原位预处理甘蔗糖蜜对耐高温酿酒酵母突变株Saccharomyces cerevisiae AQ生产乙醇的影响

【目的】探讨和分析原位预处理糖蜜促进酿酒酵母生长和乙醇生产的原因,开发一条绿色、低成本糖蜜乙醇生产途径。【方法】先在不同温度和初始糖浓度条件下,考察酿酒酵母原始菌株Saccharomyces cerevisiae A及其突变株Saccharomyces cerevisiae AQ的生长和乙醇生产性能差异,再以原位预处理前后糖蜜为发酵底物,测定突变株Saccharomyces cerevisiae AQ在不同培养基中的生长量、出芽率、乙醇产量、胞内超氧化物歧化酶(SOD)、过氧化物酶、细胞质内ATP酶和线粒体内ATP酶活力,研究原位预处理糖蜜对其生理特性的影响。【结果】在高温发酵糖蜜过程中,突变株Saccharomyces cerevisiae AQ较原始菌株Saccharomyces cerevisiae A表现出更好的生长和乙醇发酵稳定性。当以原位预处理糖蜜作为Saccharomyces cerevisiae AQ唯一碳源时,其胞内SOD酶、过氧化物酶、细胞质内ATP酶和线粒体内ATP酶活力较以糖蜜原料为唯一碳源时分别提高2.51倍,0.92倍,1.80倍和1.45倍,乙醇收率为31.07%,较以糖蜜原料为唯一碳源时提高36.26%。【结论】突变株Saccharomyces cerevisiae AQ较原始菌株Saccharomyces cerevisiae A更适用于糖蜜发酵生产乙醇体系,且新型的原位预处理方法能通过增强Saccharomyces cerevisiae AQ在糖蜜培养基中的呼吸作用,提高菌株活力,从而进一步提高乙醇收率。     

乙醇和邻苯二酚气相合成邻羟基苯乙醚的研究

采用不均匀沉淀法制备了二元组分Al1P1.30，三元组分Al1P1.30Si0.17，四元组分Al1P1.30Ti0.30Si0.17三个催化剂，并研究了邻苯二酚与乙醇在该催化剂上的气相O－乙基化反应。结果表明，在Al1P1.30Ti0.30Si0.17催化剂上，邻苯二酚转化率和目的产物收率分别约为94％和84％，并在反应100h内保持活性不衰减，展示了良好的应用前景。     

Ethanol metabolism in calluses of several selected plant species on two typical plant-growth-regulator balanced media

For investigation on the characteristics of ethanol metabolism in tissues of different plant species, calluses from eight selected plant species were cultured on medium supplemented with ethanol in tightly sealed culture flasks. Changes of the ethanol level were detected by gas chromatography. During the culture period, the calluses of tobacco, potato and petunia were, able to catabolize exogenous ethanol, resulting in the prominent decline of the ethanol level in the medium. The calluses of melon and peanut were also able to catabolize thanol but with lower efficiency. The other three calluses of carrot, soybean and rice did not catabolize ethanol but instead produced small to large amount of ethanol, resulting in the increase of the ethanol level in the media. It was also found that changing the balance between auxin and cytokinin could influence only the ethanol metabolism efficiency but could not change the metabolism patterns on ethanol of the cultured calluses. It can be concluded that, ethanol metabolism pattern of calluses in cultures is an innate physiological characteristic of the respective plant species. Foundation item: Supported by the Natural Science Foundation of Guangdong Province (No. 950406) Biography: Yang Yue-sheng (1957-), male, Professor, research direction: plant physiology and plant cell engineering.     

CS1 PLC在乙醇精馏控制系统中的应用研究

乙醇精馏控制系统是将纯度为95%的乙醇经三重精馏生成无水乙醇.本文采用OMRON公司CS1 PLC及其内置回路控制板与模拟量单元构建过程控制系统,利用CX-Process Tool 软件完成模块流程图组态后下载到回路控制板中运行,实现了对精馏塔温度、液位及流量的自动控制.结果表明:该系统使用方便,具有良好的动态调整性能,极大提高了系统的稳定性、可靠性.     

