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Plasma Science and Technology 2022年第3期24卷 33-40页

作者： Qifan ZHANG Yiping HAN Qinlu dong chang dong School of Physics and Optoelectronic Engineering Xidian UniversityXi'an 710071People's Republic of China

The plasma sheath covering hypersonic vehicles has a significant effect on the propagation of electromagnetic *** on the calculation of the flow field of a conical cylindrical,this work studies the propagation of electromagnetic waves in plasma sheath at L-band and Ku-band,and discusses the propagation characteristics in the head,side and tail of the *** dielectric properties of plasma sheath are related to flight speed and altitude.A flight condition corresponds to a unique distribution of dielectric *** the conical cylindrical,the results show that flight speed is generally negatively correlated with the transmissivity of the plasma *** reflection characteristics of electromagnetic waves at the L-band and Kuband when obliquely incident to the plasma sheath show a downward *** the frequency is increased to Ku-band,the propagation characteristics of electromagnetic waves in the plasma sheath are related to the position of the sheath.

关键词： plasma sheath reflection and transmission flow field

Solitary Wave Simulated by the Water Column Collapsing Method

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China Ocean Engineering 2022年第3期36卷 395-402页

作者： WANG Jin dong chang-ming LIU Qing-jun ZUO Qi-hua School of Marine Sciemces Nanjing University of Information Science&TechnologyNanjing 210044China Southern Ocean Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China Nanjing Xinda Institute of Safety and Emergency Management Nanjing 210044China Nanjing Hydraulic Research Institute Nanjing 210029China

Although solitary waves with large ratio of wave height to water depth are difficult to produce in laboratory settings by traditional wave generating methods,a water column collapsing(WCC)method can be *** study uses the WCC method to produce large solitary waves and through a series of experiments,an empirical equation is developed that considers wave height and water depth in addition to water column height and *** solitary waves are studied through wavelet *** from this analysis demonstrate that the ratios between the initial lab-oratory-generated solitary wave and its theoretical counterpart range from 0.2−*** using the results,a new solitary wave generating law is derived and can be applied to future solitary wave laboratory studies.

关键词： water column collapsing solitary wave wavelet spectrum waveform evolution generating law

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渐开线变齿厚齿轮啮合冲击分析

兰州理工大学学报 2024年第4期50卷 29-35页

作者：刘永平任忠涛董长斌魏永峭魏帅兰州理工大学机电工程学院甘肃兰州730050

基于弹性接触动力学理论和齿轮传动物理模型,对渐开线变齿厚齿轮啮合冲击问题进行了分析,建立了变齿厚齿轮全齿啮合接触冲击模型.通过模拟轮齿啮合接触状态,对轮齿啮合区域展开了讨论,利用LS-DYNA软件进行接触碰撞分析,分别研究了冲击... 详细信息

基于弹性接触动力学理论和齿轮传动物理模型,对渐开线变齿厚齿轮啮合冲击问题进行了分析,建立了变齿厚齿轮全齿啮合接触冲击模型.通过模拟轮齿啮合接触状态,对轮齿啮合区域展开了讨论,利用LS-DYNA软件进行接触碰撞分析,分别研究了冲击合力和冲击应力随转速和冲击位置的变化规律.结果表明:转速和冲击位置对冲击合力和冲击应力影响显著,且冲击最大应力主要集中在齿顶和轮齿的大小端附近;转速越大,轮齿受载面与非受载面之间的冲击应力相差越大.

关键词：渐开线变齿厚齿轮啮合冲击接触分析冲击应力

经脐单孔3D腔镜下肝总管-空肠改良Warren吻合术治疗儿童胆总管囊肿的效果观察

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罕少疾病杂志 2024年第8期31卷 78-79,85页

作者：常栋喆周良徐科耿宪杰郑州大学附属儿童医院、河南省儿童医院、郑州儿童医院普通外科河南郑州450000

目的探究经脐单孔3D腔镜下肝总管-空肠改良Warren吻合术治疗儿童胆总管囊肿的疗效。方法选取河南省儿童医院2012年8月至2022年8月收治的90例儿童胆总管囊肿患儿,使用随机数字法分为观察组(n=45)和对照组(n=45),观察组实施经脐单孔3D腔... 详细信息

