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Functional Ecology, Volume 40, Issue 7, Page 2068-2082, July 2026.Read the free Plain Language Summary for this article on the Journal blog. Abstract Grasslands worldwide are experiencing severe degradation due to overgrazing, climate change and anthropogenic disturbances, resulting in substantial declines in biodiversity and ecosystem functioning.
Xiaoqi Wang +5 more
wiley +1 more source
, 2016 受限液丝断裂是很多自然界或工业过程中的基础现象,例如多孔介质中微孔内的液丝断裂、微通道中液滴或气泡的生成等。一般认为低流量情况下的液丝断裂动力学由界面张力主导,但对于界面毛细失稳的起源的认识仍然不清楚,甚至有相互矛盾的观点。我们通过直接数值模拟和高速摄影得到了微流控装置中毛细失稳的临界条件,并确定了两种毛细失稳机制。一种是几何限制引起的表面毛细压力梯度,促使液丝失稳;另一种是由于局部毛细压力液丝内部压力的竞争,当局部毛细压力大于液丝内部压力时液丝失稳 ...
薛春东, 陈晓东, 胡国庆
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Jianzhu Gangjiegou Jinzhan为研究T形钢管混凝土柱-H形钢梁侧接板式节点的受力机理，对该节点进行了有限元模拟和理论分析研究。首先建立Abaqus有限元数值模型，通过试验结果验证了数值模型的合理性；根据节点构造特点，推导了该节点的受弯承载力和受剪承载力计算公式，并采用数值模型算例进行验证；基于计算公式分析不同变量对节点受弯承载力和受剪承载力的影响。研究结果表明：给出的有限元模型能够有效模拟侧接板式节点的工作状态和极限承载力；侧接板式节点的受弯破坏有4种破坏形态，通过合理构造可以确保首先出现钢梁翼缘受拉屈服破坏，实现节点的延性破坏 ...
程卫红, 储德文, 时继瑞
doaj +2 more sources
Dianci bileiqi, 1998 从非欧姆导电机理、老化机理的深化和完善、功能微观结构作用和控制、粉料预处理和制造技术等方面对zno压敏电阻片的基础理论研究进行了概括；并指出，从技术发展动态看，主要是降低残压比、提高单位体积的能量耐受能力、提高压敏电位梯度、提高长期老化性能。
1.西安交通大学电气绝缘研究所!西安 +1 more
doaj
Functional Ecology, Volume 40, Issue 7, Page 2332-2344, July 2026.Read the free Plain Language Summary for this article on the Journal blog. Abstract The stoichiometric ratios of carbon (C), nitrogen (N) and phosphorus (P) serve as important indicators for assessing nutrient balance in forest ecosystems, but their relationships with photosynthetic dynamics require deeper characterization.
Minghao Chen +9 more
wiley +1 more source
Shiyou jixie, 2015 油管悬挂器是水下采油树的核心部件，其锁紧机构对油管悬挂器至关重要。阐述了油管悬挂器锁紧机构的组成、锁紧及解锁原理，确定了锁紧方案和解锁方案。对锁紧块在锁紧和解锁工况下的受力进行分析，得出2种工况下的推动环倾角均为45°。分析了单齿锁紧块和多齿锁紧块的受力情况和力传递途径，推导出单齿锁紧块和多齿锁紧块在X方向和Y方向的受力方程。建立了单齿轮廓和双齿轮廓的有限元模型，研究不同锁紧齿数对载荷传递路径的影响及不同路径应力分布。研究结果表明，2齿形的锁紧块结构更适合油管悬挂器的锁紧机构。
梅静 +4 more
doaj
Functional Ecology, Volume 40, Issue 7, Page 2128-2142, July 2026.Read the free Plain Language Summary for this article on the Journal blog. Abstract Soil organic nitrogen (SON) transformation is critical for global nutrient cycling and ecosystem productivity, yet how its responsiveness to climate change differs across diverse land use types remains poorly resolved.
Xinyi Yang +10 more
wiley +1 more source
Dehydrogenation Thermodynamic and Kinetic Challenges of Mg‐Ni‐Based Alloy Hydrides
Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT Solid‐state hydrogen storage stands as a pivotal, safe, and efficient solution for the future hydrogen economy. Among diverse hydrogen storage systems, Mg‐Ni‐based alloy hydrides are recognized as cornerstone materials. However, their practical application is hindered by two core challenges: the high thermodynamic stability of the hydride ...
Jinglan He +6 more
wiley +1 more source
, 1984 从原则上讲,微处理机的中央处理单元 CPU 可以完成各种运算。然而实际上,除了简单的加减法和逻辑操作之外,一般运算都需要很长的过程。近来,随着微处理机的发展和完善,出现了专用的运算处理单元 APU。它是一个复杂的、完善的、高性能和高速度的独立单元。它是为提高微处理机运算能力而设计的。它不但能进行定点的而且还能进行浮点的运算。它不仅能完成四则运算,而且还能完成全套的超越函数运算。另外,它还具有控制和变换功能。CPU把数据与运算指令送给 APU 之后,便可中断,并等待 APU 运算的完成。这种程序极易编写 ...
原苏华, 周德广, 郭爱力
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