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基于焊点表面图像处理的点焊质量监测

焊接学报 2006年第12期27卷 57-60,64页

作者：张鹏贤陈剑虹杜文江兰州理工大学有色金属合金省部共建教育部重点实验室兰州730050

以采集的电阻点焊接头表面的数字图像作为信息源,探索了一种新的点焊质量无损监测方法。首先,通过图像特征分析,焊点表面图像被划分为4个环形特征区域,提取环形特征区域面积作为表征焊点质量的特征参数。其次,根据特征区域面积与焊点抗... 详细信息

以采集的电阻点焊接头表面的数字图像作为信息源,探索了一种新的点焊质量无损监测方法。首先,通过图像特征分析,焊点表面图像被划分为4个环形特征区域,提取环形特征区域面积作为表征焊点质量的特征参数。其次,根据特征区域面积与焊点抗剪强度的相关性分析结果,选择了相关性显著的3个特征参数作为输入向量,焊点抗剪强度作为输出向量,建立了点焊质量的RBF神经网络监测模型。仿真分析和验证结果表明,基于焊点表面图像特征信息处理监测点焊质量的方法是可行的。

关键词：电阻点焊焊点表面图像图像处理 RBF神经网络质量监测

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硅铝合金真空热法还原硼镁石矿实验研究

东北大学学报（自然科学版） 2008年第10期29卷 1455-1458页

作者：徐冬 *** 张显鹏李杰程恩庆东北大学材料与冶金学院辽宁沈阳110004 E-mail: xu-dong444 辽宁省镁资源保护办公室辽宁沈阳110001

为了解决低品位硼镁石矿的合理利用问题,首次以硅铝合金为还原剂,应用真空热法还原原理将煅烧后矿石中的游离氧化镁还原为金属镁.正交实验结果表明,最佳还原条件为:还原温度1 453 K、还原时间2.0 h、制团压力35 MPa、还原剂过量系数10%... 详细信息

为了解决低品位硼镁石矿的合理利用问题,首次以硅铝合金为还原剂,应用真空热法还原原理将煅烧后矿石中的游离氧化镁还原为金属镁.正交实验结果表明,最佳还原条件为:还原温度1 453 K、还原时间2.0 h、制团压力35 MPa、还原剂过量系数10%,该条件下镁的还原率可达到63.7%.得到的还原余料可用做生产无碱玻璃球的原料.该工艺对环境无污染,为硼镁石矿的综合利用开辟了一条新途径.

关键词：硼镁石矿正交实验真空热法还原硅铝合金无碱玻璃球

Differences in Toxicokinetics and Maternal Transfer between Lipophilic and Proteinophilic Halogenated Organic Pollutants in Laying Hens

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Environment & Health 2024年第10期2卷 712-720页

作者： Xiao-Jun Luo Qun-Jie Feng Chu-Hong Zhu Xi Chen peng-peng Chen Yan-Hong Zeng Bi-xian Mai State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Resources Utilization and Protection and Guangdong-Hong Kong-Macao Joint Laboratory for Environmental Pollution and Control Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640P.R.China State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Resources Utilization and Protection Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

In this study,we conducted exposure experiments on egg-laying hens to explore the toxicokinetics and maternal transfer characteristics of lipophilic and proteinophilic halogenated organic pollutants(HOPs).The lipophilic HOPs included polychlorinated biphenyls(PCBs),polybrominated diphenyl ethers(PBDEs),and dechlorane plus(DPs),while the proteinophilic HOPs included perfluorocarboxylic acids(PFCAs).The results revealed that most of lipophilic HOPs exhibit lower depuration rate(kd)than *** kd of lipophilic HOPs correlated with the octanol−water partition coefficient(log KOW)values in a V-shaped curve,whereas that of PFCAs correlated with the protein−water partition coefficient(log KPW)values in an inverted V-shaped *** depuration rate,rather than the uptake rate,was a leading factor in determining the bioaccumulation potential of HOPs in *** the dominant factors determining the tissue distribution of the two types of compounds were explicit(fats vs phospholipids),chemical-specific tissue distribution was still *** egg-maternal concentration ratio was dependent on the exposure status,concentration,and maternal tissue *** a single maternal tissue may not be an appropriate method for assessing chemical maternal transfer *** have a greater maternal transfer potential(>80%of the total body burden)than lipophilic HOPs(approximately 30%for BDE209 and DPs,and less than 10%for the others).Their lipophilic and partly proteinophilic nature makes the toxicokinetics and maternal transfer characteristics of BDE209 and DPs different from those of other lipophilic *** findings are crucial for enhancing our understanding of the behavior and fate of HOPs in egg-laying hens.

