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Search Results: 1 - 10 of 321363 matches for " 王凤娇 "
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渗透率级差影响下的薄差层层间干扰研究
 [PDF]

, 刘义坤
Journal of Oil and Gas Technology (JOGT) , 2015,
Abstract:
以大庆油田某薄差层开发区为例,结合薄差层非均质特性建立层间干扰研究机理模型,对不同渗透率级差下采出程度的变化规律进行研究,并通过单层开采模型进行对比,最终确定薄差层多层合采渗透率级差界限。研究表明:薄差层层间干扰现象随渗透率级差增加而加剧;表外储层油水前缘突破后,日产油量和含水率随渗透率级差的变化加剧;与各层单独开采效果相比,在渗透率级差为20的情况下单层采出程度平均降低6.59个百分点;采出程度随渗透率级差的增加呈对数关系下降;充分考虑该类储层物性特征与矿场对薄差层采出程度的要求,综合确定薄差层有效开发渗透率级差应控制在20以内。研究成果矿场应用效果良好,对薄差层高效开发具有指导意义。
八面体硒化镍的制备及其催化性质研究
夏昆,,赵京
安徽大学学报(自然科学版) , 2013,
Abstract:
不同货币政策下我国物价水平的多元回归及Granger因果性分析
The Multiple Regression and Granger Cau-sality Analysis of China’s Price Level under Different Monetary Policy
 [PDF]


Finance (FIN) , 2016, DOI: 10.12677/FIN.2016.61003
Abstract:

本文通过对1990~2000年及1998~2013年两阶段时间序列进行多元回归分析,对比了两阶段不同货币政策下稳定物价的效果,并对货币供应量、CDP增长和汇率三个因素与物价进行了Granger因果性分析。研究结果表明两个阶段货币政策对物价的影响效果不同,紧缩性的货币政策应对通胀有较好的效果,而适度宽松的货币政策对拉动经济以及提高人民消费水平的效果较小;除货币政策影响外,第一阶段经济增长对物价的影响不显著,汇率变动对物价有正向作用。第二阶段经济增长与物价呈现正相关关系,而汇率与物价变动方向相反。Granger因果检验结果得货币供应量M2增速、GDP都是CPI的Granger原因,且GDP是M2的Granger原因。

In this paper, through the analysis of the two stages of time series regression in the year between 1990 to 2000 and in the year between 1998 to 2013, we compared the effect of price stability in the two different stages of monetary policy and then made a Granger Causality analysis of money supply, CDP growth, exchange rate and price index. Research results showed that the effect of two stages of monetary policy on the price was different, that was to say the tightening of monetary policy had a good effect against inflation, and the effect of moderate monetary policy on the economy and improving people’s consumption level was smaller; besides the influence of monetary policy, the first phase of economic growth had no marked impact on prices, however the exchange rate had a positive effect on prices. The second phase of economic growth and price presented positive correlation, while the exchange rate and price change were in opposite directions. The results of Granger causality test showed that money supply growth rate, GDP were the Granger cause of CPI, and GDP was the Granger reason of M2.

