生物滴滤塔去除高浓度H2S废气的模拟研究

以生物滴滤塔（BTF）去除高浓度H₂S废气为研究对象,建立了一维轴向扩散反应器模型和双基质生物降解反应动力学模型,通过比较单基质模型和双基质模型在不同H₂S入口浓度条件下的模拟结果和实验结果,验证了双基质模型的有效性和可行性,研究了生物膜中H₂S的动态去除过程,考察了BTF在不同液相H₂S浓度和空床停留时间条件下的除臭性能。研究表明,当生物膜表面H₂S浓度为7589.3 mg/m³ 时,生物膜中传质-生物降解过程需要0.75 s才能达到稳态;较厚的生物膜使得内扩散阻力增大,生物降解反应速率分布的不均匀性增大,O₂浓度对生物降解速率的影响将越来越显著;进气速度和喷淋浓度可显著影响BTF中H₂S的去除率。     

脱氮生物滴滤塔中甲醛和硫化物的脱除

在生物滴滤塔脱除NO的过程中,废水中的甲醛和S2-作为微生物的营养物质被脱除。研究了S2-、甲醛/S2-值及NO对甲醛脱除的影响;甲醛、甲醛/S2-值及NO对S2-脱除的影响。S2-对甲醛的脱除有促进作用,且甲醛的脱除率随甲醛/S2-值的减小而增加。NO抑制甲醛的脱除。NO和甲醛对S2-的脱除无影响。生物滴滤塔能同时有效的脱除NO、S2-和甲醛。     

An attempt to compare the performance of bioscrubbers and biotrickling filters for degradation of ethyl acetate in gas streams

This study presents a comparison of the efficiency of a bioscrubber and a biotrickling filter (BTF) for the removal of ethyl acetate (EA) vapour from a waste gas stream, under the same operating conditions. The maximum EA elimination capacity achieved in the bioscrubber was 550 g m^?3 h^?1 with removal efficiency higher than 96%. For higher EA loadings the bioscrubber was oxygen limited, which caused incomplete EA biodegradation. When pure oxygen was fed to the bioscrubber at a rate of 0.02 L min^?1, the bioscrubber recovered and could treat higher EA loadings without any oxygen limitation. The BTF achieved EA elimination capacity of 600 g m^?3 h^?1 with removal efficiency higher than 97% and the dissolved oxygen concentration remained substantially higher than in the bioscrubber. However, severe channelling and blockage of the spray nozzle occurred due to the excessive biomass growth. Overall, the bioscrubber system was easier to operate and control than the BTF, while an enhancement of the oxygen mass transfer in the bioscrubber could potentially increase its performance by up to three times. Copyright © 2005 Society of Chemical Industry     

用不对称二羟基化反应合成光学纯( )-(1R,2R)和(-)-(1S,2S)-1,2-二苯基-1,2-乙二胺

以（Ｅ）－１,２－二苯基乙烯为原料,经催化不对称二羟基化反应,生成相应的对映体纯１,２－乙二醇,再分别与甲基磺酰氯和叠氮钠作用,最后催化氢化,生成光学纯１,２－乙二胺,总产率７０％。     

Evaluation of the Effects of Ag,Cu, ZnO and TiO2 Nanoparticles on the Expression Level of Oxidative Stress-Related Genes and the Activity of Antioxidant Enzymes in Escherichia coli,Bacillus cereus and Staphylococcus epidermidis

Although the molecular response of bacteria exposed to metal nanoparticles (NPs) is intensively studied, many phenomena related to their survival, metal uptake, gene expression and protein production are not fully understood. Therefore, this work aimed to study Ag-NPs, Cu-NPs, ZnO-NPs and TiO₂-NPs-induced alterations in the expression level of selected oxidative stress-related genes in connection with the activity of antioxidant enzymes: catalase (CAT), peroxidase (PER) and superoxide dismutase (SOD) in Escherichia coli, Bacillus cereus and Staphylococcus epidermidis. The methodology used included: the extraction of total RNA and cDNA synthesis, the preparation of primers for selected housekeeping and oxidative stress genes, RT-qPCR reaction and the measurements of CAT, PER and SOD activities. It was established that the treatment of E. coli and S. epidermidis with NPs resulted mainly in the down-regulation of targeted genes, whilst the up-regulation of genes was confirmed in B. cereus. The greatest differences in the relative expression levels of tested genes occurred in B. cereus and S. epidermidis treated with TiO₂-NPs, while in E. coli, they were observed under ZnO-NPs exposure. The changes found were mostly related to the expression of genes encoding proteins with PER and CAT-like activity. Among NPs, ZnO-NPs and Cu-NPs increased the activity of antioxidants in E. coli and B. cereus. In turn, TiO₂-NPs had a major effect on enzymes activity in S. epidermidis. Considering all of the collected results for tested bacteria, it can be emphasised that the impact of NPs on the antioxidant system functioning was dependent on their type and concentration.     

