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Unstable evolution of railway slope under the rainfall-vibration joint action

Journal of Mountain Science 2024年第4期21卷 1419-1431页

作者： DONG Haoyu WANG Jiading ZHANG Dengfei LI Lin xu yuanjun State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China

Understanding the unstable evolution of railway slopes is the premise for preventing slope failure and ensuring the safe operation of ***,as two major factors affecting the stability of railway slopes,few scholars have explored the unstable evolution of railway slopes under the joint action of *** on the model test of sandy soil slope,the unstable evolution process of slope under locomotive vibration,rainfall,and rainfall-vibration joint action conditions was simulated in this *** comparing and analyzing the variation trends of soil pressure and water content of slope under these conditions,the change laws of pore pressure under the influence of vibration and rainfall were *** main control factors affecting the stability of slope structure under the joint action conditions were further *** with the slope failure phenomena under these three conditions,the causes of slope instability resulting from each leading factor were ***,according to the above conclusions,the unstable evolution of the slope under the rainfall-vibration joint action was *** test results show that the unstable evolution process of sandy soil slope,under the rainfall-vibration joint action,can be divided into:rainfall erosion cracking,vibration promotion penetrating,and slope instability sliding three *** the process of slope unstable evolution,rainfall and vibration play the roles of inducing and promoting slide *** addition,the deep cracks,which are the premise for the formation of the sliding surface,and the violent irregular fluctuation of soil pressure,which reflects the near penetration of the sliding surface,constitute the instability characteristics of the railway slope *** paper reveals the unstable evolution of sandy soil slopes under the joint action of rainfall-vibration,hoping to provide the theoretical basis for the early warning and prevention technology of railway slopes.

关键词： Rainfall vibration joint action Small scale model tests Unstable evolution process Unstable characteristics Inducing sliding and promoting sliding

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Vibration-induced acceleration of infiltration in loess

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Science China Earth Sciences 2021年第4期64卷 611-630页

作者： Jiading WANG yuanjun xu Dengfei ZHANG Tianfeng GU State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China

Coupled effects of railway vibration, rainfall, and drying-wetting cycles contribute to new types of loess disasters such as the collapse and vibration-induced settlement of the railway subgrade, loess mass disintegration, and slope sliding,during the large-scale construction and operation of high-speed or heavy-haul railways in China. This has significant consequences for railways that require millimetre-level deformation control, seriously threatening railway operation and people's lives. Therefore, for the first time, "five vibration-induced effects" on loess subjected to vibration, water immersion, and drywetting cycles are discussed including the vibration-induced acceleration of cracking, infiltration, disintegration, sliding, and subsidence. In this paper, the vibration-induced acceleration of infiltration is discussed mainly. The response of loess to locomotive vibration along railways was determined using field sampling and data processing. The dominant frequency of locomotive vibration are 18-22 Hz and the maximum amplitude is 0.4 mm. Tests regarding the vibration-induced acceleration of the permeability were conducted on intact loess using a newly developed vibration permeability apparatus. The results reveal that the vibration accelerates the water permeability and increases the water saturation of loess. The permeability coefficient of saturated loess under vibration is ~1.5-20 times of that without vibration, reaching a maximum at a vibration frequency of 20 ***-induced infiltration tests were carried out on a loess column and the vibration-induced acceleration of water infiltration, wetting front evolution, and air outflow were analysed. The vibration-induced acceleration of infiltration strongly depends on the dry density, vibration frequency, and vibration amplitude. This pioneering work explores the mechnism of loess disasters triggered by locomotive vibration, rainfall, and drying-wetting cycles.

关键词： Loess disaster Locomotive vibration Five vibration-induced effects Vibration-induced acceleration of infiltration Air escape Loess landslide

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我国农业机械电动化发展探析

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南方农机 2024年第7期55卷 26-30页

作者：陈立创徐源俊李贝柳州职业技术学院广西柳州545007

【目的】促进绿色智能农业机械和节本增效农业机械化技术推广应用,推进电动农机、智慧农机、智能农机应用,实现节能减排。【方法】文章梳理分析了我国电动农业机械产业与纯电动、增程式、混合动力及氢燃料电池技术的发展现状,发现农业... 详细信息

【目的】促进绿色智能农业机械和节本增效农业机械化技术推广应用,推进电动农机、智慧农机、智能农机应用,实现节能减排。【方法】文章梳理分析了我国电动农业机械产业与纯电动、增程式、混合动力及氢燃料电池技术的发展现状,发现农业机械电动化存在产业发展相对滞后、实际运用成本高、续航里程受限及技术研发力量薄弱等问题,并探索了发展农业机械电动化技术的路线。【结果】发展电动农业机械应当借鉴具有优势地位的电动汽车、电动工程机械发展路径,借助先进的电动汽车,电动工程机械产业链、供应链和技术服务平台,结合农业机械规格类型及应用环境、工作条件、负载状况等,科学合理发展纯电动、混合动力、增程式或氢燃料电池电动农业机械。【结论】本研究有助于加快推进农业机械化,提升农机机械化率,加强电动化、智能化、复合型农业机械装备研发应用,推动农业机械产业面向先进技术装备转型升级。

