检索结果-南通市图书馆

On the Features of Thermal Convection in a Compressible Gas

Fluid Dynamics & Materials Processing 2024年第5期20卷 957-974页

作者： igor b.Palymskiy Physics Department Siberian State University of Telecommunications and Information SciencesNovosibirsk City630102Russia Physics Department Siberian State University of Geosystems and TechnologiesNovosibirsk City630108Russia

The fully nonlinear equations of gas dynamics are solved in the framework of a numerical approach in order to study the stability of the steady mode of Rayleigh-bénard convection in compressible,viscous and heat-conducting gases encapsulated in containers with no-slip boundaries and isothermal top and bottom *** initial linear temperature profile is assumed.A map of the possible convective modes is presented assuming the height of the region and the value of the temperature gradient as influential *** a relatively small height,isobaric convection is found to take place,which is taken over by an adiabatic mode when the height exceeds the critical value,or by a super-adiabatic mode in case of a relatively high temperature *** the adiabatic mode,convective flow develops due to adiabatic processes given a stable initial *** analytic formula for the critical height of the region is derived taking into account and neglecting the dependence of the gas viscosity on the ***,an analytic formula is obtained for the upper boundary of the region of applicability of the boussinesq approximation for incompressible *** models for compressible gases are relevant to practical situations such as the study of convective flows in spatially extended gas mixtures when dealing with safety issues related to hydrocarbons stored in gas stations.A dangerous situation arises when the tank is almost empty but some hydrocarbon is left at the bottom of the *** the presence of convective flows,the vaporized fuel is mixed with the oxidizer(air)forming a gas-vapor ***,if the volumetric concentration of fuel vapor(hydrocarbon)is in the interval between the lower and upper concentration limits of ignition,then the gas-vapor mixture becomes explosive and any accidental spark is sufficient to cause an emergency.

关键词： Rayleigh-bénard convection gas stable stratification unstable stratification temperature gradient

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Hybrid bimetallic cluster ZrO2/Rh@N,S co-doped porous carbon nanosheets for efficient hydrogen evolution in acid electrolytes

引用

Tungsten 2024年第4期6卷 657-662页

作者： Xin-Yi Zhang igor V.Zatovsky Jun-Ming Cao Xing-Long Wu Faculty of Chemistry Northeast Normal University F.D.Ovcharenko Institute of biocolloidal Chemistry NAS Ukraine MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal University

Acid hydrogen evolution reaction (HER) is a critical energy conversion process,which is significantly important in hydrogen energy manufacturing and storage [1].Although the performance of noble metal platinum (Pt)-based catalysts in acidic HER is well known,the challenges are high cost,limited reserves,poor stability,and susceptibility to toxic substances [2].Therefore,it is urgent to design and manufacture acidic HER catalysts with high reactivity,high stability,and low cost.

关键词：

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Identifying the stability of housekeeping genes to be used for the quantitative real-time PCR normalization in retinal tissue of streptozotocin-induced diabetic rats

引用

International Journal of Ophthalmology(English edition) 2024年第5期17卷 794-805页

作者： Muhammad Zulfiqah Sadikan Nurul Alimah Abdul Nasir Mohammad Johari Ibahim igor Iezhitsa Renu Agarwal Department of Pharmacology Faculty of MedicineManipal University College Malaysia(MUCM)Bukit BaruMelaka 75150Malaysia Centre for Neuroscience Research(NeuRon) Faculty of MedicineUniversiti Teknologi MARASungai Buloh CampusSungai BulohSelangor 47000Malaysia Department of Medical Education Faculty of MedicineUniversiti Teknologi MARASungai Buloh CampusSungai BulohSelangor 47000Malaysia Department of biochemistry and Molecular Medicine Faculty of MedicineUniversiti Teknologi MARASungai Buloh CampusSungai BulohSelangor 47000Malaysia School of Medicine International Medical UniversityBukit JalilKuala Lumpur 57000Malaysia Department of Pharmacology and bioinformatics Volgograd State Medical UniversityVolgograd 400131Russia

AIM:To investigate the stability of the seven housekeeping genes:beta-actin(Actb),glyceraldehyde-3-phosphate dehydrogenase(GAPDH),18s ribosomal unit 5(18s),cyclophilin A(CycA),hypoxanthine-guanine phosphoribosyl transferase(HPRT),ribosomal protein large P0(36b4)and terminal uridylyl transferase 1(U6)in the diabetic retinal tissue of rat ***:The expression of these seven genes in rat retinal tissues was determined using real-time quantitative reverse transcription polymerase chain reaction(RT-qPCR)in two groups;normal control rats and streptozotocininduced diabetic *** stability analysis of gene expression was investigated using geNorm,NormFinder,bestKeeper,and comparative delta-Ct(ΔCt)***:The 36b4 gene was stably expressed in the retinal tissues of normal control animals;however,it was less stable in diabetic *** 18s gene was expressed consistently in both normal control and diabetic rats’retinal *** this gene was the best reference for data normalisation in RT-qPCR studies that used the retinal tissue of streptozotocin-induced diabetic ***,there was no ideal gene stably expressed for use in all experimental ***:Identifying relevant genes is a need for achieving RT-qPCR validity and reliability and must be appropriately achieved based on a specific experimental setting.

