. Micro-Raman scattering shows the single crystal to have the BaFe 12 O 19 structure. The optimum growth temperature is found to be 1200 °C. The single crystal growth behavior is explained using the mixed control theory of grain growth. - Highlights: • Single crystals of BaFe 12 O 19 are grown by solid state crystal growth. • A single crystal up to ∼130 μm thick (c-axis direction) grows on the seed crystal. • The single crystal and surrounding ceramic matrix have similar composition. • Micro-Raman scattering shows the single crystal has the BaFe 12 O 19 structure.

  4. Studi On Oxidation State Of U In Ba2NdUO6

    International Nuclear Information System (INIS)

    Firman Windarto, Hendri

    1996-01-01

    Ba 2 NdUO 6 is not of the important compounds that is formed from a solidification process for high level liquid waste using super high temperature method Ba 2 NdUO 6 has ordered perovskite structure. The objective of this study is to investigate oxidation state of U in Ba 2 NdUO 6 . The properties of Ba 2 NdUO 6 were observed by using Faraday-type torsion magnetometer and X-ray Photoelectron Spectrometer (XPS). The magnetic susceptibility measured in the temperature range of 4K to room temperature showed that the Ba 2 NdUO 6 is paramagnetism that obeys the Curie-Weiss law. The effective moment of Ba 2 NdUO 6 is 3.04 μB. The results of xPs spectrum showed that the peaks of U4f for Ba 2 NdUO 6 appeared exactly between binding energy of UO 2 and UO 3 . It can be concluded that Ba 2 NdUO 6 has binding energy peaks corresponding to pentavalent uranium

  5. modified BiFeO3–BaTiO3

    Indian Academy of Sciences (India)

    based perovskite structures lead- free BiFeO3–BaTiO3 solid solutions are popularly studied due to the high Curie temperature (TC). It was reported that the BiFeO3–BaTiO3 system possessed high piezoelectric. ∗. Author for correspondence ...

  6. Photoluminescence properties of X5SiO4Cl6:Tb (X = Sr, Ba) green ...

    Indian Academy of Sciences (India)

    attracted more attention due to their potential applications ... materials were thoroughly mixed and ground in an agate mortar. ... Figure 2. Excitation spectra of Ba5SiO4Cl6:Tb3+ phosphor. spectrum of Tb3+ singly doped phosphor Ba5SiO4Cl6,.

  7. Oxygen perovskites of type Ba/sub 3/Bsup(III)RuIrO/sub 9/

    Energy Technology Data Exchange (ETDEWEB)

    Duerrschmidt, E; Kemmler-Sack, S [Tuebingen Univ. (Germany, F.R.). Lehrstuhl fuer Anorganische Chemie 2

    1980-11-01

    The black perovskites Ba/sub 3/Bsup(III)RuIrO/sub 9/ with Bsup(III) = La, Nd, Sm, Gd, Dy, Er, Yb, In, Sc are isotypic. They crystallize in a hexagonal BaTiO/sub 3/ structure (sequence (hcc)/sub 2/). The mean oxydation state of the noble metal ions is +4.5.

  8. The relationship of structure to superconductivity in the Pr-Ba-Cu-O system

    Science.gov (United States)

    Minseo, P.

    1994-05-01

    The relation of structure to lack of superconductivity in Pr-Ba-Cu-O was systematically investigated. First, the phase equilibria of this system was studied to find the processing parameters which maximize the cation-site ordering between Pr and Ba ions. Second, a comparative study between superconducting Nd-Ba-Cu-O and nonsuperconducting Pr-Ba-Cu-O was performed by forming solid-solution Nd-Pr-Ba-Cu-O. The relation between structure and superconductivity in Nd(1-x)Pr(x)Ba2Cu3O(7-delta) is investigated. T sub c decreases monotonically with increasing x and superconductivity disappears at around x = 0.3 to 0.4. T sub c is enhanced by 10 K when the sample is processed at an oxygen partial pressure (PO2) of 0.01 atm, followed by oxygenation at 450 C. Depression of T sub c as a function of x and PO2 is explained in terms of a charge-transfer model. It is suggested that destruction of superconductivity in the RE(1-x)Pr(x)Ba2Cu3O(7-delta) (RE=rare-earth) system can be viewed as disruption of four-fold planar coordinated Cu ions in the chain-site due to permanent occupation of extra Pr ions on Ba sites.

  9. CeF3(Ba) radiation hard scintillator for electromagnetic calorimeters

    International Nuclear Information System (INIS)

    Aseev, A.A.; Devitsin, E.G.; Kozlov, V.A.; Hovepyan, Yu.I.; Potashov, S.Yu.; Sokolovsky, K.A.; Uvarova, T.V.; Vasilchenko, V.G.

    1992-01-01

    The influence of divalent fluoride dopants BaF 2 , CaF 2 , SrF 2 on radiation and luminescent properties of CeF 3 crystal is studied. A high radiation hardness (>10 8 rad) has been obtained for CeF 3 crystals doped with BaF 2 . (orig.)

  10. Searches for low-mass Higgs and dark bosons at BaBar

    Energy Technology Data Exchange (ETDEWEB)

    Oberhof, Benjamin, E-mail: benjamin.oberhof@pi.infn.it [INFN sezione di Pisa and Universitá di Pisa, Polo Fibonacci - Edificio C, Largo B. Pontecorvo 3, 56125 - Pisa (Italy)

    2013-01-15

    We present BaBar latest results for the direct search of a light CP-odd Higgs boson using radiative decays of the ϒ(nS) (n=1,2,3) resonances in different final states. We also present the results for the search of a hidden sector gauge and Higgs bosons using the full BaBar datasample.

  11. Electrodeposition of BaCO3 coatings on stainless steel substrates ...

    Indian Academy of Sciences (India)

    Administrator

    Dedicated to the memory of the late Professor S K Rangarajan. *For correspondence. Electrodeposition of BaCO3 coatings on stainless steel substrates: Oriented growth ... orientation by an interfacial molecular recognition mechanism. BaCO3 has important applications in paint, ceramic, and paper industries. Also it is used ...

  12. Bifunctional properties of hydrothermal synthesized BaMF4 (M = Co, Ni and Zn

    Directory of Open Access Journals (Sweden)

    Farheen N. Sayed

    2013-07-01

    Full Text Available BaMF4 (M = Co, Ni and Zn samples having orthorhombic structure have been synthesized by a mild hydrothermal method and characterized by x-ray diffraction (XRD, magnetic and electrical measurements. Single phase formation of these compounds has been found to be dependent on various factors like reaction time, pH, temperature etc. All the samples showed ferroelectricity, which decreases with increase in temperature. BaMF4 (M = Co, Ni samples show 10-15 times more leakage current compared to that of BaZnF4 at higher applied field. Absence of multivalent ions in BaZnF4 can be the reason for its minimum leakage current. All the samples except, BaZnF4, exhibit weak room temperature ferromagnetism also.

  13. Surface structures and dielectric response of ultrafine BaTiO3 particles

    International Nuclear Information System (INIS)

    Jiang, B.; Peng, J.L.; Bursill, L.A.

    1998-01-01

    Characteristic differences are observed for the dielectric response and microstructures of BaTiO 3 nanoscale fine powders prepared using sol gel (SG) and steric acid gel (SAG) methods. The former exhibit a critical size below which there is no paraelectric/ferroelectric phase transition whereas BaTiO 3 prepared via the SAG route remained cubic for all conditions. Atomic resolution images of both varieties showed a high density of interesting surface steps and facets. Computer simulated images of surface structure models showed that the outer (100) surface was typically a BaO layer and that at corners and ledges the steps are typically finished with Ba+2 ions; i.e. the surfaces and steps are Ba-rich. Otherwise the surfaces were typically clean and free of amorphous layers. The relationship between the observed surfaces structures and theoretical models for size effects on the dielectric properties is discussed. (authors)

  14. The Preparation and Characterization of Tourmaline-Containing Functional Copolymer p (VST/MMA/BA

    Directory of Open Access Journals (Sweden)

    Yingmo Hu

    2018-01-01

    Full Text Available Tourmaline was modified with vinyl triethoxysilane containing double bond to prepare the polymerizable organic vinylsiliconoxyl tourmaline (VST and then copolymerized with methyl methacrylate (MMA and butyl acrylate (BA to produce the tourmaline-containing functional copolymer p (VST/MMA/BA. The structures and morphologies of VST and p (VST/MMA/BA copolymer were characterized by IR, SEM, and EDX. The experimental results indicated that tourmaline was introduced into the copolymer via surface modification and the tourmaline-containing functional copolymer was obtained by a copolymerization process with MMA and BA. The prepared p (VST/MMA/BA copolymer displayed excellent storage stabilities, high far-infrared radiation and negative ion releasing performances, and good mechanical properties.

  15. Magnetic and electrical properties in BaNiS2-type solid solutions

    International Nuclear Information System (INIS)

    Irizawa, Akinori; Yoshimura, Kazuyoshi; Kosuge, Koji

    2000-01-01

    The magnetic and electrical properties are reported in the new solid solutions BaCo 1-x Cu x S 2 and BaNi 1-x Fe x S 2 . Both compounds show spin-glass-like behavior, although the type of spin frustrations is different with each other. BaCo 1-x Cu x S 2 shows a competition type spin-glass behavior with reentrant phenomenon from antiferromagnetic to spin-glass at low temperatures. BaNi 1-x Fe x S 2 shows a dilute type spin-glass behavior together with super-paramagnetic properties. The temperature variation of 57 Fe Moessbauer spectra in BaNi 0.8 Fe 0.2 S 2 is explicable in a framework of cluster-glass. (author)

  16. Effect of Ba ions on the growth and mitochondrial metabolism of Mung bean seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Minton, G A; Wilson, R H

    1973-01-01

    The presence of high concentrations of BaCl/sub 2/ in vermiculite grown Mung bean (Phaseolus aureus) resulted in a reduction in shoot growth compared with plants grown in equivalent concentrations of CaCl/sub 2/. A high level of Ba ion was found in the mitochondria from plants grown at high Ba ion concentrations. Respiration rates of isolated mitochondria from plants grown at high levels of Ba were more rapid with all substrates tested, while the coupling parameters, including respiratory control with all substrates tested and ADP/O ratios with pyruvate-malate were partially reduced. These results are discussed as a possible mechanism of inhibition of plants grown in high-Ba soils. 12 references, 1 figure, 3 tables.

  17. Bound-bound transitions in the emission spectra of Ba+-He excimer

    Science.gov (United States)

    Moroshkin, P.; Kono, K.

    2016-05-01

    We present an experimental and theoretical study of the emission and absorption spectra of the Ba+ ions and Ba+*He excimer quasimolecules in the cryogenic Ba-He plasma. We observe several spectral features in the emission spectrum, which we assign to the electronic transitions between bound states of the excimer correlating to the 6 2P3 /2 and 5 2D3 /2 ,5 /2 states of Ba+. The resulting Ba+(5 2DJ) He is a metastable electronically excited complex with orbital angular momentum L =2 , thus expanding the family of known metal-helium quasimolecules. It might be suitable for high-resolution spectroscopic studies and for the search for new polyatomic exciplex structures.

  18. Mechanical properties of Nd-Ba-Cu-O bulk superconductors

    International Nuclear Information System (INIS)

    Matsui, Motohide; Sakai, Naomichi; Murakami, Masato; Osamura, Kozo

    2003-01-01

    We investigated the effects of Nd422 and Ag particles on the mechanical properties in Nd-Ba-Cu-O bulk superconductors. Both Nd422 and Ag particles were effective in decreasing the amount of microcracks running along the c direction. In the case of Nd422, however, excessive Nd422 addition enhanced the crack propagation, resulting in the degradation of mechanical strength. In the case of Ag addition, the beneficial effect of its ductile mechanical property was not observed. This was due to a relatively large size of Ag particles and low interfacial strength between Ag and Nd123 matrix. It was remarkable that the Weibull coefficient of the sample with Ag 2 O addition exceeded 13, which is reliable enough for practical engineering applications

  19. Radiation damage in BaF2 crystals

    International Nuclear Information System (INIS)

    Woody, C.L.; Kierstead, J.A.; Levy, P.W.; Stoll, S.

    1991-01-01

    The effects of radiation damage and recovery have been studied in BaF 2 crystals exposed to 60 Co radiation. The change in optical transmission and scintillation light output have been measured as a function of dose up to 4.7 x 10 6 rad. Although some crystals exhibit a small change in transmission, a greater change in scintillation light output is observed. Several 25 cm long crystals whichhave been irradiated show large changes in both transmission and light output. Recovery from radiation damage has been studied as a function of time and exposure to UV light. A long lived radiation induced phosphorescence has been observed in all irradiated samples which is distinct from the standard fast and slow scintillation emissions. The emission spectrum of the phosphorescence has been measured and shown a peakat ∼330 nm, near the region of the slow scintillation component. Results are given on the dependence of the decay time of the phosphorescence with dose

  20. The New BaBar Data Reconstruction Control System

    International Nuclear Information System (INIS)

    Ceseracciu, Antonio

    2003-01-01

    The BaBar experiment is characterized by extremely high luminosity, a complex detector, and a huge data volume, with increasing requirements each year. To fulfill these requirements a new control system has been designed and developed for the offline data reconstruction system. The new control system described in this paper provides the performance and flexibility needed to manage a large number of small computing farms, and takes full benefit of OO design. The infrastructure is well isolated from the processing layer, it is generic and flexible, based on a light framework providing message passing and cooperative multitasking. The system is actively distributed, enforces the separation between different processing tiers by using different naming domains, and glues them together by dedicated brokers. It provides a powerful Finite State Machine framework to describe custom processing models in a simple regular language. This paper describes this new control system, currently in use at SLAC and Padova on ∼450 CPUs organized in 12 farms

  1. Obtention and applications of Cs-Ba-137m generators

    International Nuclear Information System (INIS)

    Karpeles, Alfredo; Rivero, Mario.

    1974-11-01

    The preparation of a sterile Ba-137m generator and the properties of the product eluted with different solutions are described. The developed generator uses a very high stable inorganic ion exchanger: hexacianoferrate deposited on small steel turnings. The high void volume of the absorbing bed allows elution velocities of >10 ml/min and elution yields over 70%. Elution curves are presented and purities of the product are given for following elutrians: diluted hydrochloric acid and sodium chloride solutions EDTA and calcium levulinate solutions. The product can be obtained sterile and useful for direct administration to patients for diagnostic studies in Nuclear Medicine. Applications in medical dynamic studies and radio-chemistry teaching are given. (author)

  2. The BaBar experiment's distributed computing model

    International Nuclear Information System (INIS)

    Boutigny, D.

    2001-01-01

    In order to face the expected increase in statistics between now and 2005, the BaBar experiment at SLAC is evolving its computing model toward a distributed multitier system. It is foreseen that data will be spread among Tier-A centers and deleted from the SLAC center. A uniform computing environment is being deployed in the centers, the network bandwidth is continuously increased and data distribution tools has been designed in order to reach a transfer rate of ∼100 TB of data per year. In parallel, smaller Tier-B and C sites receive subsets of data, presently in Kanga-ROOT format and later in Objectivity format. GRID tools will be used for remote job submission

  3. Raman study of Ba-doped ceria nanopowders

    Directory of Open Access Journals (Sweden)

    Radović M.

    2007-01-01

    Full Text Available A series of Ce1-xBaxO2-y (5£x£0.20 nanometric powders were synthesized by selfpropagating room temperature synthesis. XRD and Raman scattering measurements were used to characterize the samples at room temperature. All the samples are solid solutions with fluorite type structure with an average crystallite size about 5 nm. The redshift and asymmetric broadening of the Raman F2g mode can be well explained with combined confinement and strain effects because of the nanocrystalline powders nature. The appearance of the additional peaks at ~ 560 cm-1 and ~ 600 cm-1, are attributed to extrinsic and intrinsic O2- vacancies in ceria lattice. Raman spectra of temperature treated Ce0.80Ba0.20O2-d sample revealed the instability of this system.

  4. Critical state in the Y-Ba-Cu-O ceramics

    International Nuclear Information System (INIS)

    Artemov, A.N.; Grishin, A.M.; Korenivskii, V.N.; Ulyanov, A.N.; Khokhlov, V.A.

    1990-01-01

    This paper reports on the temperature and field dependences of the Y-Ba-Cu-O ceramics susceptibility studied both experimentally and theoretically. These dependence have been used to reconstruct the temperature dependence of the critical current (j c (T) = j c (O)(1 - T/T c1 ) 3/2 , J c (O) = 340 A/cm 2 , T c1 = 94.6 K) and the distribution of the granules with respect to the superconducting transition temperature (with the maximum at T c2 = 95.3 K and ΔT = 1.1 K). Within the critical state concept diamagnetic response of the granular superconductors at fundamental and multiple frequencies has been calculated. The calculation results are in good agreement with the experimentally obtained susceptibility dependences and explain the different dependences of the diamagnetic response on the magnitude of the d.c. field and the amplitude of a.c. field

  5. Microwave ionization and excitation of Ba Rydberg atoms

    International Nuclear Information System (INIS)

    Eichmann, U.; Dexter, J.L.; Xu, E.Y.; Gallagher, T.F.

    1989-01-01

    We have investigated ionization and excitation of the Ba 6sn s 1 S 0 and 6snd 1,3 D 2 series in strong microwave fields. The observed microwave ionization threshold fields, scaling as 0.28 n -5 , and the state mixing fields cannot be completely explained in terms of a single cycle Landau-Zener model. However, by taking into account multiphoton resonant transitions driven by many cycles of the microwave field we have been able to interpret the data. In particular multi-photon transitions have been found to be responsible for apparent resonance structures and for the unexpectedly low mixing fields. Not surprisingly, doubly excited valence states introduce irregularities into both the microwave ionization and the state mixing field values. (orig.)

  6. The BaBar Experiment's Distributed Computing Model

    International Nuclear Information System (INIS)

    Gowdy, Stephen J.

    2002-01-01

    In order to face the expected increase in statistics between now and 2005, the BaBar experiment at SLAC is evolving its computing model toward a distributed multi-tier system. It is foreseen that data will be spread among Tier-A centers and deleted from the SLAC center. A uniform computing environment is being deployed in the centers, the network bandwidth is continuously increased and data distribution tools has been designed in order to reach a transfer rate of ∼100 TB of data per year. In parallel, smaller Tier-B and C sites receive subsets of data, presently in Kanga-ROOT[1] format and later in Objectivity[2] format. GRID tools will be used for remote job submission

  7. Effect of iron doping on Y-Ba-Cu-O

    International Nuclear Information System (INIS)

    Abd Halim Shaari; Mansor Hashim; Sidek Hj Abd Aziz; Laily Rafiah Abdullah

    1991-01-01

    Study on the effect of iron doping at different values of doping percentage (0.00< x<0.06) and hence the influence of magnetic iron on Y-Ba-Cu-O superconductor has been carried out. The conventional technique of sintering is used in preparing the ceramic materials. The crystal structure and their lattice parameters are determined from X-ray diffraction measurements. Observation on the dependence of resistance on temperature is made between room temperature to the boiling point of liquid nitrogen, using four-probe techniques. Magnetisation properties namely the Meissner Effect is also observed by levitating a small piece of permanent magnet on the cooled sample. The X-ray diffraction data show that the phase transitions have been observed; from orthorhombic to tetragonal when the iron doping exceeded ∼0.02. Transition temperature, Tc decrease from ∼87.7K to ∼83K. Meissner Effect is observed for sample doped up to 2% only

  8. Strain effect on the phase diagram of Ba-122

    Energy Technology Data Exchange (ETDEWEB)

    Iida, Kazumasa [IFW Dresden (Germany); Nagoya University (Japan); Grinenko, Vadim; Kurth, Fritz; Efremov, Dmitriy; Drechsler, Stefan-Ludwig; Engelmann, Jan; Aswartham, Saicharan; Wurmehl, Sabine; Moench, Ingolf; Huehne, Ruben [IFW Dresden (Germany); Langer, Marco; Erbe, Manuela; Haenisch, Jens; Holzapfel, Bernhard [IFW Dresden (Germany); Karlsruhe Institute of Technology (KIT) (Germany); Ichinose, Ataru; Tsukada, Ichiro [Central Research Institute of Electric Power Industry, Nagasaka (Japan); Ahrens, Eike [TU Dresden (Germany); Ikuta, Hiroshi [Nagoya University (Japan)

    2015-07-01

    Thin films offer a possibility for tuning superconducting (SC) properties without external pressure or chemical doping. In-plane strain controls the Neel temperature of the antiferromagnetic (AF) transition and the SC transition temperature or even induce superconductivity in the parent compound. We studied the electronic and magnetic properties of Co, Ru, and P doped Ba-122 thin films in different strain states. We have found that the strain shifts nearly rigidly the whole phase diagram including the AF region and the SC dome in the direction of higher or lower substitution levels depending on the direction of strain (i.e. compressive or tensile). In particular, we found that the strain affects the band structure similarly as Co doping despite that the crystal structure changes differently. As a result tensile or compressive strain acts as additional el or h doping, respectively.

  9. Thermoelectric transport properties of BaBiTe{sub 3}-based materials

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yiming; Zhao, Li-Dong, E-mail: zhaolidong@buaa.edu.cn

    2017-05-15

    BaBiTe{sub 3}, a material with low thermal conductivity, is an inferior thermoelectric material due to the poor electrical properties originated from its narrow band gap. We choose two types of dopants, K and La, trying to optimize its electrical transport properties. The minority carriers, which harm the Seebeck coefficient in this system, are suppressed by La doping. With the increase of both electrical conductivity and Seebeck coefficient, the power factor of 3% La doped BaBiTe{sub 3} reaches 3.7 μW cm{sup −1} K{sup −2} which increased by 40% from undoped BaBiTe{sub 3}. Besides high power factor, the thermal conductivity is also reduced in it. Eventually, a high ZT value, 0.25 at 473 K, for n-type BaBiTe{sub 3} is achieved in 3% La doped BaBiTe{sub 3}. - Graphical abstract: BaBiTe{sub 3} possesses a low thermal conductivity. However, it is an inferior thermoelectric material due to the poor electrical properties originated from its narrow band gap. A high ZT value of 0.25 at 473 K for n-type BaBiTe{sub 3} can be achieved through optimizing electrical transport properties via La doping. - Highlights: • BaBiTe{sub 3} is an analogue of these promising thermoelectric materials: such as CsBi{sub 4}Te{sub 6} and K{sub 2}Bi{sub 8}Se{sub 13}, etc. • BaBiTe{sub 3} possesses a low thermal conductivity. • La is an effective dopant to enhance electrical transport properties. • A high ZT value of 0.25 at 473 K can be achieved in n-type La-doped BaBiTe{sub 3}.

  10. Analysis of oxygen binding-energy variations for BaO on W

    Science.gov (United States)

    Haas, G. A.; Shih, A.; Mueller, D.; Thomas, R. E.

    Interatomic Auger analyses have been made of different forms of BaO layers on W substrates. Variations in Auger spectroscopy energies of the Ba4dBa5pO2p interatomic Auger transition were found to be largely governed by the O2p binding energy of the BaO adsorbate. This was illustrated by comparing results of the Auger data values with values derived from O2p binding energies using ultraviolet photoelectron spectroscopy. Very good agreement was observed not only for the W substrate but also for the W substrate which showed two oxygen-induced electronics state. Variations in binding energy were noted for different states of BaO lattice formation and for different amounts of oxidation, ranging from the transition of Ba to BaO and continuing to the BaO 2 stoichiometry and beyond. Effects were also reported for adsorbate alignment and thermal activation (i.e., reduction) of the oxidized state. An empirical relationship was found suggesting that the more tightly bound the O2p states of the BaO adsorbate were, the lower its work function would be. This link between binding energy and work function was observed to be valid not only for cases of poisoning by oxidation, but held as well during reactivation by the subsequent reduction of the oxide. In addition, this relationship also appeared to predict the low work function obtained through the introduction of substances such as Sc to the BaO-W system. Possible qualitative reasons which might contribute to this are discussed in terms of enhanced dipole effects and shifts in band structure.

  11. Radiation dosimetry using nano-BaSO{sub 4}:Eu

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, A.; Sharma R, K. [University of Delhi, Department of Physics, Sri Venkateswara College, Benito Juarez Road, Dhaula Kuan, 110021 New Delhi (India); Bahl, S.; Kumar, P. [Medical Physics Unit, IRCH, AIIMS, 110029 New Delhi (India); Pal L, S., E-mail: apandey@svc.ac.in [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, 110067 New Delhi (India)

    2015-10-15

    Nanocrystalline barium sulfate doped with europium (BaSO{sub 4}:Eu) was successfully prepared by the chemical co-precipitation technique and its thermoluminescence (Tl) dosimetry characteristics were studied for gamma radiation. Initially the dopant (Eu) concentration was varied, starting from 0.05 mol % to up to 1.00 mol %, and it was found that the nano phosphor BaSO{sub 4}:Eu with the dopant concentration of 0.2 mol % had the highest sensitivity within the given lot. The nano phosphor was also optimized for its annealing temperature in order to obtain the best results and was thereafter tested for its reusability and fading features. Further the nano phosphor was compared with the commercially available standard Tl dosimeter material LiF:Mg,Ti (popularly referred to as TLD-100) and it was found that the nano phosphor not only had a higher Tl sensitivity compared to the standard material over a wide range of doses but also had a Tl response which was linear even beyond the dose of 1 kGy. Linearity in Tl response to up to such high doses (∼1 kGy) is typical of nanocrystalline Tl phosphors. All the samples were irradiated by Co-60 source (having 1.25 MeV average energy) of gamma radiation. In order to test the energy independence of the nano phosphor (an important characteristic of an ideal Tl dosimeter) further studies are being carried out to examine the response of the nano phosphor to ionizing radiations of different energies. (Author)

  12. Separation of Sr from Ca, Ba and Ra by means of Ca(OH)2 and Ba(Ra)Cl2 or Ba(Ra)SO4 for the determination of radiostrontium

    DEFF Research Database (Denmark)

    Chen, Q.J.; Hou, Xiaolin; Yu, Y.X.

    2002-01-01

    be completed. The new separation procedure has been successfully used for the determination of Sr-90 in samples with high Ca content, such as 451 of seawater and 2001 of drinking water. The analytical quality of the results is comparable to that of the traditional method using fuming nitric acid and BaCrO4......A simple procedure is developed to separate Sr from a large amount of Ca, which relies on the insolubility of Ca(OH)(2) in alkaline solution. Calcium is quantitatively separated from Sr and more than 95% of Sr is recovered from a sample with as much as 50 g of Ca and a Ca/Sr mole ratio of 250....... A new procedure for the separation of Sr from Ba and Ra is also investigated, which is based on the difference in solubility of the chlorides of Sr, Ba and Ra in HCl media. In 9.5 mol 1(-1) HCl or 7.5 mol 1(-1) HCl-10% acetone media, >97% of Ba and Ra can be removed by Ba(Ra)Cl-2 precipitation, and >94...

  13. Decrease in electrical contact resistance of Sb-doped n+-BaSi2 layers and spectral response of an Sb-doped n+-BaSi2/undoped BaSi2 structure for solar cells

    Science.gov (United States)

    Kodama, Komomo; Takabe, Ryota; Yachi, Suguru; Toko, Kaoru; Suemasu, Takashi

    2018-03-01

    We investigated how the electron concentration n in a 300-nm-thick Sb-doped n+-BaSi2 layer grown by molecular beam epitaxy affected the contact resistance R C to surface electrodes (Al, indium-tin-oxide). As the n of n-BaSi2 increased, R C decreased and reached a minimum of 0.019 Ω cm2 at n = 2.4 × 1018 cm-3 for the Al electrodes. This value was more than 1 order of magnitude smaller than that obtained for Al/B-doped p-BaSi2. We believe that this significant decrease in R C came from Sb segregation. Furthermore, the internal quantum efficiency (IQE) spectrum was evaluated for an Sb-doped n+-BaSi2 (20 nm)/undoped BaSi2 (500 nm)/n+-Si(111) structure. Its IQE reached as high as ˜50% over a wide wavelength range under a small bias voltage of 0.1 V applied between the top and bottom electrodes.

  14. The new barium zinc mercurides Ba3ZnHg10 and BaZn0.6Hg3.4 – Synthesis, crystal and electronic structure

    International Nuclear Information System (INIS)

    Schwarz, Michael; Wendorff, Marco; Röhr, Caroline

    2012-01-01

    The title compounds Ba 3 ZnHg 10 and BaZn 0.6 Hg 3.4 were synthesized from stoichiometric ratios of the elements in Ta crucibles. Their crystal structures, which both represent new structure types, have been determined using single crystal X-ray data. The structure of Ba 3 ZnHg 10 (orthorhombic, oP28, space group Pmmn, a=701.2(3), b=1706.9(8), c=627.3(3)pm, Z=2, R1=0.0657) contains folded 4 4 Hg nets, where the meshes form the bases of flat rectangular pyramids resembling the structure of BaAl 4 . The flat pyramids are connected via Hg–Zn/Hg bonds, leaving large channels at the folds, in which Ba(1) and Hg(2) atoms alternate. Whereas the remaining Hg/Zn atoms form a covalent 3D network of three- to five-bonded atoms with short M–M distances (273–301 pm; CN 9–11), the Hg(2) atoms in the channels adopt a comparatively large coordination number of 12 and increased distances (317–348 pm) to their Zn/Hg neighbours. In the structure of BaZn 0.6 Hg 3.4 (cubic, cI320, space group I4 ¯ 3d, a=2025.50(7) pm, Z=64, R1=0.0440), with a chemical composition not much different from that of Ba 3 ZnHg 10 , the Zn/Hg atoms of the mixed positions M(1/2) are arranged in an slightly distorted primitive cubic lattice with a 4×4×4 subcell relation to the unit cell. The 24 of the originating 64 cubes contain planar cis tetramers Hg(5,6) 4 with Hg in a nearly trigonal planar or tetrahedral coordination. In another 24 of the small cubes, two opposing faces are decorated by Hg(3,4) 2 dumbbells, two by Ba(2) atoms respectively. The third type of small cubes are centered by Ba(1) atoms only. The complex 3D polyanionic Hg/Zn network thus formed is compared with the Hg partial structure in Rb 3 Hg 20 applying a group-subgroup relation. Despite their different overall structures, the connectivity of the negatively charged Hg atoms, the rather metallic Zn bonding characteristic (as obtained from FP-LAPW band structure calculations) and the coordination number of 16 for all Ba cations

  15. The Impact of Different Permissible Exposure Limits on Hearing Threshold Levels Beyond 25 dBA.

    Science.gov (United States)

    Sayapathi, Balachandar S; Su, Anselm Ting; Koh, David

    2014-10-01

    Development of noise-induced hearing loss is reliant on a few factors such as frequency, intensity, and duration of noise exposure. The occurrence of this occupational malady has doubled from 120 million to 250 million in a decade. Countries such as Malaysia, India, and the US have adopted 90 dBA as the permissible exposure limit. According to the US Occupational Safety and Health Administration (OSHA), the exposure limit for noise is 90 dBA, while that of the US National Institute of Occupational Safety and Health (NIOSH) is 85 dBA for 8 hours of noise exposure. This study aimed to assess the development of hearing threshold levels beyond 25 dBA on adoption of 85 dBA as the permissible exposure limit compared to 90 dBA. This is an intervention study done on two automobile factories. There were 203 employees exposed to noise levels beyond the action level. Hearing protection devices were distributed to reduce noise levels to a level between the permissible exposure limit and action level. The permissible exposure limits were 90 and 85 dBA in factories 1 and 2, respectively, while the action levels were 85 and 80 dBA, respectively. The hearing threshold levels of participants were measured at baseline and at first month of postshift exposure of noise. The outcome was measured by a manual audiometer. McNemar and chi-square tests were used in the statistical analysis. We found that hearing threshold levels of more than 25 dBA has changed significantly from pre-intervention to post-intervention among participants from both factories (3000 Hz for the right ear and 2000 Hz for the left ear). There was a statistically significant association between participants at 3000 Hz on the right ear at 'deteriorated' level ( χ² (1) = 4.08, φ = - 0.142, P = 0.043), whereas there was worsening of hearing threshold beyond 25 dBA among those embraced 90 dBA. The adoption of 85 dBA as the permissible exposure limit has preserved hearing threshold level among participants at 3000 Hz

  16. Improvement of β-phase crystal formation in a BaTiO3-modified PVDF membrane

    Science.gov (United States)

    Lin, SHEN; Lei, GONG; Shuhua, CHEN; Shiping, ZHAN; Cheng, ZHANG; Tao, SHAO

    2018-04-01

    In this paper, low temperature plasma is used to modify the surface of barium titanate (BaTiO3) nanoparticles in order to enhance the interfacial compatibility between ferroelectric poly(vinylidene fluoride) (PVDF) and BaTiO3 nanoparticles. The results demonstrate that oxygenic groups are successfully attached to the BaTiO3 surface, and the quantity of the functional groups increases with the treatment voltage. Furthermore, the effect of modified BaTiO3 nanoparticles on the morphology and crystal structure of the PVDF/BaTiO3 membrane is investigated. The results reveal that the dispersion of BaTiO3 nanoparticles in the PVDF matrix was greatly improved due to the modification of the BaTiO3 nanoparticles by air plasma. It is worth noting that the formation of a β-phase in a PVDF/modified BaTiO3 membrane is observably promoted, which results from the strong interaction between PVDF chains and oxygenic groups fixed on the BaTiO3 surface and the better dispersion of BaTiO3 nanoparticles in the PVDF matrix. Besides, the PVDF/modified BaTiO3 membrane at the treatment voltage of 24 kV exhibits a lower water contact angle (≈68.4°) compared with the unmodified one (≈86.7°). Meanwhile, the dielectric constant of PVDF/BaTiO3 nanocomposites increases with the increase of working voltage.

