Synthesis of biodiesel from waste cooking oil using immobilized lipase in fixed bed reactor

Waste cooking oil (WCO) is the residue from the kitchen, restaurants, food factories and even human and animal waste which not only harm people's health but also causes environmental pollution. The production of biodiesel from waste cooking oil to partially substitute petroleum diesel is one of the measures for solving the twin problems of environment pollution and energy shortage. In this project, synthesis of biodiesel was catalyzed by immobilized Candida lipase in a three-step fixed bed reactor. The reaction solution was a mixture of WCO, water, methanol and solvent (hexane). The main product was biodiesel consisted of fatty acid methyl ester (FAME), of which methyl oleate was the main component. Effects of lipase, solvent, water, and temperature and flow of the reaction mixture on the synthesis of biodiesel were analyzed. The results indicate that a 91.08% of FAME can be achieved in the end product under optimal conditions. Most of the chemical and physical characters of the biodiesel were superior to the standards for 0(#)diesel (GB/T 19147) and biodiesel (DIN V51606 and ASTM D-6751).

Design and Operation of A 5.5 MWe Biomass Integrated Gasification Combined Cycle Demonstration Plant

The design and operation of a 5.5 MWe biomass integrated gasification combined cycle (IGCC) demonstration plant, which is located in Xinghua, Jiangsu Province of China, are introduced. It is the largest complete biomass gasification power plant that uses rice husk and other agricultural wastes as fuel in Asia. It mainly consists of a 20 MWt atmospheric circulating fluidized-bed gasifier, a gas-purifying system, 10 sets of 450 kW(e) gas engines, a waste heat boiler, a 1.5 MWe steam turbine, a wastewater treatment system, etc. The demonstration plant has been operating since the end of 2005, and its overall efficiency reaches 26-28%. Its capital cost is less than 1200 USD/kW, and its running cost is about 0.079 USD/kWh based on the biomass price of 35.7 USD/ton. There is a 20% increment on capital cost and 35% decrease on the fuel consumption compared to that of a 1 MW system without a combined cycle. Because only part of the project has been performed, many of the tests still remain and, accordingly, must be reported at a later opportunity.

