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Sushanta K. Badamali Rafael Luque James H. ClarkSimon W. Breeden 《Catalysis communications》2011,12(11):993-995
The microwave-assisted oxidative degradation of a lignin model phenolic dimer [1-(4-hydroxy-3-methoxyphenoxy)-2-(2-methoxyphenoxy)-propane-1,3-diol, 1] catalysed by Co(salen)/SBA-15 is reported. The investigated model compound 1 was prepared through a multistep synthesis and characterized by 1H,13C NMR, and GC–MS studies. The catalyst was prepared by immobilizing [N,N′-bis(salicylidene)ethane-1,2-diaminato]Cobalt(II), Co(salen) complex onto the periodic mesopore channels of siliceous SBA-15. The activity of the Co(salen)/SBA-15 was investigated in the oxidation of 1 in the presence of hydrogen peroxide as oxidant, both under microwave irradiation and conventional heating. The phenolic dimer was selectively oxidized to 2-methoxy phenol with very high TON under microwave activation conditions. Comparatively, reactions run under conventional heating led to oligomerisation of the dimer and resulted in a mixture of products. 相似文献
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Microwave assisted oxidation of the lignin model monomer apocynol, 1-(4-hydroxy-3-methoxyphenoxy)-ethanol was carried out over mesoporous SBA-15 catalyst using H2O2 as oxidant to produce acetovanillone, vanillin and 2-methoxybenzoquinone. Reaction conditions were optimised in order to obtain acetovanillone selectively, which serves as a raw material for 3,4-dimethoxybenzoic acid, a building block for synthesis of the smooth muscle relaxant mebeverin. Under conventional heating reactions were sluggish and gave poor yields of a mixture of products. The use of increased amount of catalyst resulted in lowering of acetovanillone selectivity. The possibility of recycling the catalyst was also studied. 相似文献
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R Beerman A Bendell A Breeden AL Denker G Gallego VS Harvin MM Kontz JA Krueger-Jones MO Martin J Mass K Oza ME Perdue J Rogers S Sears A Williams-Welch 《Canadian Metallurgical Quarterly》1998,22(3):18-65
Change, challenge, and commitment motivate staff at the University of Miami/Jackson Memorial Medical Center in Miami, Florida, to prepare its health care system for the 21st century. Doctors, nurses, environmental workers, pharmacists, cashiers, nursing assistants, laboratory technologists, and many others are participating on a variety of teams to bring about the changes needed for our delivery system to be competitive. 相似文献
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JO Breeden 《Canadian Metallurgical Quarterly》1993,86(9):1040-1048
The Union's decision to treat medicines and medical supplies as contraband of war meant, for the Confederacy, the specter of medical shortages. The Confederate medical department significantly lessened the subsequent suffering through an energetic and resourceful program to supply its physicians' needs. Medicines and medical supplies were purchased abroad and smuggled through the Union blockade, obtained in an illicit trade with the North, captured from the enemy, and manufactured in the Confederacy. The search for home remedies, enthusiastically endorsed by Surgeon General Samuel P. Moore, was one of the most prominent features of the southern program. This paper surveys and analyzes medical shortages and Confederate medicine. 相似文献
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Objective: To explore how parents' physical disability status might impact the process of divorce-related child custody evaluations and custody decisions, the level of training received by psychologists regarding assessment of parents with physical disabilities, and whether psychologists recognize that testing persons with physical disabilities requires specialized knowledge. Study Design: Survey mailed in 4 waves. Participants: 206 child custody evaluators (31% response rate). Outcome Measures: A survey regarding custody evaluations, a custody questionnaire, evaluation practices, education and training regarding disability, demographics, and a question about the purpose of the study. Results: Almost 70% had performed ≥1 child custody evaluation involving a parent with a physical disability. Over 85% of participants reported no training with regard to such evaluations, and 49% reported no training regarding any disability issues. 65% stated they would use the same tests without modifications, regardless of disability status of the parent. Conclusions: Recommendations include mandated training on disability for child custody evaluators, graduate training on disability accommodations in assessment, specifying conditions when evaluating parents with disabilities, more information regarding accommodations in custody evaluations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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David C. Breeden Todd E. Young Robert M. Coates John A. Juvik 《Journal of chemical ecology》1996,22(3):513-539
Hexane extracts of leaves of 307 accessions from 73 host plant species ofHelicoverpa zea were analyzed by gas chromatography (GC) and used forH. zea oviposition and neonate larvae orientation bioassays. The gas chromatographic (GC) retention times of compounds statistically associated with behavioral activity were identified by correlation of GC peak area with oviposition and larval orientation preferences. Although taxonomically diverse in their origin, compounds for study were purified from extracts of species of the genusLycopersicon, due to their relative abundance. The structures of eight long-chain alkanes associated with oviposition preference were assigned by mass spectrometry, and the structures of five similarly associated organic acids and a terpenoid alkene were identified by1H and13C nuclear magnetic resonance spectroscopy. The structures of a number of other phytochemicals from the plant leaves were identified for comparative purposes, including a previously unknown terpene, 7-epizingiberene. Bioassays were performed on the isolated acids and on the alkane wax fractions of severalLycopersicon species, and significant differences were found in oviposition stimulation for both classes of compounds. Of the hundreds of compounds found in the extracts, none were observed to act as oviposition deterrents. The results of these bioassays may be useful in explaining the broad host range ofH. zea, as well as the process and evolution of host plant selection for oviposition. 相似文献