  17. Electrochemical performance of BaSnO3 anode material for lithium-ion battery prepared by molten salt method

    CSIR Research Space (South Africa)

    Nithyadharseni, P

    2016-01-01

    Full Text Available Perovskite-like structure BaSnO(sub3) ceramic oxide has been prepared by low temperature molten salt method using KOH as a flux and Ba(OH)(sub2) and BaCl(sub2) as precursors. The as-prepared compounds were characterized by various techniques...

  18. Perovskite phases in the systems AO-SE/sub 2/O/sub 3/-UO/sub 2,x/ with A=alkaline earth metal and SE=rare earths, La, and Y. VII. The systems Ba/sub 2/CaUO/sub 6/-Ba/sub 2/Gd/sub 0. 67/UO/sub 6/ and Ba/sub 2/CaUO/sub 6/-Ba/sub 2/Y/sub 0. 67/UO/sub 6/

    Energy Technology Data Exchange (ETDEWEB)

    Kemmler-Sack, S; Seemann, I; Schittenhelm, H J [Tuebingen Univ. (F.R. Germany). Institut fuer Anorganische Chemie

    1976-05-01

    The ordered perovskite Ba/sub 2/CaUO/sub 6/ forms a solid solution series with Ba/sub 2/Gdsub(0.67)UO/sub 6/ and Ba/sub 2/Ysub(0.67)UO/sub 6/, respectively. The deviations from the ideal behaviour are studied by X-ray, diffuse reflectance and vibrational methods.

  19. Perovskite phases in the systems AO-SE/sub 2/O/sub 3/-UO/sub 2,x/ with A=alkaline earth metal and SE=rare earths, La, and Y. IX. The systems Ba/sub 2/SrUO/sub 6/-Ba/sub 2/Gd/sub 0. 67/UO/sub 6/ and Ba/sub 2/SrUO/sub 6/-Ba/sub 2/Y/sub 0. 67/UO/sub 6/

    Energy Technology Data Exchange (ETDEWEB)

    Kemmler-Sack, S; Seemann, I [Tuebingen Univ. (F.R. Germany). Inst. fuer Anorganische Chemie I

    1976-07-01

    The ordered perovskite Ba/sub 2/SrUO/sub 6/ forms a solid solution series with Ba/sub 2/Gdsub(0.67)UO/sub 6/ and Ba/sub 2/Ysub(0.67)UO/sub 6/ respectively. The deviations from the ideal behaviour are studied by X-ray, diffuse reflectance and vibrational methods.

  20. Application of NAA and BA in chemical thinning of some commercial apple cultivars

    Directory of Open Access Journals (Sweden)

    Šebek Gordana

    2015-01-01

    Full Text Available This paper presents the fruit thinning response of some commercial apple cultivars to NAA and BA plant regulators. The experiment was designed to evaluate NAA applied separately at three concentrations - 13.2 ppm, 17.82 ppm and 26.73 ppm, and BA + NAA combinations (BA - 60 ppm, 100 ppm, 120 ppm or 140 ppm + NAA 4.29 ppm for thinning the assessed apple cultivars. All treatments with NAA and BA + NAA adequately thinned 'McIntosh' and 'Jonathan', whereas the application of NAA 17.82 ppm and 26.73 ppm and the combined treatment BA 140 ppm+ NAA 4.29 ppm were effective fruit thinners for 'Prima'. In terms of the average fruit weight, number of fruits categorized as large (> 75 mm or > 65 mm, and number of fruit per trunk cross-sectional area, the treatment BA 140 ppm + NAA 4.29 ppm was most effective on 'McIntosh' and 'Prima', whereas BA 100 ppm + NAA 4.29 ppm had the best effect on 'Jonathan'.

  1. Wet routes of high purity BaTiO3 nanopowders

    International Nuclear Information System (INIS)

    Wang Liqiu; Liu Liang; Xue Dongfeng; Kang Hongmin; Liu Changhou

    2007-01-01

    High purity BaTiO 3 nanopowders were prepared in wet routes through stearic acid gel (SAG) and acetic acid gel (AAG) techniques, respectively. BaTiO 3 samples were characterized by X-ray diffraction, transmission electron microscope, Fourier transform infrared spectrometry, X-ray fluorescence spectrometry, and thermal gravimetric analysis. The present results indicate that both methods have a similar reaction process during calcination, while BaTiO 3 crystallites were initially formed at 550 deg. C by SAG and 800 deg. C by AAG. Both methods could produce BaTiO 3 powders with a cubic perovskite structure, while they had different grain size distributions within 25-50 nm for SAG and 50-80 nm for AAG. BaTiO 3 samples prepared by SAG had a lower agglomeration than those by AAG. SAG has shown many distinctive advantages in the preparation of high purity BaTiO 3 nanopowders, without Ba and Ti losses and hazardous wastes

  2. Nuclear sub-structure in 112–122Ba nuclei within relativistic mean field theory

    International Nuclear Information System (INIS)

    Bhuyan, M.; Patra, S.K.; Arumugam, P.; Gupta, Raj K.

    2011-01-01

    Working within the framework of relativistic mean field theory, we study for the first time the clustering structure (nuclear sub-structure) of 112–122 Ba nuclei in an axially deformed cylindrical coordinate. We calculate the individual neutrons and protons density distributions for Ba-isotopes. From the analysis of the clustering configurations in total (neutrons-plus-protons) density distributions for various shapes of both the ground and excited states, we find different sub-structures inside the Ba nuclei considered here. The important step, carried out here for the first time, is the counting of number of protons and neutrons present in the clustering region(s). 12 C is shown to constitute the cluster configuration in prolate-deformed ground-states of 112–116 Ba and oblate-deformed first excited states of 118–122 Ba nuclei. Presence of other lighter clusters such as 2 H, 3 H and nuclei in the neighborhood of N = Z, 14 N, 34–36 Cl, 36 Ar and 42 Ca are also indicated in the ground and excited states of these nuclei. Cases with no cluster configuration are shown for 112–116 Ba in their first and second excited states. All these results are of interest for the observed intermediate-mass-fragments and fusion–fission processes, and the so far unobserved evaporation residues from the decaying Ba* compound nuclei formed in heavy ion reactions. (author)

  3. Synthesis, Crystal Structure, and Chemical-Bonding Analysis of BaZn(NCN2

    Directory of Open Access Journals (Sweden)

    Alex J. Corkett

    2017-12-01

    Full Text Available The ternary carbodiimide BaZn(NCN2 was prepared by a solid-state metathesis reaction between BaF2, ZnF2, and Li2NCN in a 1:1:2 molar ratio, and its crystal structure was determined from Rietveld refinement of X-ray data. BaZn(NCN2 represents the aristotype of the LiBa2Al(NCN4 structure which is unique to carbodiimide/cyanamide chemistry and is well regarded as being constructed from ZnN4 tetrahedra, sharing edges and vertices through NCN2− units to form corrugated layers with Ba2+ in the interlayer voids. Structural anomalies in the shape of the cyanamide units are addressed via IR spectrometry and DFT calculations, which suggest the presence of slightly bent N=C=N2− carbodiimide units with C2v symmetry. Moreover, chemical-bonding analysis within the framework of crystal orbital Hamilton population (COHP reveals striking similarities between the bonding interactions in BaZn(NCN2 and SrZn(NCN2 despite their contrasting crystal structures. BaZn(NCN2 is only the second example of a ternary post-transition metal carbodiimide, and its realization paves the way for the preparation of analogues featuring divalent transition metals at the tetrahedral Zn2+ site.

  4. Carbon-14 immobilization via the CO2-Ba(OH)2 hydrate gas-solid reaction

    International Nuclear Information System (INIS)

    Haag, G.L.

    1981-08-01

    For the treatment of an air-based off-gas stream, the use of packed beds of Ba(OH) 2 .8H 2 O flakes to remove CO 2 has been demonstrated. However, the operating conditions must be maintained between certain upper and lower limits with respect to the partial pressure of water. If the water vapor pressure in the gas is less than the dissociation vapor pressure of Ba(OH) 2 .8H 2 O, the bed will deactivate. If the vapor pressure is considerably greater, pressure drop problems will increase with increaseing humidity as the particles curl and degrade. Results have indicted that when operated in the proper regime, the bulk of the increase in pressure drop results from the conversion of Ba(OH) 2 .8H 2 O to BaCO 3 and not from the hydration of the commercial Ba(OH) 2 .8H 2 O (i.e., Ba(OH) 2 .7.50H 2 O) to Ba(OH) 2 .8H 2 O

  5. Left cytoarchitectonic BA 44 processes syntactic gender violations in determiner phrases.

    Science.gov (United States)

    Heim, Stefan; van Ermingen, Muna; Huber, Walter; Amunts, Katrin

    2010-10-01

    Recent neuroimaging studies make contradictory predictions about the involvement of left Brodmann's area (BA) 44 in processing local syntactic violations in determiner phrases (DPs). Some studies suggest a role for BA 44 in detecting local syntactic violations, whereas others attribute this function to the left premotor cortex. Therefore, the present event-related functional magnetic resonance imaging (fMRI) study investigated whether left-cytoarchitectonic BA 44 was activated when German DPs involving syntactic gender violations were compared with correct DPs (correct: 'der Baum'-the[masculine] tree[masculine]; violated: 'das Baum'--the[neuter] tree[masculine]). Grammaticality judgements were made for both visual and auditory DPs to be able to generalize the results across modalities. Grammaticality judgements involved, among others, left BA 44 and left BA 6 in the premotor cortex for visual and auditory stimuli. Most importantly, activation in left BA 44 was consistently higher for violated than for correct DPs. This finding was behaviourally corroborated by longer reaction times for violated versus correct DPs. Additional brain regions, showing the same effect, included left premotor cortex, supplementary motor area, right middle and superior frontal cortex, and left cerebellum. Based on earlier findings from the literature, the results indicate the involvement of left BA 44 in processing local syntactic violations when these include morphological features, whereas left premotor cortex seems crucial for the detection of local word category violations. © 2010 Wiley-Liss, Inc.

  6. Dynamics of photoexcited Ba{sup +} cations in {sup 4}He nanodroplets

    Energy Technology Data Exchange (ETDEWEB)

    Leal, Antonio; Pi, Martí [Departament ECM, Facultat de Física, and IN" 2UB, Universitat de Barcelona, Diagonal 645, 08028 Barcelona (Spain); Zhang, Xiaohang; Drabbels, Marcel [Laboratoire de Chimie Physique Moléculaire, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne (Switzerland); Barranco, Manuel [Departament ECM, Facultat de Física, and IN" 2UB, Universitat de Barcelona, Diagonal 645, 08028 Barcelona (Spain); Laboratoire des Collisions, Agrégats, Réactivité, IRSAMC, UMR 5589, CNRS et Université Paul Sabatier-Toulouse 3, 118 route de Narbonne, F-31062 Toulouse Cedex 09 (France); Cargnoni, Fausto [Istituto di Scienze e Tecnologie Molecolari (ISTM), Consiglio Nazionale delle Ricerche, via Golgi 19, 20133 Milano (Italy); Hernando, Alberto [Social Thermodynamics Applied Research (SThAR), EPFL Innovation Park, Bâtiment C, CH-1015 Lausanne (Switzerland); Mateo, David [Department of Chemistry and Biochemistry, California State University at Northridge, Northridge, California 91330 (United States); Mella, Massimo [Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell’Insubria, via Valleggio 11, 22100 Como (Italy)

    2016-03-07

    We present a joint experimental and theoretical study on the desolvation of Ba{sup +} cations in {sup 4}He nanodroplets excited via the 6p ← 6s transition. The experiments reveal an efficient desolvation process yielding mainly bare Ba{sup +} cations and Ba{sup +}He{sub n} exciplexes with n = 1 and 2. The speed distributions of the ions are well described by Maxwell-Boltzmann distributions with temperatures ranging from 60 to 178 K depending on the excitation frequency and Ba{sup +} He{sub n} exciplex size. These results have been analyzed by calculations based on a time-dependent density functional description for the helium droplet combined with classical dynamics for the Ba{sup +}. In agreement with experiment, the calculations reveal the dynamical formation of exciplexes following excitation of the Ba{sup +} cation. In contrast to experimental observation, the calculations do not reveal desolvation of excited Ba{sup +} cations or exciplexes, even when relaxation pathways to lower lying states are included.

  7. Carbon-14 immobilization via the CO2-Ba(OH)2 hydrate gas-solid reaction

    International Nuclear Information System (INIS)

    Haag, G.L.

    1980-01-01

    Although no restrictions have been placed on the release of carbon-14, it has been identified as a potential health hazard due to the ease in which it may be assimilated into the biosphere. The intent of the Carbon-14 Immobilization Program, funded through the Airborne Waste Program Management Office, is to develop and demonstrate a novel process for restricting off-gas releases of carbon-14 from various nuclear facilities. The process utilizes the CO 2 -Ba(OH) 2 hydrate gas-solid reaction to directly remove and immobilize carbon-14. The reaction product, BaCO 3 , possesses both the thermal and chemical stability desired for long-term waste disposal. The process is capable of providing decontamination factors in excess of 1000 and reactant utilization of greater than 99% in the treatment of high volumetric, airlike (330 ppM CO 2 ) gas streams. For the treatment of an air-based off-gas stream, the use of packed beds of Ba(OH) 2 .8H 2 O flakes to remove CO 2 has been demonstrated. However, the operating conditions must be maintained between certain upper and lower limits with respect to the partial pressure of water. If the water vapor pressure in the gas is less than the dissociation vapor pressure of Ba(OH) 2 .8H 2 O, the bed will deactivate. If the vapor pressure is considerably greater, pressure drop problems will increase with increasing humidity as the particles curl and degrade. Results have indicated that when operated in the proper regime, the bulk of the increase in pressure drop results from the conversion of Ba(OH) 2 .8H 2 O to BaCO 3 and not from the hydration of the commercial Ba(OH) 2 .8H 2 O (i.e. Ba(OH) 2 .7.50H 2 O) to Ba(OH) 2 .8H 2 O

  8. Phase controlled synthesis of (Mg, Ca, Ba)-ferrite magnetic nanoparticles with high uniformity

    International Nuclear Information System (INIS)

    Wang, S.F.; Li, Q.; Zu, X.T.; Xiang, X.; Liu, W.; Li, S.

    2016-01-01

    (Mg, Ca, Ba)-ferrite magnetic nanoparticles were successfully synthesized through modifying the atomic ratio of polysaccharide and chelating agent at an optimal sintering temperature. In the process, the polysaccharide plays an important role in drastically shrinking the precursor during the gel drying process. In the metal-complex structure, M"2"+ ion active sites were coordinated by −OH of the water molecules except for EDTA anions. The MFe_2O_4 magnetic nanoparticles exhibited enhanced magnetic properties when compared with nano-MFe_2O_4 of similar particle size synthesized by other synthesis route reported in the literature. In particular, the sintering temperature improves the crystallinity and increases the hysteresis loop squareness ratio of (Mg, Ca, Ba)-ferrite nanoparticles significantly. - Graphical abstract: Schematic representation of the proposed model for MFe_2O_4 nanoparticle synthesis, starting from EDTA-chelated M"2"+ (M=Mg, Ca, or Ba) cations (left). High dispersion (Mg, Ca, Ba)-ferrite magnetic nanoparticles were prepared by a modified polyacrylamide gel route. Optimized utilization of polysaccharide, chelating agent, and sintering temperature allowed the formation of (Mg, Ca, Ba)-ferrite nanoparticles with a narrow diameter distribution. - Highlights: • We report a modified polyacrylamide gel route to synthesize (Mg, Ca, Ba)-ferrite magnetic nanoparticles. • Chelate mechanism of metal ions (Mg, Ca, Ba) and EDTA has been discussed. • Phase transformation process of (Mg, Ca, Ba)-ferrites has been discussed. • The preparation method increases the hysteresis loop squareness ratio of (Mg, Ca, Ba)-ferrite nanoparticles.

  9. Rapid preparation of ultrafine BaSO{sub 3} by SO{sub 2} storage material

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fei; Sha, Feng; Qiao, Xian Shu; Zhao, Tian Xiang; Guo, Bo; Zhang, Jian Bin [College of Chemical Engineering, Inner Mongolia University of Technology, Huhhot (Korea, Republic of)

    2017-01-15

    In this work, a green and efficient process was developed for the preparation of ultrafine BaSO{sub 3} with layered nanostructure surface via the reaction of BaCl{sub 2} with a SO{sub 2} storage material (SO{sub 2}SM) at room temperature. The absorption of SO{sub 2} with equimolar ethylenediamine (EDA) and ethylene glycol (EG) afforded SO{sub 2}SM, which not only offered alkyl sulfite but also released EDA and EG that served as efficient surfactants to promote the formation of BaSO{sub 3} with spherical morphology and porous structure in the process of synthesis of ultrafine BaSO{sub 3}. The factors affecting the morphology and size of BaSO{sub 3} particle were assessed by investigating the effects of SO{sub 2}SM concentration, BaCl{sub 2} concentration, stirring time and speed. It was found that a higher SO{sub 2}SM concentration led to a higher degree of supersaturation, and the particle size of BaSO{sub 3} could be reduced by increasing SO{sub 2}SM concentration. Moreover, under the identified optimal reaction conditions, ultrafine BaSO{sub 3} was obtained with an average diameter of 450 nm. In addition, a plausible formation process of BaSO{sub 3} was proposed to explain the observed reaction results. Overall, the developed process in this work provides an efficient method for the capture, utilization, and conversion of SO{sub 2} into a valuable chemical.

  10. Phase controlled synthesis of (Mg, Ca, Ba)-ferrite magnetic nanoparticles with high uniformity

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S.F., E-mail: wangshifa2006@yeah.net [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan (China); Science and technology on vacuum technology and physics laboratory, Lanzhou Institute of Physics, Lanzhou 730000, Gansu (China); Li, Q. [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan (China); Zu, X.T., E-mail: xtzu@uestc.edu.cn [Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan (China); Xiang, X.; Liu, W. [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan (China); Li, S., E-mail: sean.li@unsw.edu.au [School of Material Science and Engineering, University of New South Wales, Sydney 2052 (Australia)

    2016-12-01

    (Mg, Ca, Ba)-ferrite magnetic nanoparticles were successfully synthesized through modifying the atomic ratio of polysaccharide and chelating agent at an optimal sintering temperature. In the process, the polysaccharide plays an important role in drastically shrinking the precursor during the gel drying process. In the metal-complex structure, M{sup 2+} ion active sites were coordinated by −OH of the water molecules except for EDTA anions. The MFe{sub 2}O{sub 4} magnetic nanoparticles exhibited enhanced magnetic properties when compared with nano-MFe{sub 2}O{sub 4} of similar particle size synthesized by other synthesis route reported in the literature. In particular, the sintering temperature improves the crystallinity and increases the hysteresis loop squareness ratio of (Mg, Ca, Ba)-ferrite nanoparticles significantly. - Graphical abstract: Schematic representation of the proposed model for MFe{sub 2}O{sub 4} nanoparticle synthesis, starting from EDTA-chelated M{sup 2+} (M=Mg, Ca, or Ba) cations (left). High dispersion (Mg, Ca, Ba)-ferrite magnetic nanoparticles were prepared by a modified polyacrylamide gel route. Optimized utilization of polysaccharide, chelating agent, and sintering temperature allowed the formation of (Mg, Ca, Ba)-ferrite nanoparticles with a narrow diameter distribution. - Highlights: • We report a modified polyacrylamide gel route to synthesize (Mg, Ca, Ba)-ferrite magnetic nanoparticles. • Chelate mechanism of metal ions (Mg, Ca, Ba) and EDTA has been discussed. • Phase transformation process of (Mg, Ca, Ba)-ferrites has been discussed. • The preparation method increases the hysteresis loop squareness ratio of (Mg, Ca, Ba)-ferrite nanoparticles.

  11. SKRINING DAN IDENTIFIKASI ISOLAT BAKTERI ENDOFIT UNTUK MENGENDALIKAN PENYAKIT HAWAR DAUN BAKTERI PADA BAWANG MERAH

    Directory of Open Access Journals (Sweden)

    Zurai Resti

    2014-08-01

    Full Text Available Screening and identification of endophytic bacteria to control bacterial leaf blight disease on Shallot. The experiment was conducted in Laboratory and Green House, from January to June 2012.   Laboratory experiment consisted of three steps:  (1 isolation of endophytic bacteria from healthy onion roots, (2In planta /screening of endophytic isolates capable of reducing bacterial leaf blight disease, and (3 molecular identification of potential endophytic isolates.  Treatments of  in planta test were arranged in Completely Randomized Design.  Collected isolates were tested for their capability in controlling bacterial leaf blight disease on shallot.  The variables observed were disease incidence, disease severity, and shallot yield. The results showed that out of 82 isolates successfully isolated, 56 isolates (68.29% were Gram positive, and 26 isolate (31.71% were Gram negative. All isolates were HR negative and pathogenicity negative. Six endophytic isolates showed  better performance in inducing resistance and increasing onion yield. Based on 16S rRNA sequence the six isolates were  Bacillus cereus strain P14 , Bacillus cereus strain Se07, Bacillus sp H1, Bacillus sp SJ1 and Serratia marcescens strain PPM4.

  12. Design, synthesis and luminescence properties of Ba2 YB2 O6 Cl- and Ba2 YB2 O6 F-based phosphors.

    Science.gov (United States)

    Chen, Wanping; Yang, Xin; Liu, Yan; Dai, Xiaoyan

    2015-05-01

    Using a high-temperature solid-state reaction, the chlorine in Ba2 YB2 O6 Cl is gradually replaced by F, and a new compound with the nominal chemical formula Ba2 YB2 O6 F and two phosphors doped with Ce(3+) and Eu(3+) , respectively, are obtained. X-Ray diffraction and photoluminescence spectroscopy are used to characterize the as-synthesized samples. The as-synthesized Ba2 YB2 O6 Cl exhibits bright blue emission in the spectral range ~ 330-410 nm with a maximum around 363 nm under X-ray or UV excitation. Ba2 YB2 O6 F:0.01Ce(3+) exhibits blue emission in the range ~ 340-570 nm with a maximum around 383 nm. Ba2 YB2 O6 F:0.01Eu(3+) exhibits a predominantly (5) D0 -(7)  F2 emission (~610 nm) and the relative intensities of the (5) D0 -(7)  F0,1,2 emissions are tunable under different wavelength UV excitation. The luminescence behaviors of the two phosphors are explained simply in terms of the host composition and site occupancy probability of Ce(3+) and Eu(3+) , respectively. The results indicate that these phosphors have potential application as a blue phosphor or as a red phosphor. Copyright © 2014 John Wiley & Sons, Ltd.

  13. Inter-atomic force constants of BaF{sub 2} by diffuse neutron scattering measurement

    Energy Technology Data Exchange (ETDEWEB)

    Sakuma, Takashi, E-mail: sakuma@mx.ibaraki.ac.jp; Makhsun,; Sakai, Ryutaro [Institute of Applied Beam Science, Ibaraki University, Mito 310-8512 (Japan); Xianglian [College of Physics and Electronics Information, Inner Mongolia University for the Nationalities, Tongliao 028043 (China); Takahashi, Haruyuki [Institute of Applied Beam Science, Ibaraki University, Hitachi 316-8511 (Japan); Basar, Khairul [Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Bandung 40132 (Indonesia); Igawa, Naoki [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai 319-1195 (Japan); Danilkin, Sergey A. [Bragg Institute, Australian Nuclear Science and Technology Organisation, Kirrawee DC NSW 2232 (Australia)

    2015-04-16

    Diffuse neutron scattering measurement on BaF{sub 2} crystals was performed at 10 K and 295 K. Oscillatory form in the diffuse scattering intensity of BaF{sub 2} was observed at 295 K. The correlation effects among thermal displacements of F-F atoms were obtained from the analysis of oscillatory diffuse scattering intensity. The force constants among neighboring atoms in BaF{sub 2} were determined and compared to those in ionic crystals and semiconductors.

  14. Microstructural properties of BaTiO{sub 3} ceramics and thin films

    Energy Technology Data Exchange (ETDEWEB)

    Fundora C, A.; Portelles, J.J.; Siqueiros, J.M. [Posgrado en Fisica de Materiales, Centro de Investigacion Cientifica y de Educacion Superior de Ensenada. Apartado Postal 2861, 22800 Ensenada, Baja California (Mexico)

    2000-07-01

    A microstructural study of BaTiO{sub 3} ceramics obtained by the conventional ceramic method is presented. Targets were produced to grow BaTiO{sub 3} thin films by pulsed laser deposition on Pt/Ti/Si (100) substrates. X-ray diffraction, Auger Electron Spectroscopy, X-ray Photon Spectroscopy and Scanning Electron Microscopy were used to study the properties of the BaTiO{sub 3} ceramic samples and thin films, as deposited and after an annealing process. (Author)

  15. Muon spin depolarization in Gd- and EuBa1Cu3O/sub x/

    International Nuclear Information System (INIS)

    Cooke, D.W.; Hutson, R.L.; Kwok, R.S.

    1988-01-01

    Positive muon spin rotation (μSR) measurements on Gd- and EuBa 2 Cu 3 O/sub x/ (x ∼ 7) have been conducted in the temperature interval 4-300K. For each sample, muons stop both at grain boundaries and within the superconducting grains. Measured magnetic field penetration depths are 1550 and 1900/angstrom/ for two specimens of GdBa 2 Cu 3 O/sub x/, and 1350/angstrom/ for EuBa 2 Cu 3 O/sub x/. 2 refs., 5 figs

  16. Structural, morphological and Raman studies on hybridized PVDF/BaTiO3 nanocomposites

    Science.gov (United States)

    Rajamanickam, N.; Jayakumar, K.; Ramachandran, K.

    2017-05-01

    Hybridized nanocomposites of polyvinylidene fluoride (PVDF) and nano - barium titanate (BaTiO3) were prepared using the solution casting method for different concentrations of nano-BaTiO3 and were characterized by X-ray diffraction and scanning electron microscopy. The flower like structure for morphology was observed in SEM. Raman analysis showed that the modified BaTiO3 particles, due to higher specific surfaces, induce, predominantly, the crystallization of the electrically active β-phase of PVDF, while the initial micron size particles induce the formation of the most common but non-polar α-crystal form.

  17. Phonon modes in Gd1-xCexBa2Cu3O7-δ

    Directory of Open Access Journals (Sweden)

    SH Mozaffari

    2009-08-01

    Full Text Available  XRD and Raman analyses were performed to probe the phase formation and the variation of the normal phonon frequencies of the high temperature superconductor GdBa2Cu3O7-δ upon Ce doping. It was found that in addition to the orthorhombic 123 phase, some nonsuperconducting peaks, which are mainly due to the BaCeO3 secondary phase, are also formed that suppress the superconducting transition temperature. Besides, analysis of the Raman peaks shows that substitutions of Ce for Gd in GdBa2Cu3O7-δ are restricted to low concentrations in favor of impurity island formation .

  18. Thermoluminescence of rare earth doped BaSO/sub 4/ phosphors and its applications

    Energy Technology Data Exchange (ETDEWEB)

    Nagpal, J.S.; Varadharajan, G. (Bhabha Atomic Research Centre, Bombay (India). Div. of Radiological Protection)

    1982-03-01

    Thermoluminescence of synthetic BaSO/sub 4/ samples individually doped with Y, La, Ce, Pr, Nd, Sm, Eu, Tb, Dy and Tm has been studied after ..gamma..- and microwave irradiations. BaSO/sub 4/:Eu has the highest response for ..gamma..-radiation while BaSO/sub 4/:Tb exhibits highest reduction in its ..gamma..-induced TL after exposure to microwave radiation (2425 +- 25 MHz). The reduction depends on the microwave radiant exposure and is independent of the irradiance level in the range 25-200 mW . cm/sup -2/ and hence can be useful for microwave dosimetry.

  19. Metrological activity determination of {sup 133}Ba by sum-peak absolute method

    Energy Technology Data Exchange (ETDEWEB)

    Silva, R.L. da; Delgado, J.U.; Poledna, R.; Santos, A.; Veras, E.V. de; Rangel, J.; Trindade, O.L. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Almeida, M.C.M. de, E-mail: marcandida@yahoo.com.br, E-mail: candida@cnen.gov.br [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    The National Laboratory for Metrology of Ionizing Radiation provides gamma sources of radionuclide and standardized in activity with reduced uncertainties. Relative methods require standards to determine the sample activity while the absolute methods, as sum-peak, not. The activity is obtained directly with good accuracy and low uncertainties. {sup 133}Ba is used in research laboratories and on calibration of detectors for analysis in different work areas. Classical absolute methods do not calibrate {sup 133}Ba due to its complex decay scheme. The sum-peak method using gamma spectrometry with germanium detector standardizes {sup 133}Ba samples. Uncertainties lower than 1% to activity results were obtained.

  20. Melatonin ve Bağışıklık Sistemi

    OpenAIRE

    ÇETİN, E.

    2005-01-01

    Melatonin, pineal bezin beta adrenerjik reseptörlerinin aktivasyonu ile triptofandan sentezlenen bir hormondur.Üretim ve salınımı karanlık ile başlar ve aydınlıkla sona erer. Melatonin, birçok biyolojik fonksiyonun düzenlenmesinderol oynar. Bu derlemede melatonin hakkında genel bilgiler verilerek, melatoninin lenfoid dokular, humoral bağışıklık,hücresel bağışıklık ve kanser üzerine etkileri tartışılmıştır

  1. Polymorphism of tungsten perovskite compounds Ba/sub 2/SEsub(0. 67)WO/sub 6/

    Energy Technology Data Exchange (ETDEWEB)

    Schittenhelm, H J; Kemmler-Sack, S [Tuebingen Univ. (F.R. Germany). Inst. fuer Anorganische Chemie

    1976-09-01

    The compounds Ba/sub 2/SEsub(0.67)WO/sub 6/ with SE = Gd-Lu are polymorphic. Above 1200/sup 0/C the instable cubic modification (ordered perovskite with 4 formula units Ba/sub 2/SEsub(0.67)vacantsub(0.33)WO/sub 6/ per cell) transforms irreversibly into a hexagonal modification with completely filled cationic lattice. For Ba/sub 2/Eusub(0.67)WO/sub 6/ the transformation is incomplete. With SE = Nd and Sm only the cubic modification is formed.

  2. First-principles studies on the adsorption of molecular oxygen on Ba(110) surface

    International Nuclear Information System (INIS)

    Li, S.F.; Xue Xinlian; Li Pinglin; Li Xinjian; Jia Yu

    2006-01-01

    The adsorption of O 2 on Ba(110) surface is studied with first-principles calculations based on density functional theory. Our calculations predict that O 2 may prefer to dissociative adsorption on Ba(110) surface without obvious barrier. Also our results do not support the model of charge transfer from the surface to the molecule as a bond breaking mechanism. Instead, the increasing hybridization between O 2 orbitals and the d states of Ba(110) surface may play an important role in the dissociation adsorption

  3. Adsorption removal of Sr by Barium impregnated 4A Zeolite(BaA) from high radioactive seawater waste

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eil Hee; Lee, Keun Young; Kim, Kwang Wook; Kim, Ik Soo; Chung, Dong Yong; Moon, Jei Kwon; Choi, Jong Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-06-15

    This study investigated the removal of Sr, which was one of the high radioactive nuclides, by adsorption with Barium (Ba) impregnated 4A zeolite (BaA) from high-radioactive seawater waste (HSW). Adsorption of Sr by BaA (BaA-Sr), in the impregnated Ba concentration of above 20.2wt%, was decreased by increasing the impregnated Ba concentration, and the impregnated Ba concentration was suitable at 20.2wt%. The BaA-Sr adsorption was added to the co-precipitation of Sr with BaSO4 precipitation in the adsorption of Sr by 4A (4A-Sr) within BaA. Thus, it was possible to remove Sr more than 99% at m/V (adsorbent weight/solution volume)=5 g/L for BaA and m/V >20 g/L for 4A, respectively, in the Sr concentration of less than 0.2 mg/L (actual concentration level of Sr in HSW). It shows that BaA-Sr adsorption is better than 4A-Sr adsorption in for the removal capacity of Sr per unit gram of adsorbent, and the reduction of the secondary solid waste generation (spent adsorbent etc.). Also, BaA-Sr adsorption was more excellent removal capacity of Sr in the seawater waste than distilled water. Therefore, it seems to be effective for the direct removal of Sr from HSW. On the other hand, the adsorption of Cs by BaA (BaA-Cs) was mainly performed by 4A within BaA. Accordingly, it seems to be little effect of impregnated Ba into BaA. Meanwhile, BaA-Sr adsorption kinetics could be expressed the pseudosecond order rate equation. By increasing the initial Sr concentrations and the ratios of V/m, the adsorption rate constants (k2) were decreased, but the equilibrium adsorption capacities (qe) were increasing. However, with increasing the temperature of solution, k2 was conversely increased, and qe was decreased. The activation energy of BaA-Sr adsorption was 38 kJ/mol. Thus, the chemical adsorption seems to be dominant rather than physical adsorption, although it is not a chemisorption with strong bonding form.

