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广西恭城县河谷阶地地貌区岩溶塌陷地质灾害发育特征及形成机理

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地下水 2024年第3期46卷 149-152页

作者：覃莹璐丁凯程亚平范新东桂林理工大学环境科学与工程学院广西桂林541006 桂林水文工程地质勘察院有限公司广西桂林541002

河谷阶地地貌区是广西恭城县岩溶塌陷灾害高发区。本次研究以《恭城瑶族自治县1:5万地质灾害详细调查》项目为依托,综合地形地貌、地质构造、地层岩性、气象条件,分析恭城县河谷阶地地貌区岩溶塌陷的分布规律、影响因素及发育特征,并综... 详细信息

河谷阶地地貌区是广西恭城县岩溶塌陷灾害高发区。本次研究以《恭城瑶族自治县1:5万地质灾害详细调查》项目为依托,综合地形地貌、地质构造、地层岩性、气象条件,分析恭城县河谷阶地地貌区岩溶塌陷的分布规律、影响因素及发育特征,并综合恭城县栗木镇竹凤村某处的塌陷实例,探究河谷阶地地貌区岩溶塌陷成因。研究表明:(1)河谷阶地内42处塌陷均为土洞型塌陷,塌陷坑坑口形状主要有不规则形、圆形两种,个别坑口为方形,坑口长轴方向大致与地下水的流向一致。(2)岩溶塌陷发育诱发因素以自然因素为主,人为因素为辅。从行政区域上看,塌陷发育数量最多的城镇为栗木镇,共有9处塌陷灾害点,占岩溶塌陷灾害总数的22.70%;从规模上看,研究区已发生的岩溶塌陷以小型塌陷为主,只有1处塌陷体积规模大于500 m^(3),规模为100~500 m^(3)的岩溶塌陷有11处,规模为50~100 m^(3)的岩溶塌陷有4处,小于50 m^(3)的塌陷有26处。(3)地形地貌是岩溶塌陷灾害形成的主控因素之一。岩溶塌陷发育受覆盖土层厚度影响,覆盖土层越薄,土洞顶板越薄,越容易发生地面塌陷。其主要分布在D 2t、C 1yt地层中,集中发育于覆盖土层厚度为5~15 m的区域;降雨是诱发区内岩溶塌陷发育的因素之一,但不是决定性因素。研究结果以期为同类地区岩溶塌陷预防和治理提供参考依据。

关键词：河谷阶地岩溶塌陷发育特征地质灾害

抑郁症患者肝-脑功能区rfMRI影像学特征及与其相关性

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中国CT和MRI杂志 2024年第6期22卷 27-30页

作者：陈建单秀红黄海霞丁楷模赵蓓镇江市第五人民医院放射科江苏镇江212004 江苏大学附属人民医院放射科江苏镇江212002 镇江市第五人民医院普通精神科江苏镇江212004 镇江市第五人民医院临床心理科江苏镇江212004

目的探讨抑郁症患者肝-脑功能区静息态功能磁共振成像(rfMRI)影像学特征及与其相关性。方法将2022年11月-2023年7月医院精神科门诊确诊的40例抑郁症发作期患者依据病情严重程度分为轻中度组、重度组,采用rfMRI记录脑区影像学信息,比... 详细信息

目的探讨抑郁症患者肝-脑功能区静息态功能磁共振成像(rfMRI)影像学特征及与其相关性。方法将2022年11月-2023年7月医院精神科门诊确诊的40例抑郁症发作期患者依据病情严重程度分为轻中度组、重度组,采用rfMRI记录脑区影像学信息,比较轻中度组、重度组肝-脑功能区域的影像学特征。同期选取医院进行体检的20名健康志愿者作为对照,比较健康志愿者、抑郁症患者肝-脑功能区域的影像学特征,Pearson相关性分析法评估肝-脑功能区域异常影像学特征值与抑郁症的相关性。结果轻中度组左侧枕中回ReHo值较重度组降低,双侧楔前叶、中扣带回、杏仁核ReHo值较重度组升高,差异具有统计学意义(P<0.05)。健康志愿者左侧枕中回ReHo值较抑郁症患者降低,双侧楔前叶、中扣带回、杏仁核ReHo值较抑郁症患者升高,差异具有统计学意义(P<0.05)。Pearson相关性分析结果显示,肝-脑功能区域中左侧枕中回ReHo值与HAMD-24评分呈正相关(r=0.506,P<0.05),右侧楔前叶、左侧楔前叶、右侧中扣带回、左侧中扣带回、右侧杏仁核、左侧杏仁核ReHo值与HAMD-24评分呈负相关(r=-0.446、-0.452、-0.462、-0.481-、0.520、-0.531,P<0.05)。结论症患者肝-脑功能异常改变的区域分布于楔前叶、枕中回、中扣带回、杏仁核,且随着抑郁症患者病情进展,枕中回ReHo值逐渐升高,楔前叶、中扣带回、杏仁核ReHo值逐渐降低,枕中回、楔前叶、中扣带回、杏仁核区域异常与抑郁症病情具有一定相关性。

