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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.

关键词： hybrid nanofluid oscillating curved stretchable sheet gyrotactic microorganism Cattaneo-Christov heat and mass flux chemical reaction analytical solution O368

A　Possible　Origin　of　dark　Energy

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Chinese Physics Letters 2004年第6期21卷 1187-1188页

作者： t.d.Lee Physicsdepartment ColumbiaUniversityNewYorkNY10027USA

We discuss the possibility that the existence of dark energy may be due to the presence of a spin zero field φ(x), either elementary or composite. In the presence of other matter field, the transformation φ(x)→φ(x) + constant can generate a negative pressure, like the cosmological constant. In this picture, our universe can be thought as a very large bag, similar to the much smaller MIt bag model for a single nucleon.

关键词： Gravitation and cosmology Particle physics and field theory Astrophysics and astroparticles

the impact of alpha-fetoprotein (AFP), child-turcotte-pugh (CtP) score and disease staging on the survival of hepatocellular carcinoma (HCC) patients: a retrospective cohort from single oncology center

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Oncology research 2025年第1期33卷 149-160页

作者： Nasser Mulla Yousef Katib Asim M Almughamsi duaa S Alkhayat Mohamed Mosaad Samir t Alfotih Rawan Alaofi department of Internal Medicine Faculty of Medicine Taibah University Madinah 42278 Saudi Arabia. department of Radiology Faculty of Medicine Taibah University Madinah 42278 Saudi Arabia. department of Surgery Faculty of Medicine Taibah University Madinah 42278 Saudi Arabia. department of Endemic and Infectious diseases Suez Canal University Ismailia 41522 Egypt. King Salman bin Abdulaziz Medical City Madinah 42311 Saudi Arabia. Prince Mohammed Bin Abdulaziz Hospital Madinah 41511 Saudi Arabia.

Background:Hepatocellular carcinoma (HCC) is the most common cause of cancer-related death in Saudi Arabia. Our study aimed to investigate the patterns of HCC and the effect of tNM staging, Alfa-fetoprotein (AFP), and Child-turcotte Pugh (CtP) on patients' overall survival (OS).Methods:A retrospective analysis was conducted on 43 HCC patients at a single oncology center in Saudi Arabia from 2015 to 2020. All patients had to fulfill one of the following criteria: (a) a liver lesion reported as definitive HCC on dynamic imaging and/or (b) a biopsy-confirmed diagnosis.Results:the mean patient age of all HCC cases was 66.8 with a male-to-female ratio of 3.3:1. All patients were stratified into two groups: viral HCC (n = 22, 51%) and non-viral HCC (n = 21, 49%). Among viral-HCC patients, 55% were due to HBV and 45% due to HCV. Cirrhosis was diagnosed in 79% of cases. Age and sex did not significantly statistically differ in OS among viral and non-viral HCC patients (-value > 0.05). About 65% of patients had tumor size >5 cm during the diagnosis, with a significant statistical difference in OS (-value = 0.027). AFP was >400 ng/ml in 45% of the patients. there was a statistically significant difference in the OS in terms of AFP levels (-value = 0.021). A statistically significant difference was also observed between the CtP score and OS (-value = 0.02). CtP class B had the longest survival. BSC was the most common treatment provided to HCC patients followed by sorafenib therapy. there was a significant statistical difference in OS among viral and non-viral HCC patients (-value = 0.008).Conclusions:the most common predictors for OS were the underlying cause of HCC, AFP, and tumor size. Being having non-viral etiology, a tumor size >5 cm, an AFP > 400 ng/mL, and a CtP score class C were all negatively associated with OS.

关键词： Alpha-fetoprotein (AFP) Child-turcotte-pugh Hepatocellular carcinoma Pattern Progression free survival

Nonlinear thermo-mechanical stability of eccentrically stiffened functionally graded material sandwich doubly curved shallow shells with general sigmoid law and power law according to third-order shear deformation theory

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Applied Mathematics and Mechanics(English Edition) 2017年第2期38卷 191-216页

作者： d.V.dUNG d.t.dONG Faculty of Mathematics Mechanics and Informatics Vietnam National University Hanoi 100000 Vietnam Faculty of Civil Engineering University of Transport Technology Hanoi 100000 Vietnam

In this paper, the nonlinear analysis of stability of functionally graded ma- terial （FGM） sandwich doubly curved shallow shells is studied under thermo-mechanical loads with material properties obeying the general sigmoid law and power law of four ma- terial models. Shells are reinforced by the FGM stiffeners and rest on elastic foundations. theoretical formulations are derived by the third-order shear deformation theory （tSdt） with the von Karman-type nonlinearity taking into account the initial geometrical im- perfection and smeared stiffener technique. the explicit expressions for determining the critical buckling load and the post-buckling mechanical and thermal load-deflection curves are obtained by the Galerkin method. two iterative algorithms are presented. the effects of the stiffeners, the thermal element, the distribution law of material, the initial imper- fection, the foundation, and the geometrical parameters on buckling and post-buckling of shells are investigated.

