Results 21 to 30 of about 19,312 (167)
, 1987 文献[3,4]表述了描述等离子CVD化学反应器流场的数学物理模型,并利用Patankar方法对冷热流场作了求解。本文在此基础上就影响反应器流场、温度场和浓度场的有关参数作了理论研究。所研究的问题有:冷热流场的差别,喷射环缝密度和主流旋转速度对流动的影响。所得结果清楚地表明:这些参数的选择对反应器的性能有着不同程度的影响 ...
朱清文, 赵国英
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Evaluating the empirical basis for threat attribution in the IUCN Red List
Conservation Biology, EarlyView.Abstract Understanding the impacts of different threats on species is key to successful conservation interventions and policies. The International Union for Conservation of Nature (IUCN) assesses threats to species, and the organization's Red List of Threatened Species is a key conservation tool.
Ena Humphries +5 more
wiley +1 more source
QSPR Study on the permeability of drugs across Caco-2 monolayer(药物对Caco-2单细胞层穿透性的QSPR研究)
Zhejiang Daxue xuebao. Lixue ban, 2009 Caco-2单细胞层用于模拟或预测体内小肠吸收均较剥离的小肠膜效果好.利用偏最小二乘分析方法研究Vol Surf参数与药物透过Caco-2单细胞层的渗透系数之间的定量结构-性质关系(QSPR),得到较好的结果(r2 = 0.95,q2=0.75).对其它类药物的预测结果表明,用结构不同的化合物所建立的模型对肽类药物以及同系物分子均有一定的预测能力,但是当分子的柔性键多,可能形成分子内氢键时,模型的预测能力大大下降.参数分析表明对Caco-2单细胞层渗透性高的药物分子必须具有合适的氢键给体和受体 ...
HUGui-xiang(胡桂香) +3 more
doaj +1 more source
CFD Modeling of Tubular Loop and Fluidized Bed Reactors for Propylene Polymerization [PDF]
, 2010 为消化吸收国外引进的丙烯聚合装置，并理论指导国内丙烯聚合反应器的自行设计与放大工作，本论文以中试规模的Spheripol-II工艺的丙烯聚合环管和流化床反应器为研究对象，运用计算流体力学方法及Fluent软件，分别建立环管与流化床反应器的稳态与动态欧拉双流体模型。利用上述建立的模型分析各反应器内部的传递规律。主要研究内容如下： 1、对于环管反应器，首先通过三维CAD软件Pro/Engineer绘出轴流泵与环管的三维模型，在Gambit软件中划分该系统的网格。在此基础上，建立了环管反应器内液-固二相的 ...
施德？
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Using incentive payments to promote human–carnivore coexistence
Conservation Biology, EarlyView.Abstract For many large carnivores, minimizing the financial burden they impose on local people is critical to their conservation. Incentive‐based programs that provide people with financial benefits for taking pro‐conservation actions or achieving conservation goals are a promising tool for promoting human–carnivore coexistence. Although the number of
Adam Pekor +9 more
wiley +1 more source
Gaoya dianqi, 2018 由于SF6气体温室效应显著,CO2气体作为目前具有潜力环保型SF6替代气体之一,以CO2气体作为绝缘和灭弧介质的断路器已经得到应用。实际上,喷口材料烧蚀将导致PTFE蒸汽作为杂质影响电弧等离子体的物性参数从而影响断路器的开断性能。为了建立物理模型研究和优化断路器开断性能,必须首先确定电弧等离子体物性参数。因此文中研究了0.6 MPa下温度区间为300～30 000 K时的CO2-PTFE电弧等离子体物性参数。首先基于最小Gibbs自由能法确定了电弧等弧等离子体粒子组分 ...
韩桂全 +5 more
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Shuitu Baochi Xuebao, 2020 为探讨运用数学模型进行生物滞留池构型和参数优化设计的方法，以RECARGA模型为工具，评估生物滞留池的设计参数和结构改变的径流水文调节效果，定量分析设计参数与水文性能的关系，从而确定适宜的生物滞留池配置方法。结果表明：设施底层土壤导水率是整个滞留系统水文性能的限制因素，年雨水滞留量随土壤导水率的增加呈显著的对数函数增加。雨水滞留率与设施表面积比率有着显著的对数函数关系。雨水滞留量与蓄水层厚度呈显著的幂函数关系，而与根系层和贮水层厚度呈良好的线性关系；考虑排水因素，蓄水层深度建议不宜大于15 cm ...
涂安国, 李英, 莫明浩, 聂小飞
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, 2016 A geothermal well in Ganzi was chosen for the study. To provide a reference for the design and construc?tion of a geothermal plant, power generation techniques were selected and the thermodynamic process was calculat?ed based on cold and heat source ...
卜宪标 +3 more
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Conservation Biology, EarlyView.Abstract Constructed value of information (CVoI) is an expert elicitation decision‐analytic tool used to prioritize sources of uncertainty based on their potential to improve decision outcomes if resolved. Despite increased application of CVoI, the robustness of CVoI prioritization of sources of uncertainty relative to differences in expert elicitation
Kristin P. Davis +7 more
wiley +1 more source
Gaoya dianqi, 2016 开关设备（例如高压SF6断路器）触头表面产生的铜金属蒸气会改变电弧等离子体的物理化学特性。因此在建立考虑金属烧蚀的流体仿真模型之前,需要确定含有金属蒸气的电弧等离子体的性质。文中基于吉布斯自由能最小化原理和Chapman-Enskog理论,计算了SF6-Cu混合气体电弧在0.6 MPa压强下、温度区间为30030 000 K时的物性参数,包括平衡态粒子组分、统计热力学参数、输运系数和混合扩散系数,着重分析了铜蒸气浓度（最大90%）对上述物性参数的影响。结果表明少量的铜对物性参数无明显影响 ...
袁端磊 +5 more
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