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Thermo-mechanical properties of bowl-shaped grinding wheel and machining error compensation for grinding indexable inserts

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Journal of Central South University 2015年第10期22卷 3830-3836页

作者：张祥雷姚斌陈彬强孙维方王萌萌罗琪 Department of mechanical and Electrical engineering School of Physics and Mechanical & Electrical EngineeringXiamen University

In order to meet the technical requirements of grinding the circumferential cutting edge of indexable inserts, thermo-mechanical properties of bowl-shaped grinding wheel in high speed grinding process and the influence of dimension variations of the grinding wheel on machining accuracy were investigated. Firstly, the variation trends of the dimension due to centrifugal force generated in different wheel speeds were studied and the effect of stress stiffening and spin softening was presented. Triangular heat flux distribution model was adopted to determine temperature distribution in grinding process. Temperature field cloud pictures were obtained by the finite element software. Then, dimension variation trends of wheel structure were acquired by considering the thermo-mechanical characteristic under combined action of centrifugal force and grinding heat at different speeds. A method of online dynamic monitoring and automatic compensation for dimension error of indexable insert was proposed. By experimental verification, the precision of the inserts satisfies the requirement of processing.

关键词： bowl-shaped grinding wheel thermo-mechanical properties indexable insert machining accuracy compensation

Balmer-alpha and Balmer-beta Stark line intensity profiles for high-power hydrogen inductively coupled plasmas

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Chinese physics B 2014年第7期23卷 499-504页

作者：王松柏雷光玖刘东平杨思泽 School of physics and mechanical&Electrical engineering Xiamen University College of physics and Information engineering Fuzhou University Southwestern Institute of physics School of physics and mechanical & Electrical engineering Xiamen University

We compare Balmer-alpha （Ha） and Balmer-beta （Hβ） emissions from high-power （1.0-6.0 kW） hydrogen inductively coupled plasmas （ICPs）, and propose region Ⅰ （0.0-2.0 kW）, region Ⅱ （2.0-5.0 kW）, and region Ⅲ （5.0-6.0 kW）. In region Ⅰ, both Ha emission intensity （la） and Hβ emission intensity （1β） increase with radio frequency （RF） power, which is explained by the corona model and Boltzmann＇s law, etc. However, in region II, la almost remains constant while 1β rapidly achieves its maximum value. In region Ⅲ, 1α slightly increases with RF power, while 1β decreases with RF power, which deviates significantly from the theoretical explanation for the Ha and Hβ emissions in region I. It is suggested that two strong electric fields are generated in high-power （2.0-6.0 kW） hydrogen ICPs： one is due to the external electric field of high-power RF discharge, and the other one is due to the micro electric field of the ions and electrons around the exited state hydrogen atoms in ICPs. Therefore, the strong Stark effect can play an important role in explaining the experimental results.

关键词： high-power radio frequency plasma Hα and Hβ spectral lines in hydrogen ICPs Stark effect

Influence of doping effect on structure and superconducting properties of MgB_2

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中国有色金属学会会刊：英文版 2003年第4期13卷 912-916页

作者：熊玉华李培杰张晓平赵永刚曹必松曾大本 Department of mechanical engineering Department of physics

Mg 1- x M x B 2 (M=Li or deficiency) compounds were prepared and their structure and superconducting properties were studied. The results show that nearly single phased Mg 1- x Li x B 2 samples have been obtained while x ≤0.3. With increasing x , lattice parameters a decreases and c shows no obvious change, and the superconducting transition temperature T c of Mg 1- x Li x B 2 decreases. Moreover, loss of superconductivity occurs for sample with x =0.5. For Mg 1- x B 2 nearly single phased samples can be obtained at x =0. MgB 2 coexists with MgB 4 phase and some minor impurity phases while 0< x <0.5. With the increase of x , a and c of MgB 2 decreases and increases, respectively, and T c decreases. The obvious difference in the superconductivity of Mg 1- x Li x B 2 and Mg 1- x B 2 suggests that Li indeed dopes into the structure of MgB 2.

关键词：二硼化镁掺杂超导电性结构超导体

Normal mode splitting and ground state cooling in a Fabry-Perot optical cavity and transmission line resonator

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Chinese physics B 2011年第12期20卷 249-258页

作者：陈华俊米贤武 College of physics Mechanical and Electrical EngineeringJishou University

Optomechanical dynamics in two systems which are a transmission line resonator and Fabrya-Perot optical cavity via radiation-pressure are investigated by linearized quantum Langevin equation. We work in the resolved sideband regime where the oscillator resonance frequency exceeds the cavity linewidth. Normal mode splittings of the mechanical resonator as a pure result of the coupling interaction in the two optomechanical systems is studied, and we make a comparison of normal mode splitting of mechanical resonator between the two systems. In the optical cavity, the normal mode splitting of the movable mirror approaches the latest experiment very well. In addition, an approximation scheme is introduced to demonstrate the ground state cooling, and we make a comparison of cooling between the two systems dominated by two key factors, which are the initial bath temperature and the mechanical quality factor. Since both the normal mode splitting and cooling require working in the resolved sideband regime, whether the normal mode splitting influences the cooling of the mirror is considered. Considering the size of the mechanical resonator and precooling the system, the mechanical resonator in the transmission line resonator system is easier to achieve the ground state cooling than in optical cavity.

