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Copulatory pattern and behavior in a semi-captive population of Eld＇s deer

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Current Zoology 2011年第3期57卷 284-292页

作者： Zhigao zeng yan-Ling song Qiong ZHANG Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Male copulatory patterns, female multiple copulation and male post-copulatory guarding were studied in Eld＇s deer Cervus eldi in Datian National Nature Reserve, China. Mating behavior in 18 females and 11 males from a group of 61 semi-captive Eld＇s deer were observed. The majority （55.8%） of copulations occurred between 15：00-19：00 h. The ejaculatory mount was preceded by an average of 5.1 prior mounts. Successful copulation consisted of a single thrust with ejaculation during one intromission, with no lock. This copulatory pattern is classified as pattern No. 15 （no lock, no intravaginal thrusting, single intromission, and multiple ejaculation） and No. 16 （no lock, no intravaginal thrusting, single intromission, and single ejaculation） under Dewsbury＇s scheme （1972） and as No. 16 （no lock, no thrusting, single and brief intromission） under Dixson＇s classification （1998）. Copulation frequency was 1.5 ± 0.9 times for males/females with the same female/male per day. The duration of the final mount, which included ejaculation, was brief （3.4±1.3 s）, and ejaculation usually terminated copulation. Eleven females copulated more than once in this study： three of them copulated with several males （multi-male copulations） and the remainder copulated with a single male （repeated copulations）. Our results indicate that some female Eld＇s deer may seek multiple copulations to be a strategy to improve the genetic quality of their offspring or to avoid harassment. Post-copulatory guarding of females by males followed all copulations, with dominant males guarding for significantly longer than subordinate males. Dominant males appear to be more effective at post-copulatory guarding than subordinate males. Subordinate males engaged in a quicker pre-copulatory phase to improve their chances of finishing copulation before being forced to accede to dominant males [Current Zoology 57 （3）： 284-292, 2011].

关键词： Cervus eldi Copulatory pattern Female multiple copulation Post-copulatory guarding Dominant male Subordinate male

Tensile properties and fracture characteristics of spray cast alloy IC6 (Ni-7.8Al-14Mo-0.05B)

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China Foundry 2007年第1期4卷 10-12页

作者： MI Guo-fa WANG Hong-wei TIAN Shi-fan LI Zhou zeng song-yan Henan Polytechnic Institute Jiaozuo 454000 China Harbin Institute of Technology Harbin 150001 China Institute of Aeronautical Materials Beijing 100095 China

Tensile testing results of spray cast Ni3Al-based superalloy indicated that the yield strength and tensile strength increase with the increasing of temperature and reached maximum at around 760℃, then decrease with the increasing of temperature. After high temperature isostatic pressing (HIP), yield strength decreased and ductility and tensile strength increased. Stereographic projection showed that no matter at room temperature, medium temperature or high temperature, cracks extend along (111).

关键词： spray casting Ni3Al-based superalloy tensile properties fracture characteristics

On grain refinement and titanium segregation in Al-Si alloy

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China Foundry 2007年第4期4卷 273-275页

作者： MI Guo-fa WANG Kuang-fei WEN Tao ZHANG Ming WANG Hong-wei zeng song-yan School of Materials Science and Engineering Henan Polytechnic University Jiaozuo 454000 China School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The influence of holding time and distance from sample bottom on segregation and grain refinement of Ti was studied. Results show that Al-STi-IB has an obvious effect on refinement in AI-Si alloy after 4 h holding time. The segregation of Ti shows different morphology at different positions of casting. More segregation is at the bottom of castings because of localized congregation of Ti. The research shows that the difference in Ti concentration is as high as 25.6% between the top and bottom of castings.

关键词： aluminum-silicon alloy Ti segregation grain refinement

钛合金中TiC在高温处理过程中形态变化机制

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材料科学与工艺 2007年第4期15卷 548-552页

作者：金云学曾松岩江苏科技大学先进焊接技术省级重点实验室哈尔滨工业大学材料科学与工程学院黑龙江哈尔滨150001

钛合金中的TiC颗粒形态复杂,尺寸大,不利于合金性能的提高.适当的高温处理工艺可改变TiC/Ti合金中TiC形态和尺寸,本文对不同成分合金在不同高温处理条件下的形态变化规律的详细研究结果表明,当高温处理温度及碳元素在基体中的固溶度不同... 详细信息

钛合金中的TiC颗粒形态复杂,尺寸大,不利于合金性能的提高.适当的高温处理工艺可改变TiC/Ti合金中TiC形态和尺寸,本文对不同成分合金在不同高温处理条件下的形态变化规律的详细研究结果表明,当高温处理温度及碳元素在基体中的固溶度不同时,TiC形态变化机制也不相同,因此总结分析的基础上提出两种TiC形态变化机制,即溶解-析出机制和溶解-固溶-脱溶机制,并理论上详细研究和分析了各种机制下,TiC形态、尺寸变化的原因及机理.

