检索结果-南通市图书馆

microstructure and mechanical Properties of Dissimilar Double-side Friction stir Welds Between medium-Thick 6061-T6 Aluminum and Pure Copper Plates

在线全文

学校读者我要写书评

暂无评论

Acta metallurgica sinica(English letters) 2022年第12期35卷 2027-2046页

作者： J.X.Tang l.shi C.s.Wu m.X.Wu s.Gao mOE Key lab for liquid-solid structure Evolution and materials Processing Institute of Materials JoiningShandong UniversityJinan 250061China state Grid Henan Electric Power Research Institute Zhengzhou 450052China school of mechanical Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China

It is difficult to achieve Al/Cu dissimilar welds with good mechanical properties for medium-thick plates due to the inherent high heat generation rate at the shoulder-workpiece contact interface in conventional friction stir ***,doubleside friction stir welding is innovatively applied to join 12-mm medium-thick 6061-T6 aluminum alloy and pure copper dissimilar plates,and the effect of welding speeds on the joint microstructure and mechanical properties of Al/Cu welds is systematically *** reveals that a sound Al/Cu joint without macroscopic defects can be achieved when the welding speed is lower than 180 mm/min,while a nonuniform relatively thick intermetallic compound(ImC)layer is formed at the Al/Cu interface,resulting in lots of local microcracks within the first-pass weld under the plunging force of the tool during friction stir welding of the second-pass,and seriously deteriorates the mechanical properties of the *** the increase of welding speed to more than 300 mm/min void defects appear in the joint,but the joint properties are still better than the welds performed at low welding speed conditions since a continuous uniform thin ImCs layer is formed at the Al/Cu *** maximum tensile strength and elongation of Al/Cu weld are,respectively,135.11 mPa and 6.06%,which is achieved at the welding speed of 400 mm/*** addition,due to the influence of welding distortion of the first-pass weld,the secondpass weld is more prone to form void defects than the first-pass weld when the same plunge depth is applied on both *** double-side friction stir welding is proved to be a good method for dissimilar welding of medium-thick Al/Cu plates.

关键词： Double-side friction stir welding medium-thick plate Dissimilar welding microstructures Intermetallic compounds mechanical properties

Petrogenesis of carbonatitic lamproitic dykes from sidhi gneissic complex,Central India

在线全文

学校读者我要写书评

暂无评论

Geoscience Frontiers 2018年第2期9卷 531-547页

作者： m.satyanarayanan D.V.subba Rao m.l.Renjith s.P.singh E.V.s.s.K.Babu m.m.Korakoppa CsIR-National Geophysical Research Institute Hyderabad 500007India Geological survey of India Hyderabad 500068India Department of Geology Bundelkhand UniversityJhansi 284128India NCEGR Geological Survey of IndiaBengaluru 560070India

Petrographic, mineral chemical and whole-rock geochemical characteristics of two newly discovered lamproitic dykes(Dyke 1 and Dyke 2) from the sidhi Gneissic Complex(sGC), Central India are presented here. Both these dykes have almost similar sequence of mineral-textural patterns indicative of:(1) an early cumulate forming event in a deeper magma chamber where megacrystic/large size phenocrysts of phlogopites have crystallized along with subordinate amount of olivine and clinopyroxene;(2) crystallization at shallow crustal levels promoted fine-grained phlogopite, K-feldspar, calcite and Fe-Ti oxides in the groundmass;(3) dyke emplacement related quench texture(plumose K-feldspar, acicular phlogopites) and finally(4) post emplacement autometasomatism by hydrothermal fluids which percolated as micro-veins and altered the mafic phases. Phlogopite phenocrysts often display resorption textures together with growth zoning indicating that during their crystallization equilibrium at the crystal-melt interface fluctuated multiple times probably due to incremental addition or chaotic dynamic self mixing of the lamproitic magma. Carbonate aggregates as late stage melt segregation are common in both these dykes, however their micro-xenolithic forms suggest that assimilation with a plutonic carbonatite body also played a key role in enhancing the carbonatitic nature of these dykes. Geochemically both dykes are ultrapotassic(K_2 O/Na_2 O: 3.0-9.4) with low CaO, Al_2 O_3 and Na_2 O content and high siO_2(53.3-55.6 wt.%)and K_2 O/Al_2 O_3 ratio(0.51-0.89) characterizing them as high-silica lamproites. Inspite of these similarities, many other features indicate that both these dykes have evolved independently from two distinct magmas. In dyke 1, phlogopite composition has evolved towards the minette trend(Al-enrichment) from a differentiated parental magma having low mgO, Ni and Cr content; whereas in dyke 2, phlogopite composition shows an evolutionary affinity towards the lamproit

