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驼峰式长距离输水管线单向调压塔水锤防护研究

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水电能源科学 2024年第9期42卷 157-161页

作者：陈明辉周建旭河海大学水利水电学院江苏南京210098

驼峰式管线作为长输水系统的典型布置方式,中间凸起管段的局部水锤特性及其水锤防护问题复杂。通过驼峰式管线高点下游侧管线坡度与水力坡度的比较分析,阐明了单向调压塔对驼峰式长距离输水管线的防护机理,并推导了单向调压塔设置高度... 详细信息

驼峰式管线作为长输水系统的典型布置方式,中间凸起管段的局部水锤特性及其水锤防护问题复杂。通过驼峰式管线高点下游侧管线坡度与水力坡度的比较分析,阐明了单向调压塔对驼峰式长距离输水管线的防护机理,并推导了单向调压塔设置高度的近似解析公式。进一步基于有压输水管道特征线法,融合单向调压塔和调流阀等水力边界,建立了相应的输水系统水锤分析模型,开展了系统的水锤防护及其优化研究。分析表明,基于建立的单向调压塔设置分析方法,在驼峰式管线合理设置单向调压塔,能够有效实现系统的水锤防护,并可考虑管线布置特性进一步优化,数值计算和理论分析一致;单向调压塔直径和阻抗孔直径是评估单向调压塔水锤防护效果的重要参数,均存在一最优数值解,继续增大单向调压塔直径或阻抗孔直径对改善水锤防护效果作用很小。

关键词：驼峰式长输水管线特征线法水锤防护单向调压塔

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裂隙水作用下岩质边坡平面滑动力学模型

公路交通科技 2024年第2期41卷 88-95,104页

作者：姜楠张安然张芳陈明晖曹晓伟黄河水利职业技术学院河南开封475004 河南省跨流域区域引调水运行与生态安全工程研究中心河南开封475004 中国建筑第八工程局有限公司华北分公司天津300450 昊鼎地基基础工程有限公司河南郑州450008

在降雨等水力条件作用下沿岩层层面的平面滑动是顺层岩质边坡最常见的一种破坏模式,而目前关于该类边坡的稳定性计算方法几乎很少考虑裂隙面粗糙度对地下水渗流力及滑面抗剪强度的影响,进而导致其稳定性计算结果误差较大。为此,首先对... 详细信息

在降雨等水力条件作用下沿岩层层面的平面滑动是顺层岩质边坡最常见的一种破坏模式,而目前关于该类边坡的稳定性计算方法几乎很少考虑裂隙面粗糙度对地下水渗流力及滑面抗剪强度的影响,进而导致其稳定性计算结果误差较大。为此,首先对地下水作用下的顺层岩质边坡受力特征进行分析,认为地下水将对滑动岩体产生3个方面的力学作用:张裂隙中的静水压力、滑面上的扬压力和渗流力,由此建立了相应的边坡稳定性计算模型。其次,通过引入裂隙面粗糙度对裂隙抗剪强度及地下水渗流力的影响,提出了考虑裂隙粗糙及地下水渗流力的顺层岩质边坡稳定性计算模型。而后,通过对含一条贯通粗糙裂隙的岩质边坡稳定性为例,验证了该模型计算结果的合理性,同时计算结果表明裂隙面粗糙度系数JRC对边坡稳定性有重要影响,必须予以考虑。最后,基于参数敏感性分析研究了主要参数如裂隙面粗糙度系数、裂隙基本摩擦角、裂隙宽度、裂隙壁面岩石抗压强度及地下水位高度等对边坡稳定性的影响,结果表明:仅裂隙宽度对边坡稳定性影响很小,而其他参数对边坡稳定性影响则相对较大,不容忽视。且裂隙面粗糙度对边坡稳定性的影响与裂隙壁面岩石抗压强度密切相关,随着其增加,裂隙面粗糙度对边坡稳定性的影响程度逐渐变大。

