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Chinese Journal of Aeronautics 2024年第2期37卷 524-540页

作者： xuan cui Rui ZHAO Min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

Electrically Assisted Forming(EAF)technology has obvious advantages in material *** develop an effective constitutive model considering electrical effects,room temperature and electrically assisted quasi-static uniaxial tensile tests were conducted using ultrathin nickelbased superalloy plates with a thickness of 0.25 *** research focused on the two most widely recognized effects:the Joule thermal and the electric athermal *** mechanism of current action can be divided into two scenarios:one considering the Joule thermal effect only,and the other considering both effects *** basic constitutive models,namely the Modified-Hollomon model and the Johnson-Cook(J-C)model,were selected to be optimized through the classification of two different situations,and four optimized constitutive models were *** was found that the J-C model with simultaneous consideration of the Joule thermal effect and electric athermal effect had the best prediction effect by comparing the results of these four ***,the accuracy of the optimization model was verified by finite element simulation of the electrically assisted stretching optimization *** results show that the constitutive model can effectively predict the temperature effect caused by the Joule heat effect and the athermal effect of current on the material.

关键词： Joule heating Elastoplasticity Plastic deformation Superalloys Constitutive models

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产热脂肪细胞中线粒体代谢适应的调节

中国生物化学与分子生物学报 2024年第7期40卷 897-906页

作者：崔轩施亭潘东宁上海交通大学医学院附属第一人民医院临床研究院上海200080 复旦大学基础医学院代谢分子医学教育部重点实验室上海200030

伴随经济的快速发展和人类生活水平的提高,肥胖、2型糖尿病、非酒精性脂肪肝等各种代谢功能紊乱疾病已成为我国重要的公共卫生问题。产热脂肪细胞含有丰富的线粒体以及解偶联蛋白1(uncoupling protein 1,UCP1),可通过消耗甘油三酯和葡... 详细信息

伴随经济的快速发展和人类生活水平的提高,肥胖、2型糖尿病、非酒精性脂肪肝等各种代谢功能紊乱疾病已成为我国重要的公共卫生问题。产热脂肪细胞含有丰富的线粒体以及解偶联蛋白1(uncoupling protein 1,UCP1),可通过消耗甘油三酯和葡萄糖并以非颤抖性产热的方式来维持哺乳动物核心体温,鉴于产热过程增加体内能量消耗,因此,激活产热脂肪成为防治糖脂代谢紊乱性疾病的重要研究方向。线粒体作为产热脂肪细胞中功能高度保守的细胞器,在产热激活和失活过程中出现代谢适应性的改变以响应产热能力的变化,而产热脂肪细胞中线粒体代谢适应的失调则可能造成产热能力损伤,甚至全身代谢紊乱。本文概述了近年来报道的产热脂肪细胞线粒体多方面的灵活重塑,包括线粒体动力学变化、磷脂和嵴的重塑以及线粒体活性氧水平和氧化应激等方面,全面地总结了相关的调控因子,最后对脂肪细胞产热能力的维持提供了深入的见解,展望了未来有关产热脂肪细胞线粒体的研究方向,以期为开发靶向新药以激活脂肪产热来对抗代谢性疾病提供理论参考。

关键词：产热脂肪组织线粒体动力学蛋白质质量控制嵴线粒体应激

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数字经济对我国物流业高质量发展的影响及机制研究——基于我国31个省级面板数据的实证检验

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物流科技 2024年第10期47卷 85-91页

作者：刘聪崔旋辽宁工程技术大学工商管理学院辽宁葫芦岛125000

文章选取了2015—2020年中国31个省的平衡面板数据,运用基准回归、中介效应回归、双重固定效应模型以及最小二乘法回归研究数字经济对我国物流业高质量发展的影响及影响机制。将样本按照经济发展水平分类,进行分组回归,发现数字经济对... 详细信息

文章选取了2015—2020年中国31个省的平衡面板数据,运用基准回归、中介效应回归、双重固定效应模型以及最小二乘法回归研究数字经济对我国物流业高质量发展的影响及影响机制。将样本按照经济发展水平分类,进行分组回归,发现数字经济对我国物流业高质量发展的影响程度在经济发展水平中等的地区最高,在经济发展水平较高的地区次之,但在经济发展水平较低的地区存在抑制作用。结果表明:数字经济明显促进了物流业的高质量发展,这一结论在进行一系列稳健性检验后仍然成立,且运输水平和地方财政支出是数字经济促进物流业高质量发展的重要作用机制。最后,提出相应的政策建议,为我国物流业高质量发展提供了新思路。