  4. Compounds of the type Ba/sub 3/Bsup(II)M/sub 2/sup(V)O/sub 9/ with Bsup(II) = Mg, Ca, Sr, Ba, and Msup(V) = Nb, Ta

    Energy Technology Data Exchange (ETDEWEB)

    Kemmler-Sack, S; Thumm, I; Herrmann, M [Tuebingen Univ. (Germany, F.R.). Lehrstuhl fuer Anorganische Chemie 2

    1981-08-01

    The hexagonal perovskites Ba/sub 3/Bsup(II)M/sub 2/sup(V)O/sub 9/ (Msup(V) = Nb, Ta) crystallize with Bsup(II) = Mg, Ca in a 3 L structure (sequence (c)/sub 3/) and Bsup(II) = Sr in the hexagonal BaTiO/sub 3/ type (6 L; sequence (hcc)/sub 2/) with an 1:2 order for the B and M ions. Intensity calculations for Ba/sub 3/SrNb/sub 2/O/sub 9/ and Ba/sub 3/SrTa/sub 2/O/sub 9/ gave in the space group P6/sub 3//mmc a refined, intensity related R' value of 8.4% (Nb) and 9.0% (Ta) respectively. For Bsup(II) = Ba the perovskite Ba/sub 3/BaTa/sub 2/O/sub 9/ has an orthorhombic distorted 6 L structure and forms with Ba/sub 3/SrTa/sub 2/O/sub 9/ a continuous series of mixed crystals (Ba/sub 3/Srsub(1-x)Basub(x)Ta/sub 2/O/sub 9/). In the system Ba/sub 3/Srsub(1-x)Basub(x)Nb/sub 2/O/sub 9/ the range of existence of the hexagonal BaTiO/sub 3/ type is confined to the Sr richer end. The pure Ba compound posesses a proper structure type (5 L: Ba/sub 5/BaNb/sub 3/vacantOsub(13.5)vacantsub(1.5)).

  5. Structural phase transition and magnetic properties of double perovskites Ba2CaMO6 (M=W, Re, Os)

    International Nuclear Information System (INIS)

    Yamamura, Kazuhiro; Wakeshima, Makoto; Hinatsu, Yukio

    2006-01-01

    Structures and magnetic properties for double perovskites Ba 2 CaMO 6 (M=W, Re, Os) were investigated. Both Ba 2 CaReO 6 and Ba 2 CaWO 6 show structural phase transitions at low temperatures. For Ba 2 CaReO 6 , the second order transition from cubic Fm3-bar m to tetragonal I4/m has been observed near 120K. For Ba 2 CaWO 6 , the space group of the crystal structure is I4/m at 295K and the transition to monoclinic I2/m has been observed between 220K. Magnetic susceptibility measurements show that Ba 2 CaReO 6 (S=1/2) and Ba 2 CaOsO 6 (S=1) transform to an antiferromagnetic state below 15.4 and 51K, respectively. Anomalies corresponding to their structural phase transition and magnetic transition have been also observed through specific heat measurements

  6. Isothermal cross-sections of Sr-Al-Ge and Ba-Al-Ge systems at 673 K

    International Nuclear Information System (INIS)

    Kutsenok, N.L.; Yanson, T.I.

    1987-01-01

    X-ray and microstructural analyses are used to study phase equilibria in Sr-Al-Ge and Ba-Al-Ge systems. Existence of SrAl 2 Ge 2 , Sr(Al, Ge) 2 Ba(Al, Ge) 2 , Sr 3 Al 2 Ge 2 , Ba 3 Al 2 Ge 2 ternary compounds is confirmed, a new BaGe 4 binary compound and also new ternary compounds of approximate composition Sr 57 Al 30 Ge 13 and Ba 20 Al 40 Ge 40 , which crystal structure is unknown, are detected. Aluminium solubility in SrAl 4 and BaAl 4 binary compounds (0.05 atomic fraction) is determined. Ba(Al, Ge) 2 compound homogeneity region is defined more exactly (aluminium content varies from 0.27 to 0.51 at. fractions)

  7. Barium isotope fractionation during experimental formation of the double carbonate BaMn[CO3](2) at ambient temperature.

    Science.gov (United States)

    Böttcher, Michael E; Geprägs, Patrizia; Neubert, Nadja; von Allmen, Katja; Pretet, Chloé; Samankassou, Elias; Nägler, Thomas F

    2012-09-01

    In this study, we present the first experimental results for stable barium (Ba) isotope ((137)Ba/(134)Ba) fractionation during low-temperature formation of the anhydrous double carbonate BaMn[CO(3)](2). This investigation is part of an ongoing work on Ba fractionation in the natural barium cycle. Precipitation at a temperature of 21±1°C leads to an enrichment of the lighter Ba isotope described by an enrichment factor of-0.11±0.06‰ in the double carbonate than in an aqueous barium-manganese(II) chloride/sodium bicarbonate solution, which is within the range of previous reports for synthetic pure BaCO (3) (witherite) formation.

  8. IR-spectroscopic study and electrical properties of glasses in the Ba(PO3)2-Ba(Hal)2 systems

    International Nuclear Information System (INIS)

    Sokolov, I.A.; Tarlakov, Yu.P.; Murin, I.V.; Pronkin, A.A.

    2000-01-01

    Temperature-concentration dependence of electric conductivity of glasses in the systems Ba(PO 3 ) 2 -Ba(Hal) 2 , where Hal = Cl, Br, I, is studied by the method of conductometry, the numbers of iodide-ions transfer are determined and their concentration dependence is found. Data of IR spectroscopy permitted ascertained participation of halide ions in formation of anionic constituent of the glass structure at the expense of bridge bonds formation, as well as formation of structural-chemical units of [(Hal) - Ba 2+ O - POO 2/2 ] type, their dissociation giving rise to formation of halide ions their dissociation giving rise to formation of halide ions taking part in electric current transfer [ru

  9. Estimation of the specific mass effect in the isotope shifts of energy levels in the optical spectrum of Ba I and Ba II

    International Nuclear Information System (INIS)

    Pendrill, L.R.

    1984-01-01

    A graphical method for separating mass and volume effects from purely optical isotope shift data is presented and compared with King's ''bunching'' method. Recent experimental data on isotope shifts for a wide range of spectral lines in the naturally abundant isotopes of Ba I and Ba II are analysed. Some agreement is found with muonic X-ray data concerning the nuclear size for the isotopes 136, 137 and 138, but there is disagreement (over 20%) for the other isotopes. The level isotope shifts are further parameterised in terms of a linear model, and the specific mass effect is decomposed into sums of one-electron and two-electron shift parameters with respect to the inert-gas like ground state of Ba III. (orig.)

  10. The BaBar Data Reconstruction Control System

    International Nuclear Information System (INIS)

    Ceseracciu, A

    2005-01-01

    The BaBar experiment is characterized by extremely high luminosity and very large volume of data produced and stored, with increasing computing requirements each year. To fulfill these requirements a Control System has been designed and developed for the offline distributed data reconstruction system. The control system described in this paper provides the performance and flexibility needed to manage a large number of small computing farms, and takes full benefit of OO design. The infrastructure is well isolated from the processing layer, it is generic and flexible, based on a light framework providing message passing and cooperative multitasking. The system is distributed in a hierarchical way: the top-level system is organized in farms, farms in services, and services in subservices or code modules. It provides a powerful Finite State Machine framework to describe custom processing models in a simple regular language. This paper describes the design and evolution of this control system, currently in use at SLAC and Padova on ∼450 CPUs organized in 9 farms

  11. Zooplankton community of Parnaíba River, Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Ludmilla Cavalcanti Antunes Lucena

    2015-03-01

    Full Text Available Aim:The objective of the present work is to present a list of species of zooplankton (Rotifera, Cladocera and Copepoda from the Parnaíba River. Additionally, we provide comments on their distribution along the river, and between dry and wet seasons.MethodsZooplankton was collected with a plankton net (60 µm mesh and concentrated into a volume of 80 mL for further analysis, during the dry (October 2010 and wet (April 2011 seasons. Sampling was restricted to the marginal areas at depths between 80 and 150 cm.ResultsA total of 132 species was recorded among the three zooplankton groups studied. During the dry season a total of 82 species was registered and 102 species was registered for the wet season. Rotifera contributed with 66.7% of the species, followed by Cladocera (26.5% and Copepoda (6.8%.ConclusionsThe richness of species observed was high compared to other large rivers in Brazil. In the context of current policies for water management and river diversions in northeastern Brazil, the present study highlights the importance of this river system for biodiversity conservation.

  12. Effect of BaSi2 template growth duration on the generation of defects and performance of p-BaSi2/n-Si heterojunction solar cells

    Science.gov (United States)

    Yachi, Suguru; Takabe, Ryota; Deng, Tianguo; Toko, Kaoru; Suemasu, Takashi

    2018-04-01

    We investigated the effect of BaSi2 template growth duration (t RDE = 0-20 min) on the defect generation and performance of p-BaSi2/n-Si heterojunction solar cells. The p-BaSi2 layer grown by molecular beam epitaxy (MBE) was 15 nm thick with a hole concentration of 2 × 1018 cm-3. The conversion efficiency η increased for films grown at long t RDE, owing to improvements of the open-circuit voltage (V OC) and fill factor (FF), reaching a maximum of η = 8.9% at t RDE = 7.5 min. However, η decreased at longer and shorter t RDE owing to lower V OC and FF. Using deep-level transient spectroscopy, we detected a hole trap level 190 meV above the valence band maximum for the sample grown without the template (t RDE = 0 min). An electron trap level 106 meV below the conduction band minimum was detected for a sample grown with t RDE = 20 min. The trap densities for both films were (1-2) × 1013 cm-3. The former originated from the diffusion of Ba into the n-Si region; the latter originated from defects in the template layer. The crystalline qualities of the template and MBE-grown layers were discussed. The root-mean-square surface roughness of the template reached a minimum of 0.51 nm at t RDE = 7.5 min. The a-axis orientation of p-BaSi2 thin films degraded as t RDE exceeded 10 min. In terms of p-BaSi2 crystalline quality and solar cell performance, the optimum t RDE was determined to be 7.5 min, corresponding to approximately 4 nm in thickness.

  13. BaSi2 formation mechanism in thermally evaporated films and its application to reducing oxygen impurity concentration

    Science.gov (United States)

    Hara, Kosuke O.; Yamamoto, Chiaya; Yamanaka, Junji; Arimoto, Keisuke; Nakagawa, Kiyokazu; Usami, Noritaka

    2018-04-01

    Thermal evaporation is a simple and rapid method to fabricate semiconducting BaSi2 films. In this study, to elucidate the BaSi2 formation mechanism, the microstructure of a BaSi2 epitaxial film fabricated by thermal evaporation has been investigated by transmission electron microscopy. The BaSi2 film is found to consist of three layers with different microstructural characteristics, which is well explained by assuming two stages of film deposition. In the first stage, BaSi2 forms through the diffusion of Ba atoms from the deposited Ba-rich film to the Si substrate while in the second stage, the mutual diffusion of Ba and Si atoms in the film leads to BaSi2 formation. On the basis of the BaSi2 formation mechanism, two issues are addressed. One is the as-yet unclarified reason for epitaxial growth. It is found important to quickly form BaSi2 in the first stage for the epitaxial growth of upper layers. The other issue is the high oxygen concentration in BaSi2 films around the BaSi2-Si interface. Two routes of oxygen incorporation, i.e., oxidation of the Si substrate surface and initially deposited Ba-rich layer by the residual gas, are identified. On the basis of this knowledge, oxygen concentration is decreased by reducing the holding time of the substrate at high temperatures and by premelting of the source. In addition, X-ray diffraction results show that the decrease in oxygen concentration can lead to an increased proportion of a-axis-oriented grains.

  14. Controlled Confinement of Half-metallic 2D Electron Gas in BaTiO3/Ba2FeReO6/BaTiO3 Heterostructures: A First-principles Study

    Science.gov (United States)

    Saha-Dasgupta, Tanusri; Baidya, Santu; Waghmare, Umesh; Paramekanti, Arun

    Using density functional theory calculations, we establish that the half-metallicity of bulk Ba2FeReO6 survives down i to 1 nm thickness in BaTiO3/Ba2FeReO6/BaTiO3 heterostructures grown along the (001) and (111) directions. The confinement of the two-dimensional (2D) electron gas in this quantum well structure arises from the suppressed hybridization between Re/Fe d states and unoccupied Ti d states, and it is further strengthened by polar fields for the (111) direction. This mechanism, distinct from the polar catastrophe, leads to an order of magnitude stronger confinement of the 2D electron gas than that at the LaAlO3/SrTiO3 interface. We further show low-energy bands of (111) heterostructure display nontrivial topological character. Our work opens up the possibility of realizing ultra-thin spintronic devices. Journal Ref: Phys. Rev. B 92, 161106(R) (2015) S.B. and T.S.D thank Department of Science and Technology, India for the support through Thematic Unit of Excellence. AP was supported by NSERC (Canada).

  15. National comparison of activity measurements of 131I, 60Co, and 133Ba in Indonesia

    International Nuclear Information System (INIS)

    Wurdiyanto, Gatot; Marsoem, Pujadi; Widodo, Susilo; Iskandar, Dadong; Muhayatun; Hartoyo, Unggul; Sugino; Gede Sutresna, I.; Hutabarat, Tommy; Suparman, Ibon; Purwanto, Setyo

    2014-01-01

    National comparisons of radioactivity measurements of 131 I and 60 Co (in 2010) and of 133 Ba (in 2011) were carried out within the framework of the National Radiation Metrology Laboratory Program of Indonesia, coordinated by PTKMR-BATAN. Eleven laboratories took part in the comparison, and all measurements were made using gamma spectrometry, on point sources with an activity between 2000 Bq and 6000 Bq. Several laboratories reported values which were more than 10% different from the reference value for 131 I and 133 Ba. Possible reasons for these differences are discussed. This program will be continued with other radionuclides to maintain and control quality assurance for the local laboratories. - Highlights: • PTKMR-BATAN coordinated national comparison of 131 I, 60 Co and 133 Ba. • Eleven laboratories took part in the comparison. • All measurements were done using gamma spectrometry methods. • For 131 I and 133 Ba, 3 laboratories have more than 10% difference from reference laboratory value

  16. Highly selective Ba2+ separations with acyclic, lipophilic di-[N-(X)sulfonyl carbamoyl] polyethers.

    Science.gov (United States)

    Elshani, Sadik; Chun, Sangki; Amiri-Eliasi, Bijan; Bartsch, Richard A

    2005-01-14

    New lipophilic acyclic polyethers with two N-(X)sulfonyl carbamoyl groups of "tunable" acidity exhibit remarkable selectivity for Ba2+ over other alkaline earth metal ions in competitive solvent extraction and transport across polymer inclusion membranes.

  17. Data of evolutionary structure change: 1C7BA-2ZLWD [Confc[Archive

    Lifescience Database Archive (English)

    Full Text Available 1C7BA-2ZLWD 1C7B 2ZLW A D -MLSPADKTNVKAAWGKVGAHAGEYGAEALERMFLSFPT...R VQLSGEEKAAVLALWDKVN--EEEVGGEALGRLLVVYPWTQRFFDSFGDLSNPGAVMGNPKVKAHGKKVLHSFGEGVHHLDNLKGTFAALSEL.../index> 2ZLW D 2ZLWD

  18. Stability of Tl-Ba-Ca-Cu-O superconducting thin films

    International Nuclear Information System (INIS)

    Siegal, M. P.; Overmyer, D. L.; Venturini, E. L.; Padilla, R. R.; Provencio, P. N.

    1999-01-01

    We report the stability of TlBa 2 CaCu 2 O 7 and Tl 2 Ba 2 CaCu 2 O 8 on LaAlO 3 (100) epitaxial thin films, under a variety of conditions. All films are stable in acetone and methanol and with repeated thermal cycling to cryogenic temperatures. Moisture, especially vapor, degrades film quality rapidly. These materials are stable to high temperatures in either N 2 or O 2 ambients. While total degradation, resulting from Tl depletion, occurs at the same temperatures for both phases, 600 degree sign C in N 2 and 700 degree sign C in O 2 , the onset of degradation occurs at somewhat lower temperatures for TlBa 2 CaCu 2 O 7 than for Tl 2 Ba 2 CaCu 2 O 8 . (c) 1999 Materials Research Society

  19. Fabrication of single-grain GdBa 2 Cu 3 O 7− bulk ...

    Indian Academy of Sciences (India)

    Research Articles Volume 74 Issue 5 May 2010 pp 827-832 ... Superconductors; top seeded infiltration and growth process; GdBa2 ... The morphology, microstructure and levitation force of the bulk GdBCO have also been investigated.

  20. Studies on compensating valency substituted BaTi (Mnx/2Nbx/2O3 ...

    Indian Academy of Sciences (India)

    Studies on compensating valency substituted BaTi(1-)Mn/2Nb/2O3 ceramics ... Annealing is observed to improve quality factor `' of the materials with a ... material engineering efforts are required to improve the material properties.

  1. The Battle of the Bakgatla-Ba-Kgafela Community: Access to and ...

    African Journals Online (AJOL)

    MJM Venter

    2017-11-07

    Nov 7, 2017 ... more democratic forms of ownership and governance in general, but ... association; communal land tenure; traditional leadership; Bakgatla-Ba- .... that a dual system prevailed, embodying Western-style national law co-.

  2. Performance simulation of BaBar DIRC bar boxes in TORCH

    Science.gov (United States)

    Föhl, K.; Brook, N.; Castillo García, L.; Cussans, D.; Forty, R.; Frei, C.; Gao, R.; Gys, T.; Harnew, N.; Piedigrossi, D.; Rademacker, J.; Ros García, A.; van Dijk, M.

    2017-12-01

    TORCH is a large-area precision time-of-flight detector based on the DIRC principle. The DIRC bar boxes of the BaBar experiment at SLAC could possibly be reused to form a part of the TORCH detector time-of-flight wall area, proposed to provide positive particle identification of low momentum kaons in the LHCb experiment at CERN. For a potential integration of BaBar bar boxes into TORCH, new imaging readout optics are required. From the several designs of readout optics that have been considered, two are used in this paper to study the effect of BaBar bar optical imperfections on the detector reconstruction performance. The kaon-pion separation powers obtained from analysing simulated photon hit patterns show the performance reduction for a BaBar bar of non-square geometry compared to a perfectly rectangular cross section.

  3. submitter Performance simulation of BaBar DIRC bar boxes in TORCH

    CERN Document Server

    Föhl, K; Castillo García, L; Cussans, D; Forty, R; Frei, C; Gao, R; Gys, T; Harnew, N; Piedigrossi, D; Rademacker, J; Ros García, A; van Dijk, M

    2017-01-01

    TORCH is a large-area precision time-of-flight detector based on the DIRC principle. The DIRC bar boxes of the BaBar experiment at SLAC could possibly be reused to form a part of the TORCH detector time-of-flight wall area, proposed to provide positive particle identification of low momentum kaons in the LHCb experiment at CERN. For a potential integration of BaBar bar boxes into TORCH, new imaging readout optics are required. From the several designs of readout optics that have been considered, two are used in this paper to study the effect of BaBar bar optical imperfections on the detector reconstruction performance. The kaon-pion separation powers obtained from analysing simulated photon hit patterns show the performance reduction for a BaBar bar of non-square geometry compared to a perfectly rectangular cross section.

  4. Laser-induced fluorescence spectra of Ba+*-He exciplexes produced in cold He gas

    International Nuclear Information System (INIS)

    Fukuyama, Yoshimitsu; Matsuo, Yukari; Moriwaki, Yoshiki

    2004-01-01

    We report the observation of laser-induced fluorescence spectra of Ba +* -He exciplexes. The experiment is carried out in an environment of cold gaseous helium at a temperature range of 3-30 K. We have observed the emission spectra of exciplexes by means of excitation of the 6p 2 P 32 2 S 12 transition of Ba + ions. It is found that these spectra are redshifted from the D2 emission line in the free space and are composed of several peaks. The experimental results are reproduced well by theoretical calculation of the emission spectra for vibrational levels of Ba +* -He. We also investigate the vibrational dynamics of the 6p 2 Π 32 state of Ba + *-He, and we have determined the collision-induced vibrational relaxation cross sections of the 6p 2 Π 32 state to be 9.7±1.1 A 2 at 15 K

  5. Development and Characterization of P-doped Ba-122 Superconducting Tapes

    KAUST Repository

    Contarino, D.; Lö hnert, C.; Johrendt, D.; Genovese, Alessandro; Bernini, C.; Malagoli, A.; Putti, M.

    2016-01-01

    Among the recently discovered Fe-based superconducting compounds, the Ba-122 phase has proved to be the more attracting for the development of powder in tube (PIT) processed conductors. In fact, after some years of development, critical current

  6. Structural phase transition of BaZrO3 under high pressure

    International Nuclear Information System (INIS)

    Yang, Xue; Li, Quanjun; Liu, Ran; Liu, Bo; Zhang, Huafang; Jiang, Shuqing; Zou, Bo; Cui, Tian; Liu, Bingbing; Liu, Jing

    2014-01-01

    We studied the phase transition behavior of cubic BaZrO 3 perovskite by in situ high pressure synchrotron X-ray diffraction experiments up to 46.4 GPa at room temperature. The phase transition from cubic phase to tetragonal phase was observed in BaZrO 3 for the first time, which takes place at 17.2 GPa. A bulk modulus 189 (26) GPa for cubic BaZrO 3 is derived from the pressure–volume data. Upon decompression, the high pressure phase transforms into the initial cubic phase. It is suggested that the unstable phonon mode caused by the rotation of oxygen octahedra plays a crucial role in the high pressure phase transition behavior of BaZrO 3

  7. Self-Organized Ni Nanocrystal Embedded in BaTiO3 Epitaxial Film

    Directory of Open Access Journals (Sweden)

    Ge FF

    2010-01-01

    Full Text Available Abstract Ni nanocrystals (NCs were embedded in BaTiO3 epitaxial films using the laser molecular beam epitaxy. The processes involving the self-organization of Ni NCs and the epitaxial growth of BaTiO3 were discussed. With the in situ monitoring of reflection high-energy electron diffraction, the nanocomposite films were engineered controllably by the fine alternation of the self-organization of Ni NCs and the epitaxial growth of BaTiO3. The transmission electron microscopy and the X-ray diffraction characterization confirmed that the composite film consists of the Ni NCs layers alternating with the (001/(100-oriented epitaxial BaTiO3 separation layers.

  8. Electrical properties and structure of glasses in the Ba(PO3)2-MF2 systems, where M = Mg, Ca, Sr, Ba

    International Nuclear Information System (INIS)

    Sokolov, I.A.; Tarlakov, Yu.P.; Murin, I.V.; Pronkin, A.A.

    2000-01-01

    Using the methods of conductometry and IR spectroscopy the concentrational dependences of electric conductivity are studied, the nature of current carriers is determined, the concentrational dependence of transfer numbers is ascertained and structural changes in glasses of the system Ba(PO 3 ) 2 -MF 2 (M = Mg, Ca, Sr, Ba), depending on MF 2 content, are considered. It is shown that F - ions take part in electric current transfer. Influence of crystallochemical nature of alkaline-earth cations on physicochemical properties and structure of the glasses studied is analyzed [ru

  9. Emergence of the sub-THz central peak at phase transitions in artificial BaTiO3/(Ba,Sr)TiO3 superlattices

    International Nuclear Information System (INIS)

    Tikhonov, Yu.A.; Razumnaya, A.G.; Torgashev, V.I.; Zakharchenko, I.N.; Yuzyuk, Yu.I.; El Marssi, M.; Ortega, N.; Kumar, A.; Katiyar, R.S.

    2015-01-01

    A prominent central peak in the sub-THz frequency range was observed in the Raman spectra of BaTiO 3 /(Ba,Sr)TiO 3 (BT/BST) superlattice grown on (001)MgO substrate. Both soft and central mode show an anomaly around 200 K and 280 K, which can be correlated with orthorhombic to monoclinic phase transition of BST and BT, respectively. The observed temperature dependence of the central mode enabled us to explain rather broad temperature dependence of the dielectric permittivity previously observed in BT/BST superlattices. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. The new barium mercuride BaHg6 and ternary indium and gallium derivatives

    International Nuclear Information System (INIS)

    Wendorff, Marco; Röhr, Caroline

    2013-01-01

    Highlights: ► The new binary Hg-rich mercuride BaHg 6 crystallizes with a singular structure type. ► Ternary In substituted compounds are isotypic, whereas Ga substituted compounds are only structurally related. ► Structure relation to other Hg-rich alkali and alkaline earth mercurides. ► Discussion of covalent and metallic bonding aspects, as found by structure features and band structure calculations. - Abstract: The new binary barium mercuride BaHg 6 and the derived ternary indium and gallium containing compounds BaIn 1.2 Hg 4.8 and BaGa 0.8 Hg 5.2 were synthesized from melts of the elements, which were slowly cooled from 500 to 200 °C. Their crystal structures have been determined by means of single crystal X-ray diffraction. The binary mercuride BaHg 6 (Pnma, a = 1338.9(3), b = 519.39(13), c = 1042.6(4) pm, Z = 4, R1 = 0.0885) and the isotypic indium substituted compound BaIn 1.2 Hg 4.8 as well as the structurally related gallium mercuride BaGa 0.8 Hg 5.2 (Cmcm, a = 729.77(7), b = 1910.1(2), c = 507.48(5) pm, Z = 4, R1 = 0.0606) crystallize with new structure types. Common features of both structures are planar nets of five- and eight-membered Hg rings, stacked perpendicular to the shortest axes. According to their lengths, the Hg–Hg bonds can be classified into three groups: strong, short ones (I, 285–292 pm), which are only found inside the nets, and longer distances (II), still carrying bond critical points, around 300 pm. Further contacts (III) serve to complete the coordination spheres of Hg/M (320–358 pm). The overall coordination numbers of Hg/M range from 10 to 13. The Ba cations are positioned in the centers of the octagons of the Hg/M nets, thus exhibiting a 5:8:5, i.e. 18, coordination by Hg/M atoms. DFT calculations of the electronic band structure of pure BaHg 6 and ordered models of the indium ( ′ BaInHg 5 ′ ) and the gallium ( ′ BaGaHg 5 ′ ) mercurides were performed using the FP-LAPW method. The calculated Bader charges

  11. Phase equilibrium in Al-Li-Ca(Sr, Ba) systems at 423 K

    International Nuclear Information System (INIS)

    Ganieva, N.I.; Nazarov, Kh.M.; Ganiev, I.N.

    1999-01-01

    The isothermic cross section of the Al-Li-Ca(Sr, Ba) systems at 423 K is obtained. It is shown that the Al-Li-Sr ternary system as well as the Li-Sr binary system differ by nature of components in interaction from the Al-Li-Ca(Ba) systems. This is obvious by formation of the SrAl 2 Li 2 ternary intermetallide, which is not observed in the systems with participation of barium and calcium [ru

  12. The synthesis and characterization of p(nBA-DEAEMA) polymer

    Science.gov (United States)

    Jiang, X. M.; Zhu, J.; Duan, Y. Y.

    2018-01-01

    In this paper, the polymer of p (nBA-DEAEMA) was polymerized and characterized. The structure of copolymer was characterized by FT-IR and 1HNMR, and the analysis of particle size, appearance and rheology was determined too. The results showed that, the p (nBA-DEAEMA) was synthesised successful, and it could become a surface modification for the inner face of artificial trachea, after further optimization.

  13. Anomalous properties of PrBa2Cu3O7: a comment

    International Nuclear Information System (INIS)

    Sampathkumaran, E.V.

    1992-01-01

    Considerable attention has been paid in the literature to understand the suppression of superconductivity and the large Neel temperature of the Pr sub-lattice in PrBa 2 Cu 3 O 7 . Here we briefly recall the superconducting and magnetic anomalies noted earlier in other Pr based systems due to the partial delocalisation of the Pr-4f orbital to show that the gross anomalous features observed for PrBa 2 Cu 4 O 7 are not unique. (orig.)

  14. Pulsed Field Waveforms for Magnetization of HTS Gd-Ba-Cu-O Bulk Magnets

    International Nuclear Information System (INIS)

    Ida, T; Matsuzaki, H; Morita, E; Sakashita, H; Harada, T; Ogata, H; Kimura, Y; Miki, M; Kitano, M; Izumi, M

    2006-01-01

    Progress in pulse magnetization technique for high-temperature superconductor bulks of melt-textured RE-Ba-Cu-O with large diameter is important for the realization of power applications. We studied the pulsed power source and pulsed field waveforms to enhance to improve the magnetization properties for Gd-Ba-Cu-O bulk. The risetime and duration of pulse waveform effectively varied distribution of magnetic flux

  15. Structural Distortion Stabilizing the Antiferromagnetic and Semiconducting Ground State of BaMn2As2

    Directory of Open Access Journals (Sweden)

    Ekkehard Krüger

    2016-09-01

    Full Text Available We report evidence that the experimentally found antiferromagnetic structure as well as the semiconducting ground state of BaMn 2 As 2 are caused by optimally-localized Wannier states of special symmetry existing at the Fermi level of BaMn 2 As 2 . In addition, we find that a (small tetragonal distortion of the crystal is required to stabilize the antiferromagnetic semiconducting state. To our knowledge, this distortion has not yet been established experimentally.

  16. Magnetothermopower in A2−xLaxFeMoO6 (A = Sr, Ba

    Directory of Open Access Journals (Sweden)

    G. V. M. Williams

    2017-01-01

    Full Text Available A magnetothermopower has been observed in electronically spin-polarized polycrystalline Sr2-xLaxFeMoO6 and Ba2FeMoO6. The magnetothermopower is linear up to ~50 K for Sr2-xLaxFeMoO6 and linear up to ~270 K for Ba2FeMoO6. We suggest that the magnetothermopower may arise from a spin-tunneling magnetothermopower between the grains.

  17. Commensurability oscillations in NdBa2Cu3Oy single crystals

    Indian Academy of Sciences (India)

    gated by angular dependent magnetization in very pure twinned and twin-free NdBa2 Cu3 Oy single ... The layered structure and the c-axis coherence length, ξc ≈ 4 ˚A, smaller than the lattice ... The high quality of both crystals is demonstrated by ... Commensurability oscillations in NdBa2Cu3Oy single crystals. 2. 3. 4. 5. 6.

  18. Crystal structure of barium hydride, determined by neutron diffraction experiments on BaD2

    International Nuclear Information System (INIS)

    Bronger, W.; Scha Chi-Chien; Mueller, P.

    1987-01-01

    A reinvestigation of the structure of BaH 2 and BaD 2 was performed on powdered samples by X-ray- and neutron diffraction experiments. It is shown, that the hydrogen positions correspond with those found in calcium deuteride and not with those proposed in the literature. The classification of barium hydride in the PbCl 2 structure type is discussed. (author)

  19. Using barium alkoxide for sol-gel-preparation of BaTiO sub 3

    Energy Technology Data Exchange (ETDEWEB)

    Limmer, G.; Buerke, H.; Kohl, R.; Tomandl, G. (Erlangen-Nuernberg Univ., Erlangen (Germany, F.R.). Inst. fuer Werkstoffwissenschaften)

    1989-01-01

    For producing multilayer ceramics there exists a demand for low firing temperatures. This would allow the use of cheaper electrode materials. Pure BaTiO{sub 3} usually sinters in the range of 1350deg C to 1400deg C and shows a coarse-grained microstructure. Therefore the use of sintering aids, like Pb, Bi-compounds, is necessary. Our aim is to synthesize highly sinteractive BaTiO{sub 3} powders to avoid the usage of sintering aids. (orig.).

  20. BaCO3 mediated modifications in structural and magnetic properties of natural nanoferrites

    Science.gov (United States)

    Widanarto, W.; Jandra, M.; Ghoshal, S. K.; Effendi, M.; Cahyanto, W. T.

    2015-04-01

    Preparing M-type barium hexaferrite and improving the magnetic response of natural ferrites by incorporating barium carbonate (BaCO3) is ever-demanding. Series of barium carbonate doped ferrites with composition (100-x)Fe3O4·xBaCO3 (x=0, 10, 20, 30 wt%) are prepared through solid state reaction method and sintered gradually at temperatures of 800 and 1000 °C. Nanoparticles of natural ferrite and commercial BaCO3 are used as raw materials. Impacts of BaCO3 on structural and magnetic properties of these synthesized ferrites are inspected. The obtained ferrites are characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) at room temperature. Uniform barium hexaferrite particles in terms of both morphology and size are not achieved. The average crystallite size of BaFe12O19 is observed to be within 30-600 nm. The sintering process results phase transformation from Fe3O4 (magnetite) to α-Fe2O3 (hematite) and the formation of hexagonal barium ferrite crystals. The occurrence of barium crystal is found to enhance with the increase of BaCO3 concentrations up to 20 wt% and suddenly drop at 30 wt%. Saturation and remanent magnetization of the doped ferrites are significantly augmented up to 16.37 and 8.92 emu g-1, respectively compared to their pure counterpart. Furthermore, the coercivity field is slightly decreased as BaCO3 concentrations are increased. BaCO3 mediated improvements in the magnetic response of natural ferrites are demonstrated.

