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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.s.ience 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

Complement:a global immunometabolic regulator in amyotrophic lateral sclerosis

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Neural Regeneration Research 2021年第6期16卷 1210-1211页

作者： Martin W.Lo John d.lee school of Biomedical sciences Faculty of MedicineThe University of QueenslandSt LuciaQueenslandAustralia

Recently,Mcdonald et al.(2020)proposed that complement causes a metabolic switch to lipid consumption in amyotrophic lateral sclerosis(ALs),which raises the possibility of complement as a global immunometabolic *** ALs,neuromuscular degeneration occurs concurrently with complement-mediated inflammation,glucose intolerance,and elevated lipid ***,complement is being increasingly recognized as a metabolic regulator that can induce insulin resistance and alter fuel source ***,the authors propose that chronic complement activation may be driving metabolic reprogramming in ALs,which has broad implications for the field of immunometabolism and would be the first mechanistic explanation of the“lipid.s.itch”in ***,it suggests that complement can drive a global shift in resources during inflammation,in which glucose is redirected from peripheral tissues to immune cells to support their inflammatory actions.

关键词： inflammation metabolism elevated

Nanoscale resistive switching devices for memory and computing applications

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Nano Research 2020年第5期13卷 1228-1243页

作者： seung Hwan lee Xiaojian Zhu Wei d.Lu department of Electrical Engineering and Computer science The University of MichiganAnn ArborMichigan 48109USA

With the slowing down of the Moore’s law and fundamental limitations due to the von-Neumann bottleneck,continued improvements in computing hardware performance become increasingly more *** switching(Rs)devices are being extensively studied as promising candidates for next generation memory and computing applications due to their fast switching speed,excellent endurance and retention,and.s.aling and three-dimensional(3d.s.acking *** particular,Rs devices offer the potential to natively emulate the functions and.s.ructures of synapses and neurons,allowing them to efficiently implement neural networks(NNs)and other in-memory computing systems for data intensive applications such as machine learning *** this review,we will examine the mechanisms of Rs effects and d.s.uss recent progresses in the application of Rs devices for memory,deep learning accelerator,and more faithful brain-inspired computing *** and possible solutions at the device,algorithm,and.s.stem levels will also be d.s.ussed.

关键词： resistive switching oxygen vacancy metal cation memory application in-memory computing bio-inspired application

EFFECT OF CARBON ANd BORON ON MICROsTRUCTURE ANd MECHANICAL PROPERTIEs OF A sINGLE CRYsTAL sUPERALLOY RR 2072

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Acta Metallurgica sinica(English Letters) 2005年第1期18卷 33-38页

作者： d.H.Kim d.H.Ye J.H.lee Y.s.Yoo C.Y.Jo High Temperature Materials Laboratory Korea Institute of Machinery&Materials 66 SangnamChangwonKyungnam 640-010S.Korea dept.of Metallurgy Changwon National Univerisity 9 SarimChagwonKyungnam 640-773S.Korea

Carbon and boron have been considered to strengthen grain boundaries that might form during single crystal *** this study the effect of boron on solidification behavior and creep properties of the carbon doped.s.ngle crystal RR 2072 has been *** order to understand.s.lidification behavior with boron addition,the solid/liquid interface morphology and.s.lidification microstructure were examined with solidification *** relationship between mi-crostructural evolution and creep properties of the carbon and boron modified.s.ngle crystal has been also investigated.

关键词： single crystal superalloy defect tolerance directional solidification creep rupture

A study of the Critical Nozzle for Flow Rate Measurement of High-Pressure Hydrogen Gas

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Journal of Thermal science 2007年第1期16卷 28-32页

作者： H.d.Kim J.H.lee K.A.Park T.setoguchi s.Matsuo school of Mechanical Engineering Andong National University388Songchun-dongAndong 760-749Korea dynamics Group Korea Research Institute of Standards and SciencePO Box 102YusongTaejon 305-606Korea department of Mechanical Enginering.saga University 1Honjo—machiSaga-shiSaga 840—8502Japan

The mass flow rate measurement using a critical nozzle shows the validity of the inviscid theory, indicating that the d.s.harge coefficient increases and approaches unity as the Reynolds number increases under the ideal gas law However, when the critical nozzle measures the mass flow rate of a real gas such as hydrogen at a pressure of hundreds bar, the d.s.harge coefficient exceeds unity, and the real gas effects should be taken into account. The present study aims at investigating the flow features of the critical nozzle using high-pressured hydrogen gas. The axisymmetric, compressible Navier-stokes computation is employed to simulate the critical nozzle flow, and a fully implicit finite volume method is used to d.s.retize the governing equation system. The real gas effects are simulated to consider the intermolecular forces, which account for the possibility of liquefying hydrogen gas. The computational results are compared with past experimental data. It has been found that the coefficient of d.s.harge for real gas can be corrected properly below unity adopting the real gas assumption.

