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基于旋转电弧的窄间隙横焊打底工艺

焊接 2024年第6期 17-25页

作者：张明泽罗雨叶朔朔苏佳毅于俊杰北京石油化工学院能源工程先进连接技术北京市高等学校工程研究中心北京102617

【目的】j型铺设是最适合深水的海底管线铺设和海洋立管安装方法,常采用管道自动焊接装备完成横向环焊缝摆动焊接。针对摆动电弧P-GMAW横焊打底层焊缝成形不对称、背部成形一致性差等问题,提出了基于旋转电弧的窄间隙横焊表面张力过渡(S... 详细信息

【目的】j型铺设是最适合深水的海底管线铺设和海洋立管安装方法,常采用管道自动焊接装备完成横向环焊缝摆动焊接。针对摆动电弧P-GMAW横焊打底层焊缝成形不对称、背部成形一致性差等问题,提出了基于旋转电弧的窄间隙横焊表面张力过渡(Surface tension transfer,STT)打底工艺方法。【方法】以X65管线钢板材对接窄坡口为试验对象,模拟深水立管j型铺设焊接过程。【结果】基于Minitab的田口方法,建立了正交试验模型,通过焊接工艺试验,探究窄间隙横焊STT打底层焊接工艺规范及不同工艺参数组合对焊缝成形的影响规律。【结论】打底层焊缝背部成形一致性好,无未熔合、未焊透等缺陷。

关键词：旋转电弧焊窄间隙横焊打底工艺田口方法正交试验

基于时间滞后集合和实时偏差订正的气温精细化预报研究

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高原山地气象研究 2024年第1期44卷 51-58页

作者：张武龙陈朝平杨康权周威银航四川省气象台成都610072 高原与盆地暴雨旱涝灾害四川省重点实验室成都610072

基于SWC-WINGS模式0.01°×0.01°分辨率的小时2 m气温产品,利用时间滞后集合和实时偏差订正,得到新的逐小时滚动更新的1 km网格气温预报,并基于预报准确率、平均误差、平均绝对误差等指标,对2022年7—8月逐日逐时气温预报结果进行检验... 详细信息

基于SWC-WINGS模式0.01°×0.01°分辨率的小时2 m气温产品,利用时间滞后集合和实时偏差订正,得到新的逐小时滚动更新的1 km网格气温预报,并基于预报准确率、平均误差、平均绝对误差等指标,对2022年7—8月逐日逐时气温预报结果进行检验分析。结果表明:时间滞后集合预报准确率在各时效均高于SWC-WINGS模式最新时次预报,实时偏差订正可明显提升临近时效准确率,1~6 h时效的平均提高率为17.3%。SWC-WINGS模式对于四川地区高、低温预报存在明显的系统性偏差,时间滞后集合对于系统性偏差的改进能力有限,而实时偏差订正可将1 h时效上四川大部分地区低温和高温预报的平均绝对误差分别控制在1℃和2℃以内。针对2022年8月13日四川地区高温天气,时间滞后集合与实时偏差订正集成预报对SWC-WINGS模式预报有较好的订正效果。

关键词： 1公里网格 SWC-WINGS 时间滞后偏差订正

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Loading single lanthanide ion into aluminum molecular rings:water-stable sodalite cage for removal of nuclear-industry anions

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Science China Chemistry 2023年第5期66卷 1384-1393页

作者： Yi-Fan Sun Ya-jie Liu San-Tai Wang Xiao-Yu Liu Chao Ma Wei-Hui Fang jian zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Based on our discovery of neutral aluminum molecular rings,we herein introduce rare earth ions into the center of the ring and reveal their structural *** resulting yoyo-like cationic macrocycles are highly adaptive to guests,creating unusual supramolecular *** first category is stacked with singly oriented rhombohedral channels,which exhibit fast and reversible solvent-triggered molecular motions and structural *** second type of assembly is that yoyo macrocycles and guest molecules form a nested host-guest sodalite cage supramolecular *** is uncommon for guest molecules to be well-defined within cages although caged structures have been *** host-guest interaction discussion reveals the self-adaptation and flexibility of the yoyo *** their good water stability,we investigated their anion exchange *** results show that they have significant exchange capacity for KI/I_(2),ReO_(4)^(-),and MnO_(4)^(-),revealing their potential application in water purification and nuclear waste treatment.