  1. BaYb2F8, a new radiation hard Cherenkov radiator for electromagnetic calorimeters

    International Nuclear Information System (INIS)

    Aseev, A.A.; Devitsin, E.G.; Komar, A.A.; Kozlov, V.A.; Hovsepyan, Yu.I.; Potashov, S.Yu.; Sokolovsky, K.A.; Uvarova, T.V.; Vasilchenko, V.G.

    1992-01-01

    Radiation hardness and optical properties of a new Cherenkov radiator, heavy fluoride BaYb 2 F 8 doped with various elements, have been studied. The above mentioned crystal has the density of 7 g/cm 3 , the radiation length is 1.28 cm and the Moliere radius 2.44 cm. High radiation hardness has been demonstrated for BaYb 2 F 8 doped with Tm, Pr, Tb. (orig.)

  2. Consideration of the band-gap tunability of BaSi2 by alloying with Ca or Sr based on the electronic structure calculations

    International Nuclear Information System (INIS)

    Imai, Yoji; Watanabe, Akio

    2007-01-01

    The electronic structures and total energies of BaSi 2 -SrSi 2 and BaSi 2 -CaSi 2 systems have been calculated using the first-principle pseudopotential method to clarify the band gap tunability of BaSi 2 by alloying with Sr or Ca. From an energetic consideration of the compounds where all the Ba I sites or all the Ba II sites of the BaSi 2 lattice are preferentially replaced by Sr or Ca, it is expected that the Ba I site will be preferentially replaced by Sr rather than the Ba II sites. Compounds where all the Ba II sites are replaced by Sr or all the Ba II or all the Ba I sites are replaced by Ca are energetically unfavorable compared to the undissolved system of BaSi 2 and SrSi 2 or CaSi 2 . The effect of the addition of Sr or Ca into the BaSi 2 lattice on the gap value is different depending on the replaced sites of Ba. The replacement of Ba I site by Sr will broaden the band gap of BaSi 2 , which is consistent with the observed results

  3. (Ba+Sr)/Ti ratio dependence of the dielectric properties for (Ba0.5Sr0.5)TiO3 thin films prepared by ion beam sputtering

    Science.gov (United States)

    Yamamichi, Shintaro; Yabuta, Hisato; Sakuma, Toshiyuki; Miyasaka, Yoichi

    1994-03-01

    (Ba0.5Sr0.5)TiO3 thin films were prepared by ion beam sputtering from powder targets with (Ba+Sr)/Ti ratios ranging from 0.80 to 1.50. All of the perovskite (Ba,Sr)TiO3 films were single phase except for the film with a (Ba+Sr)/Ti ratio of 1.41. The dielectric constant values notably depended on the (Ba+Sr)/Ti ratio for films thicker than 70 nm. The highest dielectric constant of 580 was achieved for the 5% (Ba+Sr) rich film. This (Ba+Sr)/Ti ratio dependence was diminished by the thickness dependence for thinner films. The grain sizes for the 9% (Ba+Sr) rich film and for the 6% (Ba+Sr) poor film ranged from 70 to 100 nm and from 30 to 60 nm, respectively. This grain size difference could explain why slightly A-site rich (Ba,Sr)TiO3 films have a larger dielectric constant than A-site poor films.

  4. Positron annihilation lifetime study of positive temperature coefficient BaTiO3 samples

    International Nuclear Information System (INIS)

    Ling Chen; Mingkang Teng; Guanghou Wang; Xiaoyun Li; Tianchang Lu

    1989-01-01

    In order to investigate the doped vacancies in BaTiO 3 samples as well as their influence on the positive temperature coefficient (PTC) the positron annihilation lifetime spectroscopy was applied. Two groups of BaTiO 3 samples with BaO excess were prepared by doping different concentrations of La 2 O 3 and Nb 2 O 5 , respectively in the range from 0.1 to 3 at%. A third group of samples of two Sb-doped PTC BaTiO 3 semiconductors with excess BaO or TiO 2 were studied by the aid of positron technique before and after being reduced. It is shown that the positron lifetime parameters are sensitive to changes in the vacancy concentration in BaTiO 3 ceramics near the 0.1 mol% region. But they are almost unchanged during reduction processing; the resistivity of samples changed by one to two orders of magnitude through the reduction. It can be concluded that the PTC effect is due to oxygen on the grain boundary rather than vacancies, and that the Heywang-Jonker model is more reasonable

  5. Thermoelectric properties of Cu/Ag doped type-III Ba24Ge100 clathrates

    Science.gov (United States)

    Fu, Jiefei; Su, Xianli; Yan, Yonggao; Liu, Wei; Zhang, Zhengkai; She, Xiaoyu; Uher, Ctirad; Tang, Xinfeng

    2017-09-01

    Type-III Ba24Ge100 clathrates possess low thermal conductivity and high electrical conductivity at room temperature and, as such, have a great potential as thermoelectric materials for power generation. However, the Seebeck coefficient is very low due to the intrinsically high carrier concentration. In this paper, a series of Ba24CuxGe100-x and Ba24AgyGe100-y specimens were prepared by vacuum melting combined with the subsequent spark plasma sintering (SPS) process. Doping Cu or Ag on the Ge site not only suppresses the concentration of electrons but it also decreases the thermal conductivity. In addition, the carrier mobility and the Seebeck coefficient increase due to the decrease in the carrier concentration. Thus, the power factor is greatly improved, leading to an improvement in the dimensionless figure of merit ZT. Cu-doped Ba24Cu6Ge94 reaches the maximum ZT value of about 0.17 at 873 K, while Ag-doped Ba24Ag6Ge94 attains the dimensionless figure of merit ZT of 0.31 at 873 K, more than 2 times higher value compared to un-doped Ba24Ge100.

  6. Non-observation of 12C cluster decay of 114Ba

    International Nuclear Information System (INIS)

    Guglielmetti, A.; Bonetti, R.; Poli, G.; Collatz, R.; Hu, Z.; Kirchner, R.; Roeckl, E.; Gunn, N.; Price, P.B.; Weaver, B.A.; Westphal, A.; California Univ., Berkeley, CA; Szerypo, J.

    1997-10-01

    By means of the on-line mass separator at Gesellschaft fuer Schwerionenforschung, Darmstadt, we produced 114 Ba through the 58 Ni( 58 Ni,2n) reaction, separated it as a 114 Ba 19 F + beam, and implanted it into a stopper foil positioned in the center of an array of track detectors, which were used to search for 12 C radioactivity of 114 Ba. A total number of (5.4±1.7).10 4 114 Ba atoms were implanted. No 12 C event was found after a total exposure time of 116 hours, corresponding to a 58 Ni beam dose of 1.3.10 17 . The resulting upper limit of 3.4.10 -5 (84% c. 1.) for the branching ratio for 12 C decay of 114 Ba is considerably lower than the limits obtained in previous experiments, which represents an inconsistency at levels of more than 90%. A semiempirical estimate of 19.3 MeV for the upper limit of the Q-value for 12 C decay of 114 Ba is derived. (orig.)

  7. Photoluminescence properties of BaMoO4 amorphous thin films

    International Nuclear Information System (INIS)

    Marques, Ana Paula Azevedo; Melo, Dulce M.A. de; Longo, Elson; Paskocimas, Carlos A.; Pizani, Paulo S.; Leite, Edson R.

    2005-01-01

    BaMoO 4 amorphous and crystalline thin films were prepared from polymeric precursors. The BaMoO 4 was deposited onto Si wafers by means of the spinning technique. The structure and optical properties of the resulting films were characterized by FTIR reflectance spectra, X-ray diffraction (XRD), atomic force microscopy (AFM) and optical reflectance. The bond Mo-O present in BaMoO 4 was confirmed by FTIR reflectance spectra. XRD characterization showed that thin films heat-treated at 600 and 200 deg. C presented the scheelite-type crystalline phase and amorphous, respectively. AFM analyses showed a considerable variation in surface morphology by comparing samples heat-treated at 200 and 600 deg. C. The reflectivity spectra showed two bands, positioned at 3.38 and 4.37 eV that were attributed to the excitonic state of Ba 2+ and electronic transitions within MoO 2- 4 , respectively. The optical band gaps of BaMoO 4 were 3.38 and 2.19 eV, for crystalline (600 deg. C/2 h) and amorphous (200 deg. C/8 h) films, respectively. The room-temperature luminescence spectra revealed an intense single-emission band in the visible region. The PL intensity of these materials was increased upon heat-treatment. The excellent optical properties observed for BaMoO 4 amorphous thin films suggested that this material is a highly promising candidate for photoluminescent applications

  8. Superconductivity in the U(Th)-Y-Ba-Cu-O systems

    International Nuclear Information System (INIS)

    Qin Qizong; He Adi; Jia Weijie; Ma Lidun; Cheng Huansheng; Hua Zhongyi

    1989-01-01

    High T c superconductivity has been observed both resistively and magnetically in the new U(Th)-Y-Ba-Cu-O systems. The zero resistance temperature of the three samples with nominal composition of U 0.1 Y 1.1 Ba 0.8 Cu O 4-z , U 0.15 Y 1.05 Ba 0.8 Cu 4-z and Th 0.3 Y 0.8 Ba 0.8 Cu 4-z is 87K, 79K and 74K, respectively. The result of ac magnetic susceptibility measurement implies that the superconducting state is realized in the U-doped samples below 90K. The stoichimetry of the U-Y-Ba-Cu O superconductors has the aid of Rutherford backscattering and nuclear reaction 16 O(d, p) 17 O. The analytical results show that the 'real composition' of somples may be different from that of the nomial composition. The X ray diffraction analysis of the U-Y-Ba-Cu-O system shows that none of the peaks can be fitted to the uranium oxides and the other raw materiale structure, and its pattern may be attributed to new multiple phases with structure different from the known singlephase superconducting oxides

  9. Fabrication of Ba-K-Bi-O thick film artefacts with improved critical currents

    International Nuclear Information System (INIS)

    Moore, J.C.; Salter, C.J.; Jenkins, R.J.; Grovenor, C.R.M.; Jones, H.

    1993-01-01

    The Ba-K-Bi-O system has a maximum T c of around 30K for a composition of Ba 0.6 K 0.4 BiO 3 . Fabrication of good quality single phase samples is extremely difficult and requires careful control of the fabrication conditions. Successful synthesis procedures for Ba-K-Bi-O powder and melt cast material which allow some control of the potassium content of the product were established by Hinks et al. The process is based on a melt and sinter step in an inert atmosphere which creates oxygen vacancies and allows potassium to enter the lattice. The oxygen vacancies are then filled by a subsequent oxygen anneal to obtain superconductivity. Ba-K-Bi-O is, therefore, metastable and consequently difficult to synthesise. There have been few reports of transport measurements and even fewer reports of transport critical currents for bulk material. It is often accepted that Ba-K-Bi-O has an intrinsically low critical current, and extremely poor critical current densities of 0.05 Acm -2 have been quoted for melt cast material. It has been suggested that the presence of weak links is the cause. However, there has been little research into the relationship between process conditions and superconducting properties for melt processed Ba-K-Bi-O to confirm this. (orig.)

  10. Two steps hydrothermal growth and characterisations of BaTiO3 films composed of nanowires

    Science.gov (United States)

    Zawawi, Che Zaheerah Najeehah Che Mohd; Salleh, Shahril; Oon Jew, Lee; Tufail Chaudhary, Kashif; Helmi, Mohamad; Safwan Aziz, Muhammad; Haider, Zuhaib; Ali, Jalil

    2018-05-01

    Barium titanate (BaTiO3) films composed of nanowires have gained considerable research interest due to their lead-free composition and strong energy conversion efficiency. BaTiO3 films can be developed with a simple two steps hydrothermal reactions, which are low cost effective. In this research, BaTiO3 films were fabricated on titanium foil through two steps hydrothermal method namely, the growth of TiO2 and followed by BaTiO3 films. The structural evolutions and the dielectric properties of the films were investigated as well. The structural evolutions of titanium dioxide (TiO2) and BaTiO3 nanowires were characterized using X-ray diffraction and scanning electron microscopy. First step of hydrothermal reaction, TiO2 nanowires were prepared in varied temperatures of 160 °C, 200 °C and 250 °C respectively. Second step of hydrothermal reaction was performed to produce a layer of BaTiO3 films.

  11. Sediment pollution in margins of the Lake Guaíba, Southern Brazil.

    Science.gov (United States)

    de Andrade, Leonardo Capeleto; Tiecher, Tales; de Oliveira, Jessica Souza; Andreazza, Robson; Inda, Alberto Vasconcellos; de Oliveira Camargo, Flávio Anastácio

    2017-12-02

    Sediments are formed by deposition of organic and inorganic particles on depth of water bodies, being an important role in aquatic ecosystems, including destination and potential source of essential nutrients and heavy metals, which may be toxic for living organisms. The Lake Guaíba supplies water for approximately two million people and it is located in the metropolitan region of Porto Alegre, Rio Grande do Sul State, Brazil. Thus, the aim of this study was to evaluate the sediment pollution in the margins of Lake Guaíba in the vicinity of Porto Alegre city. Surface sediment was sampled in 12 sites to assess the concentration of several elements (C, N, P, Fe, Al, Ca, Mg, Na, K, Mn, Ba, Zn, V, Pb, Cu, Cr, Ni, Cd, Mo, and Se) and the mineralogical composition. Sediment in margins of Lake Guaíba presented predominantly (> 95%) sandy fraction in all samples, but with significant differences between evaluated sites. Sediments in the margins of Lake Guaíba showed indications of punctual water pollution with Pb, Cu, Cr, Ni, TOC, TKN, and P, mainly derived from urban streams that flow into the lake. In order to solve these environmental liabilities, public actions should not focus only on Guaíba, but also in the streams that flow into the lake.

  12. Evolution of deformation in neutron-rich Ba isotopes up to A =150

    Science.gov (United States)

    Licǎ, R.; Benzoni, G.; Rodríguez, T. R.; Borge, M. J. G.; Fraile, L. M.; Mach, H.; Morales, A. I.; Madurga, M.; Sotty, C. O.; Vedia, V.; De Witte, H.; Benito, J.; Bernard, R. N.; Berry, T.; Bracco, A.; Camera, F.; Ceruti, S.; Charviakova, V.; Cieplicka-Oryńczak, N.; Costache, C.; Crespi, F. C. L.; Creswell, J.; Fernandez-Martínez, G.; Fynbo, H.; Greenlees, P. T.; Homm, I.; Huyse, M.; Jolie, J.; Karayonchev, V.; Köster, U.; Konki, J.; Kröll, T.; Kurcewicz, J.; Kurtukian-Nieto, T.; Lazarus, I.; Lund, M. V.; Mǎrginean, N.; Mǎrginean, R.; Mihai, C.; Mihai, R. E.; Negret, A.; Orduz, A.; Patyk, Z.; Pascu, S.; Pucknell, V.; Rahkila, P.; Rapisarda, E.; Regis, J. M.; Robledo, L. M.; Rotaru, F.; Saed-Samii, N.; Sánchez-Tembleque, V.; Stanoiu, M.; Tengblad, O.; Thuerauf, M.; Turturica, A.; Van Duppen, P.; Warr, N.; IDS Collaboration

    2018-02-01

    The occurrence of octupolar shapes in the Ba isotopic chain was recently established experimentally up to N =90 . To further extend the systematics, the evolution of shapes in the most neutron-rich members of the Z =56 isotopic chain accessible at present, Ba,150148, has been studied via β decay at the ISOLDE Decay Station. This paper reports on the first measurement of the positive- and negative-parity low-spin excited states of 150Ba and presents an extension of the β -decay scheme of 148Cs. Employing the fast timing technique, half-lives for the 21+ level in both nuclei have been determined, resulting in T1 /2=1.51 (1 ) ns for 148Ba and T1 /2=3.4 (2 ) ns for 150Ba. The systematics of low-spin states, together with the experimental determination of the B (E 2 :2+→0+) transition probabilities, indicate an increasing collectivity in Ba-150148, towards prolate deformed shapes. The experimental data are compared to symmetry conserving configuration mixing (SCCM) calculations, confirming an evolution of increasingly quadrupole deformed shapes with a definite octupolar character.

  13. Hydrothermal growth of highly textured BaTiO3 films composed of nanowires

    International Nuclear Information System (INIS)

    Zhou Zhi; Tang Haixiong; Sodano, Henry A; Lin Yirong

    2013-01-01

    Textured barium titanate (BaTiO 3 ) films are attracting immense research interest due to their lead-free composition and excellent piezoelectric and dielectric properties. Most synthesis methods for these films require a high temperature, leading to the formation of a secondary phase and an overall decrease in the electrical properties of the ceramic. In order to alleviate these issues, a novel fabrication method is introduced by transferring oriented rutile TiO 2 nanowires to a textured BaTiO 3 film at temperatures below 160 °C. The microstructure and thickness of the fabricated BaTiO 3 films were characterized by scanning electron microscopy, and the crystal structure and degree of orientation were evaluated by x-ray diffraction patterns using the Lotgering method. It is shown that the thickness of the BaTiO 3 film can be controlled by the length of TiO 2 nanowire array template, and the degree of orientation of the textured BaTiO 3 films is highly dependent on the film thickness; the crystallographic orientation has been measured to reach up to 87%. The relative dielectric constant (ε r = 1300) and ferroelectric properties (P r = 2.7 μC cm −2 , E c = 4.0 kV mm −1 ) of the textured BaTiO 3 films were also characterized to demonstrate their potential application in sensors, random access memory, and micro-electromechanical systems. (paper)

  14. Mapping the involvement of BA 4a and 4p during Motor Imagery.

    Science.gov (United States)

    Sharma, Nikhil; Jones, P S; Carpenter, T A; Baron, Jean-Claude

    2008-05-15

    Motor Imagery (MI) is an attractive but intriguing means to access the motor network. There are marked inconsistencies in the functional imaging literature regarding the degree, extent and distribution of the primary motor cortex (BA 4) involvement during MI as compared to Executed Movement (EM), which may in part be related to the diverse role of BA 4 and its two subdivisions (i.e., 4a and 4p) in motor processes as well as to methodological issues. Here we used fMRI with monitoring of compliance to show that in healthy volunteers optimally screened for their ability to perform MI the contralateral BA 4 is involved during MI of a finger opposition sequence (2, 3, 4, 5; paced at 1 Hz), albeit less than during EM of the same sequence, and in a location sparing the hand area. Furthermore, both 4a and 4p subdivisions were found to be involved in MI, but the relative involvement of BA 4p appeared more robust and closer to that seen with EM. We suggest that during MI the role of BA 4 and its subdivisions may be non-executive, perhaps related to spatial encoding, though clearly further studies are needed. Finally, we report a similar hemispheric activation balance within BA 4 with both tasks, which extends the commonalities between EM and MI.

  15. Photoluminescent BaMoO4 nanopowders prepared by complex polymerization method (CPM)

    International Nuclear Information System (INIS)

    Azevedo Marques, Ana Paula de; Melo, Dulce M.A. de; Paskocimas, Carlos A.; Pizani, Paulo S.; Joya, Miryam R.; Leite, Edson R.; Longo, Elson

    2006-01-01

    The BaMoO 4 nanopowders were prepared by the Complex Polymerization Method (CPM). The structure properties of the BaMoO 4 powders were characterized by FTIR transmittance spectra, X-ray diffraction (XRD), Raman spectra, photoluminescence spectra (PL) and high-resolution scanning electron microscopy (HR-SEM). The XRD, FTIR and Raman data showed that BaMoO 4 at 300 deg. C was disordered. At 400 deg. C and higher temperature, BaMoO 4 crystalline scheelite-type phases could be identified, without the presence of additional phases, according to the XRD, FTIR and Raman data. The calculated average crystallite sizes, calculated by XRD, around 40 nm, showed the tendency to increase with the temperature. The crystallite sizes, obtained by HR-SEM, were around of 40-50 nm. The sample that presented the highest intensity of the red emission band was the one heat treated at 400 deg. C for 2 h, and the sample that displayed the highest intensity of the green emission band was the one heat treated at 700 deg. C for 2 h. The CPM was shown to be a low cost route for the production of BaMoO 4 nanopowders, with the advantages of lower temperature, smaller time and reduced cost. The optical properties observed for BaMoO 4 nanopowders suggested that this material is a highly promising candidate for photoluminescent applications

  16. Bioaccessibility of Ba, Cu, Pb, and Zn in urban garden and orchard soils

    International Nuclear Information System (INIS)

    Cai, Meifang; McBride, Murray B.; Li, Kaiming

    2016-01-01

    Exposure of young children to toxic metals in urban environments is largely due to soil and dust ingestion. Soil particle size distribution and concentrations of toxic metals in different particle sizes are important risk factors in addition to bioaccessibility of these metals in the particles. Analysis of particle size distribution and metals concentrations for 13 soils, 12 sampled from urban gardens and 1 from orchard found that fine particles (<105 μm) comprised from 22 to 66% by weight of the tested soils, with Ba, Cu, Pb and Zn generally at higher concentrations in the finer particles. However, metal bioaccessibility was generally lower in finer particles, a trend most pronounced for Ba and Pb. Gastric was higher than gastrointestinal bioaccessibility for all metals except Cu. The lower bioaccessibility of Pb in urban garden soils compared to orchard soil is attributable to the higher organic matter content of the garden soils. - Highlights: • The bioaccessibility of metals in urban garden and orchard soils was measured. • Ba, Cu, Pb, Zn were concentrated in fine particles of the soils. • Bioaccessibilities of Ba and Pb were generally lower in fine particles of soils. • Pb bioaccessibility was generally lower in soils with higher organic matter content. • Pb bioaccessibility was lower in urban garden soils than in an orchard soil. - Pb and other trace metals (Ba, Cu, Zn) were concentrated in fine particles of urban and orchard soils, but the bioaccessibility of Ba and Pb was generally lower in finer particles.

  17. Phase equilibria, crystal chemistry, electronic structure and physical properties of Ag-Ba-Ge clathrates

    Energy Technology Data Exchange (ETDEWEB)

    Zeiringer, I.; Chen Mingxing [Institute of Physical Chemistry, University of Vienna, Waehringerstr. 42, 1090 Wien (Austria); Bednar, I.; Royanian, E.; Bauer, E. [Institute of Solid State Physics, Vienna University of Technology, Wiedner Hauptstr. 8-10, 1040 Wien (Austria); Podloucky, R.; Grytsiv, A. [Institute of Physical Chemistry, University of Vienna, Waehringerstr. 42, 1090 Wien (Austria); Rogl, P., E-mail: peter.franz.rogl@univie.ac.at [Institute of Physical Chemistry, University of Vienna, Waehringerstr. 42, 1090 Wien (Austria); Effenberger, H. [Institute of Mineralogy and Crystallography, University of Vienna, A-1090 Wien (Austria)

    2011-04-15

    In the Ag-Ba-Ge system the clathrate type-{Iota} solid solution, Ba{sub 8}Ag{sub x}Ge{sub 46-x-y{open_square}y}, extends at 800 deg. C from binary Ba{sub 8}Ge{sub 43{open_square}3} ({open_square} is a vacancy) to Ba{sub 8}Ag{sub 5.3}Ge{sub 40.7}. For the clathrate phase (1 {<=} x {<=} 5.3) the cubic space group Pm3-bar n was established by X-ray powder diffraction and confirmed by X-ray single-crystal analyses of the samples Ba{sub 8}Ag{sub 2.3}Ge{sub 41.9{open_square}1.8} and Ba{sub 8}Ag{sub 4.4}Ge{sub 41.3{open_square}0.3}. Increasing the concentration of Ag causes the lattice parameters of the solid solution to increase linearly from a value of a = 1.0656 (x = 0, y = 3) to a = 1.0842 (x = 4.8, y = 0) nm. Site preference determination using X-ray refinement reveals that Ag atoms preferentially occupy the 6d site randomly mixed with Ge and vacancies, which become filled in the compound Ba{sub 8}Ag{sub 4.8}Ge{sub 41.2} when the Ag content increases. At 600 {sup o}C the phase region of the clathrate solution Ba{sub 8}Ag{sub x}Ge{sub 46-x-y{open_square}y} becomes separated from the Ba-Ge boundary and extends from 6.6 to 9.8 at.% Ag. The compound Ba{sub 6}Ge{sub 25} (clathrate type-{Iota}X) dissolves at 800 {sup o}C a maximum of 1.5 at.% Ag. The homogeneity regions of the two ternary compounds BaAg{sub 2-x}Ge{sub 2+x} (ThCr{sub 2}Si{sub 2}-type, 0.2 {<=} x {<=} 0.7) and Ba(Ag{sub 1-x}Ge{sub x}){sub 2} (AlB{sub 2}-type, 0.65 {<=} x {<=} 0.75) were established at 800 deg. C. Studies of transport properties for the series of Ba{sub 8}Ag{sub x}Ge{sub 46-x-y{open_square}y} compounds evidenced that electrons are the predominant charge carriers with the Fermi energy close to a gap. Its position can be fine-tuned by the substitution of Ge by Ag atoms and by mechanical processing of the starting material, Ba{sub 8}Ge{sub 43}. The proximity of the electronic structure at Fermi energy of Ba{sub 8}Ag{sub x}Ge{sub 46-x-y{open_square}y} to a gap is also corroborated by density

  18. Growth of BaSi2 continuous films on Ge(111) by molecular beam epitaxy and fabrication of p-BaSi2/n-Ge heterojunction solar cells

    Science.gov (United States)

    Takabe, Ryota; Yachi, Suguru; Tsukahara, Daichi; Toko, Kaoru; Suemasu, Takashi

    2017-05-01

    We grew BaSi2 films on Ge(111) substrates by various growth methods based on molecular beam epitaxy (MBE). First, we attempted to form BaSi2 films directly on Ge(111) by MBE without templates. We next formed BaSi2 films using BaGe2 templates as commonly used for MBE growth of BaSi2 on Si substrates. Contrary to our prediction, the lateral growth of BaSi2 was not promoted by these two methods; BaSi2 formed not into a continuous film but into islands. Although streaky patterns of reflection high-energy electron diffraction were observed inside the growth chamber, no X-ray diffraction lines of BaSi2 were observed in samples taken out from the growth chamber. Such BaSi2 islands were easily to get oxidized. We finally attempted to form a continuous BaSi2 template layer on Ge(111) by solid phase epitaxy, that is, the deposition of amorphous Ba-Si layers onto MBE-grown BaSi2 epitaxial islands, followed by post annealing. We achieved the formation of an approximately 5-nm-thick BaSi2 continuous layer by this method. Using this BaSi2 layer as a template, we succeeded in forming a-axis-oriented 520-nm-thick BaSi2 epitaxial films on Ge substrates, although (111)-oriented Si grains were included in the grown layer. We next formed a B-doped p-BaSi2(20 nm)/n-Ge(111) heterojunction solar cell. A wide-spectrum response from 400 to 2000 nm was achieved. At an external bias voltage of 1 V, the external quantum efficiency reached as high as 60%, demonstrating the great potential of BaSi2/Ge combination. However, the efficiency of a solar cell under AM1.5 illumination was quite low (0.1%). The origin of such a low efficiency was examined.

  19. Ca, Sr and Ba stable isotopes reveal the fate of soil nutrients along a tropical climosequence

    Science.gov (United States)

    Bullen, Thomas D.; Chadwick, Oliver A.

    2016-01-01

    Nutrient biolifting is an important pedogenic process in which plant roots obtain inorganic nutrients such as phosphorus (P) and calcium (Ca) from minerals at depth and concentrate those nutrients at the surface. Here we use soil chemistry and stable isotopes of the alkaline earth elements Ca, strontium (Sr) and barium (Ba) to test the hypothesis that biolifting of P has been an important pedogenic process across a soil climosequence developed on volcanic deposits at Kohala Mountain, Hawaii. The geochemical linkage between these elements is revealed as generally positive site-specific relationships in soil mass gains and losses, particularly for P, Ba and Ca, using the ratio of immobile elements titanium and niobium (Ti/Nb) to link individual soil samples to a restricted compositional range of the chemically and isotopically diverse volcanic parent materials. At sites where P is enriched in surface soils relative to abundances in deeper soils, the isotope compositions of exchangeable Ca, Sr and Ba in the shallowest soil horizons ( 10 cm depth) at those sites is consistently heavier than the volcanic parent materials. The isotope compositions of exchangeable Ca and Sr trend toward heavier compositions with depth more gradually, reflecting increasing leakiness from these soils in the order Ba < Sr < Ca and downward transfer of light biocycled Ca and Sr to deeper exchange sites. Given the long-term stability of ecosystem properties at the sites where P is enriched in surface soils, a simple box model demonstrates that persistence of isotopically light exchangeable Ca, Sr and Ba in the shallowest soil horizons requires that the uptake flux to plants from those near-surface layers is less than the recycling flux returned to the surface as litterfall. This observation implicates an uptake flux from an additional source which we attribute to biolifting. We view the heavy exchangeable Ba relative to soil parent values in deeper soils at sites where P is enriched in

  20. Structures, phase transitions and microwave dielectric properties of the 6H perovskites Ba3BSb2O9, B=Mg, Ca, Sr, Ba

    International Nuclear Information System (INIS)

    Ling, Chris D.; Rowda, Budwy; Avdeev, Maxim; Pullar, Robert

    2009-01-01

    We present a complete temperature-composition phase diagram for Ba 3 BSb 2 O 9 , B=Mg, Ca, Sr, Ba, along with their electrical behavior as a function of B. These compounds have long been recognized as 6H-type perovskites, but (with the exception of B=Mg) their exact structures and properties were unknown due to their low symmetries, temperature-dependent phase transitions, and difficulties in synthesizing pure samples. The full range of possible space group symmetries is observed, from ideal hexagonal P6 3 /mmc to monoclinic C2/c to triclinic P1-bar. Direct second-order transitions between these phases are plausible according to group theory, and no evidence was seen for any further intermediate phases. The phase diagram with respect to temperature and the effective ionic radius of B is remarkably symmetrical for B=Mg, Ca, and Sr. For B=Ba, a first-order phase transition to a locally distorted phase allows a metastable hexagonal phase to persist to lower temperatures than expected before decomposing around 600 K. Electrical measurements revealed that dielectric permittivity corrected for porosity does not change significantly as a function of B and is in a good agreement with the values predicted by the Clausius-Mossotti equation. - Graphical abstract: Thermodynamic phase diagram for Ba 3 BSb 2 O 9 , B=Mg, Ca, and Sr, as a function of temperature T and effective ionic radius (IR) of the B 2+ cation

  1. Local manifestations of a static magnetoelectric effect in nanostructured BaTiO3-BaFe12O9 composite multiferroics

    Science.gov (United States)

    Trivedi, Harsh; Shvartsman, Vladimir V.; Lupascu, Doru C.; Medeiros, Marco S. A.; Pullar, Robert C.; Kholkin, Andrei L.; Zelenovskiy, Pavel; Sosnovskikh, Andrey; Shur, Vladimir Ya.

    2015-02-01

    A study on magnetoelectric phenomena in the barium titanate-barium hexaferrite (BaTiO3-BaFe12O19) composite system, using high resolution techniques including switching spectroscopy piezoresponse force microscopy (SSPFM) and spatially resolved confocal Raman microscopy (CRM), is presented. It is found that both the local piezoelectric coefficient and polarization switching parameters change on the application of an external magnetic field. The latter effect is rationalized by the influence of magnetostrictive stress on the domain dynamics. Processing of the Raman spectral data using principal component analysis (PCA) and self-modelling curve resolution (SMCR) allowed us to achieve high resolution phase distribution maps along with separation of average and localized spectral components. A significant effect of the magnetic field on the Raman spectra of the BaTiO3 phase has been revealed. The observed changes are comparable with the classical pressure dependent studies on BaTiO3, confirming the strain mediated character of the magnetoelectric coupling in the studied composites.

  2. High-pressure BaCrO_3 polytypes and the 5H–BaCrO_2_._8 phase

    International Nuclear Information System (INIS)

    Arévalo-López, Angel M.; Paul Attfield, J.

    2015-01-01

    Polytypism of BaCrO_3 perovskites has been investigated at 900–1100 °C and pressures up to 22 GPa. Hexagonal 5H, 4H, and 6H perovskites are observed with increasing pressure, and the cubic 3C perovskite (a=3.99503(1) Å) is observed in bulk form for the first time at 19–22 GPa. An oxygen-deficient material with limiting composition 5H–BaCrO_2_._8 is synthesised at 1200 °C under ambient pressure. This contains double tetrahedral Cr"4"+ layers and orders antiferromagnetically below 260 K with a (0 0 1/2) magnetic structure. - Graphical abstract: Hexagonal 5H, 4H, and 6H perovskites polytypes of BaCrO_3 are observed with increasing pressure and the cubic 3C perovskite is stabilised in bulk form for the first time at 19–22 GPa. Oxygen-deficient 5H–BaCrO_2_._8 synthesised at ambient pressure contains double tetrahedral Cr"4"+ layers and orders antiferromagnetically below 260 K with a (0 0 1/2) magnetic structure.

