Oxidation Behaviour of the Matrix Materials in Spherical Fuel Elements

The oxidation resistance of the matrix materials is vital to the normal operation of HTGR and is also an important parameter for evaluating the safety response under accidental air or water ingress conditions. The oxidation kinetics of the three matrix material components: natural graphite, artificial graphite and resin carbon. was studied in a flowing gas mixture of oxygen and nitrogen using an auto thermogravimetric system. The results indicate that the artificial graphite has the slowest oxidation rate followed by the natural graphite and then the resin carbon with the highest oxidation rate. Vacuum heat treatment of the natural graphite at 1950℃ decreases the impurities and increases the oxidation activation energy. Differences between the activation energy and the oxidation rate of the resin carbon heat treated at 1950℃ and 1600℃ resulted from changes in the micro-pore texture. and the reduction of impurities.

Performance of the Cement Matrix Composite Material With Rubber Powder

The effect of the deferent rubber content substituted for fine aggregate on the mortar performance was studied.The effects of the rubber coated with the coating materials on the mortar compressive strength,bending strength and impact work were discussed.The optimum rubber powder content and the suitable coating material were found.Through the electrical probe test-BEI,SEI and calcium ion distribution,and the slight crack and the interface between the rubber and cement matrix are analyzed.The results show that the rubber powder coated with the surface treatment materials A,B and C has the capability of absorbing a large amount of energy under the compressive and flexural load and the slight cracks of R-C were controlled and restrained.

TGF-beta 1 Gene-Activated Matrices Regulated the Osteogenic Differentiation of BMSCs

Poly （lactic acid/glycolic acid/asparagic acid-co-polyethylene glycol）（PLGA-[ASP-PEG]） scaffold materials were linked with a novel nonviral vector （K）16GRGDSPC through cross linker Sulfo- LC-SPDP to construct a new type of nonviral gene transfer system. Eukaryotic expressing vector containing transforming growth factor beta 1 （pcDNA3-TGFβ1） was encapsulated by the system. Bone marrow stromal cells （BMSCs） obtained from rabbit were cultured on PLGA-[ASP-PEG] modified by （K）16GRGDSPC and TGF-β1 gene and PLGA-[ASP-PEG] modified by （K）16GRGDSPC and empty vector pcDNA3 as control. The expressions of osteogenic makers of the BMSCs cultured on the TGF-β1 gene-activated scaffold materials were found significantly higher than those of the control group （P〈0.05）. A brand-new way was provided for regulating seed cells to directionally differentiate into osteoblasts for bone defect restoration in bone tissue engineering.

Propagation of rotating elliptical Gaussian beams from right-handed material to left-handed material

By applying the ABCD matrix method, we report the propagating properties of the rotating elliptical Gaussian beams（REGBs） from the right-handed material（RHM） to the left-handed material（LHM）. Based on the propagation equation, we obtain the intensity distributions of the REGBs during the propagation. It is found that the rotating direction of the REGBs is opposite in the RHM and the LHM, and the rotation angles tend to be π /2 as the propagation distance is long enough.Then we analyze the relationship between the refractive index and the rotating velocity. Furthermore, the energy flow and the angular momentum（AM） of the REGBs which can rotate are also obtained.

An all-optical matrix multiplication scheme with non-linear material based switching system

Optics is a potential candidate in information, data, and image processing. In all-optical data and information processing, optics has been used as information carrying signal because of its inherent advantages of parallelism. Several optical methods are proposed in support of the above processing. In many algebraic, arithmetic, and image processing schemes fundamental logic and memory operations are conducted exploring all-optical devices. In this communication we report an all-optical matrix multiplication operation with non-linear material based switching circuit.

Damping of Ni–Mn–Ga epoxy resin composites

By combining the advantages of effcient damping and high mechanical properties,Ni-Mn-Ga particle composites have a very good prospect for applications in damping structure design.In this paper,a ferromagnetic shape memory alloy Ni-Mn-Ga composite is prepared.Ni-Mn-Ga particle/bisphenol-A epoxy composite cantilever beam vibration tests under a magnetic feld and without the magnetic feld are conducted to analyze the structural damping ratios n.Meanwhile,the damping characteristics of the Ni-Mn-Ga composite are studied through the axial loading-unloading method and the acoustic emission signals method.The damping coeffcient of the composite for different Ni-Mn-Ga volume fractions is obtained.The interface properties of the composite are discussed by micro examination and axial loading.The relationships between the damping of the composite and that of the component materials are discussed.The specifc damping capacity（SDC）and acoustic emission counts diagram of different specimens with different Ni-Mn-Ga volume fractions are analyzed.

Static response of a layered magneto-electro-elastic half-space structure under circular surface loading

A cylindrical system of vector functions, the stiffness matrix method and the corresponding recursive algorithm are proposed to investigate the static response of transversely isotropic,layered magneto-electro-elastic（MEE） structures over a homogeneous half-space substrate subjected to circular surface loading. In terms of the system of vector functions, we expand the extended displacements and stresses, and deduce two sets of ordinary differential equations, which are related to the expansion coeficients. The solution to one of the two sets of these ordinary differential equations can be evaluated by using the stiffness matrix method and the corresponding recursive algorithm. These expansion coeficients are then integrated by adaptive Gaussian quadrature to obtain the displacements and stresses in the physical domain. Two types of surface loads, mechanical pressure and electric loading,are considered in the numerical examples. The calculated results show that the proposed technique is stable and effective in analyzing the layered half-space MEE structures under surface loading.