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Search Results: 1 - 10 of 71772 matches for " 葛国勤 "
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注入原子相干对双模纠缠的影响
崔海生,张波,
量子电子学报 , 2014,
Abstract: 在梯形三能级原子系统中,用段路明等人提出的纠缠判据讨论了注入原子相干对双模腔场纠缠的影响。结果表明,只有在原子相干存在时,双模腔场的纠缠态才能产生。在增益系数一定的情况下,双模腔场的纠缠度随着失谐量的变大先变大然后变小。在失谐量一定的情况下,双模腔场的纠缠度随着增益系数的变大而变大。在失谐量为零的情况下,不管原子相干是否存在,双模腔场的纠缠态都不能被产生。
高温涂层及金属的半球向全热发射率测定装置
新石,,,倪鹤林,徐洪福,金璐
工程热物理学报 , 1982,
Abstract: 本文介绍了涂层及金属在1000K—1800K温度范围内的半球向全热发射率测定装置,给出了几种高温涂层的半球向全热发射率数据。对测试误差进行了分析,实验表明,本文介绍的装置操作方便,性能稳定,测得的数据有很好的重复性。
基于时驱硬球算法与格子玻尔兹曼方法的颗粒流体系统直接数值模拟
,王利民,王小伟,,
科学通报 , 2011, DOI: 10.1360/972010-1687
Abstract: 实现了一种直接数值模拟颗粒流体系统的耦合算法,颗粒间相互作用由时驱硬球算法描述,而流体的控制方程采用格子玻尔兹曼方法求解,流固耦合用浸入运动边界法实现.该方法使用欧拉网格求解流场,拉格朗日网格跟踪颗粒,避免了非结构化贴体网格方法需要重新划分网格的问题.通过模拟两个圆形颗粒在黏性流体中的沉降过程,成功地复现了经典的Drafting-Kissing-Tumbling(DKT)过程,验证了耦合算法的有效性.
江西生态旅游的可持续发展研究
Research on the Sustainable Development of Eco-Tourism in Jiangxi Province
 [PDF]

马艳芹,
International Journal of Ecology (IJE) , 2014, DOI: 10.12677/IJE.2014.31002
Abstract:
江西发展生态旅游具有重要的环境意义、经济意义和社会意义。江西生态旅游资源十分丰富。近十多年来,江西生态旅游发展取得了显著成效,但同时也存在诸多突出问题,如规划滞后、管理混乱、开发无序、破坏严重和宣传不力等。为实现江西生态旅游的可持续发展,作者提出应采取如下策略:1) 制定严格、科学的景区发展规划;2) 进行生态旅游管理体制、机制的改革与创新,实施多元化旅游管理机制;3) 征收旅游资源使用费,促进江西省生态旅游的可持续发展;4) 突出地域特色,设计旅游产品,开发生态旅游精品;5) 扩大宣传,提高旅游者爱护环境文明旅游的意识。
The development of eco-tourism in Jiangxi has an important environmental, economic and social significance. The eco-tourism resources in Jiangxiare very rich. Over the past decade, the development of eco-tourism in Jiangxi has made remarkable achievements, but there are still many outstanding issues, such as planning is still lagging, the management is confused, the development is disordered, the environment is seriously damaged and the publicity is ineffective. To achieve the sustainable development of eco-tourism in Jiangxi, the authors proposed that the following strategies should be taken: 1) ensure area development planning rigorous and scientific; 2) reform and innovate the system and mechanism in eco-tourism management, implement diversified tourism management unit; 3) levy user fees of tourism resources to promote the sustainable development of eco-tourism in Jiangxi Province; 4) highlight the regional characteristics, design tourism products, develop eco-tourism boutique; 5) expand the publicity and improve the tourists’ awareness of caring for the environment and cultural tourism.
中国鄱阳湖湖泊生态学研究
Ecological Research on Poyang Lake in Jiangxi Province, China
 [PDF]

周泉,
International Journal of Ecology (IJE) , 2013, DOI: 10.12677/IJE.2013.23004
Abstract:

