以DNA为模板构造苯胺-DNA复合物纳米线和聚苯胺纳米导线

在溶液中,以DNA为模板构造出了线性的苯胺-DNA复合物纳米线.用压缩气流将得到的复合物纳米线拉直并固定到云母基底上.用原子力显微镜(AFM)可观察到形貌规整的苯胺-DNA复合物纳米线.苯胺单体在溶液中能从各个方向上组装到DNA分子上,从而使DNA模板分子的表面包裹了一层苯胺.以苯胺-DNA复合物纳米线为前驱体通过进一步化学氧化聚合得到了以DNA为模板的聚苯胺纳米导线.

扫描探针显微镜在纳米加工中的应用

扫描探针显微镜不仅能对材料表面形貌进行原子级观测 ,还能够对单个的分子、原子及纳米粒子进行操纵。本文综述了扫描探针显微镜在纳米加工中对自组装单层膜的扫描探针刻蚀以及“蘸写笔”两方面的应用情况

Ultrathin multilayer films incorporating Keggin-type heteropolyanion clusters

Two new ultrathin multiplayer films have been successfully prepared fi-om Keggin-type heteropoly acids H-4[SiW12O40] and H-3[PMo12O40] with polyelectrolytes PEI, PSS, and PAH, using the electrostatic layer-by-layer self-assembly, technique. The XR results reveal their film thickness at nanoscale (similar to 20 nm). According to the AFM images, it is believed that the surface roughness (rough degree of film surface) of the polyelectrolyte-polyoxometalate film greatly depends on the kind of polyoxometalates.

Studies on electrostatic adsorption of proteins on modified surface by real-time surface plasmon resonance technique

The elucidation of key influence factors for electrostatic adsorption is very important to control protein nonspecific adsorption on modified surfaces. In this study, real-time surface plasmon resonance technique is used to characterize the electrostatic adsorption of two proteins (mouse IgG and protein A) on carboxymethyldextran-modified surface. The results show that protein solution pH and ionic strength are key influence factors for efficient electrostatic adsorption. The influence of protein, solution pH on the amount of electrostatic adsorption depends on the type of the charge and the charge density of both protein and modified matrix on the surface. The electrostatic adsorption process involves a competition between the positively charged protein and other positively charged species in the buffer solution. A decrease of ionic strength leads to an increasing electrostatic adsorption. The kinetic adsorption constants of protein A at different pH values were also calculated and compared.

ESR数据系统的研制

报道了电子自旋磁共振谱仪与ＩＢＭＰＣ微型机联用，建立了所需要的硬件系统，包括接口和放大器，研制了分辨率为１２位的ＡＤ／ＤＡ转换器，达到同步采样控制，并实现了Ｘ－Ｙ记录仪，示波器，绘图仪与打印机的输出，同时系统软件配有信号采样、信号累加、信号平滑、谱线加减、测量ｇ因子及Ａ值，ＥＳＲ谱的一、二次积分等一系列数据处理程序，还具有谱线模拟、线形分析等一些应用软件，对于谱的定量和解析极为方便，大大提高了谱仪的功能.

无线寻呼信息的计算机实时处理

在分析国际无线寻呼标准编码POCSAG(Post Office Code Standardization Adviso-ry Group)码的基础上,利用现有BB机的射频接收部分,以MCS-51单片微处理器为主体,设计了一个最小系统,实现对无线寻呼信号的射频解调、同步接收、通信纠错等处理,然后通过RS-232C标准串行接口传送到IBM-PC微型计算机中,进行信息译码,并在微机监视器上实时显示.

