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混合联肢PEC墙结构基于合理失效模式的性能化设计方法研究

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振动与冲击 2024年第7期43卷 266-277,289页

作者：周巧玲赵仕兴苏明周石韵四川省建筑设计研究院有限公司成都610041 西安建筑科技大学土木工程学院西安710055 西安石油大学土木工程学院西安710065

基于性能化设计理念,提出了混合联肢PEC墙结构基于合理失效模式的性能化设计方法:以结构达目标位移时实现合理失效模式作为性能目标,基于能量平衡原理确定结构设计基底剪力,并给出符合失效模式的侧向力分布;依据给定目标塑性耦连比分别... 详细信息

基于性能化设计理念,提出了混合联肢PEC墙结构基于合理失效模式的性能化设计方法:以结构达目标位移时实现合理失效模式作为性能目标,基于能量平衡原理确定结构设计基底剪力,并给出符合失效模式的侧向力分布;依据给定目标塑性耦连比分别求解钢连梁和PEC墙肢底部加强区内力需求;采用塑性设计方法设计钢连梁和PEC墙肢底部加强区截面,采用弹性设计方法设计PEC墙肢非加强区截面,保证结构实现预期性能目标。依据提出的基于合理失效模式的性能化设计方法,设计了12层混合联肢PEC墙算例结构,对其进行Pushover分析和弹塑性动力时程分析,验证了该方法的可行性。基于合理失效模式的性能化设计方法设计的混合联肢PEC墙结构抗震性能良好,地震作用下,各层钢连梁首先剪切屈服耗散能量,然后PEC墙肢底部形成弯曲塑性铰,塑性铰分布及发展过程符合预期,实现了“两阶段耗能体系”设计目标。

关键词：混合联肢墙抗震性能目标位移合理失效模式性能化设计方法

融合星载LiDAR系统GEDI数据与Sentinel-2影像的长江中游洲滩典型禾本科植物高度动态研究

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湖泊科学 2024年第2期36卷 562-574页

作者：石希夏军强周美蓉辛沛武汉大学水资源工程与调度全国重点实验室武汉430072 河海大学水灾害防御全国重点实验室南京210098

植物是大型河流生态系统的重要成分。但受气候变化和人类活动影响,洲滩禾本科植物高度不断发生调整,进而影响洲滩生境和河道防洪安全,故需长期监测。近年来,伴随着星载激光雷达(LiDAR)技术的发展,应用LiDAR卫星数据反演洲滩禾本科植物... 详细信息

植物是大型河流生态系统的重要成分。但受气候变化和人类活动影响,洲滩禾本科植物高度不断发生调整,进而影响洲滩生境和河道防洪安全,故需长期监测。近年来,伴随着星载激光雷达(LiDAR)技术的发展,应用LiDAR卫星数据反演洲滩禾本科植物高度成为一种可能。本文融合新一代星载LiDAR系统GEDI数据与Sentinel-2影像,基于XGBoost算法构建了考虑物候、累积温度与光合有效辐射指标的洲滩典型禾本科植物高度外推模型,同时利用Attention-UNet算法搭建了洪淹区域识别模型。随后以长江中游洲滩为例,探明了星载LiDAR技术在获取洲滩植株高度方面的性能,分析了各指标对模型精度的影响,并初步得出了洲滩典型禾本科植物高度对不同淹没条件的响应模式。主要结论包括:(1)星载LiDAR系统GEDI具有准确探测洲滩植物高度的能力,与无人机航测数据相比RMSE=0.43 m;(2)运用GEDI数据构建禾本科植物高度外推模型时,考虑物候和累积温度等指标可有效提升模型精度,提升幅度为6.8%~10.7%;(3)利用无人机航测数据对模型外推植物高度进行评价,RMSE=0.80 m。同时从模型外推结果中可知,受2020年流域尺度洪水影响,中游各河段平均植物高度下降了0.03~0.24 m;(4)在2020年流域尺度洪水作用下,淹没历时≤10天的洲滩禾本科植物,其次年株高整体呈增长趋势;而淹没历时>10天时,其次年株高平均下降了2.3%~3.1%。此外,对于日均淹没水深与株高的比值>0.95的洲滩,随着比值增加,洪水对禾本科植株高度的负面作用逐步增强。

关键词：星载激光雷达 GEDI 植被高度长江中游洲滩

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氢气在颗粒床内流动不稳定性分析

工程热物理学报 2024年第4期45卷 1156-1161页

作者：吉宇毛晨瑞孙俊郎明刚石磊清华大学核能与新能源技术研究院先进反应堆工程与安全教育部重点实验室北京100084

基于颗粒床反应堆的核热推进技术在深空探测等场景有巨大的优势,氢气在颗粒床内被加热可能会发生流动不稳定现象。理解流动不稳定性发生机理并准确判断不稳定边界对颗粒床反应堆的安全运行有重要的意义。本文对一维颗粒床内的流动过程... 详细信息

