γ-FeOOH相变和微结构的研究

利用热重分析、差热分析、X 射线衍射、BET 比表面积测定、透射电子显微镜和磁性分析研究了γ—FeOOH 的相变过程和微结构。     

Influence of low energy ballistic electron on the transmittance properties of Au/Si interface studied by ballistic-electron-emission microscope

Conclusions The electronic properties of Au/Si interface are investigated with a homemade ballistic-electron-emission microscope. The spatial distribution of Schottky barrier height is detected. Irreversible changes of ballistic transmittance of local interface with typical size of a few hundred of angstroms in diameter are observed by raising the tip voltage temporarily. Ballistic-electron-emission spectroscopy indicates that the electron transmission probabilities are reduced significantly inside the modified region, which is attributed to the Au-Si intermixing and other chemical reactions occurring at the interfacial layer stimulated by the injected energetic hot electrons.     

Tax Evasion: Models with Self-Audit

Different from traditional tax audit, supervision with self-audit is a combination of audit by the taxpayer himself and audit by the tax authority. This paper mainly studies a taxpayer＇s optimal policy of tax evasion under supervision with self-audit and its related properties, in order to deduce some effective suggestions and theoretical bases to restrain tax evasion. Assuming that only a certain proportion of evaded tax can be discovered when the audit is executed, the authors first formulate a static model with self-audit. This model is divided into two stages. At the first stage, taxpayers declare their taxes, then the tax authority chooses audit objects, based on a known probability, and announces the result; if the taxpayer is chosen, he will enter the second stage, during which he has a chance to pay the evaded tax and the corresponding late fees and then is audited by the tax authority. The authors show the existence and uniqueness of the optimal amount of tax evasion at the first stage and the optimal proportion to self-expose at the second stage. The authors also discuss the related properties of the interior solution, and do elasticity analyses on some parameters. Besides, the authors extend the static model into the corresponding two-period model, and study the existence and uniqueness of the solution of the extended model. Finally, under the assumption that tax evasion can only be discovered with a certain probability when the audit is executed, the authors formulate another static model with self-audit and investigate its properties.     

膜片弹簧最大应力的实验研究

用光弹性贴片法得到膜片弹簧在小端加载时上表面全场应力的分布,再用电测法精确测定可能为最大应力的各点应力,从而得到膜片弹簧在危险工况下最大应力是处于凹槽边缘中点,而不是在分离指根部中点的结论。并指出目前通用的膜片弹簧强度计算方法所确定的危险点位置及最大应力数值都与实际情况有较大的出入,有必要进行修改。     

Vanadyl ions binding to GroEL （HSP60） and inducing its depolymerization

Several vanadium compounds have been known for the hypoglycemic and anticancer effects. However, the mechanisms of the pharmacological and toxicological effects were not clear. In this work, we in- vestigated the potential targets of vanadium in mitochondria. Vanadyl ions were found to bind to mi- tochondria from rat liver with a stoichiometry of 244±58 nmol/mg protein and an apparent dissocia- tion constant (Kd) of (2.0±0.8)×10·16 mol/L. Using size exclusion chromatography, a vanadium-binding protein was isolated and identified to be the 60-kDa heat shock protein (HSP60) by mass spectrometry analysis and immunoassays. Additionally, binding of vanadyl ions was found to result in depolymeri- zation of homo-oligomeric HSP60 (GroEL). HSP60 is an indispensable molecular chaperone and in- volved in many kinds of pathogenesis of inflammatory and autoimmune diseases, e.g. type 1 diabetes. Our results suggested that HSP60 could be a novel important target involved in the biological and/or toxicological effects of vanadium compounds.     

传递函数拟合算法及其在变压器绕组变形诊断中的应用

提出了利用网络的实测数据拟合其传递函数的实用算法。本算法是基于当某极点的实部较小时，该极点对网络传递函数的作用区域集中于其虚部附近，所以利用其虚部近的测量数据可以较准确的拟合同该极点。对拟合结果使用高斯－赛德尔型迭代法进行修正可以进一步改善所得结果。对几组变压器的实测数据所做的计算证实了所提出的算法，此外对传递函数的拟合在变压器绕组变形中的可能应用进行了探讨。     

Quantitative Estimates of Outcrossing Rates in a Natural Population of Caldesia grandis （Alismataceae）

Outcrossing rate in a natural population of Caldesia grandis was estimated by the dominant random amplified polymorphism DNA (RAPD) marker using 10 open-pollinated progeny arrays of 24 individuals. The multilocus outcrossing rate estimated based on all 25 RAPD loci was 0.872 ±0.033 and the single-locus outcrossing rate was 0.795 ±0.032. Multilocus estimates did not differ significantly from the single-locus estimates. The fixation index, F, in the progeny estimated from RAPD data was -0.142 ±0.000. The estimates of multilocus outcrossing rates (t_m) and single-locus outcrossing rates (t_s) obtained from MLDT clearly indicate that outcrossing is predominant in the open-pollinated C. grandis population. An empirical analysis suggests that 15 should be the minimum number of dominant marker loci necessary to achieve robust estimates of t_m.     

A PLL Clock Frequency Multiplier Using Dynamic Current Matching Adaptive Charge-Pump and VCO Frequency Reuse

A 3.5 times PLL clock frequency multiplier for low voltage different signal （LVDS） driver is presented. A novel adaptive charge pump can automatically switch the loop bandwidth and a voltage-controlled oscillator （VCO） is designed with the aid of frequency ranges reuse technology. The circuit is implemented using 1st Silicon 0.25 μm mixed-signal complementary metal-oxide-semiconductor （CMOS） process. Simulation results show that the PLL clock frequency multiplier has very low phase noise and very short capture time .     

A FRAMEWORK FOR REAL-VALUED CIPHER SYSTEMS

Most cipher systems designed thus far are binary-valued or integer-valued cipher systems. Their security relies on the assumption that one-way functions exist. Though the existence of one-way functions has not been proved yet, most cryptographic researchers believe that one-way functions exist. In addition, many candidates for one-way functions have been proposed. Therefore, the key step for developing real-valued cipher systems is to define real one-way functions and to propose candidates for them. In this paper, based on computational complexity theory over the real field, we give two definitions of real one-way functions; one is for digital one-way functions and the other is for general one-way functions. Candidates for these two classes of one-way functions are also proposed. Moreover, we present two examples to demonstrate that the candidates for both digital one-way functions and general one-way functions can be applied to construct secure real-valued cipher systems.