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Search Results: 1 - 10 of 329498 matches for " 王康莉 "
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刺五加果实及种子内源萌发抑制物质活性的研究
赵敏,,
中国中药杂志 , 2001,
Abstract: 目的:通过对刺五加果实及种子内源萌发抑制物质的研究,探讨了刺五加种子休眠的原因。方法:制备刺五加果实的各部分及种子的粗提物,并测定其活性;制备刺五加中果皮的乙醚提取液并进行纸层析,然后测定各区段的活性。结果和结论:首次证明了刺五加果实及其外果皮、中果皮、种子中均含有一定活性的内源抑制物质。外果皮、中果皮、种子中所含的内源抑制物质对白菜种子萌发的抑制活性高于对白菜幼根生长抑制活性,刺五加中果皮乙醚提取物纸层析在Rf0.l区段对白菜种子萌发和白菜幼根生长有最强抑制,刺五加果实粗提物能抑制小麦种子萌发过程中α-淀粉酶活性,且在一定浓度范围内对小麦种子萌发及幼苗生长也有明显抑制作用,随粗提物浓度增大抑制活性明显增强。刺五加果实和种子中活性较高的内源抑制物质与刺五加种子的深沉休眠特性密切相关。
中扬子地台早奥陶纪和华南盆地泥盆纪生物礁的纵向对比
The Vertical Comparison between the Early Ordovician Reefs in Middle Yangtze Platform and the Devonian Reefs in South China Basin
 [PDF]

汪严, 肖传桃, 刘磊, 刘宇航, , 葛婧艳
Advances in Geosciences (AG) , 2016, DOI: 10.12677/AG.2016.64030
Abstract: 从上个世纪初以来,生物礁因为其是油气储存得天独厚的场所而不断得到研究者的重视,因此从刚开始的生物礁的定义、分类以及控制因素到后来的时空分布关系等方面均有不少成果问世。由于生物礁特殊的生存环境(适宜的温度、充足的阳光、纯净的水质);故同一地区在不同地质时期因为所发生的构造运动不同,导致环境改变,从而造成生物礁的种类和数量有很大的区别。本文主要是从生物礁的基本概况(包括主要造礁生物和附礁生物特征)、沉积地质条件(大地构造条件和岩相古地理条件),生物礁的主控因素(古气候、古环境、海平面等)、找油意义这几个方面来对中扬子地台早奥陶纪和华南盆地泥盆纪生物礁进行纵向对比,揭示了这两个时期生物礁发育的差异性和相似性特点。
Since the beginning of the last century, reefs are paid for increasing attention by researchers as it owns unique advantages of storing oil and gas. And there are a lot of achievements in the definition, classification and control factors of reefs at first and its spatial and temporal distribution later. Considering the special living environment, like the optimum temperature, the opulent sunshine and pure water, the same area will have a big difference in the types and quantity of reefs that is caused by occurred tectonic movement which causes the change of environment. This thesis conducts comparison between the Early Ordovician reefs in Middle Yangtze Platform and the Devonian reefs in South China Basin vertically from the basic introduction, including the feature of reef-forming organisms and reef-inserted organisms, deposit geological condition, including geotectonic conditions and lithofacies palaeogeography conditions, the key control factors of organic reef containing the paleoclimate, the paleoenvironment, the sea level and the meaning of exploration of oil, which reveals the differences and similarities of reefs development in these two periods.
MSMPR连续结晶器的多定态
尹秋响,,
化工学报 , 1997,
Abstract: 对混合悬浮混合排料(MSMPR)连续结晶器的定态方程组进行了剖析,应用非线性方程组的延拓求解法,求得了定态方程组的分岔图,即MSMPR连续结晶器状态参数与操作参数的依赖关系.利用分岔理论对MSMPR连续结晶过程的定态数目及相应的参数范围进行了预测,导出了连续结晶过程存在多定态或唯一定态的判据。该判据仅与过程的动力学参数和操作参数有关,而与过程的状态参数无关。最后应用Routh-Hurwitz准则,确定了连续结晶过程各定态的稳定性。
青霉素亚砜结晶生长与成核动力学
井丁丁,张美景,,
化工学报 , 2014, DOI: 10.3969/j.issn.0438-1157.2014.01.023
Abstract: 利用Mydlarz和Jones模型(MJ2),对乙酸丁酯中青霉素亚砜的成核与生长动力学进行研究。通过矩量法对MJ2模型进行处理后,利用晶体产品的粒度分布计算得到青霉素亚砜的生长速率与成核速率,然后利用最小二乘法拟合回归求解出成核与生长动力学方程参数。通过实验设计考察了过饱和度、温度与搅拌速度对青霉素亚砜晶体成核和生长过程的影响。研究表明青霉素亚砜晶体生长速率随过饱和度比的增加呈现指数型增长,确定青霉素亚砜晶体生长属于晶体表面生长控制过程。由于高速搅拌会增加青霉素亚砜晶体的破碎,促进了二次成核过程,随着搅拌速度的增加,晶体生长速率出现小幅下滑,而成核速率则明显升高。青霉素亚砜成核与生长动力学研究将有助于工业生产过程优化。
铜片上水热法制备纳米Cu2S薄膜及光吸收性能
Characterization and Optical Absorption Property of Cu2S Nano-Films Prepared by Hydrothermal Method on Cu Foil
 [PDF]

