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1.
The pyrolysis reactions of soybean oils have been studied. The pyrolytic products were analyzed by GC–MS and FTIR and show the formation of olefins, paraffins, carboxylic acids and aldehydes. Several kinds of catalysts were compared. It was found that the amounts of carboxylic acids and aldehydes were significantly decreased by using base catalysts such as Na2CO3 and K2CO3. The low acid value pyrolytic products showed good cold flow properties and good solubility in diesel oil at low temperature. The results presented in this work have shown that the pyrolysis of soybean oils generates fuels that have chemical composition similar to petroleum based fuels. 相似文献
2.
Novel carbon materials have been prepared by the carbonization of acrylonitrile (AN)/divinylbenzene (DVB) suspension porous copolymers having nominal crosslinking degrees in the range of 30-70% and obtained in the presence of various amounts of porogens. The carbons were obtained by pre-oxidation of AN/DVB copolymers at 250-350°C in air followed by pyrolysis at 850°C in an N(2) atmosphere. Both processes were carried out in one furnace and the resulting material needed no further activation. Resulting materials were characterized by XPS and low temperature nitrogen adsorption/desorption. It was found that maximum pyrolysis yield was ca. 50% depending on the oxidation conditions but almost independent of the crosslinking degree of the polymers. Porous structure of the carbons was characterized for the presence of micropores and macropores, when obtained from highly crosslinked polymers or polymers oxidized at 350°C and meso- and macropores in all other cases. The latter pores are prevailing in the structure of carbons obtained from less porous AN/DVB resins. Specific surface area (BET) of polymer derived carbons can vary between 440 m(2)/g and 250 m(2)/g depending on the amount of porogen used in the synthesis of the AN/DVB polymeric precursors. 相似文献
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Structural characterization of monophosphoryl lipid A homologs obtained from Salmonella minnesota Re595 lipopolysaccharide 总被引:3,自引:0,他引:3
R S Johnson G R Her J Grabarek J Hawiger V N Reinhold 《The Journal of biological chemistry》1990,265(14):8108-8116
Sixteen monophosphoryl Lipid A (MLA) homologs obtained from the lipopolysaccharides of Salmonella minnesota Re595 were separated by preparative thin layer chromatography into eight fractions. The components of these fractions were analyzed directly (or as structural analogs) and characterized by mass spectrometry. Molecular weights were determined by negative and positive ion fast atom bombardment mass spectrometry and component structures were assigned following a study of fragmentation and metastable ion kinetic energy spectrometry. One fraction (TLC-8) contained a single heptaacyl MLA of Mr = 1,954, a structure previously elucidated (Qureshi, N., Mascagni, P., Ribi, E., and Takayama, K. (1985) J. Biol. Chem. 260, 5271-5278). The remaining seven fractions contained 15 additional MLAs with decreasing acylation. Two of these components have been previously reported in S. minnesota and Salmonella typhimurium. Three of the eight TLC fractions (TLC-8, -7, -6) were found to be biologically active toward human platelets inducing their aggregation and secretion of serotonin. All tested fractions induced varying degrees of phosphorylation of a platelet protein of Mr = 47,000 (P47) reflecting protein kinase C activation (Grabarek, J., Her, G. R., Reinhold, V. N., and Hawiger, J. J. (1990) J. Biol. Chem. 265, 8117-8121). 相似文献
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Fractions composition study of the pyrolysis oil obtained from sewage sludge treatment plant 总被引:1,自引:0,他引:1
Silva RV Romeiro GA Veloso MC Figueiredo MK Pinto PA Ferreira AF Gonçalves ML Teixeira AM Damasceno RN 《Bioresource technology》2012,103(1):459-465
In this work the parameters of Low Temperature Conversion - LTC were applied in a centrifuged sludge from a sewage treatment plant located in Rio de Janeiro, Brazil. Before the conversion, the sludge was dried and analyzed by TGA to observe its behavior with increasing temperature. The chemical composition of the crude pyrolysis oil was analyzed by FTIR, 1H NMR and GC-MS. The results showed that the oil is a mixture of hydrocarbons, oxygenated and nitrogenated compounds. Using a catalytic treatment it was possible to fractionate the oil where the predominant constituents were hydrocarbons showing that the cracking was effective. An important result was the difference between the calorific value of dry sludge (10 MJ kg−1), the pyrolysis oil (36 MJ kg−1) and one of the fractions separated by catalytic cracking (40 MJ kg−1) when compared with commercial diesel (45 MJ kg−1). 相似文献
6.
