Radiation pasteurised oil palm empty fruit bunch fermented with Pleurotus sajor-caju as feed supplement to ruminants

In solid state fermentation, Pleurotus sajor-caju has been found to be able to degrade at least 30% oil palm empty Fruit Bunch (EFB) fibre leaving 70 % useful materials. Conditions under which fermentation carried out were investigated. It was found that, in the temperature range between 25– 28 °C, relative ph between 6–8, moisture between 60–70 % and medium composition of CaCO₃: rice bran 2 %: 5 % were the optimum conditions. The results showed in fermented products that, there were substantial reduction in cellulosic component such as Crude Fiber (CF, 18 %); Acid Detergent Fibre (ADF, 45 %), Neutral Detergent Fibre (NDF, 61 %) and Acid Detergent Lignin (ADL, 14 %). However, Crude Protein (CP, 10%) increased resulted from single cell protein enrichment of mycelial microbial mass. The mass reductions of substrate in fermentation process corresponds to the CO₂ released during fermentation. Hence, attributable to the decreased in content of CF, ADF, NDF, and ADL. The digestibility study has also been carried out to determine the useful level of this product to ruminant. Aflatoxin content was detected low in both the initial substrates and products. Based on nutritional value and low content of aflatoxin, the product is useful as a source of roughage to ruminant.     

A molecular network model to describe the nonlinear viscoelastic behavior of polymers

A transient molecular network model is built to describe the nonlinear viscoelasticity of polymers by considering the effect of entanglement loss and regeneration on the relaxation of molecular strands. It is an extension of previous network theories. The experimental data on three thermoplastic polymers (ABS, PVC and PA6) obtained under various loading conditions are used to test the model. Agreement between the theoretical and experimental curves shows that the suggested model can describe successfully the relaxation behavior of the thermoplastic polymers under different loading rates by using relatively few relaxation modes. Thus the micromechanism responsible for strain-rate dependence of relaxation process and the origin of nonlinear viscoelasticity may be disclosed. The project supported by the National Natural Science Foundation of China and Doctorial Fund     

延长速调管使用寿命的方法

描述了一种延长EPR波谱仪中速调管使用寿命的方法.根据这种方法,只要正确地调谐微波桥的工作状态和适当地调整功率电平器的功率校正电平.即使对于已经严重老化的速调管仍然可以继续使用一段时间,维持仪器的正常运行.     

A diffusion approximation result for two parameter processes

Summary We consider a one-dimensional linear wave equation with a small mean zero dissipative field and with the boundary condition imposed by the so-called Goursat problem. In order to observe the effect of the randomness on the solution we perform a space-time rescaling and we rewrite the problem in a diffusion approximation form for two parameter processes. We prove that the solution converges in distribution toward the solution of a two-parameter stochastic differential equation which we identify. The diffusion approximation results for oneparameter processes are well known and well understood. In fact, the solution of the one-parameter analog of the problem we consider here is immediate. Unfortunately, the situation is much more complicated for two-parameter processes and we believe that our result is the first one of its kind.Partially supported by ONR N00014-91-J-1010     

Four-wave mixing based 10-Gb/s tunable wavelength conversion in dispersion-flattened microstructure fibers

All-optical wavelength conversion of 10-Gb/s signal based on four-wave mixing is experimentally demonstrated in a 30-m-long dispersion-flattened microstructure fiber with small positive dispersion. For an average pump power of 26 dBm, the conversion efficiency was around -19.5 dB with the fluctuation less than ±1.4 dB, covering a conversion bandwidth of 20 nm. The eye diagram of the converted signal shows good eye opening.     

Multiple periodic solutions of a delayed stage-structured predator–prey model with non-monotone functional responses

A delayed stage-structured predator–prey model with non-monotone functional responses is proposed. It is assumed that immature individuals and mature individuals of the predator are divided by a fixed age, and that immature predators do not have the ability to attack prey. Some new and interesting sufficient conditions are obtained for the global existence of multiple positive periodic solutions of the stage-structured predator–prey model. Our method is based on Mawhin’s coincidence degree and novel estimation techniques for the a priori bounds of unknown solutions to Lx = λNx. An example is given to illustrate the feasibility of our main result.     

Annealing and measurement temperature dependence of W2B5-based rectifying contacts to n-GaN

The thermal stability and measurement temperature dependence of Schottky contact characteristics on n-GaN using a W₂B₅/Ti/Au metallization scheme was studied using current-voltage (I-V), scanning electron microscopy (SEM) and Auger electron spectroscopy (AES) measurements. The elemental profile obtained from samples annealed at 350 °C showed some titanium diffusion into the gold layer but little other difference from the as-deposited wafer. Annealing at 700 °C produced significant diffusion of titanium. The Schottky barrier height increased with anneal temperature up to 200 °C, reaching a maximum value of 0.65 eV, but decreased at higher annealing temperatures. The reverse breakdown voltage from diodes fabricated using the W₂B₅-based contacts showed a similar dependence. The reverse current magnitude was larger than predicted by thermionic emission alone. The barrier height showed only minor changes with measurement temperature up to 150 °C.     

Hydrothermal synthesis of FeS2 for lithium batteries

Nanocrystalline FeS₂ cathode material of lithium cell was synthesized from cheap materials of FeSO₄, Na₂S₂O₃, and sulfur by a hydrothermal process. The scanning electron microscopy analysis showed the obtained material was nano-sized, about 500 nm. The X-ray powder diffraction analysis showed that the synthetic FeS₂ material had two phases of the crystalline structure, pyrite and marcasite. The phase of marcasite seems to have no negative effect on the electrochemical performance of the material. The synthetic FeS₂ showed a significant improvement of electrochemical performance for Li/FeS₂ cells.