关键词： lamproite Phlogopite Carbonate aggregates metasomatized mantle sidhi Gneissic Complex Central India

Dewetting in associating lattice gas model confined by hydrophobic walls

在线全文

学校读者我要写书评

暂无评论

science China(Physics,mechanics & Astronomy) 2019年第10期62卷 60-67页

作者： Tassylla OFonseca marcia m.szortyka Patricia Temes Cristina Gavazzoni Alan Bde oliveira marcia CBarbosa Instituto de Fsica Universidade Federal do Rio Grande do SulPorto Alegre 91501-970Brasil Universidade Federal de santa Catarina Rua Pedro Joao PereiraMato Alto 88900-000Brasil Instituto Federal Catarinense Sao Bento do Sul 89283-064Brasil Instituto de Quimica Universidade Estadual de CampinasCampinas 13083-970Brasil Departamento de Fisica Universidade Federal de Ouro PretoOuro Preto 35400-000Brasil

The phase behavior of a two dimensional fluid confined within hydrophobic walls is obtained by monte Carlo *** fluid is described by the associating lattice gas model which reproduces the density and diffusion anomalous behavior of *** confined fluid exhibits a liquid-liquid critical temperature which decreases with the decrease of the distance between the confining *** contact with the wall a dewetting is *** thickness of this interfacial layer is independent of the distance between the two *** for very small distances between the two walls no total depletion is observed and consequently no drying transition is present.

关键词： water lattice confined

A Novel Fusion system Based on Iris and Ear Biometrics for E-exams

在线全文

学校读者我要写书评

暂无评论

Intelligent Automation & soft Computing 2023年第3期35卷 3295-3315页

作者： s.A.shaban Hosnia m.m.Ahmed D.l.Elsheweikh Department of Computer science Faculty of Specific EducationMansoura UniversityEgypt

With the rapid spread of the coronavirus epidemic all over the world,educational and other institutions are heading towards *** the era of digitization,identifying educational e-platform users using ear and iris based multi-modal biometric systems constitutes an urgent and interesting research topic to pre-serve enterprise security,particularly with wearing a face mask as a precaution against the new coronavirus *** study proposes a multimodal system based on ear and iris biometrics at the feature fusion level to identify students in electronic examinations(E-exams)during the COVID-19 *** proposed system comprises four ***ﬁrst step is image preprocessing,which includes enhancing,segmenting,and extracting the regions of *** second step is feature extraction,where the Haralick texture and shape methods are used to extract the features of ear images,whereas Tamura texture and color histogram methods are used to extract the features of iris *** third step is feature fusion,where the extracted features of the ear and iris images are combined into one sequential fused *** fourth step is the matching,which is executed using the City Block Dis-tance(CTB)for student identiﬁ***ﬁndings of the study indicate that the system’s recognition accuracy is 97%,with a 2%False Acceptance Rate(FAR),a 4%False Rejection Rate(FRR),a 94%Correct Recognition Rate(CRR),and a 96%Genuine Acceptance Rate(GAR).In addition,the proposed recognition sys-tem achieved higher accuracy than other related systems.

关键词： City block distance(CTB) Covid-19 ear biometric e-exams feature-level fusion iris biometric multimodal biometric student’s identity

Hardware,software,and Wetware Codesign Environment for synthetic Biology

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

BioDesign Research 2022年第1期2022卷 136-150页

作者： samuel m.D.oliveira Douglas Densmore Department of Electrical and Computer Engineering Boston UniversityMA 02215USA Biological Design Center Boston UniversityMA 02215USA

