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橡胶水泥土动剪模量和阻尼比共振柱试验研究

振动与冲击 2024年第12期43卷 266-275页

作者：郭端伟何杰宋德新王忍李凤山湖南工业大学土木工程学院湖南株洲412007 交通运输部南海航海保障中心广州航标处广州510320 湖南省第二工程有限公司长沙410015

橡胶水泥土作为一种经济环保的耐腐蚀轻质填筑材料,在沿海港口工程及灯塔等基础建设中具有广泛的应用前景。基于共振柱试验,对不同橡胶掺量、水泥掺量和围压下橡胶水泥土动力特性展开研究,重点探究各影响因素对其动剪模量和阻尼比的影... 详细信息

橡胶水泥土作为一种经济环保的耐腐蚀轻质填筑材料,在沿海港口工程及灯塔等基础建设中具有广泛的应用前景。基于共振柱试验,对不同橡胶掺量、水泥掺量和围压下橡胶水泥土动力特性展开研究,重点探究各影响因素对其动剪模量和阻尼比的影响规律。结果表明:固结压力下橡胶水泥土的累计轴向应变随着橡胶掺量和围压的增大而增大,随水泥掺量增大而减小;橡胶水泥土动剪模量曲线衰减程度随橡胶掺量的增加和水泥掺量的减小而减弱,非线性特征减弱,而受围压影响则较小;最大动剪模量随着橡胶掺量的增大而减小,随水泥掺量和围压的增大而增大。当橡胶掺量较低或水泥掺量较高时,其掺量改变对最大动剪模量影响最大;橡胶的掺入减缓了动剪模量衰减幅度,并且在较低围压下促使其更早地发生衰减。而水泥掺量的减小和围压的增大则会推迟衰减,衰减幅度也相对更大;阻尼比随动剪应变的增加而单调递增,增大橡胶掺量和减小围压会使其阻尼比增大,当水泥掺量小于15%时,阻尼比随水泥掺量增加而增大,而当水泥掺量大于15%时,阻尼比反而随之降低。

关键词：橡胶水泥土动剪模量阻尼比配合比共振柱试验

腹腔镜肝血管瘤剥除术治疗成人肝脏卡-梅综合征1例

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中华肝胆外科杂志 2024年第3期30卷 218-219页

作者：周新博李昂李永刘建华王威张敬坡李凤山河北医科大学第一医院肝胆胰外科石家庄050000 河北医科大学第二医院肝胆外科石家庄050000

患者女性,38岁,因"上腹部胀痛4月余"于河北医科大学第一医院入院治疗。体格检查见肝肋下10.0 cm。术前实验室检查:血小板93×10^(9)/L、活化部分凝血活酶时间30.7 s、凝血酶原时间12.7 s、凝血酶时间18.6 s、纤维蛋白原1.22 g/L、D-二聚... 详细信息

患者女性,38岁,因"上腹部胀痛4月余"于河北医科大学第一医院入院治疗。体格检查见肝肋下10.0 cm。术前实验室检查:血小板93×10^(9)/L、活化部分凝血活酶时间30.7 s、凝血酶原时间12.7 s、凝血酶时间18.6 s、纤维蛋白原1.22 g/L、D-二聚体56.84 mg/L。上腹部CT增强扫描示:肝脏多发类圆形低密度影,考虑肝脏多发血管瘤。术前诊断为卡-梅综合征。行腹腔镜肝血管瘤剥除术治疗。术后病理证实为肝海绵状血管瘤。术后随访7个月,患者肝功能及凝血相关指标已恢复正常。

关键词：肝海绵状血管瘤凝血酶时间术前诊断凝血酶原时间低密度影活化部分凝血活酶时间纤维蛋白原术后病理

吲哚菁绿荧光显影导航联合改良胰胃吻合应用于腹腔镜保留十二指肠胰头切除术的临床疗效

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中华肝胆外科杂志 2024年第3期30卷 197-201页

作者：张敬坡刘建华李赋哲周新博李凤山河北医科大学第一医院肝胆胰外科石家庄050000 河北医科大学第二医院肝胆外科石家庄050000 河北医科大学第一医院重症医学科石家庄050000

