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81.
Prebyl BS Johnson JD Tuinman AA Zhou S Cook KD 《Journal of the American Society for Mass Spectrometry》2002,13(8):921-927
Collision-induced dissociation in the source of an electrospray (ES) mass spectrometer was employed to characterize putative samples of the ionic terpolymer poly(styrene sulfonate-co-acrylic acid-co-2-acrylamido-2-methyl-1-propanesulfonic acid). Qualitative and semi-quantitative information about the monomer content was quickly obtainable from ES spectra, and indicated that some samples contained little or none of one or two expected comonomers. For two representative samples, confirmatory nuclear magnetic resonance (NMR) data were acquired. The NMR experiments required sample clean-up (to remove additives) and long acquisition times (up to 720 min) for 13C NMR. Cleanup also improved the ES results, providing better agreement with the NMR data. However, qualitative and semi-quantitative information was obtainable by ES (but not by NMR) without the cleanup step. Full quantitation of monomer ratios would require suitable standards, but even without such standards the ES measurements provide a rapid (<1 min) means for differentiating these samples (e.g., for process or quality control). 相似文献
82.
Kelsey D Cook Associate Editor 《Journal of the American Society for Mass Spectrometry》2002,13(12):367-1359
Editorial
ASMS members John Fenn and Koichi Tanaka share Nobel: The world learns our “secret” 相似文献83.
84.
S. Barlag H. Becker T. Böhringer M. Bosman V. Castillo V. Chabaud D. Buchholz C. Damerell C. Daum H. Dietl H. Fawcett S. Gill A. Gillman R. Gilmore T. Gooch L. Görlich P. Gras Z. Hajduk E. Higon B. D. Hyams D. P. Kelsey J. Kemmer R. Klanner U. Kötz S. Kwan B. Lücking G. Lütjens G. Lutz J. Malos W. Männer E. Neugebauer H. Palka M. Pepe J. Richardson G. De Rijk K. Rybicki H. J. Seebrunner U. Stierlin H. G. Tiecke M. Turala G. Waltermann S. Watts P. Weilhammer F. Wickens L. W. Wiggers M. Witek A. Wylie T. Zeludziewicz ACCMOR Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,39(4):451-460
The NA 32 experiment at the CERN SPS has collected 38 million hadronic interactions with incident 200 GeV/c π?,K ? andp beam. Using a segmented silicon active target and a telescope of high resolution silicon microstrip counters we have selected fully reconstructedD 0→K ?π+,D 0→K ?π+π+π?,D +→K ?π+π+,D s + →K ? K +π+π+ and charge conjugate decays. The integrated cross-sections forD o,D + D *+ andD s + meson production and the dependence of the cross-section on longitudinal and transverse momentum of theD are presented. 相似文献
85.
Gavin H. West Bruce E. Lippy Michael R. Cooper Daniel Marsick Leonard G. Burrelli Kelsey N. Griffin Alan M. Segrave 《Journal of nanoparticle research》2016,18(2):49
The global construction sector is experiencing major improvements to building materials used in large quantities through commercial applications of nanotechnology. Nano-enabled construction products hold great promise for energy efficiency and resource conservation, but risk assessments lag as new products emerge. This paper presents results from an inventory, survey, and exposure assessment conducted by the authors and explores these findings in the broader context of evolving research trends and responsible development of nanotechnology. An inventory of 458 reportedly nano-enabled construction products provided insight into product availability, potential exposures, and deficiencies in risk communication that are barriers to adoption of proactive safety measures. Seasoned construction trainers surveyed were largely unaware of the availability of nano-enabled construction products. Exposure assessment demonstrated the effectiveness of ventilation to reduce exposures during mechanical abrasion of photocatalytic tiles containing titanium dioxide (TiO2). Dissociated particles of TiO2 just above the nanoscale (138 nm) were detected in the debris collected during cutting of the tiles, but measurements were below recommended exposure limits for TiO2. Exposure assessments remain scarce, and toxicological understanding primarily pertains to unincorporated nanomaterials; less is known about the occupational risks of nano-enabled construction products across their life cycle. Further research is needed to characterize and quantify exposure to debris released from nanocomposite materials for realistic risk assessment, and to ascertain how nanocomposite matrices, fillers, and degradation forces interact to affect release dynamics. Improving risk communication strategies and implementing safe work practices will cultivate responsible development of nanotechnology in construction, as will multidisciplinary research efforts. 相似文献
86.