关键词：抑郁症肝-脑功能区静息态功能磁共振成像相关性

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Brittleness and fracture mechanism of sintered Dy-doped NdFeB magnets

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Rare Metals 2022年第8期41卷 2688-2692页

作者： Li-Na Zhao Xiao-Li Wang kai-Hong ding Sheng-Li Cui Yong-Cong Sun Mu-Sen Li Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of EducationJinan UniversityJinan250061China Institute of Materials Jiangsu University of Science and TechnologyZhenjiang212003China Yantai Shougang Magnetic Materials Inc Yantai265500China

The brittleness and fracture behaviors of the sintered and the two-stage aged Dy-doped NdFeB magnets were studied by a unique method of acoustic emission testing and Vickers hardness indentation method in this paper.A detailed analysis on the crack propagation mechanism along the grain boundary of the main grain phase(Nd,Dy)_(2)Fe_(14)B was *** comparing the acoustic emission energy count value(E_(n))with the Vickers hardness indentation load(P),it is shown that there is a linear relationship between En and P for both the sintered and the two-stage aged Dy-doped NdFeB *** to the slope of En versus P linear lines,it can be found that the two-stage aged Dy-doped NdFeB magnet is more brittle than the sintered *** is due to that the Ndrich grain boundary phase of the two-stage aged Dy-doped NdFeB magnet is formed as thin film and uniformly distributes around the main grain phase,which plays a significant role in increasing the intrinsic coercive force of the magnet,but decreasing its interface binding ***,the resistance of crack propagation along the grain boundary decreases and the brittleness increases.

关键词： Dy-doped NdFeB magnet Brittleness testing Fracture analysis Acoustic emission testing Vickers hardness indentation

Design and test of 4ZZ-4A2 full-hydraulic self-propelled jujube harvester

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International Journal of Agricultural and Biological Engineering 2018年第4期11卷 104-110页

作者： Wei Fu Zhiyuan Zhang kai ding Weibin Cao Za Kan Junbing Pan Yudong Liu College of Mechanical and Electrical Engineering Shihezi UniversityShihezi 832003XinjiangChina Agricultural Machinery Key Laboratory of Xinjiang Production and Construction Corps Shihezi 832003XinjiangChina

The cultivated area of jujube in Xinjiang has increased rapidly in recent *** the jujube harvest by hand has the shortage of high labor intensity,low efficiency and high labor cost,in addition,the harvesting machinery applying to dwarf and dense planting mode of jujubes is unavailable in *** 4ZZ-4A2 based on the full-hydraulic self-propelled jujube harvester was designed to solve the above *** harvester was mainly composed of a frame,a vibrating device,a jujube collecting and conveying device,an air separation device,a steering system,a hydraulic system and a jujube suction device and was capable of completing vibration,collection,conveying,cleaning and sundries removal work of jujubes through one *** jujubes dropped on the ground were picked up at the same *** AMESim simulation software was adopted to perform simulation analysis on the overall hydraulic *** results showed that the speed of the vibrating motor was stable at about 650 r/min(the corresponding vibration frequency is 10.83 Hz)with the torque of 80 N·m,the speed of the conveyor motor was stable at 77 r/min with the torque of 77 N·m;the speed of the fan motor was stable at 54 r/min with the torque of 53.6 N·m;the speed of the walking motor fluctuated around 100 r/min with the torque of about 1000 N·m;the hydraulic steering system responded rapidly and could satisfy the actual working requirements of the jujube *** jujube garden test results showed that the harvester could reach to the optimum harvesting effect when running at the speed of 0.5 m/*** such speed,the ground jujube picking rate was 45.1%,the tree jujube harvesting rate was 93.2%,the loss rate was 2.9%,and the damage rate was 0.9%.This study can provide theoretical basis and technical support for the jujube harvester.

