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Search Results: 1 - 10 of 191459 matches for " 郭晓玉 "
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中国南方暴雨日数的气候变化特征
Climate Change Characteristics of Rainstorm Days in South China
 [PDF]

陈少勇,, 俊瑞,
Climate Change Research Letters (CCRL) , 2015, DOI: 10.12677/CCRL.2015.44026
Abstract:
本文利用中国南方地区225个测站1961~2010年逐日降水量资料,采用趋势分析、Monte Carlo检验、滑动T检验、Mann-Kendall分析等方法,分析了50年来南方地区暴雨日数的时空分布特征及其变化规律。结果表明:华南、长江中下游平原和成都平原是相对多暴雨区。大多数地方暴雨日数趋势不显著,东部略有增多,西部略有减少趋势。但成都平原显著减少,1992年发生突变,长江中下游的暴雨日数有较明显的增多趋势,1986发生突变;在季节分布上,冬季最少,夏季最多,春季多于秋季。冬季暴雨主要出现在华南,略有增多趋势;春季主要出现在华南、长江中下游平原,变化趋势不明显;夏季暴雨最多且有显著增多趋势。其中,华南略有增多,长江中下游显著增多,成都平原显著减少;秋季主要出现在滇南–华南–浙西等沿海地区,无明显趋势;受东亚季风影响,南方各地暴雨日数都为单峰型,其中成都平原8月为峰值,其余各地6月为峰值,成都平原暴雨集中在7~8月,长江中下游平原集中在5~6月,华南集中在5~8月。在全球气候变暖背景下,中国南方暴雨日数响应气候变化,增温显著区,暴雨增多,增温不显著区,暴雨减少。
Using the day by day precipitation data at 225 stations in the south area of China in the period of 1961-2010, with the trend analysis, Monte Carlo test method, the sliding T test, Mann-Kendall, etc., the spatial and temporal distribution characteristics of rainfall day and evolution rule above rainstorm in the south of China for 50 years are analyzed. Results show that the Southern China, the middle and lower reaches of Yangtze River and the Chengdu Plain are relatively more rains-torm areas. Rainstorm day trend is not significant in most areas; there is a slight increase in the east and a slight decrease in the west. But rainstorm days have significantly reduced in Chengdu Plain. There was a remarkable mutation in 1992. Rainstorm days of the Yangtze River have an obvious increasing trend. There was a remarkable mutation in 1986. As for seasonal distribution, it is the least in winter and most in summer. It is more in spring than in autumn. Winter rainstorm mainly occurs in southern China and it has a slight increasing trend; spring rainstorm mainly occurs in southern China, the middle and lower reaches of Yangtze River. It changes insignificantly. Rainstorm in summer is the most and has a significant increase trend. Among them, a slight increase is in southern China and an obvious increase is in the middle and lower reaches of Yangtze River. It reduces significantly in Chengdu Plain; in autumn. Rainstorm occurs mainly in southern Yunnan-southern China-western Zhejiang and other coastal areas, no clear trend; rainstorm days of south areas form a unimodal sequence. Chengdu Plain reaches its peak in August and the rest areas reach the peak in June. Rainstorm of Chengdu Plain mainly occurs in the period from July to August. It is concentrated in the period of May to June in the middle and lower reaches of Yangtze River. It is concentrated in the period of May to August in southern China. Under the background of global warming, rainstorm days in the south of China are response to climate change.
药用植物罗勒同源多倍体诱变的初步研究
Preliminary Study on Autotetraploid Mutagenesis of Medicinal Plant Ocimum basilicum
 [PDF]