色散型光谱仪的通用计算机系统

通过微机技术与仪器改造技术相结合,探索了色散型光谱仪更新的新途径。以IBM微机为主系统,微机扫描控制器(MSC)为从系统,由RS-232串行通信口连接,以对话方式通讯、协议、交换信息。MSC的使用使系统具备了通用性和灵活性,在色散性光谱仪功能开发上具有广泛应用前景。该系统适用于红外、紫外、可见等色散型光谱仪。原机的测光系统与机械系统基本不变,由于增加了光谱数据处理能力,提高了光谱仪的使用性能。

AN EXPERT SYSTEM FOR SOLVENT-EXTRACTION OF RARE-EARTHS

An expert system for solvent extraction of rare earths has been developed using LISP. The goal of this project was to mimic the chemists' inferential abilities to assist in the process of solvent extraction of rare earths. The system includes frequently used extractants, separation of specific rare earths, recommendation of procedures for the separation of mixtures of rare earths using (2-ethylhexyl)phosphonic acid 2-ethylhexyl monoester, selection of parameters for counter-current extraction and methods for evaluation of the technique, and the economics of the processing. The expert system runs on an IBM-PC/XT.

Talc-bearing serpentinized peridotites from the southern Mariana forearc: implications for aseismic character within subduction zones

The serpentinized peridotites overlying the subducted zones in the Izu-Bonin-Mariana (IBM) arc system have been interpret as the cause of the low-velocity layer identified beneath the IBM froearc, in turn few earthquakes occurred along the plate boundary. Chrysotile, which is a low temperature and highly hydrated phase of serpentine with low frictional strength, has been suggested as the low velocity material in the serpentinized peridotites, besides, brucite is inferred to be likely conducive to stable sliding. However, such idea encounters challenging in our serpentinized peridotites from the southern Mariana forearc, which absent both the above minerals. The presence of talc, which characterized by its weak, low-friction and inherently stable sliding behavior, provides new clue. Here we report the occurrence of talc in serpentinized peridotites collected from the landward trench slope of the southern Mariana forearc. We infer that talc is mainly forming as a result of the reaction of serpentine minerals with silica-saturated fluids released from the subducting slab, and talc also occurs as talc veins sometimes. Due to its unique physical properties, talc may therefore play a significant role in aseismic slip in the IBM subduction zone.

Trace element composition of peridotites from the southern Mariana forearc: Insights into the geochemical effects of serpentinization and/or seafloor weathering

Peridotites from the southern Mariana forearc were sampled on the landward trench slope of the Izu-Bonin-Mariana (IBM) subduction zone by dredging. These mantle wedge peridotites underwent hydration by fluid derived from a dehydrated descending slab, and later interacted with seawater after emplacement at or near the seafloor. This study investigates how these two different rock-fluid interaction processes influenced trace element distribution in the southern Mariana forearc peridotites. We measured trace element concentrations of peridotites from the southern Mariana forearc. The southern Mariana forearc peridotites are characterized by a distinct seawater-like REE pattern with an obvious negative Ce anomaly, and La shows good correlation with other REEs (except Ce). In addition, there is a great enrichment of U, Pb, Sr and Li elements, which show a distinct positive anomaly relative to adjacent elements in the multi-element diagram. For the seawater-like REE pattern, we infer that REEs are mainly influenced by seawater during peridotite-seawater interactions after their emplacement at or near the seafloor, by serpentinization or by marine weathering. Furthermore, the anomalous behavior of Ce, compared with other rare earth elements in these samples, may indicate that they have undergone reactions involving Ce (IV) when the peridotites interacted with seawater. Positive U, Pb, Sr and Li anomalies are inferred to be related to seawater and/or fluids released during dehydration of the subducting slab.