关键词：钛合金复合材料 TiC 热处理形态

Glucocorticoid receptor signaling in the brain and its involvement in cognitive function

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Neural Regeneration Research 2025年第9期20卷 2520-2537页

作者： Chonglin Su Taiqi Huang Meiyu Zhang yanyu Zhang yan zeng Xingxing Chen Brain Science and Advanced Technology Institute Hubei Province Key Laboratory of Occupational Hazard Identification and ControlSchool of MedicineWuhan University of Science and TechnologyWuhanHubei ProvinceChina

The hypothalamic-pituitary-adrenal axis regulates the secretion of glucoco rticoids in response to environmental *** the brain,a nuclear receptor transcription fa ctor,the glucocorticoid recepto r,is an important component of the hypothalamicpituitary-a d renal axis's negative feedback loop and plays a key role in regulating cognitive equilibrium and *** glucoco rticoid receptor influences cognitive processes,including glutamate neurotransmission,calcium signaling,and the activation of brain-derived neurotrophic factor-mediated pathways,through a combination of genomic and non-genomic *** interactions within the central nervous system can alter the expression and activity of the glucocorticoid receptor,there by affecting the hypothalamic-pituitary-a d renal axis and stress-related cognitive *** appropriate level of glucocorticoid receptor expression can improve cognitive function,while excessive glucocorticoid receptors or long-term exposure to glucoco rticoids may lead to cognitive *** with cognitive impairment-associated diseases,such as Alzheimer's disease,aging,depression,Parkinson's disease,Huntington's disease,stroke,and addiction,often present with dysregulation of the hypothalamic-pituitary-adrenal axis and glucocorticoid receptor *** review provides a comprehensive overview of the functions of the glucoco rticoid receptor in the hypothalamic-pituitary-a d renal axis and cognitive *** emphasizes that appropriate glucocorticoid receptor signaling fa cilitates learning and memory,while its dysregulation can lead to cognitive *** provides clues about how glucocorticoid receptor signaling can be targeted to ove rcome cognitive disability-related disorders.

关键词： brain-derived neurotrophic factor calcium signaling glucocorticoid receptor glucocorticoid glutamate transmission hypothalamic-pituitary-adrenal axis long-term potentiation neurocognitive disorders neuroplasticity stress

Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior

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Neural Regeneration Research 2025年第1期20卷 159-173页

作者： Man Han Deyang zeng Wei Tan Xingxing Chen Shuyuan Bai Qiong Wu Yushan Chen Zhen Wei Yufei Mei yan zeng Brain Science and Advanced Technology Institute Wuhan University of Science and TechnologyWuhanHubei ProvinceChina Geriatric Hospital Affiliated to Wuhan University of Science and Technology WuhanHubei ProvinceChina School of Public Health Wuhan University of Science and TechnologyWuhanHubei ProvinceChina

Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral *** studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and *** how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress *** this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of *** focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine *** determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic ***,BDNF might be a biological indicator regulating stress-related processes in various brain regions.

关键词： amygdala chronic mild stress chronic social defeat stress corticolimbic system depression hippocampus medial prefrontal cortex nucleus accumbens social stress models ventral tegmental area

Al/TiC预制合金在锌熔体中溶解过程的试验研究与分析

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铸造 2001年第1期50卷 33-36,51页

作者：王香张二林曾松岩哈尔滨工业大学材料科学与工程学院黑龙江哈尔滨150001

对Al/TiC预制合金在锌熔体中的溶解机理进行了分析。结果表明 :当锌熔体温度低于铝熔点时 ,预制合金的溶解可分为两个阶段 :第一阶段为液态锌向预制合金中浸渗 ,并在预制合金表层内形成Zn Al TiC合金 ;第二阶段为预制合金表层内的Zn Al ... 详细信息

对Al/TiC预制合金在锌熔体中的溶解机理进行了分析。结果表明 :当锌熔体温度低于铝熔点时 ,预制合金的溶解可分为两个阶段 :第一阶段为液态锌向预制合金中浸渗 ,并在预制合金表层内形成Zn Al TiC合金 ;第二阶段为预制合金表层内的Zn Al TiC合金开始溶解并进入锌熔体。利用自制的试验装置测试了Al/TiC预制合金在锌熔体中的溶解量。测定了 430～ 6 5 0℃范围内不同TiC含量的预制合金在锌熔体中的扩散系数 (D)。结果表明 :扩散系数的对数(logD)与温度的倒数 (1/T)近似为线性关系———logD =A0 ·T-1。

关键词： AL/TIC预制合金锌合金溶解机理扩散系数锌熔体复合材料

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热处理工艺对A357合金性能的影响

铸造 2005年第10期54卷 978-980页

作者：朱兆军王宏伟曾松岩哈尔滨工程大学机电工程学院黑龙江哈尔滨150001 哈尔滨工业大学材料科学与工程学院黑龙江哈尔滨150001

研究了热处理工艺参数对A357合金力学性能的影响,并对合金的强化机理进行了分析。研究结果表明A357合金最优化的热处理工艺为:固溶温度(548±3)℃,时间12h;淬火水温度40℃;时效处理温度160℃,时间6h。优化热处理工艺得到合金的性能:抗... 详细信息

研究了热处理工艺参数对A357合金力学性能的影响,并对合金的强化机理进行了分析。研究结果表明A357合金最优化的热处理工艺为:固溶温度(548±3)℃,时间12h;淬火水温度40℃;时效处理温度160℃,时间6h。优化热处理工艺得到合金的性能:抗拉强度为383MPa,伸长率为9.2%。

关键词：热处理工艺 A357合金力学性能

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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Journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei Xue Tong Shi Chenhui Han Heng Zhang Fenrong Liu Haorun Li yan Wang Xiaojun Gu Shanghong zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Nanorods