径向磁悬浮轴承结构特性研究及其模型的建立

本文分析研究了径向可控磁悬浮轴承的多磁极结构对系统模型的影响，推导并建立了一种新的考虑耦合作用的数学模型。     

CuO/ZnO甲醇合成催化剂的正电子湮没谱学研究

发展了用正电子湮没寿命参数测定用共沉淀方法制备的金属氧化物系固溶度的新方法。测量了一系列用共沉淀方法制备的不同CuO at％含量的CuO/ZnO甲醇合成催化剂粉末(压制成片)还原前后的正电子寿命谱。分析该种催化剂的固溶特性及其与正电子寿命参数的关系,得出还原后样品的固溶度为12CuOat％.支持了CuO/ZnO甲醇合成催化剂以Cu~+离子为活性中心的观点。     

自动线性跟踪Butterworth有源滤波器研究

滤波是通信、测试、数据采集和实时控制等领域至关重要的环节。通常的模拟滤波器，由于截止频率固定，在某些宽频率动态范围且有实时性要求的应用场合，往往达不到预期的滤波效果，有时甚至影响整个系统的正常运行。本文从有源滤波器的机理分析入手，提出了一种由单片机参与的滤波系统，它能自动跟踪输入信号频率，线性地选择合适的滤波器截止频率，弥补了原有滤波器的不足。     

半导体激光器列阵有源区电场随电流变化的定点测量

采用连续波电光检测法，对ＧａＡｓ／ＧａＡｌＡｓ双异质结激光器列阵有源区进行定点测量，实验结果反映了发光区内及发光区外电场随电流变化的不同规律。文中对实验结果给出了合理解释。     

Observer-based wheelbase preview control of active vehicle suspensions

Optimal observer-based wheelbase preview regulator problem is investigated for active vehicle suspension systems. It is shown that the problem reduces to the classical linear quadratic Gaussian problem, whose solution is well defined, by augmenting dynamics of system and road inputs. The resulting optimal controller is in the form of augmented state feedback controller and this augmented state is estimated by Kalman-Bucy filter using dynamics of the augmented system. Numerical examples of a half car model are given to verify the performance improvement achievable with the proposed controller.     

自适应有源噪声控制的滤波-LMAD算法

本文研究了稳定非高斯环境下的自适应有源噪声控制问题，提出了滤波－ＬＭＡＤ（ｌｅａｓｔｍｅａｎａｂｓｏｌｕｔｅｄｅｖｉａｔｉｏｎ）算法及归一化滤波－ＬＭＡＤ算法，仿真结果表明，与常用的滤波－ＬＭＳ算法和归－化滤波－ＬＭＳ算法相比，本文提出了算法收敛速度更快。     

镧系钙钛矿型氧化物（LaBO3）的催化氧化性能及其净化效果的研究

本文在气相色谱仪联用微反应器装置上,研究了LaBO_3型催化剂中的B位元素对催化氧化活性的影响规律,并进行了程序升温脱附实验。另外,还对LaBO_3型载体催化剂进行了活性筛选,并在柴油机台架上与贵金属Pt/Al_2O_3进行了有害气体净化效果的对比实验。实验结果表明,LaBO_3氧化物中LaMnO_3对CO、CH_4的催化氧化活性最高,且CO、CH_4活性中心并不一致。LaMnO_3/γ-Al_2O_3浸渍微量助化剂后,能使CO在130℃完全氧化,CH_4的氧化温度在300～500℃范围内,LaMnO_3载体催化剂对柴油机有害排放物的净化率很低,浸渍微量助化剂后,净化率提高一倍以上,特别是LaMnO_3/堇青石蜂窝陶瓷,浸渍后的净化效果同贵金属Pt/Al_2O_3接近。     

The use of natural essential oils as antimicrobial solutions in paper packaging. Part II

We have assessed the antimicrobial, vapor-phase activity of the following natural essential oils (EOs) when used in paraffin-based “active coatings” for paper packaging materials intended to come into contact with foods: clove (Sygzium aromaticum), cinnamon (Cinnamomum zeylanicum), and oregano (Origanum vulgare) EOs, and cinnamaldehyde-enriched cinnamon EO. To our knowledge, this is the first time that such an approach has been presented for consideration by the scientific community.     

Surface movements in Bologna (Po Plain — Italy) detected by multitemporal DInSAR

We studied the surface deformations affecting the southeastern sector of the Po Plain sedimentary basin, in particular the area of Bologna. To this aim an advanced DInSAR technique, referred to as DInSAR-SBAS (Small BAseline Subset), has been applied. This technique allows monitoring the temporal evolution of a deformation phenomenon, via the generation of mean deformation velocity maps and displacement time series from a data set of acquired SAR images. In particular, we have processed a set of SAR data acquired by the European Remote Sensing Satellite (ERS) sensors and compared the achieved results with optical levelling measurements, assumed as reference. The surface displacements detected by DInSAR SBAS from 1992 to 2000 are between 10 mm/year in the historical part of Bologna town, and up to 59 mm/year in the NE industrial and agricultural areas. Former measurements from optical levelling referred to 1897 show 2-3 mm/year vertical movements. This trend of displacement increased in the second half of the 20th century and the subsidence rate reached 60 mm/year. We compared the more recent levelling campaigns (in 1992 and late 1999) and DInSAR results from 1992 to 1999. The standard deviation of the difference between levelling data, projected onto the satellite Line Of Sight, and DInSAR results is 2 mm/year. This highlights a good agreement between the measurements provided by two different techniques. The explanation of soil movements based on interferometric results, ground data and geological observations, allowed confirming the anthropogenic cause (surface effect due to the overexploitation of the aquifers) and highlights a natural, tectonic, subsidence.     

Method of Reducing Error in Calculations of Active Power from Signal Samples

The paper presents the results of investigations into several methods of calculating the active power value from current and voltage signal samples. The accuracy attainable for nonsinusoidal signals whose frequency differs from the nominal one was determined. A new active power calculation method ensuring accurate results for sampling over two signal periods is proposed. The method uses a very simple computing algorithm.