关键词： housekeeping genes stability real-time reverse transcription polymerase chain reaction retinal tissue streptozotocin-induced diabetic rats

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Mn微合金化对Ti-Al-Mo-Zr-Fe-b合金组织演变和力学性能的影响

引用

稀有金属材料与工程 2024年第6期53卷 1555-1565页

作者：何苗霞燕迟董月成常辉 Alexandrov igor V 南京工业大学材料科学与工程学院新材料研究院江苏南京211816 乌法理工大学材料科学与金属物理系俄罗斯乌法450008

通过OM、EbSD和TEM等研究了Mn微合金化对新型近αTi-Al-Mo-Zr-Fe-b合金微观组织和力学性能的影响。结果表明:添加0.5%(质量分数)的Mn元素可以将合金的铸态微观组织从3.28μm细化到2.65μm,使其抗拉伸强度从882 MPa提高到966 MPa,但延伸... 详细信息

通过OM、EbSD和TEM等研究了Mn微合金化对新型近αTi-Al-Mo-Zr-Fe-b合金微观组织和力学性能的影响。结果表明:添加0.5%(质量分数)的Mn元素可以将合金的铸态微观组织从3.28μm细化到2.65μm,使其抗拉伸强度从882 MPa提高到966 MPa,但延伸率从7.8%下降到5.1%。锻造后的2种合金的晶粒尺寸趋于一致,微观组织趋于等轴化且Mn微合金化后的组织更加均匀。锻造后,Ti-Al-Mo-Zr-Fe-b合金的抗拉伸强度和延伸率增加到966 MPa和16.4%,而含有0.5%(质量分数)Mn元素的合金具有更高的抗拉伸强度,达到了1079 MPa,同时延伸率达到了15.8%。结论表明,强度的提高可以归因于Mn元素的固溶强化效应,同时Mn微合金化处理使合金中的Al元素富集于α相,有利于提高合金的强度和塑性。

关键词： Mn微合金化近α钛合金组织演变力学性能

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Plant community on a volcano mountaintop reveals unique high-altitude vegetation in southeastern brazil

引用

Journal of Mountain Science 2024年第9期21卷 3018-3030页

作者： igor Musauer KESSOUS Ruy JoséValka ALVES Nílber Gonçalves da SILVA Amilcar Walter SAPORETTI JUNIOR biodiversity Laboratory Federal Institute of EducationScience and Technology of Southern Minas Gerais(IFSULDEMINAS)Av.Dirce Pereira Rosa300-Jardim Esperança37713-100Poços de CaldasMGBrazil Department of botany National MuseumFederal University of Rio de JaneiroQuinta da Boa Vista s.n.São Cristóvão20949-040Rio de JaneiroRJBrazil Gothenburg Global biodiversity Centre Carl Skottsbergs Gata 22BSE 41319GothenburgSweden

Mountains exhibit a high degree of endemism and diversity,however,quantifying their biodiversity can be *** to islands,species isolation in mountainous regions results in comparable patterns of evolution and extinction,rendering their biodiversity unique and highly susceptible to anthropogenic *** topographic relief in mountains plays a crucial role in creating habitat complexity,which in turn contribute to high plant ***,we investigated plant diversity in the volcano mountaintop vegetation on the Poços de Caldas Plateau,a region situated in the ecotone between the Atlantic Forest and Cerrado,characterized by natural radiation and significant anthropogenic *** employed an automated approach through the filtering of georeferenced and non-georeferenced data to obtain a list of plant species in the ***,we statistically investigated the similarity among different high-altitude vegetations belonging to the campos de altitude from the Atlantic Forest and campos rupestres from the *** plateau exhibits high plant diversity,including 1,659 specific and infraspecific taxa,especially belonging to Asteraceae and *** analyses suggest that geographical distance is a strong predictor of dissimilarity and that the Poços de Caldas Plateau is more floristically related to the campos rupestres,despite being associated with campos de *** region possesses a unique set of biodiversity,indicating that it may be a distinct ***,we hypothesize that Pleistocene events likely influenced the conformation of the current floristic composition in the region through species interchange between the Cerrado and Atlantic *** study also highlights the few taxa assessed for conservation status and anthropogenic threats that this habitat is facing.

