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黄土高原黄土－古土壤的矿物组成及其环境意义

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地球化学 1994年第C期23卷 113-123页

作者：郑洪汉 b．k．g．theng J.S.Whitton 中国科学院广州地质新技术研究所，广州510640 DSIRLandResources LowerHuttNewZealand

采自洛川和西峰剖面的３４个黄土－古土壤样品分为砂、粉砂、粘土三个粒级进行了矿物成分分析。结果表明，黄土高原黄土和古土壤的矿物组成基本一致，除了方解石和褐铁矿、磁铁矿因在样品处理时已被剔除未予计算外，其主要矿物是石英、... 详细信息

采自洛川和西峰剖面的３４个黄土－古土壤样品分为砂、粉砂、粘土三个粒级进行了矿物成分分析。结果表明，黄土高原黄土和古土壤的矿物组成基本一致，除了方解石和褐铁矿、磁铁矿因在样品处理时已被剔除未予计算外，其主要矿物是石英、云母、长石和绿泥石。这４种矿物占总量的８８％－９１％，其他矿物有高岭石、蒙脱石、蛭石和少量重矿物。不同地质剖面和不同地层层位的矿物差异主要表现为组成矿物在含量和粒度上的变化。洛川与西峰剖面、古土壤与黄土以及相同古土壤层的上部与下部相比，它们的矿物组成主要表现为前者含有较少长石和较多云母和蛭石，而且颗粒较细，表明在土壤发育过程中使矿物转变的生物化学风化过程和使矿物颗粒由粗变细的物理风化过程并存。这一结果有利于这样一种土壤发育机制解释，即古土壤发育与黄土堆积过程同时进行，只是在古土壤发育时期黄土的堆积过程缓慢，成土作用大于黄土堆积作用而发育土壤。

关键词：黄土高原矿物组成环境意义黄土-古土壤成矿机制矿物变化

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粘土与聚合物的相互作用:总结与展望

地球与环境 1984年第1期 44-49页

作者： b.k.g.theng 林茂福

很久以来,土壤学家由于受土壤有机质(腐殖质)的生物稳定性的启发,对粘土与有机聚合物的相互作用发生了兴趣。腐殖质主要是一种黑色多阴离子的混合物。现在一般认为土壤里的粘土与腐殖质间的相互作用在许多土壤过程中(如矿物循环和风化,... 详细信息

很久以来,土壤学家由于受土壤有机质(腐殖质)的生物稳定性的启发,对粘土与有机聚合物的相互作用发生了兴趣。腐殖质主要是一种黑色多阴离子的混合物。现在一般认为土壤里的粘土与腐殖质间的相互作用在许多土壤过程中(如矿物循环和风化,剖面的发育及土壤团粒的稳定化)都起着重要的作用,而且往往起着决定性的作用。Jack(1963)指出,这种相互作用“……如同光合作用一样,对生命的存续是必不可少的,但与光合作用相比,却了解得很少”。这种说法并不过分。因为表层土壤几乎都是粘土或粘土矿物的有机复合体系,但一些荒漠和极地土壤可能例外。

关键词：聚合物大分子化合物粘土阳离子正离子钠蒙脱石吸附量粘土矿物粘粒矿物硅酸盐矿物吸附作用聚凝剂底面间距基面间距电荷阴离子基

Excellent photoluminescence and electrochemical properties of Sm^(3+) doped Ca_(2)MgSi_(2)O_(7) nanophosphor:Display and electrochemical sensor applications

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Journal of Rare Earths 2024年第6期42卷 1046-1055,I0002页

作者： R.b.basavaraj k.Sureshkumar D.P.Aarti M.b.Madhusudana Reddy g.Nagaraju T.Ramakrishnappa g.R.Navyashree k.R.Venkatesha babu k.S.Hemalatha Department of Physics BMS Institute of Technology and ManagementBangalore560064India Department of Chemistry BMS Institute of Technology and ManagementBangalore560064India Department of Chemistry School of Applied SciencesREVA UniversityBangalore560064India Energy Materials ResearchLaboratory Department of ChemistrySiddaganga Institute of TechnologyTumakuru57203KarnatakaIndia School of Physical Sciences REVA UniversityBangalore560057Indi Department of Physics Govt.Science CollegeBengaluru560001India Department of Physics Maharani Science College for WomenMaharani Cluster UniversityBengaluru560001India

