爆炸排淤填石法中淤泥的本构模型

以爆炸排淤填石法为背景,对不同应变率阶段淤泥的本构模型进行了分析,利用ANSYS/LS-DYNA动态有限元分析程序对所选择的模型进行验证和确认.计算和分析结果表明:在形成爆炸空腔的高应变率阶段,淤泥表现为理想不可压缩流体的性质;在小药量小抵抗线条件下,甚至在淤泥自重作用下的较低应变率变形阶段,其黏性效应也可以忽略不计.

Ni^2＋掺杂透明ZnO-Al2O3-SiO2系微晶玻璃的光学性质

采用传统熔融冷却的方法制备了透明Ni^2＋掺杂ZnO-Al2O3-SiO2系玻璃，结合X-射线、吸收和荧光等测试手段，研究了不同热处理温度对Ni^2＋掺杂透明ZnO-Al2O3-SiO2系微晶玻璃光学性质的影响。由X-射线衍射谱鉴定出微晶玻璃中析出的晶相为ZnAl2O4微晶，其尺寸在13nm以下。玻璃中没有发现近红外发光，而在微晶玻璃中存在宽带近红外发光，其可归属为八面体六配位Ni^2＋离子的^3T2g（^3F）激发态向^3A2g（^3F）基态的跃迁。随热处理温度升高发光强度增强，而发射峰位则发生蓝移；荧

厄米-高斯光束中带宽对横向强度分布均匀性的影响

使用惠更斯-菲涅耳衍射积分和傅里叶变换，推导了横向模式为厄米高斯的激光束通过硬边光阑的传输表达式。利用所得公式通过数值计算详细分析了光束的频带宽度对光束横向强度分布的影响。分析发现激光束通过硬边光阑后会出现大量的强度尖峰，引起近场的强度分布不均匀。然而，当带宽增加时，强度尖峰的数量减少，幅度减小，光束的均匀性得到改善。在远场，光束的横向强度分布没有强度尖峰出现，但宽度随带宽的增加而减小。因此带宽增加会带来近场强度匀滑化和远场光束宽度变窄的效应。另外，数值结果表明带宽对模指数为1和2的厄米-高斯光束的强度分

独龙江流域冬季鱼类多样性及其分布特点

2004年10—11月,对独龙江的鱼类资源进行了调查,根据不同的海拔及生境在整个独龙江流域共计设置了26个采样点,采集鱼类标本883号。对各采集点渔获物的统计分析的结果显示:(1)独龙江干流、支流的鱼类生物量、物种多样性,随海拔的上升呈下降趋势;(2)干流的Shannon-Wiener指数、物种均匀性指数均高于支流;(3)除了独龙裂腹鱼、大鳍异齿在整个独龙江流域均有分布外,其余5种鱼类的分布与海拔因子的变化有明显的关系。

流动注射分离-原子吸收光谱法测定底泥中生物可利用态Cr(Ⅵ)和Cr(Ⅲ)

湖泊底泥中生物可利用态铬是对湖泊生态环境最有影响的铬赋存形态,分别用弱有机酸或螯合缓冲剂对底泥中生物可利用态铬进行萃取分离。在流动注射系统中,分别以串联在流路中阴、阳离子交换微型柱分离,NH4NO3+抗坏血酸和H2SO4两种洗脱液同时逆向洗脱,实现了对底泥可利用态铬中Cr(Ⅵ)和Cr(Ⅲ)同时在线分离和原子吸收光谱法测定。交换时间2min,洗脱50s,Cr(Ⅵ)和Cr(Ⅲ)回收率分别为85.4%~94.8%和96.7%~106%。本方法对实际样品中不同价态铬进行测定,铬回收率可达95%。Cr(Ⅵ)和Cr(

鲤鱼sGnRH基因克隆及其在成熟个体的表达分析

采用RACE方法 ,从鲤鱼脑组织克隆了两个差异的sGnRH(salmonGnRH ,[Trp7Leu8]GnRH)cDNAs ,即cDNA1和cDNA2 ,其长度分别为 393和 4 78bp。两个cDNAs都包括一个 2 85bp开放阅读框 ,编码的sGnRH前体为 94个氨基酸残基 ,由一个信号肽、sGnRH十肽和一个由蛋白水解位点 (Gly Lys Arg)连接的促性腺激素释放激素相关肽共 3部分组成。用内含子捕获得到相应的两个差异sGnRH基因 ,即sGnRHgene1和 gene2 ,其基本结构

