非k积态基于Sandwiched Renyi相对熵的关联测度

在量子信息理论中,Sandwiched Renyi相对熵具有极其重要的应用价值。该研究给出多体复合系统非k积态基于Sandwiched Renyi相对熵的关联测度,同时证明了其满足量子关联度的一些必要性质,包括非负性,酉不变性,在完全正的保迹线性映射下的单调性,联合凸性以及在非相干辅助子系统影响下的不变性。

Double casing warhead with sandwiched charge:The axial distribution of fragments velocities

The double casing warhead with sandwiched charge is a novel fragmentation warhead that can produce two groups of fragments with different velocity,and the previous work has presented a calculation formula to determine the maximum fragment velocity.The current work builds on the published formula to further develop a formula for calculating the axial distribution characteristics of the fragment velocity.For this type of warhead,the simulation of the dispersion characteristics of the detonation products at different positions shows that the detonation products at the ends have a much larger axial velocity than those in the middle,and the detonation products have a greater axial dispersion velocity when they are closer to the central axis.The loading process and the fragment velocity vary with the axial position for both casing layers,and the total velocity of the fragments is the vector sum of the radial velocity and the axial velocity.At the same axial position,the acceleration time of the inner casing is greater than that of the outer casing.For the same casing,the fragments generated at the ends have a longer acceleration time than the fragments from the middle.The proposed formula is validated with the X-ray radiography results of the four warheads previously tested experimentally and the 3D smoothedparticle hydrodynamics numerical simulation results of several series of new warheads with different configurations.The formula can accurately and reliably calculate the fragment velocity when the lengthto-diameter ratio of the charge is greater than 1.5 and the thickness of the casing is less than 20%its inner radius.This work thus provides a key reference for the theoretical analysis and the design of warheads with multiple casings.

Phonon Thermal Transport at Interfaces of a Graphene/Vertically Aligned Carbon Nanotubes/Hexagonal Boron Nitride Sandwiched Heterostructure

Molecular dynamics simulation is used to calculate the interfacial thermal resistance of a graphene/carbon nanotubes/hexagonal boron nitride(Gr/CNTs/hBN)sandwiched heterostructure,in which vertically aligned carbon nanotube(VACNT)arrays are covalently bonded to graphene and hexagonal boron nitride layers.We find that the interfacial thermal resistance(ITR)of the Gr/VACNT/hBN sandwiched heterostructure is one to two orders of magnitude smaller than the ITR of a Gr/hBN van der Waals heterostructure with the same plane size.It is observed that covalent bonding effectively enhances the phonon coupling between Gr and hBN layers,resulting in an increase in the overlap factor of phonon density of states between Gr and hBN,thus reducing the ITR of Gr and hBN.In addition,the chirality,size(diameter and length),and packing density of sandwich-layer VACNTs have an important influence on the ITR of the heterostructure.Under the same CNT diameter and length,the ITR of the sandwiched heterostructure with armchair-shaped VACNTs is higher than that of the sandwiched heterostructure with zigzag-shaped VACNTs due to the different chemical bonding of chiral CNTs with Gr and hBN.When the armchair-shaped CNT diameter increases or the length decreases,the ITR of the sandwiched heterostructure tends to decrease.Moreover,the increase in the VACNT packing density also leads to a continuous decrease in the ITR of the sandwiched heterostructure,attributed to the extremely high intrinsic thermal conductivity of CNTs and the increase of out-of-plane heat transfer channels.This work may be helpful for understanding the mechanism for ITR in multilayer vertical heterostructures,and provides theoretical guidance for a new strategy to regulate the interlayer thermal resistance of heterostructures by optimizing the design of sandwich layer thermal interface materials.

Sandwiched Renyi量子相对熵单调性的另一证明

量子相对熵在保迹完全正定的映射作用下是单调递减的.此外,对于一种新提出的Sandwiched Renyi量子相对熵,当映射满足Schwarz不等式或映射保迹正定时,也有研究证明该量子相对熵的单调性也成立.本文利用复插值技巧给出当α∈[1/2,1)时Sandwiched Renyi量子相对熵单调性的另一证明.该技巧曾被用于证明α∈(1,∞)时量子相对熵在保迹正定映射的作用下满足单调性.