关键词： harvester jujube hydraulic simulation dwarf and close planting design

基于知识图谱的中文科技文献问答系统构建研究

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中国科技资源导刊 2024年第4期56卷 51-62页

作者：李琳娜丁楷韩红旗王力李艾丹中国科学技术信息研究所北京100038 富媒体数字出版内容组织与知识服务重点实验室北京100038 中国航天科工集团六院情报信息研究中心内蒙古呼和浩特010000

科技文献问答系统能以自然语言对话的方式为用户提供高水平的知识服务。针对语义解析型知识图谱问答系统存在跨领域适应性弱及现有基于深度学习、大模型的问答系统存在结果可解释性差且难以溯源的问题,提出基于句式特点的中文问题分类方... 详细信息

科技文献问答系统能以自然语言对话的方式为用户提供高水平的知识服务。针对语义解析型知识图谱问答系统存在跨领域适应性弱及现有基于深度学习、大模型的问答系统存在结果可解释性差且难以溯源的问题,提出基于句式特点的中文问题分类方法,并设计基于Pipeline方法的中文科技文献问答系统框架。实验结果表明,基于句式特点的问题分类具有不依赖于特定领域的特点且在效果上与基于意图的问题分类基本相当,基于Pipeline的问题解析方法能有效地将问题转化为知识图谱查询语句,从而满足用户对自动问答结果可解释、可溯源的基本需求。

关键词：中文科技文献问答系统知识图谱问题分类体系集成学习

清单式管理在宁夏某多院区医院周工作要点机制中的应用研究

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现代医院 2024年第5期24卷 737-739页

作者：王祥楠刘威丁凡丁恺李娇娇席敏翠王轩获张彦杰宁夏回族自治区人民医院//宁夏医科大学附属自治区人民医院宁夏银川750004 宁夏医科大学人文与管理学院宁夏银川750000

公立医院多院区一体化管理是“国考”与公立医院高质量发展的必然要求。公立医院如何加快分院区同质化建设,实现院区之间信息高度共享,是当前多院区医院管理过程中的热点和难点问题。本文通过宁夏某多院区医院管理实践,探讨多院区医院... 详细信息

公立医院多院区一体化管理是“国考”与公立医院高质量发展的必然要求。公立医院如何加快分院区同质化建设,实现院区之间信息高度共享,是当前多院区医院管理过程中的热点和难点问题。本文通过宁夏某多院区医院管理实践,探讨多院区医院一体化管理面临问题与实现路径,提出通过实施清单式管理运行周工作要点机制五项内容,强化一院多区同质化管理和院区间协同配合,为推进多院区医院一体化治理提供经验借鉴。

关键词：多院区医院清单式管理周工作要点

Anomalous residual austenite formation in root of welding layers of 9% Cr/CrMoV dissimilar welded joint

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Journal of Iron and Steel Research International 2018年第8期25卷 839-846页

作者： kai ding Hui-jun Ji Quan-liang Zhang Xia Liu Peng Wang Xiao-hong Li Ling Zhang Yu-lai Gao State Key Laboratory of Advanced Special Steel State Shanghai Key Laboratory of Advanced FerrometallurgySchool of Materials Science and Engineering Shanghai University Shanghai 200444 China Shanghai Turbine Plant Shanghai Electric Power Generation Equipment Co. Ltd. Shanghai 200240 China

The morphology and distribution of residual austenite in the welded zone of 9% Cr/CrMoV dissimilar welded joint were observed by color metallographic method. Moreover, the details of the distribution, shape, length, length-to-width ratio, and the content of residual austenite in each welding layer were systematically characterized using Image-Pro Plus image analysis software. Different from the techniques such as X-ray diffraction, vibrating sample magnetometer, and electron backscatter diffraction that only involve the content of residual austenite, color metallographic method can offer much more details of the residual austenite, including the location, shape, size, and content, helping evaluate the overall characteristics of the residual austenite produced in the weld. It is interesting that a large amount of block-like and film-like residual austenite was found in the root of each welding layer, while rare at the top. The area fraction of residual austenite located in this zone was approximately 7.5% compared with only 0.5% at the top. In addition, the average area, length, and length-to-width ratio of dispersed residual austenite were quantitatively evaluated to be （4.7 ± 0.6）μm2, （5.1 ±0.6） μm, and （1.1 ± 0.1） μm, respectively. This variety of residual austenite was resulted from the tempering effect by latter welding layer on the previous one and different cooling rates in these two regions during the welding process.

