High abundance of viruses found in aquatic environments

The concentration of bacteriophages in natural unpolluted waters is in general believed to be low, and they have therefore been considered ecologically unimportant. Using a new method for quantitative enumeration, we have found up to 2.5 x 10(8) virus particles per millilitre in natural waters. These concentrations indicate that virus infection may be an important factor in the ecological control of planktonic micro-organisms, and that viruses might mediate genetic exchange among bacteria in natural aquatic environments.     

水产品中恩诺沙星药物残留检测方法研究进展

恩诺沙星属于喹诺酮类抗生素药物,具有广谱杀菌、耐药菌少等优点,被广泛用于水产养殖疾病的防治。该药物使用不当极易造成水产品中残留超标进而危害人体健康。主要从样品前处理技术和水产品中恩诺沙星残留检测方法两方面进行阐述,并对各种检测方法的特点进行分析讨论,以期为我国水产品中恩诺沙星残留的检测和监管提供参考。     

Progress in the study of tectophysicochemistry

Tectophysicochemistry is a research area that deals with the interrelations between physical and chemical changes of crustal materials caused by tectonism. A given tectonic force may be resolved into two parts: homogeneous stress and differential stress. Homogeneous stress refers to isotopic pressure, which is superimposed on the original pressure and affects the equilibrium of various chemical reactions. It is also a factor that influences petrogenesis,metallogenesis and metamorphism. Differential stress is commonly produced when external forces act on a given solid body. It may cause deformation of crustal materials and generate various kinds of structural features. Tectophysicochemistry pays special attention to pressure, temperature and other physicochemical conditions produced or induced by tectonism and studies the influences of additional tectonic parameters on various chemical equilibria, so it gradually develops into an independent area of science.     

太阳电池的研究和应用进展

简要介绍了太阳电池工作原理 ,并对现有太阳电池进行了分类。综述了现阶段国内外太阳电池的研究和应用进展     

瘦素在临床研究中的进展

瘦素研究近年来的发展多注重基础紧密联系临床,积极转化为临床实践,血清瘦素测定、质量浓度与胰岛素抵抗的关系、脑梗死与瘦素的关系以及脂肪肝与瘦素的关系都是学者们高度关注的重要部分,能够转化到临床,成为有效的临床保护措施。     

浉河水生维管植物初步调查

对信阳市区浉河水生维管植物进行了初步调查．浉河水生维管植物多发生在枯水期，共有18科、32种、3变种．其中以湿生植物为主，占54．3％，沉水植物次之，占25．7％，浮水植物占11．4％，挺水植物占8．6％，浮水兼湿生植物占2．9％。     

汞污染土壤的改善研究

大工业的发展,代表了社会文明的进步,但是,在经济发展的同时,应重视对环境的影响。通过对贵州有机化工总厂周边环境土壤的汞污染研究,拟寻找汞污染土壤后的治理方法,改善土壤质量。     

基因调控网络研究进展

基因调控网络是一种连续而复杂多变的动态网络系统,是细胞内各种信号因子之间相互作用关系的整体表现.近些年来,很多物种全基因组测序的完成、高通量实验技术的发展以及高性能分子生物学工具的应用,使得构建一个复杂和相对完整的基因调控网络成为可能,从而使绘制整个活细胞内各种基因表达的调控网络成为当前研究的热点.作为系统生物学的核心领域,构建和分析基因调控网络将有利于我们更系统地剖析细胞的功能,更深刻地洞见生命的本质.综述关于基因调控网络研究的基本原理和方法,为今后进行更深入的研究和探讨打下良好的基础.     

白杨素及其磺化配合物的研究进展

白杨素及其磺化衍生物具有广泛的药理活性,分子结构中具有的完整π键共轭体系,强配位氧原子及合适的空间构型,可与金属离子配位形成稳定的环状配合物。一系列白杨素及磺化衍生物的配合物已被合成,其结构通过光谱手段和x射线单晶衍射确定。研究表明这些配合物结构新颖、性质独特。其中Ca（Ⅱ）、Zn（Ⅱ）与白杨素磺化衍生物所形成的配合物具有强的光致发光现象,是新型的光致发光材料。     

合成意托啡与氢化意托啡去甲基方法的改进

本实验对意托啡及氢化意托啡去甲基方法进行改进．采用二苯膦盐代替原氢氧化钾对(Ⅱ)或(Ⅵ)3位选择性去甲基,产品得率由原43％提高达60％以上．这一方法的改进,同时还解决了原工艺产品质量差、后处理困难及存在的劳动保护问题．     

氧化脱除燃煤烟气中元素汞的实验研究

我国是燃煤大国,元素汞是燃煤烟气排放过程的主要有害痕量元素之一,毒性很强,给人类健康和生态环境带来了极大的影响。燃煤过程中汞的排放,特别是大型燃煤电厂的汞排放,在全球汞循环中具有相当大的危害性,所以煤炭开采与利用过程引起的汞污染问题应当引起广泛重视,如不采取一定措施加以控制,将会造成难以弥补的危害。燃煤电厂所引起的环境污染非常严重,控制汞的排放已成为急需解决的环境问题。元素汞脱除的关键在于元素汞的价态转化,采用NH4Cl为氧化剂进行了模拟烟气中元素汞的氧化脱除实验,并考察了氧化剂浓度、反应温度、烟气滞留时间对元素汞氧化脱除的影响。结果表明,氧化剂浓度达到120 ppm,反应温度超过1 200 K,烟气滞留时间达到2 S时,燃煤烟气中的元素汞转化率可达到90%以上。     

