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This report derives the exact solutions for the problem of a magneto-electro-elastic cylinder with a penny-shaped and embedded crack subjected to transient thermal load. Thermal cracking is analysed in the theoretical framework of linear magneto-electro-thermo-elasticity. The heat conduction equation for a magneto-electro-thermo-elastic cylinder with a finite size is solved using the standard method of separation variables. The coupling magneto-electro-thermo-elastic fields are determined in a stationary case via the Hankel integral transform. Based on Abel’s integral equation and the dual integral equation, the mathematical formulations for the permeable crack conditions are derived. Solutions to the elastic, electric, and magnetic intensity factors are obtained. Due to the explicitness of these solutions, they are very interesting for the design and analysis of magneto-electro-thermo-elastic composites.

To overcome the defect that the support pressure is required to be measured or supposed in elasto-plastic analysis in strain-softening rock mass, by the connection of the support pressure imposed on surrounding rock mass, without assuming the support pressure is known a priori, an improved model of solving plastic radius and the distribution of radial displacement around the circular tunnel is proposed. Based on Hoek-Brown yield criterion, the results obtained by strain-softening model are compared with those of elastic perfectly brittle and elastic perfectly plastic models. The examples reveal that the difference of plastic radius obtained by the three models is comparatively smaller, but the difference of radial displacement is comparatively larger. The proposed model overcomes some defects of the previous studies in deformation analysis for tunnel.

Accurate evaluation of the thermal shock resistance is great importance when estimating both the life and the performance of piezoelectric structures under thermal shock load. Non-Fourier heat conduction law assumed that the speed of heat propagation in a body is finite, which is more exact to evaluate the thermal shock resistance when the thermal shock time reduces to ps/fs scale or the length size of materials reduces to micro/nanoscale. A hyperbolic heat conduction equation was used to study the thermal shock resistance of a cylindrical piezoelectric structure, in which a permeable penny-shaped crack is considered. The analytical solution of non-Fourier temperature filed is determined by the method of separated variable. The formulas of the associating thermal stress and electrical displacement in the piezoelectric cylinder without crack were obtained. The crack problem is solved by the Dual integral equation and Abel integral equation. The thermal shock resistance is evaluated by associating the stress-based and fracture mechanics-based failure criteria.

Two new lanostane triterpenoid acids, 12β, 15α-dihydroxy-24-methyl-3,23-dioxo-lanosta-7,9(11)-dien-26-oic acid (1), and 3α, 12β-dihydroxy-24-methyl-7,23-dioxo-lanosta-8-en-26-oic acid (2), were isolated from the methanolic extract of Uighur medicine Fomes officinalis. Their structures were elucidated based on the analysis of spectroscopic data (1D, 2D NMR and HR-MS). Anti-inflammatory and cytotoxicity assays revealed that both compound 1 and 2 show no inhibitory effects on nitric oxide production in lipopolysaccharide-induced RAW264.7 cells, and no cytotoxicity activities against HepG2 cells.

Use FLAC3D, the interface command to define joint surface, set up rock mass models with 15 °, 30 °, 60 °, etc. different dip joint, and in accordance with the laboratory test data of rock and joint surface for a variety of strength and deformation parameters setting, carries on the numerical simulation of uniaxial compression. Got failure mode, plastic zone evolution and the stress strain curve of rock mass with different dip joint, and the result compared with the actual test has a higher similarity, to prove the feasibility of the numerical simulation method.

The relationship between the peak strength of rock masses and joint inclination angle is closely, to study its relationship, experiment on pre-existing persistent jointed rock cylindrical standard specimens was made under uniaxial compression by high stiffness servo control testing machine, experiment found that: the residual peak intensity and peak strength are increased with the decrease of jointed and nonlinear. Analysis on the peak intensity changing with the fissure inclination using Kulun strength theory, theory analysis conclusion is consistent with the experiment, prove the conclusions of experiments and theoretical analysis all can reflect the law of rock masses with transfixion joint failure strength well.

A simple numerical procedure of strain-softening model for the elasto-plastic analysis of a circular opening is presented by modifying the procedure proposed by Lee and Pietruszczak (2008) . The proposed procedure has two advantages over that of Lee and Pietruszczak (2008) . One is that the elasto-plastic coupling can be considered, the other is that the equilibrium equation and compatibility equation need not be expressed with respect to the normalized radius. Through MATLAB programming, the accuracy and validity of the proposed procedure are demonstrated through some examples. The influence of elastic modulus and Poisson’s ratio evolution on the distribution of radial displacement and hoop stress, ground response curve (GRC) and plastic radius was investigated, and the results show that, with the decrease of elastic modulus evolutional ratio, the radial displacement, hoop stress and plastic radius all increase. With the increase of Poisson’s ratio evolutional ratio, the radial displacement, hoop stress and plastic radius all decrease. As for influence extent, the evolution of elastic modulus has great influence on the radial displacement; and the evolution of Poisson’s ratio has smaller influence on the radial displacement, both of them have very slight influence on the hoop stress near the excavation face but greater on the hoop stress near the interface of elastic and plastic region. And both of them have very slight influence on the plastic radius.

Zearalenone (ZEN) exerts a major effect on human and animal health and has led to serious worldwide economic problems. In this study, we investigated whether proanthocyanidin (PC) can prevent ZEN-induced testicular oxidative damage in male mice and explored the underlying mechanism. Kunming mice were injected with ZEN (40 mg kg-1) on the 11th day after intragastric administration of PC (75 or 150 mg/kg) for 10 days; the sperm quality of mice was then analysed statistically. Additionally, testicular morphology parameters related to oxidative damage, apoptosis and the expression of endoplasmic reticulum (ER) stress-related genes (GRP78, CHOP and XBP-1) were all measured. Results showed that ZEN exposure significantly reduced the sperm density, improved the sperm aberration rate, increased the MDA level and reduced SOD and GSH-Px activities. Meanwhile, ZEN was attributed to the downregulation of the expressions of the gene and protein of Bcl-2 and upregulation of the expressions of the gene and protein of Bax and caspase-3. ZEN exposure also upregulated the mRNA expression of GRP78, CHOP and XBP-1; however, PC pre-treatment reduced ZEN-induced oxidative damage and tended to maintain normal testicular morphology. Furthermore, PC pre-treatment substantially downregulated the expressions of the GRP78, CHOP and XBP-1 and upregulated the expression of the Bcl-2 gene. In conclusion, PC, due to its anti-oxidative ability, could ameliorate ZEN-induced testicular reproductive toxicity in male mice by decreasing ER stress and testicular cell apoptosis.

In order to predict the stability of surrounding rock mass in geotechnical engineering, it is important to study the post-failure deformation property and residual strength of rock mass. Based on evolutional behavior of strength parameters, aiming at generalized Hoek-Brown strength criterion, selecting major principal strain as strain softening parameter, this paper presents the method of solving post-failure stress-strain curve . In numerical case, the effect of evolutional law of strength parameters ， and to deformation and residual strength is discussed and we can draw the following conclusions: the greater the residual values of ， are and the smaller the residual value of is, the post-failure strain softening curve falls more gently and the greater the residual strength is.

We report the 87Sr optical lattice clock developed at the National Time Service Center. We achieved a closed-loop operation of the optical lattice clock based on 87Sr atoms. The linewidth of the spin-polarized clock peak is 3.9 Hz with a clock laser pulse length of 300 ms, which corresponds to a Fourier-limited linewidth of 3 Hz. The fitting of the in-loop error signal data shows that the instability is approximately , affected primarily by the white noise. The fractional frequency difference averages down to for an averaging time of 3000 s.