环戊二烯基轻稀土氯化物的合成及其稳定性的研究

I LnCl_3-LiCl-THF配合物的研究深入地研究了氯化稀土和氯化锂于四氢呋喃溶液中，以不同的摩尔比，在不同条件下的反应。实验结果表明，反应速度随着稀土元素原子半径的减小，LiCl/LnCl_3摩尔比的增大，以及四氢呋喃用量的增加而加快。通过紫外质谱元素分析和X-射线单晶结构分析等证明，随着不同的LiCl/LnCl_3摩尔比和结晶条件的不同，可以得到不同组成的LnCl_3-LiCl-TNF配合物。对(LaCl)(THF)_2(μ_2-Cl)_4[Li(THF)_2]_2和(LaCl)DME(μ_3-Cl)(μ_2-Cl)_5(La·DME)Li(THF)_2晶体的结构分析表明，前者为单斜晶系，P21/C空间群。a=10.542(4), b=32.236(4), c=11.182(6)A °; β=113.50(3) °, V=3484.97 A °~3. Z=4, R=0.0471；后者为三斜晶系，PT空间群，晶胞参数是：a=11.123(3), b=16.564(5), c=8.653(3)A °;α=95.16(3), β=95.63(3), γ=74.71(3) °;V=1527.0A °~3。Z=2，R=0.0303。实验结果还表明，μ_2-和μ_3-氯桥键是LnCl_3-LiCl-THF类配合物中最基本、最重要的配位键，这种键是通过多重键的方式起着稳定分子结构的作用。当进行与有机配体的交换反应时，由于它们的特殊稳定性，能起到阻止轻稀土有机配合物歧化反应的作用。II环戊二烯基轻镧系氯化物的合成及其稳定性的研究对(G_5H_5)_3Ln·THF和LnCl_3·3LiCl-THF (Ln=La, Nd)溶液反应的研究表明，由于μ_2-氯桥键的作用，轻稀土环戊二烯基化合物中环戊二烯基的再分配反应，在0℃或室温下都能迅速进行。通过两者不同的摩尔比反应，经元素分析、红外光谱、~1H NMR和质谱鉴定，方便地合成了C_5H_5 LnCl_2·2LiCl·5THF和(C_5H_5)_2LnCl.LiCl·nTHF (Ln=La, Nd)等配合物。这一结果表明(C_5H_5)_2LnCl.LiCl·nTHF配合物不仅能稳定地存在于THF溶液中，而且能在一定条件下析出结晶。对(C_5H_5)_2LaCl.LiCl·4THF的晶体结构测定表明，该晶体属于正交晶系，Pc2m空间群。a=12.306(4), b=23.056(6), c=26.701(11)A°; V=7575.81A°~3;而(C_5H_5)_2LaCl·LiCl(DME)_2THF晶体则属于六方晶系，a=12.967(4), b=12.967(4), c=24.108(10)A°;V=3510 A°~3。通过(G_5H_5)_3Ln·THF与LnCl_3·3THF (Ln=La, Nd)的反应进一步研究了轻稀土环戊二烯基氯化物的稳定性。经元素分析，红外光谱和晶体结构分析表明合成了[(η~5-C_5H_5)_4La_3Cl_5·3THF]_2·9THF和(C_5H_5)_2 NdCl·THF配合物，前者属于三斜晶系，P1空间群。a=11.690(3), b=11.750(5), c=18.433(6)A°; α=98.75(3), β=95.62(3), γ=118.92(2)°; V=2147.06 A°~3. Z=1, R=0.099。对环戊二烯基轻稀土氯化物的稳定性进行了较详细地讨论。结果表明，THF的用量和化合物的溶解度是影响产物组成的决定因素。当THF的量不足以溶解所生成的产物时，就会歧化成溶解度最大((C_5H_5)_3Ln·THF)和最小(LnCl_3·nTHF)的两种组分。反之，环戊二烯基轻稀土化合物(Ln=La, Nd)中环戊二烯基的再分配反应就能顺利进行。经元素分析和结构测定，在((C_5H_5)_3Nd·THF)和NdCl_3·LiCl-THF溶液的反应体系中，偶然分离得到了[(η~5-C_5H_5)_4Nd_4(μ_4-o)(μ_2-Cl)_8] [Li(DMP)_2THF]_2这一不合常规的化合物，其晶体属于正交晶系，Pna2,空间群a=19.010(7), b=23.231(6), c=14.180(4); V=6261.91 A°~3。Z=4, R=0.054。说明在一定条件下,μ-氧桥键也起到了稳定分子结构的作用。推测了各类环戊二烯基轻稀土氯化物在THF中的合成反应机理,在LiCl存在的反应体系中Ln cl cl Li桥键能与环戊二烯基发生交换反应;在(C_5H_5)_3Ln·THF和LnCl_3·3THF的反应体系中,首先存在着LnCl_3分子之间的互相作用，因而易于形成双核或多核配合物。这类配合物以晶体形式析出时，易于发生结构上的变化，即化合物的结晶形态与溶液中的形态不一定相同。探索了环戊二烯基烯丙基稀土化合物新的合成方法。找到了真空加热脱水制备氯化稀土的最佳条件，其产物纯度在97%以上。通过加入Co_3O_4/Wo_3催化助燃剂的方法，提高了测定稀土有机化合物中碳含量的准确性。

两栖爬行动物资源信息管理系统的研制与应用

本文介绍中科院昆明动物研究所研制的“两栖爬行动物资源信息管理系统”和用此系统建立的昆明动物研究所两栖爬行标本及中国两爬类物种分布信息库。

HIGH-QUALITY INGAP AND INGAP/INALP MULTIPLE-QUANTUM-WELL GROWN BY GAS-SOURCE MOLECULAR-BEAM EPITAXY

Using gas-source molecular beam epitaxy, we have obtained high-quality GaInP and (AlGa)InP epilayers lattice-matched to (100) GaAs substrates. All grown layers exhibited mirror-like surfaces. For a 1.7 mum thick Ga0.5In0.5P film, the Hall electron mobility was 3400 and 30,000 CM2/V. s at 300 and 77 K, respectively. The luminescence wavelength of (AlxGa1-x)InP samples ranged from 680 nm (for GaInP) to 590 nm (for AlInP) at room temperature, and from 644 to 513 nm at 77 K. The multiple quantum well (MQW) structure with well width of 40 angstrom showed strong luminescence intensity with wavelength of 647 nm (300 K) or 622 nm (80 K). The satellite peaks can be detected in double-crystal X-ray (DCXR) diffraction measurements of the MQW samples, which indicates the perfect structural periodicity.

高功率共振腔增强型光电探测器研究进展

共振腔增强型光电探测器(RCE-PD)作为一种新型光电探测器,具有高量子效率、高响应度和波长选择性等优点,成为目前光纤通信领域中最为重要的探测器之一.在数字和模拟光传输系统中,高功率探测器由于具有高信噪比、低插入损耗等优点,在国际上越来越受到重视.综述了这两种探测器的基本结构、发展状况,展望了其发展前景等.指出高功率共振腔增强型光电探测器将是今后最有发展前途的探测器.

光纤与波导器件的联接技术

文中就如何增大耦合效率和工艺容差的问题作了具体的分析，在此基础上，评述了现有的几种能够获得较低插入损耗的光纤和波导的固定联接技术。