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Science China Earth Sciences 2006年第9期49卷 915-925页

作者： J. Adam t.h. green GEMOC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia GEMOC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

Experiments were conducted on a natural basalt (with 5 wt.% added h2O) at 1.0―2.5 GPa and 900―1100℃. Experimental products include partial melts (quenched glasses) + residual mineral assemblages of amphibolite or eclogite. Electron microprobe and LAM-ICP-MS were used to determine major and trace element compositions of these quenched melts, respectively. Major ele- ment compositions of all the melts are tonalitic- trondhjemitic, similar to adakite. their trace element characteristics are controlled by coexisting residual minerals. Signatures of adakite such as high Sr/Y, low hREE and negative Nb-ta anomaly, etc. are present only in the melts coexisting with residual assemblages containing rutile and garnet (rutile-bearing eclogite or rutile-bearing amphibole-eclogite). Garnet leads to hREE depletion in melts, whereas rutile controls Nb and ta partitioning during the partial melting and causes negative Nb-ta anomaly in melts. therefore, in addition to garnet, rutile is also a necessary residual phase during the generation of adakite or ttG magmas to account for the negative Nb-ta anomaly of the magmas. the depth for the generation of adakite/ttG magmas via melting of metabasalt must be more than about 50 km based on the approximate 1.5 GPa mini- mum-pressure for rutile stability in the partial melting field of hydrous basalt.

关键词： trace element adakite/ttG magmas partial melting of metabasalt negativeNb-ta anomaly rutile

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-tALOOKOLAEI h.GhANDVAR E.JUMAEV S.KhAtIR t.CUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for Engineering Application and technology Solutions Ho Chi Minh City Open University

this paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. the strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. the curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. the accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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Preparation of plasma membrane of sperm cells of Zea mays and preliminary analysis of membrane protein

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Chinese Science Bulletin 1995年第13期40卷 1115-1119页

作者：张一洪杨中汉 t.h.曹宗巽 College of Life Science Peking University Beijing 100871 China

Just like in animals, the essence of fertilization process in plants is the fusion of male andfemale gametes. Although it is already possible, with the aid of cytological manipulation, toachieve in vitro fusion of isolated egg and sperm cell to form zygote, it remains to be solvedwhether the fusion of male and female gametes in nature is at random or there exists some kindof 'recognition'.

关键词： sucrose gradient ultracentrifugation organelle marker enzyme SDS-PAGE.

Interplay of S and As in Mekong Delta sediments during redox oscillations

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Geoscience Frontiers 2019年第5期10卷 1715-1729页

作者： Van t.h. Phan Fabrizio Bardelli Pierre Le Pape Raoul-Marie Couture Alejandro Fernandez-Martinez Delphine tisserand Rizlan Bernier-Latmani Laurent Charlet University Grenoble Alpes CNRSIRDIFSTTARISTerre38000GrenobleFrance ho Chi Minh City University of technology (hCMUt) Vietnam National UniversityHo Chi Minh City (VNU-HCM)268 Ly Thuong KietDistrict 10Ho Chi Minh CityViet Nam Institute of Nanotechnology (CNR-Nanotec) 00186RomeItaly Institut de Mineralogie de Physique des Materiaux et de Cosmochimie (IMPMC)UMR 7590 CNRS-UPMC-IRD-MNHN4 Place Jussieu75252Paris cedex 05France Département de chimie Université Laval1045 Avenue de la MédecineQuébecQCG1V 0A6Canada Ecole Polytechnique Fédérale de Lausanne (EPFL) e Environmental Microbiology Laboratory (EML) EPFL-ENAC-IIE-EMLStation 6CH-1015LausanneSwitzerland

the cumulative effects of periodic redox cycling on the mobility of As,Fe,and S from alluvial sediment to groundwater were investigated in bioreactor *** particular sediments from the alluvial floodplain of the Mekong Delta River were investigated: Matrix A (14 m deep) had a higher pyrite concentration than matrix B (7 m deep) *** present in matrix B but absent in matrix *** the reactors,the sediment suspensions were supplemented with As(III) and SO4^2-,and were subjected to three full-redox cycles entailing phases of nitrogen/CO2,compressed air sparging,and cellobiose *** differences in As concentration and speciation were observed upon redox *** support the fact that initial sediment composition is the main factor controlling arsenic release and its speciation during the redox ***,a high pyrite content associated with a low SO4^2- content resulted in an increase in dissolved As concentrations,mainly in the form of As(III),after anoxic half-cycles;whereas a decrease in As concentrations mainly in the form of As(V),was instead observed after oxic *** addition,oxic conditions were found to be responsible for pyrite and arsenian pyrite oxidation,increasing the As pool available for *** same processes seem to occur in sediment with the presence of gypsum,but,in this case,dissolved As were sequestered by biotic or abiotic redox reactions occurring in the FeeS system,and by specific physico-chemical condition (***).the contrasting results obtained for two sediments sampled from the same core show that many complexes and entangled factors are at work,and further refinement is needed to explain the spatial and temporal variability of As release to groundwater of the Mekong River Delta (Vietnam).