H-ZSM-5分子筛上环己烯芳构化反应历程的理论研究
左士颖,周丹红,任珏,
催化学报 , 2012, DOI: 10.3724/SP.J.1088.2012.20346
Abstract: ?基于76T簇模型,采用量子力学和分子力学联合的ONIOM2(B3LYP/6-31G(d,p):UFF)方法研究了H-ZSM-5分子筛上环己烯芳构化反应历程.结果表明,环己烯首先吸附在分子筛酸性位上,与酸性质子共同脱除一个H2分子后,在分子筛骨架氧上生成烷氧配合物中间体;然后再脱质子得到环己二烯,同时酸性位复原;再经历脱氢和脱质子历程,最后得到产物苯,并吸附在复原的分子筛酸性位上.计算得到脱氢的活化能依次为279.64和260.21kJ/mol,脱质子的活化能依次为74.64和59.14kJ/mol.所有脱氢反应都是吸热过程,生成表面烷氧活性中间体,随后的脱质子反应能垒较低,而且是放热过程.此外,比较了环己烯在分子筛酸性位上的三个竞争反应,即脱氢、质子化和氢交换反应的活化能垒,证明环己烯优先发生脱氢反应.
室内环境空气中尼古丁含量测定
平小红, , 裴玉梅, 韩晓鸥
中国公共卫生 , 2014, DOI: 10.11847/zgggws2014-30-06-50
Abstract:
医务人员艾滋病职业防护及医院感染知识与行为调查干预
刘兴,周玉红,
华西医学 , 2012,
Abstract: 目的 了解医务人员艾滋病职业防护和医院感染知识及行为的现状。方法 2011年7月采用问卷调查法,分别对干预前299名、干预后254名医务人员进行艾滋病职业防护及医院感染预防知识、态度、行为调查。结果 医务人员对艾滋病的基本知识知晓率较高(>85.0%),但对较深层的问题缺乏认识,“窗口期”知晓率18.7%,“蚊虫叮咬”知晓率15.1%,消毒知识知晓率10.7%,干预前后比较差异有统计学意义(P<0.01)。结论 应加强艾滋病职业暴露防护和预防医院感染知识的教育与培训,提高职业防护能力,以保障医务人员职业安全,预防艾滋病医院感染。
考虑桩-岩接触面流变的桩岩联合受力性能研究
,,昭空,蔡永昌
岩土力学 , 2014,
Abstract: 桩-岩接触面的性质对桩岩联合受力的状况有重要影响。大量的工程实践表明,桩-岩接触面存在显著的剪切流变现象。在前人研究的基础上,介绍了以位移协调法为基础的双曲传递函数迭代计算方法,并据此建立了一种可考虑桩-岩接触流变的桩岩联合受力迭代计算方法。与现场模型桩试验实测结果对比分析表明,双曲传递函数迭代计算方法能够较好地描述桩岩联合受力性能。当考虑了桩-岩接触面的剪切流变后,桩身各处轴力随时间的增长逐渐增加,直至趋于稳定,桩的轴力比不考虑流变时桩的轴力大。迭代计算结果与实测结果吻合较好,对桩岩联合受力性能的研究有一定参考价值。
多功能磁性复合微球的制备及超声特性研究
Synthesis of multi-functional magnetic composite microspheres and study on its ultrasound performance

娇娇,石国,飞龙,王公正
- , 2018, DOI: 1672-4291(2018)05-0045-06
Abstract: 设计并制备了一种新的亚微米级磁性复合微球,检测了该微球对超声的吸收作用。采用水热法制备亚微米级Fe3O4模板微球,通过改进的Stber方法对磁性Fe3O4粒子进行SiO2包覆,并用MPS化学试剂修饰所得复合微球,通过聚合反应得到PNIPAM@SiO2@Fe3O4磁性复合材料。对所获亚微米级磁性复合材料的结构和性能进行了表征,检测了该复合材料的超声波性能。结果表明:该亚微米级复合材料呈现球状核壳结构,具有良好的超顺磁性,且对超声波具有较好的吸收作用,因此该复合材料可以应用于吸波、降噪、减震等领域
近30年西北地区耕地生产力动态演变及能力评价
Dynamic evolution of cultivated land productivity and its capacity evaluation in Northwest China during 1982—2012

