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Ong RA Weir AJ Abrams GS Amidei D Baden AR Barklow T Boyarski AM Boyer J Burchat PR Burke DL Butler F Dorfan JM Feldman GJ Gidal G Gladney L Gold MS Goldhaber G Golding L Haggerty J Hanson G Hayes K Herrup D Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Karlen D Klein SR Lankford AJ Larsen RR LeClaire BW Levi M Lockyer NS Lüth V Nelson ME Perl ML Petersen A Richter B Riles K Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH Wood DR Yelton JM 《Physical review letters》1988,60(25):2587-2590
13.
Klein SR Himel TM Abrams G Amidei D Baden AR Barklow T Boyarski AM Boyer J Burchat PR Burke DL Butler F Dorfan JM Feldman GJ Gidal G Gladney L Gold MS Goldhaber G Golding L Haggerty J Hanson G Hayes K Herrup D Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Karlen D Lankford AJ Larsen RR LeClaire BW Levi M Lockyer NS Lüth V Matteuzzi C Nelson ME Ong RA Perl ML Petersen A Richter B Riles K Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH de la Vaissiere C Wood DR Yelton JM 《Physical review letters》1987,58(7):644-647
14.
H. Jara K. Boyer U. Johann T. S. Luk I. A. McIntyre A. McPherson C. K. Rhodes 《Applied physics. B, Lasers and optics》1987,42(1):11-15
The results of transient loss measurements performed in a self-sustained discharge KrF* amplifier are reported. Analysis of these results gives a minimum value of 20 for the effective gain to loss ratiog
0/eff, indicating that efficient extraction of energy in subpicosecond KrF* amplifiers in the 1 J range should be achievable. 相似文献
15.
Gidal G Boyer J Butler F Cords D Abrams GS Amidei D Baden AR Barklow T Boyarski AM Burchat P Burke DL Dorfan JM Feldman GJ Gladney L Gold MS Goldhaber G Golding LJ Haggerty J Hanson G Hayes K Herrup D Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Karlen D Klein SR Lankford AJ Larsen RR LeClaire BW Levi ME Lockyer NS Lüth V Matteuzzi C Nelson ME Ong RA Perl ML Richter B Riles K Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH de la Vaissière C Wood DR Yelton JM Zaiser C 《Physical review letters》1987,59(18):2016-2019
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Crouch R Boyer RD Johnson R Krishnamurthy K 《Magnetic resonance in chemistry : MRC》2004,42(3):301-307
Compensation of refocusing inefficiency in a gHMBC experiment by replacing the rectangular pi pulse with a pair of adiabatic pulses with synchronized inversion sweep (CRISIS) significantly improves the performance of the gHMBC experiment. The CRISIS-gHMBC experiment retains the pure absorptive shapes in F1 and hence results in better lineshape and higher resolution than the current versions of magnitude mode gHMBC spectra. When used as a broadband experiment, CRISIS-gHMBC, owing to better refocusing efficiency of the adiabatic pulse pairs, gives improved performance across the 13C spectral width. Moreover, it is shown that CRISIS-gHMBC is a robust and improved alternative and when used along with the IMPRESS (Improved Resolution using Symmetrically Shifted pulses) technique further increases the sensitivity and resolution without additional experimental time. The IMPRESS-CRISIS combination is demonstrated for broadband gHMBC and band-selective gHMBC experiments. The ICbs-gHMBC [IMPRESS-CRISIS-band-selective gHMBC] experiment is an attractive and better alternative to individual band-selective gHMBC. 相似文献
18.
Irradiation at 2537 Å eliminates carbon dioxide from 3-phenyl- Δ2-oxadiazol-5-one in either methanol or dioxane. A migration of phenyl from carbon to nitrogen leads to phenylcarbodiimide ( 8 ) which tautomerizes into phenylcyanamide ( 10 ). Benzamidine ( 11 ) and the 0-methyl ether ( 12 ) of benzamidoxime apparently result from hydrogen abstraction and insertion reactions of an intermediate unrearranged azomethine nitrene ( 9 ). More extensive fragmentation produces benzonitrile ( 7 ), which is isolated, and presumably phenylcarbene ( 20 ) to account for benzyl methyl ether ( 15 ). Generation of the carbene is discussed. The formation of 3,5-diphenyltriazole ( 6 ), triphenyltriazine ( 16 ) and N-cyanobenzamidine ( 15 ) remains unexplained. 相似文献
19.
Grandjean C Boutonnier A Guerreiro C Fournier JM Mulard LA 《The Journal of organic chemistry》2005,70(18):7123-7132
[reaction: see text] The nature of a linker used for preparing glycoconjugate vaccines is of utmost importance as it may lead to immunogenic biomolecules. We report the conjugation of carbohydrate haptens to protein carriers leading to potential vaccines using the traceless Staudinger ligation. The ligation relies on the selective transfer of a phosphane substituent to an azide to form a native amide bond in the final product upon release of an oxidized phosphane byproduct. We designed new phosphino-functionalized cross-linkers suitable for protein carrier derivatization. We evaluated their utility in preparing conjugates using both synthetic and purified bacterial carbohydrates. The use of a borane-protected phosphane which is deprotected at the time of the ligation reaction led to the best results observed thus far in terms of stability toward oxidation and reactivity. 相似文献
20.
Iain L. Marr Petra Kluge Laura Main Vincent Margerin Cyrille Lescop 《Mikrochimica acta》1995,119(3-4):219-232
Three sets of samples have been investigated in some detail. One set is from a river polluted by mine workings, containing substantial levels of Fe, Mn,Cu, Zn and Ni with traces of many other metals. The second set consists of typical estuarine sediments contaminated from a wide range of industrial sources, and the third set consists of oily drilling cuttings from the sea bottom in the vicinity of a North Sea oil production platform.These samples have been subjected to treatment 1) with EDTA at two different pH's (extracts) 2) with HNO3/H2O2 3) with HNO3/HCl and 4) with HNO3/HCl/HF (digests). EDTA recoveries, compared toaqua regia digests, are often very reproducible, not dependent on pH, and usually significantly low. Nitric/peroxide andaqua regia digests often give very close results suggesting that these are meaningful values indicating the maximum levels of polluting metals in the sediments. However, the triple acid digest with HF does sometimes give higher values (and reasonable agreement for CRM's such as MESS-1) but with poorer reproducibility. 相似文献