关键词： aluminum molecular ring lanthanide structural adaptability sodalite cage iodine capture

Optical and X-Ray Observations of MAXI j1820+070 During the Early Outburst Phase in 2018:Zooming in the Low Frequency QPOs

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Research in Astronomy and Astrophysics 2022年第4期22卷 106-113页

作者： Dong-Ming Mao Wen-Fei Yu ju-jia zhang Zhen Yan Stefano Rapisarda Xiao-Feng Wang jin-Ming Bai Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650011China Key Laboratory for the Structure and Evolution of Celestial Objects CASKunming 650216China Physics Department Tsinghua UniversityBeijing 100084China Beijing Planetarium Beijing Academy of Sciences and TechnologyBeijing 100044China

We report a further investigation of the optical low frequency quasi periodic oscillations(LF QPOs)detected in the black hole transient MAXI j1820+070 in the 2018 observations with the YFOSC mounted on Lijiang 2.4 m telescope(LjT).In addition,we make use of the Insight-HXMT/HE observations to measure the properties of the quasi-simultaneous X-ray LF QPOs of MAXI j1820+070 on the same *** compared the centroid frequency,the full width at half maximum(FWHM)and the fractional rms of the LF QPOs in both wavelength *** found that the centroid frequency of the optical QPO is at a frequency of 51.58 m Hz,which is consistent with that of the X-ray LF QPO detected on the same day within 1 m *** also found that the FWHM of the optical LF QPO is significantly smaller than that of the X-ray LF QPO,indicating that the optical QPO has a higher *** quasi-simultaneous optical and the X-ray LF QPO at a centroid frequency of about 52 m Hz suggests that the actual mechanisms of these LF QPOs as the Lense-Thirring precession should work in the vicinity of a radius of about 80-117 gravitational radii(R_(g)=GM/c^(2),M is the mass of the black hole)from the black hole if the QPO frequency is related to a proxy of the orbital frequency in the accretion fiow as the Lense-Thirring precession model ***,the apparent higher coherence of the optical QPO favors that it is a more original signal as compared with the X-ray QPO.

关键词： X-ray stars Low mass binary stars X-ray transient sources

基于jT-AR转换模型的非高斯风荷载特性分析

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兰州工业学院学报 2024年第1期31卷 64-70页

作者：孙芳锦阳立云路明璟张大明曾倩桂林理工大学土木与建筑工程学院广西桂林541004 桂林理工大学信息科学与工程学院广西桂林541004 广西岩土力学与岩土工程重点实验室广西桂林541004 辽宁工程技术大学土木工程学院辽宁阜新123000 广西嵌入式技术与智能系统重点实验室广西桂林541004

为了研究大跨度屋盖结构的非高斯风荷载特性,提出一种采用jT-AR转换模型模拟大跨度球面屋盖结构非高斯脉动风压的方法。基于jT变换和AR模型理论进行耦合,提出并构建jT-AR转换模型,模拟生成非高斯脉动风压时程样本数据,与目标功率谱及高... 详细信息

为了研究大跨度屋盖结构的非高斯风荷载特性,提出一种采用jT-AR转换模型模拟大跨度球面屋盖结构非高斯脉动风压的方法。基于jT变换和AR模型理论进行耦合,提出并构建jT-AR转换模型,模拟生成非高斯脉动风压时程样本数据,与目标功率谱及高阶统计量对比验证;通过已有风洞试验结果与作用在大跨度球面屋盖结构表面的非高斯分布特性作对比验证。结果表明:jT-AR转换模型的模拟结果与风洞试验作用在建筑上的非高斯脉动风具有同等作用效应,其模拟仿真结果具备可靠性及普适性。研究结论为大跨度结构抗风设计提供一种新的模拟方法,可代替复杂的风洞试验。

关键词：大跨度屋盖结构 johnson变换 AR自回归模型高阶统计量非高斯脉动风压

基于生信分析与实验验证探讨黄芩素改善癫痫后认知障碍的分子机制

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中医药信息 2024年第6期41卷 1-8,18页

作者：李晨阳赵姣娇郭晗陈思软郝雪南张炜河北医科大学河北石家庄050017

目的:采用网络药理学与实验验证研究黄芩素(Baicalein)对癫痫后认知障碍小鼠模型谷氨酸代谢水平的影响,探讨其防治癫痫后认知障碍的作用机制。方法:基于文献检索与网络药理学分析,应用STRING、DAVID在线平台与Cytoscape 3.8.2软件构建蛋... 详细信息

