Photovoltaic Properties and Quantum Size Effect in Nanocrystalline CeO2

Different size. nanocrystallines CeO2 were synthesized and their diffuse reflectance absorption spectra have heen measured. The absorption band in the region from 300 to 450 nm was assigned to the O2p-Ce2 4f transition. It was found that a strongly red-shifted broad continuum of the absorption band occured as the decrease of the partical size. We have also measured the surface photovoltage as function of wavelength by SPS technique. And the absorption band was resolved to two peaks with different photovoltaic properties. Photovoltaic quantum size effect was observed by FMSPS measurement.

ANALYSIS OF ANGULAR OVERLAP PARAMETERS FOR THE LAOXEU3+ (X = CL, BR, I) SERIES

The Angular Overlap Model (AOM) is applied to the LaOX:Eu3+(X = Cl, Br, I) series involving sigma, pi, delta and phi effects based on the experimental energy levels. The calculations are made in two cases. (1) Consider oxygen and halogen having the same bond-length. (2) Consider the real structure. In both cases, the results show that for sigma-bonding parameters, the values of e(sigma) decrease with increasing charge number of halogen, i.e. Cl- > Br- > I-, this indicates that the bonding ability also decreases with this order. The absolute values of each parameter are much larger than zero-therefore they all must be included in a practical analysis. In the second case, the values of the e(pi) parameter are negative, which means a ''back-bonding'' is formed, and this is profitable for the formation of sigma-bonding, usually referred to as ''synergic effect''.

共混高聚物阻尼材料

随着现代化技术的迅速发展,飞机、导弹和卫星等系统的减振隔音问题成为迫待解决的问题。由于这些系统的功率和速度的极大提高,引起强烈的宽频带随机振动和噪音,而且由于结构和仪器又是多自由度系统,因此,这种宽频振源将会激发起结构和仪器的许多共振峰,使结构破坏、仪器失灵。据了解火箭导弹系统的宽频带随机振动频率通常在20～2000Hz范围,最大加速度可达70～80g。

乙烯-α-烯烃共聚物序列结构的~(13)C NMR研究——Ⅳ.氯化聚乙烯(CPE)

本文应用取代基效应方法研究了氯化聚乙烯~(13)C NMR谱的归属。讨论了它的链结构并指出中氯含量氯化聚乙烯的结构特征是分子链中出现1,2-二氯乙烷式的结构,从氯化聚乙烯的~(13)C谱中归纳出取代基参数,发现氯含量和温度的改变对取代基参数没有明显的影响。而在溶剂ODCB中加入C_2Cl_4后,取代基参数S_1减小0.48ppm。文章最后研究了氯化聚乙烯的序列分布,讨论了氯含量对序列结构的影响。

Expression, purification, and characterization of recombinant Chinese shrimp crustin-like protein (CruFc) in Pichia pastoris

A crustin-like protein (CruFc) from Fenneropenaeus chinensis was expressed in Pichia pastoris and then purified to electrophoretic homogeneity on a Sephacryl S-100 column with a band corresponding to the expected one (13 kDa) shown by 15% SDS-PAGE. Western blot indicated that the rCruFc specifically reacted with polyclonal rabbit anti-Fenneropenaeus chinensis CruFc. Production in a 5 l bioreactor gave 237 mg rCruFc/l. Antimicrobial assay revealed that 4 mu M rCruFc inhibited growth of Staphylococcus aureus.

Seismic characteristics of a reef carbonate reservoir and implications for hydrocarbon exploration in deepwater of the Qiongdongnan Basin, northern South China Sea

Our analysis of approximately 40,000 km of multichannel 2-D seismic data, reef oil-field seismic data, and data from several boreholes led to the identification of two areas of reef carbonate reservoirs in deepwater areas (water depth >= 500 in) of the Qiongdongnan Basin (QDNB), northern South China Sea. High-resolution sequence stratigraphic analysis revealed that the transgressive and highstand system tracts of the mid-Miocene Meishan Formation in the Beijiao and Ledong-Lingshui Depressions developed reef carbonates. The seismic features of the reef carbonates in these two areas include chaotic bedding, intermittent internal reflections, chaotic or blank reflections, mounded reflections, and apparent amplitude anomalies, similar to the seismic characteristics of the LH11-1 reef reservoir in the Dongsha Uplift and Island Reef of the Salawati Basin, Indonesia, which house large oil fields. The impedance values of reefs in the Beijiao and Ledong-Lingshui Depressions are 8000-9000 g/cc x m/s. Impedance sections reveal that the impedance of the LH11-1 reef reservoir in the northern South China Sea is 800010000 g/cc x m/s, whereas that of pure limestone in BD23-1-1 is > 10000 g/cc x m/s. The mid-Miocene paleogeography of the Beijiao Depression was dominated by offshore and neritic environments, with only part of the southern Beijiao uplift emergent at that time. The input of terrigenous sediments was relatively minor in this area, meaning that terrigenous source areas were insignificant in terms of the Beijiao Depression: reef carbonates were probably widely distributed throughout the depression, as with the Ledong-Lingshui Depression. The combined geological and geophysical data indicate that shelf margin atolls were well developed in the Beijiao Depression, as in the Ledong-Lingshui Depression where small-scale patch or pinnacle reefs developed. These reef carbonates are promising reservoirs, representing important targets for deepwater hydrocarbon exploration. (C) 2008 Elsevier Ltd. All rights reserved.

