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基于模态柔度曲率的砖石古塔损伤识别研究

计算力学学报 2024年第3期41卷 534-541页

作者：卢俊龙乔璐张晨李哲田煜西安理工大学土木建筑工程学院西安710048 特变电工新疆新能源股份有限公司西安710061

损伤识别是结构性能评估的有效途径之一,砖石古塔的模态柔度曲率是进行损伤识别的有效参数之一。为研究古塔结构损伤机制与模态柔度曲率的关系,依据兴教寺窥基塔结构模型振动台试验及数值模拟结果,分析周期性荷载作用下塔体动力响应及... 详细信息

损伤识别是结构性能评估的有效途径之一,砖石古塔的模态柔度曲率是进行损伤识别的有效参数之一。为研究古塔结构损伤机制与模态柔度曲率的关系,依据兴教寺窥基塔结构模型振动台试验及数值模拟结果,分析周期性荷载作用下塔体动力响应及破坏特征,建立了塔体损伤程度与模态参数的关系模型。结果表明,古塔结构开裂破坏后,刚度减小,模态柔度曲率增大;数值计算与试验测试所得加速度及频域响应规律一致,塔体模型结构试件的开裂损伤随加载工况增多而持续累积,加载前期损伤参数变化缓慢,而后保持稳定,试验及模拟所得塔体的破坏过程一致。因此,塔体模态柔度曲率变化与古塔结构损伤累积具有一致性,可用于有效可靠识别砖石古塔结构损伤识别。

关键词：砖石古塔损伤识别柔度曲率损伤机制

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超细HMX的微流体结晶调控及高通量制备

火炸药学报 2024年第6期47卷 498-505,I0002页

作者：姜菡雨徐司雨于谨刘博赵双飞王煊军火箭军工程大学智剑实验室陕西西安710025 西安近代化学研究所含能材料全国重点实验室陕西西安710065 南京工业大学生物与制药工程学院江苏南京211816

为了实现含能材料晶体微观结构的精确控制,提升超细含能材料的晶体品质和质量一致性,以HMX为研究对象,搭建微流体结晶平台,研究在微尺度条件下流体的流动特性,开展浓度、流量等反应参数条件对超细HMX晶体颗粒形态的影响研究,并进行了超... 详细信息

为了实现含能材料晶体微观结构的精确控制,提升超细含能材料的晶体品质和质量一致性,以HMX为研究对象,搭建微流体结晶平台,研究在微尺度条件下流体的流动特性,开展浓度、流量等反应参数条件对超细HMX晶体颗粒形态的影响研究,并进行了超细奥克托今(HMX)的批量制备探索。结果表明,与心型芯片相比,涡流型芯片具有更好的传质效果和更薄的边界层效应,更适合于脆性晶体的制备。DMSO作为溶剂时,HMX晶体具有较好的形貌,大小均一,球形度高;当流量比R分别为1、5、10时,HMX的平均粒径分别为8.86、4.14和0.86μm,随着R增大,HMX的粒径逐渐变小,粒径分布变窄;通过改变工艺参数,微流体结晶可实现不同形貌、粒径超细HMX的可控制备;利用多层组合与并联分流的方式,实现了超细HMX的高通量制备,该方法不仅混合效率差异小、产品处理量大且设备整体能耗低,可为高品质窄粒径范围微纳米含能材料的高通量制备提供思路。

关键词：物理化学微流体技术超细HMX 流体模拟结晶调控高通量制备

Calculation of the energy dependence of fission fragments yields and kinetic energy distributions for neutron-induced ^(235)U fission

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Chinese Physics C 2024年第8期48卷 159-169页

