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Science China Mathematics 2024年第4期67卷 787-818页

作者： min liang Yaobin Ou School of Mathematics Renmin University of ChinaBeijing 100872China

This paper verifies the low Mach number limit of the non-isentropic compressible magnetohydrodynamic(MHD)equations with or without the magnetic diffusion in a three-dimensional bounded domain when the temperature variation is large but *** uniform estimates of strong solutions are established in a short time interval independent of the Mach number,provided that the slip boundary condition for the velocity and the Neumann boundary condition for the temperature are imposed and the initial data is well-prepared.

关键词： low Mach number limit non-isentropic compressible magnetohydrodynamic equations large temperature variations bounded domains

Ligand-controlled NiH-catalyzed regiodivergent hydroalkylation of 2-alkenylazaarenes

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Science China Chemistry 2024年第6期67卷 1935-1940页

作者： Ya-Ping Shao Zhuo-min Chi Yong-min liang State Key Laboratory of Applied Organic Chemistry School of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000China

A nickel-hydride(Ni H)-catalyzed migratory and nonmigratory hydroalkylation reaction of 2-alkenyl azaarenes with alkyl iodines has been established through strategic modulation of N-or P-donor *** method enables the synthesis of diverseβ-orγ-branched aromatic *** mild regiodivergent protocols exhibit wide substrate scope,excellent functional tolerance,and great reaction yield with remarkable ***,deuterium labeling studies reveal Ni H-catalyzed interrupted chain-walking mode as the mechanism behind remotedβ-selective hydroalkylation reaction—an interesting phenomenon mediated through aromatic imine directing groups.

关键词： NiH regiodivergent hydroalkylation azaarenes interrupted chain-walking

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Revisiting the island of hexadecapoledeformation nuclei in the A≈150 mass region:focusing on the model application to nuclear shapes and masses

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Communications in Theoretical Physics 2024年第2期76卷 74-88页

作者： Xiao-Yang Wei Hua-Lei Wang Zhen-Zhen Zhang min-liang Liu School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Based on the potential-energy-surface calculation,the impact of different deformation degrees of freedom on a single-particle structure and binding energies in nuclei around^(152)Nd,located on one of the hexadecapole-deformation islands,is analyzed in a multi-dimensional deformation *** energy maps,curves and tables are presented to indicate nuclear *** calculated equilibrium deformations and binding energies with different potential parameters are compared with experimental data and other *** is found that the inclusion of the hexadecapole deformations,especially the axial one,can improve the theoretical description of both nuclear shapes and *** addition,our calculated potential-energy curve shows that a critical deformation-point,β_(2)≈0.4,exists—the triaxial(hexadecapole)deformation effect can be neglectable but the hexadecapole(triaxial)one plays an important role before(after)such a critical point.

关键词： hexadecapole deformation binding energy potential-energy-surface calculation nuclear property

Impact of propofol and sevoflurane anesthesia on cognition and emotion in gastric cancer patients undergoing radical resection

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 79-89页

作者： Ao-Han Li Su Bu Ling Wang Ai-min liang Hui-Yu Luo Department of Anesthesiology Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina Department of Cardiothoracic Surgery Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina Department of Rehabilitation Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina Department of Internal Medicine-Cardiovascular Xiangyang No.1 People's HospitalHubei University of MedicineXiangyang 441000Hubei ProvinceChina

BACKGROUND Propofol and sevoflurane are commonly used anesthetic agents for maintenance anesthesia during radical resection of gastric ***,there is a debate concerning their differential effects on cognitive function,anxiety,and depression in patients undergoing this *** To compare the effects of propofol and sevoflurane anesthesia on postoperative cognitive function,anxiety,depression,and organ function in patients undergoing radical resection of gastric *** A total of 80 patients were involved in this *** subjects were divided into two groups:Propofol group and sevoflurane *** evaluation scale for cognitive function was the Loewenstein occupational therapy cognitive assessment(LOTCA),and anxiety and depression were assessed with the aid of the self-rating anxiety scale(SAS)and self-rating depression scale(SDS).Hemodynamic indicators,oxidative stress levels,and pulmonary function were also *** The LOTCA score at 1 d after surgery was significantly lower in the propofol group than in the sevoflurane ***,the SAS and SDS scores of the sevoflurane group were significantly lower than those of the propofol *** sevoflurane group showed greater stability in heart rate as well as the mean arterial pressure compared to the propofol ***,the sevoflurane group displayed better pulmonary function and less lung injury than the propofol *** Both propofol and sevoflurane could be utilized as maintenance anesthesia during radical resection of gastric *** anesthesia has a minimal effect on patients'pulmonary function,consequently enhancing their postoperative *** anesthesia causes less impairment on patients'cognitive function and mitigates negative emotions,leading to an improved postoperative mental ***,the selection of anesthetic agents should be based on the individual patient's specific circumstances.