关键词： halogenated organic pollutants laying hens toxicokinetic maternal transfer

The only purple-flower species in Actaea *** pollinated by a hornet

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Journal of Plant Ecology 2024年第4期17卷 181-196页

作者： Lin-Feng Qiu Jiu-Dong zhang Ying Li Xiao-Ying Liu Dan-Qing zhang Long Huang Ya-peng Yang Shi-Yu Wang Yue-Yi Li Zi-Wei Ma Jie Sui Lin Wang Xiao-Fen Che xian-Hua Tian Yi Ren Jian-Qiang zhang National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China College of Life SciencesShaanxi Normal UniversityXi’an 710119China Key Laboratory of Medicinal Plant Resource and Natural Pharmaceutical Chemistry of Ministry of Education Shaanxi Normal UniversityXi’an 710119China College of Biological and Environmental Engineering Xi’an UniversityXi’an 710065China

Examining the pollination biology of plant species is not only crucial for enhancing our understanding of their reproductive biology,but also essential for elucidating their adaptation and evolutionary ***,we investigated the breeding system and pollination biology of two closely related species in *** flower of *** is unique in the genus with purple and chartaceous(paper-like)sepals,fewer stamens with yellow anthers and purple *** three seasons of field observation and exclusion experiments,we determined that *** was primarily pollinated by a hornet species,Vespa bicolor,which also served as the most efficient *** contrast,*** was primarily pollinated by large *** purpurea exhibited a significantly higher cumulative nectar volume than ***,which could be a crucial factor in attracting ***.A control experiment further demonstrated that removing the nectar leaf(petal)significantly decreased the visiting frequency of *** system studies revealed that both species were self-compatible,yet they primarily underwent outcrossing in natural *** study presents a compelling case of possible pollinator shift in *** accompanied by morphological divergence.A more in-depth investigation of this system would offer crucial insights into the extent to which pollinators are involved in the plant speciation process and whether they contribute to reproductive isolation between closely related species.

关键词： Actaea purpurea Actaea japonica breeding system pollinator shift speciation Vespa bicolor

Effect of salinization on soil properties and mechanisms beneficial to microorganisms in salinized soil remediation-a review

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Research in Cold and Arid Regions 2024年第3期16卷 121-128页

作者： Jing Pan xian Xue CuiHua Huang QuanGang You PingLin Guo RuiQi Yang FuWen Da ZhenWei Duan Fei peng Drylands Salinization Research Station Key Laboratory of Desert and DesertificationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Sciences Beijing 100049China College of Urban Environment Lanzhou City UniversityLanzhouGansu 730070China College of Geographical Science Qinghai Normal UniversityXiningQinghai 810016China Wuwei Academy of Agricultural Sciences WuweiGansu 733000China Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands LanzhouGansu 730070China

Salinized soil is an important reserved arable land resource in *** management and utilization of salinized soil can safeguard the current size of arable land and a stable grain *** accumulation will lead to the deterioration of soil properties,destroy soil production potential and damage soil ecological functions,which in turn will threaten global water and soil resources and food security,and affect sustainable socio-economic *** are important components of salinized *** remediation is an important research tool in improving salinized soil and is key to realizing sustainable development of agriculture and the *** about the impact of salinization on soil properties and measures using microorganisms in remediation of salinized soil has grown over ***,the mechanisms governing these impacts and the ecological principles for microbial remediation are ***,it is imperative to summarize the effects of salinization on soil physical,chemical,and microbial properties,and then review the related mechanisms of halophilic and halotolerant microorganisms in salinized soil remediation via direct and indirect *** stability,persistence,and safety of the microbial remediation effect is also highlighted in this review to further promote the application of microbial remediation in salinized *** objective of this review is to provide reference and theoretical support for the improvement and utilization of salinized soil.

关键词： Salinized soil Microbial remediation Halophilic and halotolerant microorganisms Soil properties

Standard-definition White-light,High-definition White-light versus Narrow-band Imaging Endoscopy for Detecting Colorectal Adenomas:A Multicenter Randomized Controlled Trial

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Current Medical Science 2024年第3期44卷 554-560页

作者： Chang-wei DUAN Hui-hong ZHAI Hui XIE xian-zong MA Dong-liang YU Lang YANG Xin WANG Yu-fen TANG Jie zhang Hui SU Jian-qiu SHENG Jun-feng XU peng JIN Chinese PLA General Hospital and Medical School Beijing100853China Department of Gastroenterology Xuanwu HospitalCapital Medical UniversityBeijing100053China Department of Gastroenterology The Seventh Medical Center of Chinese PLA General HospitalBeijing100700China Senior Department of Gastroenterology The First Medical Center of Chinese PLA General HospitalBeijing100853China

