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Review of Sodic Soil Reclamation with a Snapshot of Current Research Activity

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Chinese Geographical Science 2022年第6期32卷 1099-1109页

作者： tÓtH tibor Institute for Soil Sciences Centre for Agricultural ResearchBudapest 1022Hungary

For centuries, reclamation of sodic soils has been an essential part of cropping practices in several parts of the world. Parallel to increasing population, the need for new cropland constantly re-evaluates land suitability concepts. therefore, the importance of sodic soils as potential croplands is increasing worldwide. Although theoretically farmers can choose from a wide variety of reclamation options, according to profitability, business plans, and human and financial resources, in practice, few reclamation methods are applied at large scale. this article touches on the early history, 20th Century intensive research, and current trends of sodic soil reclamation. New approaches such as leaching, chemical amendments, addition of organic material, and biological and microbial improvements are discussed, and also brand-new approaches are reviewed. the early history is reviewed using historical books, the achievements of the last hundred years using basic technical literature, mostly books, and the current approaches of our time with fresh publications, mostly papers and two very recent conferences published in English.

关键词： gypsuming liming chemical reclamation new technology sodic soil

Precise measurement of magnetic moment of short-lived β-emitting nuclei ^(12)B (I~π=1^+,t_(1/2)=20.18 ms)

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Science China(Physics,Mechanics & Astronomy) 2004年第5期47卷 531-539页

作者： M. Mihara M. Fukuda K. Matsuta t. Minamisono Graduate School of Science Osaka University Toyonaka Osaka 560-0043 JapanGraduate School of Science Osaka University Toyonaka Osaka 560-0043 JapanGraduate School of Science Osaka University Toyonaka Osaka 560-0043 JapanGraduate School of Science Osaka University Toyonaka Osaka 560-0043 Japan

the spin polarized β-emitting nuclei12B (I π=1+,t 1/2=20.18 ms) were produced by the nuclear reaction11B(d, p)12B and by the selection technique of the incident deuteron energy and the12B recoil angle following the nuclear reaction. the nuclear magnetic moment of the short-lived nuclei12B was measured by β-NMR with the β-NMR and β-NQR setup established for the first time in China. the nuclear magnetic moment of12B was determined to be μ=0.99993±0.00048 nm org=0.99993±0.00048 after the precise correction of the Knight shift.

关键词： short-lived 12B (Iπ = 1+, t1/2 = 20.18 ms) nuclei, nuclear magnetic moment, Knight shift, β-NMR.

the Effect of Intraband transitions on the Optical Spectra of Metallic Carbon Nanotubes

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Chinese Physics Letters 2013年第7期30卷 172-175页

作者： t.Movlarooy Department of Physics University of ShahroodShahroodIran

First-principles calculations of the electronic structure and linear optical properties of metallic carbon nanotubes are carried out using the full-potential linear-augmented plane-wave *** effect of intraband transition and electric-field polarization on the optical spectra of(5,2)chiral,(15,0)zigzag,and(8,8)armchair metallic carbon nanotubes are *** optical spectra are calculated for both electric-field polarizations,parallel and perpendicular to the axis of the *** is revealed that the optical spectra are anisotropic along these two *** the parallel polarization to the tube axis,adding the intraband transition contributions shows that the dielectric function has singularity at zero frequency due to the screening effect in metallic carbon nanotubes.

关键词： polarization metallic band

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

Effects of gamma-ray irradiation on electronic and non-electronic equipment of Large Helical Device

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Plasma Science and technology 2017年第2期19卷 95-100页

作者： K OGAWA t NISHItANI M ISOBE M SAtO M YOKOtA H HAYASHI t KOBUCHI t NISHIMURA National Institute for Fusion Science National Institutes of Natural Sciences322-6 0roshi-choToki 509-5292Japan SOKENDAI(the Graduate University for Advanced Studies) School of Physical Sciences322-6 Oroshi-choTold 509-5292Japan

In a deuterium operation on the Large Helical Device, the measurement and control equipment placed in the toms hall must survive under an environment of radiation, to study the effects of gamma-ray irradiation on the equipment, an irradiation experiment is performed at the Cobalt-60 irradiation facility of Nagoya University. transient and permanent effects on a personal computer, media converters, programmable logic controllers, isolation amplifiers, a web camera, optical flow meters, and water sealing gaskets are experimentally surveyed. transient noise appears on the web camera. Offset of the signal increases with an increase of the integrated dose on the programmable logic controller. the DeviceNet module on the programmable logic controller is broken at the integrated dose of 72 Gy, which is the expected range of the integrated dose of the toms hall. the other equipment can survive under the gamma-ray field in the toms hall.

关键词： large helical device gamma-ray irradiation radiation effect

Examination of n-t_(9) conditions required by N=50,82,126 waiting points in r-process

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Communications in theoretical Physics 2021年第10期73卷 147-157页

作者： Nguyen Duy Ly Nguyen Ngoc Duy Nguyen Kim Uyen Vinh N t Pham Faculty of Fundamental Sciences Vanlang UniversityHo Chi Minh City 700000Vietnam Department of Physics Sungkyunkwan UniversitySuwon 16419Republic of Korea Department of Physics Ho Chi Minh City University of EducationHo Chi Minh City 700000Vietnam

