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11.
Towards an Environmentally Acceptable Heterogeneous Catalytic Method of Producing Adipic Acid by the Oxidation of Hydrocarbons in Air 总被引:1,自引:0,他引:1
Raja Robert Lee Sang-Ok Sanchez-Sanchez Manuel Sankar Gopinathan Harris Kenneth D.M. Johnson Brian F.G. Thomas John Meurig 《Topics in Catalysis》2002,20(1-4):85-88
A survey is given of the catalytic methods potentially available for the production of adipic acid by the oxidation of readily available hydrocarbon precursors under environmentally benign conditions. Encouraging results are reported using H2O2 as oxidant and microporous FeAlPO-5 as catalyst at moderate temperatures. 相似文献
12.
A differentiation between free carboxyl and various lactone groups in different types of oxycelluloses was carried out based on the variation in their reaction rate with KI/KIO3 solution. For oxycelluloses prepared under acidic conditions, a large proportion of carboxyl groups are present in free form. Each oxycellulose was also studied after cation freeing as well as after blocking the free carboxyl groups by treatment with sodium chloride. Cation freeing was found to cause considerable lactonization of carboxyl groups; sodium chloride treatment blocked them only partially. 相似文献
13.
A series of novel copolymer superabsorbents based on monomer acrylamide (AM), potassium methacrylate (KMA), and 2‐hydroxyethyl methacrylate (HEMA) were prepared by copolymerization using ammonium persulfate (APS) as an initiator and N,N‐methylenebisacrylamide (MBA) as a crosslinking agent. The synthetic variables (the monomer concentration, crosslinker concentration, and initiator concentration) were also studied. The experimental results of superabsorbent polymers (SAPs) show a better absorbency in both water and NaCl solutions. The copolymers were characterized by IR spectroscopy. The water retention in the soil was enhanced using the above superabsorbents. The use of SAPs for the growth of groundnut plants was also investigated. SAPs can be considered for water‐managing materials for agriculture and horticulture purposes in desert and drought‐prone areas. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1795–1801, 2002 相似文献
14.
Creaser E.H.; Murali C.; Britt K.A. 《Protein engineering, design & selection : PEDS》1990,3(6):523-526
By protein engineering we have investigated changes to two aminoacid residues (Trp93 and Ser48) in the substrate pocket of yeastalcohol dehydrogenase 1. Upon changing Thr48 to serine we producedan enzyme which has markedly greater activity towards aliphaticalcohols with chain length up to 8, together with a generalincrease in catalytic activity (V/K). Changes at position 93were less pronounced, with the Phe enzyme being more activethan the parent towards the range of alcohols but with the alanineenzyme showing very little difference from the wild-type. Enzymeswith the double changes at 48 and 93 showed increased activitytowards alcohols with 38 carbons but the increases werenot additive over the single changes. The enzymes with changesat the two positions would metabolize both stereoisomers of2-octanol whereas the parent ADH would attack only one of them.None of the engineered enzymes would attack cyclohexanol oraromatic alcohols. The results are in general agreement withthe prediction that reducing the size of amino acids in thesubstrate pocket would enhance the ability to oxidize alcoholslarger than ethanol. 相似文献
15.
J. C. Moreland G. L. Wilkes C. G. Moreland S. S. Sankar E. O. Stejskal R. B. Turner 《应用聚合物科学杂志》1994,52(9):1175-1180
High-resolution solid-state 13C-NMR has been used to study the phase separation and molecular motion in two series of polyurethane foams. These two series differ by one possessing the additive of lithium chloride, LiCl. NMR relaxation times can map the motion throughout the polymer molecule and detect changes in that motion arising from either microseparation or phase mixing between the different segments. There are only slight changes in the soft segment T1p(13C) values as well as an increase in the hard segment T1p(1H) values with increase in the hard segment content for the foams studied. The T1p(1H) and T1p(13C) values do indicate that the phase separation of the hard and soft segments is similar for all foams. A decrease in the T1p(1H) and T1p(13C) values with increasing LiCl content indicates that the motion of the soft segments is restricted more by the hard segments. This is explained by more phase mixing in the foams containing the LiCl additive. © 1994 John Wiley & Sons, Inc. 相似文献
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We consider a structural approach to the consensus building problem in multi‐group multi‐layer (MGML) distributed sensor networks (DSNs) common in many natural and engineering applications. From among the possible network structures, we focus on bipartite graph structure as it represents a typical MGML structure and has a wide applicability in the real world. We establish exact conditions for consensus and derive a precise relationship between the consensus value and the degree distribution of nodes in a bipartite MGML DSN. We also demonstrate that for subclasses of connectivity patterns, convergence time and simple characteristics of network topology can be captured by explicit algebra. Direct inference of the convergence behavior of consensus strategies from MGML DSN structure is the main contribution of this paper. The insights gained from our analysis facilitate the design and development of large‐scale DSNs that meet specific performance criteria. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
19.
Software testing plays a pivotal role in entire software development lifecycle. It provides researchers with extensive opportunities to develop novel methods for the optimized and cost-effective test suite Although implementation of such a cost-effective test suite with regression testing is being under exploration still it contains lot of challenges and flaws while incorporating with any of the new regression testing algorithm due to irrelevant test cases in the test suite which are not required. These kinds of irrelevant test cases might create certain challenges such as code-coverage in the test suite, fault-tolerance, defects due to uncovered-statements and overall-performance at the time of execution. With this objective, the proposed a new Modified Particle Swarm optimization used for multi-objective test suite optimization. The experiment results involving six subject programs show that MOMPSO method can outer perform with respect to both reduction rate (90.78% to 100%) and failure detection rate (44.56% to 55.01%). Results proved MOMPSO outperformed the other stated algorithms. 相似文献
20.
Jun Pan Li Na Quan Yongbiao Zhao Wei Peng Banavoth Murali Smritakshi P. Sarmah Mingjian Yuan Lutfan Sinatra Noktan M. Alyami Jiakai Liu Emre Yassitepe Zhenyu Yang Oleksandr Voznyy Riccardo Comin Mohamed N. Hedhili Omar F. Mohammed Zheng Hong Lu Dong Ha Kim Edward H. Sargent Osman M. Bakr 《Advanced materials (Deerfield Beach, Fla.)》2016,28(39):8718-8725