目的:采用网络药理学与实验验证研究黄芩素(Baicalein)对癫痫后认知障碍小鼠模型谷氨酸代谢水平的影响,探讨其防治癫痫后认知障碍的作用机制。方法:基于文献检索与网络药理学分析,应用STRING、DAVID在线平台与Cytoscape 3.8.2软件构建蛋白-蛋白互作(PPI)网络,京都基因和基因组百科全书(KEGG)信号通路和基因本体论(GO)功能富集分析。利用分子对接技术预测Baicalein与GRIA2、SLC1A1和SLC1A2基因之间的结合力。体内实验:40只雄性C57BL/6j小鼠随机分为Model组、Baicalein组、VPA组和Baicalein+VPA组,每组10只。给予相应干预后检测小鼠海马组织的炎性浸润情况与SLC1A1、SLC1A2的表达水平变化。体外实验:CHO-GRIA2细胞灌注不同剂量的Baicalein,观察其电流变化。结果:PPI网络中发现兴奋性氨基酸载体1(SLC1A1)、兴奋性氨基酸转运体2(SLC1A2)等40个靶点。KEGG与GO富集分析发现谷氨酸能突触、尼古丁成瘾、离子型谷氨酸受体信号通路、AMPA谷氨酸受体活性、突触后致密膜等与谷氨酸强相关的信号通路。分子对接结果表明,Baicalein与GRIA2、SLC1A1、SLC1A2基因具有较强的结合亲和力。给药后,与Model组比较,Baicalein组与Baicalein+VPA组海马组织炎性浸润率显著降低,各给药组SLC1A1与SLC1A2水平显著升高。CHO-GRIA2灌注1、5、10、20、50μmol/L不同剂量的Baicalein后,其抑制作用逐渐增强,IC50为9.353μmol/L。结论:Baicalein可通过上调谷氨酸转运体SLC1A1和SLC1A2的表达,降低GRIA2受体的表达,改善癫痫后认知障碍的海马炎性浸润情况。

关键词：网络药理学黄芩素谷氨酸癫痫后认知障碍谷氨酸转运体

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单纯药物涂层球囊治疗非复杂性冠状动脉大血管原位长病变的安全性及有效性

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实用心电学杂志 2024年第4期33卷 330-335页

作者：李川川詹雅峰欧阳煜张彦程效福建医科大学附属福州市第一医院心血管内科福建福州350009 连江县医院重症医学科福建福州350500

目的对比药物涂层球囊(drug-coated balloon,DCB)与药物洗脱支架(drug-eluting stents,DES)对冠状动脉(简称冠脉)大血管原位长病变的疗效,并探讨DCB作为其常规治疗方式的可能性。方法纳入102例接受冠脉介入治疗且为非复杂性大血管原位... 详细信息

目的对比药物涂层球囊(drug-coated balloon,DCB)与药物洗脱支架(drug-eluting stents,DES)对冠状动脉(简称冠脉)大血管原位长病变的疗效,并探讨DCB作为其常规治疗方式的可能性。方法纳入102例接受冠脉介入治疗且为非复杂性大血管原位长病变的冠心病患者,根据介入策略分为药物球囊治疗组(DCB组)和药物支架治疗组(DES组)。利用定量血流分数(quantitative flow ratio,QFR)技术,分析术前、术后即刻及术后1年随访时的病变特点,比较DCB与DES的疗效。结果(1)两组临床资料差异均无统计学意义。(2)两组患者手术血管位置、单支病变及分叉病变占比、抗血小板药物使用等方面比较,差异均无统计学意义;在预处理方面,DCB组使用棘突球囊占比明显高于DES组(P0.05);术后即刻,DCB组的最小管腔直径[(2.57±0.27)mm vs.(2.95±0.46)mm,P0.05)。(4)随访期间两组主要不良心血管事件(major adverse cardiovascular events,MACE)发生率的差异均无统计学意义(均P>0.05)。结论QFR指导DCB治疗非复杂性冠脉大血管原位长病变的疗效及MACE发生率与DES相仿,但鉴于本研究样本量小,DCB在冠脉大血管原位长病变的临床应用仍需更多证据支持。

关键词：药物涂层球囊冠状动脉大血管病变冠状动脉原位病变冠状动脉长病变定量血流分数

Data analysis guidelines for single‑cell RNA‑seq in biomedical studies and clinical applications