A series of orange-red light emitting Ca_(2)MgSi_(2)O_(7):Sm^(3+)nanopowders were fabricated via low-cost ecofriendly green combustion technique using Aloe vera gel as *** phase purity of the samples were confirmed by the powder X-ray diffraction(PXRD)*** single-phase tetragonal structure is observed from the PXRD results with no additional impurity *** band gap energy of the fabricated powders was estimated by diffuse reflectance spectra(DRS)and is found to be in the range of 4.01-5.98 eV.A high resolution scanning electron microscope(SEM)was used to study the morphological behaviour of the ***-like structures are observed from the SEM *** particle size was evaluated by transmission electron microscopy(TEM)and is found to be~50 *** interplanar distance is found to be 0.53 *** properties were systematically studied in *** phosphors are successfully excited at 403 nm NUV light,producing reddish-orange characteristic *** emission peaks are centered at 558(^(4)g_(5/2)→^(6)H_(5/2)),607(^(4)g_(5/2)→^(6)H_(7/2))and 645 nm(^(4)g_(5/2)→^(6)H_(9/2)),*** the observed peaks the red emanation(^(4)g_(5/2)→^(6)H_(7/2))is stronger than the orange emission(^(4)g_(5/2)→^(6)H_(5/2))in the current *** photoluminescent concentration quenching is noticed above 5 mol%Sm^(3+)ion doping *** dipole-dipole interaction resulting in cross relaxation is found to be the principal cause of concentration quenching *** color features such as Commission Internationale de I’Eclairage(CIE)and correlated color temperature(CCT)were studied in *** optimized chromaticity coordinates were estimated to be(0.6363,0.3632),which fall in the reddish-orange *** average CCT value obtained is 3362 *** average color purity is found to be~82%.Sm^(3+)incorporated Ca_(2)MgSi_(2)O_(7) samples are possible contender for single white light generation commercial candidates owing to

关键词： green combustion Photoluminescence Orange-red emission Color purity Sensors Rare earths

Optimization of chemistry and process parameters for control of intermetallic formation in Mg sludges

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Journal of Magnesium and Alloys 2024年第4期12卷 1431-1448页

作者： Y.Fu g.g.Wang A.Hu Y.Li k.b.Thacker J.P.Weiler H.Hu Department of Mechanical Automotive and Materials EngineeringUniversity of Windsor401 Sunset AveWindsorOntario N9B 3P4Canada global Technology Centre Meridian Lightweight Technologies25 MacNab AveStrathroyOntario N7G 4H6Canada

Intermetallic formation in sludge during magnesium(Mg)melting,holding and high pressure die casting practices is a very important ***,very often it is overlooked by academia,original equipment manufacturers(OEM),metal ingot producers and even die *** aim of this study was to minimize the intermetallic formation in Mg sludge via the optimization of the chemistry and process *** Al8Mn5 intermetallic particles were identified by the microstructure analysis based on the Al and Mn *** design of experiment(DOE)technique,Taguchi method,was employed to minimize the intermetallic formation in the sludge of Mg alloys with various chemical compositions of Al,Mn,Fe,and different process parameters,holding temperature and holding *** sludge yield(SY)and intermetallic size(IS)was selected as two *** optimum combination of the levels in terms of minimizing the intermetallic formation were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,690℃ for the holding temperature and holding at 30 mins for the holding time,*** best combination for smallest intermetallic size were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,630℃ for the holding temperature and holding at 60 mins for the holding time,*** groups of sludge factors,Chemical Sludge(CSF),Physical Sludge(PSF)and Comprehensive Sludge Factors(and CPSF)were established for prediction of sludge yields and intermetallic sizes in Al-containing Mg *** CPSF with five independent variables including both chemical elements and process parameters gave high accuracy in prediction,as the prediction of the PSF with only the two processing parameters of the melt holding temperature and time showed a relatively large deviation from the experimental *** Chemical Sludge Factor was primarily designed for small ingot producers and die casters with a limited melting and holding capacity,of which process parameters could be fixed *** Physical Sludge Factor could be used f

关键词： Magnesium sludge Al-Mn intermetallic Optimization Taguchi method Sludge factor Chemical composition Process parameter

The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： k.D.küntz D.koutroumpa W.R.Dunn A.Foster F.S.Porter D.g.Sibeck b.Walsh The Henry A.Rowland Department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA goddard Space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATMOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance Department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

While we eagerly anticipate SMILE’s(Solar wind Magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission Mapper(LEM),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).With a field of view of~30′,LEM will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SMILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances

Assessing the biennial conference on science and technology(bICOST IX)2023 technical output on renewable energy,energy storage,and green hydrogen in line with UN SDg commitments

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Clean Energy 2024年第2期8卷 85-88页

作者： S.k.b.D.Silva k.g.D.Piyumali Rasitha Thilini Suranjana Perera k.D.k.g.kaluarachchi Thilini Munagamage R.M.R.Ahammed C.S.P.Piyankarage Seyed Shahmy Veranja karunaratne National Science and Technology Commission of Sri Lanka ColomboSri Lanka Sri Lanka Technological Campus(SLTC) PadukkaSri Lanka University of Peradeniya PeradeniyaSri Lanka

The development,production and utilization of renewable energy,energy storage and green hydrogen and the associated technologies in Sri Lanka have great potential to contribute to the United Nations’Sustainable Development goals(SDgs).The island aims to achieve 70%electricity generation from renewable energy sources by 2030(within the target of 40%utilization of renewable energy sources for the entire energy generation of the country by 2030).The power sector has to invest US$11 billion from 2023 to 2030 to contribute to reaching this *** commentary aims to provide a critical perspective on the recommendations of the report from the National Science and Technology Commission’s 9th biennial conference in 2023 on science and technology,the sub-thematic technical report on clean energy,energy storage and green hydrogen in line with the SDgs in the Sri Lankan *** technical report provides insightful recommendations for Sri Lanka’s energy sector under three main sections:renewable energy,energy storage and green ***,it explores the potential of various renewable energy sources,energy storage systems and green hydrogen as sustainable solutions to address the country’s energy challenges while emphasizing the spillover effects of them,which could contribute to the enterprise’s job creation and uplift the economy.

