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Band head spin determination of triaxial superdeformed bands in ^163,164,165Lu through two-parameter formulae

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Chinese Physics C 2018年第11期42卷 72-77页

作者： honey Sharma h.m. mittal Dr. B.R. Ambedkar National Institute of Technology Jalandhar 144011 India

The two-parameter formulae, i.e. the nuclear softness formula and the power index formula, have been used to obtain the band head spin （I0） of the triaxial superdeformed （SD） bands in ^163Lu（1,2,3,4）, ^164Lu（1,2,3） and ^165Lu（1,2,3）, in the A - 160 mass region. The least squares fitting approach is used. The values of the root mean square （RmS） deviation among the computed and the measured experimental transition energies are obtained by calculating the model parameters. Whenever accurate spins are available, superb agreement is shown between the determined and the measured experimental transition energies. In comparison to the power index formula, the values of band head spin （I0） of the triaxial SD bands in ^163Lu（1,2,3,4）, ^164Lu（1,2,3） and ^165Lu（1,2,3） obtained by the nuclear softness formula are closer to the experimental data. The lowest RmS deviation is also achieved by the nuclear softness formula. hence, the nuclear softness formula works well for obtaining the band head spin （I0） for the triaxial SD bands in ^163Lu（1,2,3,4）, ^164Lu（1,2,3） and ^165Lu（1,2,3） in the A-160 mass region. The dynamic moment of inertia against hω is also studied.

关键词： band head spin nuclear softness formula power index formula triaxial superdeformed bands

An empirical study on vortex-generator insert fitted in tubular heat exchangers with dilute Cu–water nanofluid flow

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Chinese Journal of Chemical Engineering 2016年第6期24卷 728-736页

作者： m. Khoshvaght-Aliabadi m.h. Akbari F. hormozi Department of Chemical Engineering Shahrood Branch Islamic Azad University Shahrood lran School of Chemical Petroleum and Gas Engineering Semnan University Semnan lran

The heat transfer enhancement(hTE) in tubular heat exchangers fitted with vortex-generator(VG) inserts is experimentally investigated. The studied four parameters and ranges are: winglets-pitch ratio(1.33, 2.67, and 4),winglets-length ratio(0.33, 0.67, and 1), winglets-width ratio(0.2, 0.4, and 0.6), and Reynolds number(5200to 12200). The testing fluids are the water and Cu–water nanofluid at the volumetric fraction of 0.2%. The results obtained on hTE, pressure drop, and performance evaluation criterion(PEC) are compared with those for water in a smooth tube. It is found that the VG inserts with lower winglets-pitch ratio and higher winglets-length/width ratios present higher values of hTE and pressure drop. Over the range studied, the maximum PEC of 1.83 is detected with the Cu–water nanofluid inside the tube equipped with a VG insert at the winglets-width ratio of0.6 for the maximum Reynolds number, when the heat transfer rate and pressure drop are 1.24 times and 2.03 times of those in the smooth tube. Generalized regression equations of the Nusselt number, friction factor, and PEC are presented for the tubular heat exchangers with the VG inserts for both water and Cu–water *** is concluded that the main advantage of the VG inserts is their simple fabrication and considerable performance, particularly at higher Reynolds number.

关键词： heat transfer enhancementVortex-generator insertNanofluid Turbulent flowCorrelation

Band head spin assignment of superdeformed bands in 86Zr

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Chinese Physics C 2016年第11期40卷 88-94页

作者： Anshul Dadwal h.m.mittal Ambedkar National Institute of Technology Jalandhar 144011India

Two parameter expressions for rotational spectra viz. variable moment of inertia （VmI）, ab formula and three parameter harris w2 expansion are used to assign the band head spins （I0） of four rotational superdeformed bands in 86Zr. The least-squares fitting method is employed to obtain the band head spins of these four bands in the A - 80 mass region. model parameters are extracted by fitting of intraband y-ray energies, so as to obtain a minimum root-mean-square （rms） deviation between the calculated and the observed transition energies. The calculated transition energies are found to depend sensitively on the assigned spins. Whenever an accurate band head spin is assigned, the calculated transition energies axe in agreement with the experimental transition energies. The dynamic moment of inertia is also extracted and its variation with rotational frequency is investigated. Since a better agreement of band head spin with experimental results is found using the VmI model, it is a more powerful tool than the ab formula and harris w2 expansion.