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军事医学研究:英文版 2023年第4期10卷 529-553页

作者： Min Su Tao Pan Qiu‑Zhen Chen Wei‑Wei Zhou Yi Gong Gang Xu Huan‑Yu Yan Si Li Qiao‑Zhen Shi Ya zhang Xiao He Chun‑jie jiang Shi‑Cai Fan Xia Li Murray j.Cairns Xi Wang Yong‑Sheng Li State Key Laboratory of Reproductive Medicine Nanjing Medical UniversityNanjing 211166China College of Biomedical Information and Engineering the First Affiliated Hospital of Hainan Medical UniversityHainan Medical UniversityHaikou 571199HainanChina College of Bioinformatics Science and Technology Harbin Medical UniversityHarbin 150081HeilongjiangChina Department of Immunology Nanjing Medical UniversityNanjing 211166China Department of Laboratory Medicine Women and Children’s Hospital of Chongqing Medical UniversityChongqing 401174China Baylor College of Medicine HoustonTX 77030USA Shenzhen Institute for Advanced Study University of Electronic Science and Technology of ChinaShenzhen 518110GuangdongChina School of Biomedical Sciences and Pharmacy Faculty of Health and Medicinethe University of NewcastleUniversity DriveCallaghanNSW 2308Australia Precision Medicine Research Program Hunter Medical Research InstituteNew Lambton HeightsNSW 2305Australia

The application of single-cell RNA sequencing(scRNA-seq)in biomedical research has advanced our understanding of the pathogenesis of disease and provided valuable insights into new diagnostic and therapeutic *** the expansion of capacity for high-throughput scRNA-seq,including clinical samples,the analysis of these huge volumes of data has become a daunting prospect for researchers entering this ***,we review the workflow for typical scRNA-seq data analysis,covering raw data processing and quality control,basic data analysis applicable for almost all scRNA-seq data sets,and advanced data analysis that should be tailored to specific scientific *** summarizing the current methods for each analysis step,we also provide an online repository of software and wrapped-up scripts to support the *** and caveats are pointed out for some specific analysis tasks and *** hope this resource will be helpful to researchers engaging with scRNA-seq,in particular for emerging clinical applications.

关键词： Single-cell RNA-sequencing(scRNA-seq) Data analysis Biomedical research Clinical applications

A CPK-Based Identity Authentication Scheme for IoT

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Computer Systems Science & Engineering 2022年第3期40卷 1217-1231页

作者： Mingming zhang jiaming Mao Yuanyuan Ma Liangjie Xu Chuanjun Wang Ran Zhao Zhihao Li Lu Chen Wenbing Zhao State Grid jiangsu Electric Power Co. Ltd.Information&Telecommunication BranchNanjing210008China State Grid Key Laboratory of Information&Network Security Institute of Information and CommunicationGlobal Energy Interconnection Research InstituteNanjing210003China Anhui jiyuan Software Co.Ltd SGITGHefei230088China Engineering Research Center of Post Big Data Technology and Application of jiangsu Province Research and Development Center of Post Industry Technology of the State Posts Bureau(Internet of Things Technology)Engineering Research Center of Broadband Wireless Communication Technology of the Ministry of EducationNanjing University of Posts and TelecommunicationsNanjing210003China Department of Electrical Engineering and Computer Science Cleveland State UniversityCleveland44115USA

As the power Internet of Things(IoT)enters the security construction stage,the massive use of perception layer devices urgently requires an identity authentication scheme that considers both security and *** existing public key infrastructure(PKI)-based security authentication scheme is currently difficult to apply in many terminals in *** key distribution and management costs are high,which hinders the development of power IoT security *** Public Key(CPK)technology uses a small number of seeds to generate unlimited public *** is very suitable for identity authentication in the power Internet of *** this paper,we propose a novel identity authentication scheme for power *** scheme combines the physical unclonable function(PUF)with improved CPK technology to achieve mutual identity authentication between power IoT terminals and *** proposed scheme does not require third-party authentication and improves the security of identity authentication for power ***,the scheme reduces the resource consumption of power IoT *** improved CPK algorithm solves the key collision problem,and the third party only needs to save the private key and the public key *** results show that the amount of storage resources occupied in our scheme is *** proposed scheme is more suitable for the power IoT.

关键词： Power Internet of Things terminal equipment identity authentication CPK PUF