作者： Ya-Ning Han zheng Wei Yi-Xuan Wang Dong-Ying Huo Peng-Qi Zhang Ming Li jun Ma Kang Wu Yong-Guang zheng yuan He Zhi-Yong Deng Tian-Zhi Jiang Xiang-Lin Zhuo jin Li yun Zhang yu Zhang jun-Run Wang Xiao-Dong Su Ze-En Yao School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Engineering Research Center for Neutron Application Technology Ministry of EducationLanzhou UniversityLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China School of Mathematics and Statistics Lanzhou UniversityLanzhou 730000China Nuclear Power Institute of China Chengdu 610000China

Fission fragments yields and average total kinetic energy are fundamental nuclear data for nuclear energy applications and the study of nuclear *** fission products,such as ^(95)Zr,^(99)Mo,^(140)Ba,^(144)Ce,and ^(147)Nd,serve as burnup monitors,assessing the number of fissions induced by neutrons on ^(235)***,current experimental data for these fission products worldwide are inconsistent,introducing significant uncertainty into related scientific *** this study,we employed the Potential-driving Model to calculate the independent yields of ^(235)U and evaluate its advantages in such ***,we investigated the energy dependence of independent yields to select important ***,we calculated the cumulative yields of ^(95)Zr,^(99)Mo,^(140)Ba,^(144)Ce,and ^(147)Nd,and compared them with existing literature data to explore the energy dependence of fission products for ^(235)*** the lack of fission product yield data above 14.8 MeV,we extended our calculated incident neutron energy to 20 MeV,aiming to support future scientific *** Geant4 physical model does not consider the influence of incident neutron energy on the average total kinetic energy of fission fragments;thus,we introduced the excitation function of the total kinetic energy of fission fragments recommended by Madland et al.,which effectively describes the experimental data of the average total kinetic energy of fragments formed in ^(235)U *** this paper,we comprehensively discuss the energy dependence of fission product yields and average total kinetic energy.

关键词： ^(235)U(n f) potential-driving model fission yields kinetic energies energy dependence

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面向跨模态检索的查询感知双重对比学习网络

软件学报 2024年第5期35卷 2120-2132页

作者：尹梦冉梁美玉于洋曹晓雯杜军平薛哲北京邮电大学计算机学院(国家示范性软件学院) 北京100876 智能通信软件与多媒体北京市重点实验室(北京邮电大学) 北京100876

近期,跨模态视频语料库时刻检索(VCMR)这一新任务被提出,它的目标是从未分段的视频语料库中检索出与查询语句相对应的一小段视频片段.现有的跨模态视频文本检索工作的关键点在于不同模态特征的对齐和融合,然而,简单地执行跨模态对齐和... 详细信息

近期,跨模态视频语料库时刻检索(VCMR)这一新任务被提出,它的目标是从未分段的视频语料库中检索出与查询语句相对应的一小段视频片段.现有的跨模态视频文本检索工作的关键点在于不同模态特征的对齐和融合,然而,简单地执行跨模态对齐和融合不能确保来自相同模态且语义相似的数据在联合特征空间下保持接近,也未考虑查询语句的语义.为了解决上述问题,提出一种面向多模态视频片段检索的查询感知跨模态双重对比学习网络(QACLN),该网络通过结合模态间和模态内的双重对比学习来获取不同模态数据的统一语义表示.具体地,提出一种查询感知的跨模态语义融合策略,根据感知到的查询语义自适应地融合视频的视觉模态特征和字幕模态特征等多模态特征,获得视频的查询感知多模态联合表示.此外,提出一种面向视频和查询语句的模态间及模态内双重对比学习机制,以增强不同模态的语义对齐和融合,从而提高不同模态数据表示的可分辨性和语义一致性.最后,采用一维卷积边界回归和跨模态语义相似度计算来完成时刻定位和视频检索.大量实验验证表明,所提出的QACLN优于基准方法.