synthetic biology is the process of forward engineering living *** systems can be used to produce biobased materials,agriculture,medicine,and *** approach to designing these systems is to employ techniques from the design of embedded *** techniques include abstraction,standards,modularity,automated design,and formal semantic models of ***,these elements form the foundation of“biodesign automation,”where software,robotics,and microfluidic devices combine to create exciting biological systems of the *** paper describes a“hardware,software,wetware”codesign vision where software tools can be made to act as“genetic compilers”that transform high-level specifications into engineered“genetic circuits”(wetware).This is followed by a process where automation equipment,welldefined experimental workflows,and microfluidic devices are explicitly designed to house,execute,and test these circuits(hardware).These systems can be used as either massively parallel experimental platforms or distributed bioremediation and biosensing ***,scheduling and control algorithms(software)manage these systems’actual execution and data analysis tasks.A distinguishing feature of this approach is how all three of these aspects(hardware,software,and wetware)may be derived from the same basic specification in parallel and generated to fulfill specific cost,performance,and structural requirements.

关键词： hardware Together execution

Apoptosis induced by a low-carbohydrate and high-protein diet in rat livers

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

World Journal of Gastroenterology 2016年第22期22卷 5165-5172页

作者： maria Emília l monteiro Analucia R Xavier Felipe l oliveira Porphirio Js Filho Vilma B Azeredo Department of Internal medicine Medicine College Fluminense Federal University Niteroi RJ 24030-210 Brazil Department of Pathology Medicine College Fluminense Federal University Niteroi RJ 24030-210 Brazil Biomedical science Institute Federal University of Rio de Janeiro Rio de Janeiro RJ 21941-913 Brazil Department of Nutrition and Dietitian Nutrition College Fluminense Federal University Niteroi RJ 24030-210 Brazil

AIm: To determine whether high-protein, high-fat, and low-carbohydrate diets can cause lesions in rat ***: We randomly divided 20 female Wistar rats into a control diet group and an experimental diet group. Animals in the control group received an AIN-93 m diet, and animals in the experimental group received an Atkins-based diet(59.46% protein, 31.77% fat, and 8.77% carbohydrate). After 8 wk, the rats were anesthetized and exsanguinated for transaminases analysis, and their livers were removed for flow cytometry, immunohistochemistry, and light microscopy studies. We expressed the data as mean ± standard deviation(sd) assuming unpaired and parametric data; we analyzed differences using the student's t-test. statistical significance was set at P lasma alanine aminotransferase and aspartate aminotransferase levels were significantly higher in the experimental group than in the control group. According to flow cytometry, the percentages of nonviable cells were 11.67% ± 1.12% for early apoptosis, 12.07% ± 1.11% for late apoptosis, and 7.11% ± 0.44% for non-apoptotic death in the experimental diet group and 3.73% ± 0.50% for early apoptosis, 5.67% ± 0.72% for late apoptosis, and 3.82% ± 0.28% for non-apoptotic death in the control diet group. The mean percentage of early apoptosis was higher in the experimental diet group than in the control diet group. Immunohistochemistry for autophagy was negative in both groups. sinusoidal dilation around the central vein and small hepatocytes was only observed in the experimental diet group, and fibrosis was not identified by hematoxylin-eosin or Trichrome masson staining in either ***: Eight weeks of an experimental diet resulted in cellular and histopathological lesions in rat livers. Apoptosis was our principal finding; elevated plasma transaminases demonstrate hepatic lesions.

关键词： Apoptosis liver injury High-protein diet High-fat diet low-carbohydrate diet

Computational algorithms to simulate the steel continuous casting

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

International Journal of minerals,metallurgy and materials 2010年第5期17卷 596-607页

作者： A. Ramírez-lópez G. soto-Cortés m. Palomar-Pardavé m.A. Romero-Romo R. Aguilar-lópez Institute Polytechnic National(mexico) Department of materials Metropolitan Autonomous University

Computational simulation is a very powerful tool to analyze industrial processes to reduce operating risks and improve profits from equipment. The present work describes the development of some computational algorithms based on the numerical method to create a simulator for the continuous casting process, which is the most popular method to produce steel products for metallurgical industries. The kinematics of industrial processing was computationally reproduced using subroutines logically programmed. The cast steel by each strand was calculated using an iterative method nested in the main loop. The process was repeated at each time step （？t） to calculate the casting time, simultaneously, the steel billets produced were counted and stored. The subroutines were used for creating a computational representation of a continuous casting plant （CCP） and displaying the simulation of the steel displacement through the CCP. These algorithms have been developed to create a simulator using the programming language C＋＋. Algorithms for computer animation of the continuous casting process were created using a graphical user interface （GUI）. Finally, the simulator functionality was shown and validated by comparing with the industrial information of the steel production of three casters.

