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恶劣综采工况条件下的采煤机摇臂散热设计研究

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煤矿机械 2025年第1期46卷 35-37页

作者：马兰上海创力集团股份有限公司上海201706

简述了在采煤机设计过程中对恶劣综采工况中工作倾角较大、煤岩硬度较硬、截割功率大且结构紧凑限制条件下的摇臂热功率的计算,分析了该工况中摇臂简化为复杂齿轮箱思路下的热功率计算、散热途径和热平衡点,提出了摇臂内部结构改进及增... 详细信息

简述了在采煤机设计过程中对恶劣综采工况中工作倾角较大、煤岩硬度较硬、截割功率大且结构紧凑限制条件下的摇臂热功率的计算,分析了该工况中摇臂简化为复杂齿轮箱思路下的热功率计算、散热途径和热平衡点,提出了摇臂内部结构改进及增加外置冷却装置的散热设计方案,并验证了满载试验条件下摇臂截割热平衡温度不超过90℃的方案可行性。

关键词：大功率大倾角采煤机摇臂紧凑结构热功率热平衡

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不同类型学业压力对不同年级高中生执行功能子成分的影响

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心理学报 2025年第1期57卷 18-35页

作者：马超汪彦云付军军赵鑫甘肃省行为与心理健康重点实验室西北师范大学心理学院兰州730070

选取985名高一~高三年级的学生,采用相关分析和结构方程模型等方法考察了学业压力4个子维度在不同年级高中生各执行功能成分中的作用。结果发现,随着高中生年级的升高,父母压力和教师压力对各执行功能成分的负向预测作用逐渐增强,社交... 详细信息

选取985名高一~高三年级的学生,采用相关分析和结构方程模型等方法考察了学业压力4个子维度在不同年级高中生各执行功能成分中的作用。结果发现,随着高中生年级的升高,父母压力和教师压力对各执行功能成分的负向预测作用逐渐增强,社交压力对各执行功能成分的负向预测作用逐渐减弱。相比之下,自我压力对高中生的干扰抑制、反应抑制和注意转换能力均显示出了正向预测作用,并随年级的升高而增强。这表明,不同类型学业压力对各执行功能成分的预测作用存在差异,并将随高中生年级的升高而发生变化。本研究所产生的结论对于教育工作者有效制定高中生学业压力应对策略具有重要的启示意义。

关键词：执行功能学业压力高中生结构方程模型

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Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros-mañé Laia Just-Borràs marta Balanyà-Segura Aleksandra Polishchuk Laura Nadal marta Tomàs Carolina Silvera-Simón manel M.Santafé maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

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新生儿败血症的规范管理与挑战

中华儿科杂志 2025年第1期63卷 2-5页

作者：马晓路杜立中浙江大学医学院附属儿童医院新生儿监护中心杭州

新生儿败血症是导致新生儿死亡和严重并发症的重要原因, 早期诊断并及时治疗是改善预后的关键。应在风险预测、临床评估的基础上, 结合实验室检查结果进行新生儿败血症诊断, 避免过度抗生素治疗。规范化管理和质量改进项目有助于减少医...

新生儿败血症是导致新生儿死亡和严重并发症的重要原因, 早期诊断并及时治疗是改善预后的关键。应在风险预测、临床评估的基础上, 结合实验室检查结果进行新生儿败血症诊断, 避免过度抗生素治疗。规范化管理和质量改进项目有助于减少医院内获得性感染的发生。

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基于分子束外延技术可控制备Bi原子团簇的研究

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原子与分子物理学报 2025年第2期42卷 79-84页

作者：马玉麟郭祥丁召贵州大学大数据与信息工程学院贵阳550025 贵州省微纳电子与软件技术重点实验室贵阳550025 半导体功率器件可靠性教育部工程研究中心贵阳550025

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇... 详细信息

本研究基于分子束外延(MBE)技术在Si(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇的密度,当温度升高100℃,密度从1.05×10^(11)cm^(-2)降低至2.5×10^(7)cm^(-2),实现对团簇密度4个数量级的可控调节,并且发现Bi原子团簇密度对生长温度的依赖性符合经典成核理论.其次,分别在10 s、15 s、20 s的沉积时长下,制备了密度相同、尺寸各异的Bi原子团簇.实验结果表明,可以通过改变沉积时长来精细控制Bi原子团簇的尺寸:当沉积时长增加10 s,高度和直径分别从8.5 nm和65 nm增大到13.7 nm和100 nm,实现对团簇尺寸在10 nm高度、80 nm直径范围的可控调节,并且发现Bi原子团簇尺寸对沉积时长的依赖性符合晶体生长动力学.与分子束外延制备传统的Ⅲ族(Al,Ga,In)原子团簇做对比,这些结果可以为制备Ⅴ族原子团簇提供实验参考和指导,从而促进纳米级含Bi材料的制备.