Seismic reflection and transmission coefficients of a single layer sandwiched between two dissimilar poroelastic solids

The seismic reflection and transmission characteristics of a single layer sandwiched between two dissimilar poroelastic solids saturated with two immiscible viscous fluids are investigated. The sandwiched layer is modeled as a porous solid with finite thickness. The propagation of waves is represented with potential functions. The displacements of particles in different phases of the aggregate are defined in terms of these potential functions. Due to the presence of viscosity in pore fluids, the reflected and transmitted waves are inhomogeneous in nature, i.e., with different directions of propagation and attenuation. The closed-form analytical expressions for reflection and transmission coefficients are derived theoretically for appropriate boundary conditions. These expressions are calculated as a non-singular system of linear algebraic equations and depend on the various parameters involved in this non-singular system. Hence,numerical examples are studied to determine the effects of various properties of the sandwich layer on reflection and transmission coefficients. The essential features of layer thickness, incident direction, wave frequency, liquidsaturation and capillary pressure of the porous layer on reflection and transmission coefficients are depicted graphically and discussed. The analysis shows that reflection and transmission coefficients are strongly associated with incident direction and various properties of the porous layer.

Reflection and transmission of elastic waves through a couple-stress elastic slab sandwiched between two half-spaces

The reflection and transmission of elastic waves through a couple-stress elastic slab that is sandwiched between two couple-stress elastic half-spaces are studied in this paper. Because of the couple-stress effects, there are three types of elastic waves in the couple-stress elastic solid, two of which are dispersive. The interface conditions between two couple-stress solids involve the surface couple and rotation apart from the surface traction and displacement. The nontraditional interface conditions between the slab and two solid half-spaces are used to obtain the linear algebraic equation sets from which the amplitude ratios of reflection and transmission waves to the incident wave can be determined. Then,the energy fluxes carried by the various reflection and transmission waves are calculated numerically and the normal energy flux conservation is used to validate the numerical results. The special case, couple-stress elastic slab sandwiched by the classical elastic half-spaces, is also studied and compared with the situation that the classical elastic slab sandwiched by the classical elastic half-spaces. Incident longitudinal wave(P wave) and incident transverse wave(SV wave) are both considered. The influences of the couplestress are mainly discussed based on the numerical results.It is found that the couple-stress mainly influences the transverse modes of elastic waves.

H infinity Control for Sandwiched Maglev Stage with Dynamic Damping

An H infinity(H∞)controller for a sandwiched maglev positioning stage is proposed.The maglev positioning stage has a special structure:a sandwiched maglev stage,consisting of repulsive linear motors and attractive linear motors,which have better levitation performance.Forces on the sandwiched maglev stage are analyzed and modeled.The positioning controller is designed based on the feedback linearized model with a dynamic damping system.The design of the H infinity controller for stage positioning is derived as a series of linear matrix inequalities(LMIs)which are efficiently solved in Matlab.The proposed controller and its effectiveness is demonstrated compared to PID method.

Boosting Lithium Storage in Graphene-Sandwiched Cathodes Containing Multi-Carbonyl Polyquinoneimine Nanosheets

Carbonyl polymers as booming electrode materials for lithium-organic batteries are currently limited by low practical capacities and poor rate performance due to their inherent electronic insulation and microscopic agglomeration morphologies.Herein graphene/carbonyl-enriched polyquinoneimine(PQI@Gr)composites were readily prepared by in situ hydrothermal polycondensation of dianhydride and anthraquinone co-monomer salts in the presence of graphene oxide(GO).Conductive graphene sheets derived from hydrothermal reduction of GO are fully sandwiched between densely interlaced quinone-containing polyimide nanosheets.Remarkably,the as-fabricated PQI@Gr cathodes exhibit much larger specific capacity(205 mAh g^(-1)at 0.1 A g^(-1)),higher carbonyl utilization(up to 89.9%),and better rate capability(179.4 mAh g^(-1)at 5.0 A g^(-1))due to a surface-dominated capacitive process via fast kinetics compared to bare PQI electrode(162.5 mAh g^(-1)at 0.1 A g^(-1);67.5%;96.9 mAh g^(-1)at 5 A g^(-1)).The capacity retention as high as 73%for PQI@Gr is also achieved over ultra-long 10000 cycles at 5.0 A g^(-1).Such outstanding electrochemical performances are attributable to the combined merits of polyimides and polyquinones,and robust 3D hierarchical heterostructures with efficient conductive networks,abundant porous channels for electrolyte infiltration and ion accessibility,and highly exposed carbonyl groups.This work offers new insights into the development of high-performance polymer electrodes for sustainable batteries.

Multi-field coupling and free vibration of a sandwiched functionally-graded piezoelectric semiconductor plate

Sandwiched functionally-graded piezoelectric semiconductor(FGPS)plates possess high strength and excellent piezoelectric and semiconductor properties,and have significant potential applications in micro-electro-mechanical systems.The multi-field coupling and free vibration of a sandwiched FGPS plate are studied,and the governing equation and natural frequency are derived with the consideration of electron movement.The material properties in the functionally-graded layers are assumed to vary smoothly,and the first-order shear deformation theory is introduced to derive the multi-field coupling in the plate.The total strain energy of the plate is obtained,and the governing equations are presented by using Hamilton’s principle.By introducing the boundary conditions,the coupling physical fields are solved.In numerical examples,the natural frequencies of sandwiched FGPS plates under different geometrical and physical parameters are discussed.It is found that the initial electron density can be used to modulate the natural frequencies and vibrational displacement of sandwiched FGPS plates in the case of nano-size.The effects of the material properties of FGPS layers on the natural frequencies are also examined in detail.