目的探究经脐单孔3D腔镜下肝总管-空肠改良Warren吻合术治疗儿童胆总管囊肿的疗效。方法选取河南省儿童医院2012年8月至2022年8月收治的90例儿童胆总管囊肿患儿,使用随机数字法分为观察组(n=45)和对照组(n=45),观察组实施经脐单孔3D腔镜下肝总管-空肠改良Warren吻合术治疗,对照组行Roux-en-Y胆肠吻合术治疗,对比两组治疗有效率、手术相关指标、肝功能及术后并发症。结果观察组治疗有效率95.56%高于对照组82.22%(P<0.05);观察组手术时间、术中出血量、术后摄食时间及住院时间均低于对照组(P<0.05);观察组肝功能指标和术后并发症发生率均低于对照组(P<0.05)。结论针对儿童胆总管囊肿患儿,采用经脐单孔3D腔镜下肝总管-空肠改良Warren吻合术治疗具有良好的效果,在提升临床疗效,改善相关手术指标和肝功能指标,减少并发症等方面具有积极意义。

关键词：经脐单孔3D腔镜肝总管-空肠吻合改良Warren吻合术胆总管囊肿

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Effect of Al addition on corrosion behavior of high-purity Mg in terms of processing history

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Journal of Magnesium and Alloys 2023年第3期11卷 851-868页

作者： Sang Kyu Woo Byeong-Chan Suh Ha Sik Kim chang dong Yim Helmholtz Zentrum Hereon Max-Planck-Straße 1Geesthacht D-21502Germany Korea Institute of Materials Science 797 Changwondae-roSeongsan-guChangwonGyeongnam 51508Republic of Korea University of Science and Technology 217 Gajeong-roYuseong-guDaejeon 34113Republic of Korea

In this study,the effects of Al addition on the corrosion behavior of pure Mg with controlled impurity contents were systematically analyzed according to the processing *** results revealed that the corrosion behavior of high-purity Mg-Al alloys is strongly related to changes in the microstructure,including theβphase and Al-Mn or Al-Fe phases,and the protectiveness of the surface film according to the Al content and processing *** the as-cast alloys,the corrosion rate increased due to the increase ofβphase as the Al content increased,but in the as-extruded alloys,the corrosion rate,which was high due to intermetallic compounds caused by impurities in the low Al alloy,decreased as the Al content increased,and then increased *** is due to the combined effect of the increase of theβphase and decrease of the impurity effect,and the increase of the dissolved Al *** results suggest that it is necessary to analyze the effect of alloying elements on the corrosion behavior of pure Mg with information concerning the impurity content and processing history.

关键词： Mg High purity Mg-Al alloys Processing history Micro-galvanic Surface film

不同生境下烤烟三段式育苗微生物群落变化及抗逆酶活分析

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生物技术通报 2024年第4期40卷 242-254页

作者：王颢杰常栋李俊营孟颢光蒋士君周硕野崔江宽河南农业大学植物保护学院郑州450046 河南省烟草公司平顶山市公司平顶山467000 河南省烟草专卖局(公司) 郑州450018

【目的】为解析三段式育苗对烟苗根际微生物多样性和抗逆酶活性的影响。【方法】以中烟100为供试品种,以常规漂浮育苗为对照,设置三段式育苗。通过监测工厂化四联体育苗大棚中烟苗的生长发育情况,系统分析了三段式育苗方式对育苗环境,... 详细信息