小英, 杨娜,,
Hans Journal of Agricultural Sciences (HJAS) , 2014, DOI: 10.12677/HJAS.2014.41003
Abstract: 采用秋水仙碱琼脂凝胶涂抹法,处理罗勒(Ocimum basilicum)幼苗茎尖生长点,研究罗勒同源四倍体种质创新的最佳诱变时间。实验证明,0.2%的秋水仙碱诱变72 h,诱变率最高,为32%。和对照株形态比较得知,诱变株矮壮,节间缩短;子叶大且肥厚,脱落时间延迟;生长发育受抑制;真叶出现晚,叶形不对称,叶面凹凸不平,出现卷曲叶、勺状叶等变异;叶色浓绿。统计学分析表明,诱变株较对照株,株高显著降低,第一节间距显著缩短,茎杆显著增粗,叶形指数显著减小,叶绿素含量显著升高,叶片厚度显著增加,第一真叶下表皮单位面积气孔数显著减少,每气孔叶绿体数显著增多,气孔长宽比显著减小。从诱变株与对照株的初步形态变异表明,罗勒的多倍体诱变是成功的, 诱变株的细胞学鉴定和性状稳定还有待于进一步的研究。
 The seedling apical bud of Ocimum basilicum was painted with colchicine semi-solid in this research. We focused on the best duration time of colchicine and agar on autotetraploid mutagenesis of this medical plant. The result showed that 0.2% colchicine conducted on O. basilicum for 72 h with the highest mutation rate at 32%. Compared to the controls, the mutants had much shorter internodes, more stocky plants, bigger and thicker
市场势力对新建商品住房溢价的影响:基于北京市微观样本的实证检验
,刘洪
系统工程理论与实践 , 2013,
Abstract: ?对于市场结构的微观研究一直是住房市场研究的重要方向之一,而国内新建商品住房市场由于开发商集中供应的特点,决定了研究卖方市场势力程度及其影响规律的重要性.论文利用北京市新建商品住房市场微观数据,测算了1029个新建商品住房项目的需求价格弹性和其中494个弹性项目的lerner指数,得到了北京市新建商品住房市场垄断程度的空间分布情况,并在此基础上实证检验了新建商品住房项目市场势力对住房交易溢价水平的影响.实证结果表明,市场势力每提高1%,新建商品住房的交易溢价将平均提高0.83%,且该结果对不同子市场具有良好的稳健性.此外,论文还从需求价格弹性角度解释了开发商"捂盘惜售"现象.
政府土地供应决策中等待期权的实证检验
,刘洪
系统工程理论与实践 , 2013,
Abstract: ?论文实证证明了在我国城镇现行土地供应和管理的制度背景下,地方政府在土地出让过程中拥有一定的等待期权.根据等待期权的行权原理和一般性检验思路,论文在久期模型的框架下构建了基于韦伯分布假设的最大似然实证检验模型,并利用北京市居住用途土地出让数据和住房市场数据,实证检验了北京市政府在土地出让过程中的等待期权特征.实证结果表明,北京市住房市场风险水平每增加1个标准差,政府土地出让风险率将稳健地降低20%以上,这一结论支持了在土地出让过程中政府拥有等待期权的假设.
应用聚类分析建立Z246井区长8油藏单井产能预测图版
 [PDF]

, 康永梅,, 亚丽
Journal of Oil and Gas Technology (JOGT) , 2015,
Abstract:
马岭油田属于特低渗透油藏,成藏机制复杂,储层非均质性强,具有有效储层的预测和评价难度较大的特点。由于物性条件差,单井产量低,稳产期短,甚至没有稳产期直接进入递减期,在开发过程中经常造成大面积低产区的出现。从单井产量递减率的规律出发,应用聚类分析方法,对Z246井区长8油层组的45口采油井物性进行划分,选取孔隙度、渗透率、泥质含量和流动带指数等参数作为分析判别依据,划分三类物性特征区,建立单井日产量与储层物性参数(渗透率、含油饱和度和地层厚度)及储层改造参数(加砂强度)的多元线性函数,结合压力保持水平及综合递减率的相关关系式,建立了三类初期产能图版,为开发初期的产量预测提供了积极的指导作用。
等离激元在薄膜太阳能电池中的研究进展
Research Progress of Surface Plasmon Applied in Thin Film Solar Cells
 [PDF]

, 王新占, 戴万雷, 路万兵, 少刚, 于威,
Applied Physics (APP) , 2011, DOI: 10.12677/app.2011.13017
Abstract:

为了更高效地把光能转化为电能,研究人员尝试着在薄膜太阳能电池设计中引入金属纳米粒子的等离激元结构。通过等离激元对光的引导和限制,在降低电池的吸收层的物理厚度的同时能够保持薄膜电池较强的光吸收特性,在制备便宜高效的薄膜电池领域具有重大应用潜力。本文调研了等离激元在太阳能电池领域应用的最新进展情况,阐述了等离激元作用薄膜太阳能电池的机理,并对未来基于等离激元的太阳能电池设计进行了展望。
In order to transfer light to electricity efficiently, thin film solar cells with the structure of supporting surface plasmons in metal particles are designed. Due to the surface plasmons can guide and localize lights, the physical thickness of solar photovoltaic absorbing layer can be decreased as well as the absorption in photovoltaic devices can be improved. This technology plays an important role in fabricating low-cost and high-efficiency thin film solar cells. In this review, the latest progress of the application of plasmonics in solar cells is researched, the mechanism of the intersection of plasmonics and photovoltaics is expounded, and an outlook on the future of solar cells based on these principles is offered.