关键词： critical nozzle compressible flow hydrogen gas ideal gas law real gas effect

FATIGUE LIVEs FOR INdUCTION HARdENEd.s.AFTs MATERIALs ACCORdING TO THE ENVIRONMENTAL TEMPERATUREs

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Acta Metallurgica sinica(English Letters) 2005年第5期18卷 585-593页

作者： d.G. lee K.C. Jang J.M. Kuk I.s. Kim Korea Institute of Ind.s.rial Technology Gwangju 506-824 Korea dept. of Mechanical Engineering Mokpo National University Mokpo 534-729 Korea

Rotary bending fatigue tests were carried out with two kinds of materials, s43C and.s.0C, using the front engine and front drive shaft （FF shaft） of vehicle. The specimens were induction hardened about 1.0mm depth from the specimen surface, and the hardness value on the surface was about HRC56-60. The tested environment temperatures were -30, 25 and 80℃ in order to look over effect of the induction hardening and the environmental temperatures on the fatigue characteristics. The fatigue limit of induction hardened.s.ecimens increased more about 45% than non-hardened.s.ecimens showing that the endurances of s43C and.s.0C were 98.1 and 107.9MPa in non-hardened.s.mples, 147.1 and 156.9MPa in hardened.s.mplesrespectably. The maximum tensile and compressive stress on the small circular defect was about ＋250 and -450MPa respectively when circular defect is situated on top and bottom. The fatigue life increased 80, 25 and -30℃ in order regardless of hardening. In comparison of the fatigue lives on the basis of tested result at 25℃, the fatigue lives of non-hardened.s.ecimens decreased about 35%, but that of hardened.s.ecimens decreased about only 5% at 80℃ more than at 25℃. And fatigue life of non-hardened and hardened.s.ecimens were about 110% and 120% higher at -30℃ than that of 25℃. Based on the result of stress d.s.ribution near the defect, the tensile and compressive stress repeatedly generated by load direction were the largest on the small circular defect due to the stress concentration.

关键词： induction hardening fatigue test front engine and front drive shaft,fatigue crack fatigue life fatigue life ratio

deviations of the lepton mapping matrix from the Harrison-Perkins-scott form

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Chinese Physics C 2010年第10期34卷 1547-1555页

作者： R.Friedberg T.d.lee Physics department Columbia UniversityNew York China Center of Advanced.s.ience and Technology(CCAsT/World Lab.)

We propose a simple set of hypotheses governing the deviations of the leptonic mapping matrix from the Harrison-Perkins-scott （HPs） form. These deviations are supposed to arise entirely from a perturbation of the mass matrix in the charged lepton sector. The perturbing matrix is assumed to be purely imaginary （thus maximally T-violating） and to have a strength in energy scale no greater （but perhaps smaller） than the muon mass. As we shall show, it then follows that the absolute value of the mapping matrix elements pertaining to the tau lepton deviate by no more than O（（mμ/mτ）^2） ≈ 3.5 ×10^-3 from their HPs values. Assuming that （mμ/mτ）^2 can be neglected, we derive two simple constraints on the four parameters θ12,θ23, θ31, and δ of the mapping matrix. These constraints are independent of the details of the imaginary T-violating perturbation of the charged lepton mass matrix. We also show that the e and μ parts of the mapping matrix have a definite form governed by two parameters α and β; any deviation of order mμ/mτ can be accommodated by adjusting these two parameters.

关键词： lepton mapping matrix CP and T violation Jarlskog invariant timeon

deposition of Nano-scaled Coatings Using Inductively Coupled Plasma

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Journal of Rare Earths 2004年第z2期22卷 153-156页

作者： d H Jung B Park J J lee school of Materials science and Engineering College of EngineeringSeoul National UniversitySeoul 151-744Korea School of Materials Science and EngineeringCollege of EngineeringSeoul National UniversitySeoul 151-744Korea School of Materials Science and EngineeringCollege of EngineeringSeoul National UniversitySeoul 151-744Korea

Nano-scaled Ti-B-N coatings could be produced by inductively coupled plasma (ICP) assisted magnetron spurtering. The properties and microstructure of the coating can be changed drastically by applying ICP to conventional magnetron sputtering. In this work, an internal type rf ICP process is used. The core of this technology is the efficient production and control of self-depositing ions and reactive gas ions by an induced electric field. Ti-B-N coatings were prepared by using a TiB2 target and a gas mixture of N2 and Ar at 200 ℃ and a pressure of 60 mTorr. In addition to ICP, the effect of the substrate bias voltage on the structure and properties of the coating was investigated. By applying ICP and a bias voltage to the substrate the hardness of the Ti-B-N coating is increased by more than 75 GPa, as a result of enhanced ionization in the plasma. The Ti-B-N coating, which has the highest hardness, shows the best surface uniformity and a very dense structure with a grain size of 3 nm. This sample also shows a high crystallinity compared to the coating prepared using other deposition parameters.

关键词： nano-scaled coatings ind.s.ively conpled plasma

Micromorphic theory:a gateway to nano world

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International Journal of smart and Nano Materials 2010年第2期1卷 115-135页

作者： Xianqiao Wang James d.lee department of Mechanical and Aerospace Engineering The George Washington UniversityWashingtonDC 20052USA

Micromorphic theory(MMT)envisions a material body as a continuous collection of deformable particles;each possesses finite size and inner *** is considered as the most successful top-down formulation of a two-level continuum model,in which the deformation is expressed as a sum of macroscopic continuous deformation and internal microscopic deformation of the inner *** this work,the kinematics including the objective Eringen tensors is *** laws are derived by requiring the energy equation to be form-invariant under the generalized Galilean *** concept of material force and the balance law of pseudomomentum are generalized for *** axiomatic approach is demonstrated in the formulation of constitutive equations for a generalized micromorphic thermoviscoelastic solid,generalized micromorphic fluid,micromorphic plasticity,and micromorphic electromagnetic-thermoelastic *** of MMT in micro/nanoscale are d.s.ussed.

关键词： micromorphic theory Eringen tensors constitutive theory generalized micromorphic solid/fluid electromagnetic-thermoelastic coupling micro/nanomechanics