目的探讨吲哚菁绿荧光显影导航联合改良胰胃吻合应用于腹腔镜保留十二指肠胰头切除术(LDPPHR)的可行性、安全性及疗效。方法回顾性分析河北医科大学第一医院肝胆胰外科2019年1月至2022年1月接受吲哚菁绿荧光显影导航联合改良胰胃吻合的L... 详细信息

目的探讨吲哚菁绿荧光显影导航联合改良胰胃吻合应用于腹腔镜保留十二指肠胰头切除术(LDPPHR)的可行性、安全性及疗效。方法回顾性分析河北医科大学第一医院肝胆胰外科2019年1月至2022年1月接受吲哚菁绿荧光显影导航联合改良胰胃吻合的LDPPHR治疗的14例患者临床资料,其中男性4例,女性10例,年龄(40.6±7.1)岁。记录患者手术时间、术中出血量、术后并发症及随访情况。结果14例患者均顺利完成手术,围手术期无吲哚菁绿过敏反应,术中吲哚菁绿染色显影胆总管效果良好。手术时间(325.71±23.00)min,其中胰胃吻合时间(18.32±1.52)min。术中出血200(150,300)ml,无术中输血。术后发生A级胰瘘3例、胆瘘1例、胆道狭窄1例。全部患者均获得随访,随访1~18个月,中位随访时间10个月。1例患者术后间断发热,于术后1月门诊复查磁共振胰胆管造影提示胆道狭窄,再次入院后经内镜下胆道支架置入治疗痊愈出院。结论吲哚菁绿荧光显影导航技术辅助LDPPHR安全、可行,联合改良胰胃吻合减少了空肠吻合步骤,有效提升了手术效能。

关键词：胰腺肿瘤腹腔镜检查保留十二指肠胰头切除术吲哚菁绿荧光显影技术胰胃吻合

Nest site characteristics and nest loss of Marsh Grassbird at Zhalong National Nature Reserve, China

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Journal of Forestry Research 2015年第3期26卷 785-790页

作者： Qiang Wang Xuehong Zhou fengshan li Yuming Zhang Feng li College of Wildlife Resource Northeast Forestry University Key Laboratory of Wetland Ecology and Environment CAS International Crane Foundation E-11376 Shady Lane RoadBaraboo WI 53913 USA

The Marsh Grassbird Locustella pryeri is an uncommon songbird endemic to East Asia. Suitable nest- site selection can minimize nest loss, especially for open- cup and ground nesting passerines. We located and mon- itored 66 Marsh Grassbird nests during 2004-2006 in Zhalong National Nature Reserve, northeast China, to identify characteristics of preferred nest sites. Marsh Grassbird nested mainly at sites with dense vegetation cover, high undergrowth and dry standing reed stalks, as well as small shallow ponds or rivers. Nests were more successful when they were placed higher above ground in patches with greater litter thickness. Predation and flooding were the leading causes of nest failure, accounting for at least 33 and 25 % of 24 nests lost, respectively. We ad- vocate retention of some unharvested reed patches and implementation of irrigation strategies that avoid increas- ing water levels during the breeding period （May-July） of Marsh Grassbirds.

关键词： Flooding Japanese Marsh Warbler.Locustella pryeri Nest site Predation Zhalong

A revised species population estimate for the Bar-headed Goose(Anser indicus)

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Chinese Birds 2017年第1期8卷 57-62页

作者： Dongping liu Guogang Zhang fengshan li Tian Ma Jun Lu Fawen Qian KeyLaboratoryofForestProtectionofStateForestryAdministration ResearchInstituteofForestEcologyandEnvironmentProtectionChineseAcademyofForestry InternationalCraneFoundation