植物的冗余及其生态学意义 Ⅰ.大型水生植物生长冗余研究

通过水生群落中常见优势种凤眼莲 ( Eichhornia crassipes)根系的去除实验证明了生长冗余的存在 ,并在此基础上对大型水生植物的竞争力、“浮游生物的悖论”及水生群落稳定性的产生与维持作了新的阐述。根系去除实验表明 :群体中凤眼莲植株的根系生长冗余较单株生长时为多 ;这些冗余根系的去除不会对整个植株的生长发育产生明显影响 ;群体中植株根系冗余能够加强植株的竞争能力。生长冗余以及建立在生长冗余基础上的更高层次的冗余结构与生物多样性具有一定的相关性 ,也是生物进化中自然选择的真正对象。据此提出了

Isolation of Y- and X-linked SCAR markers in yellow catfish and application in the production of all-male populations

P>Sex controls have been performed in some farmed fish species because of significant growth differences between females and males. In yellow catfish (Pelteobagrus fulvidraco), adult males are three times larger than female adults. In this study, six Y- and X-linked amplified fragment length polymorphism fragments were screened by sex-genotype pool bulked segregant analysis and individual screening. Interestingly, sequence analysis identified two pairs of allelic genes, Pf33 and Pf62. Furthermore, the cloned flanking sequences revealed several Y- and X-specific polymorphisms, and four Y-linked or X-linked sequence characterized amplified region (SCAR) primer pairs were designed and converted into Y- and X-linked SCAR markers. Consequently, these markers were successfully used to identify genetic sex and YY super-males, and applied to all-male population production. Thus, we developed a novel and simple technique to help commercial production of YY super-males and all-male populations in the yellow catfish.

Discovery of a male-biased mutant family and identification of a male-specific SCAR marker in gynogenetic gibel carp Carassius auratus gibelio

Gibel carp ( Carassius auratus gibelio) is a uniquely gynogenetic species with a minor ratio of males in natural habitats, but its male origin and sex determination mechanisms have been unknown. In this study, a male-biased mutant family was discovered from the gynogenetic gibel carp, and a male-specific SCAR marker was identified from the mutant family. Normal spermatogenesis was observed in the male testes by immuno. fluorescence histochemistry. Nearly identical AFLP profiles were observed between males and females, but a male-specific 86 bp AFLP fragment was screened by sex-pool bulked segregant analysis and individual screening. Based on the male-specific AFLP fragment, a total of 579 bp sequences were cloned by genome walking. Subsequently, a male-specific SCAR marker was designed, and the male-specific DNA fragment was confirmed to be steadily transmitted to the next generation and consistently detected only in males. (C) 2009 National Natural Science Foundation of China and Chinese Academy of Sciences. Published by Elsevier Limited and Science in China Press. All rights reserved.

鄂尔多斯地区锦鸡儿资源化途径与关键技术

锦鸡儿灌木适生于鄂尔多斯高原，资源丰富，萌发力强，粗蛋白和钙含量高，锦鸡儿的饲用化开发是当地羊绒业实现可持续发展的根本对策之一。为此进行了锦鸡儿资源评估并应用正交、均匀和配方设计对康氏木霉，黑曲霉产酶发酵和锦鸡儿同步酶解发酵进行了实验研究。结果表明：（1）锦鸡儿叶部约占地上干生物质的20％；4年是锦鸡儿生长的临界点，4年后粗纤维含量骤升，木质化程度加剧。故锦鸡儿应在花期后、落叶前的深秋、每4年贴地平茬一次。（2）开发出康氏木霉纤维素酶、黑曲霉果胶酶的优化产酶培养基配方与固态发酵工艺，二者放大发酵复合酶的活力超过国内同类商品，成本仅537.16元／（tDM）、1072.10元／（tDM）。舍饲时添加复合酶的山羊仅增重可增收138元（年·只）。（3）在同步酶解发酵锦鸡儿生物质时，乳酸菌长期发酵产生的乳酸会降低pH值并对酶解粗纤维产生抑制；复合酶中FPA:CMCase：棉花酶： β-glucosidase活力比以0.6:1:0.3:1为宜。（4）中间锦鸡儿资源集中在干草原区，4年轮流平茬时每年收获的生物质可供146万只羊越冬，经复合酶发酵后能满足191万只羊越冬期间对粗蛋白的需求。本研究有助于西部不发达牧区实现社会、经济和环境的可持续发展。