The electron diffraction patterns(EDPS) of Nd1+ϵFe4B4 compounds

The EDPs of Nd_1+ϵFe₄B₄ reveal the variety of the crystal structure. The observations indicate that there exists a quasi-continuous series of compounds near the composition Nd_1.1Fe₄B₄. Such characteristics can be explained in terms of the small energy differences between these phases. The coexistence of different phases in the same bulk sample may be related to local fluctuations of the composition. Clarification of structural details can be expected from more precise electron microscopy studies.     

Optimal (s,S) policies with delivery time guarantees for manufacturing systems with early set-up

We consider optimal (s, S) policies with delivery time guarantees for production planning in one-machine manufacturing systems with early set-up. The machine produces one type of product and delivery time guarantee is offered to the customers for each unit of ordered product. The inter-arrival time of the demand and the processing time for one unit of product are assumed to be exponentially distributed. In a (s, S) policy, the machine will shut down when an inventory level of S is attained and once the inventory level drops to s, the machine will re-start. A set-up time is required for the machine. We model the set-up by the exponential distribution. We obtained an analytical form of the steady state probability distribution for the inventory levels derived. The average profit of the system can be written in terms of this probability distribution. Hence the optimal (s, S) policy can be obtained by varying different possible values of s and S.     

Selectivity of directional correlations of gamma rays from oriented nuclear states at moderately high spins

Calculations are presented for pure-multipole cascades from an aligned initial state of moderately high spin. viz., 10. Pairs of detectors at vertices of an octant in space are used, and the question of selecting a particular assignment of spins and multipolarities from all others is investigated. It is found that for representative conditions of degree of alignment of initial state and quality of data, most of the cascades composed of combinations of dipole, quadrupole and octupole transitions can be distinguished from each other, even including in many cases the order of nonbasic transitions. The number of different cascades considered is 49. Also considered are cases simulating ultrahigh-precision data in order to illustrate principles, as well as quite low-precision data. Considered too, are cases of no alignment of initial spin, as well as the other extreme of only m = 0. A concise review of the results of the general theory of directional correlation of gamma rays from oriented initial states is given.     

Simple formation method of vanadium oxide films with gap states for application in organic optoelectronics

The simple and cost-effective method to form vanadium oxides (VO_x) with high density of gap-states and role of gap-states for organic electronics were investigated. The percentage of V₂O₅ decreased from 82.7% to 29.3% as the deposition rate increased from 0.1 to 1.0 Å/s in thermal evaporation. Synchrotron radiation photo emission spectroscopy revealed that a number of gap states relating to oxygen vacancies was induced near the Fermi level, transporting charges and lowering the hole injection barrier from 0.92 to 0.67 eV. As a result, the operation voltage at 1 mA/cm² was reduced from 8.3 to 5.2 V     

一种高效的准二维管道瞬变流计算方法

为了提高准二维管道瞬变流模型的计算效率,对现有的基于特征线法的准二维模型的算法进行了改进,提出了直接利用一维显式方程计算管道的流量和压力,取代了原算法中需通过数值积分求解平均速度再进一步计算节点压力的方法。该文提出的一维显式方程采用FVS （Flux Vector Splitting）方法,并在水库-管道-阀门系统中,将该方法与两个现有的准二维模型的算法在准确性和计算效率方面进行了比较。结果表明：该文所提出的方法与另外两个算法得到的计算结果基本相同,但是所花费的计算时间更少。因此,该文所提出的方法是一种计算准确并且高效的准二维瞬变流计算方法,适用于管道系统瞬变流的数值模拟分析。     

Daylight photocatalysis performance of biomorphic CeO2 hollow fibers prepared with lens cleaning paper as biotemplate

Hierarchical, biomorphic CeO₂ hollow fibers with mesoporous tube walls have been fabricated using lens cleaning paper as biotemplates. After sintered at 550 °C in air, the cellulosic fibers of paper were converted into micro-tubes composing of CeO₂ crystallites with grain size about 8 nm. The photocatalytic activity of the CeO₂ fibers was evaluated by photodegradation efficiency of methylene blue in aqueous solution under daylight irradiation. The characterized results show that the CeO₂ fibers faithfully replicated micro-fibrous structure derived from original template and possessed dramatic enhanced photocatalytic activity compared with bulk CeO₂. This simple biotemplate method provides a cost-effective and eco-friendly route to obtain high performance photocatalysts.     

磁控溅射法制备WO3薄膜及其氢敏特性研究

采用直流反应磁控溅射法，在未抛光的Al2O3基片上制备WO3薄膜，在干燥空气中经过热处理；利用SEM观察薄膜表面形貌；通过XRD测量，对薄膜的晶体结构进行分析；薄膜氢敏特性测试采用静态配气法。经过400℃热处理，当工作温度在270℃时，对体积分数为3×10^-4%H2的灵敏度达到了77，稳定性较高、选择性好、响应时间在15s以内。WO3薄膜是一种较理想的氢敏材料，在氢敏传感器的设计中必定会得到足够的重视和广泛应用。     

Research on the Drawing-up of the Pole Figure for Orientation Analysis of Directional Si Steel Sheet

1. IntroductionIn general, the magnetic property of polycrystal magnetic materials depends strongly on crystallographic orientation. In particular, necessary crystallographic orientation should be sufficielltly formedin order to increase the magnetic property and decrease loss of St steel sheet used widely as an ironcore material of electric machine products.The crystallographic orientation is analysed bypole figures. Recently in some coulltries, researching process of crystallogrophic orient…