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1.
Xiao LiWei Xing Shuping Zhuo Jin ZhouFeng Li Shi-Zhang QiaoGao-Qing Lu 《Bioresource technology》2011,102(2):1118-1123
Series of nanoporous carbons are prepared from sunflower seed shell (SSS) by two different strategies and used as electrode material for electrochemical double-layer capacitor (EDLC). The surface area and pore-structure of the nanoporous carbons are characterized intensively using N2 adsorption technique. The results show that the pore-structure of the carbons is closely related to activation temperature and dosage of KOH. Electrochemical measurements show that the carbons made by impregnation-activation process have better capacitive behavior and higher capacitance retention ratio at high drain current than the carbons made by carbonization-activation process, which is due to that there are abundant macroscopic pores and less interior micropore surface in the texture of the former. More importantly, the capacitive performances of these carbons are much better than ordered mesoporous carbons and commercial wood-based active carbon, thus highlighting the success of preparing high performance electrode material for EDLC from SSS. 相似文献
2.
Ranganathan Santhanam 《Inorganica chimica acta》2008,361(2):473-478
A novel method of preparation of hexahydroaluminate complexes M3AlH6 (M = Li, Na or K) from the corresponding alkali metal hydride and tetrahydroaluminate has been explored, using dimethyl ether (Me2O) as a solvent at near-ambient temperatures. The results are compared with those obtained using a recently established mechanochemical approach. Characterization of the products by powder X-ray diffraction revealed M3AlH6 to be formed in high yield for M = Li and Na, but not for M = K. The attempted preparation of Li2NaAlH6 and Li2KAlH6 was unsuccessful. 相似文献
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D. G. Ahearn R. B. Simmons D. L. Price L. Ajello S. A. Crow S. K. Mishra D. L. Pierson 《Journal of industrial microbiology & biotechnology》1995,14(1):26-30
Summary Materials being used or considered for use in space flight were examined for their susceptibility to fungal colonization. The materials included soft goods (clothing) and insulation and fabrication products such as Velcro® attachments and elastic cord binders. Materials were exposed for at least 28 days in a highhumidity chamber colonized with over 50 species of fungi, including those species recommended for determining recalcitrance of materials to fungal biodegradation. At least nine of 25 products demonstrated extensive microscopic colonization by fungi, mostly byAcremonium obclavatum. Challenge procedures that rely on observations with the unaided eye, or 40×magnification of growth by a restricted number of fungal species with a cellulosic substrate as a positive control, are insufficient for determining the resistance of synthetic substrates to fungal colonization. 相似文献
5.
实验中观察到,用MUG培养基对植物药中的大肠杆菌定量时多发生荧光猝灭现象,影响检测结果。本文对此现象产生的原因与克服方法进行了系统的考察,发现以一种简便的转接方法可排除植物药介质对菌检的干扰。该方法由两组检验系列构成,当怀疑正常稀释系列(第一系列)40h培养液的荧光结果可能因猝灭现象呈假阴性时,立即分别将该系列的1—3号管培养液以0.5ml的接种量转接入新鲜的MUG培养基(第二系列),重新培养24h,荧光猝灭现象即可克服。综合两系列的荧光、产气和吲哚三项生化特征得出检品中大肠杆菌含量。实际应用表明,此法能显著提高使用该培养基时菌检结果的可靠性。 相似文献
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Mohd Imran Shahzad Ahmed Ahmad Zuhairi Abdullah Jabir Hakami Anis Ahmad Chaudhary Hassan Ahmad Rudayni Salah-Ud-Din Khan Afzal Khan Nosiba Suliman Basher 《Luminescence》2023,38(7):1064-1086
The penicillin derivative amoxicillin (AMX) plays an important role in treating various types of infections caused by bacteria. However, excessive use of AMX may have negative health effects. Therefore, it is of utmost importance to detect and quantify the AMX in pharmaceutical drugs, biological fluids, and environmental samples with high sensitivity. Therefore, this review article provides valuable and up-to-date information on nanostructured material-based optical and electrochemical sensors to detect AMX in various biological and chemical samples. The role of using different nanostructured materials on the performance of important optical sensors such as colorimetric sensors, fluorescence sensors, surface-enhanced Raman scattering sensors, chemiluminescence/electroluminescence sensors, optical immunosensors, optical fibre-based sensors, and several important electrochemical sensors based on different electrode types have been discussed. Moreover, nanocomposites, polymer, and MXenes-based electrochemical sensors have also been discussed, in which such materials are being used to further enhance the sensitivity of these sensors. Furthermore, nanocomposite-based photo-electrochemical sensors and the market availability of biosensors including AMX have also been discussed briefly. Finally, the conclusion, challenges, and future perspectives of the above-mentioned sensing techniques for AMX detection are presented. 相似文献
8.
The significance of polyoxometalates in the field of molecular magnetism is discussed. We show that this kind of inorganic complexes provides remarkable examples for the study of the exchange interactions in clusters. On the other hand, we examine the possibility of using these metal oxide anions as magnetic components of molecular materials containing organic tetrathiafulvalenes as electron donor molecules. 相似文献
9.
Acyl Group Migrations in 2-Monoolein 总被引:6,自引:0,他引:6
Anna Millqvist Fureby Carmen Virto Patrick Adlercreutz Bo Mattiasson 《Biocatalysis and Biotransformation》1996,14(2):89-111
Acyl migration in 2-monoolein dissolved in solvents under conditions common in lipid modification reactions has been studied. The effects on acyl migration of solvent, incubation temperature, water activity, polar additives and solid additives have been investigated. Extensive acyl migration occured in aliphatic hydrocarbons and water-miscible alcohols under dry conditions. The acyl migration rate could be decreased in several nonpolar solvents by adding a small amount of water or an alcohol. Increasing water activity had no effect in isooctane, but decreased the acyl migration rate dramatically in methyl tert-butyl ether and methyl isobutyl ketone. Several commonly used enzyme supports catalysed acyl migration, showing that supports with surface charges could catalyse acyl migration. 相似文献
10.
Samuel H. Barondes Eric C. Beyer Wayne R. Springer Douglas N. Cooper 《Journal of cellular biochemistry》1981,16(3):233-242
Endogenous lectins in both cellular slime molds and chicken tissues have been localized primarily intracellularly, in contrast with the predominantly extracellular localization of the glycoproteins, glycolipids, and glycosaminoglycans with which they might interact. Here we present evidence that lectins in both of these organisms may be externalized and become associated with the cell surface and/or extracellular materials. In chicken intestine, chicken-lactose-lectin-II is shown to be localized in the secretory granules of the goblet cells, along with mucin, and to be secreted onto the intestinal surface. In embryonic muscle, chicken-lactose-lectin-I is shown to be externalized with differentiation, ultimately becoming localized on the surface of myotubes and in the extracellular spaces. In a cellular slime mold, Dictyostelium purpureum, externalization of lectin is elicited by either polyvalent glycoproteins that bind the small amount of endogenous cell surface lectin, or by slime mold or plant lectins that bind unoccupied complementary cell surface oligosaccharides. These results suggest that externalization of endogenous lectin may be a response to specific external signals. We conclude that lectins are frequently held in intracellular reserves awaiting release for specific external functions. 相似文献