  3. Solution based approaches for the morphology control of BaTiO3 particulates

    Directory of Open Access Journals (Sweden)

    Florentina Maxim

    2010-09-01

    Full Text Available Within the action COST 539 - ELENA our contribution was aimed at studying solution based approaches for the morphology control of BaTiO3 particulates. Initially, our kinetic analysis and systematic structural and morphological studies, demonstrated that during hydrothermal synthesis from layered titanate nanotubes (TiNTS, BaTiO3 forms via two mechanisms depending on the temperature and time. At low temperatures (90°C, “wild” type BaTiO3 dendritic particles with cubic structure were formed through a phase boundary topotactic reaction. At higher temperatures and/or for longer times time, the reaction is controlled by a dissolution precipitation mechanism and “seaweed” type BaTiO3 dendrites are formed. Our results unambiguously elucidated why TiNTs do not routinely act as templates for the formation of 1D BaTiO3.In our subsequent investigations, the effect of additives on the aqueous and hydrothermal synthesis of BaTiO3 was assessed. We reported that although the tested additives influenced the growth of BaTiO3, their behaviour varied; poly(acrylic acid (PAA adsorbed on specific crystallographic faces changing the growth kinetics and inducing the oriented attachment of the particles; poly(vinyl pyrrolidone (PVP, sodium dodecylsulfate (SDS and hydroxypropylmethylcellulose (HPMC act as growth inhibitors rather than crystal habit modifiers; and DFructose appeared to increase the activation energy for nucleation, resulting in small crystals (26 nm. Our work clearly indicates that the synthesis of 1D nanostructures of complex oxides by chemical methods is non trivial.

  4. In vitro anticancer potential of BaCO3 nanoparticles synthesized via green route.

    Science.gov (United States)

    Nagajyothi, P C; Pandurangan, Muthuraman; Sreekanth, T V M; Shim, Jaesool

    2016-03-01

    Green synthesis of nanoparticles is a growing research area because of their potential applications in nanomedicine. Barium carbonate nanoparticles (BaCO3 NPs) were synthesized using an aqueous extract of Mangifera indica seed as a reducing agent. These particles were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Transmission electron microscopy (TEM), selected area electron diffraction (SAED), Energy-dispersive-X-ray (EDX) and X-ray photoelectron spectroscopy (XPS) analysis. HR-TEM images are confirmed that green synthesized BaCO3 NPs have spherical, triangular and uneven shapes. EDX analysis confirmed the presence of Ba, C and O. The peaks at 2θ of 19.45, 23.90, 24.29, 27.72, 33.71, 34.08, 34.60, 41.98, 42.95, 44.18, 44.85, and 46.78 corresponding to (110), (111), (021), (002), (200), (112), (130), (221), (041), (202), (132) and (113) showed that BaCO3 NPs average size was ~18.3 nm. SAED pattern confirmed that BaCO3 NPs are crystalline nature. BaCO3 NPs significantly inhibited cervical carcinoma cells, as evidenced by cytotoxicity assay. Immunofluorescence and fluorescence assays showed that BaCO3 NPs increased the expression and activity of caspase-3, an autocatalytic enzyme that promotes apoptosis. According to the results, green synthesis route has great potential for easy, rapid, inexpensive, eco-friendly and efficient development of novel multifunctional nanoparticles for the treatment of cancer. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Synthesis, structure, optical property, and electronic structure of Ba7AgGa5Se15

    International Nuclear Information System (INIS)

    Yin, Wenlong; He, Ran; Feng, Kai; Hao, Wenyu; Yao, Jiyong; Wu, Yicheng

    2013-01-01

    Graphical abstract: -- Highlights: •A new quaternary chalcogenide Ba 7 AgGa 5 Se 15 was synthesized. •It adopts a new structure type in the space group P31c of the trigonal system. •The structure contains a three-dimensional framework built from GaSe 4 and AgSe 4 tetrahedra. •Ba 7 AgGa 5 Se 15 is a direct semiconductor with the band gap of 2.60 (2) eV. •The electronic structure was calculated to explain the optical properties. -- Abstract: A new quaternary chalcogenide Ba 7 AgGa 5 Se 15 was synthesized by solid state reaction. It crystallizes in a new structure type in the noncentrosymmetric space group P31c of the trigonal system. In the structure, three Ga2Se 4 tetrahedra and one Ga1Se 4 tetrahedron are connected to each other by corner-sharing to form [Ga 4 Se 10 ] 8− anion clusters, which are further connected to AgSe 4 tetrahedra by corner-sharing to form a three-dimensional framework with Ba, Se7, and isolated Ga3Se 4 tetrahedra residing in the cavities. The optical band gap of 2.60 (2) eV for Ba 7 AgGa 5 Se 15 was deduced from the diffuse reflectance spectrum. From a band structure calculation, Ba 7 AgGa 5 Se 15 is a direct semiconductor and the transition between Se and Ba plays an important role in the band gap

  6. Jumping the gun: Smoking constituent BaP causes premature primordial follicle activation and impairs oocyte fusibility through oxidative stress

    International Nuclear Information System (INIS)

    Sobinoff, A.P.; Pye, V.; Nixon, B.; Roman, S.D.; McLaughlin, E.A.

    2012-01-01

    Benzo(a)pyrene (BaP) is an ovotoxic constituent of cigarette smoke associated with pre-mature ovarian failure and decreased rates of conception in IVF patients. Although the overall effect of BaP on female fertility has been documented, the exact molecular mechanisms behind its ovotoxicity remain elusive. In this study we examined the effects of BaP exposure on the ovarian transcriptome, and observed the effects of in vivo exposure on oocyte dysfunction. Microarray analysis of BaP cultured neonatal ovaries revealed a complex mechanism of ovotoxicity involving a small cohort of genes associated with follicular growth, cell cycle progression, and cell death. Histomorphological and immunohistochemical analysis supported these results, with BaP exposure causing increased primordial follicle activation and developing follicle atresia in vitro and in vivo. Functional analysis of oocytes obtained from adult Swiss mice treated neonatally revealed significantly increased levels of mitochondrial ROS/lipid peroxidation, and severely reduced sperm-egg binding and fusion in both low (1.5 mg/kg/daily) and high (3 mg/kg/daily) dose treatments. Our results reveal a complex mechanism of BaP induced ovotoxicity involving developing follicle atresia and accelerated primordial follicle activation, and suggest short term neonatal BaP exposure causes mitochondrial leakage resulting in reduced oolemma fluidity and impaired fertilisation in adulthood. This study highlights BaP as a key compound which may be partially responsible for the documented effects of cigarette smoke on follicular development and sub-fertility. -- Highlights: ► BaP exposure up-regulates canonical pathways linked with follicular growth/atresia. ► BaP causes primordial follicle activation and developing follicle atresia. ► BaP causes oocyte mitochondrial ROS and lipid peroxidation, impairing fertilisation. ► Short term neonatal BaP exposure compromises adult oocyte quality.

  7. Anomalous Ba/Ca signals associated with low temperature stresses in Porites corals from Daya Bay, northern South China Sea

    Institute of Scientific and Technical Information of China (English)

    Tianran Chen; Kefu Yu; Shu Li; Tegu Chen; Qi Shi

    2011-01-01

    Barium to calcium (Ba/Ca) ratio in corals has been considered as a useful geochemical proxy for upwelling,river flood and other oceanic processes.However,recent studies indicated that additional environmental or biological factors can influence the incorporation of Ba into coral skeletons.In this study,Ba/Ca ratios of two Porites corals collected from Daya Bay,northern South China Sea were analyzed.Ba/Ca signals in the two corals were 'anomalous' in comparison with Ba behaviors seen in other near-shore corals influenced by upwelling or riverine runoff.Our Ba/Ca profiles displayed similar and remarkable patterns characterized by low and randomly fluctuating background signals periodically interrupted by sharp and large synchronous peaks,clearly indicating an environmental forcing.Further analysis indicated that the Ba/Ca profiles were not correlated with previously claimed environmental factors such as precipitation,coastal upwelling,anthropogenic activities or phytoplankton blooms in other areas.The maxima of Ba/Ca appeared to occur in the period of Sr/Ca maxima,coinciding with the winter minimum temperatures,which suggests that the anomalous high Ba/Ca signals were related to winter-time low sea surface temperature.We speculated that the Ba/Ca peaks in corals of the Daya Bay were most likely the results of enrichment of Ba-rich particles in their skeletons when coral polyps retracted under the stresses of anomalous winter low temperatures.In this case,Ba/Ca ratio in relatively high-latitude corals can be a potential proxy for tracing the low temperature stress.

  8. Jumping the gun: Smoking constituent BaP causes premature primordial follicle activation and impairs oocyte fusibility through oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Sobinoff, A.P.; Pye, V. [Reproductive Science Group, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW2308 (Australia); Nixon, B.; Roman, S.D. [Reproductive Science Group, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW2308 (Australia); ARC Centre of Excellence in Biotechnology and Development, University of Newcastle, Callaghan, NSW2308 (Australia); McLaughlin, E.A., E-mail: eileen.mclaughlin@newcastle.edu.au [Reproductive Science Group, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW2308 (Australia); ARC Centre of Excellence in Biotechnology and Development, University of Newcastle, Callaghan, NSW2308 (Australia)

    2012-04-01

    Benzo(a)pyrene (BaP) is an ovotoxic constituent of cigarette smoke associated with pre-mature ovarian failure and decreased rates of conception in IVF patients. Although the overall effect of BaP on female fertility has been documented, the exact molecular mechanisms behind its ovotoxicity remain elusive. In this study we examined the effects of BaP exposure on the ovarian transcriptome, and observed the effects of in vivo exposure on oocyte dysfunction. Microarray analysis of BaP cultured neonatal ovaries revealed a complex mechanism of ovotoxicity involving a small cohort of genes associated with follicular growth, cell cycle progression, and cell death. Histomorphological and immunohistochemical analysis supported these results, with BaP exposure causing increased primordial follicle activation and developing follicle atresia in vitro and in vivo. Functional analysis of oocytes obtained from adult Swiss mice treated neonatally revealed significantly increased levels of mitochondrial ROS/lipid peroxidation, and severely reduced sperm-egg binding and fusion in both low (1.5 mg/kg/daily) and high (3 mg/kg/daily) dose treatments. Our results reveal a complex mechanism of BaP induced ovotoxicity involving developing follicle atresia and accelerated primordial follicle activation, and suggest short term neonatal BaP exposure causes mitochondrial leakage resulting in reduced oolemma fluidity and impaired fertilisation in adulthood. This study highlights BaP as a key compound which may be partially responsible for the documented effects of cigarette smoke on follicular development and sub-fertility. -- Highlights: ► BaP exposure up-regulates canonical pathways linked with follicular growth/atresia. ► BaP causes primordial follicle activation and developing follicle atresia. ► BaP causes oocyte mitochondrial ROS and lipid peroxidation, impairing fertilisation. ► Short term neonatal BaP exposure compromises adult oocyte quality.

  9. Electrical conductivity and chemical stability of BaCe0· 8− xAxGd0 ...

    Indian Academy of Sciences (India)

    ... K. BaCe0.7In0.1Gd0.2O3− and BaCe0.7Zr0.1Gd0.2O3− ceramics exhibit an excellent chemical stability against boiling water. Indium is a suitable doping element to promote the sintering densification and to enhance both electrical conductivity and chemical stability of Gd-doped BaCeO3 at operating temperatures.

  10. Structural, optical and electronic properties of K2Ba(NO3)4 crystal

    Science.gov (United States)

    Isaenko, L. I.; Korzhneva, K. E.; Goryainov, S. V.; Goloshumova, A. A.; Sheludyakova, L. A.; Bekenev, V. L.; Khyzhun, O. Y.

    2018-02-01

    Nitrate crystals reveal nonlinear optical properties and could be considered as converters of laser radiation in the short-wave region. The conditions for obtaining and basic properties of K2Ba(NO3)4 double nitrate crystals were investigated. Crystal growth was implemented by slow cooling in the temperature range of 72-49 °C and low rate evaporation. The structural analysis of K2Ba(NO3)4 formation on the basis of two mixed simple nitrate structures is discussed. The main groups of oscillations in K2Ba(NO3)4 crystal were revealed using Raman and IR spectroscopy, and the table of vibrations for this compound was compiled. The electronic structure of K2Ba(NO3)4 was elucidated in the present work from both experimental and theoretical viewpoints. In particular, X-ray photoelectron spectroscopy (XPS) was employed in the present work to measure binding energies of the atoms constituting the titled compound and its XPS valence-band spectrum for both pristine and Ar+ ion-bombarded surfaces. Further, total and partial densities of states of constituent atoms of K2Ba(NO3)4 have been calculated. The calculations reveal that the O 2p states dominate in the total valence-band region of K2Ba(NO3)4 except of its bottom, where K 3p and Ba 5p states are the principal contributors, while the bottom of the conduction band is composed mainly of the unoccupied O 2p states, with somewhat smaller contributions of the N 2p∗ states as well. With respect to the occupation of the valence band by the O 2p states, the present band-structure calculations are confirmed by comparison on a common energy scale of the XPS valence-band spectrum and the X-ray emission O Kα band for the K2Ba(NO3)4 crystal under study. Furthermore, the present calculations indicate that the K2Ba(NO3)4 compound is a direct-gap material.

  11. Preparation, photoluminescent properties and luminescent dynamics of BaAlF5:Eu2+ nanophosphors

    International Nuclear Information System (INIS)

    Zhang, Wei; Hua, Ruinian; Liu, Tianqing; Zhao, Jun; Na, Liyan; Chen, Baojiu

    2014-01-01

    Graphical abstract: Rice-shaped BaAlF 5 :Eu 2+ nanophosphors were synthesized via one-pot hydrothermal process. The as-prepared BaAlF 5 :Eu 2+ are composed of many particles with an average diameter of 40 nm. When excited at 260 nm, the sharp line emission located at 361 nm of Eu 2+ was observed. The optimum doping concentration of Eu 2+ was confirmed to be 5 mol%. The strong ultraviolet emission of Eu 2+ ions in BaAlF 5 :Eu 2+ nanoparticles suggests that these nanoparticles may have potential applications for sensing, solid-state lasers and spectrometer calibration. - Highlights: • BaAlF 5 :Eu 2+ nanophosphors were synthesized via a mild hydrothermal process. • The Van and Huang models were used to research the mechanism of concentration quenching. • The optimum doping concentration of Eu2+ was confirmed to be 5 mol%. - Abstract: Eu 2+ -doped BaAlF 5 nanophosphors were synthesized via a facile one-pot hydrothermal method. The final products were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and photoluminescence (PL) spectroscopy. XRD results showed that the prepared samples are single-phase. The FE-SEM and TEM images indicated that the prepared BaAlF 5 :Eu 2+ nanophosphors are composed of many rice-shaped particles with an average diameter of 40 nm. When excited at 260 nm, BaAlF 5 :Eu 2+ nanophosphors exhibit the sharp line emissions of Eu 2+ at room temperature. The optimum doping concentration of Eu 2+ was confirmed to be 5 mol%. The Van and Huang models were used to study the mechanism of concentration quenching and the electric dipole–dipole interaction between Eu 2+ can be deduced to be a dominant for quenching fluorescence in BaAlF 5 :Eu 2+ nanophosphors. The strong ultraviolet emission of Eu 2+ in BaAlF 5 :Eu 2+ nanophosphors suggests that these nanoparticles may have potential applications for sensing, spectrometer calibration and solid-state lasers

  12. Oxygen excess in the '114' cobaltite hexagonal structure: The ferrimagnet CaBaCo4O7.50

    International Nuclear Information System (INIS)

    Pralong, V.; Caignaert, V.; Sarkar, T.; Lebedev, O.I.; Duffort, V.; Raveau, B.

    2011-01-01

    The study of the oxidation of the '114' orthorhombic cobaltite CaBaCo 4 O 7 , using first electrochemistry and then soft chemistry based on oxidation by NaClO, has allowed a new phase, CaBaCo 4 O 7.50 , to be prepared topotactically. The structural study of this phase shows that its hexagonal structure, closely related to that of orthorhombic CaBaCo 4 O 7 , is curiously similar to that of the members of the LnBaCo 4 O 7 series, in spite of its excess oxygen. Its magnetic study shows that this phase, like CaBaCo 4 O 7 , is ferrimagnetic with the same T C (60 K), but differently exhibits an unusual magnetic hysteresis. This exceptional behavior of CaBaCo 4 O 7 with respect to oxidation as well as the magnetic properties of CaBaCo 4 O 7.50 is interpreted in terms of the presence of defects due to oxidation. - Graphical Abstract: The study of the oxidation of the '114' orthorhombic cobaltite CaBaCo 4 O 7 , using first electrochemistry and then soft chemistry based on oxidation by NaClO, has allowed a new phase, CaBaCo 4 O 7.50 , to be prepared topotactically. The structural study of this phase shows that its hexagonal structure, closely related to that of orthorhombic CaBaCo 4 O 7 , is curiously similar to that of the members of the LnBaCo 4 O 7 series, in spite of its oxygen excess. Its magnetic study shows that this phase, like CaBaCo 4 O 7 , is ferrimagnetic. Highlights: → Topotactic oxidation by means of electrochemistry and soft chemistry of the '114' orthorhombic cobaltite CaBaCo 4 O 7 . → This new phase, CaBaCo 4 O 7.5 shows an hexagonal structure, is closely related to that of orthorhombic mother phase CaBaCo 4 O 7 . → CaBaCo 4 O 7.5 is ferrimagnetic and exhibits an unusual magnetic hysteresis, due to defect pinning centers.

  13. Investigation of BaMoO4-Ln2(MoO4)3 systems (Ln = Nd, Sm, Yb)

    International Nuclear Information System (INIS)

    Vakulyuk, V.V.; Evdokimov, A.A.; Khomchenko, G.P.

    1982-01-01

    Using the methods of X-ray phase and differential-thermal analyses phase ratios in the systems BaMoO 4 -Ln 2 (MoO 4 ) 3 (Ln=Nd, Sm, Yb); BaNd 2 (MoO 4 ) 4 -MaGd 2 (MoO 4 ) are studied. Unit cell parameters and the character of melting of the compounds BaLn 2 (MoO 4 ) 4 are specified. Effect of growth conditions on laminated nature of BaGd 2 (MoO 4 ) 4 monocrystals is studied

  14. New anisotropic rare earth fluorides BaR2F8(R=Y,Dy-Lu): growth and characterization

    International Nuclear Information System (INIS)

    Kaminskii, A.A.; Butashin, A.V.; Sulyanov, S.N.; Bagayev, S.N.; Eichler, H.J.; Findeisen, J.; Liu, B.; Taeuber, U.; Peuser, P.

    1998-01-01

    Polymorphism of BaR 2 F 8 compounds is analyzed, and some peculiarities of the crystal growth from the melt are discussed. We report on the orthorhombic BaLu 2 F 8 crystal with ordered structure, a new crystalline material for generating Ln 3+ activator ions. Spectroscopic and laser characteristics of Nd 3+ - and Er 3+ -doped BaLu 2 F 8 samples are discussed as representative examples. Besides, we pay special attention to monoclinic BaY 2 F 8 :Er 3+ crystals, as active media for highly efficient CW 3 μm laser-diode pumped lasers. (orig.)

  15. Impacts of Mining and Urbanization on the Qin-Ba Mountainous Environment, China

    Directory of Open Access Journals (Sweden)

    Xinliang Xu

    2016-05-01

    Full Text Available The Qin-Ba Ecological Functional Zone is a component of China’s ecological security pattern designed to protect the regional ecosystem and maintain biodiversity. However, due to the impact of mining and urban encroachment, the plight of a sustainable ecosystem in the Qin-Ba mountainous area is deteriorating. This paper has used a remote sensing and geographic information system (GIS to examine the impacts of mining and urban encroachment on the environment in the Qin-Ba mountainous area. The results indicate that the total mined area in 2013 was 22 km2 and is predicted to escalate. Results also show that the ecosystems in Fengxian County, Shaanxi Province and Baokang County, Hubei Province were most severely affected by mining. Urbanization in the Qin-Ba mountainous area has seen an increase of 85.58 km2 in urban land use from 2010 to 2013. In addition, infrastructure development including airport construction, tourism resorts and real estate development in the Qin-Ba mountainous area has intensified environmental and biodiversity disturbances since large areas of forest have been cleared. Our results should provide insight and assistance to city planners and government officials in making informed decisions.

  16. Consequences of Ca multisite occupation for the conducting properties of BaTiO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Zulueta, Y.A., E-mail: yohandysalexis.zuluetaleyva@student.kuleuven.be [Departamento de Física, Facultad de Ciencias Naturales, Universidad de Oriente, CP-90500 Santiago de Cuba (Cuba); Department of Chemistry, KU Leuven, B-3001 Leuven (Belgium); Dawson, J.A. [Department of Engineering, University of Cambridge, Cambridge CB2 1PZ (United Kingdom); Leyet, Y. [Departamento de Engenharia de Materiais, Universidade Federal do Amazonas, Av. General Rodrigo Otávio, 6200 – Coroado I, 69077-000 Manaus (Brazil); Departamento de Física, Universidade Federal do Amazonas, Av. General Rodrigo Otávio, 6200 – Coroado I, 69077-000 Manaus, Amazonas (Brazil); Anglada-Rivera, J. [Instituto Federal de Educação Ciência e Tecnologia do Amazonas, Av. 7de Setembro, 1975, 69020-120 Manaus (Brazil); Guerrero, F. [Departamento de Física, Universidade Federal do Amazonas, Av. General Rodrigo Otávio, 6200 – Coroado I, 69077-000 Manaus, Amazonas (Brazil); Silva, R.S. [Departamento de Física, Universidade Federal de Sergipe, 49100-000 São Cristóvão, SE (Brazil); Nguyen, Minh Tho [Department of Chemistry, KU Leuven, B-3001 Leuven (Belgium)

    2016-11-15

    In combination with the dielectric modulus formalism and theoretical calculations, a newly developed defect incorporation mode, which is a combination of the standard A- and B-site doping mechanisms, is used to explain the conducting properties in 5 mol% Ca-doped BaTiO{sub 3}. Simulation results for Ca solution energies in the BaTiO{sub 3} lattice show that the new oxygen vacancy inducing mixed mode exhibits low defect energies. A reduction in dc conductivity compared with undoped BaTiO{sub 3} is witnessed for the incorporation of Ca. The conducting properties of 5 mol% Ca-doped BaTiO{sub 3} are analyzed using molecular dynamics and impedance spectroscopy. The ionic conductivity activation energies for each incorporation mode are calculated and good agreement with experimental data for oxygen migration is observed. The likely existence of the proposed defect configuration is also analyzed on the basis of these methods. - Graphical abstract: Oxygen vacancy formation as a result of self-compensation in Ca-doped BaTiO{sub 3}.

  17. Colloidal synthesis of BaF2 nanoparticles and their application as fillers in polymer nanocomposites

    Science.gov (United States)

    Sathyamurthy, Srivatsan; Tuncer, Enis; More, Karren L.; Gu, Baohua; Sauers, Isidor; Paranthaman, M. Parans

    2012-03-01

    Nanoparticles of pure and Eu-doped BaF2 have been prepared through sol-gel colloidal synthesis. In addition, BaF2-filled PMMA polymer nanocomposites were fabricated and dielectric properties were measured. The as-synthesized pure and Eu-doped BaF2 nanoparticles were analyzed by both X-ray diffraction and transmission electron microscopy and consisted of crystalline BaF2 particles with an average diameter of 13.6 nm with a standard deviation of about ±2.4 nm. The photoluminescence properties of the pure and Eu-doped (2%, 4% and 8%) nanoparticles showed characteristic emission of Eu3+ (5D0→7F J ( J=1-4) transitions). We also measured significantly enhanced dielectric breakdown strength of up to 30% for BaF2 nanocomposites over the unfilled PMMA polymer. This study thus offers some promise of sol-gel synthesis of nanocomposite dielectrics with great potential for use as electrical insulation materials in cryogenic high-voltage applications.

  18. Colloidal synthesis of BaF2 nanoparticles and their application as fillers in polymer nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Sathyamurthy, Srivatsan [ORNL; Tuncer, Enis [ORNL; More, Karren Leslie [ORNL; Gu, Baohua [ORNL; Sauers, Isidor [ORNL; Paranthaman, Mariappan Parans [ORNL

    2012-01-01

    Nanoparticles of pure and Eu-doped BaF2 have been prepared through sol-gel colloidal synthesis. In addition, BaF2 filled PMMA polymer nanocomposites were fabricated and dielectric properties were measured. The as-synthesized pure and Eu-doped BaF2 nanoparticles were analyzed by both X-ray diffraction and transmission electron microscopy and consisted of crystalline BaF2 particles with an average diameter of 13.6 nm with a standard deviation of about 2.4 nm. The photoluminescence properties of the pure and Eu-doped (2%, 4% and 8%) nanoparticles showed characteristic emission of Eu3+ (5D0 7FJ (J=1-4) transitions). We also measured significantly enhanced dielectric breakdown strength of up to 30% for BaF2 nanocomposites over the unfilled PMMA polymer. This study thus offers some promise of sol-gel synthesis of nanocomposite dielectrics with great potential for use as electrical insulation materials in cryogenic high voltage applications.

  19. Crystal structures of the double perovskites Ba2Sr1-x Ca x WO6

    International Nuclear Information System (INIS)

    Fu, W.T.; Akerboom, S.; IJdo, D.J.W.

    2007-01-01

    Structures of the double perovskites Ba 2 Sr 1- x Ca x WO 6 have been studied by the profile analysis of X-ray diffraction data. The end members, Ba 2 SrWO 6 and Ba 2 CaWO 6 , have the space group I2/m (tilt system a 0 b - b - ) and Fm3-barm (tilt system a 0 a 0 a 0 ), respectively. By increasing the Ca concentration, the monoclinic structure transforms to the cubic one via the rhombohedral R3-bar phase (tilt system a - a - a - ) instead of the tetragonal I4/m phase (tilt system a 0 a 0 c - ). This observation supports the idea that the rhombohedral structure is favoured by increasing the covalency of the octahedral cations in Ba 2 MM'O 6 -type double perovskites, and disagrees with a recent proposal that the formation of the π-bonding, e.g., d 0 -ion, determines the tetragonal symmetry in preference to the rhombohedral one. - Graphical abstract: Enlarged sections showing the evolution of the basic (222) and (400) reflections in Ba 2 Sr 1- x Ca x WO 6 . Tick marks below are the positions of Bragg's reflections calculated using the space groups I2/m (x=0), R3-bar (x=0.25, 0.5 and 0.75) and Fm3-barm (x=1), respectively

  20. Hybrid molecular beam epitaxy for the growth of stoichiometric BaSnO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Prakash, Abhinav, E-mail: praka019@umn.edu; Dewey, John; Yun, Hwanhui; Jeong, Jong Seok; Mkhoyan, K. Andre; Jalan, Bharat, E-mail: bjalan@umn.edu [Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2015-11-15

    Owing to its high room-temperature electron mobility and wide bandgap, BaSnO{sub 3} has recently become of significant interest for potential room-temperature oxide electronics. A hybrid molecular beam epitaxy (MBE) approach for the growth of high-quality BaSnO{sub 3} films is developed in this work. This approach employs hexamethylditin as a chemical precursor for tin, an effusion cell for barium, and a radio frequency plasma source for oxygen. BaSnO{sub 3} films were thus grown on SrTiO{sub 3} (001) and LaAlO{sub 3} (001) substrates. Growth conditions for stoichiometric BaSnO{sub 3} were identified. Reflection high-energy electron diffraction (RHEED) intensity oscillations, characteristic of a layer-by-layer growth mode were observed. A critical thickness of ∼1 nm for strain relaxation was determined for films grown on SrTiO{sub 3} using in situ RHEED. Scanning transmission electron microscopy combined with electron energy-loss spectroscopy and energy dispersive x-ray spectroscopy confirmed the cube-on-cube epitaxy and composition. The importance of precursor chemistry is discussed in the context of the MBE growth of BaSnO{sub 3}.

  1. Recent progress in material technology on RE-Ba-Cu-O bulk superconductors

    International Nuclear Information System (INIS)

    Teshima, Hidekazu; Morita, Mitsuru

    2011-01-01

    The current status of large-grained RE-Ba-Cu-O (RE: Y or rare earth elements) bulk superconductors with excellent superconducting properties is described. Gd-Ba-Cu-O bulk superconductors can trap a very high magnetic field even if they are melt-processed in air. Although the electromagnetic force caused by the trapped field is larger for a larger sample and may break the sample, a large sample of Gd-Ba-Cu-O 46 mm in diameter has the potential of trapped magnetic fields greater than 10 T at around 40 K. In addition, single-grained bulk superconductors as large as 150 mm can be obtained using the RE compositional gradient method. Dy-Ba-Cu-O is an ideal material for current leads because it has low thermal conductivity and high critical current density at 77 K in high magnetic fields. Eu-Ba-Cu-O has low magnetic permeability, and is therefore suitable for bulk NMR applications. Progress in machining technology has made possible various bulk superconductors with complicated shapes such as coils, leading to small and strong electromagnets by stacking several coil-shaped bulk superconductors together. (author)

  2. Large linear magnetoresistance in a new Dirac material BaMnBi2

    Science.gov (United States)

    Wang, Yi-Yan; Yu, Qiao-He; Xia, Tian-Long

    2016-10-01

    Dirac semimetal is a class of materials that host Dirac fermions as emergent quasi-particles. Dirac cone-type band structure can bring interesting properties such as quantum linear magnetoresistance and large mobility in the materials. In this paper, we report the synthesis of high quality single crystals of BaMnBi2 and investigate the transport properties of the samples. BaMnBi2 is a metal with an antiferromagnetic transition at T N = 288 K. The temperature dependence of magnetization displays different behavior from CaMnBi2 and SrMnBi2, which suggests the possible different magnetic structure of BaMnBi2. The Hall data reveals electron-type carriers and a mobility μ(5 K) = 1500 cm2/V·s. Angle-dependent magnetoresistance reveals the quasi-two-dimensional (2D) Fermi surface in BaMnBi2. A crossover from semiclassical MR ˜ H 2 dependence in low field to MR ˜ H dependence in high field, which is attributed to the quantum limit of Dirac fermions, has been observed in magnetoresistance. Our results indicate the existence of Dirac fermions in BaMnBi2. Project supported by the National Natural Science Foundation of China (Grant No. 11574391), the Fundamental Research Funds for the Central Universities, and the Research Funds of Renmin University of China (Grant No. 14XNLQ07).

  3. Large linear magnetoresistance in a new Dirac material BaMnBi2

    International Nuclear Information System (INIS)

    Wang Yi-Yan; Yu Qiao-He; Xia Tian-Long

    2016-01-01

    Dirac semimetal is a class of materials that host Dirac fermions as emergent quasi-particles. Dirac cone-type band structure can bring interesting properties such as quantum linear magnetoresistance and large mobility in the materials. In this paper, we report the synthesis of high quality single crystals of BaMnBi 2 and investigate the transport properties of the samples. BaMnBi 2 is a metal with an antiferromagnetic transition at T N = 288 K. The temperature dependence of magnetization displays different behavior from CaMnBi 2 and SrMnBi 2 , which suggests the possible different magnetic structure of BaMnBi 2 . The Hall data reveals electron-type carriers and a mobility μ (5 K) = 1500 cm 2 /V·s. Angle-dependent magnetoresistance reveals the quasi-two-dimensional (2D) Fermi surface in BaMnBi 2 . A crossover from semiclassical MR ∼ H 2 dependence in low field to MR ∼ H dependence in high field, which is attributed to the quantum limit of Dirac fermions, has been observed in magnetoresistance. Our results indicate the existence of Dirac fermions in BaMnBi 2 . (rapid communication)

  4. Compounds of type Ba/sub 2/Bsup(III)Ossup(V)O/sub 6/

    Energy Technology Data Exchange (ETDEWEB)

    Treiber, U; Kemmler-Sack, S [Tuebingen Univ. (Germany, F.R.). Lehrstuhl fuer Anorganische Chemie 2

    1981-07-01

    The black perovskites of type Ba/sub 2/Bsup(III)Ossup(V)O/sub 6/ crystallize cubic (Bsup(III) = Pr, Nd, Sm-Lu, Y) and rhombohedral (Bsup(III) = La) respectively; the cell volumina decrease linearily with (rsub(B)sup(III))/sup 3/. Intensity calculations on powder data for Ba/sub 2/YOsO/sub 6/ (space group Fm3m-Osub(h)/sup 5/) and Ba/sub 2/LaOsO/sub 6/ (space group R-3m-Dsub(3d)/sup 5/) gave the intensity related R'values of 4.6% and 5.0% respectively. The results of the vibrational spectroscopic investigations are reported in common with the bond orders, M-O distances and mean amplitudes and compared with the corresponding values of the series Ba/sub 2/Bsup(III)Irsup(V)O/sub 6/ and Ba/sub 2/Bsup(III)Rusup(V)O/sub 6/.