中国啮齿目动物染色体核型研究进展

概括总结了国内已报道的啮齿目动物染色体核型的研究结果,综述了啮齿目动物染色体显带技术的概况以及最新进展,阐述了核型差异的产生原因．最后介绍了新技术在啮齿目动物染色体核型研究中的应用前景．     

不同环境中胞外多糖产生菌的初步研究(英文)

从不同的环境中采集样品,采用LB平板稀释法和苯胺蓝法分析样品中胞外多糖产生菌的丰度并分离胞外多糖产生菌;以发酵产糖量分析进行复筛,对产糖量较高的菌株进行常规生理生化分析和16SrDNA序列分析.结果表明:不同环境中胞外多糖产生菌的数量和类别有较大差异,其中活性污泥中胞外多糖产生菌数量最多;复筛得到89个菌株,选择其中8个产糖量较高的菌株进行生理生化实验和16SrDNA序列分析,结果显示:4个菌株属于芽孢杆菌属,另外4个可能属于新的细菌菌株.     

金属基树枝形聚合物的研究进展

树枝形聚合物是现代材料科学领域的一种新兴材料,结合31篇参考文献对金属基树枝形聚合物的合成和应用领域的研究成果进行了综述,展望了其应用前景。     

Progress in experimental study of aqueous lubrication

Aqueous lubrication is commonly regarded as friendly to the environment.We review current knowledge of the behaviors and mechanisms of aqueous lubrication.Major methods for investigating aqueous lubrication are addressed.We describe studies on both friction and film formation performance of various water-based lubricants,Additionally,we discuss possible underlying mechanisms of aqueous lubrication.Attention is also drawn to continuing topics of investigation and some unsolved problems.     

硫磺改性吸附剂脱除实验室中气态汞的实验研究

文章采用冷原子吸收法,选用经硫磺改性的活性炭和沸石对实验室中气态汞的吸附性能进行了实验研究。结果表明,改性后的活性炭和沸石对气态汞的脱汞率均有明显的提高,如对汞质量浓度560μg/m3的汞蒸气,负载8%硫的活性炭的脱汞率为90%,而未改性的活性炭的脱汞率为77%,负载8%硫的沸石相比于未改性的沸石的脱汞率由47%提升到67%。从经济角度分析,沸石脱汞比活性炭的经济效益更好。     

Progress report on the study of wood-decaying fungi in China

This study addressed three important aims:(1) undermining the previously obtained raw data about wood-decaying fungi(WDF) distribution and continuously investigating permanent plots to address certain scientific questions in ecology,(2) resolving the higher-level phylogeny of WDF with the help of multiple loci,and(3) testing and estimating the medicinal values of species that are closely related to well-known medicinal species.More than 1200 species and 2469 strains of WDF in China were identified from 28908 specimens collected from a series of field investigations.Using these materials,studies in multiple disciplines,such as ecology,taxonomy and phylogeny,and medicine,have been performed.With respect to ecology,the diversity of wood-decaying polypores significantly differed among a boreal forest zone,a temperate and warm temperate forest zone,and a tropical and subtropical forest zone.For instance,from north to south,the number and proportion of brown-rot species and the proportion of species found on fallen trunks were both decreased.The ecological patterns of wood-decaying polypores on gymnosperm and angiosperm trees were also explored by a case study in Northeast China.Although the total species richness was similar between the two tree groups,several other characteristics were significantly different,such as community structure and richness in certain substrates.The taxonomy and phylogeny of wide samples were referred to and their phylogenetic positions were resolved or at least partially established.In particular,phylogenetic knowledge about four genera,Fomitiporia,Ganoderma,Inonotus and Perenniporia,which include medicinal species,was essential for further research to determine the medicinal values of these types of fungi.Among these medicinal species,we mainly focused on Inonotus obliquus for its medicinal purposes.Polyphenols,polysaccharides and lanostane-type triterpenoids,extracted from the sterile conk of this species,could dramatically decrease levels of free radicals,DPPH and hydroxyl radicals,respectively.The metabolic profiles(both production and composition) of cultured I.obliquus mycelia could be altered by co-culture with other medicinal species or by induction of S-nitrosylation and denitrosylation,which may enhance the antioxidant capacity of I.obliquus.     

分布式环境下COM+事务管理组件优化机制研究

以分布式系统为平台,提出了COM+事务管理类组件在设计阶段和编程实现阶段的两段优化方案.设计阶段按照功能聚类的方法来划分组件和设计接口,编程实现阶段则充分利用了COM+服务进行编程设置优化,通过优化方案,有效地提高了COM+分布式组件的工作效率,给出了应用案例.     

气候变暖条件下中国西北地区地理环境演变趋势初探

在预测分析的基础上,探讨了因气温升高而引起的气候、植被、土壤、水文、地貌等自然地理要素的变化趋势     

水环境中石油烃类的TiO2光催化降解量子产率的测定

把反应速率常数和量子产率作为动力学常数,研究了石油烃类化合物的TiO2光催化氧化降解.并采用高光密度法,以K3Fe(C2O4)3做光露计,300 W中压汞灯为光源,在365 nm波长处测定石油烃类的反应速率常数和量子产率.结果表明:正十六烷、正癸烯和萘等石油烃类在365 nm波长下的TiO2光催化氧化降解反应均服从一级反应动力学,其反应速率常数分别为4.3×10-3、6.7×10-3和5.1×10-3m in-1.K3Fe(C2O4)3光解服从零级反应,其速率常数为5×10-5(mol/L)-1.m in-1;正十六烷、正癸烯和萘的量子产率分别为1.20、1.87和1.42,其值均大于1,进而表明了TiO2光催化氧化法对石油烃类化合物的降解反应可能有活性氧参与.