关键词： optomechanical system normal mode splitting ground state cooling

Quantum dynamic behaviour in a coupled cavities system

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Chinese physics B 2012年第6期21卷 26-32页

作者：彭俊邬云文李小娟 College of physics Mechanical and Electrical EngineeringJishou University

The dynamic behaviour of the two-site coupled cavities model which is doped with ta wo-level system is investi-gated. The exact dynamic solutions in the general condition are obtained via Laplace transform. The simple analytical solutions are obtained in several particular cases, which demonstrate the clear and simple physical picture for the quan-tum state transition of the system. In the large detuning or hoppling case, the quantum states transferring between qubits follow a slow periodic oscillation induced by the very weak excitation of the cavity mode. In the large coupling case, the system can be interpreted as two Jaynes-Cummings model subsystems which interact through photon hop between the two cavities. In the case of λ≈△〉〉 g, the quantum states transition of qubits is accompanied by the excitation of the cavity, and the cavity modes have the same dynamic behaviours and the amplitude of probability is equM to 0.25 which does not change with the variation of parameter.

关键词： coupled cavities quantum dynamics behaviour detuning two-level system

Position-dependent property of resonant dipole-dipole interaction mediated by localized surface plasmon of an Ag nanosphere

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Chinese physics B 2015年第2期24卷 158-164页

作者：许丹王小云黄勇刚欧阳仕粮何海龙何浩 College of physics Mechanical and Electrical EngineeringJishou University

We use the photon Green-function method to study the quantum resonant dipole-dipole interaction（RDDI） induced by an Ag nanosphere（ANP）.As the distance between the two dipoles increases,the RDDI becomes weaker,which is accompanied by the influence of the higher-order mode of the ANP on RDDI declining more quickly than that of the dipole *** a broad frequency range（above 0.05 eV）,the transfer rate of the RDDI is nearly constant since the two dipoles are fixed at the proper *** addition,this phenomenon still exists for slightly different radius of the *** find that the frequency corresponding to the maximum transfer rate of RDDI exhibits a monotonic decrease by moving away one dipole as the other dipole and the ANP are kept *** addition,the radius of ANP has little effect on *** the two dipoles are far from the ANP,the maximum transfer rate of the RDDI takes place at the frequency of the dipole *** contrast,when the two dipoles are close to the ANP,the higher-order modes come into effect and they will play a leading role in the RDDI if they match the transition frequency of the *** results may be used in a biological detector and have a certain guiding significance for further application.

关键词： quantum resonant dipole-dipole interaction photonic Green function surface plasmon

Optomechanical entanglement in a whispering-gallery cavity

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Chinese physics B 2012年第3期21卷 45-50页

作者：米贤武柏江湘李德俊 College of physics and mechanical & Electrical engineering Jishou University

The dynamics of the optomechanical entanglement between optical cavity field modes and a macroscopic me- chanical breathing mode in a whispering-gallery cavity as well as the continuous variable entanglement between the phase-quadrature amplitudes of the two whispering-gallery modes have been analysed. Simulated results indicate that under state-of-the^art experimental conditions, optomechanical entanglement is obvious and can occur even at temper- atures of above 40 K. Compared with the entanglement of the mechanical oscillator at the ground state temperature, optomechanical entanglement is more intense by several orders of magnitude.

关键词： optomechanical entanglement whispering-gallery mode

Quantum correlation dynamics of three non-coupled two-level atoms in different reservoirs

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Chinese physics B 2013年第2期22卷 109-114页

作者：王小云丁邦福赵鹤平 College of physics and mechanical & Electrical engineering Jishou University

Time evolution dynamics of three non-coupled two-level atoms independently interacting with their reservoirs is solved exactly by considering a damping Lorentzian spectral *** three atoms initially prepared in Greenberger-Horne-Zeilinger-type state,quantum correlation dynamics in a Markovian reservoir is compared with that in a nonMarkovian *** increasing detuning quantity in the non-Markovian reservoir,three-atom correlation dynamics measured by negative eigenvalue presents a trapping phenomenon which provides long-time quantum *** we compare the correlation dynamics of three atoms with that of two atoms,measured by quantum entanglement and quantum discord for an initial robuster-entangled type *** result further confirms that quantum discord is indeed different from quantum entanglement in identifying quantum correlation of many bodies.

关键词： quantum correlation dynamics Lorentzian spectral density Markovian and non-Markovian reservoirs

Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 528-547页

作者： Jiaolong Liu Siyu Zhang Dan Qu Xuejiao Zhou Moxuan Yin Chenxuan Wang Xuelin Zhang Sichen Li Peijun Zhang Yuqi Zhou Kai Tao Mengyang Li Bing Wei Hongjing Wu Mengyang Li Bing Wei Hongjing Wu School of physics Xidian UniversityXi’an 710071People’s Republic of China School of Advanced Materials and Nanotechnology State Key Discipline Laboratory of Wide Band Gap Semiconductor TechnologyXidian UniversityXi’an 710071People’s Republic of China School of Microelectronics Xidian UniversityXi’an 710071People’s Republic of China School of Telecommunication engineering Xidian UniversityXi’an 710071People’s Republic of China MOE Key Laboratory of Material physics and Chemistry Under Extraordinary School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China The Ministry of Education Key Laboratory of Micro and Nano Systems forAerospace School of Mechanical EngineeringNorthwestern PolytechnicalUniversityXi’an 710072People’s Republic of China

Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic *** methods,however,constrain their delicate ***,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon *** unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial ***“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first ***,the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric *** defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response.

关键词： Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption