Results 31 to 40 of about 37,682 (204)
鄂尔多斯盆地姬塬地区长6 储层矿物含量与孔隙度的线性关系 [PDF]
, 2019 矿物含量是影响储层物性的重要因素之一。为了较全面地分析不同类型矿物含量对储层孔隙度的影响，以鄂尔多斯盆地姬塬地区长6 砂岩储层为例，探索性地运用多元逐步线性回归法分析了石英含量（x1）、长石含量（x2）、岩屑含量（x3）、绿泥石含量（x4）、伊利石含量（x5）、高岭石含量（x6）、硅质含量（x7）以及铁方解石含量（x8）与孔隙度（y）的关系，建立了矿物含量（xi）与孔隙度（y）之间的回归模型：y = 21.131-0.086 x2-0.113 x3-0.554 x4-0.370 x5-0.199 x6 ...
李小燕
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Scenarios and strategies for future‐proofing ecosystem management under climatic novelty
Conservation Biology, EarlyView.Abstract Climate change is driving unprecedented declines in dominant, habitat‐forming foundation species across marine and terrestrial ecosystems globally. As climatic novelty becomes the norm, ecosystem reassembly will become increasingly common. Predicting and understanding these transitions, and their implications for future ecosystem functioning ...
Lauren T. Toth +14 more
wiley +1 more source
Study on Corner-Fed Cavity-Backed Slot Dual-Polarized Antennas [PDF]
, 2015 为了在2.4GHz频段WLAN中实现具有方向性辐射的MIMO技术，采用背腔环形缝隙结构辐射元，通过倒置正交微带线激励，设计具有一定方向性的正交双极化天线结构。为提高端口间的隔离度和辐射场的极化纯度，在馈线正对的另一侧共面加载尺寸完全一致的接地或不接地导体带条。在此基础上，采用角馈的方法以期进一步改善天线的性能，并对各种可能天线形态进行对比分析。具体内容如下。 （1）对于边馈情形（即馈线位置垂直平分矩形导体腔表面的直角边），可以发现，没有加载导体条时，较佳隔离度对应的频带要高于阻抗工作频带，且相隔距离较大。
谢昇
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Perceived costs as drivers of wildlife management preferences in rural Tanzanian communities
Conservation Biology, EarlyView.Abstract Effectively managing human–wildlife interactions is crucial for fostering coexistence on shared landscapes. Management options are most effective when aligned with the preferences of people directly affected by wildlife, yet little is known about how socioecological factors influence these preferences.
Christian Kiffner +10 more
wiley +1 more source
Dizhen xuebao, 2018 在我国大陆广泛搜集到的45个地震序列的基础上，首先利用最大似然估计法计算出不同样本量地震序列的变异系数值，然后与其对应的断层源参数作相关性分析，并对具有不同样本量地震序列中的变异系数值进行标准化处理，进而计算得到一个通用的变异系数值（αc=0.37）。相关分析结果显示变异系数值与断层的长度和滑移速率呈负相关，在此基础上本文对通用变异系数值（αc=0.37）的应用进行了分析，通过对αc进行一倍标准差运算得到3个变异系数值（0.21，0.37，0.53），分别适用于特征性具有明显差异的活动断层.
Chun Hui +4 more
doaj +1 more source
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
Shuitu Baochi Xuebao, 2021 干旱荒漠地区地下水补给是地表植被水分消耗的主要补给源，地下水埋深与植被指数（NDVI）关系密切。针对植被指数与地下水埋深响应关系研究的不足，分析了基于河套灌区解放闸灌域植被指数（NDVI）与地下水埋深（H）的定量关系。采用2016年3—9月的10个时相的landsat8遥感影像数据与同时期的57眼地下水埋深观测数据，经NDVI遥感提取与地下水埋深（H）的地统计分析，建立NDVI与H的时空相关关系，并做显著性检验与密切程度的划分，进一步分析不同地下水埋深分区下H与NDVI的关系。结果表明 ...
郑倩 +6 more
doaj
西沙珊瑚鍶溫度計: 便捷高精度海洋古水溫代用指標 [PDF]
, 2001 Strontium concentrations in modem Porites coral from XishaIslands were determined by precise thermal ionization mass spectrometry. The coral skeleton grew in the period from 1976 to 1994.
Lee, T, Nie, BF, Sun, M, Sun, Y
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Characteristics of macrobenthic communities in the estuary of Dagujia River and its adjacent water areas in Yantai, Shandong [PDF]
, 2016 为了解烟台大沽夹河河口及邻近海域大型底栖动物群落特征及受干扰情况,于2012年9月在上述区域设置12个采样点进行大型底栖动物群落调查和分析。对采集的生物样品进行物种鉴定、计数和称重,利用生物统计软件PRIMER计算优势度指数(Y)、Shannon-Wiener多样性指数(H')、Margalef丰富度指数(D)和Pielou均匀度指数(J),并进行等级聚类(CLUSTER)、非度量多维标度排序(non-metric multi-dimensional scaling,MDS)及丰度/生物量曲线 ...
周政权 +4 more
core +1 more source
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