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全新世以来江汉平原地形及其环境变化探讨
The Terrain and Climatic Change of Jianghan Plain since Holocene
 [PDF]

陈思思,
Geographical Science Research (GSER) , 2014, DOI: 10.12677/GSER.2014.34005
Abstract:
本文以江汉平原的钻孔作为研究对象,收集了10个位于江汉平原WE向的钻孔资料。这10个钻孔资料都是前人发表的数据,综合分析这些钻孔数据,绘制出了江汉平原自西向东地层联孔图。通过对钻孔数据的分析,重建了全新世以来江汉平原地形变化和环境变化。结果显示,全新世以来江汉平原的地形和气候变化可以分为三个阶段:在全新世初期(10~7ka BP),江汉平原大部分地区相对平坦,秦市乡潭彩剅村和沔城一带相对比较低洼,这一时期主要受到河流切割作用;全新世大暖期期间(7~3ka BP),由于长江和汉江等河流洪泛沉积发育,洪水携带的沉积物在秦市乡潭彩剅村和沔城一带相对比较低洼的地方快速堆积;约3ka BP时,江汉平原的地形和全新世初期比已经有了很大变化,很多低洼的地方和一些深的凹槽已经基本上被填平,地形起伏变得缓和,此后江汉平原的地形受人类影响越来越大。
Based on the borehole of Jianghan Plain as the research object, the date of 10 boreholes located in the East-West of Jianghan Plain were collected. These data were published by previous studies. Stratigraphic map from west to east of the Jianghan Plain is drawn out through comprehensive analysis of these drilling data. Through the analysis of drilling data, the terrain and climatic change since Holocene have been reconstructed. The research result shows that terrain and climatic changes of Jianghan Plain can be divided into three stages as follows: in 10 - 7 ka BP, most of the regions were relatively flat. Tancaidou village in Qinshi country and Miancheng area were relatively low. This period were mainly formed by river cutting action; during 7 - 3 ka BP because of the Yangtze river and Hanjiang river flood deposit development, the sediment carried by flood accumulate rapidly in relatively low area of Tancaidou village in Qinshi country and Miancheng area; ~3 ka BP many low-lying areas and some deep grooves have basically been filled. Then Jianghan Plain terrain influenced by human is growing.
基于EOF的雅鲁藏布江流域干湿季降水变化的时空分异研究
Analyzing Spatial and Temporal Distribution of Precipitation at Wet or Dry Season in Yarlung Zangbo River Basin Using Empirical Orthogonal Function
 [PDF]

, 陈思思, 张嘉琪
Open Journal of Soil and Water Conservation (OJSWC) , 2014, DOI: 10.12677/OJSWC.2014.24004
Abstract:
根据2000年~2010年雅鲁藏布江流域的15个气象站点的月值降水数据,采用经验正交函数分解法(EOF),分别计算出雅鲁藏布江流域干湿季降水的时空分布特征和时间系数序列。结果表明:应用EOF方法可以很好地揭示降水场的时空分布特征,且对雅鲁藏布江流域而言前4种模态揭示了四种分布场,干季降水的累计贡献率达99.84%,湿季降水的累计贡献率达89.81%。雅鲁藏布江流域干湿季降水的主要空间分布特征是“东–西差异分布”,即表现出西部偏少东部偏多的特点,尤其是在喜马拉雅山脉最东端的米林宽谷地带降水最为丰富,分析其原因是季风气候和印度洋的暖湿气流对东部影响较大,西部由于海拔高,水汽很难到达,因此西部降水较东部少。
According to the monthly precipitation data of 15 meteorological stations in the Yarlung Zangbo river basin during the period from 2000 to 2010, and using the method of empirical orthogonal function (EOF), we respectively calculated the spatial and temporal distribution characteristics of precipitation in wet and dry season and the time-coefficient series. The results showed that the EOF method was capable of revealing the spatial and temporal distributions of precipitation field for the Yarlung Zangbo river basin, with the first four EOFs reflecting the four vector distribution fields; furthermore, we can know that the cumulative contribution rate of precipitation is 99.84% at dry season and 89.81% at wet season. The main space distribution characteristic of dry or wet season precipitation is different distribution from west to east in Yarlung Zangbo river valley. It shows that the precipitation in western district is more than that in eastern district, such as Milin wide valley in the eastern end of Himalayas, which is one of most abundant precipitation areas, because it is influenced by the monsoon climate and the warm moist air flow from the eastern Indian Ocean. However, due to the high altitude, the water vapor is hard to reach the west area. So the precipitation of west area is relatively less compared to the east.
