Results 11 to 20 of about 1,091,898 (247)
Measurement of the A-Value of the Intersystem Transition in Al II at 2670 Å: Å Progress Report [PDF]
International Astronomical Union Colloquium, 1984 Ratios of intensities of spectral lines produced in the radiative decay of collisionally-excited levels of atomic ions are versatile indicators of electron density in astrophysical plasmas when one of the lines involves a metastable level (see the review by Feldman 1981 and references therein). Radiative transition probabilities (A-values) and electron
B. Carol Johnson, H.S. Kwong
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亚洲临床医学杂志, 2021 膝关节是人体最大且结构较为复杂的承重关节，胫骨平台作为其重要的解剖结构，此处的骨折易伴有周围软组织、血管神经的损伤。目前，已经产生了多种分型体系来描述骨折的形态结构，但是没有一种分型能精确涵盖所有类型的骨折。术前选择合理的分型体系对骨折严重程度进行评估，能有效指导治疗及降低术后发生相关并发症的风险。论文针对胫骨平台骨折的分型进展进行综述。
乾坤 王, 鹏 贾
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Optical spectrum of the post-AGB Star HD56126 in the wavelength interval 4010-8790 Å Å [PDF]
Astrophysical Bulletin, 2007 The optical spectrum of the post-AGB star HD56126 identified with the infrared source IRAS07134+1005 is studied in detail using high spectral resolution observations (R = 25000 and 60000) performed with the echelle spectrographs of the 6-m telescope. A total of about one and a half thousand absorptions of neutral atoms and ions, absorption bands of C2,
V. G. Klochkova +3 more
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Zhejiang Daxue xuebao. Lixue ban, 2007 在“分形城市”概念基础上，结合分形理论与住区规划设计的一般内涵，提出了“分形住区”设计思想.“分形住区”设计思想包括分形结构、分形元素和分形组织3个层面内容，每个层面均包涵分形与分维这两个必不可少而又不可分割的基本概念.进而，解释了分形与分维在各个层面上的涵义，完整地论述了“分形住区”的设计思想.最后，文章阐述了“分形住区”设计思想的现实意义，并就研究结论进行了必要的讨论.
QILi-bo(齐立博) +2 more
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工程建设, 2020 粗粒土级配是影响抗剪强度的重要因素之一。在分形理论的基础上，为了探究粗粒土级配与抗剪强度间的相关性规律，设计了五组不同级配的试样，并通过粒度分形曲线求得其分形维数。以室内大三轴试验进行研究，获得了内摩擦角和粘聚力随分形维数增大而减小的变化规律。并通过理论推导获取分形维数与不均匀系数Cu及曲率系数Cc的定量关系式，当分形维数位于(1.89,2.63]这个区间时，可认为级配是良好的。
鑫 黄
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Zhejiang Daxue xuebao. Lixue ban, 2015 利用扫描电镜技术对金银花尺蠖（Heterolocha jinyinhuaphaga Chu）雌雄蛾触角感受器的种类、形态及分布进行了观察.结果发现，金银花尺蠖雌雄蛾触角上共分布9种感受器，分别为毛形感器、刺形感器、鳞形感器、腔形感器、腔锥形感器、耳形感器、腔乳头感器、叉形感器、锥形感器，其中，毛形感器数量最多，叉形感器只存在于雄蛾触角上.
XIANGYuyong(向玉勇) +2 more
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Shuitu Baochi Xuebao, 2004 分形理论和方法为地貌学的非线性研究开辟了新的思路。本文基于分形基本理论和GIS技术,对地处黄土高原丘陵沟壑区第一副区的岔巴沟流域地貌形态分形特征进行了量化研究,提出了流域地貌形态特征分形信息维数的计算模型和方法,并依此获得了岔巴沟流域及各支流域的地貌形态特征分形信息维数。研究表明,岔巴沟流域及各支流域的地貌形态特征分形信息维数均小于1,且与流域面积保持很强的正相关;分形信息维数揭示了流域地貌形态复杂本质的量化特征,为黄土高原小流域侵蚀产沙预报模型中宏观地貌形态因子的量化提供了新的思路和方法。
崔灵周 李占斌 肖学年
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Shuitu Baochi Xuebao, 2022 为探究坡形对浅沟发育的影响，以陕西省靖边县狼儿子沟无人机航摄影像为基础数据，通过目视解译得到浅沟（指瓦背状地形底部）225条，统计了浅沟条数、浅沟长度、沟头到分水岭的距离及浅沟密度等指标。利用浅沟地形分水线上的高程点进行插值得到原始坡面数字高程模型（digital elevation model，DEM），以此DEM提取地形曲率以表征坡形，进而分析坡形与浅沟指标的关系。结果表明：（1）以浅沟地形分水线上的高程点插值后的DEM对浅沟进行了综合，能较好地表达浅沟发育之前原始坡面的地形特征。（2 ...
王海于 +4 more
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Intangible drivers of tolerance shape human–elephant coexistence in Southwest China
People and Nature, EarlyView.Abstract Southwest China is home to a small but rapidly expanding population of Asian elephants (Elephas maximus), whose growth has intensified conflicts with people living in shared landscapes. These conflicts result in substantial economic losses and occasional human casualties. This coexistence paradox—where conservation success leads to significant
Xiaoyu Yu +4 more
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PLANTS, PEOPLE, PLANET, EarlyView.Major staple crops are often introduced and cultivated in monocultures. Yams are staple crops native to the majority of low‐ and middle‐income countries and can provide an alternative to introduced staple crops. We showed that lesser yams cultivated together with teak trees (planted at the border of the farm) are more profitable than lesser yam ...
Budiadi +5 more
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