La1-x-y-zCexPryNdzB5电极材料组成的优化与设计

利用正交设计方法对ＡＢ５型混合稀土镍系合金电极材料Ｌａ１－ｘ－ｙ－ｚＣｅｘＰｒｙＮｄｚＢ５的容量、高倍率放电性能、循环寿命和电压平台等性能进行了实验测定，以进一步优化电极材料的Ａ组元，提高电极性能。通过模式识别对实验数据进行分类并据此设计了新的样本。利用人工神经网络方法对新样本的电性能进行了预报，结果与实验值基本一致，新设计的样本点具有比较好的电性能。     

人工神经网络用于高效液相色谱分析条件的优化

本文采用人工神经网络的线性网络法（ＬＭＳ）优化高效液相色谱的分析条件，考察了样本集类型和不同初始权值对优化结果的影响。结果表明，模拟的精度与样本集类型有关，而在一定置信区间与初始权值无关。     

贮氢材料电极循环寿命的定量预测定时放电半衰期法的应用

贮氢材料电极循环寿命的定量预测定时放电半衰期法的应用韩剑文，袁满雪，周作祥，赖城明（南开大学化学系天津３０００７１）关键词：贮氢电极，循环寿命，半衰期。前文￣［１］讨论了应用定终点电位放电半衰期法来预测贮氢材料电极循环寿命的问题。本文讨论如何采用定时...     

贮氢材料电极循环寿命的定量预测（Ⅰ）─—定终点电位放电半衰期法的应用

贮氢材料电极循环寿命的定量预测（Ⅰ）─—定终点电位放电半衰期法的应用韩剑文，袁满雪，周作祥，赖城明（南开大学化学系３０００７１）关键词：贮氢电极，循环寿命，半衰期目前所应用的贮氢材料电极，一般都具有较高的比容量和较长的使用寿命。因而很需要一种能够定量...     

芳胺化合物光催化降解过程中的反向传播人工神经网络光度法同时测定

利用芳胺的重氮化偶合反应，采用误差反向传播人工神经网络方法，对于吸收重叠的3组分芳胺类化合物体系进行同时测定；并用该法测定了以高压紫外汞灯为光源，纳米金红石相TiO2为催化剂，光催化降解苯胺、甲萘胺、邻氯苯胺3组分过程中各组分浓度；实验证明对合成样本与催化体系样本，回收率均在91％－108％之间，其结果准确可靠。     

红外指纹图谱和聚类分析法在赤芍产域分类鉴别中的应用

以赤芍的红外指纹图谱为依据，采用主成分分析法对来自18个产地的赤芍进行了聚类分析。可将18个产地大致分为6类，这一分类与地理位置有较明显的对应关系，同一区域内赤芍的性能较为相似，可作为传统中医界对赤芍药材质量评价的依据。用径向基函数人工神经网络法预测了45个赤芍样本的产区，结果表明，径向基函数人工神经网络法具有较强的预测能力，用它可鉴别赤芍的产区。可为药材的质量控制提供一个快捷、准确、可行的鉴别方法。     

锂离子电池用非晶硅薄膜负极材料的研究

采用磁控溅射法在铜箔集流体上沉积得到了厚度约2 μm的非晶硅薄膜。X-射线衍射(XRD)、高分辨率透射电镜(HRTEM)和选区电子衍射(SAED)分析表明，该薄膜为非晶态。扫描电镜(SEM)结果表明，该硅电极在电化学吸、放锂循环后体积膨胀率为300%，但电池依然保持良好的循环寿命。在1.5～0.005 V (vs Li⁺/Li)和0.1 mA·cm^-2条件下，该薄膜电极循环100 次后容量仍能保持在0.47 mAh·cm^-2以上，为初始容量的84%。每周容量衰减率仅为初周的0.16%。HRTEM和SAED结果表明，该薄膜在电化学吸、放锂循环后仍为非晶态，这可能是其具有良好电化学循环寿命的主要原因。     

人工神经网络方法用于肺癌的辅助诊断

根据人发和血清中微量元素的含量,将人工神经网络(ANN)用于正常人与癌症患者的分类预测.用独立预测样本作了检验,表明该方法可作为肺癌诊断的一种辅助手段.讨论了当预测样本中有元素缺损时ANN的分类预测情况,并研究了人发和血清样品中的元素对分类预测的影响.     

