检索结果-南通市图书馆

Magnetic reversal and magnetic memory effect in melt-spun Pr_2Fe_(14)b/α-Fe nanocomposite ribbons

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2015年第12期33卷 1303-1309页

作者：韩广兵苏浩高汝伟于淑云康仕寿朱明刚李卫 X.b.Liu School of Physics Shandong University Division of Functional Materials Central Iron & Steel Research Institute Department of Physics University of Texas at Arlington

The influence of CoCr addition on the microstructure and magnetic properties was investigated in nanocomposite Pr2Fel4b/a-Fe alloys prepared by melt spinning. It was shown that the magnetic properties of Pr2Fel4b/ct-Fe nanocomposite were im- proved by an addition of 10 at.% CoCr, in particular, coercivity （Hc） from 4.9 up to 5.3 kOe, maximum energy product （（bH）max） from 10.6 up to 13.9 MGOe, and remanence （Mr） from 94.2 up to 98.4 emu/g. The field dependencies of the reversible and irreversible magnetization components were derived from the recoil loops. Combining with the initial magnetization curves, the results indi- cated that the pinning of domain walls at the grain boundaries dominated the magnetization reversal in Pr2Fe14b/ct-Fe nanocomposite alloys. The magnetic memory effect was studied by measuring the magnetic moment relaxation at a cycle negative magnetic field with time interval of 600 s. The exchange-spring magnets with magnetic memory effect have a high potential for high density magnetic recording.

关键词： magnetization reversal exchange coupling magnetic memory effect nanocomposite alloys coercivity rare earths

Implementation of a choline bis(trifluoromethylsulfonyl)imide aqueous electrolyte for low temperature EDLCs enabled by a cosolvent

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2022年第7期31卷 84-94,I0004页

作者： Zhuanpei Wang Francois béguin Institute of Chemistry and Technical Electrochemistry Poznan University of TechnologyBerdychowo 460-965 PoznanPoland

We report a carbon/carbon capacitor based on micro/mesoporous carbon electrodes with cost-effective and eco-friendly aqueous choline bis(trifluoromethylsulfonyl)imide(Ch TFSI)electrolyte with a cosolvent enabling low-temperature operation down to-30℃.For this purpose,a Mg O-templated hierarchical carbon(MP98b)with an average mesopore diameter of 3.5 nm was prepared by pyrolysis of magnesium citrate hydrate at 900℃.To reach lower temperatures,the melting point and viscosity of the aqueous electrolyte were reduced by mixing water(W)with an organic solvent(methanol,M,or isopropanol,I)of high dielectric constant and low viscosity.5 mol kg^(-1)(5 m)Ch TFSI in an optimized volume fraction of cosolvent,M_(0.75)W_(0.25),and I_(0.75)W_(0.25),showed the highest conductivity;the higher conductivity in M_(0.75)W_(0.25)(22.8 and 3.1 m S cm^(-1) at 20 and-30℃,respectively)than in I_(0.75)W_(0.25)(8.5 and0.5 m S cm^(-1)at 20 and-30℃,respectively)is attributed to the lower viscosity of the M_(0.75)W_(0.25)*** electrochemical stability window(ESW)of 5 m Ch TFSI in M_(0.75)W_(0.25)and I_(0.75)W_(0.25)(1.6 V)on an MP98b electrode was determined by applying the ***,by adjusting the mass ratio of the two electrodes,a MP98b/MP98b capacitor using the 5 m electrolyte in M_(0.75)W_(0.25)could operate with a good life span up to 1.6 V while exhibiting a better charge propagation,greater specific capacitance,and higher specific energy than in I_(0.75)W_(0.25).

关键词： Carbon/carbon capacitor Choline bis(trifluoromethylsulfonyl)imide Low-temperature Aqueous electrolyte Cosolvent electrolyte Methanol Isopropanol

在线全文

学校读者我要写书评

暂无评论

迷宫之谜

Injection of N-Radicals into Diesel Engine Exhaust Treated by Plasma for Improved NO_x Removal: A Feasibility Study

作者： (英)亨利·艾略特(Henry eliot)

来源：南通市图书馆图书评论

学校读者我要写书评

暂无评论

Plasma Science and Technology 2006年第2期8卷 202-206页

作者： b. S. RAJANIKANTH b. R. SUSHMA Dept. of High Voltage Engineering Indian Institute of Science Bangalore 560012 India

Reported in this paper is a feasibility study on the injection of plasma induced N radicals for the abatement of NO and NOx present in the actual diesel exhaust. The radical laden diesel exhaust was further treated by discharge plasma in a dielectric barrier discharge reactor. N radicals were produced in a separate plasma reactor filled with baTiO3 pellets and were then injected into the treatment zone, There was a significant improvement in the efficiency when the radicals were injected compared to that when there was no radical injection. The efficiency of NOx removal at 0 load with plasma alone was 14% whereas with the injection of N radicals it went up to 38%, The results of the experiments conducted at different loads are discussed,