Bai JZ Bardon O Becker-Szendy RA Burnett TH Campbell JS Chen SJ Chen SM Chen YQ Cheng ZD Coller JA Cowan RF Cui HC Cui XZ Ding HL Du ZZ Dunwoodie W Fang C Fero MJ Gao ML Gao SQ Gao WX Gao YN Gu JH Gu SD Gu WX Guo YN Guo YY Han Y Hatanaka M He J Hitlin DG Hu GY Hu T Huang DQ Huang YZ Izen JM Jia QP Jiang CH Jiang ZJ Johnson AS Jones LA Kelsey MH Lai YF Lang PF Lankford A Li F Li J Li PQ Li QM Li RB Li W Li WD Li WG Li YS Lin SZ Liu HM Liu Q Liu RG Liu Y Lowery B Lu JG Ma DH Ma EC Ma JM 《Physical review letters》1992,69(21):3021-3024
87.
88.
Bennett KH Cook KD Seebach GL 《Journal of the American Society for Mass Spectrometry》2000,11(12):579-1085
The feasibility of simultaneous analysis of mixtures containing two to four butene isomers and up to six total components using process mass spectrometry is assessed. As for typical (nonisomeric) applications of process mass spectrometry, simultaneous analysis is based on the assumption that the electron ionization mass spectra of mixtures are linear combinations of the spectra of the individual constituents. Limits of detection for binary isomer mixtures are on the order of 0.1% to 10%, limited by the ability to distinguish small differences between similar spectra. As spectral and mixture complexity increase, both accuracy and precision decrease. Not surprisingly the similarity of the spectra of stereoisomers cis- and trans-2-butene is greater than that of the other (nonstereoisomeric) isomer pairs, and mixtures containing both cis- and trans-2-butene are the most difficult to quantitate. However, even for mixtures of all four butenes, accuracy (root-mean-square ERROR = 2.43%), precision (average coefficient of VARIATION = 6.72%), and linearity (correlation coefficient of a plot of measured versus actual concentration r2 = 0.985 ± 0.002) are reasonably good. 相似文献
89.
Bai JZ Bardon O Blum I Breakstone A Burnett T Chen GP Chen HF Chen J Chen SM Chen Y Chen YB Chen YQ Cheng BS Cowan RF Cui XZ Ding HL Du ZZ Dunwoodie W Fan XL Fang J Fero M Gao CS Gao ML Gao SQ Gratton P Gu JH Gu SD Gu WX Gu YF Guo YN Han SW Han Y Harris FA Hatanaka M He J He M Hitlin DG Hu GY Hu T Hu XQ Huang DQ Huang YZ Izen JM Jia QP Jiang CH Jin S Jin Y Jones L Kang SH Ke ZJ Kelsey MH Kim BK Kong D Lai YF Lan HB Lang PF Lankford A Li F Li J Li PQ Li Q Li RB Li W Li WD 《Physical review D: Particles and fields》1996,54(1):1221-1224
90.
Williams DE Keyzers RA Warabi K Desjardine K Riffell JL Roberge M Andersen RJ 《The Journal of organic chemistry》2007,72(25):9842-9845
Five new macrolides, spirastrellolides C (3) to G (7), have been isolated from extracts of the marine sponge Spirastrella coccinea collected in Dominica. Their structures have been elucidated by a combination of spectroscopic analysis and chemical transformations. 相似文献