关键词：跨模态语义融合跨模态检索视频时刻定位对比学习

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Review of advanced oxidation processes for treating hospital sewage to achieve decontamination and disinfection

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Chinese Chemical Letters 2024年第1期35卷 140-152页

作者： Si-Ying yu Zhi-Hui Xie Xiaoyu Wu yun-zhe zheng Yang Shi Zhao-Kun Xiong Peng Zhou Yang Liu Chuan-Shu He Zhi-Cheng Pan Kai-jun Wang Bo Lai State Key Laboratory of Hydraulics and Mountain River Engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China Sino-German Centre for Water and Health Research Sichuan UniversityChengdu 610065China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China Water Safety and Water Pollution Control Engineering Technology Research Center in Sichuan Province Haitian Water GroupChengdu 610041China

Hospital sewage contains various harmful pharmaceutical contaminants(e.g.,antibiotics,anti-inflammatory agents,and painkillers)and pathogens(e.g.,bacteria,viruses,and parasites),whose direct discharge into the environment will induce diseases and pose a powerful threat to human health and safety,and environmental *** recent years,advanced oxidation processes(AOPs),particularly photocatalysis,electrocatalysis,and ozone catalysis have been developed as widespread and effective techniques for hospital sewage ***,there is a lack of systematic comparison and review of the prior studies on hospital sewage treatment using AOPs *** review elaborates on the mechanisms,removal efficiencies,and advantages/disadvantages of these AOPs systems for hospital wastewater decontamination and ***,some novel and potential technologies such as photo-electrocatalysis,electro-peroxone,Fenton/Fenton-like,and piezoelectric catalysis are also included and ***,we further summarize and compare the capacity of these AOPs to treat the actual hospital wastewater under the impact of the water matrix and pH,and estimate the economic cost of these technologies for practical ***,the future development directions of AOPs for hospital wastewater decontamination and disinfection have been ***,this study provides a comparison and overview of these AOP systems in an attempt to raise extensive concerns about hospital wastewater decontamination and disinfection technologies and guide researchers to discover the future directions of technologies optimization,which would be a crucial step forward in the field of hospital sewage treatment.

关键词： Hospital sewage treatment Advanced oxidation processes Pharmaceutical contaminants Disinfection Decontamination

The Chinese Society of Clinical Oncology (CSCO): Clinical guidelines for the diagnosis and treatment of gastric cancer, 2023

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Cancer Communications 2024年第1期44卷 127-172页

作者： Feng-Hua Wang Xiao-Tian Zhang Lei Tang Qi Wu Mu-Yan Cai yuan-Fang Li Xiu-Juan Qu Hong Qiu yu-jing Zhang Jie-Er Ying jun Zhang Ling-yu Sun Rong-Bo Lin Chang Wang Hao Liu Miao-zhen Qiu Wen-Long Guan Sheng-Xiang Rao Jia-Fu Ji Yan Xin Wei-Qi Sheng Hui-Mian Xu Zhi-Wei Zhou Ai-Ping Zhou jing jin Xiang-Lin yuan Feng Bi Tian-Shu Liu Han Liang Yan-Qiao Zhang Guo-Xin Li jun Liang Bao-Rui Liu Lin Shen jin Li Rui-Hua Xu Department of Medical Oncology Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhouGuangdongP.R.China Department of Gastrointestinal Oncology Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education)Peking University Cancer HospitalBeijingP.R.China Department of Radiology Peking University Cancer HospitalBeijingP.R.China Department of Endoscopy Center Peking University Cancer HospitalBeijingP.R.China Department of Pathology Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center of Cancer MedicineGuangzhouGuangdongP.R.China Department of Gastric Surgery Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhouGuangdongP.R.China Department of Medical Oncology The First Hospital of China Medical UniversityShenyangLiaoningP.R.China Department of Medical Oncology Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and TechnologyWuhanHubeiP.R.China Department of Radiotherapy Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhouGuangdongP.R.China Department of Medical Oncology Zhejiang Cancer HospitalHangzhouZhejiangP.R.China Department of Medical Oncology Ruijin HospitalShanghai Jiaotong University School of MedicineShanghaiP.R.China Department of Surgical Oncology The Fourth Affiliated Hospital of Harbin Medical UniversityHarbinHeilongjiangP.R.China Department of Medical Oncology Fujian Cancer HospitalFuzhouFujianP.R.China Tumor Center The First Hospital of Jilin UniversityChangchunJilinP.R.China Department of General Surgery Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdongP.R.China Department of Radiology Zhongshan HospitalFudan UniversityShanghaiP.R.China Department of

