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某管道杂散电流干扰影响及防护效果评价

全面腐蚀控制 2024年第3期38卷 1-6,87页

作者：李强林杜建王朋钱文振贾明贵孙彩云朱传涛山东省天然气管道有限责任公司山东济南250032 中石化石油工程设计有限公司山东东营257026

针对某管道面临的杂散电流干扰影响,通过开展现场长周期检测评价、临时馈电试验、设置腐蚀失重试片等方法,明确杂散电流干扰的影响范围和影响程度,掌握管道沿线电位偏移、周期性变化、试片腐蚀速率及特征等规律,制定相应的缓解方案,并... 详细信息

针对某管道面临的杂散电流干扰影响,通过开展现场长周期检测评价、临时馈电试验、设置腐蚀失重试片等方法,明确杂散电流干扰的影响范围和影响程度,掌握管道沿线电位偏移、周期性变化、试片腐蚀速率及特征等规律,制定相应的缓解方案,并验证缓解措施的有效性。为长输油气管道受杂散电流干扰影响的防护治理提供参考经验。

关键词：长输管道杂散电流干扰缓解措施

浙江省杭州市雷竹虫瘿昆虫的物种及生物学特性

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竹子学报 2024年第1期43卷 50-56页

作者：孙娇娇耿显胜王文鹏楼科勋华克达汪晓杰杭州市富阳区农业林业资源保护中心浙江杭州311400 中国林业科学研究院亚热带林业研究所浙江杭州311400 杭州市富阳区农技推广中心浙江杭州311400 杭州市富阳区常绿镇区域发展与治理中心浙江杭州311417

【目的】调查浙江省杭州市雷竹(Phyllostachys violascens‘Prevernalis’)林造瘿害虫的危害情况,研究雷竹虫瘿内昆虫的生物学特性,为发展高效的造瘿害虫防控技术提供基础。【方法】采用抽样法调查造瘿害虫的危害情况;采用室内饲养法和... 详细信息

【目的】调查浙江省杭州市雷竹(Phyllostachys violascens‘Prevernalis’)林造瘿害虫的危害情况,研究雷竹虫瘿内昆虫的生物学特性,为发展高效的造瘿害虫防控技术提供基础。【方法】采用抽样法调查造瘿害虫的危害情况;采用室内饲养法和生物测定法研究雷竹虫瘿内昆虫的物种组成、数量特征、羽化出孔节律等生物学特性。【结果】造瘿害虫的有虫株率在85.00%以上,每盘枝条的平均虫口在18.35头以上。雷竹虫瘿内有竹泰广肩小蜂(Tetramesa bambusae)、刚竹泰广肩小蜂(***)、竹瘿广肩小蜂(Aiolomorphus rhopaloides)和刚竹瘿蚊(Procystiphora sp.)4种造瘿害虫,竹泰广肩小蜂和刚竹泰广肩小蜂的个体数量占造瘿害虫总数的96.20%,是雷竹上最主要的造瘿害虫;竹泰广肩小蜂的初始卵量多于刚竹泰广肩小蜂,并且其卵体也更大,但竹泰广肩小蜂雌成虫的寿命短于刚竹泰广肩小蜂。雷竹虫瘿内有栗瘿旋小蜂(Eupelmus urozonus)、纹黄枝瘿金小蜂(Homoporus japonicas)、中国枝瘿金小蜂(***)、具点刻腹小蜂(Ormyrus punctiger)、黄色食瘿广肩小蜂(Sycophila flava)、黄腹长角金小蜂(Norbanus longifasciatus)和竹瘿长角金小蜂(***)7种寄生蜂,个体数量最多是栗瘿旋小蜂。【结论】竹泰广肩小蜂和刚竹泰广肩小蜂是雷竹林主要的造瘿害虫;刚竹瘿蚊为浙江省新报道的竹子造瘿害虫。雷竹虫瘿内寄生蜂的数量多,这些寄生蜂是造瘿害虫种群抑制的重要生物因子,应加以保护和利用。

关键词：雷竹虫瘿造瘿害虫寄生蜂

Acellular nerve xenografts based on supercritical extraction technology for repairing long-distance sciatic nerve defects in rats

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Bioactive Materials 2022年第12期7卷 300-320页