鄱阳湖是江西人民的“母亲湖”,是我国最大的淡水湖,是世界生命湖泊网中的重要成员,自鄱阳湖生态经济区建设上升为国家战略之后,对鄱阳湖的湖泊生态研究显得越来越重要。本文在调查研究和文献阅读的基础上,对鄱阳湖湖泊生态学的发展以及研究内容进行简要分析和总结,为促进鄱阳湖湖泊生态学更好更快地发展提供参考资料。目前鄱阳湖湖泊生态学的研究主要集中在以下几个方面——鄱阳湖气候变化研究、鄱阳湖土壤生态研究、鄱阳湖水体生态研究、鄱阳湖生物多样性研究、鄱阳湖景观生态研究以及鄱阳湖生态修复研究等,在今后的研究中需要加强对鄱阳湖生物多样性、景观生态和生态修复的研究。

Poyang Lake is Jiangxi people’s “mother lake”, China’s largest freshwater lake, and the important member in the lake net of the world’s life. Since the construction of Poyang Lake ecological economic zone rose to national strategy, lake ecological research of Poyang Lake has become more and more important. In this paper, on the basis of the investigation research and literature reading, a brief analysis and summary of the development and research of lake ecology of Poyang Lake have been made, so as to provide some references for promoting lake ecology of Poyang Lake better and faster development in the future. It is found that, at present, the research mainly focused on the following aspects: climate change research, soil ecological research, water ecological research, biodiversity research, landscape ecological research, ecological restoration research, etc. We need to strengthen the research of biodiversity, landscape ecology and ecological restoration in the future.

?“全鱼”转生长激素基因黄颗鱼首建者的建立*
家春?,宋伟董张及,许志强,鲍洁,,潘建林,杨家新,赵庆顺**
南京大学学报(自然科学) , 2013, DOI: 10.13232/j.cnki.jnju.2013.01.015
Abstract: 黄颡鱼(pelteobagrusfulvidraco)是一种重要的淡水名优经济角鱼类,然而较小的体型和较慢的生长速率极大地降低了它的经济价值.为获得大规格且快速生长的黄颖角,开展了转生长激素基因黄颖角的研究.运用rt-pcr和race-pcr技术,克降了黄颖角生长激素基因的603bp(碱基对)的编码序列和485bp,的3’-utr(非翻译区)序列.通过重叠pcr和限制性内切酶酶切连接,组建了一个长为2105bp的“全鱼”转生长激素基因构件,该构件含1017bp的黄颡鱼β-肌动蛋白近端启动子、603bp的生长激素基因编码序列和485bp,的3’-utr序列.采用显微注射将转生长激素基因构件导入黄颖角受精卵,从301尾由注射肛胎发育而来的黄颖角中共筛选获得40尾转生长激素基因黄颖角首建者.成功地建立了黄颡鱼基因组改造的技术平台,为黄颡鱼的基因工程育种奠定了基础.
面向浙江地方经济创办制药工程专业人才培养模式初探
刘文洪,何洁,,万海同,丁兴红,赵伟春,陈京,,立军,郭莹
中国中医药信息杂志 , 2008,
Abstract:
中国雾霾天气的成因、危害及其防治措施
Cause, Hazard and Control Measures of Hazy Weather in China
 [PDF]

孙丹平,
Advances in Environmental Protection (AEP) , 2014, DOI: 10.12677/AEP.2014.44015
Abstract:
近期,中国多地被雾霾笼罩,空气污染指数不断攀升,中国中东部地区连续发生了多次中度、重度、极重度雾霾天气。环保部门的数据则显示,从东北到西北,从华北到中部乃至黄淮、江南地区,都出现了大范围的重度和严重污染,导致了人们的生活质量逐渐下降。可见雾霾已经成为严重影响人类生存的迫在眉睫的问题。本文从雾霾天气的概念、分级和组成成分,成因及危害进行分析与探讨,并提出相应的雾霾防治措施,为进一步认识雾霾和改善环境空气质量提供参考价值。
Recently, our country is shrouded by hazy weather. The air pollution index continues rising. Re-peatedly, moderate, severe and extremely severe hazy weather appeared in the central eastern part of China. Meanwhile, the data of the environmental protection department show that: from the northeast to the northwest, from north China to central and Huanghuai, Jiangnan region, there was a wide range of heavy and serious pollution, leading to a fall in the quality of people's life gradually. So, hazy weather has become a serious and urgent problem causing impact on human’s survival. This article analyzes and discusses the concepts, classification, components, causes and hazard of hazy weather. Corresponding measures for prevention and control of the hazy weather are mentioned in order to provide the reference value for further understanding the rules of the hazy weather and improving the air quality of the environment.
红椿沟泥石流治理工程防灾效果数值模拟研究
The Study on Numerical Simulation of Debris Flow Disaster Prevention Engineering Effect in Hongchun Gully, Sichuan Province
 [PDF]