Objective This study aimed to compare the performance of standard-definition white-light endoscopy(SD-WL),high-definition white-light endoscopy(HD-WL),and high-definition narrow-band imaging(HD-NBI)in detecting colorectal lesions in the Chinese *** This was a multicenter,single-blind,randomized,controlled trial with a non-inferiority *** undergoing endoscopy for physical examination,screening,and surveillance were enrolled from July 2017 to December *** primary outcome measure was the adenoma detection rate(ADR),defined as the proportion of patients with at least one adenoma *** associated factors for detecting adenomas were assessed using univariate and multivariate logistic *** Out of 653 eligible patients enrolled,data from 596 patients were *** ADRs were 34.5%in the SD-WL group,33.5%in the HD-WL group,and 37.5%in the HD-NBI group(P=0.72).The advanced neoplasm detection rates(ANDRs)in the three arms were 17.1%,15.5%,and 10.4%(P=0.17).No significant differences were found between the SD group and HD group regarding ADR or ANDR(ADR:34.5%vs.35.6%,P=0.79;ANDR:17.1%vs.13.0%,P=0.16,respectively).Similar results were observed between the HD-WL group and HD-NBI group(ADR:33.5%vs.37.7%,P=0.45;ANDR:15.5%vs.10.4%,P=0.18,respectively).In the univariate and multivariate logistic regression analyses,neither HD-WL nor HD-NBI led to a significant difference in overall adenoma detection compared to SD-WL(HD-WL:OR 0.91,P=0.69;HD-NBI:OR 1.15,P=0.80).Conclusion HD-NBI and HD-WL are comparable to SD-WL for overall adenoma detection among Chinese *** can be concluded that HD-NBI or HD-WL is not superior to SD-WL,but more effective instruction may be needed to guide the selection of different endoscopic methods in the *** study’s conclusions may aid in the efficient allocation and utilization of limited colonoscopy resources,especially advanced imaging technologies.

关键词： standard-definition white-light endoscopy high-definition white-light endoscopy narrow-band imaging colonoscopy colorectal cancer screening adenoma detection rate

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基于信号特征提取的电阻点焊质量在线评判

焊接学报 2005年第9期26卷 52-57页

作者：张鹏贤张宏杰马跃洲陈剑虹兰州理工大学材料科学与工程学院兰州730050

以焊点接头强度作为焊点质量评判的指标,通过对点焊过程焊接电流、动态电阻、电极位移信号的同步采集和特征分析,提取若干特征参量监测点焊过程,依据特征参量与焊点接头抗剪强度间的相关分析结果,选取来自不同监测信号的7个特征参量建... 详细信息

以焊点接头强度作为焊点质量评判的指标,通过对点焊过程焊接电流、动态电阻、电极位移信号的同步采集和特征分析,提取若干特征参量监测点焊过程,依据特征参量与焊点接头抗剪强度间的相关分析结果,选取来自不同监测信号的7个特征参量建立了表征点焊过程的特征模式,并将此转化为计算机可以识别的模式矩阵,同时以焊接电流参数为模式分类的依据,建立不同模式矩阵类别和焊点接头抗剪强度之间的映射,将模式矩阵作为Hopfield神经网络的记忆样本存储于网络,利用网络联想记忆的功能实现对未知样本点焊过程的模式识别,进而实现点焊质量的评判。网络测试结果表明,利用Hopfield网络进行焊点质量在线评判可以得到满意的效果。