【目的】为解析三段式育苗对烟苗根际微生物多样性和抗逆酶活性的影响。【方法】以中烟100为供试品种,以常规漂浮育苗为对照,设置三段式育苗。通过监测工厂化四联体育苗大棚中烟苗的生长发育情况,系统分析了三段式育苗方式对育苗环境,育苗池、基质和根系微生物多样性,烟苗农艺性状和抗逆酶活性的影响。同时,追溯分析三段式育苗对于田间烟草根际土壤微生物多样性的影响。【结果】幼苗期,三段式育苗方式相对于漂浮育苗对照,改善了育苗池水体的理化性状,降低了育苗大棚内的温差和湿度水平,日均温差由19.23℃下降至17.95℃,日均湿度由75.17%RH下降至69.53%RH;成苗期,三段式育苗增加了育苗池水体中的短波单胞菌属(Brevundimonas)和赖氨酸芽孢杆菌属(Lysinibacillus)的丰度,分别为漂浮育苗的13.90倍和4.66倍。增加了烟苗的鲜重、根长、侧根数、CAT酶活性、SOD酶活性、POD酶活性、根活力和成苗率,较漂浮育苗对照分别提高了34.33%、34.37%、36.41%、31.91%、25.34%、58.07%、29.08%和10.91%,MDA含量降低了22.31%;大田期,提升了烟草根际土壤微生物子囊菌门和青梅属的丰度,创造了更有利的烟草生长环境。【结论】三段式育苗通过改善育苗环境,增加了烟苗根际有益菌群的丰度,显著提高了烟苗的成苗期农艺性状和抗逆酶活性,从而提升烟苗素质。

关键词：烟草三段式育苗烟苗根际微生物烟苗根活力

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Identification and functional analysis of arabinogalactan protein expressed in pear pollen tubes

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Journal of Integrative Agriculture 2023年第3期22卷 776-789页

作者： JIAO Hui-jun WANG Hong-wei RAN Kun dong Xiao-chang dong Ran WEI Shu-wei WANG Shao-min Shandong Institute of Pomology Tai’an 271000P.R.China

Arabinogalactan proteins(AGPs)are widely distributed in the plant kingdom and play a vital role during the process of plant sexual *** this study,we performed a comprehensive identification of the PbrAGPs expressed in pear pollen and further explored their influences on pollen tube *** the 187 PbrAGPs that were found to be expressed in pear pollen tubes,38 PbrAGPs were specifically expressed in pollen according to the RNA-seq *** PbrAGPs were divided into two groups of highly expressed and specifically expressed in pear *** further tested their expression patterns using RT-PCR and *** of the PbrAGPs were expressed in multiple tissues and their expression levels were consistent with reads per kilobase per million map reads(RPKM)values during pollen tube growth,implying that PbrAGPs might be involved in the regulation of pear pollen tube *** also constructed phylogenetic trees to identify the functional genes in pear pollen tube ***,19 PbrAGPs(PbrAGP1 to PbrAGP19)were selected to test their influences on pollen tube *** proteins of the 19 PbrAGP-His were purified and used to treat pear pollen,and 11 of the PbrAGP-His recombinant proteins could promote pear pollen tube ***,pollen tube growth was inhibited when the expression levels of PbrAGP1 and PbrAGP5 were knocked down using an antisense oligonucleotide ***1 and PbrAGP5 were localized in the plasma membrane and might not alter the distribution of pectin in the pollen *** summary,this study identified the PbrAGPs expressed in pear pollen and lays the foundation for further exploring their functions in pollen tube growth.

关键词： arabinogalactan proteins pear pollen tube antisense oligodeoxynucleotides sexual reproduction

Molecular mechanisms underlying the toxicity and detoxification of trace metals and metalloids in plants

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Journal of Integrative Plant Biology 2023年第2期65卷 570-593页

作者： Zhong Tang Han-Qing Wang Jie Chen Jia-dong chang Fang-Jie Zhao State Key Laboratory of Crop Genetics and Germplasm Enhancement College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China

Plants take up a wide range of trace metals/metalloids(hereinafter referred to as trace metals)from the soil,some of which are essential but become toxic at high concentrations(e.g.,Cu,Zn,Ni,Co),while others are non-essential and toxic even at relatively low concentrations(e.g.,As,Cd,Cr,Pb,and Hg).Soil contamination of trace metals is an increasing problem worldwide due to intensifying human *** metal contamination can cause toxicity and growth inhibition in plants,as well as accumulation in the edible parts to levels that threatens food safety and human *** the mechanisms of trace metal toxicity and how plants respond to trace metal stress is important for improving plant growth and food safety in contaminated *** accumulation of excess trace metals in plants can cause oxidative stress,genotoxicity,programmed cell death,and disturbance in multiple physiological *** have evolved various strategies to detoxify trace metals through cell-wall binding,complexation,vacuolar sequestration,efflux,and *** signal transduction pathways and regulatory responses are involved in plants challenged with trace metal *** this review,we discuss the recent progress in understanding the molecular mechanisms involved in trace metal toxicity,detoxification,and regulation,as well as strategies to enhance plant resistance to trace metal stresses and reduce toxic metal accumulation in food crops.