, 孙书
Advances in Geosciences (AG) , 2016, DOI: 10.12677/AG.2016.63018
Abstract: 本文研究区为红椿沟流域,位于2008年5.12汶川大地震震中映秀镇的东北侧,全流域面积约为5.35 km2,红椿沟为岷江左岸一级支沟,在形态特征上呈现长条状扇形特征,研究区海拔最高点为沟源处望乡石高程为2169.2 m,最低点为沟口,高程881 m,全流域的相对高程差达到1288.2 m。流域主沟长约3.6 km,纵坡率约为357.8‰。研究中发现,红椿沟治理工程竣工后,发生了两次设计工况下的泥石流和一次超标暴雨工况下的泥石流,为合理判断治理工程数值模拟的防灾效果,将模拟结果与工程实际运行效果监测数据相比较,故本文在数值模拟时,选择具有代表性的2种不同频率的重现周期(p = 2%, p = 1%)进行泥石流暴发模拟,同时根据不同区段的监测数据,本文在模拟过程中通过合理设置集水点位置,将治理工程分段进行了防治效果模拟。红椿沟泥石流治理工程在设计工况下(p = 2%)的数值模拟中防灾效果显著,在超标暴雨工况下(p = 1%)的数值模拟中抗灾效果显著。
The study area Hongchun basin is located in the northeast side of Yingxiu Town, which is the 2008.5.12 Wenchuan earthquake epicenter. It is also located on the left bank of the Minjiang River. The ditch and valley pattern is approximate a sector and its area is 5.35 km2. The highest point is located in Xin Dian Zi Gou’s source; the elevation is 2162.2 m; Mizoguchi and Minjiang River in-tersection height is 881 m; relative elevation is 1288.2 m; channel longitudinal is 3.6 km; average longitudinal gradient of gully is 357.8 per thousand. It was found in the study that after the Hong-chun gully disaster prevention project completed, it has broken twice debris flow in the design condition and once debris flow exceeding the design condition. In order to reasonably judge the effect of the project, we compared the simulation results with the actual operation results of the project. So in the numerical simulation of this article, we selected 2 representative recurrence pe-riods of frequencies (p = 2%, p = 1%) to simulate. At the same time, according to the monitoring data of different sections and by setting up reasonable water gathering point positions in the si-mulation process, the disaster prevention project is divided into several sections for numerical simulation in this article. The numerical simulation results show that, in the design condition (p = 2%), the Hongchun gully disaster prevention engineering effect is remarkable, and over the design condition (p = 1%) the effect is also good.
ω-羟基烷基键合相高效液体色谱填料的研究Ⅰ.ω-羟基烷基堆积硅球的制备和性能考察
,刘维
分析化学 , 1985,
Abstract: 化学键合固定相是高效液体柱色谱技术发展的重大成就。虽然历史很短,但已引起了人们的注意[1]。由于(ω-三甲硅氧基)-烷基-三氯代硅烷,Cl3-Si-(CH2)n-O-Si-(CH3)3分子中含有潜在的羟基,该类化合物又具有-Si-Cl活性基团,因此曾有人[2]用它们处理薄壳型硅胶(CorasilⅡ)和无定形全多孔型硅胶(MerckosorbSI60)改性。在本实验中,我们选用堆积硅球为担体,试制了碳链长度不同的ω-羟基烷基堆积硅球用作高效液体柱色谱的填料,并对其性能进行了考察。
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