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101.
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XU Rong-guo YAO Jian-xi LAI Xiao-yong MAO Dan XING Chao-jian WANG Dan .State Key Laboratory of Multi-phase Complex System 《高等学校化学研究》2009,25(1)
By the UV-curing method, a porous TiO2 film with net-like framework has been prepared. The characte-rization results of the porous TiO2 film by means of SEM, TEM, XRD, and N2 adsorption-desorption analysis show that the net-like framework of the porous TiO2 film is composed of TiO2 nanoparticles, forming three dimensional porous structure. The porous TiO2 film exhibits higher photocatalytic activity for the degradation of methylene blue(MB) dye compared with the conventional dense TiO2 film. 相似文献
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补充养老保险、医疗保险是在基本养老保险、医疗保险基础上,政府以政策指导和政策优惠为导向,用工单位和员工共同出资,以资金积累和运作增值为主要特征,以提高出资单位员工的养老待遇为主要特点的社会保险的重要组成部分。 相似文献
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A digital still camera image processing system on a chip, different from the video camera system, is pre- sented for mobile phone to reduce the power consumption and size. A new color interpolation algorithm is proposed to enhance the image quality. The system can also process fixed patten noise (FPN) reduction, color correction, gamma correction, RGB/YUV space transfer, etc. The chip is controlled by sensor regis- ters by inter-integrated circuit (I2C) interface. The voltage for both the front-end analog and the pad cir- cuits is 2.8 V, and the volatge for the image signal processing is 1.8 V. The chip running under the external 13.5-MHz clock has a video data rate of 30 frames/s and the measured power dissipation is about 75 roW. 相似文献
108.
A method for detecting the target echo in reverberation was proposed based on fractional Fourier transform theory when the transmitted signal is linear frequency modulation signal. The slow time-varying envelope of reverberation is computed to process reverberation to be stationary. The stationary reverberation is cut into blocks using a sliding window. A narrow-band filter is applied in FrFT domain for each block and the signal is recovered through inverse FrFT. Output of the system is the energy of the recovered signal. When the target echo is included in one of the blocks, the reverberation noise is reduced, and the output is the energy of the target echo. All the simulation and lake experiment results show that the detection performance of the present method is better than that of the matched filter. 相似文献
109.
SUN Hui XU Ying-kai XU Guo-zhi 《高等学校化学研究》2010,(4):667-671
<正>The present paper covers the extraction of hemicelluloses from woods,i.e.,Eucalyptus Globulus,white fir and Douglas fir via green liquor pretreatment and alkali post-treatment with sodium hydroxide.The effects of such extraction conditions as extraction time,temperature on the yields of hemicellulose and the degree of deliginification were investigated.Sugar analyses using Dionex indicate that xylose,glucose and mannose are the main sugar types present in the hemicellulose from Eucalyptus.Other sugar components such as arabinose and galactose were also found in Dogulas fir hemicellulose.The highest yield of hemicellulose was 8.4%for Eucalyptus extracted with green liquor at 130℃for 3.5 h.Further sodium hydroxide extraction for 5 h gave a hemicellulose yield of about 20%.The use of green liquor for the extraction of wood hemicellulose is believed to be the first attempt. 相似文献
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高压静电场促进植物生物技术的研究 总被引:2,自引:0,他引:2
高压静电场促进植物生长技术源于自然又高于自然。它包括静电种子处理和静电场生长环境等技术。文章论述了该技术的实施方法,并报道了 取得的初步成果。 相似文献