The 2023 update of the Chinese Society of Clinical Oncology(CSCO)Clini-cal Guidelines for Gastric Cancer focuses on standardizing cancer diagnosis and treatment in China,reflecting the latest advancements in evidence-based medicine,healthcare resource availability,and precision *** updates address the differences in epidemiological characteristics,clinicopatho-logical features,tumor biology,treatment patterns,and drug selections between Eastern and Western gastric cancer *** revisions include a structured template for imaging diagnosis reports,updated standards for molecular marker testing in pathological diagnosis,and an elevated recommendation for neoadju-vant chemotherapy in stage III gastric *** advanced metastatic gastric cancer,the guidelines introduce new recommendations for immunotherapy,anti-angiogenic therapy and targeted drugs,along with updated management strategies for human epidermal growth factor receptor 2(HER2)-positive and deficient DNA mismatch repair(dMMR)/microsatellite instability-high(MSI-H)***,the guidelines offer detailed screening recommendations for hereditary gastric cancer and an appendix listing drug treatment regimens for various stages of gastric *** 2023 CSCO Clinical Guidelines for Gastric Cancer updates are based on both Chinese and international clinical research and expert consensus to enhance their applicability and relevance in clinical practice,particularly in the heterogeneous healthcare landscape of China,while maintaining a commitment to scientific rigor,impartiality,and timely revisions.

关键词： Chinese Society of Clinical Oncology(CSCO) gastric cancer diagnosis surgery neoadjuvant adjuvant radiotherapy chemotherapy targeted therapy immunotherapy

基于极限梯度提升和探地雷达时频特征的水泥路面脱空识别

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同济大学学报（自然科学版） 2024年第1期52卷 104-114,121页

作者：张军姜文涛张云罗婷倚余秋琴杨哲长安大学公路养护装备国家工程实验室陕西西安710064 长安大学道路施工技术与装备教育部重点实验室陕西西安710064 广西北投公路建设投资集团有限公司广西南宁530028 广西交科集团有限公司广西南宁530007

针对探地雷达(GPR)数据解译依赖于人工经验,存在费时费力和主观偏差的问题,提出了基于极限梯度提升(XGBoost)和GPR时频特征的水泥路面脱空识别方法。采用正演模拟、室内试验和现场试验获得了脱空病害数据源,建立含有标签的脱空GPR数据集... 详细信息

针对探地雷达(GPR)数据解译依赖于人工经验,存在费时费力和主观偏差的问题,提出了基于极限梯度提升(XGBoost)和GPR时频特征的水泥路面脱空识别方法。采用正演模拟、室内试验和现场试验获得了脱空病害数据源,建立含有标签的脱空GPR数据集;通过重采样方法统一GPR数据采样频率,并对预处理后的GPR数据进行时频域特征提取,建立了包含18个时域和12个频域特征的数据集。以时频域特征为输入,是否存在脱空病害为输出,采用XGBoost算法构建脱空识别模型,并与随机森林(RF)和人工神经网络(ANN)算法进行对比。结果表明,模型的识别准确率排序为XGBoost(98.10%)>ANN(95.10%)>RF(93.17%),XGBoost模型识别精度最高,并能在实际路面上准确定位脱空区域。

关键词：道路养护探地雷达(GPR) 脱空病害极限梯度提升(XGBoost) 时频域特征

端羟基叠氮呋咱醚氧杂丁烷-HTPE嵌段共聚物合成及内增塑性能

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含能材料 2024年第6期32卷 651-659,I0003页