Background: The Bar-headed Goose(Anser indicus) is a species that relies heavily on the plateau wetlands of Asia and whose population was thought to be declining. Over the past decade, south-central Tibet, one of the most important wintering grounds, supported large numbers of Bar-headed Geese, but the population had not been regularly monitored in this ***: We surveyed wintering Bar-headed Geese along the Yarlung Zangbo, Lhasa and Nyang Qu rivers, the three major river valleys and their tributaries in south-central Tibet in January 2014 and recorded their location, flock size and habitat utilization. Based on these data and the latest wintering counts elsewhere, we revised the population estimate for this ***: We recorded more than 67,000 Bar-headed Geese in south-central Tibet during January 2014. By geographic area, the geese were most abundant in the Lhasa River valley(38.5%) and the Nyang Qu River valley(31.0%), and by administrative division in Lhunzhub(27.2%) and Shigatse(26.7%). Bar-headed Geese were most often observed feeding in winter wheat fields and ploughed fields, resting on pastureland and marshes. The approximate number of 67,000 geese recorded in Tibet is more than four times the estimate of 1993 for the same region and exceeds the most recent world population estimate of 52,000–60,000. Based on our work in Tibet and the latest wintering counts available from other areas, we revised the estimated population size of this species to 97,000–118,***: Our result reveals a remarkable increase in the number of Bar-headed Geese wintering in south-central Tibet. This population increase most likely stems from a proliferation of cropland and especially winter wheat fields in south-central Tibet. This habitat improvement may also cause short-stopping of the Bar-headed Goose and thus reduce mortality of the geese that would otherwise undertake a somewhat daunting trans-Himalayan migration.

关键词： Bar-headed Goose Species population estimate Tibet Wintering ground

芦笋根际与非根际土壤微生物群落结构及多样性特征

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四川农业大学学报 2024年第2期42卷 330-338页

作者：盛玉珍黄玲叶鹏盛赖佳刘勇张骞方刘佳李丰山韦树谷四川省农业科学院经济作物研究所/蔬菜种质与品种创新四川省重点实验室成都610300 彭州市乡村投资发展有限公司四川彭州611934

【目的】探明四川芦笋根际和非根际土壤微生物群落多样性特征,为芦笋土壤生态系统的构建和保持提供理论依据。【方法】以芦笋根际和非根际土壤为研究对象,测定其土壤理化指标,同时利用高通量测序技术分析土壤细菌、真菌群落特征。【结... 详细信息

【目的】探明四川芦笋根际和非根际土壤微生物群落多样性特征,为芦笋土壤生态系统的构建和保持提供理论依据。【方法】以芦笋根际和非根际土壤为研究对象,测定其土壤理化指标,同时利用高通量测序技术分析土壤细菌、真菌群落特征。【结果】芦笋根际土壤pH、全钾、速效钾均低于非根际土壤,而有机质、全氮、水解氮、全磷和有效磷均高于非根际。根际土壤细菌的多样性和丰度高于非根际,根际真菌的丰度高于非根际,而根际真菌的多样性低于非根际。芦笋根际和非根际土壤优势细菌门主要是变形菌门、厚壁菌门、酸杆菌门、放线菌门、绿弯菌门,优势真菌门为担子菌门、子囊菌门。LSfSe分析发现在根际土壤中共鉴定14个细菌类群和20个真菌类群与非根际土壤有显著差异。主成分分析(PCA)表明,根际与非根际在土壤细菌及真菌群落结构多样性上均存在较大差异。冗余分析(RDA)显示,pH是影响土壤微生物群落结构组成最重要的因素。【结论】扩展了芦笋根际微生物的多样性的认知谱系,为探讨通过调控土壤微生物群落结构实现芦笋优质高产栽培提供理论依据。

关键词：芦笋根际土壤微生物多样性

Effects of Sinusoidal Vibration of Crystallization Roller on Composite Microstructure of Ti/Al Laminated Composites by Twin-Roll Casting

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 196-205页

作者：李励杜凤山 National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004China College of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China

A new,innovative vibration cast-rolling technology of “electromagnetic stirring+dendrite breaking+asynchronous rolling” was proposed with the adoption of sinusoidal vibration of crystallization roller to prepare Ti/Al laminated composites,and the effect of sinusoidal vibration of crystallization roller on composite microstructure was investigated in *** results show that the metallurgical bonding of titanium and aluminum is realized by mesh interweaving and mosaic meshing,instead of transition bonding by forming metal compound *** meshing depth between titanium and aluminum layers (6.6μm) of cast-rolling materials with strong vibration of crystallization roller (amplitude 0.87 mm,vibration frequency 25 Hz) is doubled compared with that of traditional cast-rolling materials (3.1μm),and the composite interfacial strength(27.0 N/mm) is twice as high as that of traditional cast-rolling materials (14.9 N/mm).This is because with the action of high-speed superposition of strong tension along the rolling direction,strong pressure along the width direction and rolling force,the composite linearity evolves from "straight line" with traditional casting-rolling to "curved line",and the depth and number of cracks in the interface increases greatly compared with those with traditional cast-rolling,which leads to the deep expansion of the meshing area between interfacial layers and promotes the stable enhancement of composite quality.

