CO adsorption on electrode of Pt nanoparticles investigated by cyclic voltammetry and <Emphasis Type="Italic">in situ</Emphasis> FTIR spectroscopy

Pt nanoparticles were prepared by the chemical reduction method.The average diameter of Pt nanoparticles was determined to be 2.5nm by TEM.The electrochemical propertis of Pt nanoparticles were studied by cyclic voltammetry,In comparison with massive Pt,the oxidation current peak of CO adsorbed on Pt nanoparticles in broader.Twin adsorbates of CO on Pt nanoparticles were determined by in situ FTIRS for the first time.It has revealed that the linear and twin-bonded CO can be converted into bridge-bonded CO with the variation of electrode potential.A series of special properties of Pt nanoparticles,such as enhanced IR absorption of CO adsorbates,were also observed.     

西北地区建立区域节水型社会经济体系的突破点

西北地区是我国水资源最为缺乏的地区，水资源短缺和利用不合理巳构成了我国西北地区区域经济可持续发展的主要障碍。本文通过对西北地区水资源总量及利用现状的分析与评价，指出西北地区经济可持续发展的关键是建立区域节水型社会经济体系，而其突破点在于严格控制垦荒，适度压缩灌溉农田面积，改变不合理的水资源利用结构，并对该突破点的意义进行了探讨。     

宋代风俗绘画管窥

宋代绘画是中国绘画艺术发展的高峰。宋代由于社会稳定、经济发达、城市繁荣导致市民阶层的壮大、市民意识的高涨和价值观念的转换,长期以来以宗教绘画创作为主和一贯关注贵族人物题材的画家开始自觉地关注市井题材,反映市民生活。风俗绘画除了延续辅助皇权“成教化、助人伦”的戒鉴作用外,更体现了庶族地主和城市平民的生活愿望,迎合世俗的欣赏口味和心理要求,以愉悦心目、平淡天真的观赏倾向和情趣为重,显示出独有的文化活力和艺术功能。在这样的背景下,宋代风俗画创作走向高潮。     

聚乙二醇(PEG)活化及其在药物释放和反应载体中的应用

本文综述了PEG羟基活化的方法，包括羟基转换为醛基、胺基、叠氮基、弄赢改酯基、羧基、烯基以及一些易离去基团如卤素、对甲苯磺改基等，并简述了其在药物释放和反应载体方面的应用研究最新进展。     

Receptive field plasticity of neurons in rat auditory cortex

Using conventional electrophysiological technique, we investigated the plasticity of the frequency receptive fields (RF) of auditory cortex (AC) neurons in rats. In the AC, when the frequency difference between conditioning stimulus frequency (CSF) and the best frequency (BF) was in the range of 1--4 kHz, the frequency RF of AC neurons shifted. The smaller the differences between CSF and BF, the higher the probability of the RF shift and the greater the degree of the RF shift. To some extent, the plasticity of RF was dependent on the duration of the session of conditioning stimulus (CS). When the frequency difference between CSF and BF was bigger, the duration of the CS session needed to induce the plasticity was longer. The recovery time course of the frequency RF showed opposite changes after CS cessation.The RF shift could be induced by the frequency that was either higher or lower than the control BF, demonstrating no clear directional preference. The frequency RF of some neurons showed bidirectional shift, and the RF of other neurons showed single directional shift. The results suggest that the frequency RF plasticity of AC neurons could be considered asan ideal model for studying plasticity mechanism. The present study also provides important evidence for further study of learning and memory in auditory system.     

两种在Visual C++环境下实现串行通信的方法

介绍了在Windows环境下的串行通信规约及串口操作,并提出两种在Visual C++环境下实现串行通信的方法一种是通过Windows API函数调用实现,另一种是结合Microsoft通信控件实现.分别用两种方法实现通信,并给出在Visual C++6.0环境下的程序框架.     

三叉神经慢性缩窄环术大鼠半月节射频热凝的实验研究

目的观察三叉神经慢性缩窄环术大鼠半月节射频热凝的大体及镜下改变,探讨射频热凝温度和时间与半月神经节损伤的关系。方法36只成年雄性SD大鼠,随机选取33只建立慢性缩窄性损伤三叉神经痛模型。建模成功2周后,随机分为3组：射频热凝组（R组,n=24）,假手术纽（S组,n=6）,热凝对照纽（C组,n=3）。经中颅窝开颅暴露半月神经节,R组行半月节穿刺热凝,根据温度、时间随机分为8个小组,每组3只,分别为：65℃120″、180″组,70℃120″、180″组,75℃120″、180″组,80℃120″、180″组。S组仅行半月节穿刺不热凝,按留针时间分为120″、180″两组;C组不行半月神经节穿刺及热凝。余3只SD大鼠作为正常对照组（N组）。R组及S组热凝或穿刺结束即取出大鼠半月神经节,C组、N组直接取出半月神经节,观察半月神经节大体变化,游标卡尺测量神经节毁损区直径,光镜下观察神经节细胞的变化。结果S组、C组与N组比较,大鼠半月神经节大体及光镜下均无明显变化。R组在65℃时大鼠半月节大体及镜下无明显损伤;70℃时开始在肉眼及镜下出现损伤;75℃、80℃时半月节则出现明显凝固区,毁损区直径测量较70℃组明显增大（P〈0．01）,光镜下神经元细胞核出现不同程度的固缩改变。毁损温度越高、时间越长,损伤范围越大,程度越重。结论75℃、80℃射频热凝可导致神经节细胞明显变性,损伤程度及范围随温度升高、时间延长逐渐加重与增大。     

厚朴酚与和厚朴酚清除DPPH·的作用

 采用DPPH·法,以芦丁为对照品,在无水乙醇和乙醇-水介质中对厚朴酚与和厚朴酚进行了自由基清除活性的初步研究.结果表明,厚朴酚与和厚朴酚都具有自由基清除活性.此外,初步探讨了其自由基清除活性反应机理.     

稻草栽培平菇培养基配方的研究

文中比较了自然发酵法、水煮处理法、牛粪处理法、石灰处理法对新鲜稻草的软化效果,并研究了用软化稻草和棉籽壳为主要原料,以玉米粉或大米为辅助材料的不同配方培养基的出菇情况。结果显示,稻草软化的最佳处理方式为石灰处理法;以软化后的稻草（占79%）、棉籽壳（占20%）、玉米粉或大米（占1%）配制的平菇培养基质能够很好的出菇,可以取得较好的经济效益。     

基于ISP技术的单片机与CPLD实验系统设计

在ISP技术的基础上设计了一个单片机与CPLD的综合实验系统。该系统具有很强的开放性,不仅可以提供基本的实验,而且还能方便地进行扩展。单片机软件的编写除了用C语言实现外,还提供了部分的汇编语言程序。