关键词：电阻点焊特征提取数据泛化 Hopfield神经网络模式识别

基于白光中子源的^(197)Au中子辐射俘获截面测量及共振参数分析

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物理学报 2024年第7期73卷 104-113页

作者：罗淏天张奇玮栾广源王晓宇邹翀任杰阮锡超贺国珠鲍杰孙琪黄翰雄王朝辉吴鸿毅顾旻皓余滔解立坤陈永浩安琪白怀勇鲍煜曹平陈昊磊陈琪萍陈裕凯陈朕崔增琪樊瑞睿封常青高可庆韩长材韩子杰何泳成洪杨黄蔚玲黄锡汝季筱璐吉旭阳蒋伟江浩雨姜智杰敬罕涛康玲康明涛李波李超李嘉雯李论李强李晓李样刘荣刘树彬刘星言穆奇丽宁常军齐斌斌任智洲宋英鹏宋朝晖孙虹孙康孙晓阳孙志嘉谭志新唐洪庆唐靖宇唐新懿田斌斌王丽娇王鹏程王琦王涛峰文杰温中伟吴青彪吴晓光吴煊羊奕伟易晗于莉于永积张国辉张林浩张显鹏张玉亮张志永赵豫斌周路平周祖英朱丹阳朱科军朱鹏朱兴华中国原子能科学研究院核数据重点实验室北京102413 中国科学院高能物理研究所北京100049 散裂中子源科学中心东莞523803 核探测与核电子学国家重点实验室北京100049 中国科学技术大学近代物理系核探测与核电子学国家重点实验室合肥230026 北京大学物理学院核物理与核技术国家重点实验室北京100871 中国工程物理研究院核物理与化学研究所绵阳621900 西北核技术研究院西安710024 中国科学院大学北京100049 中国科学技术大学工程与应用物理系合肥230026 北京航空航天大学物理学院北京100083 华能山东石岛湾核电有限公司荣成264312

中子辐射俘获反应在反应堆运行、核装置设计及核天体物理研究中起重要的作用.4πBaF_(2)探测装置有着高时间分辨能力、低中子灵敏度、高探测效率等优点,适合开展中子辐射俘获反应截面数据的测量.中国原子能科学研究院核数据重点实验室... 详细信息

中子辐射俘获反应在反应堆运行、核装置设计及核天体物理研究中起重要的作用.4πBaF_(2)探测装置有着高时间分辨能力、低中子灵敏度、高探测效率等优点,适合开展中子辐射俘获反应截面数据的测量.中国原子能科学研究院核数据重点实验室建立了伽马全吸收装置(Gamma total absorption facility,GTAF),该装置用28块六棱BaF_(2)晶体和12块五棱BaF_(2)晶体构成了外径25 cm,内径10 cm的球壳,覆盖了95.2%的立体角.利用GTAF在中国散裂中子源Back-n束线上,测量了197Au(n,γ)的反应截面数据.测量数据通过能量筛选、PSD方法、晶体多重性筛选进行了初步本底扣除,随后结合对^(nat)C及空样品的测量数据对本底进行了分析及扣除,获得了197Au俘获反应的产额,利用SAMMY程序拟合得到了^(197)Au在1—100 e V的共振能量、中子共振宽度和伽马共振宽度参数.实验测量结果与ENDF/B-VIII.0数据库符合良好,其共振参数存在一定差异,分析原因可能与GTAF能量分辨率、Back-n的中子能谱测量精度、以及实验本底扣除方法相关,这也是下一步工作的重点.

关键词：中子辐射俘获截面共振参数白光中子源伽马全吸收装置

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Metal-N_(4)model single‐atom catalyst with electroneutral quadri‐pyridine macrocyclic ligand for CO_(2)electroreduction

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Carbon Energy 2024年第8期6卷 122-133页

作者： Jian‐Zhao peng Yin‐Long Li Yao‐Ti Cheng Fu‐Zhi Li Bo Cao Qing Wang xian Yue Guo‐Tao Lai Yang‐Gang Wang Jun Gu Department of Chemistry Southern University of Science and TechnologyShenzhenGuangdongChina Institute for Catalysis Hokkaido UniversitySapporoJapan

Metal–N–C single‐atom catalysts,mostly prepared from pyrolysis of metalorganic precursors,are widely used in heterogeneous *** metal sites with diverse local structures coexist in this type of material and it is challenging to characterize the local structure,a reliable structure–property relationship is difficult to *** macrocyclic complexes adsorbed on carbon support are well‐defined models to mimic the singleatom ***–N_(4)site with four electroneutral pyridine‐type ligands embedded in a graphene layer is the most commonly proposed structure of the active site of single‐atom catalysts,but its molecular counterpart has not been *** this work,we synthesized the conjugated macrocyclic complexes with a metal center(Co,Fe,or Ni)coordinated with four electroneutral pyridinic ligands as model catalysts for CO_(2)*** comparison,the complexes with anionic quadri‐pyridine macrocyclic ligand were also *** Co complex with the electroneutral ligand expressed a turnover frequency of CO formation more than an order of magnitude higher than that of the Co complex with the anionic *** ab initio molecular dynamics simulations based on the well‐defined structures of the model catalysts indicate that the Co complex with the electroneutral ligand possesses a stronger ability to mediate electron transfer from carbon to CO_(2).

关键词： ab initio molecular dynamics CO_(2)reduction electrocatalysis model catalyst single‐atom catalyst