Results 81 to 90 of about 173,503 (241)
Zhongguo shiyan zhenduanxue, 2009 目的探讨驻疆边防官兵功能性胃肠疾病（functional gastrointestinal disorders,FGIDs）的发病情况及其相关影响因素。方法按照FGIDs罗马Ⅲ分类及诊断标准,对驻疆边防官兵进行问卷调查。按国际统一评判方法（SA forRomeⅢ-DQ）对各种功能性胃肠疾病进行诊断。结果①抽样调查官兵1062人,FGIDs总发病人数333例,总发病率为31.34%。其中肠易激综合征（irritable bowel syndrome,IBS）发病率最高,为21.06%,其次为功能性烧心9 ...
尚军, 杨云生
doaj
A Microstructure and Mechanical Property Study of Maraging Steel PH13-8Mo in Nuclear Applications [PDF]
, 2015 马氏体时效强化不锈钢具有杰出的机械性能，且在高温服役环境中表现稳定，因而在航空和传统能源领域广受青睐。此外，材料的热膨胀系数均匀，良好的抗腐蚀性能以及时效前优良的加工特性也引起了核能业界的关注。由于时效后的材料内部能够析出大量细小弥散的NiAl金属间化合物，形成吸收辐照损伤空位的势阱，为材料的耐辐照性能创造了客观条件，马氏体时效强化不锈钢也成为了重要的新一代反应堆备选结构材料。 本论文从研究马氏体时效强化不锈钢PH13-8Mo的长周期高温性能变化出发，在450、500和600 ...
黄子敬
core
Drivers of bat researchers’ intent to adopt field hygiene practices
Conservation Biology, EarlyView.Abstract Infectious disease is a growing threat to wildlife, with zoonotic transmission most likely at the human–wildlife interface. One underappreciated activity at this interface is fieldwork with wild animals, but associated risks can be mitigated through field hygiene (FH) practices, such as using personal protective equipment and other appropriate
Joanna L. Coleman +6 more
wiley +1 more source
Dianci bileiqi, 2022 由于复合绝缘子出现鸟啄、异常发热、酥朽断裂等运行问题，研究人员尝试采用新型脂环族环氧树脂材料代替常用的硅橡胶。为了评估脂环族环氧树脂的综合性能，通过脂环族环氧树脂和硅橡胶的憎水性、憎水迁移性、耐漏电起痕、介电常数、介电损耗、平均断裂能量等试验数据对比研究了二者的运行性能。研究结果表明相比于硅橡胶材料，脂环族环氧树脂材料同样具有优良的憎水性、憎水迁移性和介电性能，且脂环族环氧树脂的耐漏电起痕性能和缺陷扩展性能优于硅橡胶。
曾向君 +5 more
doaj
Studies on Conversion of Methanol to Aromatics over Modified Zeolite and Composite Zeolite Catalysts [PDF]
, 2016 随着石油资源的不断消耗和对芳烃（特别是苯、甲苯及二甲苯，即BTX）需求量的日益增加，经甲醇制芳烃（MTA）的过程引起了广泛关注。目前MTA反应主要存在芳烃收率不高及催化剂易积碳失活等问题，本论文以高选择性制备BTX为目标，以改性H-ZSM-5及合成复合型分子筛为策略，详细研究了分子筛的酸性及孔道结构对MTA反应产物选择性及稳定性的影响。 论文首先考察了不同分子筛上甲醇芳构化反应性能，发现H-ZSM-5具有最高的BTX收率。通过对比不同硅铝比H-ZSM-5的反应性能，发现低硅铝比有利于BTX的生成 ...
沈鑫权
core
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
フラクタル符号化特徴量を用いた類似画像検索およびオブジェクト検出手法の検討 [PDF]
, 2019 Fractal image coding is a block-based scheme that exploits the self-similarity hiding with an image. Fractal codes are quantitative measurements of the self-similarity of the image, and collage error distribution of block characterizes the degree of self-
鶴見, 智
core
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
Jianzhu Gangjiegou Jinzhan, 2012 防屈曲开缝钢板墙是一种新型的抗侧力构件,除具有一般钢板墙的特点外,还具有塑性性能好、滞回特性稳定以及可以独立地变化墙板承载力和刚度等优点。目前,有学者针对该结构体系提出基于性能设计的能力设计法和能力准则法,采用上述理论以及日本被动减震结构的设计方法（性能需求法）,对1榀6层3跨的防屈曲开缝钢板墙结构算例进行了分析,比较研究了3种方法对结构性能的影响。计算结果表明:对于能力设计法,适当提高墙板的设计屈服位移,可以有效地增大结构的延性;能力准则法需要多次试算,结构性能指标不易控制 ...
孙飞飞, 张葳, 李立树
doaj
Conservation Biology, EarlyView.Abstract Bycatch in fisheries is one of the most serious threats to pelagic seabirds, causing major population declines. Mitigation measures can reduce bycatch substantially, but many fisheries fail to apply best practices, and seabird mortality remains high.
V. Warwick‐Evans +2 more
wiley +1 more source