张朔, 刘劲松, 李子全, 陈建, 丛孟启, 许奇, 丁滔, 春花, 高雪琴,
Hans Journal of Nanotechnology (NAT) , 2012, DOI: 10.12677/nat.2012.21002
Abstract:
采用水热法以硫代乙酰胺为硫源在铜片上沉积了Cu2S纳米薄膜,研究了添加剂种类对产物结构、形貌及紫外–可见光吸收性能的影响。X射线衍射仪(XRD)、场发射扫描电镜(FE-SEM)和红外光谱(IR)测试表明,产物为正交结构Cu2S,添加剂影响着产物的结晶及形貌。机理分析显示,在水热条件下添加剂以不同的方式参与了薄膜的形成过程。紫外–可见(UV-vis)光吸收性能测试及直接带隙计算表明,与Cu2S本体相比,所得薄膜带隙出现了不同程度的蓝移,这归因于样品的量子限制效应影响大于库仑项的影响。
Cu2S nano-films were synthesized on copper foil with TAA as sulfur sources by hydrothermal method. The effect of the different additions on structures, morphology and UV-vis absorption property of the films has been studied by X-Ray Diffraction (XRD), Scanning Electron Microscope (FESEM) and Infrared (IR) spectra and UV-vis absorption spectroscopy. The results show that the crystallinity and morphology of the Cu2S with orthogonal structure depended on the additions. The formation of the films was thought to come from the interaction between the additions and the reactants under the hydrothermal conditions. The UV-vis absorption spectra and the (αhν)2-hν curves suggest that the calculated band gap values indicated the distinct blue shift compared to that of the bulk Cu2S, which is attributed to the stronger quantum confinement effects than the Coulomb term.
He离子辐照金属钨引入缺陷的微结构研究
Study on Microstructure of He+-irradiation Induced Defects in Tungsten

,,邓爱红,,,,,卢晓波,,
- , 2016,
Abstract: 采用能量为100keV的He离子在室温下辐照金属钨,辐照注量范围为1.4×1017-3.5×1017/cm2,辐照后对样品进行了1100℃退火处理。利用X射线衍射、慢正电子多普勒展宽和扫描电镜技术研究了钨中He离子辐照引入的缺陷和注量之间的关系。研究结果表明辐照并退火后材料内部晶面间距增大,空位型缺陷浓度或尺寸随辐照注量的升高而增大,而高注量辐照的样品表面晶粒间连接疏松并存在孔隙,钨表层可能生成了大尺寸的He空位复合体或He泡。
The samples of tungsten were irradiated by 100keV helium ions at room temperature with different fluences ranging from 1.4×1017-3.5×1017/cm2 and then annealed at 1100℃. The interaction of helium-related defects with helium fluence was studied by means of X-ray diffraction (XRD), slow positron beam analysis (SPBA) and scanning electron microscope (SEM). The results show that the distance of crystal plane in tungsten increase after implantation. The concentration or/and size of the formed open-volume defects increase with the increase of irradiation fluence. The intergranular loose connections and voids on the surface of the sample, which were irradiated by the highest fluence of ions, reveal that there are vacancy-helium complexes or He bubbles with big size in the sample
溶液共沸法直接合成较高分子量的聚乳酸
,唐颂超,庆海,潘泳,婷兰
华东理工大学学报 , 2006,
Abstract: 采用溶液共沸法直接缩聚制备聚乳酸。探讨了复合催化剂、溶剂用量、反应时间及反应装置对聚乳酸相对分子质量的影响。结果表明:以乳酸质量分数w=0.01的复合催化剂(其中氯化亚锡与对甲苯磺酸质量比为1∶1)为催化剂,溶剂与乳酸的体积比为0.75∶1.00,在氮气氛保护下反应35h左右,能得到重均分子量为6.6×104的聚乳酸。
愈创木酚甘油醚晶习的影响因素
,姜海洋,刘利军,
天津大学学报(自然科学与工程技术版) , 2007,
Abstract: 通过改变溶剂、过饱和度以及原料杂质3个条件,得到了愈创木酚甘油醚的不同的晶习.利用扫描电子显微镜对所得到的晶体进行了测定,从而确定了溶剂、过饱和度和杂质对愈创木酚甘油醚晶习的影响.研究结果表明,它们主要通过影响各个晶面的生长速率来改变晶习.当改变溶剂和初始过饱和度时(110)面和(110)面之间的晶棱也随之改变甚至消失.随着过程过饱和度的减少晶体生长沿z轴方向趋于长度增加,并且晶体的(001)面和(001)面由四边形向六边形发展.没有杂质时晶体的晶习为长方体.
A Model Based on Genetic Programming for Credit Risk Assesment in Commercial Banks
基于遗传规划方法的商业银行信用风险评估模型

WANG Chun,|feng,KANG Li,
春峰
,

系统工程理论与实践 , 2001,
Abstract: In this paper, a model based on genetic programming is presented to credit risk assessment in commercial banks. Empirical results show that genetic programming model is more advantageous than traditional statistical models, neural network models and decision tree models in prediction accuracy and robustness.
后掠风力机叶片气动性能数值模拟
李媛,,樊小,建录,赵萍
工程热物理学报 , 2011,
Abstract: 采用商用软件FINETM/Turbo,以2.5MW风力机DF90风轮叶片为原型,在确认数值方法的基础上,将中叶展以上做后掠变型,进行三维定常数值模拟研究,讨论了后掠叶型对叶片气动特性的影响,并提出了一种定义后掠叶片静压系数的方法。
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