Results 11 to 20 of about 1,464 (107)
Assessing the current state of ecological connectivity in a large marine protected area system
Conservation Biology, Volume 35, Issue 2, Page 699-710, April 2021., 2021 Abstract The establishment of marine protected areas (MPAs) is a critical step in ensuring the continued persistence of marine biodiversity. Although the area protected in MPAs is growing, the movement of individuals (or larvae) among MPAs, termed connectivity, has only recently been included as an objective of many MPAs.
Kelsey E. Roberts +3 more
wiley +1 more source
±1100kV直流SF6气体绝缘穿墙套管支柱绝缘子电场分布特性分析 [PDF]
全球能源互联网, 2019 特高压直流穿墙套管作为换流站中连接阀厅和直流场的唯一通道，是承载系统全电压、全电流的核心设备。作为换流站的核心设备，其安全稳定运行关系到整个系统的可靠性。中国某1100kV直流穿墙套管采用V型结构，由户内和户外两个空心复合绝缘子通过穿墙而过的气体绝缘管道连接而成，气体绝缘管道内部垂直安装两个支柱绝缘子。根据气固绝缘系统的非线性电导模型，考虑了气体内部载流子的产生、复合、迁移及扩散的物理过程，计算了1100kV穿墙套管内部气体绝缘管道的支柱绝缘子在直流电压下的电场分布 ...
刘鹏 +7 more
doaj +1 more source
Shuitu Baochi Xuebao, 2021 为探究土壤残膜量对膜孔灌肥液入渗土壤水氮运移特性的影响，通过室内土箱模拟试验设置0，90，180，360，720 kg/hm2的5个残膜量水平，分析不同残膜量下膜孔灌肥液入渗累积入渗量、湿润锋运移距离、湿润体特征和水氮分布规律。结果表明：残膜对膜孔灌肥液入渗具有阻渗作用，残膜土累积入渗量较无残膜土减少10.63%~30.77%，Kostiakov模型对残膜土单位膜孔面积累积入渗量与入渗时间有较好地拟合效果；入渗前30 min，不同残膜量的垂直湿润锋运移距离差异不显著，随着入渗时间推进 ...
刘大有 +6 more
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Zhejiang Daxue xuebao. Lixue ban, 2011 1-取代-2-羟氨苯并咪唑类化合物是1-取代-2-氨基苯并咪唑衍生物氧化代谢产生的具有强毒性的不稳定中间体.本文运用密度泛函理论(DFT)量子化学方法，计算得到了8种1-取代-2-羟氨苯并咪唑衍生物的电子结构性质.结果表明，取代基团的引入使咪唑环上C—N键长发生明显改变，N原子上负电荷减少；取代基团的引入对偶极矩、垂直电离势、垂直电子亲合能、化学势、电负性和亲电性等都有较为显著的影响，这些电子结构性质与化合物的毒性息息相关.通过计算得到了吸收光谱数据，取代基团的引入使垂直激发能变大，谐振子强度明显减小 ...
XIEHu-jun(谢湖均) +4 more
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Migration patterns of oil leakage from underground oil depots on coral islands and reefs, and its impact on freshwater lenses [PDF]
Amid the increasing scarcity of terrestrial resources, the vast resource potential of the marine environment has accelerated human exploration and exploitation of the ocean.
Gang YANG +3 more
core +1 more source
Shuitu Baochi Xuebao, 2003 用模拟土柱的方法对黄淮海平原主要土壤类型中硝态氮垂直运移的影响因素进行了研究。结果表明:在水分饱和条件下,硝态氮的垂直运移过程主要受土壤粘粒含量的影响,随着粘粒含量的增加硝态氮出流的时间推迟,硝态氮的穿透曲线的峰值变低、峰面分布变宽;在非饱和条件下硝态氮的穿透曲线变得不规则,有明显的拖尾现象,硝态氮运移的时间增长,穿透曲线变得平缓;示踪剂的流速对硝态氮运移有较大的影响,流速大的穿透曲线峰值高于流速小的穿透曲线峰值,且出流的时间和达到平衡的时间提前;不同价态阳离子由于带的电荷量不同,对硝态氮运移略有影响 ...
陈效民 邓建才 柯用春 张佳宝 朱安宁
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Research progress and future study of carbon emission reduction for UCG [PDF]
The integration of underground coal gasification (UCG) and carbon emission reduction is expected to become an excellent green energy technology during the transitional stage from the current to the arrival of carbon neutrality, and even play an important
Jun WANG +4 more
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Integrative Conservation, Volume 4, Issue 1, Page 71-84, March 2025.Gaoligong Mountain is home to a large number of rare and endangered species, but the effectiveness of conservation measures in the Gaoligong Mountain Nature Reserve remains uncertain. We predicted the potential distribution areas of 361 rare and endangered wild plants in southern Gaoligong Mountain under current and future climate change scenarios and ...
Yong‐Jing‐Wen Yang +3 more
wiley +1 more source
Shuitu Baochi Xuebao, 2020 为探究滴灌条件下水温与土温对覆砂土壤水热运移规律的影响，基于HYDRUS-2D构建了不同水土温度土壤水热运移数值模型，模拟分析了不同水土温度对覆砂土壤水分、温度动态变化的影响。结果表明：灌溉水温对土壤水热分布影响显著，随着温度升高，土壤湿润体内含水率减小，表现为35℃水温 < 20℃水温 < 5℃水温，灌溉水温对土壤剖面温度分布也有较大影响，表层0—15 cm范围内温度变化了5~10℃。相同水温条件下，随着土壤温度升高，土壤饱和导水率增大，湿润土体内体积含水率减小，表现为30℃土壤温度 < 15 ...
虎军宏 +3 more
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Shuitu Baochi Xuebao, 2008 针对西北等干旱地区土地次生盐渍化的问题,以室内试验为基础,测定盐碱土在不同滴灌施钙浓度下水盐运动过程,研究了不同施钙浓度对盐碱土土壤盐分运移和水分运动的影响。结果表明,不同施钙浓度的湿润锋水平、垂直最大运移距离与钙离子浓度之间均符合线性关系,湿润锋的水平、垂直运移距离与入渗时间之间符合幂函数关系,随着湿润锋水平、垂直湿润距离的增加,不同滴灌施钙浓度的土壤含盐量、钠离子含量均在不断增加,随着施钙浓度的增加,脱钠区深度系数增大,脱盐效果明显。
孙海燕, 王全九, 刘建军
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