From Finite Nuclei to Neutron Stars: The Essential Role of High-Order Density Dependence in Effective Forces

A unified description of finite nuclei and equation of state of neutron stars presents both a major challenge and also opportunities for understanding nuclear interactions.Inspired by the Lee-Huang-Yang formula of hardsphere gases,we develop effective nuclear interactions with an additional high-order density dependent term.While the original Skyrme force SLy4 is widely used in studies of neutron stars,there are not satisfactory global descriptions of finite nuclei.The refitted SLy4' force can improve descriptions of finite nuclei but slightly reduces the radius of neutron star of 1.4 M_☉ with M_☉ being the solar mass.We find that the extended SLy4 force with a higher-order density dependence can properly describe properties of both finite nuclei and GW170817 binary neutron stars,including the mass-radius relation and the tidal deformability.This demonstrates the essential role of high-order density dependence at ultrahigh densities.Our work provides a unified and predictive model for neutron stars,as well as new insights for the future development of effective interactions.

A Method of Evaluating the Effectiveness of a Hydraulic Oscillator in Horizontal Wells

Bent-housing motor is the most widely used directional drilling tool,but it often encounters the problem of high friction when sliding drilling in horizontal wells.In this paper,a mathematical model is proposed to simulate slide drilling with a friction reduction tool of axial vibration.A term called dynamic effective tractoring force(DETF)is defined and used to evaluate friction reduction effectiveness.The factors influencing the DETF are studied,and the tool placement optimization problem is investigated.The studyfinds that the drilling rate of penetration(ROP)can lower the DETF but does not change the trend of the DETF curve.To effectively work,the shock tool stiffness must be greater than some critical value.For the case study,the best oscillating frequency is within 15∼20 Hz.The reflection of the vibration at the bit boundary can intensify or weaken the friction reduction effec-tiveness,depending on the distance between the hydraulic oscillator and the bit.The optimal placement position corresponds to the plateau stage of the DETF curve.The reliability of the method is verified by thefield tests.The proposed method can provide a design and use guide to hydraulic oscillators and improve friction reduction effectiveness in horizontal wells.

Agglomeration rate and action forces between atomized particles of agglomerator and inhaled-particles from coal combustion

In order to remove efficiently haled-particles emissions from coal combustions, a new way was used to put forward the process of agglomeration and the atomization was produced by the nozzle and then sprayed into the flue before precipitation devices of power station boiler in order to make inhaled-particles agglomerate into bigger particles, which can be easily removed but not change existing running conditions of boiler. According to this idea, a model is set up to study agglomeration rate and effect forces between fly ash inhaled-particles and atomized agglomerator particles. The developed agglomeration rate was expressed by relative particle number decreasing speed per unit volume. The result showed that viscosity force and flow resistance force give main influences on agglomeration effect of inhaled-particles, while springiness force and gravity have little effect on agglomeration effect of theirs. Factors influencing the agglomeration rate and effect forces are studied, including agglomerator concentration, agglomerator flux and agglomerator density, atomized-particles diameters and inhaled-particles diameter and so on.

A Modeling Study of Effective Radiative Forcing and Climate Response Due to Tropospheric Ozone

This study simulates the effective radiative forcing （ERF） of tropospheric ozone from 1850 to 2013 and its effects on global climate using an aerosol-climate coupled model, BCC_AGCM2.0. I_CUACE/Aero, in combination with OMI （Ozone Monitoring Instrument） satellite ozone data. According to the OMI observations, the global annual mean tropospheric col- umn ozone （TCO） was 33.9 DU in 2013, and the largest TCO was distributed in the belts between 30°N and 45°N and at approximately 30°S; the annual mean TCO was higher in the Northern Hemisphere than that in the Southern Hemisphere; and in boreal summer and autumn, the global mean TCO was higher than in winter and spring. The simulated ERF due to the change in tropospheric ozone concentration from 1850 to 2013 was 0.46 W m-2, thereby causing an increase in the global annual mean surface temperature by 0.36°C, and precipitation by 0.02 mm d-1 （the increase of surface temperature had a significance level above 95%）. The surface temperature was increased more obviously over the high latitudes in both hemispheres, with the maximum exceeding 1.4°C in Siberia. There were opposite changes in precipitation near the equator, with an increase of 0.5 mm d- 1 near the Hawaiian Islands and a decrease of about -0.6 mm d- 1 near the middle of the Indian Ocean.