基于CdTe和CdSe量子点体外PDT灭活白血病 HL60细胞实验研究
Experimental Research on the Vitro Inactivation of HL60 Cells Based on CdTe and CdSe Quantum Dots
 [PDF]

贺宇路, 黄康强,, , 建文
Hans Journal of Biomedicine (HJBM) , 2012, DOI: 10.12677/hjbm.2012.21001
Abstract:
近年来,随着光动力疗法基础研究的不断深入,量子点作为潜在的光敏剂对癌细胞的灭活效应引起了人们的极大关注,实验利用羧基乙酸包覆的量子点CdTe和CdSe进行了QDs-PDT体外灭活HL60细胞的实验研究。实验结果表明:CdTe和CdSe的对HL60细胞灭活的最佳光照剂量分别为15 J/cm2和18 J/cm2,最佳作用浓度均为2.0 μmol/L;在最佳作用参数下两者的灭活效率分别为62.7%,83.0%,基于CdSe的QDs-PDT灭活效率优于CdTe。
Quantum dots used to destruct the cancer cells through the photocatalytic reaction has caused great attention in recent years. In the paper, thiol-capped CdTe and CdSe QDs were used to destruct the HL60 cells. The results showed that the best light irradiation dose of CdTe and CdSe were 15 J/cm2 and 18 J/cm2. The best concentration of additive QDs were all 2.0 μmol/L. The inactivation efficiency were 62.7% and 83.0% under the best destruction para- meters, respectively. Additionally, the destruction efficiency of CdSe is better than that of CdTe in the optimized condi- tions.
使用SO2/Air/N2气氛作为纯Mg及#br#AZ91D合金的熔炼保护*
,守美
金属学报 , 2014,
Abstract: 利用3种实验方法,研究了SO2/Air/N2气氛对纯Mg及AZ91D合金熔体的保护行为,运用X射线衍射仪(XRD)、扫描电镜(SEM)、能谱仪(EDS)、Auger电子能谱仪(AES)和X射线光电子能谱仪(XPS)分析了形成的表面膜的相组成、微观组织形貌和生长过程,结合热力学计算讨论了表面膜的生长与保护机理,并考查了表面膜的稳定性.研究表明在SO2/Air/N2气氛中,保护性表面膜由MgO,MgS和MgSO4混合组成,MgSO4是热力学稳定相,它的形成至关重要.当采用SO2/Air/N2气氛为保护气氛且SO2含量一定时,Air含量不能过高也不能过低.
密封熔炼条件下含SO2混合气体对AZ91D熔体保护的研究
,守美
材料工程 , 2011,
Abstract: 在一次性充入含一定比例SO2的氮气的密封炉内,研究了SO2浓度、熔炼温度和加入CO2气体对AZ91D镁合金熔体的保护效果,并对表面膜形貌和成分进行了研究。结果表明AZ91D合金表面都有菜花状氧化物生成,提高SO2气体浓度,AZ91D合金被保护面积增加;升高温度,镁合金保护效果下降明显,700℃时便完全得不到保护。成分分析表明菜花状氧化物主要为MgO,生成的表面膜除含有Mg,O,Al元素外,还含有少量的S元素;当加入一定量CO2时,镁合金保护效果得到提高,膜中生成了无定形C。
不同专用小麦胚乳细胞淀粉体的比较研究
, , 陈刚 , , 李波
扬州大学学报(农业与生命科学版) , 2005,
Abstract: ????以两种不同优质专用小麦(扬麦9号,烟2801)为研究对象,用电子扫描显微镜观察成熟籽粒结构,分析胚乳细胞淀粉体的差异。结果表明:两个品种的胚乳细胞淀粉体均为单粒淀粉,淀粉体形状可分为Ⅰ、Ⅱ、Ⅲ3种类型,Ⅰ型为饼形大淀粉体,Ⅱ型为椭圆形中型淀粉体,Ⅲ型为近圆球形小淀粉体,大淀粉体通过网状膜与小淀粉体相连;两品种颖果的腹部和背部以Ⅰ、Ⅱ型淀粉体较多且排列紧密,发育较好,而中部以Ⅰ、Ⅲ型淀粉体为主且排列疏松,发育较差;烟2801胚乳细胞淀粉体发育较好,淀粉充实度高,蛋白质体多且与淀粉体结合更紧密。
洱海生态环境研究现状及存在问题
The Research Status and Problems on Ecology and Environment of Lake Erhai
 [PDF]

蔡燕凤, 张虎才, 陈光杰, 段立曾, 张自强, , 李华勇
Advances in Geosciences (AG) , 2013, DOI: 10.12677/AG.2013.34034
Abstract:
近年来,随着洱海生态环境的日益恶化和流域大面积快速开发,洱海的生态环境问题引起了国内外学者的广泛关注。本文对上世纪50年代以来在洱海所做的研究工作进行分析、总结,对洱海环境(包括洱海富营养化、重金属污染、流域开发和植被状况)、生态(包括生物多样性、食物链变化、生态系统特征变化)方面的研究现状进行了分析,结合所得数据进一步分析了气象因素(气温、降水与风速)与水质变化的关系,指出洱海及流域研究中还存在许多问题与不足(如蓝藻爆发历史、对浮游动物和食物链的详细研究、区分多重压力对洱海富营养化的驱动强度)。以期对洱海生态、环境的情况有一个综合了解,为以后在洱海继续开展相关科研工作提供一定的认知基础,更好地为洱海的生态修复工作提供建设性意见。
