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引种美国红枫在两种紫色土区的生长和光合特性比较

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南京林业大学学报（自然科学版） 2024年第1期48卷 97-105页

作者：魏静谭星王昌盛闫瑞李林珂宁月刘芸西南大学资源环境学院重庆400715 重庆市荣昌区岚峰林场重庆402460

【目的】研究引种美国红枫(Acer rubrum)在两种紫色土区的生长和光合特性,为美国红枫在重庆地区的发展和适地适品种提供参考。【方法】以生长在重庆地区中性紫色土区(NS1)和石灰性紫色土区(AS2)的引种美国红枫‘马莫’(***×freemanii‘... 详细信息

【目的】研究引种美国红枫(Acer rubrum)在两种紫色土区的生长和光合特性,为美国红枫在重庆地区的发展和适地适品种提供参考。【方法】以生长在重庆地区中性紫色土区(NS1)和石灰性紫色土区(AS2)的引种美国红枫‘马莫’(***×freemanii‘Marmo’)和‘金叶美国槭’(文中为‘金叶槭’***‘Aurea’)为研究对象,在生长旺盛的夏季,对美国红枫在两种紫色土区生长、叶色和光合特性进行测定。【结果】(1)‘马莫’的净株高、冠幅、叶面积与土壤碱解氮(AN)、速效钾(AK)和有机质(SOM)含量、碳氮比(C/N)呈极显著正相关(P0.05)。【结论】‘马莫’在中性紫色土区通过增加光能捕获面积提高PSⅡ光合电子传递速率和光合速率,降低有机物质的消耗,从而增强光合能力,表现出较强的生长适应性,而在石灰性紫色土区的表现较差,说明该品种对碱性紫色土壤的适应性一般;两种紫色土区‘金叶槭’的光合特性和生长均表现出较强的适应性。

关键词：引种美国红枫生长适应性光合特性叶绿素荧光参数叶色参数

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A novel batch-based LKH tree balanced algorithm for group key management

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Science China(Information Sciences) 2017年第10期60卷 255-257页

作者： Jie XU linke LI Sibian LU Huayun YIN Center for Cyber Security School of Communication and Information EngineeringUniversity of Electronic Science and Technology of China

Logical key hierarchy(LKH)is the most suitable key management scheme for a large dynamic group[1,2].Ref.[3]proposed LKH key management scheme,but it did not discuss how to keep tree balanced when membership ***.[4]pro-

关键词： LKH A novel batch-based LKH tree balanced algorithm for group key management

Transition of dynamic recrystallization mechanism during hot deformation of Incoloy 028 alloy

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Journal of Materials Science & Technology 2020年第7期42卷 241-253页

作者： XiTing Zhong Lei Wang linke Huang Feng Liu State Key Lab of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials CNPC Tubular Goods Research InstituteXi'an710077China Analytical&Testing Center Northwestern Polytechnical UniversityXi’an710072China

Dynamic recrystallization(DRX)plays significant roles in manipulating of microstructures during hot deformation and the result mechanical properties;however,the underling mechanism leading to multi scale-microstructures remains poorly ***,the DRX mechanism under wide processing conditions(i.e.950-1200°C,0.001-10 s-1)in Incoloy 028 alloy was investigated,where the relationships among flow stress,Z parameter and grain size,as well as the evolution of characteristic microstructures(grain size,sub-grain boundaries,and high angle grain boundaries),are *** the values of Z parameters decrease(corresponding to decreased flow stresses),three typical softening mechanisms successively occur,ranging from continuous DRX controlled by dislocation glide,discontinuous DRX dominated by dislocation motion(climb and cross/multiple slip)and grain boundary migration,to dynamic normal/abnormal grain growth resulting from grain boundary migration,with transition regions where two adjacent mechanisms occur ***,these above three softening mechanisms result in ultrafine,fine and coarse grains,*** present findings demonstrate a comprehensive understanding of DRX mechanism over a wide range of processing conditions,and further provide a new guideline for preparing single crystals.

关键词： Hot deformation Dynamic recrystallization Microstructure evolution Incoloy 028

四川盆地川中—川西过渡带中侏罗统沙溪庙组致密砂岩相对优质储层成因机制

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吉林大学学报（地球科学版） 2024年第2期54卷 371-388页

作者：宋林珂刘四兵曾青高周栋唐大海王锦西中国石油西南油气田公司致密油气勘探开发项目部成都610059 油气藏地质及开发工程国家重点实验室(成都理工大学) 成都610059

川中—川西过渡带沙溪庙组天然气勘探潜力巨大,是四川盆地近几年勘探的热点。目前,制约沙溪庙组致密砂岩天然气勘探开发的问题较多,其中,“相对优质储层”的形成机理和综合预测是亟需解决的关键问题之一。针对这一科学问题,本次研究通... 详细信息

