Morphological study on water-borne conducting polyaniline-poly(ethylene oxide) blends

Conducting polyaniline-poly(ethylene oxide) blends were prepared from their aqueous solutions. The blends displayed an electrical conductivity percolation threshold as low as 1.83 wt % of polyaniline loading. As demonstrated by scanning electron microscopy, polarized optical microscopy, and wide-angle X-ray diffraction studies, the conducting polyaniline took a fibrillar morphology in the blend, and it existed only in the amorphous phase of poly(ethylene oxide). A three-phase model combining morphological factors instead of a two-phase model was proposed to explain the low-conductivity percolation threshold.

Electrochemical behavior and electrocatalytic properties of ultrathin films containing silicotungstic heteropolyanion SiW12O404-

We describe here a controlled fabrication of ultrathin monolayer and multilayer films consisting of silicotungstic heteropolyanion SiW12O404- and a cationic polymer of quaternized poly(4-vinylpyridine) partially complexed with osmium bis(2,2'-bipyridine) on Au electrodes previously self-assembled with cysteamine monolayers based on layer-by-layer electrostatic interaction. The thus-forming monolayer and multilayer chemically modified electrodes are investigated by cyclic voltammetry on their electrochemical behavior and electrocatalytic properties. The composite ultrathin films exhibit remarkable electrocatalytic effects on the reduction of BrO3-, H2O2, and HNO2. The electrocatalytic effects on HNO2 reduction are enhanced with increasing layer number from 1 to 3 but level off with much thicker multilayers. The stability of the monolayer and multilayer films is also examined. (C) 2000 The Electrochemical Society. S0013-4651(99)04-057-4. All rights reserved.

A nickel molybdenum phosphate with tunnel: Hydrothermal synthesis and structure of (NH3CH2CH2NH3)(4)center dot(NH3CH2CH2NH2)center dot Na center dot[Ni2Mo12O30(PO4)(HPO4)(4)(H2PO4)(3)]center dot 6H(2)O

A nickel molybdenum phosphate, (NH3CH2CH2NH3)(4).(NH3CH2CH2NH2). Na .[Ni2Mo12O30(PO4)(HPO4)(4)(H2PO4)(3)]. 6H(2)O, invoicing molybdenum present in V oxidation, has been hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction. Deep brown-red crystals are formed in the triclinic system, space group P (1) over bar, a = 12,011(2), b = 14,612(3), c = 21.252(4) Angstrom, alpha = 80.54(2)degrees, beta = 83.10(2)degrees, gamma = 76.29(2)degrees, V = 3561.4(12) Angstrom(3), Z = 2, lambda(MoK alpha) = 0.71073 Angstrom (R(F) = 0.0529 for 9880 reflections), Data mere collected on a Siemens P4 diffractometer at 20 degrees C in the range of 1.75 degrees < theta < 23.02 degrees using the omega-scan technique. The structure was solved by direct methods using the program SHELXTL-93 and refined with the method of fun-matrix least-squares on F-2. The structure of the title compound may be considered to be two [Mo6O15(HPO4)(H2PO4)(3)](5-) units bonded together with a nickel atom, although several P-O groups are not protonated on account of coordination with a Na+ cation, The one-dimensional tunnels were formed in the solid of the title compound. A probe reaction of the oxidation of acetaldehyde with H2O2 using the title compound as catalyst was carried out in a liquid- solid system, showing that the title compound had high catalytic activity in the reaction, (C) 1999 Academic Press.

LB膜修饰电极

本文对 LB 膜修饰电极特点、电化学行为及其在光电化学,电催化,传感器等方面的应用进行了综述。

A NEW KIND OF ION-SELECTIVE ELECTRODE BASED ON CONDUCTING POLYMER FILM

Organic conducting polymers have attracted much interest in material science. This letter reports potentiometric response behavior of polypyrrole (PPy)polymer film electrodes prepared by electrochemical polymerization, and a new kind of ion selective

两步激发激光增强电离光谱分析——半导体硅中钠的测定

本工作做了方法原理性实验,给出两步与一步激发激光增强电离(LEI)光谱相比较的钠的标准曲线、检出限以及在不同钠浓度下的相对标准偏差。并将该技术应用到实际样品半导体硅中钠的测定。标准加入回收率在82～125％范围之内。实验证明该技术对实际样品分析是可行的。

Ho~(3+)离子及HoP_5O_(14)晶体的光谱性质

根据HoP_5O_(14)的吸收光谱和荧光光谱,用Judd-Ofelt理论计算了Ho~(3+)的强度参数.并计算了激发能级的辐射跃迁速率、辐射寿命、荧光分支比和积分发射截面等光谱参数.