琼脂分级产物的研究

琼脂（agar，又称琼胶）作为世界三大工业海藻胶之一，被广泛应用于食品、医药、生物技术、造纸等领域。本文首先研究了琼脂的分级方法，用DEAE-Cellulose将石花菜琼脂分级，得到四个级分，即水级分、0.5mol/L NaCl级分、1.0mol/L NaCl级分、2.5mol/L NaCl级分。分析了各级分的理化性质，并通过IR和~（13）C-NMR光谱研究其化学结构。石花菜琼脂分级得到的四个级分中，水级分的硫酸基含量为0.16%，凝胶强度为1130 g/cm~2（1%浓度），电内渗（EEO）为0.12，主要质量标准为Sigma公司的低电内渗琼脂糖(agarose）产品接近，符合低电内渗琼脂糖产品的质量要求。1.0mol/L NaCl级分和2.5mol/L NaCl级分的硫酸基含量较高，分别为22.8%和32.5%，合称为硫琼脂(agaropectin）。在琼脂糖的应用中，特别是现代生物技术研究中，需要低凝固温度琼脂糖。本文以石花菜琼脂分级得到的水级分为原料，采用甲基化反应制备低凝固温度琼脂糖。实验产品的凝固温度为30.1 ℃(1.5%浓度），融化温度为64.8 ℃（1.5%浓度），凝胶强度为264 g/cm~2(1%浓度），主要质量标准与Sigma公司的低凝固温度琼脂糖产品接近，符合低凝固温度琼脂糖产品的质量要求。随着对多糖生物学功能的深入，海藻硫酸多糖表现出多种生物活性，其活性研究已经成为目前新药研究的一个热点。到目前为止，有关琼脂分级产物的生物活性研究较少。本文在研究石菜硫琼脂的组成和主要理化特性的基础上，对基体内外抗凝血活性进行了较系统的研究。新西兰兔腹主动脉血体外抗凝实验结果表明，石花菜硫琼脂具有明显的体外抗凝血活性，在3.125mg/ml ～ 25mg/ml剂量范围内呈现量效关系；大鼠体内抗凝血实验的结果表明其口服可以吸收，在体内产生抗凝血作用，在100 mg/kg·d ～ 400 mg/kg·d剂量范围内，与全血凝血时间(CT）、凝血酶时间（TT）、凝血酶原时间（PT）、部分凝血活酶时间（KPTT）的延长及血浆纤维蛋白原（Fib）含量的降低均呈剂量依赖关系。就其抗凝血机制而言，石花菜硫琼脂的抗凝血作用既影响凝血系统，又影响纤溶系统。

基于GIS的黄河三角洲地面沉降研究及相关分析

黄河三角洲存在着不可忽视的地面沉降现象，并在一定程度上阻碍着三角洲的快速发展。对黄河三角洲地面沉降的研究在黄河三角洲防灾减灾、土地利用、河口河道治理等方面具有理论与实践指导意义。 本文收集了黄河三角洲地区1956年、1967年、1980年和1995年四个时期的1：5万地形图，提取高程信息，应用地理信息系统（GIS）软件生成数字高程模型并展开了相应的空间分析，得到各个时间段内黄河三角洲的地面沉降速率图，通过对各沉降速率图的统计分析得出了三角洲地区地面沉降的时空变化规律。文章继而分析了引发黄河三角洲地面沉降的三个主要诱导因子、它们在影响范围、作用时间、作用强度等方面的特点，以及在不同时间段内各诱导因子在引发地面沉降方面所发挥作用的主次。随后，在列举地面沉降对黄河三角洲产生的影响之后，归纳总结了防治地面沉降及其引发灾害的对策。最后，基于采用常规水准测量方法进行地面沉降监测费时费力，提出利用InSAR技术对黄河三角洲地面沉降进行监测的设想，并简要分析了其可行性。

Three dimensional fluorescence excitation-emission on matrix spectrum of dissolved organic substance in marine microalgaes growth process

The three-dimensional fluorescence spectrum was used to detect the changes in dissolved organic substances from the cultured Skeletonema costatum, Alexandrium tamarense, Alexandrium mimutum, Scrippsiella trochodea, Prorocentrum donghaiense and Prorocentrum micans. The result indicates that all of the microalgaes can produce FDOM in the growth courses. Diatom such as Skeletonema costatum can produce humic-like FDOM. However dinoflagellate can produce protein-like FDOM at exponential growth phase. When the algae grows into decadency phase, the intensity of humic-like and protein-like fluorescence augments rapidly, which may be due to a mass of FDOM realeased by the old or dead cell fragmentation and the degradation of bacteria by using non-FDOM. The fluorescent intensity of Alexandrium tamarense, Alexandrium mimutum, Prorocentrum donghaiense and Prorocentrum micans can reduce at anaphase of decadency phase because of the degradation of bacteria and light. The same genus of algae can produce similar FDOM, for example: Alexandrium tamarense, and Alexandrium mimutum, Prorocentrum donghaiense and Prorocentrum micans, but the positions of the fluorescence peaks are different.