Advanced Materials Research Vols. 608-609

Abstract: Fuel ethanol production from lignocellulosic biomass corn stover was investigated. Compared with acid pretreatment and ammonia steeping pretreatment, alkali pretreatment with 2% NaOH markedly enhanced lignin removal and thereby improved the enzymatic hydrolysis yield to 81.2% by 48 h. Fed-batch hydrolysis was started with a batch hydrolysis containing 80 g/l substrate, with cellulosic residue added at 6 and 12 h twice to get a final substrate concentration of 110 g/l. After 72 h of hydrolysis, the reducing sugar concentration reached 89.5 g/l with a hydrolysis yield of 83.3%. Further fermentation of the cellulosic hydrolysate containing 56.7 g/l glucose and 23.6 g/l xylose was performed using a recombinant yeast strain Saccharomyces cerevisiae ZU-10, and 36.3 g/l ethanol was produced within 72 h. The research results are meaningful in fuel ethanol production from renewable lignocellulosic biomass.

Abstract: The present work aims at decentralization of sewage treatment and eco-efficient way of enabling the deployment of residential digesters to treat only the water with high organic load without overloading the system, avoiding the drag of sludge and effluent untreated into the urban network of collection. For this purpose we developed a low-cost technology that treats sewage in the house of the citizen, thus avoiding that large stations aerobic treatment of sewage and its result regarding the large demands for energy and area: the generation and disposal of biogas smelly collection networks in urban, high production and disposal costs aerobic sludge, the disposal of sewage in fresh water bodies causing eutrophication of waters and spread of diseases hydro transmitted. The system proposed digester residential removes about 80% of the organic load of sewage without the use of any electromechanical element, and also allows to collect the biogas produced subsequently be used for energy or simply be burned to hygiene and / or crediting of carbon . Basically, the system comprises three anaerobic digesters in upflow sludge bed, arranged in series forming cascade phase separator with solid-liquid gas-shaped coil. Used to treat wastewater with high organic load coming from the toilet and the kitchen sink. Then the waters with low organic load coming from the baths, sinks and laundry, are used to dilute and improve the quality end of the anaerobically treated effluent in a sustainable manner. Social and environmental technology developed aligns with the guidelines of the National Water Agency and the Kyoto Protocol, whose goal is to reduce greenhouse gases.

Abstract: Dilute sulfuric acid pretreatment of corn stover was used to obtain a solution of high concentration of xylose from the hemicellulosic fraction and a relatively low concentration of glucose, which not only saved the hemicellulase but also made a full use of corn stover. Then the study considered the selectivity (xylose-glucose ratio) as an important parameter to optimize the hydrolysis conditions. The results optimized by response surface methodology (RSM) showed that the optimum conditions for pretreatment were found to be H2SO4 concentration of 2.4% and reaction time of 100min at 100°C. Under these conditions, 78.8% of xylose yield was achieved and the glucose yield was lower than 11.6%. To confirm these results, the optimum condition was performed and the actual results of xylose yield and glucose yield were 78% and 11.3%.

Abstract: The characteristics of hot gas utilization are analyzed in the thesis and experiments on rice husk were done in 6 MW bubbling fluidized-bed positive pressure gasification system. The results showed that the positive rice husk gasification system can work well and no tar condensed on the pipes. As sensible heat of hot gas accounting for 11.7% of fuel, the method of hot utilization of fuel gas can make full use of gas energy.

Abstract: The intensive providing of gasified straw energy is an important way to make use of the straw energy. The thesis analyses the current situation of the intensive countryside straw-gasifying stations and problems such as lack of money, management, safety and precautions against pollution, and professional standards. It discuses the influence of intensive straw-gasifying on household energy consumption in the countryside, and based on that, it gives suggestion on how to enlarge financial investment, set up examine system and professional standards, enforce the technique innovation, establish supervision system and develop the straw-gasifying industry rapidly.

Abstract: Cell suspension cultures of Jatropha curcas were established and optimized in shake flasks. The stem segments of Jatropha curcas were taken as the explants for studying the techniques of callus induction and cell suspension cultures. The result shows that the optimal medium for callus induction is MS+2,4-D0.6mg/L+ BA1.0mg/L + Sucrose 30g/L, in which the callus is humid, loose and colorful. The fine suspension cell system have been established by inoculating the callus in the medium of MS+NAA0.2mg/L+2,4-D1.0mg/L+BA0.5mg/L for 13 days of cultivation, and the rotation speed should be lower than 120rpm in the culture of oscillation. QD-labeled chitosan-DNA complexes as nano transgenic system, using CdSe as bio-labels and chitosan-DNA(CS-DNA) as nano-scale genic carriers, were prepared and shown to have uniform particle sizes and superior fluorescence properties. Confocal laser scanning microscopy(CLSM) confirmed the target DNA from QD-labeled chitosan-DNA complexes was integrated into the plant cell and suggest the possibility of stable transformation in Jatropha curcas.

Abstract: The paper adopts the NW-DMBR to treat the domestic wastewater; examines the stability of the operation and analyzes the effect of organic loading of inflow, sludge loading, hydraulic retention time, dissolved oxygen and pH on the stability. The purpose is about obtaining the best parameters through the system operation from the experiments and providing the main references for the application in engineering.

Abstract: Biodiesel is one of the most important substitutes for diesel oil. This work reports the use of near Infrared Spectroscopy (NIR) to estimate the kinematic viscosity value of biodiesel-diesel blends. Partial least squares models were developed using data of different spectra regions and different pre-processing methods were employed for developing the calibration models. The results indicate that NIR can be used in biodiesel-diesel blends properties detecting.

Abstract: three oil extraction ways of microwave assisted, conventional and high-pressure oil extraction are compared, we select the high-pressure as the aqueous oil extraction method to carry on the experimental study of the relevant technology and discuss the solid-liquid ratio, baking time, baking temperature, pH value and high-pressure steam processing time on oil yield.

Abstract: In order to hydrolyze corn gluten meal efficiently, combinations of two or three out of three hydrolysis enzymes (protex6L, protex7L and papain) were used and the process parameters were optimized in this paper. The degree of hydrolysis of corn gluten meal was assayed by using pH-stat method. The ratio of enzymes was optimized and the effect of multi-enzyme hydrolysis was compared with that of single-enzyme hydrolysis. The result showed that the optimal ratio of protex6L and protex7L was 3:1, protex6L and papain was 6:5, protex7L and papain was 1:1, and the optimal ratio of protex6L, protex7L and papain was 4:1:1.The degree of hydrolysis and soluble protein content of multi-enzyme hydrolysis and single-enzyme hydrolysis were approximately equal, but multi-enzyme hydrolysis was timesaving.