Advanced Materials Research Vols. 805-806

Abstract: Acquisition of lipids mainly in a form of triacylglycerol from microalgae is a potential way for biofuels production. Many unicellular microalgae make little triacylglycerol under favorable growth condition, but accumulate large amounts of it under environmental stress conditions (e.g., nutrient depletion, high light). In this paper, the green microalgae Chlamydomonas reinhardtii BAFJ5 was used as a model to study production of lipid bodies (LBs) which are important lipid storage organelles, particularly under stress. We discovered LBs accumulated dramatically when cells were grown in nitrogen-deplete medium. Using fluorescent microscopy and confocal laser scanning microscopy, intracellular LBs can be successfully visualized. The number and size of LBs were also quantified.

Abstract: The effect of nickel ions on the anaerobic digestion of phragmites australis and cow dung were investigated in batch experiments. Five levels of nickel ions were set as 0, 0.2, 0.8, 1.4 and 2.0 mg Ni/L. The results indicated that anaerobic digestion started on about 3^rd day 26 days of anaerobic digestion, the highest cumulative biogas was 32.70 mL/g·TS^-1 when nickel concentration was 0.8 mg Ni/L. The nickel ions in certain concentration range significantly affected biogas production rate, and effectively shorten reactor startup period. Biogas which was produced from phragmites combined with cow dung provided a new insight for bioenergy production whose process can be promoted by nickel ions addition.

Abstract: Henan Yima low rank coal is used to simulate the formation condition of coal biogenic methane in this paper. This experimental study is the impact of temperature, salinity, pH, Eh, trace elements, coal quality and coal rank on bio-methane concentration. Then this paper use analytic hierarchy process (AHP) to study the impact of the size of different factors on biological methane concentration on quantitative, which shows pH is the most important influence factors and the influence degree of different factors is pH, trace elements, coal quality, coal rank, salinity, temperature and Eh.

Abstract: Rice husk was subjected to slow and fast pyrolysis under different reaction conditions, to investigate the effects of several pyrolysis factors on the physicochemical properties of the rice husk chars, including the pyrolysis heating rate, cooling rate and resident time. The results indicated that the char yield did not show great changes during the slow pyrolysis process, while it was gradually decreased along with the resident time during the fast pyrolysis process. With the elevating of the pyrolysis conditions, the carbon content of the chars was increased monotonically, while the oxygen content was decreased. Moreover, the rice husk and its chars greatly differed in their functional groups, resulting from various decompositon, decarbonylation and aromatization reactions during the pyrolysis process.

Abstract: The catalyst prepared using the AC as support showed remarkably improvement of reaction performance. The improvement of the reaction performance obtained for the AC is probably ascribed to the physical structure and surface chemistry of AC. The support and corresponding catalyst are characterized by N₂ adsorption. Catalytic performance of the catalyst during FT synthesis was excellent. Syngas conversion was about 74%, whereas methane selectivity was low (~2 %).

Abstract: Biomass energy is considered to be an ideal renewable alternative energy and herbaceous energy plants as an important biomass resources became research hot spot all over the world. Switchgrass (Panicum virgatum L.) is international recognized as the most suitable bioenergy plant for the past few years. In order to obtain the basic data about seed germination characteristics on switchgrass as a bioenergy grass, different temperatures are investigated to select reliability indexes on seed germination of two species switchgrass from eight measurement indexes and then analyzed main factors influencing seed vigor by a principal component analysis. The result showed that co-efficiency of germination (CG), germination index (GI) and Peak value (PV) from eight germination indexes can be used as measurement indexes for detect seed germination of two species switchgrass.

Abstract: The fundamental principle and kinetic models of biomass pyrolysis are introduced, and the progress of studies on dynamic models for biomass pyrolysis is summarized in this paper in order to provide the theoretical basis for the development of biomass pyrolysis.

Abstract: Styrax confusus Hemsl., a promising energy plant, was used as raw material for biodiesel preparation in this paper. The transesterification was catalyzed by magnetic catalyst S₂O₈^2--ZrO₂/Fe₃O₄, prepared by chemical co-precipitation method. TEM images indicat that the average particle diameter of magnetic core Fe₃O₄ and catalyst carrier ZrO₂/Fe₃O₄ are 5-20 nm and 30-50 nm respectively. Because of its unique porous structure the BET surface area could up to 140.75 m²/g. The results show that a best catalytic activity is obtained when the solid catalyst impregnated in 2.5 mol·L^-1 (NH₄)₂S₂O₈, calcined at 400 °C for 3 h, and a high methyl ester yield could be obtained under the optimal reaction conditions of catalyst amount 4.5 % (wt/wt oil), molar ratio of methanol/oil 6:1, reaction temperature 65 °C and time 2.0 h.

Abstract: During biomass combustion, alkali metals are partly released to the gas phase and form low melting point compound, which may enrich to the heat exchangers and cause heavy sinters in the incinerator. The aim of this study is to obtain quantitative data on the migration of sodium by measuring the content of sodium remained in the combustion products using AAS. Three groups of biomass ashes were produced respectively to investigate the influence of combustion temperature, fuel thickness and kaolin addition. The results indicate that, rising temperature enhances Na release from the biomass to the gas phase, while increasing the fuel thickness does the opposite. The reaction of kaolin and Na to generate a high melting point material inhibits the migration of Na, which reduces the biomass sintering in the incinerator.

Abstract: In the present study, the Acetyl-coenzyme A carboxylase (ACCase) of Chlorella sp. USTB-01 purified and characterized. Molecular weight of ACCase was calculated to be about 456 kD and was comprised of two identical subunits of 229 kD. The enzymatic characteristics isoelectric point was 6.7. Moreover, a rapid and sensitive assay of High performance liquid chromatography (HPLC) was established to measure overall activity of ACCase in low protein content condition by detect the ACCase activity by measuring ADP production and Acetyl-coenzyme A (Acetyl-CoA).