关键词：道路工程岩质边坡平面滑动力学模型裂隙水粗糙裂隙裂隙抗剪强度准则

基于粒径分布的机动车尾气颗粒物排放检测方法

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内燃机与配件 2024年第6期 97-99页

作者：吴善岳陈春飞陈明惠董荣对玉环通达机动车辆综合性能检测站台州317605 乐清市宁康西路机动车检测有限公司温州325600 杭州宜捷机动车检测有限公司杭州311103 苍南县圆通机动车检测有限公司温州325800

常规的机动车尾气颗粒物排放检测方法使用NDIR红外气体传感器采集颗粒物排放信息,易受动态变化尾气浓度影响,导致检测的尾气颗粒物排放浓度与实际排放浓度偏差较高,因此需要基于粒径分布设计一种全新的机动车尾气颗粒物排放检测方法。... 详细信息

常规的机动车尾气颗粒物排放检测方法使用NDIR红外气体传感器采集颗粒物排放信息,易受动态变化尾气浓度影响,导致检测的尾气颗粒物排放浓度与实际排放浓度偏差较高,因此需要基于粒径分布设计一种全新的机动车尾气颗粒物排放检测方法。即计算各微粒的质量浓度,基于粒径分布提取了尾气颗粒物排放特征,再根据经典PID控制算法,构建了Lug Down尾气颗粒物排放检测模型,从而完成了尾气颗粒物排放检测。实验结果表明,设计的尾气颗粒物排放粒径分布检测方法检测的尾气颗粒物排放浓度与实际排放浓度较拟合,证明设计的检测方法的检测效果较好,有一定的应用价值,为提高大气空气质量作出了一定的贡献。

关键词：粒径分布机动车尾气颗粒物排放检测

An EMS mutant library for cucumber

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Journal of Integrative Agriculture 2018年第7期17卷 1612-1619页

作者： chen chen CUI Qing-zhi HUANG San-wen WANG Shen-hao LIU Xiao-hong LU Xiang-yang chen hui-ming TIAN Yun College of Bioscience and Biotechnology Hunan Agricultural UniversityChangsha 410128P.R.China Hunan Vegetable Research Institute Hunan Academy of Agricultural SciencesChangsha 410125P.R.China Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture/Sino-Dutch Joint Laboratory of Horticultural Genomics Institute of Vegetables and FlowersChinese Academy of Agricultural SciencesBeijing 100081P.R.China Key Laboratory for Agricultural Biochemistry and Biotransformation of Hunan Provincial University Changsha 410128P.R.China Hunan Co-Innovation Center for Utilization of Botanical Functional Ingredients Changsha 410128P.R.China

Cucumber is an important vegetable crop and a model crop for the study of sex expression in plants. However, the genomic resources and tools for functional genomics studies in cucumber are still limited. In this paper, we conducted ethyl methyl sulfone（EMS） mutagenesis in the northern China ecotype cucumber inbred line 406 to construct a mutant library. We optimized the conditions of EMS mutagenesis on inbred line 406 which included treatment of seeds at 1.5% EMS for 12h. We obtained a number of mutant lines showing inheritable morphological changes in plant architecture, leaves, floral organs, fruits and other traits through M1, M2 and M3 generations. The F2 segregating populations were constructed and *** found that a short fruit mutant and a yellow-green fruit peel mutant were both under the control of a single recessive gene, respectively. These results provide valuable germplasm resources for the improvement of cucumber genetics and functional genomic research.

关键词： cucumber EMS mutant library traits

利福平联合复方新诺明对复治涂片阳性肺结核炎性因子的影响

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中国药物应用与监测 2024年第1期21卷 17-20页

作者：陈巧玲陈炘叶姿罗卿夏旭辉刘发彬王超秀刘鑫陈明惠内江市第一人民医院感染肝病科内江641000

目的分析利福平联合复方新诺明辅助治疗对复治涂片阳性肺结核患者疗效和血清炎性因子水平的影响。方法将2017年5月—2022年8月我院收治80例复治涂片阳性肺结核患者使用随机信封法分为观察组及对照组各40例。对照组采用利福平治疗,观察... 详细信息