作者： Shuai Wei Qian Hu Jianxiong Ma Xiu Dai Yu sun Gonghai Han Haoye Meng Wenjing Xu Lei Zhang Xinlong Ma Jiang peng Yu Wang Tianjin Hospital Tianjin UniversityNo.406 Jiefang South RoadHexi DistrictTianjin300211China Institute of Orthopedics The First Medical CenterChinese PLA General HospitalBeijing Key Lab of Regenerative Medicine in OrthopedicsKey Laboratory of Musculoskeletal Trauma and War Injuries PLANo.28 Fuxing RoadHaidian DistrictBeijing 100853China Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education Neural Regeneration Co-Innovation Center of Jiangsu ProvinceNantong UniversityNo.19 Qixiu RoadChongchuan DistrictNantong226001China Department of Geriatrics The Second People’s Hospital of NantongAffiliated Rehabilitation Hospital of Nantong UniversityNo.298 Xinhua RoadChongchuan DistrictNantong226006China Institute of Orthopedics Tianjin Hospital Tianjin UniversityTianjin Key Laboratory of Orthopedic Biomechanics and Medical EngineeringNo.155 Munan RoadHeping DistrictTianjin300050China The First People’s Hospital of Yunnan Province No.157 Jinbi RoadXishan DistrictKunming650034China Academy of Medical Engineering and Translational Medicine Tianjin UniversityNo.92 Weijin RoadNankai DistrictTianjin300072China

Compared to conventional artificial nerve guide conduits (NGCs) prepared using natural polymers or synthetic polymers, acellular nerve grafts (ACNGs) derived from natural nerves with eliminated immune components have natural bionic advantages in composition and structure that polymer materials do not have. To further optimize the repair effect of ACNGs, in this study, we used a composite technology based on supercritical carbon dioxide (scCO_(2)) extraction to process the peripheral nerve of a large mammal, the Yorkshire pig, and obtained an innovative Acellular nerve xenografts (ANXs, namely, CD + scCO_(2) NG). After scCO_(2) extraction, the fat and DNA content in CD + scCO_(2) NG has been removed to the greatest extent, which can better supported cell adhesion and proliferation, inducing an extremely weak inflammatory response. Interestingly, the protein in the CD + scCO_(2) NG was primarily involved in signaling pathways related to axon guidance. Moreover, compared with the pure chemical decellularized nerve graft (CD NG), the DRG axons grew naturally on the CD + scCO_(2) NG membrane and extended long distances. In vivo studies further revealed that the regenerated nerve axons had basically crossed the CD + scCO_(2) NG 3 weeks after surgery. 12 weeks after surgery, CD + scCO_(2) NG was similar to autologous nerves in improving the quality of nerve regeneration, target muscle morphology and motor function recovery and was significantly better than hollow NGCs and CD NG. Therefore, we believe that the fully decellularized and fat-free porcine ACNGs may be the most promising “bridge” for repairing human nerve defects at this stage and for some time to come.

关键词： Peripheral nerve regeneration Acellular nerve xenograft Supercritical extraction Peripheral nerve injury Nerve defect

Trends in Incidence Rates,Mortality Rates,and Age-Period-Cohort Effects of Cervical Cancer—China,2003–2017

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China CDC weekly 2022年第48期4卷 1070-1076,I0001-I0010页

作者： Kexin sun Rongshou Zheng Lin Lei Siwei Zhang Hongmei Zeng Shaoming Wang Li Li Ru Chen Bingfeng Han Ji peng Wenqiang Wei Jie He National Central Cancer Registry National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing MunicipalityChina Shenzhen Center for Chronic Disease Control Guangzhou CityGuangdong ProvinceChina Department of Thoracic Surgery National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing MunicipalityChina.

Introduction:This study reported the trends and analyzed the age-period-cohort effects on the incidence and mortality rates of cervical cancer in ***:The age-standardized incidence rate(ASIR)and mortality rate(ASMR)by Segi’s world standard population were calculated using qualified consecutive data from 22 cancer registries from 2003 to 2017 in *** performed joinpoint analysis to describe the trends and age-period-cohort analysis to estimate the independent effects of age,period and cohort on trends in incidence and mortality rates of cervical ***:The ASIR and ASMR for cervical cancer in females over 20 years old increased during 2003−*** females50 years,the ASIR and ASMR increased both in urban and rural ***-period-cohort analysis showed increasing period effects on cervical cancer incidence and mortality during the whole *** cohort effects exhibited a downward-upwarddownward pattern for the incidence(1918–1938,1938–1963,1963–1993)and mortality rates(1918–1943,1943–1963,1963–1993)in urban areas,a fluctuating pattern for incidence rate and a continuing downward pattern for mortality rate(1918–1993)in rural ***:The increases in cervical cancer incidence and mortality rates can be mostly explained by period *** observed decreases in risk for cervical cancer incidence and mortality in young female generations,which were more obvious in urban areas.