人工神经网络紫外吸收光谱法测定安钠咖注射液各组分

应用人工神经网络原理，采用误差反向传播方法，对紫外吸收光谱重叠的安钠咖注射液中咖啡因和苯甲酸钠含量进行测定．实验表明，人工神经网络法对上述两组分含量测定结果准确，探讨了人工神经网络参数对分析结果的影响．     

碳纳米管复合导电剂的应用研究

锂离子电池及其相关技术的发展对容量、充放电倍率特性、循环寿命和加工适用性等提出了更高的要求。目前最常用的负极和正极材料与电解液相容性差，充放电过程中结构变化大易剥落导致电池循环稳定性差。鉴于碳纳米管大的长径比、良好的导电性能、优异的力学性能和化学惰性，很适于用作导电剂提升电池性能。本文主要研究了碳纳米管复合材料用作导电剂，并制作成品锂离子电池检测其性能。主要取得了两项实用成果：（1）获得碳纳米管复合导电剂的制备方法，而且采用简单的机械搅拌就可以将复合导电剂进行有效均匀分散，易于进行规模化应用；（2）用碳纳米管复合材料作导电剂，与目前常用的导电剂导电碳黑相比，锂离子电池循环寿命提高一倍以上。     

New Q membrane scale-down model for process-scale antibody purification

Process-scale antibody production requires polishing steps with extremely high product throughput and robust operation. In this communication, the Sartobind Q membrane adsorber for process-scale antibody production is evaluated as an alternative to Q column chromatography. Although the capacity seen with large-scale membrane adsorbers is competitive with column chromatography, the same throughput is not achieved with the current scale-down models. The operational issues currently found in membrane scale-down models, including backpressure, which significantly compromises the membrane's capacity, were examined. A new scale-down model was designed to mimic the liquid flow path found in the large-scale capsule, and a new process capacity equivalent at both small and large scale was successfully achieved. Results of a 4-model virus study with a redesigned Sartobind Q absorber scale-down model at the new process capacity are presented.     

Distribution threshold values of CaCl_2 onto the 10X-zeolite and macro-pore silica gel

The calcium chloride used for adsorption separation of ammonia is promising for its large adsorptive capacity and lower desorption temperature,but difficult to develop because of the liable expansion,lump and chip in the adsorption/desorption process.Composite adsorbents made by monolayer dis-persion of calcium chloride onto carriers with high surface areas exhibit better adsorptive capacity and stability.Several models were developed to confirm the maximum monolayer dispersion capacity of calcium chloride ...     

Feasibility study for the use of near infrared spectroscopy in the qualitative and quantitative analysis of green tea, Camellia sinensis (L.)

This paper indicates the possibility to use near infrared spectroscopy (NIR) combined with PLS as a rapid method to estimate the quality of green tea. NIR is used to build calibration models to predict the content of caffeine, epigallocatechin gallate (EGCG) and epicatechin (EC) and for the prediction of the total antioxidant capacity of green tea. For the determination of the total antioxidant capacity, the trolox equivalent antioxidant capacity (TEAC) method is used. Until now, the prediction of the antioxidant capacity as such by use of NIR has not been reported. For caffeine and TEAC, models are build for the whole green tea leaves and also for the ground leaves. For the polyphenols (EGCG and EC), only models for the whole leaves are investigated. A partial least squares (PLS) algorithm is used to perform the calibration. To decide upon the number of PLS factors included in the PLS model, the model with the lowest root mean square error of cross-validation (RMSECV) for the training set is chosen. The correlation coefficient (r) between the predicted and the reference results for the test set is used as an evaluation parameter for the models: for the TEAC results r=0.90 for the model with the whole leaves, r=0.86 for the model with the powdered leaves are obtained. The caffeine prediction model has a correlation coefficient r=0.96 for the whole leaves and r=0.93 for the ground leaves. The correlation coefficient for the EGCG and the EC content models are, respectively 0.83 and 0.44.     

空气源热泵空调器制热量测量不确定度评定

分析并筛选了空气焓值法测量制热量测定不确定度的主要来源,通过数学模型进行不确定度的A类评定和B类分析,推导和建立了静压差、焓值、空气比容、空气湿度等制热量不确定度主要分量的数学模型,通过实验数据评定了制热量不确定度。采用极限取值评定复杂不确定度分量,为制热量不确定度评定提供了一种简便可靠的方式。     

Heat capacity effects associated with the hydrophobic hydration and interaction of simple solutes: a detailed structural and energetical analysis based on molecular dynamics simulations