There are wide concerns from scholars at domestic and overseas on the ecological environment of Lake Erhai recently as a consequence of worsening status, massive and rapid development on the catchment of Lake Erhai. This paper summarizes the research status of Lake Erhai which has been collected since 1950s, analyzes the current situation of the environment (including eutrophication, heavy metal pollution, and catchment development and vegetation status) and ecology (including biological diversity, food web change, and characteristics changes of ecological system), and makes a further analysis on the meteorological factors (including temperature, precipitation and wind speed). Through those data we point out that there are some problems still exist in the research of Lake Erhai, for instance, the Cyano- phyta explosion history, the detailed research on zoo-plankton and food chain, the distinction of drive strength of multi- ple pressure on the process of eutrophication of Lake Erhai for the purpose that we can have a comprehensive under- standing of the situation on ecology and environment of Lake Erhai. In this way we can have cognitive bases for the further relative work carried out in Lake Erhai and support some constructive opinions for ecological restoration work of Lake Erhai preferably.
PEG胁迫下水稻根外皮层厚壁细胞的解剖学研究
孔妤 , , , 顾蕴洁 , 邓亚萍
扬州大学学报(农业与生命科学版) , 2008,
Abstract: ????通过PEG模拟干旱胁迫,采用Spurr树脂半薄切片结合显微观察的方法,比较水稻和旱稻根外皮层边缘厚壁细胞的形态差异,研究根外皮层边缘厚壁细胞加厚的规律。结果表明:随PEG浓度的升高,水稻(扬稻6号)根外皮层边缘厚壁细胞的胞壁宽度明显增加;旱稻(中旱3号)对低浓度PEG胁迫不太敏感,当PEG浓度达50g?L-1以上时,根外层厚壁细胞表现出明显加厚的趋势,且随PEG胁迫时间延长,厚壁细胞栓质化程度变高。推测水稻根系在干旱胁迫条件下具有一定的缓冲能力,外皮层边缘厚壁细胞在根外层导水率方面发挥显著的质外体屏障作用,可有效地防止水分丧失,保护根组织免受干旱的伤害。
绕线转子无刷双馈电机的链型等效电路模型
,雪帆,张经纬,阚超豪
电工技术学报 , 2010,
Abstract: 为了建立准确的无刷双馈电机等效电路和分析谐波对电机性能的影响,从该类电机的基本电磁关系出发,在其基波等效电路的基础上,提出谐波等效电路,建立考虑谐波影响后的链型等效电路模型,并给出该等效电路模型中参数的计算公式和状态方程。以一台实际的绕线转子无刷双馈电机为例,利用链型等效电路模型,对样机的机械特性进行计算,并和基波等效电路模型的计算结果、实验结果进行对比分析。样机的计算结果和实验结果对比表明,本文给出的等效电路模型和计算方法是正确的。
施氮对优质小麦颖果腹部和背部胚乳细胞物质充实的影响
,余徐润,张琛,周亮,
麦类作物学报 , 2013, DOI: 10.7606/j.issn.1009-1041.2013.05.019
Abstract: 为直观揭示施氮对小麦籽粒灌浆的生理效应,以徐麦30(强筋小麦)和扬麦13(弱筋小麦)为材料,采用树脂包埋样品进行半薄切片和ImageProPlus图像分析软件从形态学角度研究了孕穗期施氮对小麦颖果腹部和背部胚乳细胞物质充实的影响。结果表明,施氮后颖果腹部和背部胚乳细胞蛋白体数目增加,花后11、15和19d最显著,同时蛋白体的聚集方式发生改变,对照组(不施氮)胚乳细胞内以小蛋白体为主,呈散状分布,而施氮组胚乳细胞含有许多大蛋白体或蛋白聚积体,分布较为集中。徐麦30蛋白体发育对氮素的响应程度高于扬麦13。施氮后腹部胚乳细胞淀粉粒排列更为紧密,细胞充实率增加,且扬麦13的响应程度大于徐麦30。施氮也增加了徐麦30背部胚乳细胞充实率,而对扬麦13的影响表现相反。
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