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381.
In the present study, genetic polymorphism and diversity in unicellular clones of Chlorella vulgaris Beijerinck and Chlorella pyrenoidosa Chick were studied with Inter Simple Sequence Repeats PCR (ISSR PCR). Samples including four clones of C. vulgaris and three clones of C. pyrenoidosa were purified by single-clone-choice method. For four C. vulgaris unicellular clones, the total number of the bands scored for 18 primers was 298; and the number of the polymorphic bands was 118, of which 39.6% were polymorphic. The size of PCR products ranged from 200 to 2 500 bp. The total number of bands scored for 18 primers, the number of polymorphic bands and the percentage of three C. pyrenoidosa unicellular clones was 194.83 and 30.8%, respectively. POPGENE analysis show that the average Nei genetic diversity (h^*) and Shannon index of diversity (I^*) in the four C. vulgaris unicellular clones was 0.2181 and 0.3208, respectively, which is slightly higher than those of the three C. pyrenoidosa unicellular clones (0.190 3 and 0.274 8), which agreed with the percentage of polymorphic bands in the mixed samples of the two species. The results suggest that ISSR is a useful method to Chlorella for intra-species genetic analysis.  相似文献   
382.
Synedra ulna var, repanda Q. X. Wang & Q. M. You, a new variety of Synedra (Bacillariophyta) from Xinjiang, China, is described and illustrated, and the characteristic of the variety: includes undulate-linear valves and straight pseudoraphe, differs from other species of Synedra.  相似文献   
383.
Inorganic lead (Pb) is one of the most common environmental pollutants. Much evidence indicates that Pb exposure could directly affect fish growth and development. In this study, we investigated the cytotoxic effects of Pb on cytoskeletal protein stability at both protein and mRNA level in crucian carp Carassius auratus. Pb(NO3)2 treatment in concentration of 100 μmol/L resulted in decreased expression of both α- and β-tubulin but γ-tubulin as assayed with SDS-PAGE, Western Blot, and ELISA. In vivo and in vitro analyses on protein expression of tubulins are consistent. The effect of Pb on mRNA expression varied among different tissues. Our results suggest that cytotoxicity of Pb at protein translation level is stronger than at mRNA expression level.  相似文献   
384.
曹雪芹在《红楼梦》中,精心塑造了两位女性形象,薛宝钗象征士子阶层的"修身治国平天下"的儒家思想人格。林黛玉象征士子阶层希望的"人格独立"的道家思想人格。她们既可"合而为一"又可"一分为二",是士子阶层社会生命和自然生命的两面。  相似文献   
385.
主要根据锡元素特性,研究利用氢化物发生法测定地质样品中锡含量。该方法简便、快捷,不用分离干扰元素,大大提高了分析测试速度,且通过国家一级标样的分析能够满足0.001%~1.00%含量的锡矿石的测试要求。  相似文献   
386.