作者：温昱佳张婧窦金康谭博军刘宁西安近代化学研究所陕西西安710065 氟氮化工资源高效开发与利用国家重点实验室陕西西安710065

针对增塑剂易迁移、渗出进而严重影响聚合物基复合材料物化性能和机械性能的问题,研究通过3-硝基-4-羟基呋咱与3,3-二溴甲基氧杂丁环(BBMO)偶联合成2种新单体3-(4-硝基呋咱-3-氧甲基)-3-溴甲基氧杂环丁烷(BrNFMO)、3,3-二(4-硝基呋咱-3... 详细信息

针对增塑剂易迁移、渗出进而严重影响聚合物基复合材料物化性能和机械性能的问题,研究通过3-硝基-4-羟基呋咱与3,3-二溴甲基氧杂丁环(BBMO)偶联合成2种新单体3-(4-硝基呋咱-3-氧甲基)-3-溴甲基氧杂环丁烷(BrNFMO)、3,3-二(4-硝基呋咱-3-氧甲基)氧杂环丁烷(BNFMO),以端羟基聚醚(HTPE)为大分子引发剂,在三氟化硼乙醚催化下分别与BrNFMO、BNFMO以及对照组BBMO共聚后叠氮化,制备得到三种内增塑嵌段共聚物,对其进行结构、热分解行为、内增塑性能测试,并对所设计目标共聚单元进行量化计算以评估其爆轰性能。最后对共聚工艺进行了优化,通过“假活性”聚合策略对引入嵌段的程度进行控制。结果表明,该系列新型含能共聚单元具有优于现有叠氮基氧杂环丁烷单体的能量水平。与直接将叠氮基团引入聚合物相比,通过呋咱醚桥联结构将叠氮基团进行引入能够通过内增塑策略获得具有更低玻璃化转变温度T_(g)与黏度的含能共聚物(T_(g)可降低5.27℃,黏度可降低4.90 Pa·s),其热稳定性也得到了提高(T_(d)可提高7.3℃)。

关键词：呋咱含能聚合物阳离子开环聚合含能粘合剂热稳定性内增塑

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岩石圈磁场与地质构造和地震活动性之间的关系--以漾濞地震为例

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地震地质 2024年第2期46卷 449-461页

作者：陈政宇倪喆周思远金云华杨薪俊云南省地震局昆明650224

文中利用2018-2021年漾濞及周边地区的地磁矢量数据,构建了5期岩石圈磁场曲面样条模型,并计算得到相邻期的岩石圈磁场变化。在此基础上,分析了岩石圈磁场的空间分布与区域地质构造和历史地震震中的对应关系,并针对漾濞M_(S)6.4地震,研... 详细信息

文中利用2018-2021年漾濞及周边地区的地磁矢量数据,构建了5期岩石圈磁场曲面样条模型,并计算得到相邻期的岩石圈磁场变化。在此基础上,分析了岩石圈磁场的空间分布与区域地质构造和历史地震震中的对应关系,并针对漾濞M_(S)6.4地震,研究了磁偏角和地磁总强度在震前、震后的磁场变化特征。研究发现:岩石圈磁场的空间展布能够反映地壳块体构造特征和主要断裂走向,同时也与地震活动的分布存在相关性。通过对比分析历史地震的震中分布发现,地震多发生在弱磁区,尤其是磁异常零值区附近,且地震震中分布偏向于高梯度带上。漾濞M_(S)6.4地震发生前后,震中附近的岩石圈磁场发生显著变化,震前、震中持续位于磁偏角负变化区,震后则位于正变化区,且震中位于震前一年磁偏角变化的零变线附近;震前研究区内相邻期地磁总强度的正负变化大致均衡,随后逐渐演变为整个研究区均呈负值,而地震后研究区又恢复了正负变化大致均衡的分布。

关键词：漾濞地震岩石圈磁场震磁异常

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