关键词： functionally graded material (FGM) sandwich double curved shallow shell,thermo-mechanical stability FGM stiffener elastic foundation

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-tALOOKOLAEI H.GHANdVAR E.JUMAEV S.KHAtIR t.CUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for Engineering Application and technology Solutions Ho Chi Minh City Open University

this paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. the strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. the curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. the accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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Indium antimonide based HEMt for RF applications

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Journal of Semiconductors 2014年第11期35卷 20-22页

作者： t.d.Subash t.Gnanasekaran K.N.S.K College of Engineering Nagercoil-629901India RMK College of Engineering and technology Tamil Nadu601206India

We report on an indium antimonide high electron mobility transistor with record cut-off frequency characteristics. For high frequency response it is important to minimize parasitic resistance and capacitance to improve short-channel effects. For analog applications adequate pinch-off behavior is demonstrated. For proper device scaling we need high electron mobility and high electron density. toward this end, the device design features and simulation are carried out by the Synopsys tCAd tool. A 30 nm InSb HEMt exhibits an excellent cut-off frequency of 586 GHz. to the knowledge of the authors, the obtained cut-off frequency is the highest ever reported in any FEt on any material system.

关键词： HEMt InSb gate length cut-off frequency short-channel effects

Biodegradation of mixture of VOC's in a biofilter

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Journal of Environmental Sciences 2004年第1期16卷 30-33页

作者： d.Arulneyam t. Swaminathan Biotechnology Research Centre Department of Chemical EngineeringIndian Institute of TechnologyBiotechnology Research CentreDepartment of Chemical EngineeringIndian Institute of Technology Madras Chennai 600 036 IndiaMadras Chennai 600 036 India

Volatile organic compounds(VOC's) in air have become major concern in recent years. Biodegradation of a mixture of ethanol and methanol vapor was evaluated in a laboratory biofilter with a bed of compost and polystyrene particles using an acclimated mixed culture. the continuous performance of the biofilter was studied with different proportion of ethanol and methanol at different initial concentration and flow rates. the result showed significant removal for both ethanol and methanol, which were composition dependent. the presence of either compound in the mixture inhibited the biodegradation of the other.

关键词： biofilter methanol ethanol elimination capacity upset loading VOCs biodegradation

tuning the particle size,physical properties,and photocatalytic activity of Ag_(3)PO_(4)materials by changing the Ag^(+)/PO_(4)^(3-)ratio

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Chinese Physics B 2023年第3期32卷 561-568页

作者： Hung N M Oanh L t M Chung d P thang d V Mai V t Hang L t Minh N V Center for Nano Science and technology Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi 100000Vietnam department of Physics Hanoi National University of Education136 Xuan Thuy RoadCau Giay DistrictHanoi 100000Vietnam Hanoi University of Mining and Geology Duc Thang WardNorth Tu Liem DistrictHanoi 100000Vietnam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc VietHanoi 100000Vietnam Faculty of Basic Sciences Hanoi University of Natural Resources and Environment41 A Phu Dien RoadNorth Tu LiemHanoi 100000Vietnam

this study demonstrates the influence of the Ag^(+)/PO_(4)^(3-)ratio in precursor solution on the crystal structural formation,morphology,physical properties,and photocatalytic performance of a Ag_(3)PO_(4)photocatalyst that is fabricated,using a facile precipitation method,from AgNO_(3)and Na2HPO_(4)·12H_(2)*** material characterizations were carried out using x-ray diffraction(XRd),scanning electron microscopy(SEM),energy-dispersive x-ray spectroscopy(EdX),Brunauer–Emmett–teller(BEt)surface area,Fourier transform infrared(FtIR)absorption,Raman scattering,x-ray photoelectron spectroscopy(XPS),UV-vis absorption,and photoluminescence(PL).the results show that Ag_(3)PO_(4)crystallizes better when the excess PO_(4)^(3-)content increases,and the lattice parameters decrease slightly,while the crystal diameter and the particle size *** change is also observed in the Raman scattering and FtIR spectra with the increase in the vibration frequency of the[PO_(4)]*** compression of the[PO_(4)]unit was also confirmed in the XPS spectra with the shift of P 2p peaks toward higher binding *** photocatalytic results showed that the samples synthesized from excess PO_(4)^(3-)solution exhibited higher photocatalytic performance compared to the sample with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.A sample prepared from the precursor solution with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.5 was optimal for RhB decomposition under both visible light and natural sunlight,completely decomposing 10 ppm RhB after 15 minutes of xenon lamp irradiation and after 60 minutes under solar light *** is attributed to the high crystallinity,small particle size and low electron–hole recombination rate of the sample.

关键词： morphology photocatalytic Ag^(+)/PO_(4)^(3-)ratio visible light