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Spatial distribution of δ2H and δ18O values in the hydrologic cycle of the Nile basin

Journal of Arid Land 2015年第2期7卷 133-145页

作者： Jeff b LANGMAN School of Science and Engineering American University in Cairo Department of Geological Sciences University of Idaho

Existing δ2H and δ18O values for precipitation and surface water in the Nile basin were used to analyze precipitation inputs and the influence of evaporation on the isotopic signal of the Nile River and its tributaries. The goal of the data analysis was to better understand basin processes that influence seasonal streamflow for the source waters of the Nile River, because climate and hydrologic models have continued to produce high uncertainty in the prediction of precipitation and streamflow in the Nile basin. An evaluation of differences in precipitation δ2H and δ18O values through linear regression and distribution analysis indicate variation by region and season in the isotopic signal of precipitation across the Nile basin. The White Nile basin receives precipitation with a more depleted isotopic signal compared to the blue Nile basin. The hot temperatures of the Sahelian spring produce a greater evaporation signal in the precipitation isotope distribution compared to precipitation in the Sahara/Mediterranean region, which can be influenced by storms moving in from the Mediterranean Sea. The larger evaporative effect is reversed for the two regions in summer because of the cooling of the Sahel from inflow of Indian Ocean monsoon moisture that predominantly influences the climate of the blue Nile basin. The regional precipitation isotopic signals convey to each region＇s streamflow, which is further modified by additional evaporation according to the local climate. Isotope ratios for White Nile streamflow are significantly altered by evaporation in the Sudd, but this isotopic signal is minimized for streamflow in the Nile River during the winter, spring and summer seasons because of the flow dominance of the blue Nile. During fall, the contribution from the White Nile may exceed that of the blue Nile, and the heavier isotopic signal of the White Nile becomes apparent. The variation in climatic conditions of the Nile River basin provides a means of identifying mech

关键词： Nile River arid environment deuterium excess regional climate model uncertainty evaporation isotope effects

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ON A CLASS OF KTHE SEQUENCE SPACES WITH NORMAL STRUCTURE

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Acta Mathematica Scientia 2011年第2期31卷 576-590页

作者： b. Zlatanov Department of Mathematics and Informatics Plovdiv University

In this note, we investigate the generalized modulus of convexity δ（λ） and the generalized modulus smoothness p（λ）. We obtain some estimates of these moduli for X=lp. We obtain inequalities between WCS coefficient of a KSthe sequence space X and δX（λ）. We show that, for a wide class of class the sequence spaces X, if for some ε∈（0, 9/10] holds δx（e）〉 1/3（1- √3/2）ε, then X has normal structure.

关键词： Weakly convergent sequence coefficient modulus of convexity generalizedmodulus of convexity normal structure

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From geometry to non-geometry via T-duality

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Chinese Physics C 2018年第8期42卷 65-87页

作者： b.Sazdovi Institute of Physics University of Belgrade

Reconsideration of the T-duality of the open string allows us to introduce some geometric features in non-geometric ***,we have found what symmetry is T-dual to the local gauge *** includes transformations of background fields but does not include transformations of the *** to this we have introduced a new,up to now missing term,with additional gauge field Ai^D（D denotes components with Dirichlet boundary conditions）.It compensates non-fulfilment of the invariance under such transformations on the end-points of an open string,and the standard gauge field AaN（N denotes components with Neumann boundary conditions）compensates non-fulfilment of the gauge *** a generalized procedure we will perform T-duality of vector fields linear in *** show that gauge fields AaNand AiDare T-dual to ADaand AN^*** introduce the field strength of T-dual non-geometric theories as derivatives of T-dual gauge fields along both T-dual variable yμand its double？yμ.This definition allows us to obtain gauge transformation of non-geometric theories which leaves the T-dual field strength ***,we introduce some new features of non-geometric theories where field strength has both antisymmetric and symmetric *** allows us to define new kinds of truly non-geometric theories.

关键词： T-duality non-geometry open string neumann boundary conditions dirichlet boundary conditions

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

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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

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

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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

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bouncing scenario of general relativistic hydrodynamics in extended gravity

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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–Rob.rtson–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

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

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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

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Generalized Supersymmetric Perturbation Theory

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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

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

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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

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Forced motion of an elastic filament through a narrow tube

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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

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