关键词： Atlantic Forest biogeography Cerrado Community ecology Grassland

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

2022年欧洲血管外科学会(ESVS)下肢慢性静脉疾病管理临床实践指南(全译)

引用

中华血管外科杂志 2023年第1期8卷 76-158页

作者： Marianne G.De Maeseneer Stavros K.Kakkos Thomas Aherne Niels baekgaard Stephen black Lena blomgren Athanasios Giannoukas Manjit Gohel Rick de Graaf Claudine Hamel-Desnos Arkadiusz Jawien Aleksandra Jaworucka-Kaczorowska Christopher R.Lattimer Giovanni Mosti Thomas Noppeney Marie JoseevanRijn Gerard Stansby 无 Philippe Kolh Frederico bastos Gongalves Nabil Chakfé Raphael Coscas Gert J.deborst Nuno V.Dias Robert J.Hinchliffe igor b.koncar Jes S.Lindholt Santi Trimarchi Rikka Tulamo Christopher P.Twine Frank Vermassen Anders Wanhainen Martin bjorck Nicos Labropoulos Fedor Lurie Armando Mansilha Isaac K.Nyamekye Marta Ramirez Ortega Jorge H.Ulloa Tomasz Urbanek Andre M.van Rij Marc E.Vuylsteke 荷兰鹿特丹伊拉斯谟医疗中心皮肤科希腊帕特雷帕特雷大学血管外科爱尔兰科尔克大学医院和爱尔兰国立大学戈尔韦分校血管外科丹麦哥本哈根大学根措夫特医院和国家教学研究医院血管外科英国伦敦盖伊和圣托马斯医院及国王学院瑞典厄勒布罗大学医学院心血管和胸外科希腊塞萨利大学健康科学学院医学院拉里萨大学医院血管外科英国伦敦剑桥大学医院和帝国理工学院德国弗里德里希沙芬诊所诊断和介入放射科法国巴黎圣约瑟夫医院集团法国卡昂圣马丁私立医院血管内科波兰托伦市路德维克·赖德吉耶医学院尼古拉·哥白尼大学血管外科和血管学系波兰戈佐市静脉和美容医学中心、外科和妇科中心伦敦西北大学医疗保健NHS信托基金会英国伦敦帝国学院意大利卢卡Maria Domenica barbantini诊所血管科纽伦堡MarthaMaria医院血管和血管内外科德国雷根斯堡大学医院血管和内皮外科荷兰鹿特丹伊拉斯谟医疗中心血管外科英国泰恩河畔纽卡斯尔弗里曼医院纽卡斯尔大学 ESVS Guidelines Committee 比利时利日利日大学生物医学和临床前科学系葡萄牙里斯本诺瓦德里斯本大学圣玛尔塔医院里斯本中心医院和诺瓦医学院法国斯特拉斯堡大学血管外科和肾移植系巴黎援助公社(AP-HP)CHU AmbroiseParé 法国布洛涅比兰科特巴黎萨克莱大学凡尔赛大学圣昆廷分校血管外科荷兰乌得勒支大学医学中心血管外科瑞典马尔默隆德大学斯科纳大学医院血管中心和马尔默临床科学英国布里斯托尔布里斯托尔大学塞尔维亚贝尔格莱德大学医学院塞尔维亚临床中心血管和血管内外科诊所丹麦欧登塞大学医院心胸血管外科意大利米兰大学临床与社区科学系米兰IRCCS CaGranda Ospedae Maggiore Policlinico基金会芬兰赫尔辛基赫尔辛基大学医院和赫尔辛基大学英国布里斯托尔北布里斯托尔NHS信托基金会布里斯托尔大学比利特根特大学医院瑞典乌普萨拉大学外科学系瑞典乌梅奥大学外科和围手术期科学系爱沙尼亚塔尔图塔尔图大学临床医学研究所外科学系美国纽约州石溪市石溪大学医学中心美国俄亥俄州托莱多普惠约布斯特血管研究所密歇根大学葡萄牙波尔图大学医学院英国伍斯特伍斯特郡皇家医院伍斯特郡急症医院NHS信托西班牙马德里La Luz Quiron Salud医院哥伦比亚波哥大安第斯大学圣菲基金会波兰卡托维兹西里西亚医科大学普通外科、血管外科、血管和静脉科新西兰达尼丁奥塔哥大学外科学系比利时Tielt圣安德列齐肯胡斯血管外科

2022年指南与2015年指南相比的新内容是什么?与2015年版《慢性静脉疾病(chronic venous disease,CVD)管理指南》1相比,该指南的总体结构做了很大修改,使其更加实用和方便。在不同章节中增加了关于管理策略的相关内容,并附有流程图。