  5. Precipitation method for barium metaborate (BaB2O4) synthesis from borax solution

    International Nuclear Information System (INIS)

    Akşener, Eymen; Figen, Aysel Kantürk; Pişkin, Sabriye

    2013-01-01

    In this study, barium metaborate (BaB 2 O 4 , BMB) synthesis from the borax solution was carried out. BMB currently is used in production of ceramic glazes, luminophors, oxide cathodes as well as additives to pigments for aqueous emulsion paints and also β−BaB 2 O 4 single crystals are the best candidate for fabrication of solid-state UV lasers operating at a wavelength of 200 nm due to excellent nonlinear optical properties. In the present study, synthesis was carried out from the borax solution (Na 2 B 4 O 7⋅ 10H 2 O, BDH) and barium chloride (BaCI 2⋅ 2H 2 O, Ba) in the glass-batch reactor with stirring. The effect of, times (5-15 min), molar ratio [stoich.ration (1.0:2.0), 1.25:2.0, 1.5:2.0, 2.5:2:0, 3.0:2.0, 3.5:2.0,4.0:2.0, 5.0:2.0] and also crystallization time (2-6 hour) on the BMB yield (%) was investigated at 80 °C reaction temperature. It is found that, BMB precipitation synthesis with 90 % yield can be performed from 0.50 molar ration (BDH:Ba), under 80 °C, 15 minute, and 6 hours crystallization time. The structural properties of BMB powders were characterized by using XRD, FT-IR and DTA-TG instrumental analysis technique

  6. Precipitation method for barium metaborate (BaB2O4) synthesis from borax solution

    Science.gov (United States)

    Akşener, Eymen; Figen, Aysel Kantürk; Pişkin, Sabriye

    2013-12-01

    In this study, barium metaborate (BaB2O4, BMB) synthesis from the borax solution was carried out. BMB currently is used in production of ceramic glazes, luminophors, oxide cathodes as well as additives to pigments for aqueous emulsion paints and also β-BaB2O4 single crystals are the best candidate for fabrication of solid-state UV lasers operating at a wavelength of 200 nm due to excellent nonlinear optical properties. In the present study, synthesis was carried out from the borax solution (Na2B4O7ṡ10H2O, BDH) and barium chloride (BaCI2ṡ2H2O, Ba) in the glass-batch reactor with stirring. The effect of, times (5-15 min), molar ratio [stoich.ration (1.0:2.0), 1.25:2.0, 1.5:2.0, 2.5:2:0, 3.0:2.0, 3.5:2.0,4.0:2.0, 5.0:2.0] and also crystallization time (2-6 hour) on the BMB yield (%) was investigated at 80 °C reaction temperature. It is found that, BMB precipitation synthesis with 90 % yield can be performed from 0.50 molar ration (BDH:Ba), under 80 °C, 15 minute, and 6 hours crystallization time. The structural properties of BMB powders were characterized by using XRD, FT-IR and DTA-TG instrumental analysis technique.

  7. Impedance spectroscopy of Li2CO3 doped (Ba,Sr)TiO3 ceramic

    Science.gov (United States)

    Ham, Yong-Su; Koh, Jung-Hyuk

    2013-02-01

    (BaxSr1-x)TiO3-based ceramic has been considered as one of the most important electronic materials widely employed in microwave passive device applications. Many researches have been performed to lower the high sintering temperature, by adding various dopants such as B2O3, La2O3, etc. In our previous study, by adding Li2CO3 to (Ba0.5,Sr0.5)TiO3 ceramics, the sintering temperature of Li2CO3 doped (Ba0.5,Sr0.5)TiO3 ceramics decreased from 1350 to 900 °C. This study observed the crystalline structure and electrical properties of Li2CO3 doped (Ba0.5,Sr0.5)TiO3 ceramics. In scanning the crystalline structure of Li2CO3 doped (Ba0.5,Sr0.5)TiO3 ceramics, no pyro phase was observed by X-ray diffraction analysis. To investigate the electrical properties of Li2CO3 doped (Ba0.5,Sr0.5)TiO3 ceramics, real and imaginary parts of the impedances were analyzed. Complex impedance data were measured from 100 Hz to 1 MHz at various temperature ranges.

  8. BaFCl:Eu2+, a new phosphor for X-ray-intensifying screens

    International Nuclear Information System (INIS)

    Stevels, A.L.N.; Pingault, F.

    1975-01-01

    A number of phosphors for X-ray-intensifying screens have been evaluated by calculating figures of merit. On use in combination with standard (''blue''-sensitive) X-ray film, BaFCl:Eu 2+ and BaFBr:Eu 2+ give better performance than the traditional CaWO 4 and more recently developed UV or blue-emitting materials (e.g., sulphates and y-oxysulphides). The calculated figures of merit of BaFCl:Eu 2+ or BaFBr:Eu 2+ /standard-film combinations are comparable to those of Gd 2 O 2 S:Tb/green-sensitive X-ray film systems. The preparation of optimal fluorohalide:Eu 2+ phosphors involves proper formation of the host lattice, complete reduction of Eu 3+ ions as well as elimination of afterglow. Measurements on powders and experimental screens indicate that by using BaFCl:Eu 2+ screens in radiography, important dose reductions can be achieved without the necessity of using other than standard (''blue''-sensitive) X-ray films

  9. Accurate projected augmented wave datasets for BaFe2As2

    International Nuclear Information System (INIS)

    Cao Chao; Wu Yuing; Hamdan, Rashid; Wang, Yunpeng; Cheng Haiping

    2010-01-01

    By carefully choosing parameters and including more semi-core orbitals as valence electrons, we have constructed a high-quality projected augmented wave dataset that yields results comparable to existing full-potential linearized augmented plane-wave calculations. The dataset was then applied to BaFe 2 As 2 to study the effects of different levels of structure optimization, as well as different choices of exchange-correlation functionals. It was found that the local density approximation exchange-correlation functional fails to find the correct spin-density-wave anti-ferromagnetic (SDW-AFM) ground state under full optimization, while the Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional obtains the correct state but significantly overestimates the magnetism. The electronic structure of the SDW-AFM state is not very sensitive to structure optimizations with the PBE exchange-correlation functional because the positions of the As atoms are preserved under optimizations. We further investigated the Ba atom diffusion process on the BaFe 2 As 2 surface using the nudged elastic bands method. The Ba atom was found to be stable above the center of the squares formed by the surface As atoms, and a diffusion barrier of 1.2 eV was found. Our simulated scanning tunneling microscopy image suggests an ordered surface Ba atom structure, in agreement with Massee et al (2009 Phys. Rev. B 80 140507; van Heumen E et al 2010 arXiv:1009.3493v1).

  10. Ion conductivities of ZrF4-BaF2-CsF glasses

    International Nuclear Information System (INIS)

    Kawamoto, Yoji; Nohara, Ichiro

    1987-01-01

    The glass-forming region in the ZrF 4 -BaF 2 -CsF glass system has been determined and the ac conductivity and the transport number of fluoride ions have been measured. The conductivities of compounds β-Cs 2 ZrF 6 , α-SrZrF 6 , α-BaZrF 6 , β-BaZrF 6 and α-PbZrF 6 have also been measured. These results and a previous study of ZrF 4 -BaF 2 -MF n (M: the groups I-IV metals) glasses revealed the following: (1) the ZrF 4 -BaF 2 -CsF glasses are exclusively fluoride-ion conductors; (2) the ionic conductivities of ZrF 4 -based glasses are predominantly determined by the activation energies for conduction; (3) the activation energy for conduction decreases with an increase in the average polarizability of glass-constituting cations; (4) a decrease in average Zr-F bond length and a lowering of the average F coordination number of Zr are presumed to increase the activation energy for conduction. Principles of developing ZrF 4 -based glasses with higher conductivities have also been proposed. (Auth.)

  11. Advances in enlargement of melt-textured Gd-Ba-Cu-O superconductors

    International Nuclear Information System (INIS)

    Nariki, S; Sakai, N; Kita, M; Fujikura, M; Murakami, M; Hirabayashi, I

    2006-01-01

    We investigated the fabrication of melt-textured Gd-Ba-Cu-O bulk superconductors with the employment of a Gd 2 BaO 4 (Gd210)-BaCuO 2 -CuO precursor. This enabled us to synthesize a very large Gd-Ba-Cu-O bulk superconductor, 140 mm in diameter. The trapped field distribution measured at 77 K revealed that the sample had no serious cracks, and the maximum field was 2.3 T. The formation behaviour and depressing mechanism of cracking were studied using sintered Gd210-containing precursors. The Ba-Cu-O component in the precursor melted at around 900 deg. C. The formation of such a liquid phase enhanced the densification of the precursor by liquid phase sintering. The mechanical strength of the sintered precursor was increased compared to the conventional Gd123-Gd211 precursor. This will be effective in preventing crack formation in the texturing process of large single-grain samples. The superconducting properties of the bulk sample fabricated from Gd210-containing precursor have been discussed

  12. Electronic structures of PrBa2Cu3O7, Pr2Ba4Cu7O15-y(y=0,1), and PrBa2Cu4O8 based on LSDA+U method

    International Nuclear Information System (INIS)

    Tavana, A.; Shirazi, M.; Akhavan, M.

    2009-01-01

    The electronic structures of PrBa 2 Cu 3 O 7 (Pr123), Pr 2 Ba 4 Cu 7 O 15-y (Pr247), and PrBa 2 Cu 4 O 8 (Pr124) cuprates have been obtained using density-functional theory in the local spin density approximation plus onsite Coulomb interaction (LSDA+U). Onsite Hubbard correlation, U, has been considered for Pr-f and Cu-d orbitals and the effects of considering these correlation corrections on the Pr-O hybridizations have been inspected. Results imply that the Pr ionization state in Pr123 system is constituted from two different configurations, and the energy of the f states in these two configurations has an important role in superconductivity properties of the system. Our calculations also show that in both Pr124 and Pr247 systems, suppression of superconductivity is weaker than that in the Pr123 system. This occurs due to the weaker Pr-O bond in both Pr124 and Pr247 systems. The role of the double chain and single chain on the conduction properties of these compounds has been investigated. We have also studied the effect of oxygen deficiency in Pr247 system, which seems to revive superconductivity in this system. Investigating the hole carriers in the CuO 2 plane shows a correlation between superconductivity suppression and hole decrement in the planes. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  13. Structural characterization of a new vacancy ordered perovskite modification found for Ba3Fe3O7F (BaFeO2.333F0.333): Towards understanding of vacancy ordering for different perovskite-type ferrites

    International Nuclear Information System (INIS)

    Clemens, Oliver

    2015-01-01

    The new vacancy ordered perovskite-type compound Ba 3 Fe 3 O 7 F (BaFeO 2.33 F 0.33 ) was prepared by topochemical low-temperature fluorination of Ba 2 Fe 2 O 5 (BaFeO 2.5 ) using stoichiometric amounts of polyvinylidene difluoride (PVDF). The vacancy order was found to be unique so far for perovskite compounds, and the connectivity pattern can be explained by the formula Ba 3 (FeX 6/2 ) (FeX 5/2 ) (FeX 3/2 X 1/1 ), with X=O/F. Mössbauer measurements were used to confirm the structural analysis and agree with the presence of Fe 3+ in the above mentioned coordination environments. Group–subgroup relationships were used to build a starting model for the structure solution and to understand the relationship to the cubic perovskite structure. Furthermore, a comparison of a variety of vacancy-ordered iron-containing perovskite-type structures is given, highlighting the factors which favour one structure type over the other depending on the composition. - Graphical abstract: The crystal structure of Ba 3 Fe 3 O 7 F in comparison to other perovskite type ferrites. - Highlights: • The crystal structure of Ba 3 Fe 3 O 7 F in comparison to other perovskite type ferrites. • Ba 3 Fe 3 O 7 F was synthesized by low temperature fluorination of Ba 2 Fe 2 O 5 . • Ba 3 Fe 3 O 7 F shows a unique vacancy order not found for other perovskite type compounds. • The structure of Ba 3 Fe 3 O 7 F was solved using group–subgroup relationships. • A systematic comparison to other ferrite type compounds reveals structural similarities and differences. • The A-site coordination of the cation is shown to play an important role for the type of vacancy order found

  14. X-ray photoelectron spectroscopy study on Ba1-xEuxTiO3

    International Nuclear Information System (INIS)

    Lu, D.-Y.; Sugano, Mikio; Sun Xiuyun; Su Wenhui

    2005-01-01

    X-ray photoelectron spectroscopy is employed to study inner-shell core-level binding energies Eu 4d, Ti 2p and O 1s, Ba 3d for new single-phase Ba 1-x Eu x TiO 3 (0.1 ≤ x ≤ 0.4) samples prepared by solid state reaction at 4.0 GPa and 1090 deg. C. The peak positions of binding energies determined by linear background subtraction and Gaussian fit are presented. XPS analysis indicates that the mixed-valent Eu 3+ /Eu 2+ ions at A-site and Ti 4+ /Ti 3+ ions at B-site coexisted in the Ba 1-x Eu x TiO 3 powder surface, and the amount of Eu 2+ ions is equal to Eu 3+ ions

  15. Compensation mechanisms at high temperature in Y-doped BaTiO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Paredes-Olguin, M., E-mail: myriampaol@gmail.com [Department of Metallurgical and Materials Engineering, ESIQIE National Polytechnic Institute, U.P.A. Lopez Mateos, Zacatenco, Mexico City 07738 (Mexico); Lira-Hernandez, I.A.; Gomez-Yanez, C. [Department of Metallurgical and Materials Engineering, ESIQIE National Polytechnic Institute, U.P.A. Lopez Mateos, Zacatenco, Mexico City 07738 (Mexico); Espino-Cortes, F.P. [Department of Electrical Engineering, SEPI-ESIME National Polytechnic Institute, U.P.A. Lopez Mateos, Zacatenco, Mexico City 07738 (Mexico)

    2013-02-01

    Samples of BaTiO{sub 3} with different concentrations of Y were synthesized from powders. The mixtures of powders were pressed and sintered at 1500 Degree-Sign C for 1 h. Two groups of samples were processed, one satisfying Ba/(Ti+Y)<1 and the other satisfying Ba/(Ti+Y)=1. X-ray diffraction patterns were analyzed by Rietveld refinement and it was concluded that Y{sup 3+} occupies the Ti{sup 4+} lattice sites. The conductivity behavior as a function of Y concentration suggests that the compensation mechanisms are hole and oxygen vacancies. Due to the presence of charge carriers in the material, high values for the dielectric constant and dielectric loss were observed. Analysis of the microstructure showed that the average grain size decreases as the Y concentration is increased.

  16. Composition changes in sputter deposition of Y-Ba-Cu-O films

    International Nuclear Information System (INIS)

    Hoshi, Y.; Naoe, M.

    1989-01-01

    The authors discuss the mechanism of the composition change in sputter deposition of Y-BA-Cu-O film from YBa 2 Cu 3 O 7-chi target investigated by means of a rf planar magnetron sputtering apparatus. Film composition changes significantly with not only substrate temperature Ts and sputtering gas pressure, but also substrate position. Lack of Cu and Ba content is significant in the film deposited at the substrate position just above the erosion area of the sputtering target. Suppression of bombardment of the substrate surface by negative ions emitted from the target and substrate is effective in increasing Cu and Ba content in the film. These results indicate not only that the sticking probability of the sputtered particles changes with Ts and incident particle energy, but also that high energy particle bombardment of the substrate surface plays an important role in the change of the film composition

  17. Growth and characterizations of Ba2Ti2Fe2As4O single crystals

    Directory of Open Access Journals (Sweden)

    Yun-Lei Sun, Abduweli Ablimit, Jin-Ke Bao, Hao Jiang, Jie Zhou and Guang-Han Cao

    2013-01-01

    Full Text Available Single crystals of a new iron-based superconductor Ba2Ti2Fe2As4O have been grown successfully via a Ba2As3-flux method in a sealed evacuated quartz tube. Bulk superconductivity with Tc ~ 21.5 K was demonstrated in resistivity and magnetic susceptibility measurements after the as-grown crystals were annealed at 500 °C in vacuum for a week. X-ray diffraction patterns confirm that the annealed and the as-grown crystals possess the identical crystallographic structure of Ba2Ti2Fe2As4O. Energy-dispersive x-ray spectra indicate that partial Ti/Fe substitution exists in the [Fe2As2] layers and the annealing process redistributes the Ti within the Fe-plane. The ordered Fe-plane stabilized by annealing exhibits superconductivity with magnetic vortex pinned by Ti.

  18. Pulsed laser deposition of Tl-Ca-Ba-Cu-O films

    International Nuclear Information System (INIS)

    Ianno, N.J.; Liou, S.H.; Woollam, J.A.; Thompson, D.; Johs, B.

    1990-01-01

    Pulsed laser deposition is a technique commonly used to deposit high quality thin films of high temperature superconductors. This paper discusses the results obtained when this technique is applied to the deposition of Tl-Ca-Ba-Cu-O thin films using a frequency doubled Nd:YAG laser operating at 532 nm and an excimer laser operating at 248 nm. Films with onset temperatures of 125 K and zero resistance temperatures of 110 K deposited on (100) oriented MgO from a composite Tl2Ca2Ba2Cu3Ox target were obtained at both wavelengths upon appropriate post deposition annealing. Films deposited at 532 nm exhibit a rough surface, while those deposited at 248 nm are smooth and homogeneous. Upon annealing, films deposited at both wavelengths are single phase Tl2Ca2Ba2Cu3Ox. 12 refs

  19. Thermoelectric properties of conducting polyaniline/BaTiO3 nanoparticle composite films

    Science.gov (United States)

    Anno, H.; Yamaguchi, K.; Nakabayashi, T.; Kurokawa, H.; Akagi, F.; Hojo, M.; Toshima, N.

    2011-05-01

    Conducting polyaniline (PANI)/BaTiO3 nanoparticle composite films with different molar ratio values R=1, 5, 10, and 100 have been prepared on a quartz substrate by casting the m-cresol solution of PANI, (±)-10-camphorsulfonic acid (CSA) and BaTiO3 nanoparticle with an average diameter of about 20 nm. The CSA-doped PANI/BaTiO3 composite films were characterized by x-ray diffraction, Fourier transform infrared spectroscopy, and UV-Vis transmission spectroscopy. The Seebeck coefficient and the electrical conductivity of the films with different R values, together with CSA-doped PANI films, were measured in the temperature range from room temperature to ~400 K. The relation between the Seebeck coefficient and the electrical conductivity in the composite films are discussed from a comparison of them with those of CSA-doped PANI films and other PANI composite films.

  20. Lattice distortion under an electric field in BaTiO3 piezoelectric single crystal

    International Nuclear Information System (INIS)

    Tazaki, Ryoko; Fu Desheng; Daimon, Masahiro; Koshihara, Shin-ya; Itoh, Mitsuru

    2009-01-01

    Lattice distortions under an electric field in a mono-domain of BaTiO 3 ferroelectric crystal have been detected with synchrotron x-ray radiation. The variation of the lattice constant with an electric field observed with high angle diffraction shows a linear response nature of the piezoelectric effect. When an electric field is applied along the spontaneous polarization direction, the c-axis of the lattice elongates and the a-axis of the lattice shrinks at a rate of d 33 = 149 ± 54 pm V -1 and d 31 = -82 ± 61 pm V -1 ; these represent the longitudinal and transverse piezoelectric coefficients of BaTiO 3 crystal, respectively. These results give an insight into the intrinsic piezoelectric response on the lattice scale in BaTiO 3 that has been widely used to explore high performance lead-free piezoelectric alloys.

  1. AEMnSb2 (AE=Sr, Ba): a new class of Dirac materials

    International Nuclear Information System (INIS)

    Farhan, M Arshad; Lee, Geunsik; Shim, Ji Hoon

    2014-01-01

    The Dirac fermions of Sb square net in AEMnSb 2 (AE=Sr, Ba) are investigated by using first-principles calculation. BaMnSb 2 contains Sb square net layers with a coincident stacking of Ba atoms, exhibiting Dirac fermion behavior. On the other hand, SrMnSb 2 has a staggered stacking of Sr atoms with distorted zig-zag chains of Sb atoms. Application of hydrostatic pressure on the latter induces a structural change from a staggered to a coincident arrangement of AE ions accompanying a transition from insulator to a metal containing Dirac fermions. The structural investigations show that the stacking type of cation and orthorhombic distortion of Sb layers are the main factors to decide the crystal symmetry of the material. We propose that the Dirac fermions can be obtained by controlling the size of cation and the volume of AEMnSb 2 compounds. (fast track communication)

  2. Effects of Ba doping on physical properties of La-Ca-Mn-O thin films

    CERN Document Server

    Hong, N H; Sakai, J; Iwasaki, H

    2003-01-01

    Transport and magnetic properties of La-Ba-Ca-Mn-O thin films fabricated by the pulsed laser deposition technique had been investigated systematically to see the effects of substitution of the small atom Ca by Ba which is much bigger. The induced insulator-to-metal (IM) transition was obtained not only in compositions near 0.5 and 0.18 which are boundaries between metallic and insulating phases but also in the heavily doped region. In the region of x > 0.5, the Ba doping causes an anomalous response of the system to the magnetic field and a positive magnetoresistance was observed. Besides, our results concerning the vicinity of 0.5 imply the existence of phase separation. As for x < 0.5, the doping enhances remarkably the paramagnetism-ferromagnetism transition and the IM transition temperatures.

  3. Dosimetry of ultraviolet radiation with BaHfO_3 powders

    International Nuclear Information System (INIS)

    Barrera A, A. A.; Aguilar D, G. A.; Guzman M, J.; Rivera M, T.; Ceron R, V.

    2016-10-01

    Ceramic materials based on pure barium hafnate (BaHfO_3) have been obtained as a powder by the co-precipitation method. The powders obtained have a cubic structure that favors the thermoluminescent and optical properties, through which a better detection of the non-ionizing radiation is allowed. With these powders various tests were performed in the ultraviolet range at different exposure times. These thermoluminescent (Tl) studies were carried out using a Tl 3500 hand held reader which yielded a brightness curve that ranged from room temperature to the 350 degrees Celsius. This BaHfO_3 response exhibits a broad brightness curve with a single peak centered around 225 degrees Celsius. Finally, is reported that there are materials of barium hafnate (BaHfO_3) doped with some rare earths (Eu, Tb) which, instead of improving the performance of the powders, decrease it, so that the use of intrinsic barium hafnate is the most appropriate. (Author)

  4. Software data acquisition system for the ''Chateau de Cristal'' multicounter 74 BaF2

    International Nuclear Information System (INIS)

    Adzama, G.

    1985-01-01

    The ''Chateau de Cristal'' is a 74 BaF2 detector assembly. Other detectors such as Ge (up to 12) and particle detectors can be added to this multidetector. The data acquisition system hardware and software are implemented in 3 VME crates. The operating system is handled by 68000 Motorola microprocessors. This work is dedicated to the initialization and control tasks of the multidetector. Handling of high voltage power supply for the 74 BaF2 detectors via a RS 232 C serial port, CAMAC initialization for the ADC 4300 Lecroy and DFC modules, data exchange between the 3 VME crates and automatic energy calibration for the BaF2 detectors. All the software is written in 68000 Motorola assembly language [fr

  5. Ab Initio Calculations for the BaTiO3 (001) Surface Structure

    Institute of Scientific and Technical Information of China (English)

    XUE Xu-Yan; WANG Chun-Lei; ZHONG Wei-Lie

    2004-01-01

    @@ The ab initio method within the local density approximation is applied to calculate cubic BaTiO3 (001) surface relaxation and rumpling for two different terminations (BaO and TiO2). Our calculations demonstrate that cubic perovskite BaTiO3 crystals possess surface polarization, accompanied by the presence of the relevant electric field.We analyse their electronic structures (band structure, density of states and the electronic density redistribution with emphasis on the covalency effects). The results are also compared with that of the previous ab initio calculations. Considerable increases of Ti-O chemical bond covalency nearby the surface have been observed.The band gap reduces especially for the TiO2 termination.

  6. Simulation of iron impurity in BaTiO{sub 3} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Stashans, Arvids, E-mail: arvids@utpl.edu.e [Grupo de Fisicoquimica de Materiales, Instituto de Quimica Aplicada, Universidad Tecnica Particular de Loja, Apartado 11-01-608, Loja (Ecuador); Castillo, Darwin [Grupo de Fisicoquimica de Materiales, Instituto de Quimica Aplicada, Universidad Tecnica Particular de Loja, Apartado 11-01-608, Loja (Ecuador); Escuela de Electronica y Telecomunicaciones, Universidad Tecnica Particular de Loja, Apartado 11-01-608, Loja (Ecuador)

    2009-05-01

    Iron-doped barium titanate (BaTiO{sub 3}) has been simulated taking into account cubic and tetragonal crystallographic lattices of the crystal. A quantum-chemical method based on the Hartree-Fock formalism has been used throughout the study. The calculated equilibrium structures of Fe-doped crystals reveal the defect-inward displacements of the Ti and O atoms whereas the shifts for the Ba atoms are encountered to be away with respect to the Fe impurity. According to the analysis of electron density population and electron band structure it is found that some unusual chemical bonding might take place between the Fe atom and its six adjacent O atoms. The role of Fe impurity in the ferroelectric polarization of the tetragonal BaTiO{sub 3} crystal has been discussed too.

  7. Simulation of iron impurity in BaTiO3 crystals

    International Nuclear Information System (INIS)

    Stashans, Arvids; Castillo, Darwin

    2009-01-01

    Iron-doped barium titanate (BaTiO 3 ) has been simulated taking into account cubic and tetragonal crystallographic lattices of the crystal. A quantum-chemical method based on the Hartree-Fock formalism has been used throughout the study. The calculated equilibrium structures of Fe-doped crystals reveal the defect-inward displacements of the Ti and O atoms whereas the shifts for the Ba atoms are encountered to be away with respect to the Fe impurity. According to the analysis of electron density population and electron band structure it is found that some unusual chemical bonding might take place between the Fe atom and its six adjacent O atoms. The role of Fe impurity in the ferroelectric polarization of the tetragonal BaTiO 3 crystal has been discussed too.

  8. Study of radiation damage in BaTiO3, using Molecular-dynamics simulations

    International Nuclear Information System (INIS)

    Gonzalez, E.; Abreu, Y.; Cruz, C. M.; Pinnera, I.; Leyva, A.

    2015-01-01

    Molecular-dynamics (MD) simulations were used to calculate atomic displacement probability curves along main crystallographic directions in BaTiO 3 perovskite. A primary knock-on atom (PKA) with a energy range between 10 to 300 eV in principal crystallographic directions at 300 K was introduced. For each sublattice, the simulation was repeated from different initial conditions to estimate the variation in the defect formation process. The formation of Frenkel pairs vary considerably with crystallographic direction and sublattice. Major quantity oxygen defects were found for all the simulated crystallographic directions. Threshold displacement energies are calculated for each atomic specie in the BaTiO 3 material. Also simulations with SRIM code, modeling + Mn implantation in a BaTiO 3 target, at 250 keV were made. (Author)

  9. A General Reliability Model for Ni-BaTiO3-Based Multilayer Ceramic Capacitors

    Science.gov (United States)

    Liu, Donhang

    2014-01-01

    The evaluation of multilayer ceramic capacitors (MLCCs) with Ni electrode and BaTiO3 dielectric material for potential space project applications requires an in-depth understanding of their reliability. A general reliability model for Ni-BaTiO3 MLCC is developed and discussed. The model consists of three parts: a statistical distribution; an acceleration function that describes how a capacitor's reliability life responds to the external stresses, and an empirical function that defines contribution of the structural and constructional characteristics of a multilayer capacitor device, such as the number of dielectric layers N, dielectric thickness d, average grain size, and capacitor chip size A. Application examples are also discussed based on the proposed reliability model for Ni-BaTiO3 MLCCs.

  10. Synthesis and Dielectric Properties of Ba3NaBiNb10O30 Ceramics

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A new niobate Ba3NaBiNb10O30 was synthesized by the solid state reaction.The reaction mixture was characterized by thermogravimetric and differential thermal analysis (TG-DTA),X-ray diffraction and dielectric constant measurements.The results show that Ba3NaBiNb10O30 has an orthorhombic tungsten bronze structure with space group Cmm2 and the unit cell parameters are a=1.7660(1) nm,a=1.7626(1) nm,c=0.78621(6) nm,Z=4.Ba3NaBiNb10O30 undergoes two phase transitions at 200℃ and 400℃,respectively.

  11. High-mobility BaSnO{sub 3} grown by oxide molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Raghavan, Santosh; Schumann, Timo; Kim, Honggyu; Zhang, Jack Y.; Cain, Tyler A.; Stemmer, Susanne, E-mail: stemmer@mrl.ucsb.edu [Materials Department, University of California, Santa Barbara, California 93106-5050 (United States)

    2016-01-01

    High-mobility perovskite BaSnO{sub 3} films are of significant interest as new wide bandgap semiconductors for power electronics, transparent conductors, and as high mobility channels for epitaxial integration with functional perovskites. Despite promising results for single crystals, high-mobility BaSnO{sub 3} films have been challenging to grow. Here, we demonstrate a modified oxide molecular beam epitaxy (MBE) approach, which supplies pre-oxidized SnO{sub x}. This technique addresses issues in the MBE of ternary stannates related to volatile SnO formation and enables growth of epitaxial, stoichiometric BaSnO{sub 3}. We demonstrate room temperature electron mobilities of 150 cm{sup 2} V{sup −1} s{sup −1} in films grown on PrScO{sub 3}. The results open up a wide range of opportunities for future electronic devices.

  12. BaTiO3-based piezoelectrics: Fundamentals, current status, and perspectives

    Science.gov (United States)

    Acosta, M.; Novak, N.; Rojas, V.; Patel, S.; Vaish, R.; Koruza, J.; Rossetti, G. A.; Rödel, J.

    2017-12-01

    We present a critical review that encompasses the fundamentals and state-of-the-art knowledge of barium titanate-based piezoelectrics. First, the essential crystallography, thermodynamic relations, and concepts necessary to understand piezoelectricity and ferroelectricity in barium titanate are discussed. Strategies to optimize piezoelectric properties through microstructure control and chemical modification are also introduced. Thereafter, we systematically review the synthesis, microstructure, and phase diagrams of barium titanate-based piezoelectrics and provide a detailed compilation of their functional and mechanical properties. The most salient materials treated include the (Ba,Ca)(Zr,Ti)O3, (Ba,Ca)(Sn,Ti)O3, and (Ba,Ca)(Hf,Ti)O3 solid solution systems. The technological relevance of barium titanate-based piezoelectrics is also discussed and some potential market indicators are outlined. Finally, perspectives on productive lines of future research and promising areas for the applications of these materials are presented.

  13. Final Report: BaBar Detector and Experimental at SLAC, September 30, 1998 - September 29, 1999

    International Nuclear Information System (INIS)

    Judd, Dennis J.

    2000-01-01

    The Prairie View AandM University High Energy Physics Group with its contingent of three undergraduates physics majors, joined the BaBar Collaboration at SLAC in September 1994. BaBar is the experiment and detector running in the PEP-II ring at SLAC as part of the Asymmetric B Factory project there to study CP violation and heavy flavor physics. The focus of our effort before this year was with the Muon/Neutral Hadron Detector/Instrumented Flux Return (IFD) subgroup within the BaBar collaboration, and particularly with the GEANT simulation of the IFR-. With the GEANT3 simulation essentially FR-ozen, and the GEANT4 full simulation of the IFR- done, we have decided to redirect our efforts toward other areas

  14. Limited Streamer Tubes for the BaBar Instrumented Flux Return Upgrade

    International Nuclear Information System (INIS)

    Lu, C.

    2005-01-01

    Starting from the very beginning of their operation the efficiency of the RPC chambers in the BaBar Instrumented Flux Return (IFR) has suffered serious degradation. After intensive investigation, various remediation efforts had been carried out, but without success. As a result the BaBar collaboration decided to replace the dying barrel RPC chambers about two years ago. To study the feasibility of using the Limited Streamer Tube (LST) as the replacement of RPC we carried out an R and D program that has resulted in BaBar's deciding to replace the barrel RPC's with LST's. In this report we summarize the major detector R and D results, and leave other issues of the IFR system upgrade to the future publications

  15. Final Report BaBar Detector and Experimental at SLAC, September 30, 1998 - September 29, 1999

    CERN Document Server

    Judd, D J

    2000-01-01

    The Prairie View AandM University High Energy Physics Group with its contingent of three undergraduates physics majors, joined the BaBar Collaboration at SLAC in September 1994. BaBar is the experiment and detector running in the PEP-II ring at SLAC as part of the Asymmetric B Factory project there to study CP violation and heavy flavor physics. The focus of our effort before this year was with the Muon/Neutral Hadron Detector/Instrumented Flux Return (IFD) subgroup within the BaBar collaboration, and particularly with the GEANT simulation of the IFR-. With the GEANT3 simulation essentially FR-ozen, and the GEANT4 full simulation of the IFR- done, we have decided to redirect our efforts toward other areas.