基于颗粒床反应堆的核热推进技术在深空探测等场景有巨大的优势,氢气在颗粒床内被加热可能会发生流动不稳定现象。理解流动不稳定性发生机理并准确判断不稳定边界对颗粒床反应堆的安全运行有重要的意义。本文对一维颗粒床内的流动过程进行了理论分析,推导了流动稳定性判据和阻力特性指数表达,并得到了流动稳定性边界。采用计算流体力学的方法对颗粒床内的流动换热过程进行了模拟,依据压降–流量特性曲线同样得到了流动稳定性边界,两者预测在趋势上相似,对颗粒床反应堆核热推进系统的设计提供了重要的参考。

关键词：核热推进颗粒床流动不稳定性理论分析数值模拟

我国国有企业如何响应外生经济波动:不同性质经营主体策略互动的视角

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政治经济学评论 2024年第3期15卷 68-89页

作者：石明明张小军中国人民大学商学院国家发展和改革委员会体制改革综合司

面对供给侧或需求侧短期变动引致的外生经济波动,经济体系内不同所有制类型的经营主体响应存在区别。本文构建了需求侧与供给侧外生冲击情形下政府与不同所有制企业的多阶段动态博弈模型。研究表明,当出现外生重大冲击时,随着最优规制... 详细信息

面对供给侧或需求侧短期变动引致的外生经济波动,经济体系内不同所有制类型的经营主体响应存在区别。本文构建了需求侧与供给侧外生冲击情形下政府与不同所有制企业的多阶段动态博弈模型。研究表明,当出现外生重大冲击时,随着最优规制参数变化,民营企业自发调整产出;而国有企业将承担更多公共功能,以维持总产出相对稳定,从而市场体系内生出两类主体的行为差异。随着外部冲击消退和市场功能修复,最优规制参数相应优化,不同经营主体的最优产出相应进行调整,市场呈现功能性与结构性调整特征。国有企业制度是我国经济治理现代化的基础性、关键性制度。从多种所有制企业行为交互视角出发,应推动建立一种有利于实现整体公共目标的包容性的行为监管框架,并基于公共目标的变化来推进国有企业的功能调整和布局优化。

关键词：外生经济波动国有企业最优规制供给侧结构性改革

维普期刊数据库人大复印报刊资料

Identification of the Genetic Cause for Childhood Disintegrative Disorder by Whole-Exome Sequencing

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Neuroscience Bulletin 2017年第2期33卷 251-254页

作者： Zhu wen Tian-Lin Cheng Da-Zhi yin shi-Bang Sun Zheng Wang Shun-ying Yu yi Zhang Zilong Qiu Ya-Song Du Shanghai Mental Health Center Shanghai Jiao Tong University School of MedicineShanghai 200030China Institute of Neuroscience Center for Excellence in BrainScience and Intelligence TechnologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China School of Life Sciences Peking UniversityBeijing 100871China Euler Genomics Beijing 102206China

Dear Editor,Childhood Disintegrative Disorder（CDD）,also known as Heller’s syndrome and disintegrative psychosis,is a rare progressive neurological disorder,characterized by a late onset（[2 years of age）and regres... 详细信息

关键词： Identi?cation of the Genetic Cause for Childhood Disintegrative Disorder by Whole-Exome Sequencing IIIA CDD

Performance of biological phosphorus removal and characteristics of microbial community in the oxic-settling-anaerobic process by FISH analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第7期9卷 1004-1010页

作者： Jian-fang WANG Qing-liang ZHAO wen-biao JIN shi-jie YOU Jin-na ZHANG School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China Department of Urban and Civil Engineering Harbin Institute of Technology Shenzhen Graduate School Shenzhen 518055 China

Performance of biological phosphorus removal in the oxic-settling-anaerobic(OSA) process was investigated. Cell staining and fluorescent in situ hybridization(FISH) were used to analyze characteristics and microbial community of sludge. Experimental results showed that phosphorus removal efficiency was near 60% and the amount of biological phosphorus accumulation in aerobic sludge of the OSA system was up to 26.9 mg/g. Biological phosphorus removal efficiency was partially inhibited by carbon sources in the continuous OSA system. Contrasted to the OSA system,biological phosphorus removal efficiency was enhanced by 14% and the average total phosphorus(TP) contents of aerobic sludge were increased by 0.36 mg/g when sufficient carbon sources were supplied in batch experiments. Staining methods indicated that about 35% of microorganisms had typical characteristics of phosphorus accumulating organisms(PAOs) . FISH analysis demonstrated that PAOMIX-binding bacteria were predominant microbial communities in the OSA system,which accounted for around 28% of total bacteria.