目的分析利福平联合复方新诺明辅助治疗对复治涂片阳性肺结核患者疗效和血清炎性因子水平的影响。方法将2017年5月—2022年8月我院收治80例复治涂片阳性肺结核患者使用随机信封法分为观察组及对照组各40例。对照组采用利福平治疗,观察组采用利福平联合复方新诺明辅助治疗;治疗后对患者临床疗效、复发率及痰菌阴转率进行评估,并检测治疗前后血清炎性因子水平。结果治疗后观察组病灶吸收率90.00%高于对照组77.50%,空洞缩小率95.00%高于对照组82.50%,差异均具有统计学意义(均P<0.05);观察组复发率2.50%低于对照组15.00%,痰菌阴转率97.50%高于对照组80.00%,差异均具有统计学意义(均P<0.05);观察组治愈率95.00%高于对照组85.00%,差异具有统计学意义(P<0.05)。治疗后观察组血中白细胞介素-37(IL-37)、触珠蛋白(HP)、骨桥蛋白(OPN)水平均下降,观察组3种因子水平分别为(4.63±0.83)pg·mL^(-1)、(810.38±31.64)μg·mL^(-1)、(189.19±20.74)pg·mL^(-1)低于对照组的(6.33±0.91)pg·mL^(-1)、(1283.73±101.67)μg·mL^(-1)、(456.28±45.92)pg·mL^(-1),差异均具有统计学意义(均P<0.05)。结论利福平联合复方新诺明对复治涂片阳性肺结核患者后有助于提高临床疗效,改善血液中IL-37、HP、OPN水平。

关键词：利福平复方新诺明复治涂片阳性肺结核触珠蛋白白细胞介素-37 骨桥蛋白

2020—2022年天津市南开医院临床常见胆道感染的病原学特征及危险因素分析

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中国中西医结合外科杂志 2024年第2期30卷 248-253页

作者：陈明慧张爱民薛海玲房杰贾晓冬天津市南开医院医学检验科天津300100 天津金域医学检验实验室有限公司天津300100

目的:分析天津市南开医院临床常见的胆道感染病原学特征及危险因素,为胆道感染的临床治疗用药提供依据。方法:选取2020年1月—2022年12月天津市南开医院收治的672例胆道疾病患者作为研究对象,根据是否发生胆道感染(BTI)将患者分为BTI组(... 详细信息

目的:分析天津市南开医院临床常见的胆道感染病原学特征及危险因素,为胆道感染的临床治疗用药提供依据。方法:选取2020年1月—2022年12月天津市南开医院收治的672例胆道疾病患者作为研究对象,根据是否发生胆道感染(BTI)将患者分为BTI组(n=361)和非BTI组(n=311);采集患者的年龄、性别、基础疾病情况、胆结石数量、抗菌药物使用情况和病原学检查结果等资料,分析胆石症患者并发BTI的危险因素与病原学特征。结果:胆汁培养共分离病原菌3534株,其中革兰阴性菌2375株,占67.20%;革兰阳性菌1058株,占29.94%;真菌92株,占2.60%。大肠埃希菌对环丙沙星的耐药率呈上升趋势(P65岁、有胆道手术史、结石数目>2个是胆石症患者并发BTI的独立危险因素(P<0.05)。结论:临床胆道感染分离的病原菌以革兰阴性杆菌最常见,耐药性不断变迁,应根据药敏结果合理用药;患者发生胆道感染与年龄、胆道手术史和胆结石数目有相关性,临床应增强感染防护。

关键词：胆道感染病原菌耐药性

Establishment of a Stable PrP^(Sc) Panel from Brain Tissues of Experimental Hamsters with Scrapie Strain 263K

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Biomedical and Environmental Sciences 2009年第2期22卷 151-156页

作者： BAO-YUN ZHANG CHAN TIAN JUN HAN chen GAO QI SHI JIAN-ming chen hui-YING JIANG WEI ZHOU AND XIAO-PING DONG State Key Laboratory for Infectious Disease Prevention and Control National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention Beijing 100052 China

