脉冲爆震发动机试验模型测控系统设计与实现

针对新型推进系统脉冲爆震发动机试验模型的多通道高速采集和实时控制的要求,设计并实现了发动机的实时测控系统．并重点介绍了系统的软硬件体系结构以及抗干扰、网络通讯及数据库存储等关键技术;经实际应用表明。系统实时性强,可靠性高,满足试验模型对高速采集和控制时间的要求。     

极谱吸附波测定金属锌中微量镉

在pH5.5的HAc -NaAc -抗坏血酸 -KI溶液中 ,用单扫描示波极谱法获得镉与KI络合物极谱吸附波 ,其峰电位在 -0.73V( vs SCE) ,镉在 0 .4～ 80 μg/5 0mL范围 ,峰电流与镉的浓度呈良好的线性关系 ,方法用于金属锌中镉的测定 ,获得令人满意的结果     

Application of new double side approach method to the solution of super-elliptical plate problems

The new double side approach method combining the mathematical programming and the subdomain method in the method of weighted residual is presented in this article. Under the validation of maximum principle, and up on the subdomain method, the differential equation can be transferred into a bilateral inequality problem. Applying the genetic algorithms helps to find optimal solutions of upper and lower bounds which satisfy the inequalities. Here, the method is first verified by analyzing the deflection of elliptical clamped plate problem under various aspect ratios and further apply it to analyze the clamped super-elliptical plates problem. By using this method, the good approximate solution can be obtained accurately.     

Analysis and application of nonleaky uniplanar structures with conductor backing

Novel conductor-backed uniplanar structures, including the nonleaky CPW and slotline, are analyzed and applied to the active antenna design. Both the spectral domain analysis and finite-difference time-domain techniques are used to simulate these circuits and to justify the numerical results. The measured gain of the novel active antenna is 1.7 dB higher than the conventional CPW antenna due to the unidirectional radiation of conductor-backed circuits. © 1996 John Wiley & Sons, Inc.     

Effect of substrate on the phase transformation of TiO2 in pearlescent pigment

The TiO₂/substrate pearlescent pigments were prepared by the hydrolysis of TiOCl₂ on the substrate followed by a calcinations process. The natural mica (muscovite), synthetic mica (fluorophlogopite) and -alumina flake were selected as the substrates for pearlescent pigments. The effect of substrate on the anatase to rutile (A–R) phase transformation of TiO₂ was studied. The A–R phase transformation of TiO₂ during the preparation of pearlescent pigments and their proportion in the TiO₂ layer have been analyzed by XRD measurements. The phase compositions of TiO₂ layer in each pearlescent pigment are quite different depending on the substrates. The TiO₂ layer deposited on -alumina has higher rutile fraction than those on the natural and synthetic mica. The XPS analysis showed that the cations originally present in the substrates diffused into the TiO₂ layer. The TiO₂ layer deposited on -alumina contains Al, while those on the natural and synthetic mica substrates contain Si and K in addition to Al. The metal cations diffusing from the substrate into TiO₂ layer might retard the A–R phase transformation of TiO₂. The suppressing effect on the A–R transformation of TiO₂ by mixed cations seems to be much stronger than that of single cation, resulting in relatively higher rutile fraction in the case of TiO₂ layer deposited on -alumina.     

Physical properties of ethylene vinyl acetate copolymer (EVA)/natural rubber (NR) blend based foam

In this study an attempt was made to improve the rebound resilience and to decrease the density of ethylene‐vinyl acetate copolymer (EVA) foam. For this purpose, EVA was blended with natural rubber (NR), and EVA/NR blends were foamed at 155°C, 160°C, and 165°C. To investigate the correlation between crosslinking behavior and physical properties of foams, crosslinking behavior of EVA/NR blends was monitored. The physical properties of the foams were then measured as a function of foaming temperatures and blend compositions: 165°C was found to be the optimal temperature for a crosslinking of EVA/NR foam. As a result, the density of EVA/NR blend foamed at 165°C was found to be the lowest. EVA/NR (90/10) blend, foamed at 165°C, showed lower density, better rebound resilience, and greater tear strength than EVA foam. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2212–2216, 2004     

高通量工程试验堆栅元型随堆辐照装置的研制、试验与应用

高通量工程试验堆(HFETR)内的栅元型辐照装置具有较大的灵活性和适用性。几年来,我们使用这类装置开展了一系列材料考验及同位素生产工作。本文介绍了这类装置的设计思想、应用范围、结构特点和试验结果。可供进一步开展栅元型装置研制工作参考。     

A Highly Reliable Molybdenum Disulfide-Based Synaptic Memristor Using a Copper Migration-Controlled Structure

Memristors are drawing attention as neuromorphic hardware components because of their non-volatility and analog programmability. In particular, electrochemical metallization (ECM) memristors are extensively researched because of their linear conductance controllability. Two-dimensional materials as switching medium of ECM memristors give advantages of fast speed, low power consumption, and high switching uniformity. However, the multistate retention in the switching conductance range for the long-term reliable neuromorphic system has not been achieved using two-dimensional materials-based ECM memristors. In this study, the copper migration-controlled ECM memristor showing excellent multistate retention characteristics in the switching conductance range using molybdenum disulfide (MoS₂) and aluminum oxide (Al₂O₃) is proposed. The fabricated device exhibits gradual resistive switching with low switching voltage (<0.5 V), uniform switching (σ/µ ∼ 0.07), and a wide switching range (>12). Importantly, excellent reliabilities with robustness to cycling stress and retention over 10⁴ s for more than 5-bit states in the switching conductance range are achieved. Moreover, the contribution of the Al₂O₃ layer to the retention characteristic is investigated through filament morphology observation using transmission electron microscopy (TEM) and copper migration component analysis. This study provides a practical approach to developing highly reliable memristors with exceptional switching performance.