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Model with strong γ_4 t-violation

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Chinese Physics C 2008年第12期32卷 939-944页

作者： r. Friedberg t. D. Lee Physics Department Columbia University New York NY 10027 U.S.A. China Center of Advanced Science and technology (CCASt/World Lab.) P.O. Box 8730

eAbstract We extend the t violating model of the paper on ＂Hidden symmetry of the CKM and neutrinomapping matrices＂ by assuming its t-violating phases X↑ and X↓ to be large and the same, with X = X↑ = X↓. In this case, the model has 9 real parameters： at, α↑,β↑,ξ↑,η↑t for the t-quark sector, α↓,β↓,ξ↓,η↓, for the sector and a common X- We examine whether these nine parameters are compatible with ten observables： the six quark masses and the four real parameters that characterize the CKM matrix （i.e., the Jarlskog invariant and three Eulerian angles）. We find that this is possible only if the t violating phase X is large, between -120^o to -135^o. In this strong t violating model, the smallness of theJarlskog invariant 3 × 10^-5 ismainly accounted for by the large heavy quark masses, with mc/mt〈ms/mb≈0.02, as well as the near completeoverlap of t and b quark, with （c｜b）=-0.04.

关键词： Jarlskog invariant CKM matrix strong γ4 t-violation

transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 177-192页

作者： M.NAVEED M.IMrAN t.ASGHAr Z.ABBAS Department of Mathematics Division of Science and TechnologyUniversity of Education Department of Mathematics The Islamia University of Bahawalpur

this paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. the influence of magnetic fields is also inspected in terms of their physical characteristics. to depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAM).the effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

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Characterization of mixing in an optimized designed t–t mixer with cylindrical elements

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Chinese Journal of Chemical Engineering 2019年第10期27卷 2337-2351页

作者： t.Manoj Dundi V.r.K.raju V.P.Chandramohan Mechanical Engineering Department National Institute of TechnologyWarangalTelangana StateIndia

Passive micromixers are preferred over active mixers for many microfluidic applications due to their relative ease in integration into complex systems and operational *** also incur very low cost of ***,the degree of mixing is comparatively low in passive mixers than active mixers due to the absence of disturbance in the flow by external forces and the inherent laminar nature of microchannel *** designs of complex channel structures and three-dimensional geometries have been investigated in the past to obtain an efficient mixing in passive *** the studies on mixing enhancement with simple planar geometries of passive mixers have been few and *** present work aims to investigate the possibility of mixing enhancement by employing simple planar type designs,such as t-mixer and t–t mixer with cylindrical elements placed in the mixing *** mixing performance has been evaluated in the reynolds number range of 6 *** results have shown that t–t mixer with cylindrical elements performed significantly well and obtained very good mixing quality over basic t-mixer for the entire range of reynolds number(6 to 700).the device has also shown better mixing as compared to basic t–t mixer and t-mixer with cylindrical elements.A larger pair of vortices formed in the stagnation area due to the presence of a cylindrical element in the *** elements downstream caused significant enhancement in mixing due to splitting and recombining *** size of the cylindrical element in the t–t mixer has been optimized to obtain better mixing performance of the *** improvement in mixing quality by t–t mixer with cylindrical elements has been obtained at the expense of small rise in pressure drop as compared to other passive designs considered in this ***,the current design of t–t mixer with cylindrical elements can act as an effective and simple passive mixing device for various mi

关键词： CFD-simulation Cylindrical elements Micromixers Mixing quality Obstructions t–t-mixer

Water and nutrient recovery from urine:A lead up trail using nano-structured In_(2)S_(3)photo electrodes

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Chinese Physics B 2021年第5期30卷 531-535页

作者： r Jayakrishnan t r Sreerev Adith Varma Department of Physics University of KeralaThiruvananthapuramKerala 695581India Photovoltaic research Laboratory Christian College Chenagnnur 689122India

Developments of economic systems are critical for bio-regenerative life support systems in manned space *** this work we report on the feasibility of using two direct sunlight powered processes sequentially for the recovery of water and nutrients from *** work presents experimental evidence on nutrient and water recovery achieved using the proto-type designed and *** report the design and testing of a solar still which would serve on the nutrient recovery *** cooled condensate from the solar still is fed into a solar powered electrolysis unit where nano-structured indium sulphide(In_(2)S_(3))thin films coated over fluorine doped tin oxide(SnO_(2):F)substrate serve as one of the working *** electrolysis takes place in the absence of an electrolyte which manifests as a technical achievement of our *** results show that the COD level in the recycled water is very *** In_(2)S_(3)photo-electrodes are stable without any physical damage after the process.

