Effects of Ar and O2 additives on photopatternable sol-gel etching in an SF6-based plasma for planar lightwave circuit fabrication

We present a novel study of the interaction of SF₆-based plasmas with sol-gel materials in a parallel plate reactive ion etching (RIE) system. The purpose of these experiments was to obtain quantitative measures and optimisation of the RIE parameters, which can be used in the microfabrication of planar lightwave circuit (PLC) devices. The sulfur hexafluoride chemistry is chosen due to its excellent etching properties of SiO₂, which is one of the components of the photopatternable sol-gel materials and is not present in typical photoresist materials. Fast process etching rate and good selectivity is achieved by varying SF₆ flow and power delivered to the electrodes. The study also reveals a marginal influence of oxygen and argon flow on the character of the sol-gel etching. The experimental data obtained can be used as a reference for any sol-gel devices fabricated using widely available RIE reactors.     

LiFePO4: From molten ingot to nanoparticles with high-rate performance in Li-ion batteries

LiFePO₄ (LFP) particles were obtained by grinding ingot synthesized in the molten state. This process, followed by jet milling, and then wet milling, provides a simple way to obtain powders with controlled particle size in the range from macroscopic to 25 nm. However, at this time, we find that these particles tend to agglomerate to form secondary particles of size ∼100 nm. The particles obtained by this process are characterized by X-ray diffraction (XRD). In situ and ex situ scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The effect of milling was also investigated by analysis of physical properties using infrared spectroscopy (FTIR) and magnetic measurements. The electrochemical performance was evaluated in cells containing Li/1 M LiPF₆ in EC:DEC (1:1)/C-LiFePO₄. After carbon coating, the LFP particles which are free of impurities, exhibit high-rate capability. Even with a limited amount of carbon (2 wt.%) appropriate for commercial batteries, the capacity is 157 mAh g⁻¹ at 0.1 C, 120 mAh g⁻¹ at 10 C, without capacity fading after 60 cycles.     

广义密钥探究

本文提出广义密钥的概念,针对量子计算机对现有密码体制安全性的挑战,独辟蹊径地提出一些与计算能力无关的想法如对尽量多的广义密钥保密的概念,多重加密,信息迷惑,回避计算机的高速超运算,软硬件密文。同时提出一些对密码学有意义的发展思路。     

台北凹陷反转构造特征与油气关系浅析

分析解剖了吐哈盆地台北凹陷几个典型的反转构造，结合已知油气田的分布特点，从区域构造演化的角度，探讨了反转构造与油气聚集的关系。认为台北凹陷的反转构造主要发育在侏罗纪，表现为逆断层上盘的中，下侏罗统厚度明显加大，是由早期的同生正断层在晚期在逆断层方式活动形成的断层上盘的正反转构造，其发展演化与区域应力场的演变息息相关。     

La mesure de perfectionnisme: Validation canadienne-fran?aise du Positive and Negative Perfectionism Scale.

The purpose of this study was to verify the validity of a French version of the Positive and Negative Perfectionism Scale developed by L. A. Terry-Short (1995). This instrument measures the type as well as the level of perfectionism in adolescents. The instrument was first administered to 734 7th, 9th, and 11th grade students. Four weeks later, 596 Ss were invited to answer the questionnaire once more. The factorial structure, temporal stability and internal consistency of each subscales of the translated version of the instrument correspond to those of the original version. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

圆度误差评定中删点技术的应用

在最小二乘法的基础上采用中心移动逐步搜索 ,能够不需试探便可确定搜索方向。然后利用最小二乘圆将误差圆分成正域和负域两部分 ,使计算量大大减少。在此基础上再利用删点技术将一些不必要用于计算的点删去 ,进一步减少计算量。这种技术应用于圆度误差最小区域评定中不但能够保证计算的精确度 ,而且达到了检测快速的目的。     

具有速度正反饋的变带宽伺服系统分析及其数字仿真

本文分析了速度正反馈变带宽伺服系统特点,它在精度及快速性方面接近于再生反馈系统,但结构简单、工作可靠、调整维护方便。通过线性仿真,定量分析了系统动态指标,验证了理论设计参数合理性。通过非线性仿真,定量分析了理论分析比较困难的动态响应问题,得到了一些有益的结论。     

从《日本食品中农业化学品残留肯定列表制度》探讨我国输日农产品的应对措施

日本政府将在2006年5月29日起实施《日本食品中农业化学品残留肯定列表制度》。现对该制度的修改动因、修改过程、修改前后内容的变化以及对中国农产品出口的影响作一介绍,并提出了建议和基层相关企业宜采取的应对措施。     

Robust fault detection for switched positive linear systems with time-varying delays

This paper investigates the problem of robust fault detection for a class of switched positive linear systems with time-varying delays. The fault detection filter is used as the residual generator, in which the filter parameters are dependent on the system mode. Attention is focused on designing the positive filter such that, for model uncertainties, unknown inputs and the control inputs, the error between the residual and fault is minimized. The problem of robust fault detection is converted into a positive L₁ filtering problem. Subsequently, by constructing an appropriate multiple co-positive type Lyapunov–Krasovskii functional, as well as using the average dwell time approach, sufficient conditions for the solvability of this problem are established in terms of linear matrix inequalities (LMIs). Two illustrative examples are provided to show the effectiveness and applicability of the proposed results.     

Preparation of BaPbO3 functional ceramics from leaded waste

In this study, Pb was separated and used to prepare BaPbO3 conductive ceramics from leaded waste.The experimental results show that BaPbO3 powder synthesized at 700 °C has particle size of 2–5 lm. The powders were densified by sintering at 1,000 °C for 2 h in the air.Synthesized BaPbO3 ceramics have high Curie temperature and high-temperature positive temperature coefficient（PTC） resistivity characteristics. Electrical resistivity of BaPbO3 compact increases from 5 × 10^-6Ω·m at room temperature to 4 × 10^-4Ω·m at 750 °C. Compared with the one prepared by pure chemical reagents, the BaPbO3 prepared from leaded waste has the similar characteristics of high Curie temperature and PTC resistivity.