We examine the SPCE [H. J. C. Berendsen et al., J. Chem. Phys. 91, 6269 (1987)] and TIP5P [M. W. Mahoney and W. L. Jorgensen, J. Chem. Phys 112, 8910 (2000)] water models using a temperature series of molecular-dynamics simulations in order to study heat-capacity effects associated with the hydrophobic hydration and interaction of xenon particles. The temperature interval between 275 and 375 K along the 0.1-MPa isobar is studied. For all investigated models and state points we calculate the excess chemical potential for xenon employing the Widom particle insertion technique. The solvation enthalpy and excess heat capacity is obtained from the temperature dependence of the chemical potentials and, alternatively, directly by Ewald summation, as well as a reaction field based method. All three methods provide consistent results. In addition, the reaction field technique allows a separation of the solvation enthalpy into solute/solvent and solvent/solvent parts. We find that the solvent/solvent contribution to the excess heat capacity is dominating, being about one order of magnitude larger than the solute/solvent part. This observation is attributed to the enlarged heat capacity of the water molecules in the hydration shell. A detailed spatial analysis of the heat capacity of the water molecules around a pair of xenon particles at different separations reveals that even more enhanced heat capacity of the water located in the bisector plane between two adjacent xenon atoms is responsible for the maximum of the heat capacity found for the desolvation barrier distance, recently reported by Shimizu and Chan [J. Am. Chem. Soc. 123, 2083 (2001)]. The about 60% enlarged heat capacity of water in the concave part of the joint xenon-xenon hydration shell is the result of a counterplay of strengthened hydrogen bonds and an enhanced breaking of hydrogen bonds with increasing temperature. Differences between the two models with respect to the heat capacity in the xenon-xenon contact state are attributed to the different water model bulk heat capacities, and to the different spatial extension of the structure effect introduced by the hydrophobic particles. Similarities between the different states of water in the joint xenon-xenon hydration shell and the properties of stretched water are discussed.     

Remediation of lead by pretreated red algae: adsorption isotherm,kinetic, column modeling and simulation studies

Batch and column biosorption experiments were carried on for lead uptake using ecofriendly biosorbents (raw and calcium chloride [CaCl₂] or formaldehyde pretreated form of red marine algae Jania ruben [Linnaeus]). The best-fit (linear and nonlinear) isotherms, kinetics, and column adsorption models were identified using statistical analysis. Freundlich, Langmuir, Temkin, Redlich–Peterson, and Elovich adsorption isotherm models were tested. Highest adsorption capacity (774 mg/g) has been observed with Jania algae pretreated with formaldehyde. Pseudo-first- and second-order adsorption kinetics were applicable. The column capacity for lead removal with Jania pretreated with CaCl₂ was found to be 1089.6 (mg/g) from the breakthrough curve area method. Thomas, Yoon-Nelson, Yan, and Clark column models were tested with regression analysis. Thomas model is the best column model with capacity q_Th = 1092.4 mg/g. Overall, 98.5% regeneration of column was achieved, indicating the suitability of using algae materials in multioperational cycles. Adsorbed lead present in algae material was confirmed by thermal analysis.     

Magnetostructural study of 2-(4-N-tert-butylaminoxylphenyl)benzimidazole

The heat capacity of the title organic free radical, PhBABI, was measured over 0.3-300 K by adiabatic calorimetry and relaxation methods in the presence of external magnetic fields up to 9 T. A hump in the magnetic heat capacity was observed with a maximum at about 15 K in zero field, which did not shift at fields up to 9 T. The experimental magnetic entropy was in good agreement with the theoretical value of R ln 2 (= 5.76 J K(-1) mol(-1)) for S = 1/2 systems. The higher temperature, field-insensitive feature was fitted to several antiferromagnetic Heisenberg models. The best fits were obtained using spin ladder and coupled spin bilayer models.     

针铁矿对焦磷酸根的吸附特征及吸附机制

为深入了解自然水体中焦磷酸盐的迁移转化行为,以表生环境中广泛存在的稳定矿物-针铁矿为研究对象,系统研究了其对焦磷酸根的吸附过程,探索了不同实验条件下(pH值、电解质、时间、温度)针铁矿对焦磷酸根吸附的影响。 结果表明,溶液pH值从6.27升至10.99时,总磷吸附量从3.00 mg/g降低至0.75 mg/g;电解质浓度越低越有利于针铁矿对焦磷酸根的吸附;吸附剂对焦磷酸根的吸附量在最初1 h内增长较快,随后渐渐达到吸附平衡;溶液温度的升高对吸附量提高具有增强作用。 用动力学和热力学模型对吸附过程进行拟合,发现准二级动力学和Langmuir模型具有更好的适用性。 结合材料吸附焦磷酸根前后的表征,推导出针铁矿对焦磷酸根的吸附机制可能是以表面配合和物理吸附为主导。     

Modeling of the heat processing of continuously molded product

The mathematical models of heat processing (heating and cooling) of materials, semi-products and products, including multilayer produced by continuous molding, in particular, by extrusion and calendering are considered. The proposed models allows selection of main sizes of devices of the heat processing line for a preset output or determination of a maximum capacity of the line for given sizes of these devices.