The Shielding Effect of Multi-Pile Structures on Ice Force

The shielding effect of the front pile-row on the ice force acting on the back pile-row is studied by ice force model tests. In the tests, the front pile-row is designed to model jacket legs and the back pile-row to model the water resisting pipe-phalanx within the jacket. The shielding factor for ice force corresponding to different conditions are given in this paper. The research indicates that there are many factors, including the longitudinal and lateral spacing between the front and back pile-row, ice attacking angle and the ratio of pile diameter to ice thickness, that influence the shielding effect on ice force.

Interference effects of two and three super-tall buildings under wind action

Most previous investigations on interference effects of tall buildings under wind actions focused on the wind induced interference effects between two buildings,and the interference effects of three or more buildings have seldom been studied so far due to the huge workload involved in experiments and data processing.In this paper,mean and dynamic force/response interference effects and peak wind pressure interference effects of two and three tall buildings,especially the three-building configuration,are investigated through a series of wind tunnel tests on typical tall building models using high frequency force balance technique and wind pressure measurements.Furthermore,the present paper focuses on the effects of parameters,including breadth ratio and height ratio of the buildings and terrain category,on the interference factors and derives relevant regression results for the interference factors.

Derivation of energy-based base shear force coefficient considering hysteretic behavior and P-delta effects

A modified energy-balance equation accounting for P-delta effects and hysteretic behavior of reinforced concrete members is derived. Reduced hysteretic properties of structural components due to combined stiffness and strength degradation and pinching effects, and hysteretic damping are taken into account in a simple manner by utilizing plastic energy and seismic input energy modification factors. Having a pre-selected yield mechanism, energy balance of structure in inelastic range is considered. P-delta effects are included in derived equation by adding the external work of gravity loads to the work of equivalent inertia forces and equating the total external work to the modified plastic energy. Earthquake energy input to multi degree of freedom（MDOF） system is approximated by using the modal energy-decomposition. Energybased base shear coefficients are verified by means of both pushover analysis and nonlinear time history（NLTH） analysis of several RC frames having different number of stories. NLTH analyses of frames are performed by using the time histories of ten scaled ground motions compatible with elastic design acceleration spectrum and fulfilling duration/amplitude related requirements of Turkish Seismic Design Code. The observed correlation between energy-based base shear force coefficients and the average base shear force coefficients of NLTH analyses provides a reasonable confidence in estimation of nonlinear base shear force capacity of frames by using the derived equation.

Antidepressant Effects of Ginsenosides from Panax notoginseng

Ginsenosides Rg 1,Rb 1,R 1,Rd,and Re are major constituents of Panax notoginseng,a famous traditional Chinese medicinal herb,which has both stimulative and inhibitory effects on the central nervous system (CNS).The monoamine hypothesis proposes that depression is a result of the depletion of 5-hydroxytryptamine (5-HT),norepinephrine (NE) and dopamine (DA) in addition to the activation of monoamine oxidase in the CNS.The purpose of this study was to determine whether P.notoginseng Saponin (PNS) has an antidepressant activity.We investigated the antidepressant-like activities of Rg 1,Rb 1,R 1,Rd,and Re in mice,using two animal models of depression.In addition,we analyzed the neurochemicals by the chronic unpredictable mild stress test.Our results showed that Rb 1,Rd,and Re treatment at 10 mg kg-1 significantly reduced the duration of immobility in both the tail suspension and forced swimming tests.Rb 1,Rd,and Re increases in 5HT and NE levels at 10 mg kg-1 in both the frontal cortex and hippocampus.Dopamine levels increased in the hippocampus and the striatum.Moreover,5-hydroxyindoleacetic acid (5-HIAA) levels were found increased in the hippocampus.These findings suggest that the antidepressant effects of Rb 1,Rd,and Re may be related to the increase in 5-HT and NE in the CNS,and through the alterations in the synthesis or metabolism of dopamine.