关键词：临床实践指南血管外科学慢性静脉疾病管理指南流程图总体结构管理策略

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

熵增工程在电催化反应中的研究进展

引用

物理化学学报 2024年第7期40卷 36-42页

作者：张新义任楷刘妍宁谷振一黄志雄郑硕航王晓彤郭晋芝 igor V.Zatovsky 曹峻鸣吴兴隆东北师范大学化学学院长春130024 东北师范大学紫外光发光材料与技术教育部重点实验室长春130024 乌克兰国家科学院生物胶体化学研究所乌克兰基辅03142

目前对高性能与高稳定性的电催化剂进行精准合成仍然是亟待解决的问题。熵作为是最重要的热力学参数之一,是描述体系无序程度的物理量,其数值主要由材料的结构、磁矩、原子和电子振动共同决定。根据体系的构型熵值,我们通常将材料分为... 详细信息

目前对高性能与高稳定性的电催化剂进行精准合成仍然是亟待解决的问题。熵作为是最重要的热力学参数之一,是描述体系无序程度的物理量,其数值主要由材料的结构、磁矩、原子和电子振动共同决定。根据体系的构型熵值,我们通常将材料分为低熵材料(ΔS_(mix)1.5R)。随着熵值的增加,材料本征的物理与化学性质也会随之发生相应的变化。得益于不同金属元素的共存,在界面处原子级的多组分排列,所产生的协同性高熵效应能够有效地提升电催化反应的活性,因此在电催化领域中得到了广泛的研究关注。本综述对高熵电催化剂的基本概念、合成路线(“自上而下”与“自下而上”)以及在不同电催化反应类型中的高熵材料结构与性能之间的构效关系进行了系统总结,主要包括析氢(HER)、析氧(OER)、氧还原(ORR)、醇氧化(AOR)、氮还原(NRR)和二氧化碳还原反应(CO_(2)RR)等,从而阐明熵增工程对高性能电催化剂设计与应用的优势与潜力。同时,针对目前高熵催化剂研究所面临的主要问题与挑战,对未来基于熵增工程的高熵电催化剂的设计思路与合成方法进行展望。

关键词：熵增合成电化学高熵催化剂电催化

来源：

维普期刊数据库博看期刊

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Dynamic magnetic hysteresis in a liquid suspension of acicular maghemite particles

引用

Particuology 2009年第6期7卷 451-458页

作者： bronislav E.Kashevsky Sergey b.Kashevsky igor V.Prokhorov A.V.Luikov Heat and Mass Transfer Institute Belarus Academy of SciencesP.Brovka str.15Minsk 220072Belarus

This paper presents theoretical and experimental studies on the magnetodynamics and energy absorption in a dilute suspension of small ferromagnetic particles with magnetic hysteresis and mechanical mobility in an AC magnetic field. Experiments with 0.1% suspensions of acicular particles of gamma ferric oxide in solid and liquid matrices, subjected to a 430 Hz magnetic field with an intensity of up to 1200 Oe, revealed important role of particle mobility. The main qualitative and quantitative features of the phenomenon are in agreement with a model of joint magneto-mechanical dynamics of particles with a chain-of-spheres mode of incoherent magnetic reversal.

关键词： High-coercive magnetic particles Magnetic suspensions Dynamic magnetic hysteresis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Visible-light-induced synthesis of phosphorylated N-heterocycles through proton-coupled electron transfer

引用

Science China Chemistry 2021年第5期64卷 681-683页

作者： Vera A.Vil’ igor b.Krylov Alexander O.Terent’ev N.D.Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences Moscow 119991Russia

Phosphorus-containing organic compounds are important feedstock for the synthesis of value-added bioactive ***,the development of highly efficient synthetic methods for the construction of phosphorus-element bonds has drawn huge attention in the past decades[1].Particularly,the formation of P–C bonds from phosphoruscentered radicals has been demonstrated to be one of the most efficient and convenient strategies,which has been widely applied for the synthesis of organic phosphorus compounds in recent years.

关键词： synthesis bonds phosphorus

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Plasma-Assisted Chemistry in High-Speed Flow

引用

Plasma Science and Technology 2007年第6期9卷 760-765页

作者： Sergey b.LEONOV Dmitry A.YARANTSEV Anatoly P.NAPARTOVICH igor V.KOCHETOV Joint Institute for High Temperature Russian Academy of Science Izhorskaya str.13/19Moscow 125412Russia State

Fundamental problems related to the high-speed combustion are analyzed. The result of plasma-chemical modeling is presented as a motivation of experimental activity. Numerical simulations of the effect of uniform non-equilibrium discharge on the premixed hydrogen and ethylene-air mixture in supersonic flow demonstrate an advantage of such a technique over a heating. Experimental results on multi-electrode non-uniform discharge maintenance behind wallstep and in cavity of supersonic flow are presented. The model test on hydrogen and ethylene ignition is demonstrated at direct fuel injection to low-temperature high-speed airflow.

关键词： high-speed combustion electrical discharge nonequilibrium kinetics

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：