川中—川西过渡带沙溪庙组天然气勘探潜力巨大,是四川盆地近几年勘探的热点。目前,制约沙溪庙组致密砂岩天然气勘探开发的问题较多,其中,“相对优质储层”的形成机理和综合预测是亟需解决的关键问题之一。针对这一科学问题,本次研究通过系统的物性分析、铸体薄片鉴定、扫描电镜分析以及储层地球化学分析等,开展了研究区沙溪庙组相对优质储层成因机制研究。研究结果表明:沙溪庙组致密砂岩以岩屑长石砂岩和长石岩屑砂岩为主。沙二段砂岩石英平均体积分数为35.27%,长石平均体积分数为35.37%,岩屑平均体积分数为29.36%,沙一段砂岩石英平均体积分数为37.79%,长石平均体积分数为24.01%,岩屑平均体积分数为38.20%,沙一段长石体积分数较高,沙二段岩屑体积分数较高。沙二段以变质岩岩屑为主(占岩屑体积分数的55%),沙一段则以岩浆岩岩屑为主(占岩屑体积分数的43%)。储层孔隙类型以原生孔为主,长石溶蚀孔为辅,沙一段具有相对更高比例的原生孔和裂隙孔。沙二段砂岩中38.00%的样品孔隙度大于12%,25.25%的样品渗透率大于1×10^(-3)μm^(2),沙一段砂岩仅3.09%的样品孔隙度大于12%,但41.22%的样品渗透率大于1×10^(-3)μm^(2)。总体表现为致密背景下发育一定的相对优质储层。其中沙二段储层孔隙度发育较好,而沙一段储层渗透性更佳,说明沙一段储层孔隙结构相对较好。沙溪庙组致密砂岩储层发育受控于岩矿组合-烃源体系-成岩系统。岩矿组合为成岩作用的演化提供物质基础,烃源体系决定溶蚀作用发育的强度,并为砂岩中主要自生矿物的沉淀提供必要的离子来源;成岩系统的开放程度则决定了体系内外离子的带进带出,进而影响了溶蚀作用和相应成岩产物的沉淀。沙二和沙一段砂岩岩矿组合的差异、沉积环境的不同、烃源体系以及成岩系统的开放程度是导致其成岩作用差异的主要原因。综上认为,高能沉积环境、早期保持性成岩作用(孔隙衬垫绿泥石)、多期次和多种类型的溶蚀作用以及局部微裂缝的发育改造,是研究区沙溪庙组相对优质储层发育的主要机制。

关键词：川中—川西过渡带沙溪庙组致密砂岩相对优质储层成因机制四川盆地

Materials design by generalized stability

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Journal of Materials Science & Technology 2023年第16期147卷 153-164页

作者： Yu Zhang Haoran Peng linke Huang Feng Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityShaanxi 710072China Northwest Institute for Nonferrous Metal Research Xi’an 710016China Analytical&Testing Center Northwestern Polytechnical UniversityShaanxi 710072China

***,Understanding and predicting microstructure and its relationship with the mechanical properties of metallic materials require detailed knowledge of phase transformations(PTs)and plastic deformations(PDs).These two processes,as central topics in material science,can be fundamentally described to a large extent by a framework of thermodynamic and kinetics(thermo-kinetics).The situation of PTs arises when the microstructure is losing phase stability,whereas the issue of PDs corresponds to the break of mechanical stability,all of which can be uniformly defined as the so-called loss of thermodynamic stability(TS).In this context,the higher TS will lead to the higher driving force G essentially required for the PT and/or PD forming and/or changing the *** the case of PTs,extensive examples showing the high TS can be found,such as martensite transformations(MTs)upon continuous cooling or strain[1,2],coherent precipitation[3,4],so-called Schwarz crystal[5],etc.

关键词： microstructure martensite stability

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基于多源数据的通勤绿道选线研究

中国园林 2024年第8期40卷 97-103页

作者：李林柯吴晓华应君赵若茜李昂扬浙江农林大学风景园林与建筑学院杭州311300 浙江省新型重点专业智库——浙江农林大学生态文明研究院杭州311300

通勤绿道对于鼓励居民健康低碳出行、缓解城市交通拥堵具有非常重要的作用。随着互联网的发展和数据的公开,获取人们日常通勤数据,优化城市通勤绿道成为可能。对此,以杭州市未来科技城核心片区为例,探讨基于居民通勤行为大数据的绿道选... 详细信息

通勤绿道对于鼓励居民健康低碳出行、缓解城市交通拥堵具有非常重要的作用。随着互联网的发展和数据的公开,获取人们日常通勤数据,优化城市通勤绿道成为可能。对此,以杭州市未来科技城核心片区为例,探讨基于居民通勤行为大数据的绿道选线方法,首先通过人们的出行行为分析确定绿道关键接驳点,其次通过建设适宜性分析建立综合阻力模型,运用Linkage Mapper工具进行选线模拟,最后对选线模拟结果优化确定最终选线。根据通勤绿道所依托道路的道路类型,将通勤绿道分为三级,形成了“八主七次十二支”的绿道通勤网络。这为未来城市通勤绿道的规划提供了一种新的思路,将有利于实现居民绿色健康通勤,完善城市绿道网络体系。

关键词：风景园林通勤绿道通勤行为选线多源数据

Oxygen tolerance capacity of upflow anaerobic solid-state(UASS) with anaerobic filter(AF) system