We examined the conditions of neutron density(n) and temperature(t9) required for the N = 50, 82,and 126 isotopes to be waiting points(WP) in the r-process. the nuclear mass based on experimental data presented in the AME2020 database(AME and AME ± Δ) and that predicted using FRDM,WS4, DZ10, and KtUY models were employed in our estimations. We found that the conditions required by the N = 50 WP significantly overlap with those required by the N = 82 ones, except for the WS4 model. In addition, the upper(or lower) bounds of the n-t9 conditions based on the models are different from each other due to the deviations in the two-neutron separation *** standard deviations in the nuclear mass of 108 isotopes in the three N = 50, 82, and 126 groups are about rms = 0.192 and 0.434 Me V for the pairs of KtUY-AME and WS4-KtUY models,respectively. We found that these mass uncertainties result in a large discrepancy in the nn-t_(9) conditions, leading to significant differences in the conditions for simultaneously appearing all the three peaks in the r-process abundance. the newly updated FRDM and WS4 calculations can give the overall conditions for the appearance of all the peaks but vice versa for their old versions in a previous study. the change in the final r-process isotopic abundance due to the mass uncertainty is from a few factors to three orders of magnitude. therefore, accurate nuclear masses of the r-process key nuclei, especially for 76 Fe,81Cu,127Rh,132Cd,192Dy, and 197tm, are highly recommended to be measured in radioactive-ion beam facilities for a better understanding of the r-process evolution.

关键词： neutron capture r-process nuclear mass isotopic abundance precise mass measurement

Stochastic framework for modeling the linear apparent behavior of complex materials:Application to random porous materials with interphases

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Acta Mechanica Sinica 2013年第6期29卷 773-782页

作者： J.Guilleminot t.t.Le C.Soize Universit Paris-Est Laboratoire Modlisation et Simulation Multi EchelleMSME UMR8208 CNRS5 Bd Descartes77454 Marne la ValleFrance

this paper is concerned with the modeling of randomness in multiscale analysis of heterogeneous materials. More specifically, a framework dedicated to the stochastic modeling of random properties is first introduced. A probabilistic model for matrix-valued second-order random fields with symmetry propertries, recently proposed in the literature, is further reviewed. Algorithms adapted to the Monte Carlo simulation of the proposed representation are also provided. the derivations and calibration procedure are finally exemplified through the modeling of the apparent properties associated with an elastic porous microstructure containing stochastic interphases.

关键词： Apparent properties MaxEnt Probabilistic model

Characteristics of the Mach Disk in the Underexpanded Jet in which the Back Pressure Continuously Changes with time

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Journal of thermal Science 2003年第2期12卷 132-137页

作者： t.Irie t.Yasunobu H.Kashimura t.Setoguchi Department of Mechanical Engineering Kitakyushu National College of TechnologyShiiKokuraminami-kuKitakyushu 802-0985JapanDepartment of Control and Information Systems EngineeringKitakyushu National College of TechnologyShiiKokuraminami-kuKitakyushu 802-0985JapanDepartment of Control and Information Systems EngineeringKitakyushu National College of TechnologyShiiKokuraminami-kuKitakyushu 802-0985JapanDepartment of Mechanical EngineeringSaga UniversityHonjoSaga 840-8502Japan

When the high-pressure gas is exhausted to the vacuum chamber from the nozzle,the underexpanded supersonic jet contained with the Mach disk is generally *** eventual purpose of this study is to clarify the unsteady phenomenon of the underexpanded free jet when the back pressure continuously changes with *** characteristic of the Mach disk has been clarified in consideration of the diameter and position of it by the numerical analysis in this *** sonic jet of the exit Mach number Me=1 is assumed and the axisymmetric conservational equation is solved by the tVD method in the numerical *** diameter and position of the Mach disk differs with the results of a steady jet and the influence on the continuously changing of the back pressure is evidenced from the comparison with the case of steady supersonic jet.

关键词： underexpanded jet sonic jet regular reflection Mach reflection Mach disk tVD method.

Energy principle of ferroelectric ceramics and single domain mechanical model

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Acta Mechanica Sinica 2007年第5期23卷 531-543页

作者： t.C.Wang LNM Institute of MechanicsChinese Academy of SciencesBeijing 100080China

Many physical experiments have shown that the domain switching in a ferroelectric material is a complicated evolution process of the domain wall with the variation of stress and electric field. According to this mechanism, the volume fraction of the domain switching is introduced in the constitutive law of ferroelectric ceramic and used to study the nonlinear constitutive behavior of ferroelectric body in this paper. the principle of stationary total energy is put forward in which the basic unknown quantities are the displacement ui, electric displacement Di and volume fraction pI of the domain switching for the variant I. Mechanical field equation and a new domain switching criterion are obtained from the principle of stationary total energy. the domain switching criterion proposed in this paper is an expansion and development of the energy criterion. On the basis of the domain switching criterion, a set of linear algebraic equations for the volume fraction PI of domain switching is obtained, in which the coefficients of the linear algebraic equations only contain the unknown strain and electric fields. then a single domain mechanical model is proposed in this paper. the poled ferroelectric specimen is considered as a transversely isotropic single domain. By using the partial experimental results, the hardening relation between the driving force of domain switching and the volume fraction of domain switching can be calibrated. then the electromechanical response can be calculated on the basis of the calibrated hardening relation. the results involve the electric butterfly shaped curves of axial strain versus axial electric field, the hysteresis loops of electric displacement versus electric filed and the evo- lution process of the domain switching in the ferroelectric specimens under uniaxial coupled stress and electric field loading. the present theoretic prediction agrees reasonably with the experimental results given by Lynch.

关键词： Ferroelectric ceramic Domain switching the volume fraction of domain switching Single domain mechanical model