关键词： Propofol Sevoflurane Radical resection of gastric cancer Anesthetic effect Cognitive function Negative emotion

Exploration and Practice of Big Data Introductory Courses for Big Data Management and Application Majors

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Journal of Contemporary Educational Research 2024年第2期8卷 131-137页

作者： Tinghui Huang Junchao Dong liang min School of Computer Science and Information Security Guilin University of Electronic TechnologyGuilin 541004Guangxi Zhuang Autonomous RegionChina School of Computer Engineering Guilin University of Electronic TechnologyBeihai 536000Guangxi Zhuang Autonomous RegionChina The Youth Innovation Team of Shaanxi Universities Xi’an Jiaotong University City CollegeXi’an 710018Shaanxi ProvinceChina

As an introductory course for the emerging major of big data management and application,“Introduction to Big Data”has not yet formed a curriculum standard and implementation plan that is widely accepted and used by *** this end,we discuss some of our explorations and attempts in the construction and teaching process of big data courses for the major of big data management and application from the perspective of course planning,course implementation,and course *** interviews with students and feedback from questionnaires,students are highly satisfied with some of the teaching measures and programs currently adopted.

关键词： Big data management and application “Introduction to Big Data” Teaching reform Curriculum exploration

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纯电动绿色船舶长航程航次规划与充换电策略

交通运输工程学报 2024年第3期24卷 266-278页

作者：梁民仓王胜正上海海事大学商船学院上海201306 浙江海洋大学船舶与海运学院浙江舟山316022

针对纯电动船舶长航程航次规划和充换电站选址的动态规划问题,提出了一种可行的多变量、多目标优化模型,实现航速和充换电策略的同步优化;建立了能耗最低和航时最短的双目标函数,分析了影响纯电动船舶长航程航次规划的环境和操作因素,... 详细信息

针对纯电动船舶长航程航次规划和充换电站选址的动态规划问题,提出了一种可行的多变量、多目标优化模型,实现航速和充换电策略的同步优化;建立了能耗最低和航时最短的双目标函数,分析了影响纯电动船舶长航程航次规划的环境和操作因素,构建了航速、航时和能耗约束条件;研究了集装箱式电池运营管理模式,建立了能量补给按照实际耗电量计费和更换电池一次性计费2种优化模型;利用非支配排序遗传算法完成了模型求解并进行试验案例验证。研究结果表明:基于案例数据条件,优化前以保证续航到第2个充换电站进行补给的最大平均航速8.5 kn计算,需耗能96637.7 kWh、总航时62.1 h;以实际耗电量计费时,采用优化模型得到的充换电策略均是在第2个充换电站进行补给,以最短航时为优化目标时总航时仅需56.9 h,以最低能耗为优化目标时总能耗仅需65762.5 kWh;以更换电池一次性计费时,优化模型的结果存在2种策略,即全程不换电池和在第2个充换电站更换一次电池,并且满足在更换电池前累积能耗接近船载电池的总容量,可最大程度利用能量;优化模型能够给出不同电池运营管理模式和用户偏好条件下的最优航速和充换电策略,并且能够应用于充换电站选址决策,对提高纯电动绿色船舶的运营效益具有重要意义。

关键词：船舶工程纯电动绿色船舶长航程航次规划充换电策略选址动态规划多目标优化

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无甲醛浸渍胶膜纸用涂布型装饰原纸的制备及性能

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林业科学 2024年第6期60卷 120-127页

作者：梁敏徐建峰刘如龙玲中国林业科学研究院木材工业研究所北京100091

【目的】针对现有无醛胶黏剂在纸张内部渗透性较差以及一定程度上遮盖原纸色泽和纹理的问题,从装饰原纸性能着手,采用浆内填料加填结合表面颜料化涂布对装饰原纸进行处理,在保证纸张对胶液的渗透性、吸收性前提下,提高纸张的印刷适性和... 详细信息