Inhibitive effect of Xylopia ferruginea extract on the corrosion of mild steel in 1M HCl medium

The alkaloid content of the leaves and stem bark of Xylopia ferruginea plant was isolated and tested for its anticorrosion potential on mild steel corrosion in a hydrochloric acid medium by using electrochemical impedance spectroscopy,potentiodynamic polarization measurement,scanning electron microscopy(SEM),and Fourier transform infra red(FTIR) analysis.The experimental results reveal the effective anticorrosion potential of the plant extract.The mixed mode of action exhibited by the plant extract is evidenced from the polarization study.SEM images proof the formation of a protective layer over the mild steel surface,and this is supported by the FTIR study.The possible mode of the corrosion inhibition mechanism has also been discussed.     

SnO2纳米晶的溶胶-凝胶法制备及气敏性质

采用溶胶 -凝胶法制备出 Sn O2 纳米晶材料 .经 X光衍射和透射电镜研究表明 ,该材料具有金红石结构 ,晶粒为球形 ,粒径约 4nm.气敏特性研究表明 ,该材料具有很好的乙醇敏感特性     

酿酒酵母高产菌株的木薯酒精产业化生产试验

【目的】对酿酒酵母高产菌株Ygxas-49木薯酒精产业化应用进行试验。【方法】先在200t发酵罐进行分批发酵,对该菌株的各个发酵指标进行评估,再将可行的方案进一步放大至年产12万t酒精生产线上进行生产稳定性试验,最后为考察该菌在产业化应用上的潜力,在200t发酵罐进行高浓度酒精发酵试验。【结果】200t发酵罐分批发酵结果表明:与生产对照菌株相比,酒度提高8.92%,发酵时间减少12h以上,其他发酵指标基本相同。采用该菌株生产酒精可以提高酒度,大大节约发酵时间,增加设备利用率,从而降低酒精生产成本。12万t酒精生产线稳定运行30d结果表明:与生产对照菌株相比,酒度提高5.35%,发酵时间减少10h以上,其他发酵指标基本相同。200t发酵罐高浓度酒精发酵结果:酒度为15.1%(V/V),发酵时间为56h,与目前文献报道最高生产水平(酒度13.5%,V/V;发酵时间69h)相比,酒度提高11.85%,发酵时间缩短13h。【结论】Ygxas-49菌株应用于工业化生产,各项工艺指标均显著优于国内目前最高水平,具有良好的工业化应用前景。     

汽油机燃用乙醇汽油的试验研究

在国内外已有的研究基础上,基于我国国情和现有的使用情况,选用摩托丰汽油机和电喷机,测试乙醇汽油对这两种汽油机的排放、动力性和油耗的影响．试验结果表明：与无铅汽油相比,能明显降低发动机CO和HC的排放,对NO_x排放影响变化趋势并不单一,但是从整体情况来看,NO_x排放又有所降低;电喷机燃用乙醇汽油随乙醇量增大,尾气排放的三种主要污染物有明显下降;摩托车汽油机燃用乙醇汽油总油耗率高于普通无铅汽油3%～5%左右。     

不同反应物和工艺条件对CeO2/ZrO2复合纳米粉末性能的影响

分别采用ZrOCl2·8H2O、CeCl3·7H2O和ZrOCl2·8H2O、CeO2、HCl两类不同反应物,利用共沉淀法制备了氧化铈摩尔含量为12%的氧化铈/氧化锆复合纳米粉末.分析了实验过程中沉淀物未经醇洗和经过醇洗、常规干燥及微波干燥等不同工艺条件对所得复合粉料性能的影响.通过透射电镜(TEM)对粉末形貌及粒径观察和测定,以及X射线衍射法(XRD)对粉末的物相分析,表明以ZrOCl2·8H2O和CeCl3·7H2O为反应物所得凝胶,经过醇洗及微波干燥的方法可以得到21 nm左右且均匀性和分散性好的球形颗粒.     

乙醇羰化Ni-Sn/C催化剂失活机理的研究

探讨了乙醇羰化反应活性较高的Ni Sn/C催化剂的稳定性及失活机理 ,并利用俄歇电子能谱 (AES)和扫描电子显微镜 (SEM )等方法对催化剂进行了表征 .结果表明 ,催化剂在高于反应条件温度及长时间反应条件下 ,由于Sn易于富集在催化剂表面上 ,导致积碳效应 ,堵塞催化剂孔道 ,从而使具有活性的Ni0 活性中心数量减少 ,使催化剂活性降低