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101.
Pierce CY Barr JR Cody RB Massung RF Woolfitt AR Moura H Thompson HA Fernandez FM 《Chemical communications (Cambridge, England)》2007,(8):807-809
Direct analysis in real time (DART) is implemented on a time-of-flight (TOF) mass spectrometer, and used for the generation of fatty acid methyl esters (FAMEs) ions from whole bacterial cells. 相似文献
102.
103.
James J. Harrison Anatoli Onopchenko Michael T. Cheng Carrie Y. Chan 《Journal of polymer science. Part A, Polymer chemistry》2000,38(1):152-160
The Na2CO3‐promoted polymerization of 1,3‐dioxolan‐2‐one (I) to afford poly(ethylene glycol) III was reinvestigated. The reaction appeared to involve a nucleophilic attack against the carbonyl and methylene groups of I to afford poly(carbonate) II with poly(ethylene glycol) linkages and ethylene oxide IV as a side product (10–22%). As the reaction progressed, poly(carbonate) II decreased and poly(ethylene glycol) III increased. Under some conditions, poly(ethylene glycol)s V and VI with vinyl ether terminal groups were formed unexpectedly. The formation of unsaturated products during the polymerization of I/EO (ethylene oxide) has not been reported in the literature. We believe that vinyl ethers were formed from the degradation of poly(carbonate)s and were accompanied by a reduction in molecular weight. The structures of vinyl ethers V and VI were confirmed by hydrogenation of the double bond into the ethyl ether group in VII and VIII, respectively. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 152–160, 2000 相似文献
104.
Lih-Yuan Deng Jyh-Jen Horng Shiau Henry Horng-Shing Lu 《Journal of Computational and Applied Mathematics》2012
Utilizing some results in number theory, we propose an efficient method to speed up the computer search of large-order maximum-period Multiple Recursive Generators (MRGs). We conduct the computer search and identify many efficient and portable MRGs of order up to 25,013, which have the equi-distribution property in up to 25,013 dimensions and the period lengths up to 10233,361 approximately. In addition, a theoretical test is adopted to further evaluate and compare these generators. An extensive empirical study shows that these generators behave well when tested with the stringent Crush battery of the test package TestU01. 相似文献
105.
Brandon J. O'Neill David H. K. Jackson Anthony J. Crisci Carrie A. Farberow Fengyuan Shi Ana C. Alba‐Rubio Junling Lu Paul J. Dietrich Xiangkui Gu Christopher L. Marshall Peter C. Stair Jeffrey W. Elam Jeffrey T. Miller Fabio H. Ribeiro Paul M. Voyles Jeffrey Greeley Manos Mavrikakis Susannah L. Scott Thomas F. Kuech James A. Dumesic 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(51):14068-14068
106.
Dudzinski KM Brown SJ Lammers M Lucke K Mann DA Simard P Wall CC Rasmussen MH Magnúsdóttir EE Tougaard J Eriksen N 《The Journal of the Acoustical Society of America》2011,129(1):436-448
Deployment of any type of measuring device into the ocean, whether to shallow or deeper depths, is accompanied by the hope that this equipment and associated data will be recovered. The ocean is harsh on gear. Salt water corrodes. Currents, tides, surge, storms, and winds collaborate to increase the severity of the conditions that monitoring devices will endure. All ocean-related research has encountered the situations described in this paper. In collating the details of various deployment and recovery scenarios related to stationary passive acoustic monitoring use in the ocean, it is the intent of this paper to share trouble-shooting successes and failures to guide future work with this gear to monitor marine mammal, fish, and ambient (biologic and anthropogenic) sounds in the ocean-in both coastal and open waters. 相似文献
107.
We report on the first experimental demonstration of low-light-level cross-phase modulation (XPM) with double slow light pulses based on the double electromagnetically induced transparency (EIT) in cold cesium atoms. The double EIT is implemented with two control fields and two weak fields that drive populations prepared in the two doubly spin-polarized states. Group velocity matching can be obtained by tuning the intensity of either of the control fields. The XPM is based on the asymmetric M-type five-level system formed by the two sets of EIT. Enhancement in the XPM by group velocity matching is observed. Our work advances studies of low-light-level nonlinear optics based on double slow light pulses. 相似文献
108.
Cedervall PE Dey M Li X Sarangi R Hedman B Ragsdale SW Wilmot CM 《Journal of the American Chemical Society》2011,133(15):5626-5628
We present the 1.2 ? resolution X-ray crystal structure of a Ni-methyl species that is a proposed catalytic intermediate in methyl-coenzyme M reductase (MCR), the enzyme that catalyzes the biological formation of methane. The methyl group is situated 2.1 ? proximal of the Ni atom of the MCR coenzyme F(430). A rearrangement of the substrate channel has been posited to bring together substrate species, but Ni(III)-methyl formation alone does not lead to any observable structural changes in the channel. 相似文献
109.
Y. Y. C. Yeung Lam Ko P. Cosquer P. Pellon J. Hamelin R. Carrie 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):523-526
Abstract Diels Alder reaction provides an easy and general access to functionalized Δ3 phosphabenzenes after aromatization with the possibilities of introducing the functional group either with the diene or the phosphaalkene. 相似文献
110.
Ping Liu Thomas J. Lanza Jr.James P. Jewell Carrie P. JonesWilliam K. Hagmann Linus S. Lin 《Tetrahedron letters》2003,44(49):8869-8871
A highly active catalyst system for the heteroarylation of acetone has been identified. The coupling between the in situ generated tributyltin enolate of acetone and a variety of heteroaromatic bromides, chlorides, and triflates in the presence of this catalyst system provided arylacetones in good yields. 相似文献