关键词：电动化电动农机新能源农业机械

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Recent development of chemical components in propolis

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Frontiers in Biology 2009年第4期4卷 385-391页

作者： yuanjun xu Liping LUO Bin CHEN Yuxin FU Life Science and Food Engineering College Nanchang UniversityNanchang 330047China

Propolis is a resinous substance collected by honeybees from various plant *** account of its chemical composition,propolis possesses several biologi-cal and pharmacological *** recent years,many papers have provided information concerning its *** review compiles data from most studies of propolis,focusing on the chemical composition of ethanol extracts of propolis(EEP),water extracts of propolis(WEP),and volatile oils from propolis(VOP).The characteristic compounds of EEP are polyphenols includ-ing flavonoids and related phenolic acids,and flavonoids are the most abundant and effective *** are considered to contribute more to the antibacterial,antiviral,and antioxidant effects than the other *** main flavonoids in EEP are pinocembrin,galangin,chrysin,quercetin,kaempferol,and *** constituents reported to be in WEP include phenolic acids,caffeoylquinic acid,3-mono-O-caffeoylquinic acid,caffeic acid,flavonoids,*** propolis volatile compounds are benzyl alcohol,benzyl acetate,cinnamic alcohol,vanillin,eudensmol,cyclohexyl benzoate,and benzyl benzoate,which are responsible for several biological *** a natural mixture,propolis is widely used in medicine and cosmetics,as well as being a constituent of health *** propolis has been used extensively,information on its composition is not only of interest to the academic field,but also to propolis users.

关键词： propolis chemical composition ethanol extract water extract volatile oil

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Preliminary Study on the Effects of Different Nutrient Solutions on the Parasitism of Cuscuta grandis to Mikania micrantha

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Agricultural Biotechnology 2021年第4期10卷 25-28,31页

作者： Haifan WANG Ruijie ZHANG yuanjun xu Jie GUO Yunnan Forestry Technological College Kunming 650224China Yunnan Forestry Senior Technical School Kunming 650000China

[Objectives]This study was conducted to investigate the effects of different nutrient solutions on the parasitism of Cuscuta grandis to Mikania micrantha.[Methods]The growth-promoting effect of *** parasitizing *** was studied through the use of different concentrations of plant growth regulators(naphthalene acetic acid,gibberellic acid)and compounds containing trace elements(manganese sulfate,copper sulfate,zinc nitrate,boric acid).[Results]Mixing naphthalene acetic acid with a concentration of 0.01 ml/L and gibberellic acid with a concentration of 1 mg/L at a ratio of 1∶3 and then adding an equal volume of compounds containing trace elements including manganese sulfate with a concentration of 0.1 mg/L,copper sulfate with a concentration of 0.1 mg/L,zinc nitrate with a concentration of 0.1 mg/L and boric acid with a concentration of 2 mg/L,the average stem length of the breeding group increased significantly,about 2.47 cm,showing a significant difference from the *** survival rate of the experimental group using the plant growth regulators and the trace elements was 66.67%,and the survival rate of the control group was 56.67%.[Conclusions]This study can fill the gap in the study of seed morphology of ***,and is also of great significance for the identification and quarantine of ***.

关键词： Breeding group Plant growth regulator Trace elements Survival rate

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Reducing children’s exposure to di(2-ethylhexyl)phthalate in homes and kindergartens in China:Impact on lifetime cancer risks and burden of disease

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Building Simulation 2024年第3期17卷 431-440页

作者： Dongsheng Tao Wen Sun Donghui Mo Yonghui Lin Wei Lv Daniel Mmereki Yousheng xu Yanghui Ye yuanjun Tang Chao Ye Cong Dong Zhongming Bu Zhejiang Ecowell Energy Management Technology Co. LtdHangzhouChina Department of Energy and Environmental System Engineering Zhejiang University of Science and TechnologyHangzhouChina Faculty of Health Sciences School of Clinical MedicineUniversity of the WitwatersrandParktown2193JohannesburgSouth Africa