Coherence measures based on sandwiched Rényi relative entropy

Coherence is a fundamental ingredient for quantum physics and a key resource for quantum information theory.Baumgratz,Cramer and Plenio established a rigorous framework(BCP framework)for quantifying coherence[Baumgratz T,Cramer M and Plenio M B Phys.Rev.Lett.113140401(2014)].In the present paper,under the BCP framework we provide two classes of coherence measures based on the sandwiched Rényi relative entropy.We also prove that we cannot get a new coherence measure f(C(·))by a function f acting on a given coherence measure C.

A Mini Review on Natural Fiber Honeycomb (NFH) Sandwiched Structure Composite: Flexural Perfomance Perspective

Natural Fiber Honeycomb (NFH) sandwiched structure composite is a type of composite that uses natural fiber as the reinforcement material and honeycomb structure in the form of a sandwich panel. The demand for commercial use of natural fiber-based composites is increasing in the past few years in many industrial sectors. The increase in popularity of natural fibers is because of their particular properties, price, health benefits, and recyclability. This paper aims to analyze the data and analysis of the past research about NFH sandwiched structure composite in terms of the materials used to make the NFH, the physical and mechanical properties, and their applications. Based on the literature review conducted, there were many types of materials used to make the NFH sandwiched structure composite. Some experimental tests were planned and conducted to analyze the mechanical properties of the NFH and its potential to be used in the desired industries. However, there are not many implementations of NFH composite in the construction industry. This is due to the concern related to the issue of the structural integrity of the NFH composite. From the literature review conducted, most of the research shows a positive analysis of the mechanical properties and the potential of the developed NFH to be used for the targeted industry in the study. Therefore, it can be observed that the material used in this study has a high potential to be used in the construction industry.

Electronic Transport Properties of Diblock Co-Oligomer Molecule Devices Sandwiched between Nitrogen Doping Armchair Graphene Nanoribbon Electrodes

We investigate the electronic transport properties of dipyrimidinyl-diphenyl sandwiched between two armchair graphene nanoribbon electrodes using the nonequilibrium Green function formalism combined with a first-principles method based on density functional theory. Among the three models M1–M3, M1 is not doped with a heteroatom. In the left parts of M2 and M3, nitrogen atoms are doped at two edges of the nanoribbon. In the right parts, nitrogen atoms are doped at one center and at the edges of M2 and M3, respectively. Comparisons of M1, M2 and M3 show obvious rectifying characteristics, and the maximum rectification ratios are up to 42.9 in M2. The results show that the rectifying behavior is strongly dependent on the doping position of electrodes. A higher rectification ratio can be found in the dipyrimidinyl-diphenyl molecular device with asymmetric doping of left and right electrodes, which suggests that this system has a broader application in future logic and memory devices.

Adaptive Backstepping Compensation of Drives with Sandwiched Deadzone Nonlinearity

In this paper, a nonlinear robust adaptive controller is proposed for gear transmission servo system (GTS) containing a sandwiched deadzone due to improper gear meshing. The controller is robust to dynamic uncertainties and can compensate the effect caused by the sandwiched nonlinearity which is separated from the control input through drive compliance. The proposed design methodology does not require an adaptive inverse deadzone function and does not require the knowledge of its parameter and only the knowledge of upper bounds is required.

NYEMO:SANDWICHED BETWEEN -TSANG

About 147kilometers from Lhasa,Nyemo County sits in the centralsouthern part of the Tibet Autonomous Region.Geologically and culturally,it lies in the buffer zone between the area centered around Lhasa()and the area centered around Shigatse(Tsang).There is an old saying in Tibet:"Nyemo is sandwiched betweenand Tsang",

Frequency and Field Dependences of Giant Magneto-Impedance Effect in Sandwiched FeCuCrVSiB Films

The giant magneto-impedance(GMI)effect has been investigated in sandwiched FeCuCrVSiB films annealed at 300℃ for 1.5 h.The frequency and field dependences of the GMI have been observed in the frequency range from 50 kHz to 13 MHz.The GMI ratio increases at first with increasing frequency,and reaches its maximum value of 136%at a very low characteristic frequency of about 4 MHz,and then decreases with further increasing frequency.These superior properties are related to the special structure of the sandwiched films.

