检索结果-南通市图书馆

A carbuncle cure for the harten-Lax-van Leer contact(hLLC)scheme using a novel velocity-based sensor

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2021年第9期42卷 1259-1278页

作者： u.S.VEVEK B.ZANG T.h.NEW Department of Mechanical Materials and Aerospace EngineeringUniversity of LiverpoolLiverpool L693BXUnited Kingdom Department of Aerospace Engineering University of BristolBristol BS81TRUnited Kindgdom School of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore

A hybrid numerical flux scheme is proposed by adapting the carbunclefree modified harten-Lax-van Leer contact(hLLCM) scheme to smoothly revert to the harten-Lax-van Leer contact(hLLC) scheme in regions of shear. This hybrid scheme, referred to as the hLLCT scheme, employs a novel, velocity-based shear sensor. In contrast to the non-local pressure-based shock sensors often used in carbuncle cures, the proposed shear sensor can be computed in a localized manner meaning that the hLLCT scheme can be easily introduced into existing codes without having to implement additional data structures. Through numerical experiments, it is shown that the hLLCT scheme is able to resolve shear layers accurately without succumbing to the shock instability.

关键词： carbuncle shock instability Euler equation numerical flux harten-Laxvan Leer contact(hLLC)scheme

The surface pollen and relative pollen production of the desert vegetation of the Alashan Plateau, western Inner Mongolia

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2003年第14期48卷 1488-1493页

作者： u.herzschuh h.Kuerschner MAYuzhen InstituteofPlantSystematicsandGeobotany FreeUniversityofBer-lin.Germanw DepartmentofGeography LanzhouUniversityLanzhou730000China

This preliminary investigation focuses on the comparison of the recent pollen precipitation and its related vegetation of eight different plant communities in the Alashan Region, the most western part of the Inner Mongolia Autonomous Region. Most zonal and azonal communities can be well identified by their pollen spectra. Relative pollen production factors of various plant taxa have been calculated and the following sequences from over- to under represented taxa have been found for zonal vegetation: Chenopodiaceae, Artemisia, Ephedra, Nitraria, Reaumuria, Calligonum, Zygophyllum; and for azonal vegetation: Peganum, Populus, Tamarix, Lycium.

关键词：内蒙古西部沙漠植被花粉植物分布植物群落地带性植被

Influence of Nitrogen Levels and Application Methods on Yield and Quality of Sorghum

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2008年第2期18卷 236-241页

作者： A.RAShID R.u.KhAN h.uLLAh Arid Zone Research Irstitute Department of Agronomy Faculty of Agriculture Gomal University

A field study was conducted for two years at the Arid Zone Research Institute, Dera Ismail Khan, Pakistan, to determine the optimum level of nitrogen and efficient application method in the production of sorghum （Sorghum bicolor L.）. using four levels of nitrogen, i.e., 0, 60, 90, and 120 kg ha^-1, and two different application methods （soil application and foliar spray）, the experiment was laid out in a split-plot design, where the main plots were used to determine the effective method of application and the subplots were used to detect the influence of N levels on the grain yield. The average data obtained after two years of study indicated an increase in the grain yields with an increase in N levels irrespective of the method used of N application. The grain yield increased from 2.92 to 5.61 t ha^-1 in the plots that were treated with 90 kg N ha^-1 compared with the control plots. Quadratic regression analysis showed that the increase in the yield was higher at the lower levels of N compared with the succeeding higher levels. The soil application method, producing an average grain yield of 4.79 t ha^-1, was found to be superior to the foliar spray method with an average grain yield of 4.56 t ha^-1. The protein content of the grain showed a linear increase with N application, attaining the maximum at 120 kg N ha^-1 in both the methods of N application. In addition, compared with the method of soil application, higher crude protein contents were observed using the method of foliar spray at all N levels.

关键词： foliar spray grain yield N level protein content soil application

hot Nuclear Matter Equation of State and Finite Temperature Kaon Condensation

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2008年第12期25卷 4233-4236页

作者：李昂左维 Schulze h. J. Lombardo u. Department of Physics and Institute of Theoretical Physics and Astrophysics Xiamen University Xiamen 361005 Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 INFN-LNS Via Santa Sofia 44 I-95123 Catania and Department of Physics and Astrophysics Catania University. Via Santa Sotia 64 I-95123 Italy

We perform a systematic calculation of the equation of state of asymmetric nuclear matter at finite temperature within the framework of the Brueckner-hartree-Fock approach with a microscopic three-body force. When applying it to the study of hot kaon condensed matter, we find that the thermal effect is more profound in comparison with normal matter, in particular around the threshold density. Also, the increase of temperature makes the equation of state slightly stiffer through suppression of kaon condensation.