关键词： renewable energy energy storage green hydrogen sustainable development goals Sri Lanka social economic environmental sustainable affordable

Medication for birth Control in bitch at battambang City,battambang Province,Cambodia

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Journal of Environmental Science and Engineering(A) 2024年第2期13卷 61-67页

作者： Nal Si Sokun khoeurn Manay It kouch theng graduate School Royal University of AgriculturePhnom Penh 12400Cambodia Faculty of Agriculture University of Svay RiengSvay Rieng 200705Cambodia Faculty of Veterinary Medicine Royal University of AgriculturePhnom Penh 12400Cambodia

The observation study was conducted in battambang City,battambang province,by interviewing the 88 dog owners,who came to the animal pharmacy stores and clinics by using convenience sampling method of nonrandomized *** the results of the interviews,showed that the dog owners were selected in different range of age and gender,however,most of them were in middle age from 21-40 years old,with medium and rich living *** confinement in premise/house was primarily applied by dog *** number of bitches per household was from 1 to 3 batches,and there was no association with the wellbeing of the owners,and the age was from 2 to 4 years old,but some bitches had older *** of the bitches were dewormed in last 3 months and 6 months,however,there were some bitches last more than 6 months after *** bitch vaccination was applied by owner around for 60.00%.There were two popular types of vaccination,Rabies and DHLPP(Distemper,Hepatitis,Leptospirosis,Parvovirus,and Parainfluenza).For dog population management,about 94.29%of the owners apply nonsurgical method with applying *** reasons for using nonsurgical method were not only the cheapest price and easy way,but also there was no information on the consequence of using medication for birth *** medication was highly used before ***,almost half of them got health problem in less than 3 months after administration,also some got long-term *** clinical signs observed,the enlargement of belly was the most evidence,since 54.76%of affected bitches had shown it,then followed by discharge blood from vulvar,clear discharge and thick white pus from vulvar,accounting for 38.10%,35.71%and 26.71%,respectively.

关键词： bitch vaccination birth control clinical signs

Study of hybrid nanofluid flow in a stationary cone-disk system with temperature-dependent fluid properties

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 677-694页

作者： A.S.JOHN b.MAHANTHESH g.LORENZINI Center for Mathematical Needs Department of MathematicsCHRIST(Deemed to be University)Karnataka 560029India School of Mathematical and Statistical Sciences The University of Texas Rio Grande ValleyTexas 78539U.S.A. Department of Engineering and Architecture University of ParmaParma 43124Italy

Cone-disk systems find frequent use such as conical diffusers,medical devices,various rheometric,and viscosimetry *** this study,we investigate the three-dimensional flow of a water-based Ag-Mg O hybrid nanofluid in a static cone-disk system while considering temperature-dependent fluid *** the variable fluid properties affect the dynamics and heat transfer features is studied by Reynolds's linearized model for variable viscosity and Chiam's model for variable thermal *** single-phase nanofluid model is utilized to describe convective heat transfer in hybrid nanofluids,incorporating the experimental *** model is developed as a coupled system of convective-diffusion equations,encompassing the conservation of momentum and the conservation of thermal energy,in conjunction with an incompressibility condition.A self-similar model is developed by the Lie-group scaling transformations,and the subsequent self-similar equations are then solved *** influence of variable fluid parameters on both swirling and non-swirling flow cases is ***,the Nusselt number for the disk surface is *** is found that an increase in the temperature-dependent viscosity parameter enhances heat transfer characteristics in the static cone-disk system,while the thermal conductivity parameter has the opposite effect.

关键词： hybrid nanofluid cone-disk system laminar flow variable fluid property Nusselt number

Optimal Control of Service Rates of Discrete-Time(s,Q)Queueing-Inventory Systems with Finite buffer

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 261-280页

作者： L.Iniya b.Sivakumar g.Arivarignan School of Mathematics Madurai Kamaraj UniversityMaduraiTamilnaduIndia Department of Statistics Manonmaniam Sundaranar UniversityTirunelveliTamilnaduIndia

This article,we develop an optimal policy to control the service rate of a discrete time queueing-inventory system with finite *** customers arrive according to a bernoulli process and the service time for the customers are *** the buffer size attains its maximum,any arriving new customers are considered to be *** customers are served one by one according to FCFS rule and each customers request random number of *** inventory is replenished according to a(s,Q)inventory policy with geometric lead *** main objectives of this article are to determine the service rates to be employed at each slot so that the long run expected cost rate is minimized for fixed inventory level and fixed buffer size and to minimize the expected waiting time for a fixed inventory level and fixed buffer *** problems are modelled as Markov decision *** establish the existence of a stationary policy and employ linear programming method to find the optimal service *** provide some numerical examples to illustrate the behaviour of the model.

关键词： Queueing-inventory system discrete time batch demand-Markov decision process