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Journal of Environmental Sciences 2016年第7期28卷 200-206页

作者： Yao Meng Carsten Jost Jan Mumme Kaijun Wang Bernd linke State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Department Bioengineering Leibniz Institute for Agricultural Engineering UK Biochar Centre School of Geo Sciences University of Edinburgh

In order to investigate the oxygen tolerance capacity of upflow anaerobic solid-state（UASS）with anaerobic filter（AF） system, the effect of microaeration on thermophilic anaerobic digestion of maize straw was investigated under batch conditions and in the UASS with AF system. Aeration intensities of 0–431 m L O2/gvswere conducted as pretreatment under batch conditions. Aeration pretreatment obviously enhanced anaerobic digestion and an aeration intensity of 431 m L O2/gvsincreased the methane yield by 82.2%. Aeration intensities of 0–355 m L O2/gvswere conducted in the process liquor circulation of the UASS with AF system. Dissolved oxygen（DO） of UASS and AF reactors kept around 1.39 ±0.27 and 0.99 ± 0.38 mg/L, respectively. p H was relatively stable around 7.11 ± 0.04. Volatile fatty acids and soluble chemical oxygen demand concentration in UASS reactor were higher than those in AF reactor. Methane yield of the whole system was almost stable at 85 ± 7 m L/gvs as aeration intensity increased step by step. The UASS with AF system showed good oxygen tolerance capacity.

关键词： Anaerobic digestion Oxygen tolerance capacity UASS Maize straw Microaeration Solid-state

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大气中有机磷酸酯的赋存状况及环境行为

环境化学 2024年第1期43卷 174-185页

作者：邢戎光张蓬纪浩石仞葛林科马宏瑞陕西科技大学环境科学与工程学院西安710021

有机磷酸酯(organophosphate esters,OPEs)作为阻燃剂和增塑剂添加在塑料、织物和建筑材料中,其产量逐年递增. OPEs曾经被认为是溴代阻燃剂(BFRs)的有效替代品;然而,最近的研究指出其在大气中的含量比BFRs高1—3个数量级,且某些OPEs化... 详细信息

有机磷酸酯(organophosphate esters,OPEs)作为阻燃剂和增塑剂添加在塑料、织物和建筑材料中,其产量逐年递增. OPEs曾经被认为是溴代阻燃剂(BFRs)的有效替代品;然而,最近的研究指出其在大气中的含量比BFRs高1—3个数量级,且某些OPEs化合物半衰期长,具有显著的毒性效应和长距离迁移潜力,因此,OPEs日益成为一类备受关注的全球性新型有机污染物,“更安全”的替代品的认知被质疑.本文总结了大气中OPEs的赋存状况、气-粒分配、长距离传输和光氧化等方面的研究.通过比较世界各地区大气OPEs的含量和组成特征发现,工业排放源、长距离传输和气象条件是影响大气中OPEs空间分布趋势的重要因素.尽管颗粒态对长距离传输、归趋和风险评价具有重要的科学意义,然而,气-粒分配模型研究和实际监测较为缺乏,模型结果和监测计算结果之间差异较大,推测模型的准确性可能受理化性质、气象条件以及采样技术的影响. OPEs在大气中光氧化降解的研究方兴未艾,仍需继续深入发掘多种环境因素的影响,推测降解路径和产物.因此,将来亟待发展适合OPEs的预测模型,开发新型的采样技术,揭示其光氧化降解路径和产物,以期更好地理解OPEs在大气中的环境赋存和行为规律,为环境质量管理提供理论支持.

关键词：有机磷酸酯大气赋存状况气-粒分配模型环境行为

Prediction of Outdoor Noise Propagation Induced By Single-Phase Power Transformers

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Sound & Vibration 2019年第1期53卷 2-13页

作者： Xueyun Ruan Wei Huang linke Zhang Yan Gao School of Mechanical Engineering Anhui University of Science and TechnologyAnhui Huainan232000China Key Laboratory of Noise and Vibration Research Institute of AcousticsChinese Academy of SciencesBeijing100190China School of Energy and Power Engineering Wuhan University of TechnologyHubei Wuhan430063China

Outdoor power transformers are one of the most pervasive noise sources in power transmission and distribution *** prediction of outdoor noise propagation plays a dominant role for the evaluation and control of noise relevant to the transformer *** this paper surface vibration tests are carried out on a scale model of a single-phase transformer tank wall at different excitation *** phase and amplitude of test data are found to be randomly distributed when the excitation frequency exceeds the seventh mode frequency,which allows the single-phase power transformer to be simplified as incoherent point *** outdoor-coherent model is subsequently developed and incorporated with the image source method to investigate noise propagation from single-phase power transformers,due to the occurrence of multiple reflections and diffractions in the propagation path of each point *** proposed model is used to calculate the sound field of the power transformer group by exploiting the additional phase *** comparison with the ISO9613 model and the boundary element method,it is found that the proposed coherent image source method leads to more accurate prediction results,and hence better performance for the prediction of the outdoor noise induced by single-phase power transformers.

关键词： Single-phase transformer surface vibration scale model noise prediction coherent image source method