通过等离子体表面处理提高聚乙炔稳定性

用等离子体方法对聚乙炔膜进行表面处理发现,其碘掺杂室温电导率与未处理的PA膜相当,但电导在空气中的稳定性及膜自身的抗氧化能力都有了较大提高。ESCA谱证实了在空气等离子体处理后的PA膜表面上接入了O和N原子。另外,IR光谱结果也表明,随着等离子体处理功率的增加,PA膜反式食量逐渐增加,顺式含量相应减少。

Numerical modeling of water wave interaction with a soft mud bed

A vertical 2-D numerical model is presented for simulating the interaction between water waves and a soft mud bed. Taking into account nonlinear rheology, a semi-empirical rheological model is applied to this water-mud model, reflecting the combined visco-elasto-plastic properties of soft mud under such oscillatory external forces as water waves. In order to increase the resolution of the flow in the neighborhood of both sides of the inter-surface, a logarithmic grid in the vertical direction is employed for numerical treatment. Model verifications are given through comparisons between the calculated and the measured mud mass transport velocities as well as wave height changes.

南海新生代碱性玄武岩的特征及其地球动力学意义

南海是西太平洋最大的边缘海之一，位于欧亚板块、印-澳板块以及太平洋板块之间。南海海底扩张停止(15.5Ma, Briais et al., 1993) 后的板内火山作用，影响着中国南部、中南半岛、大洋基底和分裂的微大陆片段的广大地区。对南海新生代玄武岩进行地球化学研究，不仅对于理解南海板内火山作用的深部地幔过程有着重要意义，而且对南海形成演化及含油气盆地形成的深部动力学机制有着深远意义。 南海新生代玄武岩K-Ar/Ar-Ar年龄为3.8-7.9Ma, 表明为晚中新世以来的岩浆活动产物，与周边地区的碱性火山岩在年龄上的一致性。岩石学特征表明，南海新生代玄武岩的矿物组合为橄榄石、单斜辉石、斜长石，与特征的碱性玄武岩的矿物组合一致。由橄榄石所计算的南海底潜在地幔温度(Tp)平均值为1661℃, 暗示南海地区下的地幔可能存在热量异常，为海南地区存在地幔柱的观点提供了证据。单斜辉石富钙、钛，由单斜辉石-熔体平衡温压计计算的岩浆房深度分别为：碱玄岩岩浆房深度约49km（对应压力为1.46～1.48 GPa）；粗面玄武岩岩浆房约25km（对应压力为0.76 GPa）；玄武岩岩浆房约15km（对应压力为0.44GPa）。由碱玄岩→粗面玄武岩→玄武岩，平衡温度(K)依次降低:从1535～1498→1429→1369。由斜长石微晶所计算的岩浆喷出地表的温度为989℃。 主量元素特征表明，岩石类型主要为碱玄岩，有少量的粗面玄武岩和玄武岩，属于碱性系列。微量元素方面，大离子亲石元素(LILE)以及高场强元素（HFSE）特别是Nb、Ta、Ti、Y等元素均呈现富集现象，Yb、Sc、Sr以及K、U、Th等生热元素相对亏损，微量元素及稀土元素分布岩石类似板内OIB微量元素的全球平均值。同位素地球化学研究表明，源区存在两个混合端员并具Dupal Pb异常：一个为DMM，位于软流圈或岩石圈地幔中；另一个为EM2源区，可能来自位于核-幔边界处的海南地幔柱而非大陆底岩石圈地幔。研究表明，南半球Dupal异常不存在全球范围内的地区专属性，本区存在的Dupal异常与南半球Dupal异常可能不存在联系。在南海新生代玄武岩的成因过程中，海南地幔柱在为岩石圈地幔的部分熔融作用提供所需的热量同时，也在物质上作出了贡献。南海盆新生代碱性玄武岩由不同程度的部分熔融作用，以及岩浆在上升期间或者在高位岩浆房中的橄榄石等矿物分离结晶作用所形成，同时还可能发生了堆晶作用。构造环境判别表明，玄武岩浆在上升到地表过程中几乎未受到地壳混染。 南海新生代玄武岩的地球化学研究表明，在玄武质岩浆的深部地幔演化过程中，海南地幔柱可能起着重要的作用。通过引入海南岛地幔柱这个概念，本文建立了一个新的有关南海形成演化的初步的概念性模型：（1）50-32Ma，印度洋板块-欧亚板块碰撞及其所导致的太平洋板块后退的综合效应为南海地区提供了一个伸展环境，此伸展环境为地幔柱物质的上升提供了通道；（2）32-21Ma，当地幔柱柱头到达软流圈时, 通过侧向物质流开始同扩张中心发生相互作用，促进了南海的扩张，并在26-24Ma期间发生了洋脊重新就位事件，使扩张中心从原来的18°N附近(即现今西北海盆的中心)调整到15.5°N附近（即现今的东部亚盆）；（3）21-15.5Ma, 随着地幔柱效应的逐渐增强，热点-洋脊相互作用越来越强烈，在大约21Ma发生了洋脊的再次重新就位事件，诱发了西南海盆的扩张；（4）15.5-现在，由于印澳板块前缘与巽他大陆碰撞，使得南海大约在15.5Ma停止扩张,并沿着南沙海槽及吕宋海沟向菲律宾岛弧及巴拉望地块之下俯冲，而南海热点继续活动，在地表处直到第四纪还有碱性玄武岩喷出。

Sustained response to selection in an introduced population of the hermaphroditic bay scallop Argopecten irradians irradians Lamarck (1819)