末次冰期以来西赤道太平洋边缘海古气候变化研究

本文所研究的区域是西赤道太平洋的两个边缘海盆-苏禄海和南中国海。这两个边缘盆地具有明显不同的水文特征，南中国海底层水冷（<4 ℃）并且通气较好（溶解氧浓度>1.75ml/l），而苏禄海底层水温暖（>10 ℃）并且含氧量低（溶解氧浓度<1.25ml/l）。这些不同的水文特征导致了不同的沉积环境，同时两个海盆的沉积记录也包含了这些水文条件在不同地质时间上如何变化的历史。笔者分别对南中国海的GGC-6孔（12°09'1''E，118°03'9''，水深2775米）和苏禄海的GGC-29孔（8°17'7''E，118°49'9''N，水深1535米）的浮游和底栖有孔虫动物群进行了系统地分析鉴定和统计，并用转换函数对古温度进行了分析，力求通过有孔虫化石群的面貌和定量古生态分析来反映古气候的变化。通过对浮游有孔虫氧同位素环境效应的分析来探索本区的古气候变化。此外还对沉积物中的有机碳和碳酸钙的含量进行了测试和分析。通过上述工作我们得出以下几点认识：1、氧同位素和古水温记录可分末次冰期和全新世两期，由于岩心的长度所限地质记寻年代较短为24000年左右。2、浮游有孔虫G.Grassaformis的最后出现是苏禄海末次冰期极盛时（～18000B.P）重要的地质界线。3、发现在北欧地区短暂寒冷的仙女木期（Younger dryas）在本区也有发现。这在一定程度上说明了仙女木期存在的全球性。4、本区末次冰期与全新世的夏季表层古水温相差不到2 ℃与CLIMAP（1976）赤道太平洋末次冰期以来古水温度的模拟结果相附。冬季表层水温相差较大为3.5 ℃左右。5、瓷质壳底栖有孔虫的繁盛和翼足类的大量保存是苏禄海冰期时底层暖水的良好指示标志。6、本区有机碳的含量反映了底层水含氧浓度的变化。高有机碳代表低氧浓度，低有机碳代表高氧浓度。南中国海一直受到西北太平洋水体的影响，致使其底层水一直处于充氧状态，只是在冰期最盛时稍有降低。而苏禄海底层水氧浓度较低，尤其是末次冰期极盛时隔绝状态加强，大量的降水使表层海水淡化分层，致使底层水缺氧状态加剧。7、本区做为西赤道太平洋的边缘海，其CaCO_3旋回模式却与太平洋相反，而与大西洋一致，即冰期碳酸钙含量低，全新世冰后期碳酸钙含量高。冰期陆源物质供应的加强和全新世浮游有孔虫生产力的提高是控制本区碳酸钙旋回的主要因素。此外，冰期海水溶解作用的加强是南中国海冰期低CaCO_3含量的另一个重要原因，而苏禄海的碳酸钙沉积受海水溶解作用的影响却很小。8、浮游有孔虫N.dutertrei的大量增加和相对较轻的δ~(18)O值说明冰期最盛时海水表面的盐度较低。末次冰期时东南亚地区东北季风加强西南季风减弱，由于特殊的地理环境使本区在冰期时降水大量增加。

一次降水过程对青藏高原高寒草甸CO_2通量和热量输送的影响

青藏高原高寒草甸的热量输送和碳收支对气候变化的响应十分敏感，降水过程对其影响较为复杂。利用三维超声风速仪和红外CO_2／H_2O分析仪，以及常规微气象要素的涡度相关观测系统，分析了2002年8月8—17日的一次降水过程对青藏高原高寒草甸CO_2通量和热量输送的影响。结果表明：降水过程使气温、地温和辐射等有所降低，大气湿度和CO_2通量有所升高；气温、地温、总辐射、地表反射辐射、光合有效辐射（PAR）、净辐射、土壤热通量、潜热通量和显热通量分别下降了23．3％、23．1％、61．9％、58．9％、61．7％、57．9％、268．3％、61．6％和71．0％，大气湿度和CO_2通量分别升高了27．0％和38．6％；降水削弱了PAR对白天净生态系统CO_2交换量（NEE）的影响，而增加了地温对夜间呼吸的控制；降水强度对白天NEE几乎没有影响，但能降低夜间呼吸。

试谈禾本科植物生殖器官主要性状的分类价值及其适用等级

生殖器官性状一直是禾本科植物分类的主要依据，但由于各个性状所附实体的形态特点，着生位置，发育程度和环境饰变的差异，其分类价值是不尽相同的，为了克服该类性状使用上的种种弊病，本文特对主要宏观性状的分类价值进行了评述，总结了它们在应用中各自适宜的等级范围，其中象花序的类型，小穗的着生，小花和果实的形状等价值较高，通常适合于族级以上烘群的划分，花序的形状，小穗的排列，果料的类型等价值偏低，通常 适合于属，种级类群的区分，而花序 的长短与粗细，小穗轴，内稃等价值较低，通常适合于种级或种级之下类群的鉴分。

层序地层分析在非油气领域的应用进展及前景评述

层序地层分析已在油气勘探中发挥重要作用。相比而言，其在非油气领域的应用尚处于起步阶段。文章论述了层序地层分析的基本内容及其在非油气领域的应用进展；从油气与非油气矿床成矿、富集规律的相似性和两者的共生性，以及层序界面、沉积体系域与成矿基本要素和条件的耦合性．评述了层序地层分析在非油气领域的应用具有广阔的前景；同时又针对油气与非油气矿床在成矿方面的差异性和海、陆相层序地层的差异性，指出了层序地层分析应用于非油气领域时应注意或需研究的一些问题.