Results 31 to 40 of about 25,822 (190)
Biodiversity‐driven spatial conservation planning to delineate temporally stable regions
Conservation Biology, EarlyView.Abstract The accelerating loss of biodiversity underscores the critical need for effective conservation strategies, particularly in the face of climate change and anthropogenic pressures. We devised a conservation planning framework that adopts a temporal stacking approach to species distribution models and landscape connectivity analyses. These models
Mattia Iannella +5 more
wiley +1 more source
Preparation and Characterization of BN Coating on SiC Fibers by Carbothermal Reduction [PDF]
, 2016 本论文以硼酸三甲酯（trimethylborate—TMB）蒸气为硼源、NH3气为氮源，采用碳热还原氮化法在SiC纤维表面制备BN涂层。首先，SiC纤维与Cl2气反应表面生成碳化物衍生碳（carbide-derivedcarbon—CDC）层，然后，CDC层与TMB蒸气及NH3气在1300C发生碳热还原氮化反应，生成BN涂层。采用FT-IR、XPS、XRD、AES、SEM、TEM、电阻率测试、单丝拉伸试验等系统地研究了所得BN涂层的组成、结构和性能。研究发现 ...
袁梦娇
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
Efficient Simulation Methods for Reinforced Concrete Columns with Encased Steel in High-rise Building Structures [PDF]
, 2016 型钢混凝土柱在建筑结构中往往是主要的承重构件之一，使用合适的数值模型分析其力学性能对高层结构抗震分析有重要的意义。本文综述了目前文献中已有的低含钢率恢复力模型相关研究，分析了其理论、计算流程和算法，并在通用有限元软件OpenSees中编程实现。本文详细推导了模型中基本参数的确定方法，并用于模拟实际高层建筑结构中的型钢混凝土柱。首先，本文用恢复力模型模拟了单根型钢混凝土柱的试验，通过对比验证了模型的精度，研究了其计算效率。其次，本文将恢复力模型用于理想32层高层结构中的单排型钢混凝土构件静、动力分析中 ...
曾志弘
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
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
To cultivate students’ creative thinking and self-study ability by class discussion
Huli yanjiu, 2005 [目的]通过课堂讨论培养学生的自学创新思维能力。[方法]在护理本科专业《护理学基础》课程中开展课堂讨论教学,采用以学生为主体进行选题、讨论及效果评价等方法。[结果]通过课堂讨论,93 .6%的学生提高了检索、查阅能力,93 .6%的学生提高了自学能力,87.4%的学生提高了探究性思维的能力,92 .1%学生提高了分析归纳总结能力,84.2 %的学生提高了发现问题和解决问题的能力。[结论]课堂讨论教学方法能引导学生学会自学,激发学习兴趣,并促进其创新思维能力的培养。
姜今玉, 杨顺子
doaj
In-situ Raman Observations of PLZT Ferroelectric Ceramics under Stress Fields [PDF]
, 2015 在外场作用下铁电陶瓷材料的畴变会造成材料微结构的变形，最终会引发材料的性能退化、材料失效。因此了解铁电材料的破坏机理，研究外场作用下铁电材料的畴变规律，对提高铁电材料的使用价值具有指导性的意义。为探讨力场作用下铁电陶瓷的畴变规律，本论文开展了外力场作用下铁电陶瓷拉曼光谱变化的原位观测研究。论文工作包括：利用固相反应法合成了组成为Pb0.9La0.1(Zr0.52Ti0.48)0.975O3且晶粒尺寸（约5m）适于原位拉曼光谱观测的铁电多晶陶瓷；对合成出的PLZT铁电陶瓷进行化学组分 ...
梁丽苹
core
Assessing differences among elasmobranch nurseries to aid conservation based on a genomics framework
Conservation Biology, EarlyView.Abstract Elasmobranch nurseries often differ in environmental conditions, demographics, and use patterns. These differences affect the distribution of genetic variation among nurseries. However, conservation and management strategies often fail to account for such differences because they are difficult to characterize.
Dominic G. Swift +8 more
wiley +1 more source
Jianzhu Gangjiegou Jinzhan, 2017 经历不均匀热过程影响的对接焊接接头,呈现不均匀力学性能。在对对接焊接接头疲劳等分析过程中,应考虑不均匀力学性能。根据对接焊接接头分区和力学性能分布,提出了3种对接焊接接头不均匀力学性能分布模式:二区模式、五区模式和连续化模式。采用有限元方法分析材料力学性能不均匀模式对对接焊接结构性能分析的影响。采用3种模式结合已有试验数据,建立了不同精细化程度的有限元模型并进行有限元分析。研究结果表明:分布模式对结果会产生很大的影响,模式越精细,屈服荷载、极限荷载和屈服位移、极限位移就越小 ...
甘结良, 彭洋, 董军
doaj