关键词：数字经济技术改进物流业高质量发展运输水平地方财务支出

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钢-ECC组合梁高温冷却后受剪性能研究

建筑结构学报 2024年第2期45卷 38-51页

作者：武芳文买少轩崔璇吴健辉段钧淇长安大学公路学院陕西西安710064

为研究受热温度、冷却方式对钢-高延性水泥基材料(ECC)组合梁高温后受剪性能的影响,通过4根高温后钢-ECC组合梁和1根常温对比组合梁的静力加载试验,分析了钢-ECC组合梁在高温后的裂缝扩展规律、破坏模式、剩余承载力及变形。试验结果表... 详细信息

为研究受热温度、冷却方式对钢-高延性水泥基材料(ECC)组合梁高温后受剪性能的影响,通过4根高温后钢-ECC组合梁和1根常温对比组合梁的静力加载试验,分析了钢-ECC组合梁在高温后的裂缝扩展规律、破坏模式、剩余承载力及变形。试验结果表明:高温作用后,钢-ECC组合梁裂缝呈现多缝开裂、密集分布的特征,随温度升高,裂缝数量增多、宽度增大,湿水冷却后裂缝深度加深;钢-ECC组合梁在常温下及高温后的破坏形态均为剪切破坏,经历200℃高温后钢-ECC组合梁仍具有较好的延性,而当温度高于400℃时,采用湿水冷却后延性下降显著;高温后钢-ECC组合梁承载力降低,200℃内冷却方式对承载力影响较小,400℃时湿水冷却后承载力显著小于自然冷却的,自然冷却和湿水冷却后承载力分别降低8.7%、25.7%;冷却方式对钢-ECC组合梁初始抗剪刚度影响显著,湿水冷却后钢-ECC组合梁初始抗剪刚度提高,而自然冷却后降低。基于ABAQUS软件中瞬态热传导分析模块模拟钢-ECC组合梁的温度场,并采用塑性损伤模型对钢-ECC组合梁进行热-力耦合全过程分析,建立了有限元模型,经比较,模型的预测结果与试验得到的荷载-位移曲线吻合良好。进一步利用有限元模型开展参数分析,发现与自然冷却相比,钢-ECC组合梁湿水冷却后受剪承载力随翼板厚度及强度增加而增长的幅度较小。

关键词：钢-ECC组合梁静力试验受火试验有限元分析受剪性能

干旱地区水盐胁迫对水稻产量构成及稻谷品质的影响研究

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节水灌溉 2024年第1期 33-43页

作者：何进宇刘飞杨杨佳鹤崔烜玮宁夏大学土木与水利工程学院银川750021 旱区现代农业水资源高效利用教育部工程研究中心银川750021 宁夏节水灌溉与水资源调控工程技术研究中心银川750021

针对宁夏引黄灌区传统稻田蒸发量大,盐渍化耕地占地面积广、改良问题难,土地生产力下降等问题。采用水稻滴灌旱作方式,以富源4号(96D10)作为研究对象,通过设置不同土壤水分水平(W1:高100%、W2:中80%及W3:低60%田间持水率)及盐分水平(S1:... 详细信息

针对宁夏引黄灌区传统稻田蒸发量大,盐渍化耕地占地面积广、改良问题难,土地生产力下降等问题。采用水稻滴灌旱作方式,以富源4号(96D10)作为研究对象,通过设置不同土壤水分水平(W1:高100%、W2:中80%及W3:低60%田间持水率)及盐分水平(S1:轻1.2 g/kg、S2:中3.1 g/kg及S3:重5.3 g/kg),探究不同水盐胁迫对水稻产量构成及稻谷品质的影响规律。结果表明,水盐胁迫对水稻产量及品质具有较为显著的影响,其中产量构成因素中,千粒重W3S3较W1S1下降15.89%(2021年)和15.58%(2022年),饱籽率W3S3较W1S1显著下降3.45%(2021年)和4.05%(2022年),单位产量W3S3较W1S1显著下降56.48%(2021年)和63.09%(2022年);品质方面整精米率W3S3较W1S1显著下降12.65%(2021)和13.56%(2022),垩白米率W3S3较W1S1显著上升164.71%(2021)和122.73%(2022),直链淀粉含量W3S3较W1S1显著下降5.97%(2021)和8.99%(2022),蛋白质含量W3S3较W1S1显著上升53.51%(2021)和61.82%(2022)。综合考虑,在节水目标下,采用滴灌旱作方式种植水稻,保持80%田间持水率加轻、中度盐碱化(≤4.0 g/kg)的土壤环境,可以保持较为接近充分灌溉条件下的产量构成水平和较好的稻谷品质水平。该结论可为宁夏引黄灌区盐碱地可持续利用及水稻的节水灌溉适应性研究提供理论依据。