A discussion on Corioli force effect and aftershock activity tendency of the M=8.1 Kunlun Mountain Pass earthquake on Nov. 14, 2001

Following the theory and definition of the Corioli force in physics, the Corioli force at the site of the M=8.1 Kunlun Mountain Pass earthquake on November 14, 2001, is examined in this paper on the basis of a statistical research on relationship between the Corioli force effect and the maximum aftershock magnitude of 20 earthquakes with M7.5 in Chinese mainland, and then the variation tendency of aftershock activity of the M=8.1 earthquake is discussed. The result shows: a) Analyzing the Corioli force effect is an effective method to predict maximum aftershock magnitude of large earthquakes in Chinese mainland. For the sinistral slip fault and the reverse fault with its hanging wall moving toward the right side of the cross-focus meridian plane, their Corioli force pulls the two fault walls apart, decreasing frictional resistance on fault plane during the fault movement and releasing elastic energy of the mainshock fully, so the maximum magnitude of aftershocks would be low. For the dextral slip fault, its Corioli force presses the two walls against each other and increases the frictional resistance on fault plane, prohibiting energy release of the mainshock, so the maximum magnitude of aftershocks would be high. b) The fault of the M=8.1 Kunlun Mountain earthquake on Nov. 14, 2001 is essentially a sinistral strike-slip fault, and the Corioli force pulled the two fault walls apart. Magnitude of the induced stress is about 0.06 MPa. After a comparison analysis, we suggest that the aftershock activity level will not be high in the late period of this earthquake sequence, and the maximum magnitude of the whole aftershocks sequence is estimated to be about 6.0.

The Effect of Topographic Forcing on the Formation and Maintenance of Blocking

A barotropic channel model in β-plane is used to study the effect of topographic forcing on the formation and maintenance of blocking. The approximate analytical solution of potential vorticity equation can show the main property of the whole process of blocking. It is indicated that the topographic forcing is one of the main factors causing the blocking process. The results suggest that the nonlinear interaction plays a very important role in the stable 'Ω' situation of blocking. The atmospheric circulation with periodic and low-frequency oscillation, perhaps, is partly caused by topographic forcing.

The driving force effect of trade embodied carbon emissions and embodied SO_(2) emissions transferred in resources-rich areas: A case study of Shanxi province

SDA (Structural Decomposition Analysis) model was applied to analyze the driving factors of embodied carbon and SO_(2) emissions transferred in Shanxi during 2007-2012 based on the input-output model from the perspectives of region and industry.The results showed that the change of embodied carbon emissions and embodied SO_(2) emissions of Shanxi and other regions were hindered by the carbon (sulfur) emissions strength effect,but promoted by the intermediate (final) demand scale effect,the intermediate (final) structure effect and the input-output structure effect.The carbon emissions strength effect had a significant contribution to reducing the embodied carbon emissions transferred from industries in Shanxi to other regions.The intermediate (final) demand scale effect was the driving factor to increase the embodied carbon emissions transferred from industries in Shanxi to other regions.The sulfur emissions strength effect was the only factor that reduced the embodied SO_(2) emissions transferred from Shanxi to other industries.The change of embodied carbon emissions from industries in other regions to Shanxi was hindered by the carbon emissions strength effect,but the input-output structure effect and final demand scale effect both increased the embodied carbon emissions from industries in other regions to Shanxi.The change of the embodied SO_(2) emissions transferred from industries in other regions to Shanxi was inhibited by the sulfur emissions strength effect,but the input-output structure effect,the intermediate demand structure effect and the final demand scale effect were both the driving force effect of increasing the embodied SO_(2) emissions transferred from industries in other regions to Shanxi.The corresponding suggestions and measures were put forward.