  16. Structural study, photoluminescence, and photocatalytic activity of semiconducting BaZrO{sub 3}:Bi nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Borja-Urby, R. [Grupo de Espectroscopia de Materiales Avanzados y Nanoestructurados (EMANA), Centro de Investigaciones en Optica A.C., Leon, Gto 37150 (Mexico); Diaz-Torres, L.A., E-mail: ditlacio@cio.mx [Grupo de Espectroscopia de Materiales Avanzados y Nanoestructurados (EMANA), Centro de Investigaciones en Optica A.C., Leon, Gto 37150 (Mexico); Salas, P. [Centro de Fisica Aplicada y Tecnologia Avanzada, Universidad Nacional Autonoma de Mexico, A.P. 1-1010, Queretaro 76000 (Mexico); Moctezuma, E. [Facultad de Ciencias Quimicas, Universidad Autonoma de San Luis Potosi, Av. Manuel Nava 6, San Luis Potosi, S.L.P., Mexico 78290 (Mexico); Vega, M. [Centro de Geociencias-UNAM, A.P. 1-1010, Queretaro 76000 (Mexico); Angeles-Chavez, C. [Instituto Mexicano del Petroleo, Ciudad de Mexico, D.F. 07730 (Mexico)

    2011-10-25

    Wide band gap nanocrystalline bismuth doped barium zirconate is synthesized by a facile hydrothermal method at 100 deg. C. The obtained cubic perovskites are characterized by powder X-ray diffraction (XRD), UV-VIS diffuse reflectance spectroscopy, photoluminescence (PL) spectroscopy, and photocatalytic activity. The estimated band gap in the 2.4-4.9 eV range, depending on Bi concentration, suggests nanocrystalline BaZrO{sub 3}:Bi as a useful visible-light activated photocatalyst under excitation wavelengths <800 nm. Displacement of main XRD pattern peaks suggest that bismuth ion mostly substitutes into Zr{sup 4+} sites within the BaZrO{sub 3} host lattice. It is found that BaZrO{sub 3}:Bi decomposes methylene blue (MB) under both UV and visible light irradiation. The photocatalyst efficiency depends strongly on Bi content and induced defects.

  17. Growth and scintillation properties of BaMgF{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Yanagida, Takayuki, E-mail: t_yanagi@tagen.tohoku.ac.j [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Kawaguchi, Noriaki [Tokuyama Corporation, Shibuya 3-chome, Shibuya-ku, Tokyo 150-8383 (Japan); Fujimoto, Yutaka; Sugiyama, Makoto; Furuya, Yuki; Kamada, Kei; Yokota, Yuui [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); Yoshikawa, Akira [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan); New Industry Creation Hatchery Center (NICHe), Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Chani, Valery [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

    2010-09-21

    By using the micro-pulling down ({mu}-PD) method, the barium magnesium fluoride (BaMgF{sub 4}) single crystalline scintillator was produced. The crystal was cut and mirror polished to the physical dimensions of 1x2x10 mm{sup 3} for examination of scintillation properties. BaMgF{sub 4} demonstrated {approx}70% transmittance in wavelength range above 170 nm, and strong emission peaking around 205 nm was observed under X-ray excitation. The absolute light yield of BaMgF{sub 4} was 1300{+-}100 ph/MeV, and the decay time profile showed two components as 0.57{+-}0.01 (70%) and 2.2{+-}0.31 (30%) ns at room temperature.

  18. Beyer's non-linearity parameter (B/A) in benzylidene aniline Schiff base liquid crystalline systems

    International Nuclear Information System (INIS)

    Nagi Reddy, M.V.V.; Pisipati, V.G.K.M.; Madhavi Latha, D.; Datta Prasad, P.V.

    2011-01-01

    The non-linearity parameter B/A is estimated for a number of liquid crystal materials of the type N-(p-n-alkoxy benzylidene)-p-n-alkyl anilines, popularly known as nO.m, where n and m are the aliphatic chains on either side of the rigid core, which can be varied from 1 to 18 to realize a number of LC materials with a variety LC phase variants. The B/A values are computed from both density and sound velocity data following standard relations reported in literature. This systematic study in a homologous series provides an opportunity to study how this parameter behaves with (1) either the alkoxy and/or alkyl chain number, (2) with the total chain number (n+m), (3) with increase in molecular weight and (4) whether the linear relations reported in literature either with αT [thermal expansion coefficient (α) and temperature (T)] and sound velocity (u) will hold good or not and if so to what extent. The results are discussed with the body of data available in literature on liquids, liquid mixtures and other LC materials. -- Research highlights: → The Bayer's non-linearity parameter (B/A) is estimated for the first time for a number liquid crystal materials of the type N-(p-n-alkoxy benzylidene)-p-nalkyl anilines. → The magnitude of B/A estimated from sound velocity data is higher compared to that estimated thermal expansion data. → The B/A value decreases with increase in molecular weight with an even odd fashion and reaches a minimum value and saturates. → These studies reveal that both the thermal expansion coefficient and sound velocity are the tools to estimate the non-linear parameter B/A in the case of liquid crystals.

  19. Deficit in complex sequence processing after a virtual lesion of left BA45.

    Directory of Open Access Journals (Sweden)

    Emeline Clerget

    Full Text Available Although the contribution of Broca's area to motor cognition is generally accepted, its exact role remains controversial. A previous functional imaging study has suggested that Broca's area implements hierarchically organised motor behaviours and, in particular, that its anterior (Brodmann area 45, BA45 and posterior (BA44 parts process, respectively, higher and lower-level hierarchical elements. This function of Broca's area could generalize to other cognitive functions, including language. However, because of the correlative nature of functional imaging data, the causal relationship between Broca's region activation and its behavioural significance cannot be ascertained. To circumvent this limitation, we used on-line repetitive transcranial magnetic stimulation to disrupt neuronal processing in left BA45, left BA44 or left dorsal premotor cortex, three areas that have been shown to exhibit a phasic activation when participants performed hierarchically organised motor behaviours. The experiment was conducted in healthy volunteers performing the same two key-press sequences as those used in a previous imaging study, and which differed in terms of hierarchical organisation. The performance of the lower-order hierarchical task (Experiment #1 was unaffected by magnetic stimulation. In contrast, in the higher-order hierarchical task (Experiment #2, "superordinate" task, we found that a virtual lesion of the anterior part of Broca's area (left BA45 delayed the processing of the cue initiating the sequence in an effector-independent way. Interestingly, in this task, the initiation cue only informed the subjects about the rules to be applied to produce the appropriate response but did not allow them to anticipate the entire motor sequence. A second important finding was a RT decrease following left PMd virtual lesions in the superordinate task, a result compatible with the view that PMd plays a critical role in impulse control. The present study

  20. Metal-insulator transition and magnetic properties of La - (Ba/Ca) - Mn - O compounds

    International Nuclear Information System (INIS)

    Anbarasu, V.; Manigandan, A.; Sathiyakumar, S.; Jayabalan, K.; Kaliyaperumal, L.K.

    2009-01-01

    The manganite compounds La 2 BaMn (3+x) P y (where x = 0, 0.5 and 1) and La 2 CaMn 3 O y have been prepared for the importance in the field of magneto resistance materials through solid-state reaction technique. From the Powder XRD patterns it was confirmed that both compounds were in single phase and the refined crystal system matches with superconducting perovskite structure and the lattice parameters were calculated as a = 3.892( 6) A, b = 3.899(3) A and c = 11.619(8) A for La 2 BaMn 3 O y ; a = 3.851(3) A, b = 3.891(9) A and c = 11.542(7) A for La 2 CaMn 3 O y . The low temperature resistivity measurement reveals that the compound La 2 BaMn 3 O y exhibiting M - I transition and the transition temperature was found to be 270 K. The study on magnetization nature of the La 2 BaMn 3+x Oy (where x = 0, 0.5 and I) compounds through vibrating sample magnetometer confirms the superparamagnetic nature at room temperature condition where as La 2 CaMn 3 O y exhibits paramagnetic nature. The structural relations between the prepared manganite systems La 2 BaMn 3 O y and La 2 CaMn 3 O y with superconducting perovskite compound LaBa 2 Cu 3 O 7-y was studied with the technological application of magneto resistive property of the prepared compounds. (author)

  1. Factors influencing formation of highly dispersed BaTiO3 nanospheres with uniform sizes in static hydrothermal synthesis

    International Nuclear Information System (INIS)

    Gao, Jiabing; Shi, Haiyue; Dong, Huina; Zhang, Rui; Chen, Deliang

    2015-01-01

    Highly dispersed BaTiO 3 nanospheres with uniform sizes have important applications in micro/nanoscale functional devices. To achieve well-dispersed spherical BaTiO 3 nanocrystals, we carried out as reported in this paper the systematic investigation on the factors that influence the formation of BaTiO 3 nanospheres by the static hydrothermal process, including the NaOH concentrations [NaOH], molar Ba/Ti ratios (R Ba/Ti ), hydrothermal temperatures, and durations, with an emphasis on understanding the related mechanisms. Barium nitrate and TiO 2 sols derived from tetrabutyl titanate were used as the starting materials. The as-synthesized BaTiO 3 samples were characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, thermogravimetry, differential thermal analysis, and FT-IR spectra. The highly dispersed BaTiO 3 nanospheres (76 ± 13 nm) were achieved under the optimum hydrothermal conditions at 200 °C for 10 h: [NaOH] = 2.0 mol L −1 and R Ba/Ti  = 1.5. Higher NaOH concentrations, higher Ba/Ti ratios, higher hydrothermal temperatures, and longer hydrothermal durations are favorable in forming BaTiO 3 nanospheres with larger fractions of tetragonal phase and higher yields; but too long hydrothermal durations resulted in abnormal growth and reduced the uniformity in particle sizes. The possible formation mechanisms for BaTiO 3 nanocrystals under the static hydrothermal conditions were investigated

  2. Improvement of the performance of microwave X band absorbers based on pure and doped Ba-hexaferrite

    Energy Technology Data Exchange (ETDEWEB)

    Seyyed Afghahi, Seyyed Salman [Department of Materials Science and Engineering, Imam Hossein University, Tehran (Iran, Islamic Republic of); Jafarian, Mojtaba, E-mail: m.jafarian@srbiau.ac.ir [Young Researchers and Elite Club, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Salehi, Mohsen [Young Researchers and Elite Club, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Atassi, Yomen [Department of Applied Physics, Higher Institute for Applied Sciences and Technology, Damascus (Syrian Arab Republic)

    2017-01-01

    Optimum Fe/Ba mole ratio is determined in doped Ba-hexaferrite prepared via mechanical activation. X-ray diffractometer (XRD), scanning electron microscope (SEM), vibrating sample magnetometer (VSM) and vector network analyzer are used to analyze phases, structures, electromagnetic and microwave absorption properties. The mole ratio of Fe/Ba=10 is detected to be optimum for doping and synthesizing the Ba-hexaferrite. In order to achieve high absorption in X band the ions of Zr{sup 4+}–Sn{sup 4+}–Ti{sup 4+}–M{sup 2+} (M=Mg{sup 2+}, Zn{sup 2+}, Cu{sup 2+}, Co{sup 2+}) are used as dopants. The results indicate the formation of single phase Ba-hexaferrite in either pure or doped compounds without any non-magnetic intermediate phases and with spherical and hexagonal morphologies respectively for the pure and doped ferrite. It is found out that BaCo{sub 2}Zr(SnTi){sub 0.5}Fe{sub 8}O{sub 19} compound has the maximum saturation magnetization (49.80 emu/g). Also the composite of BaCo{sub 2}Zr(SnTi){sub 0.5}Fe{sub 8}O{sub 19} 50 wt% in epoxy resin exhibits a minimum reflection loss of −29 dB at 12.2 GHz with 2.6 GHz bandwidth. - Highlights: • Optimum Fe/Ba mole ratio is determined in doped Ba-hexaferrite. • Formation of a single phase M-hexaferrite, pure or doped when Fe/Ba=10. • Preparation of microwave absorber of BaCo{sub 2}Zr(SnTi){sub 0.5}Fe{sub 8}O{sub 19}/epoxy resin, 50 wt%. • The absorber exhibits a minimum RL of −29 dB at 12.2 GHz with 2.6 GHz bandwidth.

  3. Using coral Ba/Ca records to investigate seasonal to decadal scale biogeochemical cycling in the surface and intermediate ocean.

    Science.gov (United States)

    LaVigne, M.; Cobb, K. M.; DeLong, K. L.; Freiberger, M. M.; Grottoli, A. G.; Hill, T. M.; Miller, H. R.; Nurhati, I. S.; Richey, J. N.; Serrato Marks, G.; Sherrell, R. M.

    2016-12-01

    Dissolved barium (BaSW), a bio-intermediate element, is linked to several biogeochemical processes such as the cycling and export of nutrients, organic carbon (Corg), and barite in surface and intermediate oceans. Dynamic BaSW cycling has been demonstrated in the water column on short timescales (days-weeks) while sedimentary records have documented geologic-scale changes in barite preservation driven by export production. Our understanding of how seasonal-decadal scale climate variability impacts these biogeochemical processes currently lacks robust records. Ba/Ca calibrations in surface and deep sea corals suggest barium is incorporated via cationic substitution in both aragonite and calcite. Here we demonstrate the utility of Ba/Ca for reconstructing biogeochemical variability using examples of surface and deep sea coral records. Century-long deep sea coral records from the California Current System (bamboo corals: 900-1500m) record interannual variations in Ba/Ca, likely reflecting changes in barite formation via bacterial Corg respiration or barite saturation state. A surface Porites coral Ba/Ca record from Christmas Island (central equatorial Pacific: 1978-1995) shows maxima during low productivity El Niño warm periods, suggesting that variations in BaSW are driven by biological removal via direct cellular uptake or indirectly via barite precipitation with the decomposition of large phytoplankton blooms at this location. Similarly, a sixteen-year long Siderastera siderea surface coral record from Dry Tortugas, FL (Gulf of Mexico: 1991-2007) shows seasonal Ba/Ca cycles that align with annual chlorophyll and δ13C. Taken together, these records demonstrate the linkages among Corg, nutrient cycling and BaSW in the surface and intermediate ocean on seasonal to decadal timescales. Multi-proxy paleoceanographic reconstructions including Ba/Ca have the potential to elucidate the mechanisms linking past climate, productivity, nutrients, and BaSW cycling in the past.

  4. Particle morphology as a control of permeation in polymer films obtained from MMA/nBA colloidal dispersions.

    Science.gov (United States)

    Lestage, David J; Urban, Marek W

    2004-07-20

    The combination of precision-controlled weight loss measurements and spectroscopic surface FT-IR analysis allowed us to identify unique behaviors of poly(methyl methacrylate) (p-MMA). When MMA and n-butyl acrylate (nBA) are polymerized into p-MMA and p-nBA homopolymer blends, MMA/nBA random copolymers, and p-MMA/p-nBA core-shell morphologies, a controlled mobility and stratification of low molecular weight components occurs in films formed from coalesced colloidal dispersions. Due to different affinities toward water, p-MMA and p-nBA are capable of releasing water at different rates, depending upon particle morphological features of initial dispersions. As coalescence progresses, water molecules are released from the high free volume p-nBA particles, whereas p-MMA retains water molecules for the longest time due to its hydrophilic nature. As a result, water losses at extended coalescence times are relatively small for p-MMA. MMA/nBA copolymer and p-MMA/p-nBA blends follow the same trends, although the magnitudes of changes are not as pronounced. The p-MMA/p-nBA core-shell behavior resembles that of p-nBA homopolymer, which is attributed to significantly lower content of the p-MMA component in particles. Annealing of coalesced colloidal films at elevated temperatures causes migration of SDOSS to the F-A interface, but for films containing primarily p-nBA, reverse diffusion back into the bulk is observed. These studies illustrate that the combination of different particle morphologies and temperatures leads to controllable permeation processes through polymeric films. Copyright 2004 American Chemical Society

  5. Dielectric enhancement of BaTiO3/SrTiO3 superlattices with embedded Ni nanocrystals

    International Nuclear Information System (INIS)

    Xiong Zhengwei; Sun Weiguo; Wang Xuemin; Jiang Fan; Wu Weidong

    2012-01-01

    Highlights: ► The BaTiO 3 /SrTiO 3 superlattices with embedded Ni NCs were successfully fabricated by L-MBE. ► The influence with the various concentrations of Ni nanocrystals embedded in BaTiO 3 /SrTiO 3 superlattices was also discussed. ► The BaTiO 3 /SrTiO 3 superlattices with lower concentration of embedded Ni NCs had higher permittivity and dielectric loss compared with the pure BaTiO 3 /SrTiO 3 superlattices. ► The dielectric enhancement of BaTiO 3 /SrTiO 3 superlattices with embedded Ni NCs was proposed to explained by Drude quasi-free-electron theory. - Abstract: The self-organized Ni nanocrystals (NCs) were embedded in BaTiO 3 /SrTiO 3 superlattices using laser molecular beam epitaxy (L-MBE). The stress of the composite films was increased with the increasing concentration of embedded Ni NCs, as investigation in stress calculation. The influence with the various concentrations of Ni NCs embedded in BaTiO 3 /SrTiO 3 superlattices was also discussed. The internal stress of the films was too strong to epitaxial growth of BaTiO 3 /SrTiO 3 superlattices. Compared with the pure BaTiO 3 /SrTiO 3 superlattices, the BaTiO 3 /SrTiO 3 superlattices with lower concentration of embedded Ni NCs had higher permittivity and dielectric loss. Furthermore, the dielectric enhancement of BaTiO 3 /SrTiO 3 superlattices with embedded Ni NCs was proposed to explained by Drude quasi-free-electron theory.

  6. Conduction Mechanisms in Multiferroic Multilayer BaTiO3/NiFe2O4/BaTiO3 Memristors

    Science.gov (United States)

    Samardzic, N.; Bajac, B.; Srdic, V. V.; Stojanovic, G. M.

    2017-10-01

    Memristive devices and materials are extensively studied as they offer diverse properties and applications in digital, analog and bio-inspired circuits. In this paper, we present an important class of memristors, multiferroic memristors, which are composed of multiferroic multilayer BaTiO3/NiFe2O4/BaTiO3 thin films, fabricated by a spin-coating deposition technique on platinized Si wafers. This cost-effective device shows symmetric and reproducible current-voltage characteristics for the actuating voltage amplitude of ±10 V. The origin of the conduction mechanism was investigated by measuring the electrical response in different voltage and temperature conditions. The results indicate the existence of two mechanisms: thermionic emission and Fowler-Nordheim tunnelling, which alternate with actuating voltage amplitude and operating temperature.

  7. Molecular glues for manipulating enzymes: trypsin inhibition by benzamidine-conjugated molecular glues† †Electronic supplementary information (ESI) available: Synthesis of TEG–BA, Gluen–BA, mGluen–BA and Gluen–Ph; 1H NMR, 13C NMR, MALDI-TOF MS, electronic absorption, and CD spectra; zeta potential distributions; SLS plots; DLS histograms; and related experimental procedures. See DOI: 10.1039/c5sc00524h Click here for additional data file.

    Science.gov (United States)

    Mogaki, Rina

    2015-01-01

    Water-soluble bioadhesive polymers bearing multiple guanidinium ion (Gu+) pendants at their side-chain termini (Gluen–BA, n = 10 and 29) that were conjugated with benzamidine (BA) as a trypsin inhibitor were developed. The Gluen–BA molecules are supposed to adhere to oxyanionic regions of the trypsin surface, even in buffer, via a multivalent Gu+/oxyanion salt-bridge interaction, such that their BA group properly blocks the substrate-binding site. In fact, Glue10–BA and Glue29–BA exhibited 35- and 200-fold higher affinities for trypsin, respectively, than a BA derivative without the glue moiety (TEG–BA). Most importantly, Glue10–BA inhibited the protease activity of trypsin 13-fold more than TEG–BA. In sharp contrast, mGlue27–BA, which bears 27 Gu+ units along the main chain and has a 5-fold higher affinity than TEG–BA for trypsin, was inferior even to TEG–BA for trypsin inhibition. PMID:28706668

  8. Thermophysical properties of proton conducting perovskite: BaCeO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Shukla, Aarti, E-mail: aarti.phy@gmail.com; Parey, Vanshree; Thakur, Rasna; Shrivastava, Archana; Gaur, N. K. [Department of Physics, Barkatullah University, Bhopal-462026 (India)

    2015-06-24

    We present the thermal properties of the proton conducting orthorhombic BaCeO{sub 3} by the means of a Rigid Ion Model (RIM). We report the cohesive energy (φ), Reststrahlen frequency (υ), Debye temperature (θ{sub D}) and Gruneisen parameter (γ). The value of Gruneisen parameter (γ), which supports the earlier, reported values. Besides, the specific heat values presented in this work by using RIM are in reasonable agreement with the available experimental data for BaCeO{sub 3} at low temperature (2K ≤ T ≤ 300K)

  9. Vigilancia sanitaria de cianobacterias en aguas de consumo humano y aguas de baño

    OpenAIRE

    Guadalupe Martínez Juárez; Idoia Merino Azcue

    2008-01-01

    Las autoridades de Salud Pública tienen implantados y consolidados programas de vigilancia sanitaria de aguas de consumo humano y aguas de baño, cuya finalidad es evitar riesgos para la salud de la población que consume agua o que utiliza con fines recreativos zonas de baño continentales. A la luz de los conocimientos científicos actuales, la proliferación de cianobacterias es un nuevo riesgo, que es necesario tener en cuenta en los programas de protección de la salud. En el presente trabajo,...

  10. Desorption of Ba and 226Ra from river-borne sediments in the Hudson estuary

    International Nuclear Information System (INIS)

    Li, Y.-H.

    1979-01-01

    The pronounced desorption of Ba and 226 Ra from river-borne sediments in the Hudson estuary can be explained quantitatively by the drastic decrease in the distribution coefficients of both elements from a fresh to a salty water medium. The desorption in estuaries can augment, at least, the total global river fluxes of dissolved Ba and 226 Ra by one and nine times, respectively. The desorption flux of 226 Ra from estuaries accounts for 17-43% of the total 226 Ra flux from coastal sediments. Two mass balance models depicting mixing and adsorption-desorption processes in estuaries are discussed. (Auth.)

  11. Parnaíba and San Francisco rivers: traveler's fascination and technicians' rationality

    Directory of Open Access Journals (Sweden)

    Gercinair Silvério Gandara

    2013-02-01

    Full Text Available Considering that the environmental variable opens up the prospect of countless historical approaches, I will give attention (having Parnaíba and San Francisco river as scenery to the travelers' accounts,the reports of technicians and engineers, to the political speeches and governmental decisionsundertaken in order to promote better navigability in both rivers. I will also highlight the studies and services aimed to the removal of obstacles the environment from the Parnaíba and San Franciscorivers in the second half the nineteenth century and first half of the twentieth century.

  12. An overview of the dry storage of nuclear fuels with the BaCo code

    International Nuclear Information System (INIS)

    Marino, A.

    2009-01-01

    The BaCo code was applied to simulate the behaviour for a PHWR fuel under storage conditions showing a strong dependence on the original design of the fuel and the irradiation history. In particular, the results of the statistical analysis of BaCo indicate that the integrity of the fuel are determined by the manufacture tolerances and the solicitations during the NPP irradiation. The main conclusion of the present study is that the fuel temperature of the device should be carefully controlled in order to ensure safe storage conditions. (author)

  13. Compensation mechanisms at high temperature in Y-doped BaTiO3

    International Nuclear Information System (INIS)

    Paredes-Olguín, M.; Lira-Hernández, I.A.; Gómez-Yáñez, C.; Espino-Cortés, F.P.

    2013-01-01

    Samples of BaTiO 3 with different concentrations of Y were synthesized from powders. The mixtures of powders were pressed and sintered at 1500 °C for 1 h. Two groups of samples were processed, one satisfying Ba/(Ti+Y) 3+ occupies the Ti 4+ lattice sites. The conductivity behavior as a function of Y concentration suggests that the compensation mechanisms are hole and oxygen vacancies. Due to the presence of charge carriers in the material, high values for the dielectric constant and dielectric loss were observed. Analysis of the microstructure showed that the average grain size decreases as the Y concentration is increased.

  14. Magnetic levitation and stiffness in melt-textured Y-Ba-Cu-O

    International Nuclear Information System (INIS)

    Hull, J.R.; Mulcahy, T.M.; Salama, K.; Selvamanickam, V.; Weinberger, B.R.; Lynds, L.

    1992-01-01

    Magnetic levitation and stiffness have been measured in several systems composed of a permanent magnet elastically suspended above a stationary melt-textured sample of Y-Ba-Cu-O. The levitation force and vertical stiffness have been calculated on the basis of magnetization measurements of the same system, and the calculated results showed excellent agreement with the experimental measurements. Based on the force and magnetization measurements, it is predicted that the same Y-Ba-Cu-O material configured in a geometry suitable for magnetic bearings could produce a levitation pressure of 100--400 kPa at 20 K

  15. Vigilancia sanitaria de cianobacterias en aguas de consumo humano y aguas de baño

    Directory of Open Access Journals (Sweden)

    Guadalupe Martínez Juárez

    2008-06-01

    Full Text Available Las autoridades de Salud Pública tienen implantados y consolidados programas de vigilancia sanitaria de aguas de consumo humano y aguas de baño, cuya finalidad es evitar riesgos para la salud de la población que consume agua o que utiliza con fines recreativos zonas de baño continentales. A la luz de los conocimientos científicos actuales, la proliferación de cianobacterias es un nuevo riesgo, que es necesario tener en cuenta en los programas de protección de la salud. En el presente trabajo, cuyo principal objetivo es conocer la presencia de cianobacterias y microcistinas en aguas utilizadas para consumo humano y baño, se muestran los resultados obtenidos en los programas de vigilancia llevados a cabo en el Área de Salud de Talavera de la Reina en los últimos cuatro años. Se ha realizado un estudio descriptivo de la presencia de cianobacterias y microcistinas, en agua bruta de la captación de dos embalses y en agua tratada a la salida de dos plantas de tratamiento de agua potable. Esto mismo se ha estudiado en otros dos embalses utilizados para baño en época estival. Para ello se han efectuado muestreos quincenales y posterior identificación y recuento de cianobacterias y determinación de microcistinas disueltas en agua mediante técnica ELISA.De los resultados de la vigilancia de aguas de consumo humano, se concluye que los valores de microcistinas detectados en los embalses no son elevados, apareciendo en menos del 6% de los muestreos efectuados y que el tratamiento aplicado en las plantas de tratamiento de agua potable, es eficaz para su eliminación. De la vigilancia de cianobacterias en el agua de baño, se concluye que a lo largo de tres temporadas, en el 48% de los muestreos realizados en las dos zonas de baño del área, se han superado las 100.000 células/ml, valor guía dado por la OMS, para valorar probabilidad moderada de efectos adversos en bañistas.Destacar que es necesario disponer de datos sobre exposición a

  16. 65Zn and 133Ba standardizing by photon-photon coincidence counting

    Science.gov (United States)

    Loureiro, Jamir S.; da Cruz, Paulo A. L.; Iwahara, Akira; Delgado, José U.; Lopes, Ricardo T.

    2018-03-01

    The LNMRI/Brazil has deployed a system using X-gamma coincidence technique for the standardizing radionuclide, which present simple and complex decay scheme with X-rays of energy below 100 keV. The work was carried on radionuclide metrology laboratory using a sodium iodide detector, for gamma photons, in combination with a high purity germanium detector for X-rays. Samples of 65Zn and 133Ba were standardized and the results for both radionuclides showed good precision and accuracy when compared with reference values. The standardization differences were 0.72 % for 65Zn and 0.48 % for 133Ba samples.

  17. Ferromagnetic Instability in AFe4Sb12 (A = Ca, Sr, and Ba)

    OpenAIRE

    Matsuoka, E.; Hayashi, K.; Ikeda, A.; Tanaka, K.; Takabatake, T.; Higemoto, W.; Matsumura, M.

    2004-01-01

    Magnetic, transport and thermal properties of AFe4Sb12 (A = Ca, Sr, Ba) are reported. All three compounds show a maximum in both the magnetic susceptibility and thermopower at 50 K, and a large electronic specific heat coefficient of 100 mJ/mol K2. These properties are the characteristics of a nearly ferromagnetic metal. Furthermore, a remanent moment of the order of 10-3muB/Fe was observed below 54, 48, and 40 K for A = Ca, Sr, and Ba, respectively. The volume fraction of the ferromagnetic c...

  18. Phase diagrams for systems Cu2S-AIIS (AII=Mg, Ca, Sr, Ba)

    International Nuclear Information System (INIS)

    Andreev, O.V.; Sikerina, N.V.; Solov'eva, A.V.

    2005-01-01

    By the methods of physicochemical analysis phase diagrams of Cu 2 S-A II S (A II =Mg, Ca, Sr, Ba) systems are studied. The system Cu 2 S-SrS is of eutectic type with eutectic coordinates 1095 K and 21.5 mol.% of SrS. Solubility of SrS in Cu 2 S is 2 mol.% at 1095 K. Regularities of phase diagram changes of Cu 2 S-A II S (A II =Mg, Ca, Sr, Ba) system are determined. Thermodynamic analysis is done [ru

  19. Magnetic moment measurement of 140Ba nuclei using transient field technique

    International Nuclear Information System (INIS)

    Saxena, Mansi; Mandal, S.; Siwal, Davinder; Rainovski, G.; Danchev, M.; Damyanova, A.; Gladnishki, K.; Leske, J.; Bauer, C.; Bloch, T.; John, P.; Pietralla, N.; Wollersheim, H.J.; Kojouharov, I.; Pietri, S.; Schaffner, H.

    2011-01-01

    Mixed symmetry states have been identified in the neutron proton version of the Interacting Boson Model. The motivation of this experiment is to identify uniquely one phonon mixed symmetry states in 140 Ba nuclei by g factor measurement of the states. Magnetic moments measurements provide substantial information on the microscopic structure of the nuclei as the magnetic moment of a nuclei is described by the wave function of one state only. In this present paper we report the preliminary results of the g factor measurement of the first 2 + state of 140 Ba

  20. Stoichiometric analysis of Y-Ba-Cu-O superconductors using deuterons

    International Nuclear Information System (INIS)

    Tang, S.M.; Ong, T.H.; Tan, M.G.; Loh, K.K.; Sow, C.H.; Yuan, B.; Orlic, I.

    1993-01-01

    In principle, deuteron irradiation can be used for a complete stoichiometric analysis of Y-Ba-Cu-O superconductors. The contents of all the four chemical constituents can be determined by simultaneous detection of the 0.871 MeV prompt gamma rays from the 16 O(d, pγ) 17 O * reaction and of the characteristic X-rays produced by DIXE (deuteron induced X-ray emission). In this paper we present the approach taken and the results obtained in exploring the applicability of this technique for accurate quantitative determinations of the chemical constituents of bulk Y-Ba-Cu-O superconductors. (orig.)

  1. Ba3NbAs3O: synthesis, crystal structure, Raman spectroscopy and bonding analysis

    International Nuclear Information System (INIS)

    Monconduit, L.; Tillard, M.; Favier, F.; Belin, C.

    1999-01-01

    The crystal structure of Ba 3 NbAs 3 O has been solved by crystal X-ray analysis (CAD-4 automatic diffractometer, Mo Kα radiation). The compound crystallizes in space group Pnma, a=6.724(2), b=11.100(2), c=13.462(3) A, V=1004.7(4) A 3 , Z=4. The structure has been refined to R1=0.0343 for 964 independent reflections, it can be described as packing of nearly tetrahedral NbAs 3 O 6- anions, their coordination by Ba 2+ cations forming interconnected trigonal prisms. The chemical bonding has been analyzed by MO calculations and Raman spectroscopy. (orig.)

  2. Fluorine dynamics in BaF2 superionic conductors investigated by NMR

    OpenAIRE

    Gumann, Patryk

    2008-01-01

    In this work the dynamics of fluorine in solid-state electrolytes having BaF2-structure was investigated using three different NMR-methods: field cycling relaxometry, lineshape analysis, and static field gradient NMR. For this purpose a pure BaF2 crystal, as well as crystals doped with trivalent impurities (LaF3), were studied as a function of temperature. The main goal of this investigation was to utilize the structure information provided by neutron scattering and MAS NMR data in order to s...

  3. Oxygen permeability of perovskite-type BaBi1-xLaxO3-δ

    International Nuclear Information System (INIS)

    Yaremchenko, A.A.; Kharton, V.V.; Viskup, A.P.; Naumovich, E.N.; Samokhval, V.V.

    1998-01-01

    Oxygen permeability, electrical conductivity, and thermal expansion of BaBi 1-x La x O 3-δ (x = 0, 0.2, and 0.4) perovskite-like solid solutions have been found to decrease with lanthanum content. Thermal expansion coefficients of the ceramics are (11.9--12.8) x 10 -6 K -1 . Oxygen transport through the BaBi(La)O 3-δ dense ceramic membranes within the membrane thickness range of 0.6 < d < 1.2 mm has been shown to be limited by both bulk ionic conductivity and surface exchange rate

  4. Ab initio study of double perovskites Ba{sub 2}DySbO{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Jha, Dhiraj Kumar; Mandal, Golak; Singh, B. K. [Department of Physics, T.M. Bhagalpur University, Bhagalpur, Bihar 812007 (India); Ray, Chandan [Department of Applied Physics & Ballistics, F. M. University, Balasore, Odisha, 756019 (India); Himanshu, A. K., E-mail: akh@vecc.gov.in [Nanostructured & Advanced Material Laboratory, Variable Energy Cyclotron Centre, 1/AF, Bidhannagar, Saltlake, Kolkata-700064 (India); Kumar, Uday [Department of Physical Sciences, IISER Kolkata, Mohanpur Campus, Mohanpur, West Bengal (India); Choudhary, B. K. [Department of Physics, Ranchi University, Jharkhand-834001 (India)

    2016-05-23

    First principle study of the electronic band structure of Ba2DySbO{sub 6} synthesied by the solid state reaction technique have been performed within the framework of density function theory using WIEN2K. It has been shown in the absence of electron-electron interaction (U=0), BaDySO{sub 6} behaves like a half-metal. Even in the presence of DFT+U, electron-electron interaction via the Hubbard term (from U = 0, 2.72e -7.02 eV), it still shows half metals.