【目的】针对现有无醛胶黏剂在纸张内部渗透性较差以及一定程度上遮盖原纸色泽和纹理的问题,从装饰原纸性能着手,采用浆内填料加填结合表面颜料化涂布对装饰原纸进行处理,在保证纸张对胶液的渗透性、吸收性前提下,提高纸张的印刷适性和遮盖力,降低无醛胶黏剂对装饰纸饰面效果的影响,为制备适用的无醛装饰纸提供方法。【方法】选用优质阔叶木浆和针叶木浆进行原纸抄造,浆内填料(TiO_(2))含量设为20%、30%和40%,利用二氧化硅(SiO_(2))和聚乙烯醇(PVA)混合液对3种不同加填量的原纸进行涂布、压光整饰得涂布型装饰原纸。采用聚氨酯类无醛胶黏剂对涂布型装饰原纸进行浸渍处理,继而固化和热压贴面。使用扫描电子显微镜(SEM)和动态渗透性测定仪对装饰原纸的表面状态和动态渗透性进行表征测试,应用喷墨打印机对装饰原纸进行印刷打样,通过分光密度计结合相对反差的计算分析装饰原纸的印刷性能,测试分析装饰原纸的抗张强度、平滑度、透气度、吸水性、白度等物理性能以及装饰纸贴面板的表面耐磨性、表面硬度和表面胶合强度等性能。【结果】浆内填料加填量增加会使填料更多填充到原纸结构空隙中,影响胶液在纸张内部的渗透性,致密的表面涂层也会一定程度上降低胶液在纸张内部的渗透性。未涂布原纸的色密度随浆内填料加填量增加而下降,涂布原纸的青、品红、黄、黑色实地密度较未涂布原纸分别提高69.0%、96.2%、45.6%、86.5%,品红、黄、黑3种色别的相对反差均达到标准要求。涂布对装饰原纸的印刷适性起积极作用,填料加填量变化对涂布后装饰原纸印刷适性的影响并不显著;填料加填量增加致使装饰原纸的抗张强度、吸水性下降,平滑度、紧度、白度提高,涂布后装饰原纸较未涂布原纸抗张强度提高52.8%,平滑度提高97.56%,白度变化不明显,不透明度稍有提高;热压后涂布型无醛浸渍胶膜纸的表面耐磨性、硬度和表面胶合强度均达到标准要求。【结论】减少装饰原纸浆内填料加填量,辅以表面涂布方式,能够提高装饰原纸的物理性能以及印刷适性,该方式生产的装饰原纸适用于无醛胶黏剂浸渍,有利于装饰纸无醛化发展。

关键词：无醛胶黏剂装饰原纸颜料化涂布印刷适性动态渗透性

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行李箱盖扭杆弹簧断裂分析与改进

汽车工艺与材料 2024年第3期 47-51页

作者：闵良上海汽车集团股份有限公司乘用车公司上海201804

为了确定行李箱扭杆弹簧断裂机理和原因,对其断口形貌、成分、尺寸、材料强度、微观组织和残余应力进行检测,并结合背景信息进行综合分析。结果表明:行李箱盖扭杆弹簧由于材料强度高、回火不充分、残余应力大,从而在折弯应力集中处发生... 详细信息

为了确定行李箱扭杆弹簧断裂机理和原因,对其断口形貌、成分、尺寸、材料强度、微观组织和残余应力进行检测,并结合背景信息进行综合分析。结果表明:行李箱盖扭杆弹簧由于材料强度高、回火不充分、残余应力大,从而在折弯应力集中处发生高强钢延迟开裂。基于开裂原因,从控制原材料强度和优化去应力回火工艺以降低残余应力2个方面进行改进,最终有效解决了行李箱扭杆弹簧延迟开裂失效问题。

关键词：扭杆弹簧延迟开裂残余应力去应力回火

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新检验规则实施后电梯聚氨酯缓冲器的检验

中国电梯 2024年第7期35卷 29-31页

作者：梁敏福建省特种设备检验研究院漳州分院福建漳州363000

缓冲器性能的安全可靠与否直接关系到电梯的安全运行,检验时经常发现一些缓冲器特别是聚氨酯缓冲器失效的案例。对此,2023版电梯检验规则对聚氨酯缓冲器提出了新要求。介绍了聚氨酯缓冲器的应用,以及2023版检验规则对聚氨酯缓冲器的定... 详细信息

缓冲器性能的安全可靠与否直接关系到电梯的安全运行,检验时经常发现一些缓冲器特别是聚氨酯缓冲器失效的案例。对此,2023版电梯检验规则对聚氨酯缓冲器提出了新要求。介绍了聚氨酯缓冲器的应用,以及2023版检验规则对聚氨酯缓冲器的定期检验要求。分析了聚氨酯缓冲器检验常见的问题,例如聚氨酯缓冲器破损、脱落、压碎,对重越程标识模糊,超出对重越程距离,缓冲器试验失效等,并提出科学规范的整改措施。

关键词：电梯聚氨酯缓冲器检验 TSG T7001—2023 常见问题整改措施

电厂废水处理过程中能源回收与节能技术应用研究

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电力设备管理 2024年第13期 246-248页

作者：梁敏广西华磊新材料有限公司发电厂

电厂废水处理是一项重要的环境保护任务,而能源回收与节能技术在该过程中的应用显得尤为关键。本文通过对电厂废水处理的现状进行深入分析,结合余热回收、生物能源回收、先进氧化技术和膜分离技术等能源回收与节能技术,提出了综合应用... 详细信息

电厂废水处理是一项重要的环境保护任务,而能源回收与节能技术在该过程中的应用显得尤为关键。本文通过对电厂废水处理的现状进行深入分析,结合余热回收、生物能源回收、先进氧化技术和膜分离技术等能源回收与节能技术,提出了综合应用的方案,并在实际案例中进行了效果评估。通过对废水处理过程中能源利用和节能技术的系统研究,旨在为电厂废水处理领域提供科学可行的技术支持,推动废水处理行业的可持续发展。

关键词：电厂废水处理能源回收节能技术