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1.
de Santana Felipe Silva Gracioso Louise Hase Karolski Bruno dos Passos Galluzzi Baltazar Marcela Mendes Maria Anita do Nascimento Claudio Augusto Oller Perpetuo Elen Aquino 《Applied biochemistry and biotechnology》2019,189(1):103-115
Applied Biochemistry and Biotechnology - The human exposure to bisphenol A (BPA) occurs frequently. Once, this compound was one of the highest volume chemicals produced worldwide and used as a... 相似文献
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A. Louise Perkins 《BIT Numerical Mathematics》1992,32(4):598-608
The choice of data structures influences the parallelization, efficiency and the manageability of a mesh refinement program. We introduce a mixed directed-undirected graph that combines both communication and scheduling needs. An inverted index is maintained for the directed graph to improve code performance and readability.This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48. 相似文献
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Abhimanyu O. Patil Stephen Zushma Robert T. Stibrany Steven P. Rucker Louise M. Wheeler 《Journal of polymer science. Part A, Polymer chemistry》2003,41(13):2095-2106
Novel nickel(II) bisbenzimidazole complexes were prepared via a three‐step synthetic procedure consisting of aniline/diacid condensation, ligand N‐alkylation, and metal complexation. The complexes were characterized by X‐ray crystallography and found to possess a pseudotetrahedral geometry. Upon activation with methylaluminoxane, these nickel bisbenzimidazoles did not polymerize simple olefins (e.g., ethylene, propylene, and 1‐butene) but were found to carry out the rapid and efficient polymerization of norbornene. The polynorbornene products were characterized by gel permeation chromatography/light scattering, 13C NMR, and IR, and their Mark–Houwink and dn/dc parameters were determined. The molecular weights of the polynorbornenes were very high (weight‐average molecular weight = 587,000–797,000 g/mol). 13C NMR suggested that the polymerization occurred via vinyl addition (i.e., a 2,3‐linked polymer); no ring‐opened product was observed. Thermogravimetric analysis indicated that the polynorbornenes were stable up to 400 °C under nitrogen. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2095–2106, 2003 相似文献
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A simplex procedure is shown to be an efficient approach for solving separation problems. The best solvent ratio for the separation of phosphatidylcholine and sphingomyelin has been found by means of a two-dimensional simplex capable of expansion and contraction. A successful high-pressure liquid chromatography separation of lysophosphatidylcholine, phoaphatidylethanolamine, phosphatidylinositol, phosphatidylserine, phosphatidylcholine, sphingomyelin and phosphatidic acid was achieved with a 180-cm column packed with Corasil II and a solvent mixture of chloroform—methanol—ammonia (50.0:35.9:7.0, v/v/v). 相似文献
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Pradeep Mathur Bala Manimaran Md. Munkir Hossain Arnold L. Rheingold Louise M. Liable-Sands Glenn P.A. Yap 《Journal of organometallic chemistry》1997,540(1-2):165-168
The tris-methylene bridged compound (NO)4Fe2Se(μ-CH2)3 has been isolated. It has been characterised by IR and 1H, 13C, and 77Se NMR spectroscopy. Its structure has been determined by single-crystal X-ray diffraction methods. The structure consists of a heavy atom triangle consisting of one Se and two Fe atoms. The Fe-Fe and the two Fe-Se edges are bridged by methylene groups. 相似文献
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Mineral and short-chain carboxylic acid vapours and NO(x) gases were reacted with cyclohexene oxide (1,2-epoxycyclohexane) to quantitatively produce specific, thermally stable cyclohexyl derivatives. Subsequent analysis of these derivatives by gas chromatography with mass spectroscopy and flame ionisation detection afforded a multi analyte method for the assay of these gaseous acidic atmospheric species. Derivatisation was found to be quantitative for the derivatives tested and the method highly sensitive (to 0.3 mg/m3 for a 30 l sample), accurate, precise and free from apparent interferences. The technique has been applied to "acid stack gases" and a number of other acid rich atmospheres and the results obtained show good agreement with the single analyte wet chemical determinations indicating that the approach has considerable potential as a routine analytical method for measuring such atmospheric pollutants. The high specificity of the reaction mechanism and its potential for the analysis of analyte mixtures is illustrated in the assay of nitric acid and its acid anhydride, dinitrogen pentoxide. 相似文献