Results 21 to 30 of about 1,437,872 (201)
Gaoya dianqi, 2011 针对40.5kV新型磁力机构工作原理及其运动特点,进行了多场耦合的静态和动态特性仿真研究。首先,建立磁力操动机构的有限元模型,利用Maxwell软件对磁力机构的静态特性进行仿真;其次,根据电压平衡方程和达朗贝尔运动方程,在静态仿真基础上采用ADAMS和MATLAB建立40.5kV磁力机构SF6断路器运动模型,对磁力机构的动铁心、SF6断路器触头运动特性进行了仿真研究。最后,分析了磁力机构运动特性对SF6断路器性能的影响,为新型磁力机构在中压SF6断路器中应用提供了一定理论基础。
茹晶晶 +5 more
doaj
Advancing conservation breeding programs for marine invertebrates
Conservation Biology, EarlyView.Abstract In the face of ecosystem change and biodiversity loss caused by climate change and other stressors, conservation breeding, or captive breeding, with the aim of reintroduction for wild population recovery, is an emerging tool for preventing species’ extinction and rehabilitating ecosystems.
Elora H. López‐Nandam +3 more
wiley +1 more source
Gaoya dianqi, 2017 针对在设计真空断路器弹簧操动机构凸轮轮廓线的过程中,依靠经验或者反复试验的方法设计出的凸轮轮廓线存在无法准确匹配负载特性的缺陷,采用一种负反馈优化设计方法。首先,根据负载特性推导出动力特性;其次,通过动力特性倒推出凸轮转角,进而计算出凸轮轮廓线;然后,根据凸轮呈现的合闸动力特性再次验证并修正负载特性,保证分合闸速度;最终,通过设计验证证明了使用该方法设计的凸轮能够使得动力特性准确匹配负载特性,并保证断路器可靠合闸。
赵玉芝 +5 more
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Taxonomic and functional diversity of urban bees of the world
Conservation Biology, EarlyView.Abstract Bees play a pivotal role in terrestrial environments. Urbanization can affect these organisms and the ecosystem services they provide. However, knowledge of the global diversity of urban bees is limited. Thus, we summarized data on urban bee species identities and occurrences; compared distributions of all bees with those found in urban ...
João C. F. Cardoso +10 more
wiley +1 more source
Gongye shui chuli, 2014 通过活性污泥对阿特拉津的等温吸附和动力学吸附试验，研究了活性污泥对阿特拉津的吸附特性。结果表明：活性污泥对阿特拉津具有一定的吸附能力，且加入HgCl后吸附效果较好，原因是抑制微生物活性的污泥，化学稳定性好，吸附能力也相应加强；另外，硝化污泥对阿特拉津的吸附能力要好于普通活性污泥；伪二级动力学方程和颗粒内扩散方程能更好地拟合活性污泥对阿特拉津的动力学吸附特征，表明吸附是化学吸附和颗粒扩散共同作用的结果。
王红娟 +6 more
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Gaoya dianqi, 2022 电磁斥力机构由于其分闸速度快，分闸时间短和分闸时间分散性低等优势，配备于快速真空开关，可极大地压缩电网故障的切除时间，当前受到了众多研究者的关注。文中的目的是研究配于快速真空开关的电磁斥力机构的暂态动力学特性。文中提出了一种新型的全耦合仿真方法，该方法耦合了柔体动力学模块、外电路模块、运动方程、多体动力学模块、瞬变电磁场和疲劳分析模块的求解过程，可对电磁斥力机构的暂态动力学特性进行全面评估。通过仿真计算了各零部件在分合闸过程中的速度、行程曲线、放电电流、洛伦兹力和应力应变等动态特性 ...
王蕾 +7 more
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Informal supply chains of wild meat from rural Amazonia and food security in an urban center
Conservation Biology, EarlyView.Abstract Iquitos, the most populated city in the Peruvian Amazon, is a hub in the regional supply chain of wild meat and supplies urban consumers. Studies on wild meat consumption have focused primarily on markets, limiting the scope of species considered to those that are economically valuable and potential inferences from those data.
Fiorella Briceño Huerta +3 more
wiley +1 more source
, 1994 本文提出了一个从正常固结海底土在等幅周期载荷作用下的不排水动力特性预测正常固结海底土在其它条件下的动力特性的方法。其中;考虑了非均一的应力水平及排水条件等因素的影响;用该方法对一种取自北部湾的海洋粉质土的动力特性进行预测 ...
黄锋, 赵京, 楼志刚
core
Gaoya dianqi, 2023 高压自能式SF6断路器单向阀、回气阀和泄压阀的运动特性对灭弧室气流场计算结果的准确性具有重要影响。基于3个阀片实际的运动规律，运用牛顿第二定律，建立阀片运动的数学模型，并结合真实气体物性参数，对自能式SF6断路器灭弧室冷态气流场进行仿真，准确获得了3个阀片的运动特性，同时分析了3个阀片的受力特性及阀片周围的压力分布。研究表明，空载情况下，单向阀将对拉杆产生相对运动，这是引起单向阀由闭合到开启状态变化的主要原因，而回气阀移动的主要原因是压气室压力的建立 ...
赵伟涛 +4 more
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Assessing differences among elasmobranch nurseries to aid conservation based on a genomics framework
Conservation Biology, EarlyView.Abstract Elasmobranch nurseries often differ in environmental conditions, demographics, and use patterns. These differences affect the distribution of genetic variation among nurseries. However, conservation and management strategies often fail to account for such differences because they are difficult to characterize.
Dominic G. Swift +8 more
wiley +1 more source