The recent deep prospecting results in the Jiaojia area of Eastern Shandong Province indicate that the Jiaojia ore field composed of several individual gold deposits as previously suggested is actually an ultra-large gold deposit. This deposit covers an area of ~40 km2, and shows a structural control by the Jiaojia fault and its secondary faults. Gold orebodies generally occur along the same mineralization-alteration belt, and the main orebodies intersect with each other or exhibit a parallel or overlapping distribution. This deposit's reserves are estimated to be 1, 200t of gold, being the first gold deposit of more than 1000t gold reserves in China. The No. I-1 orebody in the Shaling-deep Sizhuang ore blocks holds gold reserves greater than 350 t, or 29 percent of the total reserves, followed by the No. I orebody in Matang-Jiaojia ore blocks with exceeding 150t gold reserves. This deposit mainly occurs in the footwall of the Jiaojia fault, and presents zoned patterns in mineralization, alteration and structures. The strongly mineralized zones agree with strongly altered and tectonically fractured zones. These orebodies display strataform-like, veinlike or lenticular shapes, and generally show characteristics of pinching out and reappearing, branching and converging, expanding and shrinking. The orebodies commonly occur along positions where the fault strike changes and in gentle locations with dips changing from steep to gentle. The main orebodies are parallel to the main plane of the orecontrolling fault, and tend to be gentle from the surface to the deep. The orebodies mainly plunge to the southwest, with plunge angle of 45°–60°. Orebodies near the main plane of the ore-controlling fault have more gold resource than those away from main fault zone. The slant depth of orebodies is generally larger than the length along its strike direction; orebodies become thick and gold grades become low from the shallow area to the deep area. Ore-forming fluids are H2O-CO2-NaCl±CH4 type with medium-temperature and moderate to low salinity. Sulfur isotopic values(δ34SCDT) for gold ores range between 11.08‰ and 12.58‰, indicating mixed sulfur sources; hydrogen isotopic values(δDVSMOW) range from-83.68‰ to-116.95‰ and oxygen isotopic values(δ18OV-SMOW) range between 12.04‰ and 16.28‰. The hydrogen and oxygen isotopes suggest that ore-forming fluids originated from primary magma, and mixing with a large amount of atmospheric water during the late stage. The Eastern Shandong Province gold deposits are associated with magmatic activities which have mantlecrust-mixed source, and also share some similarities with orgenic and epithermal hydrothermal gold deposits. Because Eastern Shandong Province gold deposits with unique metallogenic features and formation setting which are different from other gold deposit types in the world, we call it the Jiaojiatype gold deposits. The kiloton class Jiaojia gold deposit is related to fluid activities, extension and detachment resulted from thermal upwelling of magmas. The strong magmatic activities in the middle to late stage of early Cretaceous in Eastern Shandong Province lead to active fluids, and provided abundant ore-forming materials for gold depsoits. Moreover, many extensional structures resulting from crustal extension provided favourable space for orebody positioning.  相似文献   
387.
国家级矿产实物地质资料的筛选和管理意义   总被引:1,自引:0,他引:1  
国家级矿产实物地质资料是反映中国矿产资源成矿特点、展现全国矿产勘查与科技工作水平的实物地质资料。国家级矿产实物地质资料由国家实物库永久收藏管理,因此实物地质资料需要筛选。筛选包含2层含义,一是矿床的筛选,即具有典型性、代表性、特殊性的矿床;二是钻孔实物的筛选,即入选矿床最具有代表性的钻孔岩矿心。笔者对2层含义的筛选分别进行了阐述并制定了筛选依据和工作方法,使国家级矿产实物地质资料的筛选有章可循,具可操作性。最后,对全国矿产实物地质资料的管理提出了建议。  相似文献   
388.
Particulate matter emissions generated by agricultural field preparation and harvesting operations were measured remotely via aerosol lidar and sampled simultaneously with a variety of aerosol point samplers in order to quantify dust plume space and time dynamics and particulate mass and number concentrations. Data for two cotton operations (disking, harvesting) in a flood-irrigated field in New Mexico are presented. Dust plume dynamics varied with boundary layer meteorological conditions, especially atmospheric stability, with plume maximum height significantly lower under stable conditions. Plume tracking indicated little change in plume area with height under unstable conditions and plume movement depended on wind speed and direction. Particle mass distributions indicate approximately 50% of the measured PM10 mass was PM2.5, significantly higher than previously reported values, possibly due to the near-source nature of the samples collected here. Variability in plume movement matched the variability in short-term wind fluctuations and this variability helps explain why models that utilize long-term averages perform poorly when trying to capture plume dynamics for nonsteady sources such as tractor operations.  相似文献   
389.
390.
主要阐述如何利用UML(Unified Modeling Language)建模过程描述集中监控系统。文中给出了监控系统的结构、功能和运用UML技术描述系统的方法和实现过程,并列出了描述实例。  相似文献   
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