关键词： semiconductors water quality thin film structure and morphology electrolysis

Management of pests and diseases of tropical sericultural plants by using plant-derived products: a review

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Journal of Forestry research 2015年第3期26卷 533-544页

作者： r.t.Gahukar Arag Biotech Pvt. Ltd. Plot 220 Reshimbag NagpurMaharashtra 440009 India

Host plants of domesticated silkworms in tropical countries are attacked by an array of insect pests, disease pathogens and nematodes. In order to reduce resulting plant damage, chemicals have been extensively used. In recent years, products extracted/isolated from 47 plant species have been tested as replacements for or to minimize the use of hazardous chemicals. Bioefficacy of the extract in water or chemical solvent, crude seed/leaf oil, and cake is discussed, and integrated management of major and occasional pests and plant diseases is proposed in sericultural plants in order to produce chemical-free foliage.

关键词： Commercial pesticides Integratedmanagement Plant extracts Pests and diseasesSericultural plants

Control of seismic and operational vibrations of rotating machines using semi-active mounts

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Earthquake Engineering and Engineering Vibration 2004年第1期3卷 85-100页

作者： r.rana t.t.Soong Ove Arup & partners Department of Civil Structural.and Environmental EngineeringState University of New York

A dual isolation problem for rotating machines consists of isolation of housing structures from the machine vibrations and protection of machines during an earthquake to maintain their functionality. Desirable characteristics of machine mounts for the above two purposes can differ significantly due to difference in nature of the excitation and performance criteria in the two situations. In this paper, relevant response quantities are identified that may be used to quantify performance and simplified models of rotating machines are presented using which these relevant response quantities may be calculated. Using random vibration approach with a stationary excitation, it is shown that significant improvement in seismic performance is achievable by proper mount design. results of shaking table experiments performed with a realistic setup using a centrifugal pump are presented. It is concluded that a solution to this dual isolation problem lies in a semi-active mount capable switching its properties from ‘operation-optimum’ to ‘seismic-optimum’ at the onset of a seismic event.

关键词： rotating machines simple modeling seismic control operational control semi-active control

Electro-optical properties and(E,F) phase diagram of fluorinated chiral smectic liquid crystals

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Chinese Physics B 2018年第10期27卷 570-577页

作者： r Zgueb H Dhaouadi t Othman Universite tunis El-Manar Faculte des Sciences de Tunis Laboratoire de physique de la matiere molle et de modelisation electromagnetique (LP3ME) Campus Universitaire Farhat Hached 2092 Tunis Tunisie

Fluorinated smectic liquid crystals each with a biphenyl benzoate rigid core are investigated. Molecular structures of the studied compounds have difference only in fluorine position and the length of the carbon chain. Dielectric relaxation study and electro-optical measurements are carried out with the classical SSFLC geometry. the field-induced phase transitions are studied and the（E,t） phase diagram is established.

关键词： smectic liquid crystal dielectric relaxation electro-optical properties phase transition (E,t)phase diagram

Saint-Venant torsion analysis of bars with rectangular cross-section and effective coating layers

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Applied Mathematics and Mechanics(English Edition) 2016年第2期37卷 237-252页

作者： H.tEIMOOrI r.t.FAAL r.DAS Department of Mathematics and Computer Science Allameh Tabatabai University Faculty of Engineering University of Zanjan Department of Mechanical Engineering and Centre for Advanced Composite Materials University of Auckland

this paper investigates the torsion analysis of coated bars with a rectangular cross-section. two opposite faces of a bar are coated by two isotropie layers with different materials of the original substrate that are perfectly bonded to the bar. With the Saint- Venant torsion theory, the governing equation of the problem in terms of the warping function is established and solved using the finite Fourier cosine transform. the state of stress on the cross-section, warping of the cross-section, and torsional rigidity of the bar are evaluated. Effects of thickness of the coating layers and material properties on these quantities are investigated. A set of graphs are provided that can be used to determine the coating thicknesses and material properties so as to keep the maximum von Mises stress on the cross-section below an allowable value for effective use of the coating layer.

关键词： Saint-Venant torsion rectangular cross-section coating layer torsional rigidity

Exact solutions to drift-flux multiphase flow models through Lie group symmetry analysis

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Applied Mathematics and Mechanics(English Edition) 2015年第8期36卷 1105-1112页

作者： B.BIrA t.r.SEKHAr Department of Mathematics National Institute of Science and Technology Department of Mathematics Indian Institute of Technology Kharagpur

In the present paper, Lie group symmetry method is used to obtain some exact solutions for a hyperbolic system of partial differential equations （PDEs）, which governs an isothermal no-slip drift-flux model for multiphase flow problem. those sym- metries are used for the governing system of equations to obtain infinitesimal transforma- tions, which consequently reduces the governing system of PDEs to a system of ODEs. Further, the solutions of the system of ODEs which in turn produces some exact solutions for the PDEs are presented. Finally, the evolutionary behavior of weak discontinuity is discussed.

关键词： multiphase flow drift-flux models Lie group analysis exact solution weakdiscontinuity