关键词： detoxification food safety stress response trace metals/metalloids toxic mechanisms

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博孜2402井钻井提速关键技术

西部探矿工程 2024年第4期36卷 25-29,33页

作者：王言泉郑智冬刘立超吴彪李长东窦华进中国石油集团渤海钻探工程有限公司第三钻井工程分公司天津300280

目前塔里木博孜1区块部署的井多为五开井身结构,平均井深7000m以上。地质构造复杂,施工难度大,事故复杂频发,周期普遍在400d以上。该区块吉迪克组、库姆格列木群盐层段以及目的层事故频发成为区块钻井难题,尤其是上部巨厚砾石层严重制... 详细信息

目前塔里木博孜1区块部署的井多为五开井身结构,平均井深7000m以上。地质构造复杂,施工难度大,事故复杂频发,周期普遍在400d以上。该区块吉迪克组、库姆格列木群盐层段以及目的层事故频发成为区块钻井难题,尤其是上部巨厚砾石层严重制约区域资源高效勘探开发,实钻表现为机械钻速慢、单只钻头行程进尺低、因憋跳钻引发井下钻具事故频发。博孜2402井从井身质量优化、钻头选型技术、钻具组合优化技术、钻井液体系优选、盐层卡层技术等方面着手,形成了博孜2402井钻井提速关键技术,该井最终以钻井周期253.88d,钻完井周期303.88d,创博孜1区块钻完井周期记录,博孜2402井关键钻井技术,可为博孜1区块钻井提供技术支持,建议进行推广。

关键词：博孜1区块海博瑞钻头钻头选型钻具组合钻井提速

A deep learning-based method for segmentation and quantitative characterization of microstructures in weathering steel from sequential scanning electron microscope images

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Journal of Iron and Steel Research International 2022年第5期29卷 836-845页

作者： Bing Han Wei-hao Wan Dan-dan Sun Cai-chang dong Lei Zhao Hai-zhou Wang Beijing Advanced Innovation Center for Materials Genome Engineering Central Iron&Steel Research InstituteBeijing100081China Qingdao NCS Testing&Corrosion Protection Technology Co. Ltd.Qingdao266071ShandongChina Beijing Key Laboratory of Metal Materials Characterization Central Iron&Steel Research InstituteBeijing100081China

Microstructural classification is typically done manually by human experts,which gives rise to uncertainties due to subjectivity and reduces the overall efficiency.A high-throughput characterization is proposed based on deep learning,rapid acquisition technology,and mathematical statistics for the recognition,segmentation,and quantification of microstructure in weathering *** segmentation results showed that this method was accurate and efficient,and the segmentation of inclusions and pearlite phase achieved accuracy of 89.95%and 90.86%,*** time required for batch processing by MIPAR software involving thresholding segmentation,morphological processing,and small area deletion was 1.05 s for a single *** comparison,our system required only 0.102 s,which is ten times faster than the commercial *** quantification results were extracted from large volumes of sequential image data(150 mm^(2),62,216 images,1024×1024 pixels),which ensure comprehensive *** information,such as three-dimensional density distribution and the frequency of the minimum spatial distance of inclusions on the sample surface of 150 mm^(2),were quantified by extracting the coordinates and sizes of individual features.A refined characterization method for two-dimensional structures and spatial information that is unattainable when performing manually or with software is *** will be useful for understanding properties or behaviors of weathering steel,and reducing the resort to physical testing.

关键词： Deep learning High-throughput Microstructure Sequential image Rapid acquisition Quantitative characterization Segmentation