Results 11 to 20 of about 10,145 (164)
, 2017 ： The pattern of residential land recylcling in China's rural areas has changed into a simple cycle model ， resulting in second abandonment after land consolidation and environmental pollution in some areas.
徐枫 +5 more
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Yb~+注入Si(100)所引起的晶格损伤和快速热退火后Yb的再分布及光激活规律研究 [PDF]
, 1994 稀土元素不完全充满的4f电子壳层被它外部的5p和6s电子壳层有效地屏蔽.这一独特的电子结构使得稀土掺杂半导体材料中4f电子-声子耦合被减弱,因而稀土的发光具有锐利,热稳定性好等优点.近几年国际上已有很多关于用离子注入技术实现稀土掺杂的报道.离子注入具有掺杂浓度高,掺杂分布易于控制,可重复性好和操作简便等优点 ...
岱青 李
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全球能源互联网, 2020 在中国电力消纳保障机制和新配额制的实施背景下，为了使省内消纳责任主体完成消纳考核，如何利用市场机制激励可再生能源跨省跨区消纳是关键问题之一。为此，借助于省间-省内两级市场，引入了省间可再生能源交易商代理省内消纳责任主体参与省间可再生能源市场交易。在两级市场框架下，以市场运行成本最小化为目标，建立了一种非线性的双层优化消纳模型。上、下层的出清结果作为对方层级的计算参数，利用KKT（Karush-Kuhn-Tucker）条件和拉格朗日对偶理论，将上述双层非线性问题转化为单层线性问题求解。最后 ...
陈先龙 +5 more
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野生动物学报, 2023 为有针对性地制定朱鹮（Nipponia nippon）保护计划，促进朱鹮再引入，壮大野外种群规模，2014—2019年7—11月，对河南董寨再引入朱鹮的35个巢址及其周边 3 m×3 m样方的22个生境特征进行观察、测量和记录。结果表明：大多数巢筑于针阔混交林（n=23）和针叶林（n=10）。在野化放飞初期，朱鹮对营巢树种选择相对多样，但后期对大别山低山区马尾松（Pinus massoniana）显现明显的偏好（n=27，占81.8%）。筑巢树的平均胸径（35.53±9.82）cm，平均高度 ...
朱家贵 +6 more
doaj
Developmental Medicine &Child Neurology, Volume 61, Issue 3, Page E1-E35, March 2019., 2019 目的 本国际临床指南由欧洲残疾儿童学会（the European Academy of Childhood Disability，EACD）牵头制定，旨在解决发育性协调障碍（developmental coordination disorder，DCD）的定义、诊断、评估、干预以及与社会心理方面的临床应用关键问题。 方法 本指南针对五个领域的关键问题，通过文献综述和专家团队的正式讨论达成共识。为保证指南的循证基础，以“机制”、“评估”和“干预”为检索词, 对2012年更新以来提出的最新建议以及新增的“社会心理问题”和“青少年/成人”为检索词进行检索。根据牛津大学循证医学中心证据等级 (证据水平 [level of evidence, LOE]1–4) 将结果进行分类，最终转化为指南建议。并由国际 ...
Jing Hua +6 more
wiley +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2007 尝试在深度方向引入PML（完美的匹配层）选取适当的非线性局部坐标正交变换及方程变换，将Helmholtz方程uxx+uzx+k2(x，z)u = 0变换为，然后再选取非对称Rayleigh商迭代算法来求解Helmholtz方程的特征问题，即求解的特征值和特征函数.数值模拟表明，此方法是可行的，并可以大大改善数值求解的效率.
WANGDan-xi(王丹溪) +1 more
doaj +1 more source
Orphan crops of archaeology‐based crop history research
PLANTS, PEOPLE, PLANET, Volume 7, Issue 3, Page 562-589, May 2025.Agrobiodiversity is central to sustainable farming worldwide. Cultivation, conservation and reintroduction of diverse plant species, including ‘forgotten’ and ‘underutilized’ crops, contribute to global agrobiodiversity, living ecosystems and sustainable food production.
Daniel Fuks +23 more
wiley +1 more source
Postnatal outcome following fetal aortic valvuloplasty for critical aortic stenosis
Ultrasound in Obstetrics &Gynecology, Volume 64, Issue 3, Page 339-347, September 2024.ABSTRACT Objective To report our experience of fetal aortic valvuloplasty (FAV) for critical aortic stenosis (AS), with a focus on the postnatal evolution of the patients. Methods This was a retrospective study including all fetuses with critical AS which underwent FAV in a single center between January 2011 and June 2022.
R. Corroenne +14 more
wiley +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2002 鉴于金华仙源湖水利旅游区区内自然山水旅游资源的局限,在开发中我们转而以更广大的区域为背景,寻找山水自然风光与深邃文化意蕴密切结合的途径,大胆引入新的文化因素,确立了以中国古典文学样式的代表之一"词文化"为主线的高品位文化主题;再围绕这一主题进行景观设计,赋自然山水以词情画意,取得了较好效果.
FANJin-zhao(范今朝) +1 more
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Methods in Ecology and Evolution, Volume 15, Issue 8, Page 1408-1421, August 2024.Abstract Environmental DNA (eDNA) monitoring of species distribution has become a critical tool in ecology, conservation biology and fisheries for identifying the presence and distribution of diverse organisms, including important, threatened and invasive species.
Jiwei Yang +4 more
wiley +1 more source