Introduced species often start with limited genetic variability, which is problematic for selective breeding. The problem of inbreeding can be exasperated by hermaphroditism. The bay scallop Argopecten irradians irradians is a hermaphroditic species that has been introduced to and now supports a major aquaculture industry in China. Positive response to selection for fast growth was observed in one of the less inbred stocks in a previous study. In this study, we evaluated selection for the second generation to determine if response to selection can be sustained in this introduced population of a hermaphroditic species. Response to selection, realized heritability for the second generation, cumulative (over two generations), current (for the second generation) and residual (from the first generation) genetic gains were estimated by comparing three different types of lines: SS (selected for two generation), SC (selected for the first generation only) and CC (unselected for two generations). The SS line grew significantly faster (P < 0.05) than the other two lines, indicating that the second generation selection for faster growth is still effective. Response to selection and realized heritability for the second generation were 0.612 +/- 0.101 and 0.349 +/- 0.057, respectively, which are similar to those observed for the first generation. The cumulative, current, and residual gains were 17.56 +/- 5.30%, 10.63 +/- 2.46%, and 6.25 +/- 3.13%, respectively. The sustained response to selection for the second generation observed here suggests that considerable genetic variability exists in this population and that future efforts on selective breeding are likely to be fruitful. (c) 2005 Elsevier B.V. All rights reserved.

角百灵和小云雀的巢址选择与竞争共存

于2000---2002年的鸟类繁殖期在中国科学院海北高寒草甸生态系统定位站，测定了27窝角百灵(Eremophtla alpestns)和43窝小云雀(Alauda gulgula)的巢址特征，观察了两者在繁殖期巢数的季节变化，并运用稳定性同位素技术测定了育雏食物，对两种百灵的巢址特征和食物重叠度进行了比较。结果表明两者的巢址特征存在着显著的不同：角百灵的巢开放度为92．16％，小云雀的为34．61％，前者的巢开放度显著大于后者(P<0．01)；角百灵距巢100 em范围内遮蔽物的数量为0．070．26，小云雀的为2．571．19，前者显著少于后者(P<0．01)；角百灵巢址植被的高度和盖度也显著小于小云雀的(P<0．01)。角百灵和小云雀均以小型昆虫育雏，育雏食物的资源重叠程度很高，为O．8957；而且两者的繁殖季节和繁殖强度也是相互重叠的。这两种百灵鸟类在巢址的选择上存在着一种代价和利益的权衡关系，巢址选择是捕食压和热条件共同作用的结果。二者共存的机制是巢址上的分化。

捕杀对高原鼢鼠种群年龄结构及繁殖的影响

捕杀高原鼢鼠后, 残鼠种群与自然种群年龄结构相比较, 5 月差异性显著( X2 =9197 , P < 0.05) ; 7 月和10月差异极显著( X2 = 15.134 , X2 = 15.612 , P < 0.01) 。5 月, 残鼠种群成年Ⅰ组占最大比例(53.45 %) ; 自然种群成年Ⅱ组占最大比例(48.44 %) 。7 月,残鼠种群幼年组和亚成年组所占比例之和( 35.06 %) 明显高于自然种群( 22.00 %) ( P <0.05) 。10 月, 残鼠种群近老年组和老年组所占比例之和( 9.62 %) 明显低于自然种群(23.08 %) ( P < 0.05) 。残鼠种群成年Ⅰ组雌鼠怀孕率( 84.62 %) 明显高于自然种群(58.33 %) ( P < 0.05) ; 平均胎仔数(3.32) 也高于自然种群(2.85) , 但差异不显著( P >0.05) 。

预编程自治水下机器人控制问题研究

本文简要地介绍了“CR-01” 6000 米自治水下机器人控制系统的构成，同时介绍了其控制系统核心：自动驾驶系统和机载设备控制系统及相应计算机系统的硬件结构。对“CR-01”控制系统软件，主要是自动驾驶系统、机载设备控制系统的软件及自动驾驶系统程序的内核-实时监控程序作了进一步的剖析。此外，还着重介绍了该机器人的使命编程语言和应急系统软件。本文深入研究了“CR-01”的航行控制系统。“CR-01”主要有两种运动控制方式：机器人作业时的控制方式和机器人悬浮时的控制方式。分别介绍了在这两种不同的控制方式下，机器人各控制回路的结构以及力矩平衡方程。本文简要介绍了滑模控制理论，并根据水下机器人的空间运动方程建立了“CR-01”的数学模型，将滑模控制算法应用到“CR-01”水平航向控制回路中。通过METLAB软件中的一些仿真方法，对“CR-01”PID控制算法和滑模控制算法分别进行了仿真研究。在仿真研究的基础上，成功地进行了“CR-01”水平航向控制回路PID控制算法和滑模控制算法的试验，试验是在沈阳自动化所的水下实验室的水池中进行的。其中滑模试验是本文的重点，主要试验包括：基础试验、选取不同滑动面进行试验、滑动面的平滑试验、控制算法的改进试验和控制算法的优化试验。一系列的试验结果证明：滑模控制算法是一种适合水下机器人的控制算法，使用滑模控制算法使”CR-01“控制系统的性能有所提高，同时增强了系统的鲁棒性。