微/纳米氧化锌（ZnO）的生长、性质及其应用研究

纳米氧化锌（ZnO）是一种直接宽带隙半导体材料，室温下其禁带隙宽为本3.37 eV，激子束缚能为60 meV。纳米ZnO有明显的尺寸效应、表面和界面效应等，物理化学性能优越。在压电材料、铁电材料、平面显示、表面声波、传感器、场发射器件、激光、光催化等方面有着广泛的用途。近年来，对纳米ZnO材料的研究成为国内外的一个热点。 本论文研究了用化学气相沉积（CVD）法制备微/纳米ZnO材料。通过控制实验条件，合成了多种特殊结构和形貌的微/纳米ZnO材料，并用扫描电子显微镜（SEM）、高分辨率透射电镜（HR-TEM）、X-射线衍射仪（XRD）、Raman光谱和光致发光（PL）等对材料的结构和光学性能进行了表征。采用CVD法，在温度为630 °C，氧气流量为15 sccm，氩气流量为300 sccm的条件下，制备了一种纳米带冠四足状ZnO（T-ZnO）。此结构ZnO材料的每根足顶端均有一规则的六方帽形结构，具有很大的比表面积。实验结果表明：合成的ZnO材料为纤维锌矿结构单晶，并且沿着(0001)方向生长；室温下的PL谱有两个激发峰，一个是在393 nm处相对较弱的近带紫外峰，另一个是在511 nm处强峰。而材料在600 °C下氧气中退火30 min后，511 nm附近的绿光激发辐射峰则基本消失了，这说明在511 nm处的绿光激发辐射峰可能是由于氧空位引起的。此外，通过改变实验条件，还得到了其他多种结构的微/纳米ZnO材料。 通过大量实验，找到了一种在低温下合成微/纳米ZnO材料的新方法，即水蒸气氧化法。用ZnI2作为锌源，水蒸气作为氧化剂，实验温度在300～500 °C范围内，大大低于通常CVD法的500～1500 °C。采用此法，用硅做基底，得到了一系列有趣的实验结果，大多数情况下ZnO纳米晶自组装成很规则的圆。而在瓷舟中收集到的纳米ZnO跟普通CVD法结果相似，可以得到锥状、棒状等结构的纳米晶，但其生长方式与硅基底上的有很大差别。此外，用水蒸气氧化法，还实现了ZnO纳米晶在碳纳米管（CNTs）上的直接生长，而且其PL性能增强，这可能是纳米ZnO和CNTs相互耦合的结果。在700 °C温度下，以锌粉和ZnI2作为锌源，用水蒸气作为氧化剂，在硅基底的正反面分别得到了纳米棒和纳米推子阵列。此外，还对水蒸气氧化法的化学反应机理进行了分析，实验结果证明：固态ZnI2在受热和一定真空度下先蒸发成ZnI2分子，ZnI2分子遇到水蒸气发生反应生成偶极ZnO分子，这些ZnO偶极分子在硅基底上通过静电力自组装成特殊的几何形状。 此外，还通过分子动力学模拟的方法，对材料的力学性能进行了研究，得到了ZnO的弹性常数和体弹性模量，模拟值跟其他研究人员的实验和模拟结果吻合得很好，并估出算了ZnO晶体的表面能和断裂韧性。 本论文还对制备材料的光催化性能进行了系统的研究，采用CVD法制备ZnO，对铬黑T（EBT）进行光催化降解实验。通过正交实验方法，得到了ZnO催化降解EBT的最佳工艺条件，即催化剂用量为5 g/L，光照强度为120 W，反应温度为20 °C，反应时间为120 min，EBT浓度为10 mg/L，溶液pH值为4。 在最佳实验条件下，20分钟内有95%的EBT被降解完，30分钟内则全部降解。因此，ZnO在EBT的降解中催化效率很高，在废水处理中具有潜在的应用前景。

Evaluation of salmon and steelhead spawning habitat quality in the South Fork Trinity River Basin, 1997

Sediment sampling was used to evaluate chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) spawning habitat quality in the South Fork Trinity River (SFTR) basin. Sediment samples were collected using a McNeil-type sampler and wet sieved through a series of Tyler screens (25.00 mm, 12.50 mm, 6.30 mm, 3.35 mm, 1.00 mm, and 0.85 mm). Fines (particles < 0.85 mm) were determined after a l0-minute settling period in Imhoff cones. Thirteen stations were sampled in the SFTR basin: five stations were located in mainstem SFTR between rk 2.1 and 118.5, 2 stations each were located in EF of the SFTR, Grouse Creek, and Madden Creek, and one station each was located in Eltapom and Hayfork Creeks. Sample means for fines(particles < 0.85 mm) fer SFTR stations ranged between 14.4 and 19.4%; tributary station sample mean fines ranged between 3.4 and 19.4%. Decreased egg survival would be expected at 4 of 5 mainstem SFTR stations and at one station in EF of SFTR and Grouse Creek where fines content exceed 15%. Small gravel/sand content measured at all stations were high, and exceed levels associated with reduced sac fry emergence rates. Reduction of egg survival or sac fry emergence due to sedimentation in spawning gravels could lead to reduced juvenile production from the South Fork Trinity River. (PDF contains 18 pages.)