关键词： Redox oscillation Pyrite oxidation Gypsum dissolution Isotope sulfur Isotope oxygen

targeted yield concept and a framework of fertilizer recommendation in irrigated rice domains of subtropical India

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第12期7卷 963-968页

作者： BERA R. SEAL A. BhAttAChARYYA P. DAS t.h. SARKAR D. KANGJOO K. National Bureau of Soil Survey & Land Use Planning Indian Council of Agricultural Research Salt Lake Kolkata-700091 West Bengal India West Bengal State Council of Science & technology Bikash Bhawan Salt Lake Kolkata-700091 West Bengal India Brain Korea 21 Century Advanced Geo-Environmental Research Team School of Environmental Engineering Kunsan National University Kunsan Jeonbuk 573-701 South Korea Brain Korea 21 Century Advanced Geo-Environmental Research team School of Environmental Engineering Kunsan National University Kunsan Jeonbuk 573-701 South Korea

Soil test crop response （StCR） correlation studies were carried out in Vindhyan alluvial plain during 2001 to 2004 taking IR-36 as test crop to quantify rice production in the context of the variability of soil properties and use of balanced fertilizers based on targeted yield concept. the soils were developed on gently sloping alluvial plain with different physiographic settings and notable variation in drainage condition. Soil properties show moderate variation in texture （loamy to clay）, organic carbon content （4.4 to 9.8 g/kg）, cation exchange capacity （10,2 to 22.4 cmol （p＋）/kg） and ph （5.3 to 6,4）, Soil fertility status for N is low to medium （224 to 348 kg/ha）, P is medium to high （87 to 320 kg/ha） and K ranges from medium to high （158 to 678 kg/ha）. Database regarding nutrient requirement in kg/t of grain produce （NR）, the percent contribution from the soil available nutrients [CS （%）] and the percent contribution from the applied fertilizer nutrients [CF （%）] were computed for calibrating and fbrmulating fertilizer recommendations. Validity of the yield target for 7 and 8 t.h. was tested in farmers＇ fields and yields targets varied at less than 10%. the percent achievement of targets aimed at different level was more than 90%, indicating soil test based fertilizer recommendation approach was economically viable within the agro-ecological zone with relatively uniform cropping practices and socio-economic conditions.

关键词： Alluvial soil Nutrient requirements Yield target Paddy

CERIUM-INDUCED GRAIN BOUNDARY StRENGthENINGOF Ni_3Al ALLOYS

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Acta Metallurgica Sinica(English Letters) 1997年第4期10卷 349-357页

作者： Z.X. Yuan S.h. Song t.h. X.i X.J. Zhangand Z.S. Yu(Department of Material, Wuhan Ye in University of Science and technology, Wuhan 430081, China)(Department of Materials Physics, University of Science and technology Beijing, Beijing 100083, China) Wuhan Yejin Univ of Science and Technology Wuhan China

the infiuence of cerium on grnin boundaries of polycrpstalline N3Al alloys has beenstudied. the ja6mcability of a Ce-doped N3Al alloy strongly depends on the certumcontent. the alloy exhibits very poor fabrica6ility and cannot be fabrtcated into goodsheet8 by cold rolling when the concentmtion of cerium is t% or>0.044wt%.A 0.011wt%Ce-doped N3Al alloy exhibits relatively good fabricability and may be fab-ricated into useful sheets by repeated cold rolling with 1OOa C annealing. the ductilityof the alloy strongly depends on the cerium distribution. Wthout the grain boundaryprecipitation of a second phase containing cer1um) the higher the segmpation level ofcerzum, the 6ettcr the tensile properties of the alloys, and in turn the more enhancedthe grain boundary cohesion.

