林道网综合评价的有向图模型

林道网规划是林业可持续发展中的一个重要问题，文中给出一个林道网综合评价的有向图模型，为林道网评价提供一种较为系统的方法。     

高电导率导电橡胶（LTDX型）的研制及应用

ＬＴＤＸ型高电导率电橡胶是由具有弹性的弹性体和优良导电性能的金属材料，经特种配方和加工方法制成的，主要用于波导平面法兰之间的垫片材料，它既导电又密封，使联接处有良好的电接触和气密性，而不使传输系统的驻波和插损变坏，同时减少能量泄漏，尤其是在高功能情况下能消除因法兰接触不良而引起的打火现象，提高了功率承受能力，是国内外正在研究的一种新的传输线联接技术。     

网点选择的聚类方法

本文介绍在网点选择问题中如何利用聚类分析方法，并且以宜昌市及巴东县为实例，给出这一区域的连锁网点     

随机Petri网同步并发行为的定量分析方法

传统的随机Ｐｅｔｒｉ网定量分析都是针对顺序行为的，而并发描述却是Ｐｅｔｒｉ网引以为骄傲的内容，这就形成Ｐｅｔｒｉ擅长描述并发，却没有在并发活动下分析系统的手段。本文研究同步并发机制下随机Ｐｅｔｒｉ网定量分析法，旨在改进传统的分析方法，使Ｐｅｔｒｉ网真正成为并发系统建模与分析的有力工具。     

磷和NaHSO3交互作用对温州蜜柑叶片光合作用的影响

经不同磷水平和8 mmol@L-1NaHSO3溶液处理后,不缺磷温州蜜柑的净光合速率(Pn)、最大荧光(Fm)、光化学效率(Fv/Fm)和电子传递速率(ETR)升高,光呼吸速率(Pr)及放O2活性无明显变化,Pr/Pn显著下降,缺磷温州蜜柑的Pn、Pr、Fm、Fv/Fm、ETR显著下降,Pr/Pn和放O2活性显著升高.无论缺磷与否,初始荧光(F0)变化不显著,O2-和H2O2的含量显著下降.认为喷洒8 mmol@L-1的HaHS03溶液有助于提高Pn,促进温州蜜柑进行光合作用.     

人工神经网络用于Ln3+的萃合及协萃体系稳定常数的关联和预测

研究了影响Ln^3 离子的萃合及协萃合物稳定性的有关因素。以Ln^3 离子的半径、电负性，4f电子排布周期因子q(本文自定义）以及基态L值等为参数，使用函数连接型神经网络（FLN），对Ln^3 的HTTA萃合物，HTTA－P350协萃合物及HTTA－TPB协萃合物的稳定常数分别进行了非线性关联和预测，获得了好的结果。     

Acid-base chemistry of montmorillonitic and beidellitic-montmorillonitic smectite

Suspension of a Tunisian purified smectite and American montmorillonite are studied by acid-base potentiometric and mass titrations. These experimental methods are used to determine the point of zero net proton charge (PZNPC). A very good agreement is observed between the two kinds of experiments. The two Namontmorillonites, studied at different ionic strengths, present proton adsorption vs. pH curves with a common crossing point. The PZNPC of the edge sites are 8.02 for Tunisian purified smectite and 8.11 for pure American montmorillonite. By analyzing the proton adsorption or desorption (H⁺ vs. pH) curves, one may assume the presence of four active sites at the surface. The montmorillonite surface undergoes two successive protonations and two successive deprotonations. Below pH < PZNPC and in acidic range, the cation exchange at layer sites and protonation of edge sites (>A1OH groups) occur simultaneously. For pH > PZNPC and in alkaline pH range, deprotonation of surface hydroxyl groups exposed at the edge sites (>SiOH, and >A1OH at high pH) of montmorillonite platelets causes an overall negative charge. Published in Russian in Elektrokhimiya, 2007, Vol. 43, No. 2, pp. 175–187. The text was submitted by the authors in English.     

In Situ Spectroscopic Analysis of Nanocluster Formation

The importance of small metal clusters in catalysis and the problems in understanding the clustering process in solution are outlined. A new analysis method for UV/Vis spectra is presented and applied to monitor the kinetics of ion reduction and cluster formation in situ. This method, which is based on a combination of two chemometric techniques, takes into account the entire UV/Vis spectrum and offers better interpretation possibilities than the traditional “band‐assignment” approach. This is particularly true for nanoclusters because these have significant spectral contributions also outside the broad plasmon band that is usually associated with them. The reduction of palladium, gold, and silver ions and the formation of the corresponding clusters is monitored in the presence of two different reducing agents, sodium borohydride and tetraoctylammonium acetate. While Pd²⁺ is found to reduce and cluster directly, the spectral decomposition of the Au³⁺ reduction profiles shows two species corresponding to the Au⁺ intermediate and the Au⁰ clusters. The rates of reduction and clustering for Pd, Au, and Ag are compared and the possibilities of synthesising multimetallic clusters of these metals by coreduction are discussed.     

A Three‐Dimensional Lead 2,6‐Dihydroxybenzoate with Channels

A lead 2,6‐dihydroxybenzoate of the formula Pb(C₁₄H₁₀O₈) ( I ) has been synthesized and characterized by X‐ray crystallography and spectroscopic techniques. (crystal data: monoclinic, space group = Cc (no. 9), a = 11.2155(2), b = 9.2942(2), c = 13.5112(3) Å, β = 96.510(1)°, V = 1399.31(5) ų, Z = 4). This is the first three‐dimensional metal dihydroxybenzoate structure, comprising 3,6‐connected periodic net and having channels with the dimensions 3.8 × 3.8Å and 10.8 × 3.8Å. The coordination of the PbO₈ polyhedron is holodirected and the electron lone pair of the lead is, therefore, not manifested in I . It exhibits photoluminescence in the violet, green and red when excited at 240, 390 and 525 nm, respectively.     

含S-P-N键的磷烯正离子及其相关物的结构和性质的从头计算

本文对5-甲硫基-3-N-苯基-2,3-2(H)-1,3,4,2-噻二唑磷茂啉的磷烯正离子等三个相关分子的平衡几何构型进行了从头算解析能量梯度方法的全优化计算. 优化结果表明, 二配位磷烯正离子与相应的三配位磷母体分子的结构有本质的差异.形成二配位磷烯正离子后,磷所在的五员环形成共轭体系而使原来的单键键长变短, 原来的双键键长变长, 且使原来不共面的五员环共面. 在优化的平衡几何处进行单点CI计算的结果表明, 基态分子中磷原子上的正电荷的相对多少次序与实验测得的摩尔电导率及^3^1P NMR谱的化学位移的相对大小次序完全一致.