关键词：分子束外延 Bi原子团簇生长温度沉积时长经典成核理论晶体生长动力学

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基于分子束外延技术可控制备Ga原子团簇的研究

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原子与分子物理学报 2025年第3期42卷 77-84页

本研究基于分子束外延(Molecular Beam Epitaxy,MBE)技术在Si(100)衬底表面成功制备金属Ga原子团簇.通过控制变量法,研究其尺寸形貌与工艺参数之间的关系.第一组对照实验分别在940℃、970℃、1000℃的Ga源温度下制备Ga原子团簇.实验结... 详细信息

本研究基于分子束外延(Molecular Beam Epitaxy,MBE)技术在Si(100)衬底表面成功制备金属Ga原子团簇.通过控制变量法,研究其尺寸形貌与工艺参数之间的关系.第一组对照实验分别在940℃、970℃、1000℃的Ga源温度下制备Ga原子团簇.实验结果表明,Ga源温度的升高导致Ga的蒸发量增加,进而沉积在Si衬底表面的Ga原子增多,Ga原子自组装成团簇,最终表现为Ga原子团簇的高度升高.第二组对照实验分别在3 s、6 s、10 s、40 s、50 s、60 s的沉积时长下制备Ga原子团簇.实验结果表明,沉积时长增加导致团簇的高度逐渐增加,主要由新吸附原子和竞争效应驱动.第三组对照实验分别在0 s、60 s、300 s的退火时长下制备Ga原子团簇.实验结果表明,退火时长的增加导致团簇的高度下降和团簇内的原子重新排列和分布有关.第四组对照实验分别在420℃、500℃的退火温度下制备Ga原子团簇.实验结果表明,升温至500℃退火会促进Ga原子团簇呈现有序排列,是表面原子的热运动和Ga原子团簇与Si(100)的晶格匹配度的共同作用的结果.

关键词： MBE Ga原子团簇 Ga源温度沉积时长退火时长

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Revealing the crystallization process and realizing uniform 1.8 eV ma-based wide-bandgap mixed-halide perovskites via solution engineering

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Nano Research 2019年第5期12卷 1033-1039页

作者： Yue-Min Xie Chunqing ma Xiuwen Xu Menglin Li Yuhui ma Jing Wang Hrisheekesh Thachoth Chandran Chun-Sing Lee Sai-Wing Tsang Department of materials Science and Engineering City University of Hong KongHong Kong SARChina City University of Hong Kong Shenzhen Research Institute Shenzhen 518057China Center of Super-Diamond and Advanced Films (COSDAF) City University of Hong KongHong Kong SARChina

Wide-bandgap perovskites are recently drawing tremendous attention in the community for high-efficiency all-perovskite tandem solar ***,the formamidinium (FA^+) and methylammonium (ma^+) based wide-bandgap mixed halide perovskites suffered from high density of traps and pin-holes,*** understanding on the crystallization and film formation processes are keys to overcome those challenges but not yet clearly *** this study,an in-situ photoluminescence technique was used to investigate the perovskite crystallization during the thermal annealing *** is found that the crystallization of a mixed halide perovskite with bromide (Br^-) and iodine (I^-) ions following the Ostward ripening crystal ***,it is found that the initial nucleation reaction is quickly completed in the first few seconds,however,leaving the small crystals with inhomogeneous *** different aggregation affinities of such inhomogeneous small crystals provoke the formation of pin-holes during the thermal annealing *** engineering the precursor solution to control the nucleation rate,the chemical composition of the small crystals has become *** pin-hole free high Br-composited wide-bandgap ma0.9Cs0.1Pb(I0.6Br0.4)3 perovskite films with bandgap energy of 1.8 eV have been *** corresponding photovoltaic devices have achieved an encouraging device efficiency of 15.1% with superb photostability.

关键词： in-situ photoluminance wide-bandgap perovskite pin-holes solution engineering

Impact of Bubbles on Mechanical Performances in a Borosilicate Glass

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Journal of Wuhan University of Technology(materials Science) 2025年第1期 25-29页

作者：李成行 LI Dongfeng ma Shilong QIAO Ang 郑庆双 China Helicopter Research and Development Institute State Key Laboratory of Silicate materials for Architectures Wuhan University of Technology

To analyze the impact of bubbles on the mechanical behavior of glasses,by controlling the refining time,we prepared three borosilicate glasses with the same composition and different *** the analysis software integrated within the optical microscope,the diameter and number of the bubbles on the surface of three borosilicate glasses were *** the hardness and crack initiation resistance （CR）,we built the relationship between the porosity and the mechanical performance of these borosilicate glasses.

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FDNet: Fourier transform guided dual-channel underwater image enhancement diffusion network

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Science China Technological Sciences 2025年第1期 62-78页

作者： Zhen ZHU Xiaobo LI Qianwen ma Jingsheng ZHAI Haofeng HU School of marine Science and Technology Tianjin University College of Mechanical Engineering and Automation Fuzhou University

Due to the scattering and absorption of light, underwater imaging yields suboptimal results characterized by low brightness, diminished image contrast, and the loss of details. Current learning-based underwater image enhancement(UIE)methods mainly focus on addressing these issues in the spatial domain, with limited attention to the Fourier frequency *** propose the Fourier transform guided dual-channel underwater image enhancement diffusion network(FDNet), aiming to fully leverage frequency domain information and the characteristics of a diffusion-based generation model. The amplitude-phase dualchannel not only effectively provides feedback on the energy distribution of the image but also incorporates crucial image structure and texture information. Capitalizing on these advantages, we first introduce a Fourier transform-based amplitude-phase dualchannel enhancement front-end network for UIE. This network significantly improves the quality of the network's image input,including brightness and contrast, by incorporating phase congruency edge enhancement and prior-driven amplitude mapping strategies. The preceding network mitigates the overall training challenges caused by poor input image quality. Simultaneously,the application of denoising networks based on lightweight transformers effectively improves the computational time required for each iteration during model training. The results indicate that FDNet outperforms many current learning-based UIE algorithms in restoring images across multiple real underwater image datasets, demonstrating more robust generalization capabilities in degraded underwater scenarios. The competitive performance advantage achieved in enhancing visual quality underscores the effectiveness of our method.

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