Ti-V基贮氢合金电极电化学性能的影响因素

研究了粉体粒度、导电镍粉及工作温度对合金电极Ti0 .1 7Zr0 .0 8V0 .35Ni0 .1 0 Ni0 .30 放电性能的影响。结果表明 :随着合金粒度的减小 ,放电容量有所增加 ,但放电容量随着循环数的增加而有所降低 ;而导电羰基镍粉含量的变化对合金电极的放电容量几乎没有影响。随着合金电极工作温度的增加 ,合金电极的循环稳定性、充、放电电压均有所降低。温度明显地影响Ti V基贮氢合金电极中V在电介质溶液中的溶解。

The effect of some factors on the electric properties of rare earth complex oxide

The rare earth complex oxides with different types have been synthesized. Their structures and electric properties have been investigated. According to our experimental results, the effects of the outest shell electronic configuration, electron spin state, electron transport path and formation of cluster on the electric properties of rare earth complex oxides have been summarized. When the electrons in the outest shell of the central metallic ion are unpair, and the outest shell is not half-filled, the electric conductibilities of these compounds are better, If there is a -M-X-M-X- or -M-M-M- (the distances between two atoms <0.31 nm) continuous electron transport path, and the electron configurations of the central metallic ion conform to the above condition, then the electric conductibilities are good, The isolate cluster can not become the continuous electron transport path, therefore, the formation of the isolate cluster will reduce the conductibility.

影响稀土复合氧化物电性的因素

合成了多种类型的稀土复合氧化物,研究它们的结构、电学性质.通过大量实验数据,总结了电子构型、自旋状态、电子输运通道与原子簇对稀土化合物电性影响的规律 中心离子的最外层电子轨道中若有未成对电子,并未呈半充满状态时,导电性好;化合物结构中必须具有原子间距小于0.31nm的—M—X—M—X—或—M—M—M—连续输运通道,且中心离子的电子构型符合上述导电性好的条件,化合物导电性好.孤立的原子簇不能成为导电通道,因此它的存在将减少导电性能.

(η~5-C_9H_7)_2Yb(THF)_2的晶体结构

双(茚基)镱(Ⅱ)四氢呋喃配合物(η~5-C_9H_7)_2Yb(THF)_2的晶体属单斜晶系,C_c空间群,晶体学参数a=13.506(4),b=11.081(2),c=15.577(5),β=92.68(3)°,V=2329(1),D_c=1.56g/cm~3,Z=4,μ=42.4cm~(-1),F(000)=1088,最终编离因子R=0.029,R_w=0.031。中心离子Yb~(2+)与两个茚基以η~5形式成键且与两个四氢呋喃中的氧成键,茚基的两个质心和四氢呋喃中的两个氧形成扭曲的四面体,Yb~(2+)在四面体的中心。Yb~(2+)的配位数为8。Yb~(2+)到质心In1的距离为2.52,到质心In2的距离为2.40。Yb~(2+)到O(1)的键长为2.356(7),到O(2)的键长为2.417(5)。

季铵盐类化合物在赤潮治理中的应用

有害赤潮的治理研究随着此灾害近年来日益加重而受到人们的广泛关注，并得到迅速发展；但直接控制藻花－－企图杀死或去除藻细胞或者削弱它们的毒性－－的研究实际上并没有取得实质上的突破。有机类杀藻剂是人们当前研究赤潮防治剂的热点之一。而季铵盐类化合物是一类价廉的工业产品。本文通过实验发现了季铵盐类化合物对赤潮异弯藻、中肋骨条藻等赤藻等赤潮藻有较的去除效果，在浓度为0.5mg/L，处理24h后对赤潮异变藻的去除率为85％。季铵盐的杀澡效率与其取代基有关，主要取代基碳原子数为12的去除效果好于碳原子数为18的；苄基的存在对其去除效果没有明显增效作用；含有一个长饱和脂肪烃取代基的季铵盐比含有两个长链的季按盐对藻的灭杀效果要高；盐中阴离子的不同对该类化合物对藻的灭杀作用没有影响。通过藻细胞体内叶绿素含量的变化，以及藻光合作用、呼吸作用的变化探讨了季铵盐类化合物去除赤潮生物的机理，实验结果表明该类化合物对赤潮藻的灭杀主要是通过表面活性吸附破坏藻的膜质结构，抑制叶绿体等细胞器的功能，导致藻的生长受到抑制，直至失去活性死亡。粘土类天然矿物絮凝剂是一类无化学危害的赤潮去除剂。为了提高粘土的去除率，我们研究了以季铵盐类化合物为改性试剂所得有机土的去除效果。结果表明；用少量季铵盐改性的有机土的去除效果在大于原土。用1.5CEC量的季铵盐改性得到的有机土，在1g/L用量下，对赤潮异弯藻去除率从原土的40％提高到100％。这主要是因为：一是改性后的粘土颗粒表面电荷为正，静电引力增大，絮凝作用增强；二是吸附在粘土表面的季铵盐类化合物，对粘土絮凝的赤潮生物仍灭杀作用，使藻的活性降低，有利于吸附去除。

One century record of contamination by polycyclic aromatic hydrocarbons and polychlorinated biphenyls in core sediments from the southern Yellow Sea

Sixteen polycyclic aromatic hydrocarbons (PAHs) and 28 polychlorinated biphenyls (PCBs) were measured at a 2-cm interval in a core sample from the middle of the southern Yellow Sea for elucidating their historical variations in inflow and sources. The chronology was obtained using the Pb-210 method. PAHs concentrations decreased generally with depth and two climax values occurred in 14-16 cm and 20-22 cm layers, demonstrating that the production and usage of PAHs might reach peaks in the periods of 1956-1962 and 1938-1944. The booming economy and the navy battles of the Second World War might explain why the higher levels were detected in the two layers. The result of principal component analysis (PCA) revealed that PAHs were primarily owing to the combustion product. Down-cored variation of PCB concentrations was complex. Higher concentrations besides the two peaks being the same as PAHs were detected from 4 to 8 cm, depositing from 1980 to 1992, which probably resulted from the disposal of the out-dated PCB-containing equipment. The average Cl percentage of PCBs detected was similar to that of the mixture of Aroclor 1254 and 1242, suggesting they might origin from the dielectrical and heat-transfer fluid. The total organic carbon (TOC) content played a prevalent role in the adsorption of high molecular weight PAHs (>= 4-ring), while no obvious relationship among total PCBs, the concentration of congeners, and TOC was found.

中国西部高山8种龙胆属植物的染色体数目

本文报道了我国西部高山上的8种龙胆属植物的染色体数目。其中宽街龙胆（Gentianaampla）的染色体数目为Zn＝48，提钟龙胆（G．stipitataSubsp．timensis）的染色体数目为2n=26）小齿龙胆（G．microdonta）和四数龙胆（G．lineolata）的染色体数目为2n=24，南山龙胆（G．grumil）的染色体数目为2n=18，上述5种植物的染色体数目为首次报道。其余蓝玉簪龙胆（G．veitchiorum）的染色体数目为2n=24，线叶龙胆（G．lawrenci Burk．var．farrei）的染色体数目为2n＝48，钻叶龙胆的染色体数目为2n＝18。