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Collective Bands in the Neutron—Rich 110Ru Nucleus

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Chinese Physics Letters 2003年第3期20卷 350-353页

作者：姜卓 j.h.hamilton 等 DepartmentofPhysics TsinghuaUniversityBeijing100084 DepartmentofPhysics VanderbiltUniversityNashvilleTN37235USA

high spin states in neutron-rich 110Ru nucleus have been investigated by measuring high-fold prompt γ-ray coincidence events of the spontaneous fission of 252Cf with the Gammasphere detector array. The ground-state band and the γ-vibrational band have been confirmed and extended with spin up to 18 and 13 , respectively. The other three side bands, two proposed as two-quasiparticle bands and one proposed as a four-quasiparticle band, have been observed for the first time. The possible configurations for the quasi-particle bands are discussed. The cranked shell model calculations show that 110Ru nucleus may have oblate triaxial deformation with parameters β2 = -0.30 and γ = 24°, and the band crossing in the yrast band is due to the alignment of a pair of h11/2 neutrons.

关键词： Gamma rays

Analysis of the geometrical dependence of auxetic behavior in reentrant structures by finite elements

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Acta Mechanica Sinica 2016年第2期32卷 295-300页

作者： V.h.Carneiro h.Puga j.Meireles Department of Mechanical Engineering University of Minho

Materials with a negative Poisson＇s ratio（PR）are called auxetics;they are characterized by expansion/contraction when tensioned/*** this counterintuitive behavior,they present very particular characteristics and mechanical *** models have been developed to justify and artificiall reproduce such materials＇ auxetic *** focus of this study is the exploration of a reentrant model by analyzing the variation in the PR of reentrant structures as a function of geometrical and base material *** is shown that,even in the presence of protruding ribs,there may not be auxetic behavior,and this depends on the geometry of each reentrant *** determined for these parameters can be helpful as approximate reference data in the design and fabrication of auxetic lattices using reentrant geometries.

关键词： Auxetic Poisson’s ratio Reentrant Finite element analysis Elasticity

EXPERIMENTAL RESEARCh OF CYLINDER TO BED hEAT TRANSFER IN AGITATED FLUIDIZED BEDS

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journal of hydrodynamics 2000年第4期12卷 36-40页

作者： Ma, j.h. Dep. of Air-condition Eng. Shandong Inst. of Archit. and Eng. Jinan 250014 China

Cylinder-to-bed heat transfer in agitated fluidized beds was studied experimentally. In the experiments, the aluminum particles were used as bed material, the diameter of those ranged from 0.5 mm to 2 mm. The effects of gas velocity, particles size, and agitator rotary speed on heat transfer were studied. From the experimental results, we have come to the following conclusion: (1) there are optimal ranges for airflow velocity and rotary speed to get optimal heat transfer coefficient; (2) the cylinder-to-bed heat transfer is greatly affected by gas velocity, rotary speed and particles sizes, and the effect of rotary speed on heat transfer is similar to that of gas velocity; (3) higher heat transfer coefficient is obtained with smaller particles.

关键词： Fluidized beds heat transfer Mass transfer Two phase flow

Development of mathematical model with a genetic algorithm for automatic arc welding process

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Acta Metallurgica Sinica(English Letters) 2010年第3期23卷 230-240页

作者： D.T.Thao I.S.Kim j.W.jeong j.h.Lee j.Y.Shim h.h.Kim Department of Mechanical Engineering Mokpo National University

This paper is to represent new algorithms to predict process parameters on top-bead width in robotic gas metal arc（GMA） welding *** models have been developed：linear, curvilinear and intelligent model based on full factorial design with two *** analysis was employed for optimization of the coefficients of linear and curvilinear models, while genetic algorithm（GA） was utilized to estimate the coefficients of an intelligent *** only the fitting of these models were checked and compared by using a variance test（ANOVA）, but also the prediction on top-bead width using the developed models were carried out based on the additional *** developed models were employed to investigate the characteristic between process parameters and top-bead *** solutions and graphical representation showed that the intelligent model developed can be employed for prediction of bead geometry in GMA welding process.

关键词： Top-bead width Genetic algorithm Multiple regression Robotic arc welding GMA welding

Design of logic process based low-power 512-bit EEPROM for UhF RFID tag chip

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journal of Central South University 2010年第5期17卷 1011-1020页

作者：金丽妍 LEE j.h KIM Y h Department of Electronic Engineering Changwon National University

A 512-bit EEPROM IP was designed by using just logic process based *** limit the voltages of the devices within 5.5 V,EEPROM core circuits,control gate(CG) and tunnel gate(TG) driving circuits,DC-DC converters:positive pumping voltage(VPP=4.75 V) ,negative pumping voltage(VNN=4.75 V) ,and VNNL(=VNN/2) generation circuit were *** addition,switching powers CG high voltage(CG_hV) ,CG low voltage(CG_LV) ,TG high voltage(TG_hV) ,TG low voltage(TG_LV) ,VNNL_CG and VNNL_TG switching circuit were supplied for the CG and TG driving ***,a sequential pumping scheme and a new ring oscillator with a dual oscillation period were *** reduce a power consumption of EEPROM in the write mode,the reference voltages VREF_VPP for VPP and VREE_VNN for VNN were used by dividing VDD(1.2 V) supply voltage supplied from the analog block in stead of removing the reference voltage generators.A voltage level detector using a capacitive divider as a low-power DC-DC converter design technique was *** result shows that the power dissipation is 0.34μW in the read mode,13.76μW in the program mode,and 13.66μW in the erase mode.

