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The catalytic effects of activated alumina (Al(2)O(3)) on the pyrolysis of Miscanthusxgiganteus, a new energy crop, were investigated. Catalytic pyrolysis experiments carried out under static and nitrogen atmospheres were performed in a fixed-bed reactor. The final pyrolysis temperature was kept constant at 550 degrees C in all of the experiments. The effect of catalyst loading (by weight of feedstock as 10%, 20%, 40%, 60%, 80% and 100%), heating rate (10 degrees C and 50 degrees Cmin(-1)), nitrogen flow rate (50, 100, 150 and 200cm(3)min(-1)) on the pyrolysis conversion and product yields were investigated. The results were compared with those obtained in non-catalytic pyrolysis. Activated alumina catalyst has a strong influence on the Miscanthusxgiganteus pyrolysis product and conversion yield. Furthermore, the catalytic bio-oils obtained from catalytic pyrolysis under static and nitrogen atmospheres were examined using elemental analysis, column chromatography, Fourier transform infrared (FTIR) and nuclear magnetic resonance ((1)H NMR) spectroscopy methods. 相似文献
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The evolution of the Sabin strain of type 1 poliovirus in a hypogammaglobulinemia patient for a period of 649 days is described. Twelve poliovirus isolates from sequential stool samples encompassing days 21 to 649 after vaccination with Sabin 1 were characterized in terms of their antigenic properties, virulence in transgenic mice, sensitivity for growth at high temperatures, and differences in nucleotide sequence from the Sabin 1 strain. Poliovirus isolates from the immunodeficient patient evolved gradually toward non-temperature-sensitive and neurovirulent phenotypes, accumulating mutations at key nucleotide positions that correlated with the observed reversion to biological properties typical of wild polioviruses. Analysis of plaque-purified viruses from stool samples revealed complex genetic and evolutionary relationships between the poliovirus strains. The generation of various coevolving genetic lineages incorporating different mutations was observed at early stages of virus excretion. The main driving force for genetic diversity appeared to be the selection of mutations at attenuation sites, particularly in the 5' noncoding region and the VP1 BC loop. Recombination between virus strains from the two main lineages was observed between days 63 and 88. Genetic heterogeneity among plaque-purified viruses at each time point seemed to decrease with time, and only viruses belonging to a unique genotypic lineage were seen from day 105 after vaccination. The relevance of vaccine-derived poliovirus strains for disease surveillance and future polio immunization policies is discussed in the context of the Global Polio Eradication Initiative. 相似文献
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Powdered activated carbon added biological treatment of pre-treated landfill leachate in a fed-batch reactor 总被引:3,自引:0,他引:3
Biological treatment of landfill leachate usually results in low treatment efficiencies because of high chemical oxygen demand (COD), high ammonium-N content and also presence of toxic compounds such as heavy metals. A landfill leachate with high COD content was pre-treated by coagulation-flocculation followed by air stripping of ammonia at pH = 12. Pre-treated leachate was biologically treated in an aeration tank operated in fed-batch mode with and without addition of powdered activated carbon (PAC). PAC at 2 g l–1 improved COD and ammonium-N removals resulting in nearly 86% COD and 26% NH4-N removal. 相似文献
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A method was developed for the measurement of the bacterial particle conductivity, based on the measurement of the conductivity of a bacterial cell suspension sigma(s) and the suspending medium sigma(m). A line plotted through sigma(s) - sigma(m) versus sigma(m) crosses the x-axis at sigma(m) = sigma(p), independent of the bacterial cell concentration. The method does not require anything more complex than a centrifuge and a conductivity meter. Knowledge of the bacterial particle conductivity is of importance in, for example, the dielectrophoretic separation, manipulation and trapping of bacterial cells, as well as the study of their physiological state. 相似文献
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Ian Sofian Yunus Amaury Cazenave-Gassiot Yu-chi Liu Ying-Chen Lin Markus R Wenk Yuki Nakamura 《Plant signaling & behavior》2015,10(8)
Phospholipids are the crucial components of biological membranes and signal transduction. Among different tissues, flower phospholipids are one of the least characterized features of plant lipidome. Here, we report that floral reproductive organs of Arabidopsis thaliana contain high levels of phosphatidic acid (PA), a known lipid second messenger. By using floral homeotic mutants enriched with specific floral organs, lipidomics study showed increased levels of PA species in ap3-3 mutant with enriched pistils. Accompanied gene expression study for 7 diacylglycerol kinases and 11 PA phosphatases revealed distinct floral organ specificity, suggesting an active phosphorylation/dephosphorylation between PA and diacylglycerol in flowers. Our results suggest that PA is a major phospholipid class in floral reproductive organs of A. thaliana. 相似文献
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[目的]探究新疆地震断裂带含硫冷泉泉水古菌群落组成及多样性.[方法]利用酶解法直接从冷泉泉水样品中提取环境总DNA,采用古菌通用引物对16S rRNA基因进行扩增,构建16S rRNA基因克隆文库,通过Alu Ⅰ和AfaⅠ两种限制性内切酶对随机挑选的115个阳性克隆子进行酶切分型,将不同酶切带型对应的克隆子送样测序,测序结果与GenBank序列进行比对并构建16S rRNA基因系统发育树.[结果]古菌克隆文库中共得到44个不同的酶切带型,BLAST序列比对和系统发育分析将它们划分于广古菌门(Euryarchaeota,94.78%)和奇古菌门(Thaumarchaeota,4.35%).奇古菌门克隆与Nitrosopumilus.sp序列相似性达到了93%;而广古菌门类群较为多样,其中,42.61%的克隆子属于RC-V cluster,20.87%与13.91%的克隆子分别属于LDS cluster和Methanomicrobiales,4.35%的克隆子与甲烷厌氧氧化相关的类群(ANME-1a-FW)具有较高的的相似.另外,13.05%的克隆子属于广古菌门中的未知类群.[结论]乌鲁木齐10号泉水体中广古菌类群多样,可能蕴藏有大量潜在的古菌新类群. 相似文献
100.
Maarof Manira Khairoji Khairul Anuar Wan Tai Seet Abd Wahab Ahmad Irfan Min Hwei Ng Kien Hui Chua Mohd. Yunus Mohd Heikal Bin Saim Aminuddin Bt Hj Idrus Ruszymah 《Cell and tissue banking》2014,15(1):41-49
Animal-derivative free reagents are preferred in skin cell culture for clinical applications. The aim of this study was to compare the performance and effects between animal-derived trypsin and recombinant trypsin for skin cells culture and expansion. Full thickness human skin was digested in 0.6 % collagenase for 6 h to liberate the fibroblasts, followed by treatment with either animal-derived trypsin; Trypsin EDTA (TE) or recombinant trypsin; TrypLE Select (TS) to liberate the keratinocytes. Both keratinocytes and fibroblasts were then culture-expanded until passage 2. Trypsinization for both cell types during culture-expansion was performed using either TE or TS. Total cells yield was determined using a haemocytometer. Expression of collagen type I, collagen type III (Col-III), cytokeratin 10, and cytokeratin 14 genes were quantified via RT-PCR and further confirmed with immunocytochemical staining. The results of our study showed that the total cell yield for both keratinocytes and fibroblasts treated with TE or TS were comparable. RT-PCR showed that expression of skin-specific genes except Col-III was higher in the TS treated group compared to that in the TE group. Expression of proteins specific to the two cell types were confirmed by immunocytochemical staining in both TE and TS groups. In conclusion, the performance of the recombinant trypsin is comparable with the well-established animal-derived trypsin for human skin cell culture expansion in terms of cell yield and expression of specific cellular markers. 相似文献