Yukio Imada Joji Takahashi Kōichi Yamada Kinya Uchida Kō Aida 《Bioscience, biotechnology, and biochemistry》2013,77(5):487-494
As already reported, strain S1OB1 was found to accumulate l-glutamic acid in a thiamine-deficient medium at the sole expense of hydrocarbon. In order to elucidate the biosynthetic pathway of l-glutamic acid, first of all, the incorporation of molecular oxygen into l-glutamic acid was examined. l-Glutamic acid accumulated under 18O-enriched atmosphere was separated, purified, identified and found to have been enriched with 18O. This results indicate the occurrence of oxygenase reaction involving addition of molecular oxygen. From a postulated biosynthetic pathway of l-glutamic acid, theoretical 18O content was calculated and compared with experimental one. 18O content of cells grown on n-alkane or glucose was also examined. 相似文献
7.
Yukio Imada E. C. Pantskhava Kōichi Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(2):245-254
Corynebacterium hydrocarboclastus S10BI or S489BI can accumulate a good deal of Lglutamate in a thiamine-deficient medium at the expence of hydrocarbon, but can not form L-glutamate in a thiamine-sufficient medium in spite of rapid cell growth, as already reported. In order to establish the optimal culture condition for L-glutamate formation, the influence of the following factors was first studied: hydrocarbon concentration, pH control, nitrogen sources, temperature, aeration and supplement of metal ions or amino acids. Then L-glutamate production from a variety of hydrocarbons or petroleum fractions was examined. Sodium oleate was found to stimulate growth remarkably instead of thiamine. Ferrous ion was found to be obligatory for L-glutamate formation and was suggested to have taken part in the earliest step of n-alkane oxidation. 相似文献
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As already reported, Corynebacterium hydrocarboclastus S10B1 was able to accumulate a good deal of l-glutamate in a thiamine-deficient medium at the sole expense of n-alkanes, but unable to form l-glutamate in a thiamine-sufficient medium though an abundant cell growth was observed.α-Ketoglutaric acid and dl-alanine were found to be produced in the same thiamine-deficient medium in which l-glutamate was accumulated. Both products formed from n-tetradecane by this organism were isolated from culture broth, purified and identified. The optimum concentration of thiamine in the culture medium was 3 to 5 µg per liter for their production. The maximum yields of α-ketoglutaric acid and dl-alanine reached 16 g and 1.5 g per liter in the calcium carbonate-added medium, respectively. However, the addition of more than 30 μg per liter of thiamine extremely repressed their accumulation. 相似文献
9.
The accumulation of vitamin B2 by Pichia guilliermondii Wickerham grown on hydrocarbon was investigated. Addition of the following materials stimulated vitamin B2 production: metal ions such as ferrous, cobalt, manganese, and calcium ions; organic nutrients such as yeast extract and casamino acid; amino acids such as proline and arginine; vitamins such as B1, nicotinic acid, inositol, and p-aminobenzoic acid. Optimal aeration rate for vitamin B2 production was obtained in a 500-ml shaking flask containing 75 ml of the medium. 相似文献
10.