关键词： mortality Cervical downward

基于个人潜力指数的结构化面试在临床医学研究生招生复试中的应用研究

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医学教育管理 2024年第2期10卷 179-185页

作者：熊艳程权威孙宇杰曾承叶少军胡晓燕叶啟发彭贵主武汉大学中南医院武汉大学肝胆疾病研究院武汉大学移植医学中心移植医学技术湖北省重点实验室武汉430071

在“双一流”背景下,研究生教育是引领“双一流”发展的关键因素,而研究生教育的发展和改革的首要措施是招生选拔制度改革。针对当前研究生复试存在的问题,为使临床医学研究生选拔更加科学、公平,为高校输送潜力大、高素质的临床医学人... 详细信息

在“双一流”背景下,研究生教育是引领“双一流”发展的关键因素,而研究生教育的发展和改革的首要措施是招生选拔制度改革。针对当前研究生复试存在的问题,为使临床医学研究生选拔更加科学、公平,为高校输送潜力大、高素质的临床医学人才,本文创新性地将美国教育考试服务中心为评价测试者“非认知技能和个人核心品质”而提出的“个人潜力指数”运用于“结构化面试”中,通过聚焦临床医学研究生招生复试面试环节,为研究生招生选拔改革提供了参考。

关键词：个人潜力指数结构化面试临床医学研究生招生

Coupling effect and characterization modeling of iron ore fines mixing and granulating at 0-1 mm

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Journal of Iron and Steel Research(International) 2019年第11期26卷 1154-1161页

作者： Dai-fei Liu Xian-ju Shi Chao-jun Tang Hai-peng Cao Jun Li School of Energy and Power Engineering Changsha University of Science and TechnologyChangsha 410114HunanChina Ironmaking Section Wuhan Branch of Baosteel Central Research Institute(R&D Center of Wuhan Iron&Steel Co.Ltd.)Wuhan 430000HubeiChina

Characteristic of iron ore is the essential factor of *** ores,namely specularite,magnetite concentrate and limonite,were selected as adhesion powder to investigate granulating behavior and evolution process of *** and modeling were performed to represent granulating behavior on the basis of selectivity,ballability and adhesion *** mass fraction of water and particles size of adhesion and nucleation were set at(11±1)%,0-1 mm and 3-5 mm,*** results show that selectivity and ballability promote the evolution of *** water absorption rate of specularite and the ballability of limonite are *** coupling effects exist in two ores mixing and present positive effect when the proportion of magnetite concentrate is greater than that of specularite or specularite and limonite *** three ores mixing,the coupling effect presents a complex superposition state.A characterization model of adhesion rate of mixing granulation was established by random forest *** output is adhesion rate,and its inputs include water absorption rate,balling index and mixing *** model parameters are 957 trees and four branches,and the training and prediction errors of the model are 2.3%and 3.7%,*** indicates that the random forest model can be used to represent coupling effects of mixing granulation.

关键词： Iron ore Granulating Coupling effect Modeling Random forest algorithm

峡谷区公路桥隧衔接段危岩运动模拟及轻量化防护预警体系探讨

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公路交通技术 2024年第3期40卷 98-109,117页

作者：孙耀明彭李廖志鹏黎鸣明袁兵杨斯亮许浒周小军招商局重庆交通科研设计院有限公司重庆400067 四川奥思特边坡防护工程有限公司成都610000 西南交通大学成都610000

深切峡谷区公路桥隧衔接段危岩落石极为普遍,具有高陡、面广量大、致灾随机性强等特点,存在识别难、绕避难、防治难、养护难等诸多工程难题,使得现有防护措施面临巨大挑战。以巫溪隧道出口危岩为例,采用无人机倾斜摄影测量技术建立山体... 详细信息

深切峡谷区公路桥隧衔接段危岩落石极为普遍,具有高陡、面广量大、致灾随机性强等特点,存在识别难、绕避难、防治难、养护难等诸多工程难题,使得现有防护措施面临巨大挑战。以巫溪隧道出口危岩为例,采用无人机倾斜摄影测量技术建立山体高精度三维模型,快速准确识别危岩及其分布,利用RockFall及CRSP-3D软件模拟落石运动特征。结果表明:1)落石以自由飞落、滚动、弹跳为主;2)无防护工况下落石最大弹跳高度大于70 m,最大冲击能量9000 kJ,主被动防护工况下,仍有10%的高位落石破网而出;3)LS-DYNA模拟显示,冲击作用下柔性棚洞可拦截破网落石,棚洞各构件处于弹性状态,但拱架基础在低能落石冲击下易破坏。基于此,提出深切峡谷区桥隧衔接段突发型及渐进型危岩落石全寿命周期轻量化预警防护体系,以实现“高能易修、中能无害、低能零损”的防护预警目标。