玉米穗腐病样品中黄色镰孢的分离鉴定及rDNA-ITS序列分析
,魏宏,满库,何苏琴,建国,
草业学报 , 2013,
Abstract: 为了明确甘肃玉米穗腐病的病原菌,于2009年9月在甘肃省四大生态区采集玉米穗腐病样品,以组织分离法进行病原物的分离培养,对分离得到的镰孢菌菌落进行纯化和单孢分离后,以形态学为基础,参照Leisle分类系统进行鉴定。结果表明,分离到271株镰孢菌菌株中有105株经形态学鉴定为黄色镰孢,占分离镰孢菌的38.7%。分析发现黄色镰孢种群数量随采样区而异,陇东和陇南地区采集的样品中分离频率分别为52.0%,55.4%,本研究充分证明了黄色镰孢是甘肃省陇东和陇南地区玉米穗腐病的优势病原菌。按照柯赫氏法则用混合菌株接种法对沈单16和金穗96832进行致病性测定,证实了黄色镰孢对玉米果穗的致病性。随机选取3株黄色镰孢菌株进行rDNA-ITS基因序列分析,将PCR产物回收测序后在GenBank上比对,菌株3-1-1与GenBank中登记的黄色镰孢菌株K1004和K216、6-4-1和21-2-1与黄色镰孢菌株CBS122.73亲缘关系最近,同源性达99%。利用DNAStar软件绘制其系统发育树状图,结果表明,菌株3-1-1与K1004和K216、菌株6-4-1和21-2-1与CBS122.73位于系统发育树的同一分支,聚为一类,与形态学的鉴定结果一致。
无底柱分段崩落法开采地表移动分析的粘-弹性力学模型
李文秀,,
工程力学 , 2009,
Abstract: 采用无底柱分段崩落法开采所引起的地表移动过程是一个复杂的过程。该文根据岩石流变学理论,给出无底柱分段崩落法开采地表下沉预计分析的粘-弹性力学理论模型,并对鲁中冶金矿业集团公司小官庄铁矿无底柱分段崩落法开采工程实例进行了具体的计算分析。通过运用该文给出的粘-弹性力学理论模型,对小官庄铁矿地表下沉量进行了预测,计算分析了小官庄铁矿西采区地表下沉随时间变化的地表动态下沉过程。将理论分析结果与现场工程实测资料进行了对比,发现二者吻合较好,表明该文提出的方法可用于预计分析无底柱分段崩落法开采所引起的地表移动问题。
油烟废气高效降解菌的选育与降解特性
郑连英,缪建,
化工学报 , 2004,
Abstract: 从受油烟污染的土壤中分离筛选出4株菜油降解菌株.试验表明,4株菌株能够不同程度地降解菜油.菌株Z1表现出较强的降解能力,该菌最适生长条件为:温度30℃,pH=7,摇床转速210r?min-1,接种量1%.在空塔气速0.2~1.2cm?s-1、停留时间10~40s的试验范围内,选取木块为滤料,研究生物滤塔油烟废气的降解性能,分析了浓度、流量、湿度对降解能力的影响.试验运行结果表明,滤料微生物菌株Z1活性较强,对油烟具有较强的降解能力和抗负荷冲击力.
不同金属氧化物对等离子体降解甲苯的作用研究
,,叶代启
环境科学学报 , 2010,
Abstract: 常温常压下,研究介质阻挡放电(DBD)与4种金属氧化物催化剂(FeOx、MnOx、CuO、CoOx)联用降解甲苯废气.比较不同催化剂对甲苯去除率(η)、COx选择性(Scox)、副产物(O3、NO、NO2)产生量及能量产率(ηY)的影响.同时,用BET、XPS、H2-TPR、FT-IR等方法对催化剂进行表征,探究各种催化剂的不同作用.研究发现,FeOx的甲苯去除率及能量产率最高,而MnOx在分解O3和提高COx选择性方面效果最显著,但生成的NOx略高于其它催化剂.BET和H2-TPR的结果解释了4种催化剂的活性顺序:FeOx>MnOx>CuO>CoOx>无催化剂.XPS结果表明,使用过的锰催化剂有不同价态的C、N、O元素,且含有C—N,CO,C—O,CN或O—H键.FT-IR的结果进一步证实了这些键的存在,且发现可能有甲苯及其中间产物、苯甲醇和苯甲酰胺或其它酰胺物种存在,这可部分解释催化剂减少副产物生成量的原因.同时提出等离子体场下甲苯氧化机理.
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