A glance on the effects of temperature on axisymmetric dynamic behavior of multiwall carbon nanotubes

In this paper the effects of temperature on the radial breathing modes （RBMs） and radial wave propaga- tion in multiwall carbon nanotubes （MWCNTs） are inves- tigated using a continuum model of multiple elastic isotropic shells. The van der Waals forces between tubes are simulated as a nonlinear function of interlayer spacing of MWCNTs. The governing equations are solved using a finite element method. A wide range of innermost radius-to-thickness ratio of MWCNTs is considered to enhance the investigation. The presented solution is verified by comparing the results with those reported in the literature. The effects of temperature on the van der Waals interaction coefficient between layers of MWCNTs are examined. It is found that the variation of the van der Waals interaction coefficient at high temperature is sensible. Subsequently, variations of RBM frequencies and radial wave propagation in MWCNTs with temperatures up to 1 600 K are illustrated. It is shown that the thick MWC- NTs are more sensible to temperature than the thin ones.

Analysis of influencing factors of excitation parameters for magnetoacoustic tomography with current injection

Magneto-acoustic tomography with current injection(MAT-CI) is a type of hybrid imaging;under the excitation of the static magnetic field, the thermoacoustic effect and the Lorentz force effect will exist at the same time. Therefore,the detected signal is a mixed signal generated by the simultaneous action of the two effects, but the influence of excitation parameters on the two effects is different. In this paper, for objects with different conductivity, the proportion of thermoacoustic signal(TA) and magneto-acoustic signal(MA) in the mixed signal is quantitatively analyzed in terms of three aspects: the magnetic induction intensity, pulse excitation and injection current polarity. Experimental and simulation analyses show that the intensity ratio of MA to TA is not affected when the conductivity varies from 0.1 S/m to 1.5 S/m and other conditions remain unchanged. When the amplitude of the pulse excitation and the strength of the magnetic induction are different, the growth rates of MA and TA are different, which has a significant impact on the proportion of the two signals in the mixed signal. At the same time, due to the Lorentz force effect, MA is affected by the polarity of the injected current and the direction of the static magnetic field. The combination of the static magnetic field and the injected current can not only distinguish the two signals in the mixed signal, but also effectively enhance the intensity of the mixed signal and improve the quality of the reconstructed image.

Mesoplasticity Approach to Studies of the Cutting Mechanism in Ultra-precision Machining

There have been various theoretical attempts by researchers worldwide to link up different scales of plasticity studies from the nano-, micro- and macro-scale of observation, based on molecular dynamics, crystal plasticity and continuum mechanics. Very few attempts, however, have been reported in ultra-precision machining studies. A mesoplasticity approach advocated by Lee and Yang is adopted by the authors and is successfully applied to studies of the micro-cutting mechanisms in ultra-precision machining. Traditionally, the shear angle in metal cutting, as well as the cutting force variation, can only be determined from cutting tests. In the pioneering work of the authors, the use of mesoplasticity theory enables prediction of the fluctuation of the shear angle and micro-cutting force, shear band formation, chip morphology in diamond turning and size effect in nano-indentation. These findings are verified by experiments. The mesoplasticity formulation opens up a new direction of studies to enable how the plastic behaviour of materials and their constitutive representations in deformation processing, such as machining can be predicted, assessed and deduced from the basic properties of the materials measurable at the microscale.

A Neo Explanation of the"Mass-Velocity Relation

A reinterpretation of the well-known formula of the 'mass-velocity relation' is exactlyderived from a new viewpoint with new concepts, such as the finiteness of the transmitting velocityof force (TVF), effective action, and the coupled effect of the TVF for two EM fields, etc. Then, atrue meaning hidden in the Lorentz factor is exploited : i.e., when a charged particle is moving at aspeed v under an EM field, the effective action exerted on it by the field varies inversely with thespeed ratio β= v / U, where U is the TVF, which probably is equal to the propagation velocity ofEM field. The actual reduction of the effective action gives a false impression of mass gain.Accordingly, it is a major mistake in orientation to ascribe the (genuine) electrodynamics of movingbodies to any observation, or to any motion of an observer, while disregarding the facts of mutualaction.