Enzymatic deacylation of the lipopolysaccharide isolated from a Salmonella Rd mutant by a cell-free preparation from Acanthamoeba castellanii has been studied. The degradation was found to be dependent on the presence of a surface-active component (Triton X-100) in the reaction mixture. The lipid A part of the lipopolysaccharide was the primary target of the enzymes, which cleaved with high efficiency the ester-bound long-chain nonhydroxylated and 3-hydroxylated acyl residues, i.e. lauric, myristic, palmitic and 3-hydroxymyristic acid. The cell-free preparation also exhibited amidase activity cleaving about 50% of the amide-bound 3-hydroxymyristic acid residues. In addition the extract proved to possess phosphatase activity liberating ester-bound and glycosidically bound phosphate groups of lipid A. On the other hand, the glucosaminyl-beta 1,6-glucosamine disaccharide was not degraded and remained bound to the oligosaccharide part (heptose/3-deoxyoctulosonic acid) of the lipopolysaccharide. 相似文献
11.
J Grabarek G R Her V N Reinhold J Hawiger 《The Journal of biological chemistry》1990,265(14):8117-8121
We previously reported that human blood platelets are directly stimulated by endotoxic Lipid A via the protein kinase C pathway (Grabarek, J., Timmons, S., and Hawiger, J. (1988) J. Clin. Invest. 82, 964-971). To study the relationship between the molecular structure of Lipid A and its ability to activate human platelets, we used Lipid A homologs derived from Salmonella minnesota Re595 lipopolysaccharide. Preparations of Lipid A are heterogeneous in regard to the degree of substitution of fatty acids which result in multiple homologs. These were separated by thin-layer chromatography and characterized by fast atom bombardment spectroscopy and related techniques (Johnson R. S., Her, G.-R., Grabarek, J., Hawiger, J., and Reinhold, V. N. (1990) J. Biol. Chem. 265, 8108-8116). The homologs of monophosphoryl Lipid A (MLA) present in fractions TLC-8 (heptaacyl MLA ion, m/z 1953), TLC-7 (three hexaacyl species with predominant MLA ion m/z 1715), and TLC-6 (four pentaacyl homologs with predominant MLA ion, m/z 1505) induced secretion of [14C]serotonin and aggregation of platelets. Lipid A homologs in fractions TLC-5 (three tetraacyl MLA ions, m/z 1323, 1307, and 1279), TLC-4 (one major triacyl MLA ion, m/z 1097), TLC-3 (tetraacyl MLA ion, m/z 1278), TLC-2 (a diphosphoryl hexaacyl Lipid A ion, m/z 1795, and several ions of low abundance), and TLC-1 (two ions, m/z 1097 and 666) were not active in regard to human platelet aggregation and [14C]serotonin secretion. The most active homolog was heptaacyl MLA ion, m/z 1953, present in TLC-8, while homologs present in TLC-7 and TLC-6 were 5 and 10 times less active, respectively. Rapid phosphorylation of a human platelet protein of Mr 40,000-47,000 (P47), a substrate for protein kinase C activation, preceded secretion of serotonin when platelets were triggered by the most active heptaacyl MLA ion, m/z 1953. These events were time-dependent, with half-maximal response of phosphorylation of P47 at 30 s and [14C]serotonin secretion at 45 s. A marked difference in the degree of phosphorylation of P47 was observed with heptaacyl MLA homolog present in TLC-8 inducing complete phosphorylation (97%), whereas less acylated Lipid A homologs present in TLC-1 caused marginal phosphorylation (20%). These results indicate that the degree of acylation of monophosphoryl Lipid A determines its functional properties toward human platelets in regard to secretion of [14C]serotonin, aggregation, and activation of protein kinase C.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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In studies of the microflora associated with fuel storage tanks, a Fusarium species was isolated from No. 1 diesel fuel. The culture was identified as F. moniliforme Sheldon. Attempts were made to cultivate this organism with seven hydrocarbons of 99+ mole per cent purity as the sole carbon source; growth of the fungal culture was supported only by n-decane and n-dodecane. A spore viability study of F. moniliforme in filter-sterilized diesel fuel with no free water showed that viability was retained for 9 months in this environment. 相似文献
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Some typical and more frequent freshwater invertebrates of running waters were studied to examine the influence of styrene, xylene and benzene on their mortality. Snails Amphimelania holandri FÉR. and Lymnaea stagnalis L. and crustacenas Asellus aquaticus L. and Gammarus fossarum KOCH. , were used in the semi-static test. Compounds were added in volume concentrations of 0.005 to 0.4% v/v. For all concentrations LC50 was calculated by probit method, which demonstrated that mortality depends much more on increased concentrations (depending on the initial concentration) than on the length of exposure. Styrene was the most toxic, followed by xylene and then benzene. The species G. fossarum showed marked sensitivity, followed by A. aquaticus, and the species A. holandri and L. stagnalis showed less sensitivity. 相似文献
16.
Takashi Iguchi Isao Takeda Saburo Seno 《Bioscience, biotechnology, and biochemistry》2013,77(6):589-590
Large quantities of l-glutamic acid from liquid paraffins by microorganisms were produced with an addition of penicillin to the growing culture, and the action of penicillin to the glutamate production was studied. One of main effects of penicillin seems to exist in the cellular permeability of l-glutamic acid. 相似文献
17.
Kei Arima Shigeo Ogino Keiji Yano Gakuzo Tamura 《Bioscience, biotechnology, and biochemistry》2013,77(11):1004-1015
The production of microbial cell substances from hydrocarbons has been attracting attention of people for many years. Production of bacterial cell from hydrocarbons is disadvantageous because of the difficulty in separating cell from the broth.We have tested hydrocarbon-utilizing yeasts isolated from garden soil for cell production. The effect of medium composition on yeast growth and the utilization of individual hydrocarbon by yeast, strain Y-3, were investigated.As a nitrogen source, urea was more effective than ammonium nitrate. When a very smal! amount of corn steep liquor was added, yeast growth was very improved. Aliphatic series of hydrocarbon lower than C9 were not or very slightly assimilated by this yeast.Generally speaking, series of even-number hydrocarbons were more effective than those of odd-number hydrocarbons.We found that the yeast Y-3 strain reported in the previous paper1) has a diterminal oxidation system of hydrocarbon.This yeast capable of growing in mineral-salts solution with hydrocarbons as sole source of carbon produced a series of dioic acid from n-undecane. These acids are 1,11-undecane dioic acid, 1,9-nonane dioic acid (azelaic acid), 1,7-heptane dioic acid (pimelic acid) and 1,5-pentane dioic acid (glutaric acid). 1,10-Decane dioic acid (sebacic acid) was also isolated from n-decane cultures.Azelaic acid was partially transformed into pimelic acid and glutaric acid by treating it with resting cells of this yeast.1,11-Undecane dioic was also transformed into azelaic acid pimelic acid, and glutaric acid by the same treatment as described above. 相似文献
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Immunological state of adult germfree miniature minnesota pigs 总被引:2,自引:0,他引:2
Fundamental hematological and immunological data were obtained on sexually mature germfree miniature pigs fed, after the milk
diet period, with cereal-type diet sterilized by γ-radiation, and were compared with data of control conventional animals.
Germfree adult pigs had a lower count of peripheral blood leukocytes with a lower percentage of neutrophil granulocytes and
without any younger forms, a lower total serum protein level with a negligible amount of γ and α2 globulin fractions and a higher serum albumin and β globulin level. In the mesenteric lymph nodes and in spleen, surface
IgA-bearing cells predominated over surface IgG-bearing cells. Also a large amount of IgA-containing cells was found in the
intestinal lamina propria, where the IgG cells were present in a negligible amount. IgM cells were the most frequent surface
isotype in peripheral blood. The count of blood T lymphocytes was more than doubled. 相似文献