关键词： electrically erasable programmable read-only memory (EEPROM) logic process DC-DC converter ring oscillator sequential pumping scheme dual oscillation period radio frequency identification (RFID)

s-REGULAR DIhEDRAL COVERINGS OF ThE COMPLETE GRAPh OF ORDER 4

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Chinese Annals of Mathematics,Series B 2004年第1期25卷 57-64页

作者： FENGYANQUAN j.h.KWAK DepartmentofMathematics NorthernJiaotongUniversityBeijing100044China CombinatorialandComputationalMathematicsCenter PohangUniversityofScienceandTechnologyPohang790-784Korea.

A graph is s-regular if its automorphism group acts regularly on the set of its s-arcs. An infinite family of cubic 1-regular graphs was constructed in [7] as cyclic coverings of the three-dimensional hypercube, and a classification of all s-regular cyclic coverings of the complete bipartite graph of order 6 was given in [8] for each s ≥ 1, whose fibre-preserving automorphism subgroups act arc-transitively. In this paper, the authors classify all s-regular dihedral coverings of the complete graph of order 4 for each s ≥ 1, whose fibre-preserving automorphism subgroups act arc-transitively. As a result, a new infinite family of cubic 1-regular graphs is constructed.

关键词： s-regular graphs s-arc-transitive graphs Regular coverings

COMPOSITION OPERATORS ON BERGMAN SPACES

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Chinese Annals of Mathematics,Series B 2003年第4期24卷 433-448页

作者： j.h.CLIFFORD ZhENGDEChAO DepaxtmentofMathematicsandStatistics UniversityofMichiganatDearbornDearbornMichigan48128USA DepartmentofMathematics VanderbiltUniversityNashvilleTN37240USA.

The authors obtain function theoretic characterizations of the compactness on the standardweighted Bergman spaces of the two operators formed by multiplying a composition operatorwith the adjoint of another compositio... 详细信息

关键词： Bergman spaces Composition operator

Composition and size dependent torsion fracture of metallic glasses

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journal of Materials Science & Technology 2021年第23期82卷 153-160页

作者： j.Dong j.Shen Y.h.Sun h.B.Ke B.A.Sun W.h.Wang h.Y.Bai Institute of Physics Chinese Academy of SciencesBeijing100190PR China College of Materials Science and Opto Electronic Technology University of Chinese Academy of SciencesBeijing100049PR China Songshan Lake Materials Laboratory DongguanGuangdong523808PR China

The fracture of metallic glasses(MGs)of different compositions and sizes down to micrometers under torsion loading were systematically *** to the flat shear fracture along the circumferential plane as commonly supposed under torsion,we find that the torsion fracture of metallic glasses can deviate from flat shear plane,and the fracture angle is closely dependent on the composition and the size of MG *** a conversion method,we show that the torsion fracture of both millimeterand micrometer-sized MGs can be described by the ellipse fracture criterion as originally proposed for the tension *** deviation from the circumferential shear plane under torsion is further shown to intrinsically relate to the fracture toughness of *** tougher MG tends to have a smaller fracture angle with respect to the maximum shear plane,and vice versa,indicating a correlation between the fracture toughness and pressure/normal stress sensitivity in *** results provide new insights on the fracture mechanism and are helpful to design and control the deformation and fracture behavior of MGs under torsion loading.

关键词： Metallic glasses Torsion fracture Pressure sensitivity Fracture toughness

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螺母如何上紧

石油化工设备 1974年第5期 77-80页

作者： william ,j.h ,Vossbrinck

过去上紧螺栓连接的法兰,用冲击式和猛击式扳手(Impact and sloggingwrencbcs)就行了。用这种方法紧螺母,可以随意紧,也可以按一定程序紧,并在通过水压试验后投入运转,没啥问题;后来虽有泄漏,关系也不大。但现今强调节约自然资源,减少... 详细信息

过去上紧螺栓连接的法兰,用冲击式和猛击式扳手(Impact and sloggingwrencbcs)就行了。用这种方法紧螺母,可以随意紧,也可以按一定程序紧,并在通过水压试验后投入运转,没啥问题;后来虽有泄漏,关系也不大。但现今强调节约自然资源,减少有毒和易爆气体的危险性泄漏、改善环境和提高设备效率,这些漏失必须消除。

关键词：螺母法兰旋转角螺帽紧固件凸缘联结件拉紧装置扭矩扳手