关键词： Superdeformed bands VmI model ab formula harris w2 expansion

A Note on the Browder's and Weyl's Theorem

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Acta mathematica Sinica,English Series 2008年第12期24卷 2015-2020页

作者： m.AmOUCh h.ZGUITTI Department of mathematics Faculty of Science Semlalia B.O. 2390 Marrakesh Morocco Department of mathematics Faculty of Science of Rabat B. O. 1014 Rabat Morocco

Let T be a Banach space operator, E（T） be the set of all isolated eigenvalues of T and π（T） be the set of all poles of T. In this work, we show that Browder＇s theorem for T is equivalent to the localized single-valued extension property at all complex numbers λ in the complement of the Weyl spectrum of T, and we give some characterization of Weyl＇s theorem for operator satisfying E（T） = π（T）. An application is also given.

关键词： Weyl's theorem generalized Weyl's theorem Browder's theorem generalized Browder'stheorem single-valued extension property

RELAXATION OF FUNCTIONALS INVOLVING hOmOGENEOUS FUNCTIONS AND INVARIANCE OF ENVELOPES

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Chinese Annals of mathematics,Series B 2002年第1期23卷 37-52页

作者： m.BOUSSELSAL h.LEDRET Departmentofmathematics EcoleNormaleSupérieureB.P.92VieuxKouba16050AlgiersAlgeria Laboratoired’AnalyaeNumérique UniversitéPierreetMarieCurieBoitecourrier18775252ParisCedex05France

The authors compute the quasiconvex envelope of certain functions defined on the space m,.mn of real m x n matrices via a homogeneous function on mmn - They also deduce Invariance properties for various convex envelopes from corresponding invariance properties satisfied by a function. Some applications related in particular to nonlinear elasticity arc given.

关键词： homogeneous functions Quasiconvex envelope Nonlinear elasticity

Numerical methods for solving singular integral equations obtained by fracture mechanical analysis of cracked wedge

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Applied mathematics and mechanics(English Edition) 2014年第3期35卷 311-324页

作者： m.GhADIRI h.GhASEmI Faculty of Engineering and Technology Department of Mechanical EngineeringImam Khomeini International University

The numerical solutions to the singular integral equations obtained by the fracture mechanical analyses of a cracked wedge under three different conditions are considered. The three considered conditions are:(i) a radial crack on a wedge with a nonfinite radius under the traction-traction boundary condition,(ii) a radial crack on a wedge with a finite radius under the traction-traction boundary condition, and(iii) a radial crack on a finite radius wedge under the traction-displacement boundary condition. According to the boundary conditions, the extracted singular integral equations have different forms. Numerical methods are used to solve the obtained coupled singular integral equations, where the Gauss-Legendre and the Gauss-Chebyshev polynomials are used to approximate the responses of the singular integral equations. The results are presented in figures and compared with those obtained by the analytical response. The results show that the obtained Gauss-Chebyshev polynomial response is closer to the analytical response.

关键词： fracture mechanics numerical analytical singular integral equation Gauss-Legendre

molecular and carbon isotopic compositions of gas inclusions of deep carbonate rocks in the Tarim Basin

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Science China Earth Sciences 2004年第5期47卷 445-452页

作者： paul Farrimond Fossil Fuels and Environmental Geochemistry Drummond Building University of Newcastle upon Tyne Newcastle upon Tyne NE17RU UK

Gaseous components of gas inclusions in deep carbonate rocks (>5700 m) from the Tacan 1 well were analyzed by online mass spectrometry by means of either the stepwise heat-ing technique or vacuum electromagnetism crushing. The carbon isotopic compositions of gases released by vacuum electromagnetism crushing were also measured. Although the molecular compositions of gas inclusions show differences between the two methods, the overall charac-teristics are that gas inclusions mainly contain CO2, whilst hydrocarbon gases, such as Ch4, C2h6 and C3h8, are less abundant. The content of CO is higher in the stepwise heating experi-ment than that in the method of vacuum electromagnetism crushing, and there are only minor amounts of N2, h2 and O2 in gas inclusions. methane d 13C values of gas inclusions in Lower Ordovician and Upper Cambrian rocks (from 5713.7 to 6422 m; -52—63) are similar to those of bacterial methane, but their chemical compositions do not exhibit the dry character in comparison with biogenic gases. These characteristics of deep gas inclusions may be related to the migration fractionation. Some deep natural gases with light carbon isotopic characteristics in the Tazhong Uplift may have a similar origin. The d 13C1 values of gas inclusions in Lower Cam-brian rocks (7117—7124 m) are heavier (-39), consistent with highly mature natural gases. Carbon isotopic compositions of CO2 in the gas inclusions of deep carbonate rocks are similar (from -4 to 13) to those of deep natural gases, indicating predominantly an inorganic origin.

关键词： Tarim Basin, deep carbonate rock, gas inclusion component, carbon isotope.

Systematic dependence of SFE＊B(E2)↑ and ROTE＊B(E2)↑on N_pN_n in the framework of shape fluctuation model

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Chinese Physics C 2017年第5期41卷 116-121页

作者： Amit Bindra h.m.mittal Department of Physics Dr.B.R.Ambedkar National Institute of Technology

A systematic dependence of shape fluctuation energy product SFE ＊ B（E2）↑ and rotational energy product ROTE ＊ B（E2）↑ on the valence nucleon product Np Nn is carried out in the Z = 50-82,N = 82-126 major shell *** the shape transitional nuclei,the product SFE＊B（E2）↑ drops to zero and becomes negative,indicating direct dependence on N_pN_n.A relative rise,on the other hand,is observed in the product ROTE＊B（E2） ↑plotted against N_pN_n for all the nuclei in Z = 50-82 and N = *** the N 〉 104 region,large positive values of the product SFE ＊ B（E2） ↑ are observed for the Pt nucleus,which indicates sphericity.A systematic study of the product SFE ＊ B（E2）↑ and ROTE ＊ B（E2） ↑ with atomic number Z is also *** products SFE ＊ B（E2） ↑and ROTE ＊ B（E2） ↑ vary sharply with Z for the N = 88 *** discuss here for the first time the correlation between SFE ＊ B（E2） ↑ and ROTE ＊ B（E2） ↑ with valence nucleon product N_pN_n.

关键词： fluctuation nuclei E2 and ROTE*B nucleus rotational valence deformed transitional sharply

Band head spin assignment of superdeformed bands in hg isotopes through power index formula

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Chinese Physics C 2018年第5期42卷 79-84页

作者： honey Sharma h.m.mittal Dr.B.R.Ambedkar National Institute of Technology Jalandhar144011India

The power index formula has been used to obtain the band head spin(I0) of all the superdeformed(SD) bands in hg isotopes. A least squares fitting approach is used. The root mean square deviations between the determined and the observed transition energies are calculated by extracting the model parameters using the power index formula. Whenever definite spins are available, the determined and the observed transition energies are in accordance with each other. The computed values of dynamic moment of inertia J~((2)) obtained by using the power index formula and its deviation with the rotational frequency is also studied. Excellent agreement is shown between the calculated and the experimental results for J~((2)) versus the rotational frequency. hence, the power index formula works very well for all the SD bands in hg isotopes expect for195hg(2, 3, 4).

关键词： superdeformed bands power index formula