  5. Ab initio study of double perovskites Ba_2DySbO_6

    International Nuclear Information System (INIS)

    Jha, Dhiraj Kumar; Mandal, Golak; Singh, B. K.; Ray, Chandan; Himanshu, A. K.; Kumar, Uday; Choudhary, B. K.

    2016-01-01

    First principle study of the electronic band structure of Ba2DySbO_6 synthesied by the solid state reaction technique have been performed within the framework of density function theory using WIEN2K. It has been shown in the absence of electron-electron interaction (U=0), BaDySO_6 behaves like a half-metal. Even in the presence of DFT+U, electron-electron interaction via the Hubbard term (from U = 0, 2.72e -7.02 eV), it still shows half metals.

  6. Influence of BaO in perovskite electrodes for the electrochemical reduction of NOx

    DEFF Research Database (Denmark)

    Simonsen, Vibe Louise Ernlund; Johnsen, M.M.; Kammer Hansen, Kent

    2007-01-01

    Using the point electrode method, the effect of BaO on electrochemical reduction of NO (x) was investigated using the perovskites La0.85Sr0.15MnO3 (LSM15) and La0.85Sr0.15CoO3 (LSCo15) as electrode materials. The experiments were carried out in the temperature range 400-600 degrees C in 1% NO and...... favored oxygen reduction compared to reduction of nitric oxide. The LSCO15 electrode containing BaO reacted to form a K2NiF4-structure and was not tested further....

  7. 65Zn and 133Ba standardizing by photon-photon coincidence counting

    International Nuclear Information System (INIS)

    Loureiro, Jamir S.; Cruz, Paulo A.L. da; Iwahara, Akira; Delgado, José U.; Lopes, Ricardo T.

    2017-01-01

    The LNMRI/Brazil has deployed a system using X-gamma coincidence technique for the standardizing radionuclide, which present simple and complex decay scheme with X-rays of energy below 100 keV. The work was carried on radionuclide metrology laboratory using a sodium iodide detector, for gamma photons, in combination with a high purity germanium detector for X-rays. Samples of 65 Zn and 133 Ba were standardized and the results for both radionuclides showed good precision and accuracy when compared with reference values. The standardization differences were 0.72 % for 65 Zn and 0.48 % for 133 Ba samples. (author)

  8. Elastic properties of cubic perovskite BaRuO{sub 3} from first-principles calculations

    Energy Technology Data Exchange (ETDEWEB)

    Han Deming; Liu Xiaojuan; Lv Shuhui; Li Hongping [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Meng Jian, E-mail: jmeng@ciac.jl.c [State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2010-08-01

    We present first-principles investigations on the structural and elastic properties of the cubic perovskite BaRuO{sub 3} using density-functional theory within both local density approximation (LDA) and generalized gradient approximation (GGA). Basic physical properties, such as lattice constant, shear modulus, elastic constants (C{sub ij}) are calculated. The calculated energy band structures show that the cubic perovskite BaRuO{sub 3} is metallic. We have also predicted the Young's modulus (Y), Poisson's ratio ({upsilon}), and Anisotropy factor (A).

  9. Energy Calibration of the BaBar EMC Using the Pi0 Invariant Mass Method

    Energy Technology Data Exchange (ETDEWEB)

    Tanner, David J.; /Manchester U.

    2007-04-06

    The BaBar electromagnetic calorimeter energy calibration method was compared with the local and global peak iteration procedures, of Crystal Barrel and CLEO-II. An investigation was made of the possibility of {Upsilon}(4S) background reduction which could lead to increased statistics over a shorter time interval, for efficient calibration runs. The BaBar software package was used with unreconstructed data to study the energy response of the calorimeter, by utilizing the {pi}{sup 0} mass constraint on pairs of photon clusters.

  10. Investigation of {sup 136} Ba gamma-Transitions in the (n,n` gamma) Reaction

    Energy Technology Data Exchange (ETDEWEB)

    Sergiwa, S M [University of Garyuonis, Benghazi, (Libyan Arab Jamahiriya); Rateb, G M; Zleetni, S M; dufani, M M; Shermit, A M; Al Hamidi, M M [Tajoura Nuclear Research Center, Tripoli, (Libyan Arab Jamahiriya); El-Ahrash, M S [7th of April University, Zawia, (Libyan Arab Jamahiriya)

    1995-10-01

    Using the reactor fast neutron beam, angular distribution and linear polarization of gamma-rays emitted from the {sup 136} Ba (n,n` gamma) reaction were measured. From these measurements, a decay scheme of {sup 1}36{sup B}a has been constructed. New spin and parity (J{pi}) assignments as well as resolving ambiguities in previous assignments for some levels were done. In addition, multipole mixing rations ({delta} - values, important for model comparison) have been unambiguously determined for many gamma-transitions. 1 fig., 2 tabs.

  11. Operational Aspects of Dealing with the Large BaBar Data Set

    Energy Technology Data Exchange (ETDEWEB)

    Trunov, Artem G

    2003-06-13

    To date, the BaBar experiment has stored over 0.7PB of data in an Objectivity/DB database. Approximately half this data-set comprises simulated data of which more than 70% has been produced at more than 20 collaborating institutes outside of SLAC. The operational aspects of managing such a large data set and providing access to the physicists in a timely manner is a challenging and complex problem. We describe the operational aspects of managing such a large distributed data-set as well as importing and exporting data from geographically spread BaBar collaborators. We also describe problems common to dealing with such large datasets.

  12. Syntheses of nanocrystalline BaTiO3 and their optical properties

    Science.gov (United States)

    Yu, J.; Chu, J.; Zhang, M.

    Stoichiometric and titanium-excess nanocrystalline barium titanates were synthesized using a hydrothermal process at various hydrothermal temperatures and with further heat treatment at 500 °C and 900 °C. Owing to the different process conditions, the excess titanium exists in different states and configurations within the nanocrystalline BaTiO3 matrix; this was demonstrated by X-ray diffraction, Raman scattering, and photoluminescence. In these nanocrystalline BaTiO3, the 590, 571, 543 and 694 nm light emission bands were observed; mechanisms leading to such emissions were also discussed.

  13. Defect chemistry of ''BaCuO2''. Pt. 2. Transport properties and nature of defects

    International Nuclear Information System (INIS)

    Chiodelli, G.; Consiglio Nazionale delle Ricerche, Pavia; Anselmi-Tamburini, U.; Consiglio Nazionale delle Ricerche, Pavia; Arimondi, M.; Consiglio Nazionale delle Ricerche, Pavia; Spinolo, G.; Consiglio Nazionale delle Ricerche, Pavia; Flor, G.; Consiglio Nazionale delle Ricerche, Pavia

    1995-01-01

    The charge transport properties of ''BaCuO 2 '' with 88:90 (Ba:Cu) cation ratio were characterized by thermopower, electrical conductivity and ionic transport number measurements in a wide range of temperature and oxygen partial pressure conditions. The nature of carriers is always represented by small polarons due to self-trapping of the electronic holes generated by the oxygen non-stoichiometry equilibrium. Some anomalies in carrier mobility as a function of temperature are shown not to be related to incomplete ionization of oxygen atoms on interstitial sites (orig.)

  14. Emission probability determination of {sup 133}Ba by the sum-peak method

    Energy Technology Data Exchange (ETDEWEB)

    Silva, R.L. da; Almeida, M.C.M. de; Delgado, J.U.; Poledna, R.; Araujo, M.T.F.; Trindade, O.L.; Veras, E.V. de; Santos, A.; Rangel, J.; Ferreira Filho, A.L., E-mail: ronaldo@ird.gov.br, E-mail: marcandida@yahoo.com.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2016-07-01

    The National Laboratory of Metrology Ionizing Radiation (LNMRI/IRD/CNEN) has several measurement methods in order to ensure low uncertainties about the results. Through gamma spectrometry analysis by sum-peak absolute method they were performed the standardization of {sup 133}Ba activity and your emission probability determination of different energies with reduced uncertainties. The advantages of radionuclides calibrations by absolute method are accuracy, low uncertainties and is not necessary the use of radionuclides reference standards. {sup 133}Ba is used in research laboratories on calibration detectors in different work areas. The uncertainties for the activity and for the emission probability results are lower than 1%. (author)

  15. {sup 65}Zn and {sup 133}Ba standardizing by photon-photon coincidence counting

    Energy Technology Data Exchange (ETDEWEB)

    Loureiro, Jamir S.; Cruz, Paulo A.L. da; Iwahara, Akira; Delgado, José U., E-mail: palcruz@ird.gov.br [Instituto de Radioproteção e Dosimetria (LNMRI/IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. Nacional de Metrologia das Radiações Ionizantes; Lopes, Ricardo T. [Coordenacao de Pos-Graduacao e Pesquisa de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear

    2017-07-01

    The LNMRI/Brazil has deployed a system using X-gamma coincidence technique for the standardizing radionuclide, which present simple and complex decay scheme with X-rays of energy below 100 keV. The work was carried on radionuclide metrology laboratory using a sodium iodide detector, for gamma photons, in combination with a high purity germanium detector for X-rays. Samples of {sup 65}Zn and {sup 133}Ba were standardized and the results for both radionuclides showed good precision and accuracy when compared with reference values. The standardization differences were 0.72 % for {sup 65}Zn and 0.48 % for {sup 133}Ba samples. (author)

  16. Redox reactions and mechanism of luminescence in BaFCl:Eu

    CERN Document Server

    Upadeo, S V; Gundurao, T K

    1998-01-01

    The phenomenon of stimulable luminescence of phosphors pre-irradiated with high-energy radiation is widely used in the field of imaging. Phosphors such as BaFX:Eu (X = Cl, Br) are extensively used in x-ray screens for digital image processing. There is, however, divided opinion regarding the mechanism responsible for the luminescence process in these materials. In this paper we have discussed the role of Eu sup 3 sup +reversible Eu sup 2 sup + conversion in BaFCl:Eu phosphor using PL, TL, TL emission and ESR techniques. (author)

  17. Anisotropy and dimensional characteristics in CVD route Y1Ba2Cu3O7-δ

    International Nuclear Information System (INIS)

    Watanabe, K.; Kobayashi, N.; Awaji, S.; Yamane, H.; Hirai, T.; Muto, Y.

    1993-01-01

    The anisotropic behaviors of the upper critical field B c2 and the critical current density J c were investigated in Y 1 Ba 2 Cu 3 O 7-δ films prepared by a chemical vapor deposition (CVD) route. The angular dependence of J c at fixed temperature, the field dependence of J c at fixed angle, and the temperature dependence of J c at fixed field were measured. The obtained results were explored in terms of the dimensional superconducting characteristics. The important information on the anisotropic behaviors of J c in CVD-Y 1 Ba 2 Cu 3 O 7-δ was discussed from a viewpoint of the flux pinning. (orig.)

  18. Sequential structural and antiferromagnetic transitions in BaFe2Se3 under pressure

    Science.gov (United States)

    Zhang, Yang; Lin, Ling-Fang; Zhang, Jun-Jie; Dagotto, Elbio; Dong, Shuai

    2018-01-01

    The discovery of superconductivity in the two-leg ladder compound BaFe2S3 has established the 123-type iron chalcogenides as a novel and interesting subgroup of the iron-based superconductor family. However, in this 123 series, BaFe2Se3 is an exceptional member, with a magnetic order and crystalline structure different from all others. Recently, an exciting experiment reported the emergence of superconductivity in BaFe2Se3 at high pressure [J. Ying et al., Phys. Rev. B 95, 241109(R) (2017), 10.1103/PhysRevB.95.241109]. In this paper, we report a first-principles study of BaFe2Se3 . Our analysis unveils a variety of qualitative differences between BaFe2S3 and BaFe2Se3 , including in the latter an unexpected chain of transitions with increasing pressure. First, by gradually reducing the tilting angle of iron ladders, the crystalline structure smoothly transforms from P n m a to C m c m at ˜6 GPa. Second, the system becomes metallic at 10.4 GPa. Third, its unique ambient-pressure Block antiferromagnetic ground state is replaced by the more common stripe (so-called CX-type) antiferromagnetic order at ˜12 GPa, the same magnetic state as the 123-S ladder. This transition is found at a pressure very similar to the experimental superconducting transition. Finally, all magnetic moments vanish at 30 GPa. This reported theoretical diagram of the complete phase evolution is important because of the technical challenges to capture many physical properties in high-pressure experiments. The information obtained in our calculations suggests different characteristics for superconductivity in BaFe2Se3 and BaFe2S3 : in 123-S pairing occurs when magnetic moments vanish, while in 123-Se the transition region from Block- to CX-type magnetism appears to catalyze superconductivity. Finally, an additional superconducting dome above ˜30 GPa is expected to occur.

  19. The ICNP BaT - from translation tool to translation web service.

    Science.gov (United States)

    Schrader, Ulrich

    2009-01-01

    The ICNP BaT has been developed as a web application to support the collaborative translation of different versions of the ICNP into different languages. A prototype of a web service is described that could reuse the translations in the database of the ICNP BaT to provide automatic translations of nursing content based on the ICNP terminology globally. The translation web service is based on a service-oriented architecture making it easy to interoperate with different applications. Such a global translation server would free individual institutions from the maintenance costs of realizing their own translation services.

  20. Electronic structure of PrBa2Cu3O7

    International Nuclear Information System (INIS)

    Singh, D.J.

    1994-01-01

    Electronic-structure calculations, within the local spin density approximation (LSDA), are reported for PrBa 2 Cu 3 O 7 . Significant charge transfer from the Pr ions to both the CuO 2 planes and the chains is found relative to YBa 2 Cu 3 O 7 . This supports hole depletion explanations for the insulating character of PrBa 2 Cu 3 O 7 . The LSDA electronic structure shows a prominent ''ridge'' Fermi surface analogous to that in YBa 2 Cu 3 O 7 , but broader. It is proposed that high-resolution positron measurements of this width may provide a useful test of hole depletion models

  1. Kulturna baština - poticatelj dječjeg razvoja (likovni aspekt)

    OpenAIRE

    Kuščević, Dubravka

    2015-01-01

    Kulturna baština slika je života određene društvene zajednice, a nastala je kao posljedica mnogih povijesnih previranja te je kao takva predmet proučavanja mnogih znanstvenih disciplina. Bez kulturne uvjetovanosti nije moguće shvatiti povijest i razvoj naroda i društava, a bez kulture, s obzirom da predstavlja temeljnu antropološku komunikaciju, nije moguć ni život pojedinca u zajednici. Mnogi oblici kulturne baštine kriju u sebi različita povijesna značenja koja produbljuju spoznaju stvar...

  2. The Impact of Different Permissible Exposure Limits on Hearing Threshold Levels Beyond 25 dBA

    OpenAIRE

    Sayapathi, Balachandar S; Su, Anselm Ting; Koh, David

    2014-01-01

    Background: Development of noise-induced hearing loss is reliant on a few factors such as frequency, intensity, and duration of noise exposure. The occurrence of this occupational malady has doubled from 120 million to 250 million in a decade. Countries such as Malaysia, India, and the US have adopted 90 dBA as the permissible exposure limit. According to the US Occupational Safety and Health Administration (OSHA), the exposure limit for noise is 90 dBA, while that of the US National Institut...

  3. Nitrogen induced ferromagnetism in Cobalt doped BaTiO3

    Directory of Open Access Journals (Sweden)

    Chandrima Mitra

    2012-09-01

    Full Text Available The electronic structure and magnetism of Cobalt doped BaTiO3 (BaTi1−xCoxO3 is investigated. Substitutional Nitrogen on an Oxygen site is found to play an important role in inducing net magnetic moments in the system. The presence of a Nitrogen atom as nearest neighbour to a Cobalt atom is crucial in producing spin splitting of both the Nitrogen and Cobalt states thereby introducing a net local magnetic moment. The introduction of Nitrogen is further found to enhance ferromagnetic interactions between Cobalt atoms.

  4. Standardization of 137mCs+137mBa by Liquid Scintillation; Calibracion de 137Cs+137mBa por Centelleo Liquido

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, L.; Los Arcos, J.M.; Grau, A.

    1995-07-01

    A procedure for the preparation of a stable, homogeneous solution of 137Cs+''137mBa, for use in liquid scintillation measurements, is described. Its count rate stability and spectral time evolution has been followed for several weeks. The solution has been standardised by the CIEMAT/NIST method in both Ultima-Gold and Insta-Gel, to a combined uncertainty lower than 0,51 % (k=l). (Author) 5 refs.

  5. Ruthenium perovskites of type Ba/sub 2/BRuO/sub 6/ and Ba/sub 3/BRu/sub 2/O/sub 9/ with B = indium, rhodium

    Energy Technology Data Exchange (ETDEWEB)

    Schaller, H U; Kemmler-Sack, S [Tuebingen Univ. (Germany, F.R.). Lehrstuhl fuer Anorganische Chemie 2

    1981-02-01

    The black perovskites Ba/sub 2/InRu/sup 5 +/O/sub 6/ and Ba/sub 3/InRu/sub 2/O/sub 9/ (mean oxydation state of ruthenium: +4.5) adopt the hexagonal BaTiO/sub 3/ structure and form a continuous series of mixed crystals. According to the intensity calculations and analysis of the vibrational spectroscopic data an ordered distribution between indium and ruthenium is present: 1:1 order in Ba/sub 2/RuO/sub 6/ (space group P-3m1 respective Dsub(3d)/sup 3/; R' = 5.3%); 1:2 order in Ba/sub 3/InRu/sub 2/O/sub 9/ (space group P6/sub 3//mmc respective Dsub(6h)/sup 4/; R' = 4.6%). The corresponding black Rh compounds, Ba/sub 2/RhRuO/sub 6/ and Ba/sub 3/RhRu/sub 2/O/sub 9/, crystallize in the rhombohedral 9 L type of BaRuO/sub 3/ (author).

  6. Enhancement of polarization property of silane-modified BaTiO3 nanoparticles and its effect in increasing dielectric property of epoxy/BaTiO3 nanocomposites

    Directory of Open Access Journals (Sweden)

    Thi Tuyet Mai Phan

    2016-03-01

    Full Text Available The surface modification of synthesized nano-BaTiO3 particles was carried out using γ-aminopropyl trimethoxy silane (γ-APS in an ethanol/water solution. The modified particles were characterized by FTIR, TGA, surface charge analysis, and by dielectric constant measurement. The silane molecules were attached to the surface of BaTiO3 particles through SiOBaTiO3 bonds. The γ-APS grafted on BaTiO3 made the dielectric constant of the particles increase at frequencies ≥0.3 kHz in a wide range of temperature (25 °C–140 °C, due to the presence of NH2 groups. The dependence of the polarization vs. electrical field was measured in order to elucidate the dielectric behavior of the silane treated BaTiO3 in comparison to untreated BaTiO3. The nanocomposite based on epoxy resin containing BaTiO3 nanoparticles untreated and treated with γ-APS was also prepared and characterized. The results indicated that the γ-APS-modified BaTiO3 surfaces significantly enhanced the dielectric property of the nanocomposite.

  7. High-pressure densified solid solutions of alkaline earth hexaborides (Ca/Sr, Ca/Ba, Sr/Ba) and their high-temperature thermoelectric properties

    International Nuclear Information System (INIS)

    Gürsoy, M.; Takeda, M.; Albert, B.

    2015-01-01

    Solid solutions of alkaline earth hexaborides were synthesized and densified by spark plasma sintering at 100 MPa. The high-temperature thermoelectric properties (Seebeck coefficients, electrical and thermal diffusivities, heat capacities) were measured between room temperature and 1073 K. CaB 6 , SrB 6 , BaB 6 and the ternary hexaborides Ca x Sr 1−x B 6 , Ca x Ba 1−x B 6 , Sr x Ba 1−x B 6 (x = 0.25, 0.5, 0.75) are n-type conducting compounds over the whole compositional and thermal ranges. The values of the figure of merit ZT for CaB 6 (ca. 0.3 at 1073 K) were found to be significantly increased compared to earlier investigations which is attributed to the densification process. - Highlights: • Solid solutions of alkaline earth hexaborides were synthesized. • High-temperature thermoelectric properties of mixed calcium borides are excellent. • Spark plasma source densification results in high ZT values. • Borides are rare-earth free and refractory materials

  8. Layered SmBaCuCoO5+δ and SmBaCuFeO5+δ perovskite oxides as cathode materials for proton-conducting SOFCs

    International Nuclear Information System (INIS)

    Nian Qiong; Zhao Ling; He Beibei; Lin Bin; Peng Ranran; Meng Guangyao; Liu Xingqin

    2010-01-01

    A dense BaCe 0.8 Sm 0.2 O 5+δ (BCS) electrolyte was fabricated on a porous anode by in situ drop-coating to develop a simple and cost-effective route to fabricate proton-conducting solid oxide fuel cells (SOFCs). Layered perovskite-structure oxides SmBaCuCoO 5+δ (SBCC) and SmBaCuFeO 5+δ (SBCF) were prepared and the electrical conductivity, the thermal expansion coefficient and electrochemical performance were investigated as potential cathode materials for proton-conducting SOFCs. Thermal expansion coefficients of SBCC and SBCF were suitable for BCS electrolyte and the electrical conductivity of the SBCC is higher than that of the SBCF. The maximum power density of 449 mW cm 2 and 333 mW cm 2 at 700 o C were obtained for the SBCC/BCS/NiO-BCS and SBCF/BCS/NiO-BCS cells, respectively. The interfacial polarization resistances for SBCC and SBCF cathode are as low as 0.137 Ω cm -2 and 0.196 Ω cm -2 at 700 o C, respectively. The results indicate that the SBCC and SBCF are promising cathode materials for proton-conducting SOFCs.

  9. Optimization in the preparation of the YBa2Cu3O7-δ compound using BaCO3 and BaO2 reagents

    International Nuclear Information System (INIS)

    Bustamante D, A.; Flores S, J.

    2004-01-01

    The traditional superconductor YBa 2 Cu 3 O 7-δ (Y123) has an orthorhombic crystalline structure with spatial group Pmmm and its critical temperature is 90K. The literature reports the use of reagent BaCO 3 for the preparation by the solid state reaction which requires one calcination and two thermal treatments in oxygen flow at 950 o C. In this work we report the comparison in the preparation of Y123 using the BaO 2 reagent as another possibility for preparation; in this case we have used only two thermal treatments in oxygen flow at 950 o C; therefore reducing the costs in preparation. The powder XRD pattern of samples prepared with BaO 2 confirm a well crystallized phase an the diffraction lines of the main phase can be indexed with an orthorhombic unit cell. The ac susceptibility measurement in the range 5-100 K using a Quantum Design (SQUID) magnetometer for two samples confirms the superconductor behavior with critical temperature Tc ≅ 91 K. The critical temperatures for these systems were found taken account the derivatives of the susceptibility curves. Scanning Electron Microscopy (SEM) confirms the good behavior of the grains corresponding to both methods. (orig.)

  10. Rattling of Ba-atoms in Ba8ZnxGe43-5x/8([]3-3x/8)

    International Nuclear Information System (INIS)

    Melnychenko, N.; Grytsiv, A.; Rotter, M.; Rogl, P.; Devishvili, A.

    2006-01-01

    Full text: In order to improve the figure of merit of thermoelectric materials, one of the key parameters to be minimized is the lattice thermal conductivity. It is thus essential for the design of new thermoelectric materials to understand the lattice dynamics, especially the scattering mechanism of low energy phonons. The present paper describes formation, phase relations at subsolidus temperatures as well as at 800 o C, crystal chemistry and physical properties of a series of ternary clathrates as part of the solid solution, Ba 8 Zn x (Ge 43-5x/8[]3-3x/8 ), deriving from binary Ba 8 Ge 43 []3 with a solubility limit of 8 Zn per formula unit at 800 o C. Structural investigations in all cases confirm cubic primitive symmetry with a lattice parameter a ∼ 1.1 nm consistent with the space group type Pm-3n. Studies of transport coefficients evidence electrons as the majority charge carriers in the systems. Thermal conductivity exhibits a pronounced low temperature maximum, dominated by the lattice contribution, while at higher temperatures the electronic part gains weight. Inelastic neutron scattering experiments are used to study the phonon spectrum for Ba 8 Zn 8 Ge 38 . (author)

  11. Dosimetry of ultraviolet radiation with BaHfO{sub 3} powders; Dosimetria de radiacion ultravioleta con polvos de BaHfO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Barrera A, A. A.; Aguilar D, G. A.; Guzman M, J.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, Col. Irrigacion, 11500 Ciudad de Mexico (Mexico); Ceron R, V., E-mail: abalba1@hotmail.com [Universidad de Guanajuato, 37670 Leon, Guanajuato (Mexico)

    2016-10-15

    Ceramic materials based on pure barium hafnate (BaHfO{sub 3}) have been obtained as a powder by the co-precipitation method. The powders obtained have a cubic structure that favors the thermoluminescent and optical properties, through which a better detection of the non-ionizing radiation is allowed. With these powders various tests were performed in the ultraviolet range at different exposure times. These thermoluminescent (Tl) studies were carried out using a Tl 3500 hand held reader which yielded a brightness curve that ranged from room temperature to the 350 degrees Celsius. This BaHfO{sub 3} response exhibits a broad brightness curve with a single peak centered around 225 degrees Celsius. Finally, is reported that there are materials of barium hafnate (BaHfO{sub 3}) doped with some rare earths (Eu, Tb) which, instead of improving the performance of the powders, decrease it, so that the use of intrinsic barium hafnate is the most appropriate. (Author)

  12. Superconductivity and fluctuations in Ba_1_–_pK_pFe_2As_2 and Ba(Fe_1_–_nCo_n)_2As_2

    International Nuclear Information System (INIS)

    Böhm, T.; Hosseinian Ahangharnejhad, R.; Technical University of Munich, Garching

    2016-01-01

    In this paper, we study the interplay of fluctuations and superconductivity in BaFe_2As_2 (Ba-122) compounds with Ba and Fe substituted by K (p doping) and Co (n doping), respectively. To this end, we measured electronic Raman spectra as a function of polarization and temperature. We observe gap excitations and fluctuations for all doping levels studied. The response from fluctuations is much stronger for Co substitution and, according to the selection rules and the temperature dependence, originates from the exchange of two critical spin fluctuations with characteristic wave vectors (±π,0) and (0,±π). At 22% K doping (p = 0.22), we find the same selection rules and spectral shape for the fluctuations but the intensity is smaller by a factor of 5. Since there exists no nematic region above the orthorhombic spin-density-wave (SDW) phase, the identification of the fluctuations via the temperature dependence is not possible. The gap excitations in the superconducting state indicate strongly anisotropic near-nodal gaps for Co substitution which make the observation of collective modes difficult. The variation with doping of the spectral weights of the A_1_g and B_1_g gap features does not support the influence of fluctuations on Cooper pairing. Thus, the observation of Bardasis–Schrieffer modes inside the nearly clean gaps on the K-doped side remains the only experimental evidence for the relevance of fluctuations for pairing.

  13. Three new chalcohalides, Ba4Ge2PbS8Br2, Ba4Ge2PbSe8Br2 and Ba4Ge2SnS8Br2: Syntheses, crystal structures, band gaps, and electronic structures

    International Nuclear Information System (INIS)

    Lin, Zuohong; Feng, Kai; Tu, Heng; Kang, Lei; Lin, Zheshuai; Yao, Jiyong; Wu, Yicheng

    2014-01-01

    Highlights: • Three new chalcohalides: Ba 4 Ge 2 PbS 8 Br 2 , Ba 4 Ge 2 PbSe 8 Br 2 and Ba 4 Ge 2 SnS 8 Br 2 have been synthesized. • The MQ 5 Br octahedra and GeQ 4 tetrahedra form a three-dimensional framework with Ba 2+ in the channels. • Band Gaps and electronic structures of the three compounds were studied. - Abstract: Single crystals of three new chalcohalides: Ba 4 Ge 2 PbS 8 Br 2 , Ba 4 Ge 2 PbSe 8 Br 2 and Ba 4 Ge 2 SnS 8 Br 2 have been synthesized for the first time. These isostructural compounds crystallize in the orthorhombic space group Pnma. In the structure, the tetra-valent Ge atom is tetrahedrally coordinated with four Q (Q = S, Se) atoms, while the bi-valent M atom (M = Pb, Sn) is coordinated with an obviously distorted octahedron of five Q (Q = S, Se) atoms and one Br atom, showing the stereochemical activity of the ns 2 lone pair electron. The MQ 5 Br (M = Sn, Pb; Q = S, Se) distorted octahedra and the GeQ 4 (Q = S, Se) tetrahedra are connected to each other to form a three-dimensional framework with channels occupied by Ba 2+ cations. Based on UV–vis–NIR spectroscopy measurements and the electronic structure calculations, Ba 4 Ge 2 PbS 8 Br 2 , Ba 4 Ge 2 PbSe 8 Br 2 and Ba 4 Ge 2 SnS 8 Br 2 have indirect band gaps of 2.054, 1.952, and 2.066 eV respectively, which are mainly determined by the orbitals from the Ge, M and Q atoms (M = Pb, Sn; Q = S, Se)

  14. Electronic structure of BaFe2As2 as obtained from DFT/ASW first-principles calculations

    KAUST Repository

    Schwingenschlö gl, Udo; Di Paola, Cono

    2010-01-01

    We use ab-initio calculations based on the augmented spherical wave method within density functional theory to study the magnetic ordering and Fermi surface of BaFe2As2, the parent compound of the hole-doped iron pnictide superconductors (K,Ba)Fe2As

  15. Determination of radium isotopes by BaSO4 coprecipitation for the preparation of alpha-spectrometric sources

    International Nuclear Information System (INIS)

    Lozano, J.C.; Fernandez, F.; Gomez, J.M.G.

    1997-01-01

    A coprecipitation procedure for the preparation of α-spectrometric sources for radium, using BaSO 4 as carrier, has been applied to the determination of alpha radium isotopes in water samples. The use of 133 Ba as a suitable tracer for radium determination and possible losses of radon isotopes from the sources are studied and discussed. (author)

  16. APOLIPOPROTEIN B/A1 IS INDEPENDENTLY ASSOCIATED WITH CAROTID INTIMAL-MEDIAL THICKNESS IN CHRONIC KIDNEY DISEASE PATIENTS.

    Directory of Open Access Journals (Sweden)

    Il Young Ki

    2012-06-01

    In conclusion, this study showed serum apo B/A1 ratio was independently associated with CIMT only in CKD group, not in non-CKD group. Because CIMT is a strong predictor of CVD, the result of this study demonstrates serum apo B/A1 ratio could be included in cardiovascular risk stratification in CKD patients

  17. The volatile pivalates of Y, Ba and Cu as prospective precursors for metal-organic chemical vapour deposition

    Energy Technology Data Exchange (ETDEWEB)

    Iljina, E. (Dept. of Chemistry, Moscow State Univ. (Russian Federation)); Korjeva, A. (Dept. of Chemistry, Moscow State Univ. (Russian Federation)); Kuzmina, N. (Dept. of Chemistry, Moscow State Univ. (Russian Federation)); Troyanov, S. (Dept. of Chemistry, Moscow State Univ. (Russian Federation)); Dunaeva, K. (Dept. of Chemistry, Moscow State Univ. (Russian Federation)); Martynenko, L. (Dept. of Chemistry, Moscow State Univ. (Russian Federation))

    1993-04-15

    The volatile pivalates of Y, Ba and Cu were synthesized and characterized by chemical and thermogravimetric analysis, IR spectroscopy, X-ray diffraction and mass spectrometry. The volatilities of metal pivalates was studied; the vapour pressures, thermodynamic characteristics and rates of sublimation were investigated. The volatile pivalates of Y, Ba and Cu are new prospective accessible compounds. (orig.)

  18. Formation of the 1:2:3 structure in Y-Ba-Cu(Fe)-O system studied by Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Valko, P.; Miglierini, M.; Sitek, J.; Hucl, M.; Gruskova, A.

    1990-01-01

    Annealing time and temperature dependence of Y, Ba, Cu, Fe nitrade mixture towards new phases creation was revealed by Moessbauer spectroscopy. The observed changes can be assigned to chemical decomposition of corresponding nitrades and creation of intermedial and final Y 1 Ba 2 (Cu 0.95 Fe 0.05 ) 3 O x phase. (orig.)

  19. Baumot BA-B Diesel Particulate Filter with Pre-Catalyst (ETV Mobile Source Emissions Control Devices) Verification Report

    Science.gov (United States)

    The Baumot BA-B Diesel Particulate Filter with Pre-Catalyst is a diesel engine retrofit device for light, medium, and heavy heavy-duty diesel on-highway engines for use with commercial ultra-low-sulfur diesel (ULSD) fuel. The BA-B particulate filter is composed of a pre-catalyst ...

  20. Electronic and magnetic structure of BaCoO2 as obtained from LSDA and LSDA+U calculations

    KAUST Repository

    Nazir, Safdar; Zhu, Zhiyong; Pulikkotil, Jiji Thomas Joseph; Schwingenschlö gl, Udo

    2011-01-01

    Density functional theory is used to study the structural, electronic, and magnetic properties of BaCoO2. Structural relaxation for different collinear magnetic configurations points to a remarkable magneto-elastic coupling in BaCoO2. Although we