Cooperative artificial propagation programs for salmon and steelhead, 1995-1996

Fifteen cooperative fish rearing and planting programs for salmon and steelhead were active from July 1, 1995 through June 30, 1996. For all programs, 134,213 steelhead trout,(Oncorhynchus mykiss), 7,742,577 chinook salmon,(~ tshawytscha),and 25,075 coho salmon(~ kisutch) were planted. (PDF contains 26 pages.)

Cooperative artificial propagation programs for salmon and steelhead, 1996-1997

Fourteen cooperative fish rearing and planting programs for salmon and steelhead were active from July 1, 1996 through June 30, 1997. For all programs, 208,922 steelhead trout, (Oncorhynchus mykiss), 10,334,457 chinook salmon,(O. tshawytscha),and 60,681 coho salmon(O. kisutch) were planted. (PDF contains 24 pages.)

Jarduera fisikoak adineko pertsona autonomoen osasunean duen eragina

294 p. : il.

Diário da Constituinte [gravação de vídeo] : [programa n. 518]

Constituintes negros formam uma delegação para visita à Africa do Sul observar as condições de segregação da população negra daquele país, o Aparthaid. A visita seria realizada no intervalo entre o primeiro e o segundo turno de votação. A Constituinte retoma a votação do título VI da futura Carta, que trata do Sistema Tributário no país. Foi votada a contribuição de melhoria. Cada Município vai poder cobrar dos interessados uma contribuição para obras de melhorias, como asfalto de rua, pontes e estradas. O tema polêmico da Sessão foi o parágrafo primeiro do artigo 184, que permite a estados e municípios, a cobrança de 5% sobre o imposto de renda que incidir em ganhos de capital, para fazer face a obras estaduais e municipais. Presidente da Constituinte fez um balanço dos dispositivos votados e faz apelo para que todos estejam presentes nas sessões subsequentes.

30. Sitzung des Codex Alimentarius Komitees für Fische und Fischerzeugnisse in Agadir, Marokko, vom 28.9. bis 2.10.2009

The Codex Committee on Fish and Fishery Products held its 30th Session in Agadir, Morocco from 28 September to 2 October 2009, at the kind invitation of the Government of Morocco. The Session was chaired by Dr Bjørn Røthe Knudsen, Regional Director of the Norwegian Food Safety Authority. The Session was attended by 218 delegates representing 78 Member States, one Member Organization (EC) and 1 international organization.

30. Jahrestagung der "WestEuropean Fish Technologists' Association" in Torshavn, Faroer

In der West European Fish Technologists’ Association (WEFTA) arbeiten zahlreiche europäische Institute zusammen, die sich mit Fisch als Lebensmittel oder mit Fischtechnologie befassen. Ziel der WEFTA ist es, einen Austausch von Informationen über Forschung und ihre Ergebnisse europaweit möglich zu machen. Die Jahrestagungen sind eine gute Gelegenheit, Einblick in die Arbeiten anderer Institutionen zu erhalten und europäische Kontakte zu knüpfen. Die Tagungen sind besonders interessant für junge Wissenschaftler, die hier ihre Ergebnisse einem grösseren Publikum vorstellen konnen.

La praxeología motriz aplicada al fútbol

XX,560 p.

El pescado en la comedia griega

Presentado en el Congreso Internacional "Sociedad, política y literatura. Comedia griega antigua", organizado por la Universidad de Salamanca y celebrado en Salamanca los días 26 a 30 de noviembre de 1996.

Oceanographic atlas of habitats of larval tunas in the Pacific Ocean off the Azuero Peninsula, Panama

This report presents maps and statistics of summaries by season (dry and wet) of temperature, salinity, density, oxygen concentration, and oxygen saturation at six depths (0, 3, 10, 30, 50, and 100 m) in the Pacific Ocean off the Azuero Peninsula, Panama. Profiles made with a conductivity-temperature-pressure (CTD) probe on a 14-station grid from July 1989 through August 1991 provide the basis for these products. (PDF contains 37 pages.)

让舰艇练就护体内功:抗冲击能力——中国舰船史600年和60年的思考

@@ 2009年4月23日,在中国人民海军创立60周年之际,中央军委主席胡锦涛在青岛奥帆中心附近海域检阅了多国海军舰队.阅兵开始,中国海军的导弹驱逐舰、护卫舰、核潜艇跃现海面,举世瞩目,见证了中国"建设一支强大的人民海军"的步伐.

Mulier virilis. la masculinización del modelo femenino en el cristianismo primitivo: de Tecla a Melania Junior

131 p. - E-mail del autor: ikmagro88@gmail.com