Exposure to di(2-ethylhexyl)phthalate(DEHP)in the indoor environment has been linked with significant health risks for Chinese ***-phase DEHP concentrations in Chinese residences and kindergartens were estimated using a mass balance model based on the current baseline condition and control strategies(i.e.,increasing ventilation rate,reducing area of sources,using mechanical ventilation systems,and using portable air cleaners).The health benefits of each control strategy were quantified as the reduction in lifetime cancer risks(LCR)and burden of disease(BoD).In the current situation,the mean LCR and disability-adjusted life years(DALY)number attributable to indoor DEHP exposure for Chinese children were around 6.0×10^(−6) and 155 thousand,*** mean LCR and DALY might be reduced by 25%-54%and 16%-40%,respectively,by increasing air exchange rates by 100%,reducing the use of source materials by two-thirds or deploying commercial air cleaners in naturally ventilated ***,avoidable DALYs could result in a reduction of mean economic losses of 2.2-5.3 billion *** ventilation systems with filtration units may not be helpful for reducing children’s health ***-specific and tailor-made control measures are critical in lowering indoor exposure to DEHP to promote sustainable buildings and children’s health in China.

关键词： indoor air di(2-ethylhexyl)phthalate children exposure control strategies health benefits

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对高职院校教育科研论文期刊评价的思考

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科技管理研究 2008年第11期28卷 128-130页

作者：徐元俊娄底职业技术学院湖南娄底417000

对学术期刊的认定与评价,是搞科研工作的指南。国内期刊评价体系有多种,认定与评价高职学院教师的教育科研论文,应从中文核心期刊要目总览、中国社会科学引文索引、中国期刊方阵、中国人文社会科学核心期刊等四大要览中,评定出权威期刊... 详细信息

对学术期刊的认定与评价,是搞科研工作的指南。国内期刊评价体系有多种,认定与评价高职学院教师的教育科研论文,应从中文核心期刊要目总览、中国社会科学引文索引、中国期刊方阵、中国人文社会科学核心期刊等四大要览中,评定出权威期刊、重要期刊及其它等级的期刊,引导教师克服功利主义、急功近利思想,提高科研论文的质量,使科研成果从粗放型增长向集约型增长转变。

关键词：高职学院科研论文期刊评价分类思考

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提高科研能力增强高职学院的核心竞争力

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科技管理研究 2009年第2期29卷 117-118页

作者：徐元俊娄底职业技术学院湖南娄底417000

核心竞争力理论是当代战略管理学最前沿的主流学派,受核心竞争力理论的启发,高职学院应从加强科学研究、培养双师教师、提高科研能力等方面入手,来培育和提升高职院校的核心竞争力。

关键词：高职院校科研能力核心竞争力重要措施

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对高职院校科研激励机制的研究

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科技管理研究 2006年第1期26卷 152-154页

作者：徐元俊娄底职业技术学院湖南娄底417000

通过问卷调查,发现目前高职院校教师搞科研的动力,大多来自于职称、职务的升迁,这主要是因为科研管理中缺乏长效的激励机制。将激励理论应用于科研管理中,通过加强制度建设实现科学引导,从科研经费、成果奖励、人才选拔聘任、岗位考核... 详细信息

通过问卷调查,发现目前高职院校教师搞科研的动力,大多来自于职称、职务的升迁,这主要是因为科研管理中缺乏长效的激励机制。将激励理论应用于科研管理中,通过加强制度建设实现科学引导,从科研经费、成果奖励、人才选拔聘任、岗位考核、科研津贴、精神鼓励等方面构建激励机制,实现以人为本的管理模式。

关键词：高职院校科研工作以人为本激励机制

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基于水平集和支持向量机的图像声呐目标识别

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仪器仪表学报 2012年第1期33卷 49-55页

作者：许文海续元君董丽丽李瑛大连海事大学信息科学技术学院大连116026

为了能实现水下遇险目标的精确定位,首先要对声呐所获取的图像进行目标识别。利用水平集法获得水下声呐图像中目标轮廓后,提取目标轮廓的7个不变矩作为特征矢量,并将获取的不变矩特征输入到已经训练好的支持向量机中进行识别,从而得到... 详细信息

为了能实现水下遇险目标的精确定位,首先要对声呐所获取的图像进行目标识别。利用水平集法获得水下声呐图像中目标轮廓后,提取目标轮廓的7个不变矩作为特征矢量,并将获取的不变矩特征输入到已经训练好的支持向量机中进行识别,从而得到识别结果。所使用的识别方法综合了基于水平集提取轮廓的长处,不变矩的位移、尺度、旋转不变性的特点和支持向量机在小样本、非线性模式识别中的独特优势。实验结果表明:该方法对高分辨率图像声呐具有较高的识别率和较低的误判率,对原始声呐图像的目标识别率高达99%,对加入方差为0.09的高斯噪声的声呐图像的目标识别率可以达到97%。

关键词：声呐目标识别水平集不变矩支持向量机

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