二次游离氧化钙测定条件

研究了测定熟料中二次游离氧化钙的条件。结果表明 :只要增大分析试样的细度 ,保证足够长的萃取时间 ,用甘油 乙醇法和乙二醇 乙醇法都能测定出熟料中的二次f CaO ,乙二醇 乙醇比甘油 乙醇萃取速度快。     

玉米原料酒精高浓度发酵中间试验的研究

以啤酒酵母菌种 (Saccharomyces cerevisie) Y316进行 10 0 0 L罐的酒精生产性中试。玉米粉的质量分数为 33.3% ,95℃下液化 1h,6 0℃糖化 1h,30℃保温发酵 (6 0～ 70 ) h。发酵醪产酒精 13.9%以上 ,残糖 1%以下 ,淀粉利用率 90 .5 %以上。     

The influence of inert solids on ethanol production by Saccharomyces cerevisiae

The catalytic role of various inert solid supports on acceleration of alcohol fermentation by Saccharomyces cerevisiae was investigated. The enhanced rate of alcohol production was dependent on the nature of the support as well as on the amount used. Among all the tested supports, chitosan flakes showed the maximum yield of alcohol (93% of theoretical yield). This higher rate of alcohol production was associated with the twofold increase in the activity of alcohol dehydrogenase over control. Our results suggest that the addition of a small fraction of solids in submerged fermentations to facilitate cell anchorage for enhanced metabolic activity is easier and more economical compared to cell immobilization processes. IICT Communication No. 4266. Some of the results in this article are covered under a patent.     

休哈塔假丝酵母发酵木糖产乙醇的研究

对休哈塔假丝酵母初始菌株经过驯化筛选出一株TZ-8高产酒精菌株,研究了木糖初始浓度、温度、转速以及pH值对TZ-8菌株发酵产乙醇的影响,实验结果表明,最适发酵条件是木糖初始浓度为40 g/L,温度为30℃,转速90~110 r/min,初始pH4.5~5.0,乙醇产量为11.02 g/L,木糖利用率达到86.9%.     

纤维质燃料水平填充床反向阴燃传播特性研究

基于两步反应动力学机理(包括燃料热解和燃料的氧化),建立了二维非稳态燃料填充床阴燃的数学模型.该模型既考虑了固相和气相之间的热传递,也考虑到了气体在多孔介质内扩散系数的变化.辐射换热采用扩散近似方式予以表达.数值模拟结果表明:阴燃传播速度随着来流速度的增大而增大,但当来流速度超过0.35 cm/s时,阴燃速度增长幅度大大减小;来流速度对阴燃最高温度影响不大.同时还模拟了燃料阴燃过程中气体组分(O2、CO、CO2及H2O)和固体成分(燃料、焦炭)的变化以及温度分布情况.图8,表2,参12.     

Adsorption and reactions of ethanol on Mo2C/Mo(1 0 0)

The adsorption, desorption and dissociation of ethanol have been investigated by work function, thermal desorption (TPD) and high resolution electron energy loss (HREELS) spectroscopic measurements on Mo₂C/Mo(1 0 0). Adsorption of ethanol on this sample at 100 K led to a work function decrease suggesting that the adsorbed layer has a positive outward dipole moment By means of TPD we distinguished three adsorption states, condensed layer with a Tp = 162 K, chemisorbed ethanol with Tp = 346 K and irreversibly bonded species which decomposes to different compounds. These are hydrogen, acetaldehyde, methane, ethylene and CO. From the comparison of the Tp values with those obtained following their adsorption on Mo₂C it was inferred that the desorption of methane and ethylene is reaction limited, while that of hydrogen is desorption limited process. HREEL spectra obtained at 100 K indicated that at lower exposure ethanol undergoes dissociation to give ethoxy species, whereas at high exposure molecularly adsorbed ethanol also exists on the surface. Analysis of the spectral changes in HREELS observed for annealed surface assisted to ascertain the reaction pathways of the decomposition of adsorbed ethanol.     

Improved Self-Feedback Gain in the Context Layer of a Modified Elman Neural Network

The use of a range of values for the self-feedback gains in the context layer of a modified Elman neural network is shown to reduce RMS error when modelling a non-linear dynamic system.     

Effects of P content in a P/HZSM-5 catalyst on the conversion of ethanol to hydrocarbons

A series of P/HZSM-5 catalysts prepared by impregnation method were used for ethanol conversion to lower olefins. The catalysts were characterized by X-ray diffraction (XRD), NH3-temperature-programmed desorption (NH3-TPD) and N2 adsorption-desorption measurements. It was found that the P/HZSM-5 catalysts showed high activity and selectivity toward light olefins. The selectivities of propylene and butylene can be improved with the introduction of phosphorus (P). When the content of P reached 3.0 wt%, more than 18.9% propylene in the gaseous products was obtained over the P/HZSM-5 catalyst at 450 ?C. The introduction of P modified the strong Br?nsted acid sites of the original HZSM-5 catalysts and P/HZSM-5 catalysts could resist coke formation and showed good stability.     

乙醇与血细胞相互作用过程及机理研究

用激光诱导荧光光谱技术研究了重度酒精中毒全血溶液的光谱特性,得到了光谱特征的变化规律,分析了乙醇在生物体内的代谢过程,以及乙醇对血细胞的作用机理.结果表明：重度酒精中毒全血溶液的荧光强度随时间衰变表现出明显的规律性,分析认为酒精作用于血细胞引起血液粘滞性以及血红细胞体积的增大,最终导致荧光强度的规律变化.研究结果对乙醇与生物组织特别是细胞的相互作用及其机理研究具有一定的参考意义.     

Solubility behavior of amphiphilic block and random copolymers based on 2‐ethyl‐2‐oxazoline and 2‐nonyl‐2‐oxazoline in binary water–ethanol mixtures

The solution properties of random and block copolymers based on 2‐ethyl‐2‐oxazoline (EtOx) and 2‐nonyl‐2‐oxazoline (NonOx) were investigated in binary solvent mixtures ranging from pure water to pure ethanol. The solubility phase diagrams for the random and block copolymers revealed solubility (after heating), insolubility, dispersions, micellization as well as lower critical solution temperature (LCST) and upper critical solution temperature behavior. The random and block copolymers containing over 60 mol % pNonOx were found to be solubilized in ethanol upon heating, whereas the dissolution temperature of the block copolymers was found to be much higher than for the random copolymers due to the higher extent of crystallinity. Furthermore, the block copolymer containing 10 mol % pNonOx exhibited a LCST in aqueous solution at 68.7 °C, whereas the LCST for the random copolymer was found to be only 20.8 °C based on the formation of hydrophobic microdomains in the block copolymer. The random copolymer displayed a small increase in LCST up to a solvent mixture of 9 wt % EtOH, whereas further increase of ethanol led to a decrease in LCST, which is probably due to the “water‐breaking” effect causing an increased attraction between ethanol and the hydrophobic part of the copolymer. In addition, the EtOx‐NonOx block copolymers revealed the formation of micelles and dynamic light scattering demonstrated that the micellar size is increasing with increasing the ethanol content due to the enhanced solubility of EtOx. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 515–522, 2009