关键词： segregation Ni_3Al alloy ductility fabrication cerium

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AZ31镁合金搅拌摩擦点焊

焊接学报 2011年第3期32卷 101-104,118页

作者：尹玉环胡绳荪 North t.h. 张晓博孙娜天津大学材料科学与工程学院天津300072 天津市现代连接技术重点实验室天津300072 多伦多大学材料科学与工程学院多伦多N5S3E4 上海宝钢铸造有限公司上海201900 吉林大学教育部汽车材料重点实验室长春130025

研究了搅拌头旋转频率以及停留时间对AZ31镁合金搅拌摩擦点焊接头力学性能的影响.随着旋转频率的增大,不同搅拌针条件下,AZ31搅拌摩擦点焊接头的力学性能均呈现先增大后减小的趋势.随着停留时间的延长,AZ31搅拌摩擦点焊接头的力学性能... 详细信息

研究了搅拌头旋转频率以及停留时间对AZ31镁合金搅拌摩擦点焊接头力学性能的影响.随着旋转频率的增大,不同搅拌针条件下,AZ31搅拌摩擦点焊接头的力学性能均呈现先增大后减小的趋势.随着停留时间的延长,AZ31搅拌摩擦点焊接头的力学性能先增大随后在一定范围内波动.结果表明,结合宽度是影响搅拌摩擦点焊接头力学性能的重要因素,结合宽度越大,点焊接头的力学性能越好;此外,上下板之间界面特征对搅拌摩擦点焊接头的力学性能也具有重要的影响.

关键词：搅拌摩擦点焊力学性能旋转频率停留时间结合宽度

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残缺骑士

Physical and damping properties of kenaf fibre filled natural rubber/thermoplastic polyurethane composites

作者： (英)t.h.怀特

来源：南通市图书馆图书评论

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Defence technology（防务技术） 2020年第1期16卷 29-34页

作者： A.M.Noor Azammi S.M.Sapuan Mohamad R.Ishak Mohamed t.h.Sultan Advanced Engineering Materials and Composite Research Centre(AEMC) Department of Mechanical and Manufacturing EngineeringUniversity Putra Malaysia43400UPM SerdangSelangorMalaysia Automotive Engineering technology Section Universiti Kuala Lumpur Malaysian France Institute(UniKL-MFI)43650Bandar BaruBangiSelangorMalaysia Laboratory of Biocomposite technology Institute of Tropical Forestry and Forest Products(INTROP)Universiti Putra Malaysia43400UPM SerdangSelangorMalaysia Department of Aerospace Engineering Universiti Putra Malaysia43400UPM SerdangSelangorMalaysia

the paper presents the investigation of the effect of alkaline treatment of sodium hydroxide(NaOh) on physical and dynamic mechanical analysis(DMA) viscoelastic properties of kenaf fibre filled natural rubber(NR)/thermoplastic polyurethane(tPU) *** treated kenaf fiber,NR and tPU were weighed and proportioned according to the required compositions and were blended using hot mixed Brabender *** polymer composites were then fabricated using the hot press to form a sample *** sample was cut and prepared and water absorption,density,thickness swelling and DMA tests were *** far as physical properties are concerned,composites with the highest NR amount of shows the best results,which indicates good fiber bonding *** polymer composites with the highest amount of tPU shows the highest damping properties at.h.gh temperature.

关键词： Kenaf fiber Alkaline treatment thermoplastic polyurethane Natural rubber Dynamic mechanical analysis

Utilization of municipal solid waste incineration fly ash in lightweight aggregates

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Journal of Central South University 2012年第3期19卷 835-841页

作者：谭文发王里奥黄川刘元元 J.E.green D.Newport t.green State Key Laboratory for Coal Mine Disaster Dynamics and Control Resource and Environmental Science CollegeChongqing University Faculty of Urban Construction and Environmental Engineering Chongqing University Sustainability Research Institute University of East London RtAL(h.K.)Limited

Washing pre-treatrnent of municipal solid waste incineration （MSWI） fly ash blended with shale and sludge was utilized in the manufacture of light-weight aggregates and processed to form ceramic pellets. A formula uniform design was performed to arrange the mixture ratio of the materials. the optimal mixture ratio of the materials was determined by measuring the bulk density, granule strength, and 1 h water absorption of the pellets. It is shown that the optimal mixture ratios of materials, MSWI fly ash, shale, and sludge, are 23.16%, 62.58%, and 14.25% （mass fraction）, respectively. the performance testing indicators of light-weight aggregates are obtained under the optimum mixture ratio： bulk density of 613 kg/m3, granule strength of 821N, and 1 h water absorption of 11.6%, meeting 700 grade light-aggregate of GB/t 17431.2--1998 standard. the results suggest that utilization of MSWI fly ash in light-weight aggregates is an effective method and a potential means to create much more values.

关键词： MSWI fly ash pre-treatment trefoil rotary kiln heavy metal light-weight aggregates