关键词： continuous casting simulation numerical method computational algorithm

material Research Related to structural Pavement Failure on motorway A32 in the Netherlands

在线全文

学校读者我要写书评

暂无评论

武汉理工大学学报 2010年第17期32卷 8-17页

作者： HOUBEN l J m mOlENAAR A A A ERKENs s m J G Faculty Civil Engineering and Geosciences Delft University of Technology ministry of Traffic Public Works and Water ManagementCentre for Transport and Navigation

In 2008 structural failures occurred on the asphalt pavement,with a hydraulic blast furnace slag base,of the motorway A32 (constructed in 1986～1988) in the Netherlands. Within a few weeks serious depressions occurred,in which the asphalt pavement was full of cracks and the base had a very low stiffness. In 2008 and 2009 the pavement including the base was rehabilitated over a length of 10 *** Dutch ministry of Public Works has initiated an extensive research into the risks of occurrence of this type of unexpected structural damages on the main road network in the Netherlands. Among many other things this research includes material research into the base material of the A32 to find the cause of the structural *** total 130 cores,divided over 26 cross-sections,were drilled from the A32. The cross-sections were divided over 3 areas,with a high and low base stiffness respectively and also at heaves that had grown into the pavement since 1998. In areas with high base stiffness the cores mainly contained bound base material,in areas with low base stiffness mainly granular material and at the heaves it was a mix thereof. standard (static) and dynamic crushing tests were done on the granular material. Dynamic and monotonic indirect tensile tests and compression tests were performed on the bound material. In all cases no systematic difference was found between the mechanical properties of the blast furnace slag base material from the heavily loaded right traffic lane and the material from the other *** is concluded that the pavement failure on the A32 is introduced by the occurrence of full depth asphalt fatigue cracks in the pavement that was originally designed for 12 years (but was never strengthened) in areas where the base stiffness always has been low or became low through crushing (that also has resulted in the heaves). Penetrated rainwater then has weakened the base and pumping has occurred,resulting into loss of bearing capacity and decrease of vo

关键词： structural failure blast furnace slags base laboratory testing

Biological protection of plants in agricultular landscape—state of the art, problems and ways of their decision

在线全文

学校读者我要写书评

暂无评论

浙江大学学报（农业与生命科学版） 2004年第4期30卷 398-400页

作者： sokolov m s Kolombet l V Research Center for Toxicology and Hygienic Regulation of Biopreparations State Research Center for Applied Microbiology 142279 Obolensk Moscow Region Russia 142253 Serpukhov Moscow reg. Russia

Biological protection of plants: definition and objectives. Technologically, biological protection of plants (hereinafter bioprotection) is a high agricultural technology involving agricultural landscape approach and basee on an ecological imperative, namely “use living beings against living beings”. In a wide sense, present-day bioprotection is a fundamental and applied field of knowledge providing harmless suppression of harmful agents during cultivation and storage of agricultural crops by use natural and (or) artificially constructed organisms (including genetically modified ones having pesticidal properties) and products of their live cycle. The overall objective of bioprotection consists in producing harmless, profitable and high-quality vegetative raw material, food, fodder. At the same time, bioprotection agrotechnologies are important environment forming and environment maintaining factors, steady and positively influencing the health of both rural ethnos, and agrosphere as a whole. Realization of integrated bioprotection approaches should provide minimum destruction of beneficial and non-target organisms, excluding the succession of harmful species and appearance of species resistant to biocontrol agents. 2. Theoretical foundation of bioprotection. The following postulates and imperatives of biosphere science, agrarian and social ecology make the scientific basis of bioprotection: “The Nature knows the how and why of things better”; steady, balanced development of agrosphere (proceeding from a presumption of life support) is based on biocentrism and biosystem relations, or consortism of its consorbents; Control of the agrosphere by human beings could be effective only in case of primary realization of biocenotic regulation; Biocenotic regulation, dynamics of the number and species diversity of agrosphere is realized through trophically similar cenoconsorcia and tritrophic systems, that provides maintenance and preservation of trophically proved critica

关键词：植物生物保护农业景观农业气候设施园艺