Abstract Based on the concept of continuum damage mechanics, an anisotropic damage model for single crystals under the theory of crystal plasticity is presented. Damage and inelastic deformations are incorporated in the proposed model which is developed within the framework of thermodynamics with internal state variables. The dependence of the plastic anisotropy on the damage evolution has been considered. The anisotropic damage is characterized kinematically here through a second‐order damage tensor which is physically based. The proposed model can successfully describe the interaction between the evolution of micro‐structure of single crystals such as lattice orientation and the hardness development of each slip system and the process of material degradation. The Newton–Raphson iterative scheme is used to integrate the constitutive equations that work directly with the evolution equations for the elastic deformation gradient. The consistent algorithmic tangent stiffness for the present algorithm is formulated. The prescribed algorithm together with the consistent algorithmic tangent stiffness has been implemented into the ABAQUS finite element code by using user subroutine. Using the loading processes with homogeneous deformations and simulation of the classical tensile test of a notched bar illustrate the basic aspects of the model described. Numerical simulations show the validation and performance of the present model and algorithm. Copyright © 2004 John Wiley & Sons, Ltd.

Viscoplasticity

Subroutine

Damage mechanics

Tangent modulus

State variable

10.1002/nme.1072

Cite

Citations (11)

Mott insulating states and their quantum phase transitions of interacting spin-3/2 ultracold fermionic atoms on optical lattices

Scientia Sinica(Physica,Mechanica & Astronomica) (2011)

Guang Zhang

We first introduce the ultracold atoms and the optical lattices. Then, we analyze various Mott insulating phases of interacting spin-3/2 fermionic ultracold atoms in two-dimensional square optical lattices. Using a generalized Hubbard model, we identify two distinct symmetry breaking phases: the spin-quadrupole ordering phase and the spin-dipole-spin-octupole ordering phase. Near the SU(4) symmetric point, we find that an algebraic spin liquid phase may emerge due to strong quantum fluctuations. Finally, the possible quantum phase transitions between these exotic phases are also discussed.

Ultracold atom

Quantum phases

Mott insulator

Optical lattice

Source

Cite

Citations (0)

~2.1 um Tm<sup>3+</sup>-Ho<sup>3+</sup> co-doped tungsten tellurite single mode fiber laser

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE (2012)

Kefeng Li Guang Zhang Lili Hu Meng Wang Danping Chen

We investigate the spectroscopic and lasing performance of Tm³⁺-Ho³⁺ co-doped tungsten tellurite single mode fiber operating around 2.1 μm with a commercial 800 nm diode laser pump source. The optimum doping concentration of Tm₂O₃ and Ho₂O₃ in Tm³⁺-Ho³⁺ co-doped TeO₂-WO₃-La₂O₃ (TWL) glass is 1 mol% and 0.5 mol%, respectively. The lifetime of Ho³⁺:⁵I₇ level is 3.3 ms in the bulk glass. The maximum stimulated emission cross-section of Ho³⁺ in TWL is 10.0×10^-21cm². The tungsten tellurite single mode fibers are prepared by using rod-in-tube method. The infrared emission spectra are compared with varying fiber lengths. Tm³⁺-Ho³⁺ co-doped fiber shows weak emission at ~1.9 μm very strong emission at ~2.1 μm, which indicates efficient energy transfer from Tm³⁺ to Ho³⁺ in the fiber. The 1.47 μm emission increases with the increment of the fiber length, which means a back energy transfer from Ho³⁺ to Tm³⁺. A 106 mW continuous wave laser emission at ~2.1 μm is demonstrated from a 16 cm length of this fiber, the slope efficiency is 23%, corresponding to a 17% optical to optical efficiency. Lasing has also been achieved in <5 cm length of this fiber, making this material a promising candidate for single frequency ~2.1 μm laser sources.

10.1117/12.907159

Cite

Citations (2)

Continuous-flow Synthesis of Submicron and Nano-zeolites in Capillary Microchannel Reactor

Journal of Inorganic Materials (2011)

Guang Zhang

Continuous synthesis of NaA and Silicalite-1 submicron and nanoparticles was prepared in a capillary microchannel reactor from clear solutions.The X-ray diffraction(XRD),Transmission Electron Microscope(TEM) and Dynamic Light Scatter(DLS) measurements were used to investigate the effects of different synthesis parameters on the particle size distribution and morphology,including reaction temperature,aging time and residence time.It was indicated that smaller mean particle size and narrower particle size distribution of the products was obtained with lower reaction temperature,longer aging time and shorter residence time during the synthesis process.At the synthesis temperature of 343K,aging time of 72h and residence time of 5.8h,the NaA zeolite crystal with mean particle size of about 100nm was prepared.And at the synthesis temperature of 371K,aging time of 24h and residence time of 10h,the Silicalite-1 zeolite crystal with mean particle size of around 80nm was obtained.The present method offers a novel route for preparing submicro and nano zeolite particles.

Microchannel

Microreactor

Particle (ecology)

Crystal (programming language)

Residence time distribution

Source

Cite

Citations (0)

Durable silicon-carbon composites self-assembled from double-protected heterostructure for lithium-ion batteries

Journal of Colloid and Interface Science (2022)

Xiao Juan Bai Zhang Hui Junpin Lin Guang Zhang

Carbon fibers

Amorphous carbon

10.1016/j.jcis.2022.01.191

Cite

Citations (14)

Production of novel polyhydroxyalkanoates byPseudomonas stutzeri1317 from glucose and soybean oil

FEMS Microbiology Letters (1998)

Wennan He Weidong Tian Guang Zhang Guo‐Qiang Chen Zengming Zhang

A strain of Pseudomonas stutzeri coded 1317 isolated from oil-contaminated soil was found to grow well in glucose and soybean oil as a sole carbon source, respectively. Polyhydroxyalkanoates containing medium chain length monomers of hydroxyalkanoates ranging from C6 to C14 were synthesized up to 52% of cell dry weight of P. stutzri 1317 grown on glucose mineral media. In mineral media containing 10 g l−1 soybean oil, P. stutzeri 1317 produced up to 63% of polyhydroxyalkanoates containing mainly a novel monomer of 3,6-epoxy-7-nonene-1,9 dioic acids making up to 63% of the polyhydroxyalkanoates, together with minor monomers of C8 and C10. 1H- and 13C-nuclear magnetic resonance spectroscopy and electron impact gas chromatography-mass spectroscopy and chemical ionization gas chromatography-mass spectroscopy were used to study the structures of polyhydroxyalkanoates synthesized by P. stutzeri 1317.

Pseudomonas stutzeri

Soybean oil

10.1111/j.1574-6968.1998.tb13297.x

Cite

Citations (91)

Analysis of the relationship between temperature and capacity on sealed valve-regulated lead-acid battery

Diesel Locomotives (2007)

Guang Zhang

The relationship between temperature and capacity on sealed valve-regulated lead-acid battery(VRLA)was investigated and the effect of temperature on the durability of VRLA was analyzed.Points for attention in manufacturing and operate processes of the battery were proposed.

VRLA battery

Battery capacity

Lead (geology)

Source

Cite

Citations (2)