Mold deformation in soft UV-nanoimprint lithography

UV-nanoimprint lithography (UV-NIL) using a soft mold is a promising technique with low cost and high throughput for producing the submicron scale large-area patterns. However, the deformations of the soft mold during imprinting process which can cause serious consequences have to be understood for the practical application of the process. This paper investigated the deformation of the soft mold by theoretical analyses, numerical simulations, and experimental studies. We simulated the mold deformation using a simplified model and finite element method. The simulation and the related experimental results agree well with each other. Through the investigation, the mechanism and affected factors of the mold deformation are revealed, and some useful conclusions have been achieved. These results will be valuable in optimizing the imprinting process conditions and mold design for improving the quality of transferred patterns.     

Multi-channel micro neural probe fabricated with SOI

Silicon-on-insulator(SOI) substrate is widely used in micro-electro-mechanical systems(MEMS).With the buried oxide layer of SOI acting as an etching stop,silicon based micro neural probe can be fabri-cated with improved uniformity and manufacturability.A seven-record-site neural probe was formed by inductive-coupled plasma(ICP) dry etching of an SOI substrate.The thickness of the probe is 15 μm.The shaft of the probe has dimensions of 3 mm×100 μm×15 μm with typical area of the record site of 78.5 μm2.The im...     

基于VAR模型的人力资本与出口贸易增长的关系分析

运用协整和VAR模型从人力资本角度分析其对我国出口贸易额的动态影响,结果表明:人力资本是出口贸易增长的Granger原因,他们之间存在长期的动态稳定关系。脉冲响应分析揭示人力资本对出口额有稳定持续的正的产出弹性,方差分解显示人力资本对出口的贡献占60%多。因此国家必须加大人力资本投资,增加人力资本存量,发挥其内部和外部效应,起到促进出口健康、持续增长的作用。     

动态网络中的高效多故障诊断技术

针对已有算法复杂度较高,不适用于规模较大网络的问题,将被管系统建立成动态贝叶斯模型,并提出一种能处理多故障的近似推理算法. 通过复杂度分析,证明该近似算法时间复杂度为多项式级,远远低于精确算法的时间复杂度下限,可以用于解决大规模动态网络的故障诊断问题. 实验结果证明,新算法在准确度方面虽然略低于精确算法,但执行效率上远远高于精确算法.     

微波辐射磷钼酸铈盐催化柴油氧化脱硫研究

研究微波辐射下磷钼酸铈盐催化模型油和直馏柴油的氧化脱硫反应,考察不同萃取条件对柴油的脱硫率和收率的影响。结果表明,相同反应条件下,相对于普通加热,微波辐射加热时二苯并噻吩（DBT）、苯并噻吩（BT）的脱除率分别提高了4.2倍和3.8倍;在70℃和400 W微波功率下加热2 h,DBT、BT的脱除率分别为95.6%和74.8%;对m（催化剂）/m（柴油）为7.1 mg/g、H2O2初始浓度为0.44 mol/L的柴油,经70℃和4 0 0 W微波功率加热2 h,再在V（萃取剂）/V（柴油）为1/4的条件下用DMF萃取1次,柴油脱硫率为69.6%,收率为97.5%;萃取次数增加,柴油脱硫率提高,但收率明显下降。     

干燥机的最新发展(二)

本文论述了以过热水蒸汽作为干燥介质代替热风的干燥新技术的原理、优越性、存在的问题以及发展前景，并对微波对流干燥器的原理、特点等作了描述。     

图像压缩编码在陶瓷中的应用

随着多媒体和网络技术的发展,图像压缩编码技术显得越来越重要。本文着重介绍了哈夫曼编码、预测编码、小波分析、分形压缩四种图像压缩编码在陶瓷中的应用。     

SARS灭活疫苗的研制及其质量控制

目的研究适合SARS病毒灭活疫苗的生产工艺及其质量控制。方法连续制备3批疫苗,按拟定规程进行疫苗原液和疫苗各项指标检测。结果各项检测指标均符合拟定规程规定。结论我所生产的SARS灭活疫苗工艺稳定,质量可控。     

The existence of a soluble plasmalogenase in guinea pig tissues

The distribution of plasmalogenase for the hydrolysis of 1-alkenyl-2-acyl-sn-glycero-3-phosphoethanolamine (plasmenylethanolamine) in the subcellular fractions of guinea pig tissues was examined. Plasmalogenase activity was found in high abundance in the cytosolic fractions of the brain and the heart. Assessment of microsomal marker enzyme activities in the cytosolic fraction revealed that plasmalogenase activity in the cytosol was not due to microsomal contaminations. The characteristics of the cytosolic plasmalogenase were very similar to the microsomal enzyme with respect to the pH profile of the reaction, the presence of divalent cations and K_m values for plasmenylethanolamine. However, the cytosolic enzyme was slightly less stable at 55°C than the microsomal enzyme. Cytosolic enzyme activity was eluted as a broad peak in Sepharose 6B chromatography with an average molecular weight of 250,000. Our results demonstrate that most of brain plasmalogenase activity is soluble which makes the brain cytosol an excellent source to initiate the purification of this enzyme.     

Effects of NCO/OH molar ratio on miscibility and properties of semiinterpenetrating polymer networks from polyurethane and benzyl konjac glucomannan

Semi‐interpenetrating polymer network (semi‐IPN) films with different NCO/OH molar ratios of the urethane prepolymer, coded as UB, were prepared from polyurethane (PU) and benzyl konjac glucomannan (B‐KGM) by a casting method. The effect of the NCO/OH molar ratio of the urethane prepolymer on the miscibility and properties of the UB films was investigated using Fourier transform infrared spectroscopy, differential scanning calorimetry, dynamic mechanical thermal analysis, thermogravimetric analysis, and swelling and tensile tests. The results indicated that, with an increase of the NCO/OH ratio, the crosslink density of the UB films increased, resulting in improved miscibility between PU and B‐KGM and a relatively high light transmittance of the UB films. However, the thermal stability of the UB films decreased with increase of the NCO/OH ratio of the urethane prepolymer, due to the depolymerization of the urethane bonds of the PU networks. When the NCO/OH ratio increased from 2 to 4, the tensile strength of the UB films increased from 15 to 27 MPa, while the breaking elongation decreased from 72 to 16%, resulting from the chemical and physical crosslinks, namely, the enhancement of the covalent bonds and hydrogen‐bonding networks. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1304–1310, 2003