Objective To establish a stable PrP^Sc panel from brain tissues of experimental hamsters infected with scrapie agent 263K for evaluating diagnostic techniques of human and animals＇ prion diseases. Methods Thirty brain tissue samples from hamsters intracerebrally infected with scrapie strain 263K and another 30 samples from normal hamsters were selected to prepare 10%, 1%, and 0.5% brain homogenates, which were aliquoted into stocks. PrP^Sc in each brain homogenate was determined by proteinase K digestions followed by Western blot assay and partially by immunohistochemistry. Stability and glycoforms of PrP^Sc were repeatedly detected by prp^SC-specific Western blots in half a year and 3 years later. Results PrPsc signals were observed in all 10% brain homogenates of infected hamsters. Twenty out of 30 stocks and 19 out of 30 stocks were PrPsc positive in 1% and 0.5% brain homogenatesof infected hamsters, respectively. TWenty-seven out of 30 stocks presented three positive bands in 10% brain homogenates, whereas none of 1% and 0.5% homogenates contained 3 bands. The detection of prpSc-specific signals stored in half a year and 3 years later demonstrated that the ratio of PrPsc positive samples and glycoforms was almost unchanged. All normal hamsters＇ brain homogenates were PrP^Sc negative. Conclusion A PrP^Sc panel of prion disease can be established, which displays reliably stable prp^Sc-specific signals and glycoforms.

关键词： TSE prp^Sc Panel Glycoforms Stability

Interfacial friction effects on sealing performances of elastomer packer

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Petroleum Science 2024年第3期21卷 2037-2047页

作者： Peng-cheng Wang ming-hui chen Jim Jenkinson Yong-Xin Song Li Sun Department of Mechanical Engineering University of HoustonHoustonTX77024USA Guren Nanomaterials Suzhou215127JiangsuChina Department of Marine Engineering Dalian Maritime UniversityDalian116026LiaoningChina

Elastomer sealing performance is of critical importance for downhole tools application including the use of fracturing(Frac)plugs during multi-stage hydraulic *** practice sealing performances of such plugs are normally evaluated through pressure tests,and in numerical simulation studies,maximum contact stress,average contact stress and contact length data are used to determine sealing quality between a packer and *** previous studies,the impact of friction forces on sealing performance is often *** work aims to fill this knowledge gap in determining the influence of friction forces on elastomer packer sealing *** first determined the most appropriate constitutive hyperelastic model for the elastomers used in frac *** we compared analytical calculation results with Finite Element Analysis simulation using a simplified tubular geometry and showed the significant influences on interfacial friction on elastomer packer stress distribution,deformation,and contact stress after *** the demonstration of validity of FEA method,we conducted systematic numerical simulation studies to show how the interfacial friction coefficients can affect the maximum contact stress,average contact stress,contact stress distribution,and maximum mises stress for an actual packer used in plug *** addition,we also demonstrated how the groove in a packer can affect packer deformation and evolvement during setting with the consideration of interfacial *** study underscores the critical role that friction forces play in Frac plug performance and provides a new dimension for optimizing packer design by controlling interfacial interactions at the packer contact surfaces.

关键词： Elastomer seal Friction Sealing performance Contact stress

A Comparative Study of the Power-law Relationship between the Pulse width and Energy of Precursor and Main Burst

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Research in Astronomy and Astrophysics 2024年第3期24卷 144-168页

作者： hui-Ying Deng Zhao-Yang Peng Jia-ming chen Dan Zhu College of Physics and Electronic Information Yunnan Normal UniversityKunming 650500China

In gamma-ray burst prompt emission,there is still no consistent conclusion if the precursor and main burst share the same *** this paper,we try to study this issue based on the relationship between pulse width and energy of the precursor and main *** systematically search the light curve data observed by Swift/BAT and Fermi/GBM,and find 13 long bursts with well-structured precursors and main *** fitting the precursor light curve of each different energy channel with the Norris function,we find that there is not only a power-law relationship between precursor width and energy,but also a power-law relationship between the ratio of the rising width to the decaying width and *** comparing the relationship between the precursors and the main burst pulses,we find that the distribution of the precursors and the relationship between the power-law indices are roughly the same as those of the main *** addition,it is found that the precursor width distribution as well as the upper limit of the pulse width ratio does not exceed 1 and both are asymmetric,which are also consistent with the main *** indicate that the precursor and the main burst are indistinguishable,and the precursor and the main burst may have the same physical origin.

关键词： methods data analysis-(stars) gamma-ray burst general-shock waves