关键词： field emission molybdenum dioxide enhancement factor

MnFe2O4@PANI@Ag heterogeneous Nanocatalyst for Degradation of Industrial Aqueous Organic Pollutants

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

Journal of Materials Science & Technology 2016年第2期32卷 134-141页

作者： Md.Amir u.Kurtan A.Baykal h.Sozeri Department of Chemistry Fatih UniversityCekmecelstanbul 34500 B.Turkey TuBITAK-uME National Merrology InstituteGebzeKocaeli 41470Turkey

This paper reports a stable heterogeneous nanoparticles catalyst MnFe2O4@PANI@Ag for the degradation of azo dyes. In this synthesizing method, MnFe204 is used as magnetic core and polyaniline （PANI） a linker to stabilize the Ag nanoparticles （NPs） on the surface of catalyst. The method has a high ability to prevent Ag NPs from aggregation on the PANI surface, thus resulting in small size and highly dispersed Ag NPs. The composition and nano-structural features of polycrystalline sample were studied by X-ray powder diffractometry, Fourier transform infrared spectroscopy, and scanning electron microsco- py. Vibrating sample magnetometer measurements proved the super-paramagnetic property of the catalyst, and uV results demonstrated that MnFe2O4@PANI@Ag has a high ability to reduce the azo dyes, which come from industrial wastes in the form of pollutant. The nanocomposites could be readily separated by magnet and reused for the next four reductions with high generation efficiency.

关键词： Ag NPs MnFe2O4 Magnetic nanocatalyst Catalytic degradation Azo dyes

Characterization of surface liquid segregation in SSM-hPDC aluminium alloys 7075,2024,6082 and A201

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2010年第S3期20卷 847-851页

作者： h.MLLER u.A.CuRLE E.P.MASuKu Materials Science and Manufacturing Council for Scientific and Industrial Research(CSIR)PretoriaSouth Africa

The surface liquid segregation(SLS) phenomenon in semi-solid metal-high pressure die casting(SSM-hPDC) plates of 7075,2024,6082 and A201 was investigated by different *** profiles were determined by firstly measuring the chemical composition of the surface of the plates using a Thermo Quantris optical emission spectrometer(OES).Material was then removed by a grinding process followed by measurement of the amount of material removed and chemical *** profiles of the main alloying elements were plotted for the cross-section of the plates in the as-cast and T6(after solution treatment) temper *** hardness profiles from the surface to the centre of the plates were *** samples of cross-sections of the castings were prepared and evaluated using a scanning electron *** results show that surface liquid segregation in SSM-hPDC alloys causes significant differences in properties between the surface and the bulk of these castings in both the F and T6 temper conditions.

关键词： semi-solid metal(SSM) forming alloy 7075 alloy 2024 alloy 6082 alloy A201 surface liquid segregation

在线全文

学校读者我要写书评

暂无评论

Cometary Physics

紫金山天文台台刊 1996年第2期15卷 26-39页

作者： h.u.Keller Max-Planck-Institut fur Aeronomie 37189 Katlenburg-Lindau Germany

unpredicted apparitions of bright comets appearing on the night sky for a few months movingfast among the stars have intrigued mankind whenever the sky was observed. Records ofcomets are found in the oldest documents and can be still useful as demonstrated during the as-sessment of the non-gravitational forces acting on comet halley(Yeomans and Kiang, 1981).chinese records with relatively precise positions from more than 2000 years ago gave

关键词： Cometary Physics than

The International Rosetta Mission

在线全文

学校读者我要写书评

暂无评论

紫金山天文台台刊 1996年第3期15卷 3-11页

作者： h.u.Keller max-Planck-Institut fur Aeronomie37189 Katlenburg-LindauGermany

The European Space Agency (ESA) launched its science programme horizon 2000 in themid *** programme encompasses four big missions, the cornerstones,in addition tosmaller missions. The four cornerstones are:SOhO/Cluster a solary observatory and in situmeasurements of the Earth magnetosphere,XMM and X-ray observatory,Rosetta a comet ren-dezvous mission,and FIRST a far infrared *** was successfully launched

关键词：卜甲加成入声

Self-Discovery anda Sense of Wholeness in the Transgressive Auto/biogrAfrical Discourses of African American Women Writers

在线全文

学校读者我要写书评

暂无评论

Fudan Journal of the humanities and Social Sciences 2022年第1期15卷 143-158页

作者： u.h.Ruhina Jesmin English Discipline Khulna UniversityKhulna 9208Bangladesh

The paper attempts to explore selected African American women writers'(Zora Neale hurston,Maya Angelou,Audre Lorde,and Alice Walker)self-discovery,celebration of their selfhood,and sense of wholeness in their auto/biogrAfrical *** rhetoricity of the autobiographers reflects politicization of black women's struggle,cultural(de)construction,and feminist/womanist(re)construction Instead of fitting into heteronormative discourses and aprocess of cultural assimilation,and of adhering to cultural codes of femininity,these writers transgress traditional norms of behavior Through autobiographical manifestos interwoven with self-defining identity and artistic transgression they powerfully assert notions of collective female agency and embrace their new-found identity as feminist *** an agent of awareness and proclamation,their(except hurston's)powerful rhetoric is infused with their triple consciousness of being a black woman with African background and cultural *** illustrate an interconnectedness of racism and sexism which causes double oppression on black *** boldly raise racial issues of universal significance,stick to their authentic selves,and reaffirm their agonizing black history/past as they journey toward maturity and *** discourses reflect an interweaving of past and present,individual and community,and personal and political changes which lead them toward an esthetic paradigmof wholeness.

关键词： Auto-biogrAfrican discourse Transgression Self-discovery Wholeness Female agency