关键词：水盐胁迫水稻滴灌旱作产量构成稻谷品质

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Total-factor energy efficiency of ten major global energy-consuming countries

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Journal of Environmental Sciences 2024年第3期137卷 41-52页

作者： xuan Wang Yonglong Lu Chunci Chen Xiaojie Yi Haotian cui State Key Laboratory of Urban and Regional Ecology Research Centre for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal Wetland Ecosystems College of the Environment and EcologyXiamen UniversityFujian 361102China University of Chinese Academy of Sciences Beijing 100049China

Improving energy efficiency is regarded as a key path to tackling global warming and achieving the Sustainable Development Goals(SDGs).In 2020,the energy consumption of the world's ten major energy-consuming countries accounted for 66.8%of the global *** paper applied data envelopment analysis(DEA)to calculate these ten major energyconsuming countries'total-factor energy efficiency(TFEE)at national and sectoral levels from 2001-2020,and explored the infuencing factors of total-factor energy efficiency with the Tobit regression *** results showed significant difference in the ten countries'energy *** United States and Germany topped the list for total-factor energy efficiency,while China and India were at the ***,the energy efficiency of the industrial subsector has increased significantly over the past two decades,while that of the other subsectors has been relatively *** industrial structure upgrading,per capita GDP,energy consumption structure,and foreign direct investment had significant impacts on energy efficiency with national *** consumption structure and GDP per capita were determinative factors of energy efficiency.

关键词： Total-factor energy efficiency SBM-UN model Major energy-consuming country Carbon emission reduction

Interdecadal change of the linkage between the North Atlantic Oscillation and the tropical cyclone frequency over the western North Pacific

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Science China Earth Sciences 2014年第5期57卷 2148-2155页

作者： ZHOU BoTao cui xuan National Climate Center China Meteorological Administration Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences

The relationship between the North Atlantic Oscillation(NAO) and the tropical cyclone frequency over the western North Pacific(WNPTCF) in summer is investigated by use of observation data. It is found that their linkage appears to have an interdecadal change from weak connection to strong connection. During the period of 1948–1977, the NAO was insignificantly correlated to the WNPTCF. However, during the period of 1980–2009, they were significantly correlated with stronger(weaker) NAO corresponding to more(fewer) tropical cyclones in the western North Pacific. The possible reason for such a different relationship between the NAO and the WNPTCF during the former and latter periods is further analyzed from the perspective of large-scale atmospheric circulations. When the NAO was stronger than normal in the latter period, an anomalous cyclonic circulation prevailed in the lower troposphere of the western North Pacific and the monsoon trough was intensified, concurrent with the eastward-shifting western Pacific subtropical high as well as anomalous low-level convergence and high-level divergence over the western North Pacific. These conditions favor the genesis and development of tropical cyclones, and thus more tropical cyclones appeared over the western North Pacific. In contrast, in the former period, the impact of the NAO on the aforementioned atmospheric circulations became insignificant, thereby weakening its linkage to the WNPTCF. Further study shows that the change of the wave activity flux associated with the NAO during the former and latter periods may account for such an interdecadal shift of the NAO–WNPTCF relationship.