关键词：深切峡谷区危岩运动模拟柔性棚洞轻量化防护预警体系

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3种方法检测禽网状内皮组织增殖病毒人工感染鸡胚孵化雏鸡的带毒比较

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中国动物检疫 2024年第2期41卷 80-85页

作者：徐凤霞孙万里张亚文常爽王一新赵鹏山东农业大学动物科技学院山东泰安271018

为比较血液和粪便等样品采用不同方法检测禽网状内皮组织增殖病毒(REV)的准确率,从而为制定禽网状内皮组织增殖病(RE)净化程序提供参考,利用鸡胚卵黄囊接种构建REV垂直传播感染雏鸡模型,分别采用DF-1细胞病毒分离、RT-PCR检测和荧光定量... 详细信息

为比较血液和粪便等样品采用不同方法检测禽网状内皮组织增殖病毒(REV)的准确率,从而为制定禽网状内皮组织增殖病(RE)净化程序提供参考,利用鸡胚卵黄囊接种构建REV垂直传播感染雏鸡模型,分别采用DF-1细胞病毒分离、RT-PCR检测和荧光定量RT-PCR检测,对1日龄雏鸡血液和胎粪样品,7~70日龄鸡(每隔1周)的血液和泄殖腔棉拭子样品,进行REV检测和结果比较。结果显示:对1日龄出壳的SPF鸡血浆进行检测,荧光定量RT-PCR灵敏度最高,阳性检出率为100%(25/25),其次为病毒分离,阳性检出率为96%(24/25),RT-PCR检出率最低;对1日龄出壳的SPF鸡胎粪进行检测,荧光定量RT-PCR与病毒分离灵敏度一致,阳性检出率均为80%(20/25),RT-PCR检出率最低,为28%(7/25)。对7~70日龄鸡(每隔1周)进行血液和泄殖腔棉拭子检测,3种方法阳性检出率与1日龄检测情况总体相似,检出率从高到低依次为荧光定量RT-PCR、病毒分离和RT-PCR。结果表明,在同一检测时间点使用同一检测方法,胎粪/泄殖腔棉拭子REV阳性检出率基本低于血液检出率。本研究初步比较了不同方法检测REV人工感染鸡胚孵化雏鸡的带毒情况,为实施REV净化奠定了基础。

关键词：禽网状内皮组织增殖病毒病毒分离 RT-PCR 荧光定量RT-PCR

Rock Dynamic Crack Propagation Behaviour and Determination Method with Improved Single Cleavage Semi-circle Specimen Under Impact Loads

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Acta Mechanica Solida Sinica 2020年第6期33卷 793-811页

作者： fei Wang Meng Wang Zheming Zhu Jianhui Deng Mohaddeseh Mousavi Nezhad Hao Qiu peng Ying Failure Mechanics&Engineering Disaster Prevention and Mitigation Key Laboratory of Sichuan ProvinceSichuan UniversityChengdu 610065China Key Laboratory of Deep Underground Science and Engineering(Sichuan University) Ministry of EducationChengdu 610065China School of Engineering The University of WarwickCoventry CV47ALUK

This paper studied the rock dynamic fracture propagation under impact loads elaborately with a determination method proposed to calculate crack propagation dynamic stress intensity factor(DSIF).By utilizing the split-Hopkinson pressure bar,the impact experiments with an improved single cleavage semi-circle(ISCSC)specimen were conducted to illuminate the dynamic crack propagation ***,the fracture characteristics and crack propagation velocity were obtained by the crack propagation *** experiments with a numerical approach,the crack propagation dynamic stress intensity factors were calculated by an experimental—numerical method with fractal ***,a finite difference model was developed based on the tensile fracture softening damage *** the analysis of numerical and experimental results,the crack propagation behaviour and mechanism of crack arrest were discussed *** results demonstrate that the novel ISCSC specimen shows a definite advantage in determining crack propagation and arrest ***,the crack arrest DSIF is larger than the average propagation DSIF with a sharp ***,the numerical simulation results which agree well with the actual crack propagation illustrate that the crack arrest should be dominated by the compressive stress perpendicular to the crack path,and there were several arrest pauses existing in the transitory crack arrest process.

关键词： Impact loads Crack propagation Crack arrest Numerical simulation Fractal method Dynamic stress intensity factor