关键词： N-radical diesel engine exhaust NOx removal plasma treatment

bouncing scenario of general relativistic hydrodynamics in extended gravity

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2021年第2期73卷 96-101页

作者： A Y Shaikh b Mishra Department of Mathematics Indira Gandhi MahavidyalayaRalgaon-445402India Department of Mathematics Birla Institute of Technology and Science PilaniHyderabad CampusHyderabud-500078India

In this paper,we have framed bouncing cosmological model of the Universe in the presence of general relativistic hydrodynamics in an extended theory of *** metric assumed here is the flat Friedmann–Robertson–Walker space–time and the stress energy tensor is of perfect *** general relativity(GR)has certain issues with late time cosmic speed up phenomena,here we have introduced an additional matter geometry coupling that described the extended gravity to *** dynamical parameters are derived and *** dynamical behavior of the equation of state parameter has been *** have observed that the bouncing behavior is mostly controlled by the coupling parameter.

关键词： FRW metric extended gravity bouncing scenario energy conditions

Application of multi-criteria decision making methods for selection of micro-EDM process parameters

在线全文

学校读者我要写书评

暂无评论

Advances in Manufacturing 2014年第3期2卷 251-258页

作者： A.P.Tiwary b.b.Pradhan b.bhattacharyya Department of Mechanical Engineering Sikkim Manipal Institute of TechnologyEast Sikkim.Majitar 737136.India Department of Production Engineering Jadavpur UniversityKolkata 700032India

Ti-6A1-4V super alloy is an important engi- neering material with good strength to weight ratio and a wide range of applications in a number of engineering fields because of its excellent physical and mechanical properties. This work determines optimum process parameters such as pulse on time, peak current, gap voltage and flushing pressure, which influence the micro-electro discharge machining （EDM） process during machining of Ti-6AI-4V using combined methods of response surface methodology （RSM） and fuzzy-technique for order pref- erence by similarity to ideal solution （TOPSIS）. Central composite design （CCD） is used in the experimental investigation. A decision making model is developed to identify the optimum process parameters in the micro- EDM process, which influences several machining criteri- ons such as material removal rate （MRR）, tool wear rate （TWR）, overcut （OC） and taper. Triangular fuzzy numbers are used to determine the weighting factor for each process criterion. Further a fuzzy-TOPSIS method is used to select the most desirable factor level combinations. The proposed technique can be used to select optimal process parameters from various sets of combinations of process parameters in a micro-EDM process.

关键词： Micro-EDM - Ti-6A1-4V Fuzzy-techniquefor order preference by similarity to ideal solution(TOPSIS) Micromachining

Generalized Supersymmetric Perturbation Theory

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2004年第12期21卷 2330-2333页

作者： b.Goenül DepartmentofEngineeringPhysics UniversityofGaziantep27310GaziantepTurkey

Using the basic ingredient of supersymmetry, a simple alternative approach is developed to perturbation theory in one-dimensional non-relativistic quantum mechanics. The formulae for the energy shifts and wavefunctions do not involve tedious calculations which appear in the available perturbation theories. The model applicable in the same form to both the ground state and excited bound states, unlike the recently introduced supersymmetric perturbation technique which, together with other approaches based on logarithmic perturbation theory, are involved within the more general framework of the present formalism.

关键词： Perturbation techniques

Perturbative Quantum Chromodynamics α_(s)^(4)-Order Corrections to the Ratio R for τ Decay

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

Chinese Physics Letters 1998年第10期15卷 711-712页

作者： b.P.Nigam Department of Physics&Astronomy Box 871504Arizona State University TempeArizonaUSA 85287-1504

The perturbative quantum chromodynamics correction to the semihadronic decay rate R of the heavy leptonτwas expressed by braaten as an expansion in powers ofαs to orderα*** had found theα_(s)^(4)order correction to be significant and conjectured that theα_(s)^(4)order corrections might also be *** et *** corrected theα_(s)^(4)-order *** have extended the analytic calculations to orderαs4;it involves an unknown constant K3 which occurs inαs4 *** order to estimate the effect ofα_(s)^(4)order correction,we have chosen K3 to range from-1000 to+1000 and we find that the value of R changes by about-11%to+10%,respectively,compared to the value of R=3.5 obtained toα_(s)^(4)-order result.

关键词： correction α dynamics

Forced motion of an elastic filament through a narrow tube

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

Acta Mechanica Sinica 2015年第6期31卷 789-790页

作者： L.b.Freund Department of Materials Science and Engineering University of Illinois at Urbana Champaign

A polymer filament consisting of many similar molecules linked in a one-dimensional array is very flexible. As a result, shapes with a relatively large curvature can be accommodated elastically. When loosely confined in a thermal environment, such a flexible strand may become tangled owing to its flexibility. When confined within a narrow ＂tube＂ over its full length, a flexible molecule may behave quite differently. Here, we consider the qualitative nature of deformation of an individual filament when confined within a tube. Commonly the tube is formed within the cluster by a large number of surrounding filaments of the same type.

关键词： Statistical mechanics. biofilament. Reptation Partition function