A NOTE ON FULLER'S THEOREM

In 1972, Fuller proved that a complete additive subeategory _RC of R-Mod isequivalent to amodule category ⊿-Mod if and only if _RC=Gen(_RU)for some quasiprogenerator _RU and ⊿≌End _RU canonically. In this note the author gives a characterization of _RC which makes _RU a projective R-module in the case when R is a right perfect ring with identity, and shows that R-Mod is the unique complete additive subcategory of R-Mod which is equivalent to R-Mod for a left Artinian ring R.     

在对称群Sm中解循环方程组

本文研究了在对称群S_m中解循环方程组:x_mX_(m+1)…x_(ω+k-1)σ_m,其中σ_m∈S_m,ω=1,2,…,s,确定了这个循环方程组有解的充分必要条件和解的个数,而且给出了求解过程。     

利用KTP晶体实现1.08μmNd：YAP激光器锁模

本文描述了利用ＫＴＰ晶体和腔的基波输出镜构成非线性镜实现１．０８μｍＮｄ：ＹＡＰ激光器的被动锁模。实验表明，这种新的锁模技术比用染料作可饱和吸收体的被动锁模技术有很多突出的优点，具有很大的发展潜力。实验测得锁模时基波１．０８μｍ输出２．４ｍＪ，二次谐波０．５４μｍ输出０．５ｍＪ（同样条件下的静态输出为２．５ｍＪ），基波脉冲的平均脉宽为４０ｐｓ。     

关系模式关键字的一个求解算法

本文给出了关系数据库模式中求解关键字的一个算法。算法很简洁并且对于[1]定义的一大类问题,执行时间是多项式级的。     

Erratum: Preparation of size‐controlled In2O3 nanoparticles

The article referenced above was first published online on 7 August 2007 with incorrect pagination; the pagination has now been corrected online and in print. Copyright © 2007 John Wiley & Sons, Ltd.     

Frame Wavelets with Compact Supports for L^2（R^n）

The construction of frame wavelets with compact supports is a meaningful problem in wavelet analysis. In particular, it is a hard work to construct the frame wavelets with explicit analytic forms. For a given n × n real expansive matrix A, the frame-sets with respect to A are a family of sets in R^n. Based on the frame-sets, a class of high-dimensional frame wavelets with analytic forms are constructed, which can be non-bandlimited, or even compactly supported. As an application, the construction is illustrated by several examples, in which some new frame wavelets with compact supports are constructed. Moreover, since the main result of this paper is about general dilation matrices, in the examples we present a family of frame wavelets associated with some non-integer dilation matrices that is meaningful in computational geometry.     

Hydroxyapatite coating on porous silicon substrate obtained by precipitation process

Hydroxyapatite Ca₁₀(PO₄)₆(OH)₂ (HAP) is known as a bioactive and biocompatible material, HAP coatings were used to improve the biocompatible of substrate by many researcher, In this work, HAP thin films on porous silicon (PS) substrates have been prepared by aqueous precipitation method with rapid thermal annealing (RTA) processes. The HAP films had been prepared under the annealing temperature ranging from 300 to 1000 °C. By the measurement of X-ray diffraction (XRD), it was found that for the crystallinity optimization, the heat-treatment at 850–950 °C for 1 h would be favorable. Atomic force microscopy (AFM) and scanning electron microscope (SEM) measurements reveal a dense and smooth surface of the HAP film, and tightly adherence of the coating on porous silicon substrate after sintered. Thus, by this method, porous silicon could be increased its bioactivity and so that could be used in the biomedical area.     

MEASUREMENTS OF Fe AND Cu K-Shell IONIZATION CROSS SECTIONS BY SLOW ELECTRON IMPACT

ＭＥＡＳＵＲＥＭＥＮＴＳＯＦＦｅＡＮＤＣｕＫ－ＳｈｅｌＩＯＮＩＺＡＴＩＯＮＣＲＯＳＳＳＥＣＴＩＯＮＳＢＹＳＬＯＷＥＬＥＣＴＲＯＮＩＭＰＡＣＴＬｉＴａｉｈｕａＡｎＺｈｕＬｕｏＺｈｅｎｇｍｉｎｇＣｅｎｔｅｒｆｏｒＲａｄｉａｔｉｏｎＰｈｙｓｉｃｓ，Ｉｎｓ...     

Measurement of small-signal and large-signal responses of packaged laser modules at high temperature

In this paper, the pulsed injection method is extended to measure the chip temperature of various packaged laser modules, such as the DFB laser modules, the FP laser modules, and the EML laser modules. An optimal injection condition is obtained by investigating the dependence of the lasing wavelength on the width and period of the injection pulse in a relatively wide temperature range. The small-signal frequency responses and large-signal performances of packaged laser modules at different chip temperature are measured. The adiabatic small-signal modulation characteristics of packaged LD are first extracted. In the large-signal measurement, the effects of chip temperature, bias current and driving signal on the performances of the laser modules are discussed. It has been found that the large-signal performances of the EML modules depend on the different red-shift speeds of the DFB and EAM sections as chip temperature varying, and the optimal characteristics may be achieved at higher temperature.