关键词：热带气旋频数西北太平洋北大西洋涛动年代际变化西太平洋副热带高压大气环流气旋性环流 NAO

高分辨T2联合弥散加权成像在直肠癌术前TNM分期评估中的应用价值

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中国肛肠病杂志 2024年第6期44卷 5-7页

作者：李晓维张伯英程秋波轩翠华联勤保障部队第九八九医院磁共振室河南洛阳471000

目的:探讨高分辨磁共振(MR)T2加权成像(T2WI)联合弥散加权成像(DWI)在直肠癌患者术前TNM分期中的应用价值。方法:选取2021年1月至2023年1月,本院收治的102例直肠癌患者,术前均行T2WI和DWI序列扫描,以病理诊断结果为金标准,采用Kappa一... 详细信息

目的:探讨高分辨磁共振(MR)T2加权成像(T2WI)联合弥散加权成像(DWI)在直肠癌患者术前TNM分期中的应用价值。方法:选取2021年1月至2023年1月,本院收治的102例直肠癌患者,术前均行T2WI和DWI序列扫描,以病理诊断结果为金标准,采用Kappa一致性检验法评估T2WI联合DWI行TNM分期的一致性。结果:T2WI联合DWI诊断直肠癌T分期的总准确率为90.20%(92/102),与病理T分期的一致性极好(Kappa值=0.864,P<0.05),其中T1、T2、T3和T4期的灵敏度、特异度及准确度分别为100.00%、98.84%、99.02%;82.35%、95.29%、93.14%;92.00%、93.06%、92.62%;84.21%、100.00%、97.06%。T2WI联合DWI诊断直肠癌N分期的总准确率为79.41%(81/102),与病理N分期的一致性良好(Kappa值=0.705,P<0.05),其中N0、N1、N2期的灵敏度、特异度和准确度分别为87.30%、87.18%、87.25%;56.52%、86.08%、79.41%;81.25%、94.19%、92.16%。结论:T2WI联合DWI诊断直肠癌TNM分期的准确度较高,有助于为临床诊断提供参考依据。

关键词：直肠癌 T2加权成像弥散加权成像 TNM分期

Linkage between the Asian-Pacific Oscillation and the sea surface temperature in the North Pacific

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Chinese Science Bulletin 2010年第12期55卷 1193-1198页

作者： ZHOU BoTao ZHAO Ping cui xuan National Climate Center China Meteorological Administration Beijing 100081 China National Meteorological Information Center China Meteorological Administration Beijing 100081 China National Meteorological Center China Meteorological Administration Beijing 100081 China

The linkage between the Asian-Pacific Oscillation (APO) and the sea surface temperature (SST) in the North Pacific during the summertime (June-August) is preliminarily investigated through an analysis of observed *** is found that APO is significantly and positively correlated to the North Pacific SST,with the correlation coefficient being 0.58 on the interannual timescale during the period 1954-2003,which suggests that a strong (weak) APO corresponds to high (low) SST in the North *** in-phase relationship is well supported by the dynamic and thermal conditions in association with the APO *** APO is in the positive phase,the East Asian westerly jet in the upper troposphere is weakened,and the anomalous anticyclonic circulation prevails in the low-troposphere over the North ***,the negative anomaly of the sensible and latent heat fluxes is predominated in the North Pacific,indicating ocean gets heat flux from the ***,warm water advection northward is strengthened in the North *** of these provide beneficial conditions to warm the North Pacific SST,and thus the SST is increased in this region,and vice versa.

关键词：北太平洋海表温度亚洲涛动太平洋海温年际时间尺度潜热通量海表面温度

深入而细致的另一种视角——难波和彦《建筑家的读书塾》书评

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建筑学报 2023年第7期 116-121页

作者：崔轩清华大学建筑学院北京100084

对《建筑家的读书塾》编著者难波和彦进行简要介绍;对LATs读书会的初衷进一步阐明,暨建筑理论学习的必要性、培养目标和关键命题;对书中涉及庞大知识线索进行系统化梳理,辅之以层次化的“建筑的4层构造”认识框架。并阐释译者对本书著... 详细信息

对《建筑家的读书塾》编著者难波和彦进行简要介绍;对LATs读书会的初衷进一步阐明,暨建筑理论学习的必要性、培养目标和关键命题;对书中涉及庞大知识线索进行系统化梳理,辅之以层次化的“建筑的4层构造”认识框架。并阐释译者对本书著者站位的理解,其所特有的“他山之石可以攻玉”的被传入侧视角,和跳跃于建筑师-理论家思维之间的视角。

关键词：难波和彦建筑理论建筑学教育《建筑家的读书塾》