Sandwiched N-carbon@Co_(9)S_(8)@Graphene nanosheets as high capacity anode for both half and full lithium-ion batteries

Transition metal sulfides(TMSs) are promising candidates for replacing graphite anode in LIBs. However,the low conductivity and structural collapse caused by the large volume change during lithium insertion and extraction greatly limit its application. Herein, we report a unique design of a two-dimensional(2 D) sandwich structure of N-doped carbon@Co9 S8@graphene(N–C@Co9 S8@G) with multilayer structure. Electrochemical tests reveal that the N–C@Co9 S8@G nanosheets possess a high reversible capacity(1009 mAhg^(-1) at 0.1 Ag^(-1)), and excellent rate capability(422mAhg^(-1) at 10 Ag^(-1)) and long cycle life(853 m Ahg^(-1) at 1Ag^(-1) for 500 cycles). Experimental studies reveal that capacitive storage contributes to the high reversible capacity. The lithium storage kinetics are studied by Galvanostatic intermittent titration technique(GITT) and electrochemical impedance spectroscopy(EIS). Meanwhile, the potential of N–C@Co9 S8@G anode in a full cell using Li Co O2 as the cathode is also demonstrated, exhibiting a high reversible capacity of 300mAhg^(-1) cycles at 0.1Ag^(-1). The strategy proposed in this work paves the way to engineering high performance anodes in LIBs.

Giant Magneto-Impedance Effect in Sandwiched FeSiB/Cu/FeSiB Films

Giant magneto-impedance(GMI)effect has been realized in the sandwiched FeSiB/Cu/FeSiB films.With magnetic field Ha and ac current applied along the longitudinal direction of the sample,the GMI ratio increases with the increasing Ha,reaching a positive maximum value,and then decreases to negative values with further increase of magnetic field.Field dependence of the GMI ratio also indicates that the magnetic field corresponding to the maximum GMI ratio is different for various frequencies.The positive maximum GMI ratio is 17.2%for Ha=1600A/m and frequency of 3 MHz.In addition,the films display a large negative GMI ratio with a magnetic field applied along the transverse direction and the value of the GMI ratio is about-13.4%for Ha=5600A/m and frequency of 3 MHz.

SnS_2 nanosheets arrays sandwiched by N-doped carbon and TiO_2 for high-performance Na-ion storage

In this paper, SnS_2 nanosheets arrays sandwiched by porous N-doped carbon and TiO_2(TiO_2@SnS_2@N-C) on flexible carbon cloth are prepared and tested as a free-standing anode for high-performance sodium ion batteries. The as-obtained TiO_2@SnS_2@N-C composite delivers a remarkable capacity performance(840 mA h g^(-1) at a current density of 200 mA g^(-1)), excellent rate capability and long-cycling life stability(293 mA h g^(-1) at 1 A g^(-1) after 600 cycles). The excellent electrochemical performance can be attributed to the synergistic effect of each component of the unique hybrid structure, in which the SnS_2 nanosheets with open framworks offer high capacity, while the porous N-doped carbon nanoplates arrays on flexible carbon cloth are able to improve the conductivity and the TiO_2 passivation layer can keep the structure integrity of SnS_2 nanosheets.

Giant Magnetoimpedance Effect in a Sandwiched Structure of as-Quenched FeNiCrSiB Ribbons

The giant magnetoimpedance(GMI)effect and effective permeability ratio in a QFR/Cu/QFR sandwiched structure are studied,where QFR stands for the as-quenched FeNiCrSiB amorphous ribbon.Remarkable GMI effects are obtained in the QFR/Cu/QFR sandwiched structure without annealing.The maximum values of the longitudinal and transverse GMI ratios at 0.5 MHz are 282%and 408%,respectively.Correspondingly,the maximum effective permeability ratios at 0.5 MHz are 326%and 1013%in longitudinal and transverse field,respectively.These large GMI values are attributed to the high effective permeability of the sample due to the closed alternating current(ac)magnetic flux path in the sandwiched structure,and large permeability variation induced by the magnetic field.

Output Characteristics of n-Buried-pSOI Sandwiched RF Power LDMOS

A novel n-buried-pSOI sandwiched structure for an RF power LDMOS is proposed. The output characteristics of the RF power LDMOS are greatly affected by the drain-substrate parasitic capacitance. The output characteristics become better as the drain-substrate parasitic capacitance decreases. Results show that the drain-substrate capacitance of the n- buried-pSOI sandwiched LDMOS is 46.6% less than that of the normal LDMOS,and 11.5% less than that of the n-buried- pSOI LDMOS,respectively. At l dB compression point,its output power is 188% higher than that of the normal LDMOS, and 10.6% higher than that of the n-buried-pSOI LDMOS, respectively. The power-added efficiency of the proposed structure is 38.3%. The breakdown voltage of the proposed structure is 11% more than that of the normal LDMOS.