关键词： Excess sludge reduction Biological phosphorus removal Phosphate accumulating organisms (PAOs) DAPI(4' 6'-diamidino-2-phenyl indol dihydrochloride) Fluorescent in situ hybridization (FISH)

Expression and Activities Experiment of DNA Transduction Motif Based on GAL4 in Pichia Pastoris

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Chemical Research in Chinese Universities 2010年第2期26卷 221-224页

作者： XU Xiao-hong CHI Bao-rong LI Xiao YANG En-cheng GAO Peng LIU Yan JIA Peng KAN shi-fu wen Zong-mei JIN Ning-yi The First Hospital Bethune Faculty of Medical Sciences of Jilin University Changchun 130021 R. P. China Key Laboratory of Genetic Engineering of PLA Academy of Military Medical Sciences Changchun 130062 R. P. China Department of Pharmacy the First Hospital of Harbin Medical University Harbin 150001 P. R. China

The genes encoding DNA-binding domain（BD） designed based on the yeast transcriptional activator GAL4 and protein transduction domain of HIV-1 Tat protein were fused via soft linker peptide sequence, and cloned into yeast expression vector pPIC9k. The resulted plasmid pTG was linearized and transfected into Pichia pastoris strains GS 115 by electroporation. High copies of transformants were obtained with Muts and HIS＋ phenotype identi- fication, PCR amplification and screening of G418. After flask culture and expression induced by methanol, the target protein named TG was well expressed and analyzed by SDS-PAGE and Western blot. Under optimized conditions, the yield of soluble recombinant protein was approximately 39.7 mg/L. DNA binding activity and cell transduction property of TG were analyzed by gel eleetrophoresis and fluorescent microscopy. The results show that the recombinant protein could bind strongly to the plasmid containing upstream activating sequence（UAS）. The cell experiments revealed that TG could deliver the binding plasmid into HEK-293 cells effectively. In summary, the work presented here suggests that TG is specific toward UAS containing plasmid and has the potential for use as nonviral DNA delivery agent.

关键词： Nonviral DNA delivery Yeast transcription activator(GAL4) Cell-penetrating peptide Upstream activating sequence(UAS) Secrete expression Pichia pastoris

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无机填料对水泥固化泥炭土强度的影响

建筑材料学报 2024年第5期27卷 439-445页

作者：史江伟朱浩陈永辉王荣河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210024 中国港湾工程有限责任公司北京100027

通过无侧限抗压强度和扫描电镜试验,研究了无机填料种类和粒径对水泥固化泥炭土强度的影响.结果表明:水泥固化泥炭土强度随着石英砂掺量的增加呈先增加后降低的趋势,20%石英砂掺量下水泥固化泥炭土强度最高;当石英砂粒径d>1.0 mm时,水... 详细信息

通过无侧限抗压强度和扫描电镜试验,研究了无机填料种类和粒径对水泥固化泥炭土强度的影响.结果表明:水泥固化泥炭土强度随着石英砂掺量的增加呈先增加后降低的趋势,20%石英砂掺量下水泥固化泥炭土强度最高;当石英砂粒径d>1.0 mm时,水泥固化泥炭土强度提升有限,而当d<0.5 mm时,水泥固化泥炭土强度提升明显;高岭土颗粒可有效填充泥炭土孔隙,有利于水泥联结无机填料和泥炭土颗粒,且水泥联合高岭土固化泥炭土的强度明显优于水泥联合石英砂;当泥炭土含水率为600%,高岭土掺量从5%增至30%时,28d龄期水泥固化泥炭土强度的增幅为58.5%~116.6%.

关键词：高含水率泥炭土无机填料粒径强度

Abnormalities of interhemispheric functional connectivity in individuals with acute eye pain: a resting-state fMRI study

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International Journal of Ophthalmology(English edition) 2019年第4期12卷 634-639页

作者： Zhi-Zhang Dong Fei-yin Zhu wen-Qing shi Yong-Qiang Shu Lin-Long Chen Qing Yuan Qi Lin Pei-wen Zhu Kang-Cheng Liu You-Lan Min Lei Ye yi Shao Department of Ophthalmology the Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University Department of Ophthalmology the First Affiliated Hospital of Nanchang University Department of Clinical Medicine Queen Mary College of Nanchang University Department of Radiology the First Affiliated Hospital of Nanchang University

AIM: To study the changes of the resting state functional connectivity(rsFC) between acute eye pain(EP) subjects and healthy controls(HCs) in the two hemispheres by using voxel-mirrored homotopic connectivity(VMHC) ***: Totally 20 patients with EP and 20 HCs were enrolled, sex, age, and education were matched, and all subjects were examined by functional magnetic resonance imaging(fMRI) scans at resting-state. The changes of rs FC between the hemispheres were evaluated by the VMHC method according to Gaussian random field(GRF) theory. In order to identify the VMHC, as biomarkers for distinguishing EP and from HC, the receiver operating characteristic curves(ROC) had been analyzed. The relationships were evaluated with Pearson correlation analysis between the mean VMHC signal values and clinical features in these ***: By comparing with health subjects, the significant decreased VMHC values was observed in lingual/calcarine(Brodmann area, BA 30), precentral/postcentral gyrus(PreCG/PosCG; BA 4) and medial frontal gyrus(MFG; BA 8)(false discovery rate corrected <0.01) in the acute EP individuals. The accuracy of area under curve was excellent indicated by the ROC curve analysis of each brain ***: Our study demonstrates preliminary evidence of disrupted interhemispheric rsFC in acute EP in sensorimotor and limbic system and somatosensory cortex, which might give some useful information for understanding the neurological mechanisms in acute EP individuals.

关键词： acute eye pain voxel-mirrored homotopic connectivity functional magnetic resonance imaging resting state