露天矿山裂隙岩体爆破孔距变化的研究

文中指出裂隙岩体大孔距爆破在一点条件下与结构面的特性变化关系密切，并按两组三结构面建立了孔距计算公式。     

PZT铁电薄膜的制备及电学性能研究

使用硝酸锆作锆源的溶胶－凝胶方法制备ＰＺＴ铁电薄膜。他们的电学性能被测试包括电滞回线，电流Ｉ（ｔ）特性，漏电流，矫顽场疲劳和老化。测到的ＰＺＴ薄膜剩余极化８．２μＣ／ｃｍ~２，矫顽场６８ｋＶ／ｃｍ．簿膜的寿命可超过１０~（１１）周期。     

Dynamic oxide voltage relaxation spectroscopy

A new method for trap characterization of oxidized silicon is described. The Dynamic Oxide Voltage Relaxation Spectroscopy (DOVRS) is an improved version of the formerly proposed Oxide Voltage Relaxation Spectroscopy (OVRS) technique which applies a periodic long duration constant current for tunneling injection. It has been demonstrated that the new technique can be used not only to separate and identify the oxide trap from interface trap, but also to separate and determine the centroid from the oxide trap density generated in the MOS system by the tunneling current stress. In the pulse constant current mode, the OVRS measurement can be completed instead of using the double current-voltage technique. Thus the new method results in more accurate and quicker measurements of the oxide trap centroid. Analytical expressions for computing the paramaters of the interface and oxide traps are derived. The effect of the channel carrier mobility on the spectroscopy is also considered. Two types of oxide and two types of interface traps were observed at a pulse constant Fowler-Nordheim current stress by the new method of DOVRS     

The preparation and magnetic properties of Fe-Ag granular solid using a sol-gel method

The Fe-Ag granular metal solid samples with 10% and 30% weight iron have been successfully fabricated using a sol-gel method, which are characterized by X-ray diffraction and transmission electron micrography. The average diameters of iron particles are from about a few nanometres to a few tens of nanometres controlled by the reducing temperature. The evolution of magnetic properties and microstructure during heat treating are described in detail and explained by using the superparamagnetism, single domain and multi domain theories. The magnetic anisotropy of the Fe-Ag granular solid is studied by using the law of approach to saturation. It is found that the magnetic anisotropy constant is in the order of 10⁵ J m^–3 which is higher than the value of the bulk iron and increases with the increase of reducing temperature.     

Time-varying adaptive filters for evoked potential estimation

Adaptive implementation of an optimal time-varying filter (TVF) for evoked potential (EP) estimation is addressed here. A data-adaptive scheme is used, which converges asymptotically to the optimal TVF solution. Two basic adaptive TVF's (ATVF's) are first introduced, namely least mean square (LMS) ATVF and recursive least-squares (RLS) ATVF. The latter converges much faster than the former. Since the basic ATVF's usually require a relatively large set of response trials to get a meaningful solution, a reduced-order ATVF is further presented and the corresponding LMS and RLS (including a fast RLS) adaptive algorithms are developed. To save memory, a truncated Fourier expansion is suggested to express approximately the time-sequenced weight-vectors of the ATVF's, resulting in a simplified reduced-order ATVF. Finally, extensive simulations are provided to confirm the superior performance of the ATVF's. The present ATVF's can be used as prefilters for latency-corrected average (LCA) processing to obtain more informative estimates of EP signals     

用于生产甲基丙烯酸的杂多酸催化剂的研究

以异丁烯为原料的两段直接氧化生产甲基丙烯酸最新工艺有许多优点。其技术关键在于研制出高效的甲基丙烯醛选择性氧化催化剂。本文报道P-Mo-As-Cu杂多化合物催化剂的组成、制备条件对催化剂活性的影响。经优化后获得高选择性、高活性的二段氧化催化剂，其甲基丙烯酸收率达60％以上。     

用于实时测量负重轮轮胎温度场的红外遥测系统

为研究坦克装甲车辆行使过程中负重轮轮胎内部的温度分布，研制了一种用于实时测量轮胎内部温度的多路遥测装置。该装置温度信号的传输采用了红外线无线光通信技术，免去了连线，可广泛应用于旋转件中及其它不便连线场合测量信号的传输。该文详细介绍了这一装置的工作原理及各部分的关键技术。     

The geometry effects for stress intensity factor of sandwich specimen for measuring interfacial fracture toughness

The interfacial stress intensity factors for three types of sandwich specimens: the single edge crack tensile specimen, the three point bend specimen and the four point shear specimen were obtained by the finite element analysis and compared with the asymptotic solutions. The results show that the geometric effect for mode II specimen is larger than mode I specimen. The limit curves for geometry factor equal to 1.05 were obtained to indicate the usable range of validity of the asymptotic solution.     

An experimental study of pathomorphology in the iris and ciliary body after intraocular lens implantation]

Recent studies have suggested that cytokines play a critical role in the pathophysiology of alopecia areata; however, no information is available regarding the difference in cytokine profiles in these patients. Serum levels of cytokines, including interferon gamma (IFN-gamma), tumor necrosis factor alpha, interleukin 1 alpha (IL-1 alpha), IL-2, IL-4, and IL-6, were measured using radioimmunoassay or enzyme-linked immunosorbent assay techniques in patients with the localized form and the extensive form (alopecia universalis). The serum levels of IL-1 alpha and IL-4 were significantly elevated in patients with the localized form. In contrast, the serum levels of IFN-gamma and IL-2 were significantly elevated in patients with the extensive form. These results indicate that immune responses in the localized form and the extensive form of alopecia areata are regulated by Th2 cytokines and Th1 cytokines, respectively.