(1R, 2S)-2-(3,4-二氟苯基)环丙胺的合成研究

替卡格雷是一种口服选择性小分子抗凝血药,不需要通过代谢激活,自身具有抗血小板活性。而(1 R,2 S)-2-(3,4-二氟苯基)环丙胺是合成替卡格雷的一个关键中间体。本文在文献报道的合成路线基础上进行优化,对其中关键步骤—不对称Corey-Chaykovsky环丙烷化反应进行了研究,并筛选出最优反应条件：以L-薄荷醇为手性辅剂、三甲基碘化锍盐为叶立德试剂、二甲亚砜和四氢呋喃为混合溶剂、温度为10~12 ℃、10 %的碘化亚铜为催化剂时,反应的收率为60.5 %;在此基础上以五步反应,20%的总收率合成(1 R, 2 S)-2-(3, 4-二氟苯基)环丙胺。     

(S)-1-(2-氯乙酰基)吡咯烷-2-甲腈的合成与表征

探讨了合成(S)-1-(2-氯乙酰基)吡咯烷-2-甲腈的新工艺路线,即以L-脯氨酸为原料,经N-氯乙酰化、羧基氨基化和酰胺脱水反应合成目标化合物。目标化合物及各中间体的结构采用1HNMR和MS进行了确定。此外,详细研究了反应条件的影响,得到了优化的反应条件。目标产物的总收率可达42.3%。该合成路线具有原料便宜易得、操作简单、条件温和等优点,具有很好的市场应用前景。     

NHD用于甲醇生产脱硫脱碳的技术进展

阐述了甲醇生产中NHD法脱硫脱碳的技术进展,脱硫工序针对原料气含硫量不同,分别采用三塔流程配两级闪蒸和二塔流程配两级闪蒸,脱碳工序采取设计节能流程工艺、新型常解气提塔及改变气提方式等措施。实践证明,NHD工艺用于甲醇生产,更具高效节能的特点。     

Experimental study on the effect of H2S and SO2 on high temperature corrosion of 12Cr1MoV

Aiming at the high temperature corrosion in a coal-fired boiler, the effect of H₂S and SO₂ on the corrosion of 12Cr1MoV under the water wall condition has been investigated by experiments. The results indicate that H₂S can promote the corrosion significantly, and the coarse porous oxide film formed cannot stop the progress of corrosion. While SO₂ presents little effect on the corrosion. The main composition of the surface of 12Cr1MoV corrosion products is Fe₂O₃. With H₂S in the atmosphere, the corrosion gradually develops into deeper layers by forming FeS, FeO and Fe₂O₃ alternately. The corrosion rate is doubled for every 50 °C increase in temperature at 400–500 °C.     

手性相转移催化剂的合成及其不对称诱导效应Ⅰ——(1S,2R)-(一)-(1-对硝基苯基-1,3-二羟基-2-丙基)三甲基碘化铵

以氯霉素为原料,经水解、叔胺化、季铵化合成了光学纯(1S,2R)-(-)-(1-对硝基苯基-1,3-二羟基-2-丙基)三甲基 碘化铵,作为相转移催化剂,它对苯乙腈的α-甲基化、苯甲醛与氯仿的亲核加成均显示良好的催化作用和一定的不对称 诱导效应。     

S_2O_8~(2-)/ZrO_2-Al_2O_3-TiO_2固体超强酸的制备及催化活性研究

本文采用单因素实验法,研究了固体超强酸催化剂S2O82-/ZrO2-Al2O3-TiO2的制备工艺。结果表明,S2O28-/ZrO2-Al2O3-TiO2的最佳制备条件为:n(Zr)∶n(Al)∶n(Ti)=1∶3∶1,(NH4)2S2O8浸渍液浓度0.5mo.lL-1,浸渍时间2h,焙烧温度300℃,焙烧时间6h。此外,用红外光谱对固体酸进行了结构表征,以乙酸正丁酯的酯化反应对其酸催化活性进行了初步研究。     

The intermolecular interaction studies in the complexes of isothiocyanic acid (HNCS) and its derivatives with H2S: a computational study

The computational investigations are carried out on the complexes of isothiocyanic acid (HNCS) and its derivatives with H₂S through MP2/aug-cc-PVTZ//MP2/aug-cc-PVDZ level. Five, four, three and four structures are located on the potential energy surface of the HNCS?H₂S, HSCN? H₂S, HCNS? H₂S and HSNC?H₂S heterodimers, respectively. The calculated results reveal that the most stable heterodimers among all heterodimers obtained for the HNCS?H₂S, HSCN?H₂S, HCNS?H₂S and HSNC?H₂S systems belong to HSCN?H₂S system. Therefore, HSCN?H₂S system has a key role in the atmosphere.     

(S)-1-(四氢呋喃-2-基)乙酮合成工艺改进研究

(S)-四氢呋喃-2-甲酰胺与二氯亚砜-二甲基甲酰胺进行脱水反应得(S)-四氢呋喃-2-甲腈,然后与甲基氯化镁反应得(S)-1-(四氢呋喃-2-基)乙酮的油状物粗品,与亚硫酸氢钠加成,再经盐酸处理后得高纯度的(S)-1-(四氢呋喃-2-基)乙酮,总收率达68%。     

Enzymatic synthesis of (R)- and (S)-2-cyclohepten-1-ol

The synthetically useful chiral synthons, (R)- and (S)-2-cyclohepten-1-ol, can be prepared by an enantioselective transesterification of racemic trans-2-(phenylseleno) cycloheptanol using lipases, followed by selenoxide elimination and hydrolysis.