,杨延征,上官周平
- , 2015, DOI: 10.7606/j.issn.1000-7601.2015.03.35
Abstract: 为了明确西北地区耕地生产力及其动态演变过程,掌握该区在全国粮食生产中的整体水平,利用1982—2012年西北地区耕地生产力数据,结合GIS分析描述了该区近30年耕地生产力和耕地压力指数动态演变过程,及该区在全国粮食生产中的整体水平,结果表明:近30年来,西北地区耕地生产力呈现出小范围波动、连续上涨的发展趋势,从1982年的2078.28 kg·hm-2上升至2012年的5 643.75 kg·hm-2,翻了近3番,但其年均增长率不稳定,年际间变化幅度相对较大,在1996年到达历史最高水平23%;西北地区耕地生产力在全国的比重明显上升(由1982年的0.455上升到2012年的0.749),但又始终低于全国平均水平(耕地粮食生产力指数始终小于1),随着时间的推移,该区粮食生产中心主要向粮食生产能力较高的新疆和陕西地区集中;西北地区耕地压力指数在阶段性波动变化中呈现出略微减小趋势,耕地压力有所缓解,但其缓解幅度并不大,耕地压力级别始终处在Ⅱ级预警值(0.91~1.10)范围内。
In order to evaluate the dynamic evolution of cultivated land productivity in Northwest China and assess the overall level of grain production in the country, productivity data in cultivated land of Northwest China during 1982—2012 were analyzed using GIS software. The results showed that cultivated land productivity in northwest area displayed a fluctuating but constantly increasing tendency in a small scale, resulting a three times increase from 2078.28 kg·hm-2 in 1982 to 5643.75 kg·hm-2 in 2012. However, the average annual growth rate was not stable and the inter-annual variation remained large, reaching a historically high value of 23% in 1996. The cultivated land capacity in northwest area became increased significantly (from 0.455in 1982 to 0.749 in 2012), which, however, had always been lower than the national average level (relative index of cultivated land productivity was always less than 1). With time going, grain production centers in the area moved mainly to Xinjiang and Shaanxi that have higher grain production capacity. The pressure index of cultivated land in northwest region showed periodical fluctuations with a slightly decreasing trend, relieving cultivated land pressure to a mild level. The pressure level of cultivated land had always been at warning level II in a certain range(0.91~1.10).
西北五省(区)耕地质量等别差异性比较
Comparisons on variations in qualities of arable lands in northwestern China

,杨延征,上官周平
- , 2015, DOI: 10.16302/j.cnki.1000-7601.2015.02.038
Abstract: 为了明确西北地区耕地等别分布特征及在全国耕地等别中的整体水平,以西北5省(区)农用地分等国家级汇总成果为基础,分析了西北地区耕地等别数量特点、耕地等别空间分异特征和耕地质量的影响因素。结果表明:西北地区中、低等地分布广泛,面积比例高达93.04%,耕地平均等别比全国平均等别9.8等低2.1个等别;西北地区各自然质量等地和利用等地分布的总体趋势基本一致,高等地主要分布在陕西(60.82%和86.48%),中等地主要分布在新疆(50.99%和50.54%),低等地主要分布在甘肃和陕西(53.4%、31.76%和46.87%、26.31%),青海和宁夏耕地面积较小,且以中低等地为主;各经济等地分布略有不同,即高等地主要分布在新疆(85.12%),中等地主要分布在新疆和陕西(60.86%和26.98%),低等地主要分布在甘肃和陕西(48.95%和30.74%),青海省以低等地为主,宁夏以中低等地面积比例较大;西北地区耕地质量主要受到地貌结构、土壤条件和农田基本建设3类因素的影响,且各类影响因素在西北各省域内的分布差别主要决定于各省(区)主导因素的差异,从而进一步控制西北地区耕地质量的空间分布规律。
In order to evaluate the distribution characteristics of the arable lands in Northwest China and its status in the whole country, based on the accomplishments of cultivated land classification at the national level for the five provinces in Northwest China, the quantitative and grade and spatial distribution characteristics of the arable lands were analyzed in Northwest China, as well as the influential factors on land qualities. The results showed that medium and low grade lands were broadly distributed, up to 93.04% of the area. The average arable grade was 11.9, 2.1 lower than the national average level (9.8). The distribution of arable land natural quality and utilization grade were roughly the same in Northwest China. High-grade arable lands were mainly in Shaanxi, medium-grade arable lands were mainly in Xinjiang, and low-grade arable lands were mainly in Gansu and Shaanxi. Arable land area in Qinghai and Ningxia were small, majority of which was medium or low-grade. In addition, the distributions of arable land economic grade were slightly different. High-grade arable lands were mainly in Xinjiang, medium-grade arable lands were mainly in Xinjiang and Shaanxi, and low-grade arable lands were mainly in Gansu and Shaanxi. Qinghai had large area of low-grade arable lands, and Ningxia had large area of lower-grade lands. The arable land quality of Northwest China was mainly influenced by geomorphological structure, soil conditions and basic farmland constructions. Factors that influenced the variations in spatial distributions in different provinces were mainly determined by different dominant factors of the provinces, which further controlled the spatial distribution characteristics of the arable land quality in Northwest China.
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