关键词： laminated composites sinusoidal vibration composite microstructure

Automatic recognition of landslides based on YOLOv7 and attention mechanism

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Journal of Mountain Science 2024年第8期21卷 2681-2695页

作者： SONG Yewei GUO Jie WU Gaofeng MA fengshan li Fangrui Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Sciences Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Landslide disasters comprise the majority of geological incidents on slopes,posing severe threats to the safety of human lives and property while exerting a significant impact on the geological *** rapid identification of landslides is important for disaster prevention and control;however,currently,landslide identification relies mainly on the manual interpretation of remote sensing *** interpretation and feature recognition methods are time-consuming,labor-intensive,and challenging when confronted with complex ***,automatic landslide recognition has emerged as a pivotal avenue for future *** this study,a dataset comprising 2000 landslide images was constructed using open-source remote sensing images and *** YOLOv7 model was enhanced using data augmentation algorithms and attention *** optimization models were formulated to realize automatic landslide *** findings demonstrate the commendable performance of the optimized model in automatic landslide recognition,achieving a peak accuracy of 95.92%.Subsequently,the optimized model was applied to regional landslide identification,co-seismic landslide identification,and landslide recognition at various scales,all of which showed robust recognition ***,the model exhibits limitations in detecting small targets,indicating areas for refining the deep-learning *** results of this research offer valuable technical support for the swift identification,prevention,and mitigation of landslide disasters.

关键词： Deep learning Landslide detection Natural disasters Attention mechanism Remote sensing

Comparison of debris flow susceptibility assessment methods:support vector machine,particle swarm optimization,and feature selection techniques

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Journal of Mountain Science 2024年第2期21卷 397-412页

作者： ZHAO Haijun WEI Aihua MA fengshan DAI Fenggang JIANG Yongbing li Hui Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China Hebei Province Key Laboratory of Sustained Utilization&Development of Water Recourse Hebei GEO UniversityShijiazhuang 050031China School of Water Resources and Environment Hebei GEO UniversityShijiazhuang 050031China The Sixth Geological Brigade of Geological Mineral Exploration and Development Bureau of Hebei Province Shijiazhuang 050085China

The selection of important factors in machine learning-based susceptibility assessments is crucial to obtain reliable susceptibility *** this study,metaheuristic optimization and feature selection techniques were applied to identify the most important input parameters for mapping debris flow susceptibility in the southern mountain area of Chengde City in Hebei Province,China,by using machine learning *** total,133 historical debris flow records and 16 related factors were *** support vector machine(SVM)was first used as the base classifier,and then a hybrid model was introduced by a two-step ***,the particle swarm optimization(PSO)algorithm was employed to select the SVM model ***,two feature selection algorithms,namely principal component analysis(PCA)and PSO,were integrated into the PSO-based SVM model,which generated the PCA-PSO-SVM and FS-PSO-SVM models,*** statistical metrics(accuracy,recall,and specificity)and the area under the receiver operating characteristic curve(AUC)were employed to evaluate and validate the performance of the *** results indicated that the feature selection-based models exhibited the best performance,followed by the PSO-based SVM and SVM ***,the performance of the FS-PSO-SVM model was better than that of the PCA-PSO-SVM model,showing the highest AUC,accuracy,recall,and specificity values in both the training and testing *** was found that the selection of optimal features is crucial to improving the reliability of debris flow susceptibility assessment ***,the PSO algorithm was found to be not only an effective tool for hyperparameter optimization,but also a useful feature selection algorithm to improve prediction accuracies of debris flow susceptibility by using machine learning *** high and very high debris flow susceptibility zone appropriately covers 38.01%of the study area,where debris flow may occur under intens

关键词： Chengde Feature selection Support vector machine Particle swarm optimization Principal component analysis Debris flow susceptibility