关键词： Residual austenite Color metallographic method Dissimilar welded joint Narrow gap submerged arcwelding Multilayer and multi-pass welding

Outpatient versus inpatient laparoscopic cholecystectomy:a single center clinical analysis

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Hepatobiliary & Pancreatic Diseases International 2010年第1期9卷 60-64页

作者： Ji, Wu ding, kai Li, Ling-Tang Wang, Dan Li, Ning Li, Jie-Shou Nanjing Univ Sch Med Jinling Hosp Res Inst Gen Surg Nanjing 210002 Peoples R China

BACKGROUND: Outpatient laparoscopic cholecystectomy (OPLC) developed in the United States and other developed countries as one of the fast-track surgeries performed in ambulatory centers. However, this practice has not been installed as a routine practice in the major general hospitals and medical centers in China. We designed this case-control study to evaluate the feasibility, benefits, and safety of OPLC. METHODS: Two hundred patients who had received laparoscopic cholecystectomy for various benign gallbladder pathologies from April 2007 to December 2008 at Jinling Hospital of Nanjing University School of Medicine were classified into two groups: OPLC group (100 patients), and control group (100), who were designated for inpatient laparoscopic cholecystectomy (IPLC). Data were collected for age, gender, indications for surgery, American Society of Anesthesiology (ASA) class, operative time, blood loss during surgery, length of hospitalization, and intra- and post-operative complications. The expenses of surgery and in-hospital care were calculated and analyzed. The operative procedures and instrumentation were standardized for laparoscopic cholecystectomy, and the procedures were performed by two attending surgeons specialized in laparoscopic surgery. OPLC was selected according to the standard criteria developed by surgeons in our hospital after review. Reasons for conversion from laparoscopic to open cholecystectomy were recorded and documented. RESULTS: One hundred patients underwent IPLC following the selection criteria for the procedure, and 99% completed the procedure. The median operative time for IPLC was 24.0 minutes, blood loss was 16.2 ml, and the time for resuming liquid then soft diet was 10.7 hours and 22.0 hours, respectively. Only one patient had postoperative urinary infection. The mean hospital stay for IPLC was 58.2 hours, and the cost for surgery and hospitalization was 8770.5 RMB yuan on average. Followup showed that 90% of the patients were

关键词： laparoscopic cholecystectomy outpatient surgery fast-track surgery

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旋转摩擦焊铝-铜接头的显微组织与力学性能

上海金属 2024年第1期46卷 30-37页

作者：陈杰郑革董武峰胡天寒丁凯高玉来永固集团股份有限公司浙江乐清325600 上海大学省部共建高品质特殊钢冶金与制备国家重点实验室上海200444 上海大学先进凝固技术中心上海200444 上海大学材料科学与工程学院上海200444 上海金属零部件绿色再制造工程技术研究中心上海200444

利用旋转摩擦焊工艺实现了1070纯铝与T2纯铜的连接。采用光学显微镜、扫描电子显微镜和电子探针显微分析仪对接头组织和铝-铜界面进行观察分析,并对相同工艺旋转摩擦焊的两块铝-铜接头进行锻压和弯曲试验。结果显示:1号和2号试样在弯曲... 详细信息

利用旋转摩擦焊工艺实现了1070纯铝与T2纯铜的连接。采用光学显微镜、扫描电子显微镜和电子探针显微分析仪对接头组织和铝-铜界面进行观察分析,并对相同工艺旋转摩擦焊的两块铝-铜接头进行锻压和弯曲试验。结果显示:1号和2号试样在弯曲过程中分别断裂于铝-铜界面和铝侧母材。两种试样的铝-铜界面均未观察到明显的金属间化合物。1号和2号试样铝-铜界面处分别存在宽约1.8和2.7μm的元素过渡区。较宽的元素过渡区可提高铝-铜界面结合强度,较窄的元素过渡区是1号试样在弯曲过程中界面断裂的主要原因。因此,应严格控制旋转摩擦焊的工艺稳定性,以提高焊接接头的弯曲性能。

关键词：旋转摩擦焊铝-铜接头微观组织弯曲性能元素过渡区