Electron Transport under the Influence of Two Kinds of Friction in an Electron-Deuteron Plasma

We discuss an electron transport in an ideal plasma which consists of electrons and deuterons. With respect to a frictional force to suppress an unlimited increase of a drift velocity, the Boltzmann equation with the Fokker-Planck collision term takes into consideration only a dynamical frictional force coming from the many-body collisions through the Coulomb force. However, we here bring forward a problem that there may be another frictional force besides the dynamical frictional force. Another frictional force was found in the weakly ionized plasma and appears only in the case where free paths (nearly straight lines in no external force field) can be defined. Then, we have inquired into the existence of physical quantities like free paths (or free times) in the field of the scattering through the Coulomb force and the existence of an effective radius of the Coulomb force of a deuteron.

Piezotronic effect on the luminescence of quantum dots for micro/nano-newton force measurement

The luminescence of semiconductor quantum dots （QDs） can be adjusted using the piezotronic effect. An external mechanical force applied on the QD generates a piezoelectric potential, which alters the luminescence of the QD. A small mechanical force may induce a significant change on the emission spectrum. In the case of InN QDs, it is demonstrated that the unforced emission wavelength is more than doubled by a force of 1 μN. The strategy of using the piezotronic effect to tune the color of the emission leads to promising noncontact force- measurement applications in biological and medical sensors and force-sensitive displays. Several piezoelectric semiconductor materials have been investigated in terms of the tunability of the emission wavelength in the presence of an external applied force. It is found that CdS and CdSe demonstrate much higher tunability δλ/δF, which makes them suitable for micro/nano-newton force measurement applications.

EFFECT OF THE THERMAL FORCING ON THE SECONDARY CIRCULATION OF TYPHOONS

A non-dimensional secondary circulation equation for typhoons has been derived and then 11-yr com- positing typhoon data were used to estimate the thermally forced secondary circulation.The main results have been obtained as follows: (1)The diabatic heating and Cu vertical heat mixing are major thermal forcing factors.They have the same magnitude of order.(2)The effects of eddy flux and Cu horizontal mixing of heat are of minor im- portance.(3)Ekman pumping and Cu vertical heat mixing cooperatively work.This feedback process is favorable for the enhancement of the secondary circulation of typhoons.

Effect of tensor correlations on the depletion of nuclear Fermi sea within the extended BHF approach

We have investigated the effect of tensor correlations on the depletion of the nuclear Fermi sea in symmetric nuclear matter within the framework of the extended Brueckner-Hartree-Fock approach by adopting the AV 18 two-body interaction and a microscopic three-body force.The contributions from various partial wave channels including the isospin-singlet T = 0 channel,the isospin-triplet T = 1 channel and the T = 0 tensor 3SD1 channel have been calculated.The T =0 neutron-proton correlations play a dominant role in causing the depletion of nuclear Fermi sea.The T =0 correlation-induced depletion turns out to stem almost completely from the 3SD1 tensor channel.The isospin-singlet T = 0 3SD1 tensor correlations are shown to be responsible for most of the depletion,which amounts to more than 70 percent of the total depletion in the density region considered.The three-body force turns out to lead to an enhancement of the depletion at high densities well above the empirical saturation density and its effect increases as a function of density.

The lubrication performance of water lubricated bearing with consideration of wall slip and inertial force

The lubrication mechanism and the performance parameters with consideration of wall slip and inertial force are studied in this paper. Based on the modified Reynolds equation, the finite difference method is used to study the lubrication mechanism and the performance. Effects of the wall slip and the inertial force on the performance parameters are obtained, and found in good agreement with the results of FLUENT. It is shown that the wall slip and the inertial force do not significantly change the distribution of the pressure, the load capacity and the friction force. The inertial force slightly increases the pressure and the load capacity by 1.2% and 4.8%, while the wall slip reduces them by 8.0% and 17.85%. The wall slip and the inertial force increase the friction by about 15.98%, 2.33%, respectively. Compared with the wall slip, the inertial force is smaller, but cannot be neglected.