Effect of konjac glucomannan on sodium alginate membrane

This paper introduces a blended membrane which is prepared by coagulation of sodium alginate and konjac glucomannan(KGM) in an aqueous solution, and studies the effect of different concentrations of KGM on sodium alginate films. The structural characterization of prepared blend film was implemented by scanning electron microscopy(SEM) and Fourier transform infrared spectroscopy(FT-IR), and the optimum ratio was determined by comparing fracture elongation, moisture absorption and moisture retention. The results indicate that the two polysaccharide molecules, sodium alginate and KGM, in the blend membrane have a good compatibility. The surface of blend film is smooth and uniform. The addition of KGM can significantly improve the moisture absorption and moisture retention performance of sodium alginate film, and its mechanical performance is also improved to some extent. The ratio of sodium alginate and KGM is 3.2∶1.5.     

The Edge-pancyclicity of Generalized Hypercubes

Generalized hypercubes （denoted by Q（d1,d2,... ,dn）） is an important network topology for parallel processing computer systems. Some methods of forming big cycle from small cycles and links have been developed. Basing on which, we has proved that in generalized hypercubes, every edge can be contained on a cycle of every length from 3 to IV（G）I inclusive and all kinds of length cycles have been constructed. The edgepanciclieity and node-pancilicity of generalized hypercubes can be applied in the topology design of computer networks to improve the network performance.     

硅钼黄光度法测定油田产出水中低聚硅

建立了一种硅钼黄光度法测定三元复合驱产出水中低聚硅（单硅及一、二聚硅）的方法,研究了复杂体系三元复合驱产出水中低聚硅的定量分析．在pH值为1～2,波长在400nm处测定,硅含量在0～250mg·L^-1范围内呈良好的线性关系．此硅钼黄光度法简单易行,测定范围宽,具有一定的实用价值．     

沉淀法制备氧化铝的相变过程

为获得沉淀法制备氧化铝的相变过程及微观形貌,将NaOH溶液与AlCl3溶液混合,在pH值6～9内,制备三羟铝石,将其加热到1 200℃获得了氧化铝粉体。经TG-DTA、XRD、FTIR光谱、SEM等测试手段分析,300℃煅烧后获得了单水铝石,然后依次获得γ-Al2O3、δ-Al2O3、θ-Al2O3过渡相,并且在1200℃煅烧后获得了纯相α-Al2O3。TG-DTA表征,粉体在273℃脱水显著,在1000℃后θ-Al2O3向α-Al2O3形核并长大,需要较大激化能而放热,1 200℃煅烧后FTIR透过光谱表征α-Al2O3的典型的AlO6八面体结构引发形成640～590 cm^-1的两个吸收峰。制备的三羟铝石呈亚微米的团絮状,而纯相α-Al2O3呈现亚微米的聚集体颗粒形貌。这为改进陶瓷性能提供工艺参数依据。     

基于P2P的可靠全序组通信系统

提出了一种适用于Internet环境下的大规模组通信系统,包含扩展Pastry协议(EPP)和基于环的可靠组通信协议(RRGP).EPP通过已知的节点最优路径情况动态地预测网络真实路径的长度,建立一个接近实际网络节点分布的计算模型,并利用聚类预测算法划分网络节点,使同一分组的节点之间的距离最小化,提供更加合理的路由选择.RRGP在EPP的基础上实现了核心多播环模型,从而确定了多播消息序,实现了消息的全序传递,并采用缓存/重发机制,保证了消息传递的可靠性.     

各向异性功能梯度材料板Ⅰ型裂纹断裂力学研究

针对材料参数在厚度方向可按任意函数连续变化的梯度材料,给出了一个新的分层模型．恰当选取分析平面,使材料参数沿2轴方向按任意函数形式连续变化,利用该模型并借助复变函数方法,研究了各向异性功能梯度材料的Ⅰ型裂纹平面断裂问题．首次推出了材料参数沿梯度方向按任意函数连续变化的各向异性功能梯度材料板Ⅰ型裂纹尖端的应力场、位移场和梯度应力强度因子的理论计算公式．结果显示裂纹尖端应力场同样具有r反平方根的奇异性,因此可以运用广泛应用于均匀材料中的断裂力学方法来研究各向异性功能梯度材料问题．     

Sex-related gene and sex identification of Crested IbisNipponia nippon (Ciconiiformes: Threskiornithidae)

The Crested Ibis (Nipponia nippon) is a critical endangered species of the world. At present, a reintroduction program will be conducted to save this species essentially. However, because the Crested Ibise is a sexual alike bird, it is very difficult to identify the sex from the morphological character. In order to identify the sex easily and select the right individuals for captive breeding and reintroduction, the sex related gene on W chromosome was amplified and the sex of three Crested Ibises were also identified in the present study. The 262bp fragment was also sequenced, and we found that there were 13 different nucleotide sites with 2.25 of transition/transversion based on the comparison with that of the Oriental White Stork. The sequence will also provide a theoretic base for further designing specific primer for sex related gene in the Crested Ibis.     

广西恭城-栗木断裂带的分形分析

恭城－栗木断裂带的分形分析结果是：整个断裂带的分维值D接近1．5。与整个华南地区线性构造的分维值（D＝1．35）相比,该断裂带属结构较复杂、活动性较强的一类,但总体上它已趋于成熟。在恭城－栗木断裂带中,南北向断裂的分维值远大于北东向和东西向裂断裂的分维值,这说明整个断裂带是南北向断裂为主。     

Structural basis of water-specific transport through the AQP1 water channel.

Water channels facilitate the rapid transport of water across cell membranes in response to osmotic gradients. These channels are believed to be involved in many physiological processes that include renal water conservation, neuro-homeostasis, digestion, regulation of body temperature and reproduction. Members of the water channel superfamily have been found in a range of cell types from bacteria to human. In mammals, there are currently 10 families of water channels, referred to as aquaporins (AQP): AQP0-AQP9. Here we report the structure of the aquaporin 1 (AQP1) water channel to 2.2 A resolution. The channel consists of three topological elements, an extracellular and a cytoplasmic vestibule connected by an extended narrow pore or selectivity filter. Within the selectivity filter, four bound waters are localized along three hydrophilic nodes, which punctuate an otherwise extremely hydrophobic pore segment. This unusual combination of a long hydrophobic pore and a minimal number of solute binding sites facilitates rapid water transport. Residues of the constriction region, in particular histidine 182, which is conserved among all known water-specific channels, are critical in establishing water specificity. Our analysis of the AQP1 pore also indicates that the transport of protons through this channel is highly energetically unfavourable.     

用于汽车轮胎力学特性研究的试验拖车

研究汽车在各种路面高速运动状态下的轮胎力学特性,为汽车的结构设计与改进提供试验数据。利用研制的试验拖车,通过在各种路面上的道路试验进行轮胎力学特性的各种研究,由此得到各种参数之间的相互关系及影响。试验结果表明,试验数据与理论分析基本吻合,证明拖车能够用于汽车轮胎力学特性的研究。