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排序方式: 共有538条查询结果,搜索用时 46 毫秒
31.
Christian DC Felix J Gottschalk EE Gutierrez G Hartouni EP Knapp BC Kreisler MN Moreno G Reyes MA Sosa M Wang MH Wehmann A 《Physical review letters》2005,95(15):152001
We report the results of a high-statistics, sensitive search for narrow baryon resonances decaying to Xi-pi-, Xi-pi+, Xi+pi-, and Xi+pi+. The only resonances observed are the well known Xi0(1530) and Xi0(1530). No evidence is found for the states near 1862 MeV, previously reported by NA49 [Phys. Rev. Lett. 92, 042003 (2003)]. At the 95% confidence level, we find the upper limit for the production of a Gaussian enhancement with sigma=7.6 MeV in the Xi-pi- effective mass spectrum to be 0.3% of the number of observed Xi0(1530)-->Xi-pi+. We find similarly restrictive upper limits for an enhancement at 1862 MeV in the Xi-pi+, Xi+pi-, and Xi+pi+ mass spectra. 相似文献
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33.
Wang MH Berisso MC Christian DC Félix J Gara A Gottschalk E Gutiérrez G Hartouni EP Knapp BC Kreisler MN Lee S Markianos K Moreno G Reyes MA Sosa M Wehmann A Wesson D 《Physical review letters》2001,87(8):082002
We report the first observation of diffractively produced open charm in 800-GeV/c pp collisions of the type pp-->pD*X. We measure cross sections of sigma(diff)(D*+) = (0.185+/-0.044+/-0.054) (mu)b and sigma(diff)(D(*-)) = (0.174+/-0.034+/-0.029) (mu)b. Our measurements are based on 4.3x10(9) events recorded by FNAL E690 in the fixed-target run of 1991. We compare our results with previous fixed-target charm experiments. 相似文献
34.
Abu-Zayyad T Belov K Bird DJ Boyer J Cao Z Catanese M Chen GF Clay RW Covault CE Cronin JW Dai HY Dawson BR Elbert JW Fick BE Fortson LF Fowler JW Gibbs KG Glasmacher MA Green KD Ho Y Huang A Jui CC Kidd MJ Kieda DB Knapp BC Ko S 《Physical review letters》2000,84(19):4276-4279
The average mass composition of cosmic rays with primary energies between 10(17) and 10(18) eV has been studied using a hybrid detector consisting of the High Resolution Fly's Eye (HiRes) prototype and the MIA muon array. Measurements have been made of the change in the depth of shower maximum and the muon density as a function of energy. The results show that the composition is changing from a heavy to lighter mix as the energy increases. 相似文献
35.
Dr. Carlo Fasting Prof. Christoph A. Schalley Dr. Marcus Weber Prof. Oliver Seitz Prof. Stefan Hecht Prof. Beate Koksch Dr. Jens Dernedde Prof. Christina Graf Prof. Ernst‐Walter Knapp Prof. Rainer Haag 《Angewandte Chemie (International ed. in English)》2012,51(42):10472-10498
Multivalent interactions can be applied universally for a targeted strengthening of an interaction between different interfaces or molecules. The binding partners form cooperative, multiple receptor–ligand interactions that are based on individually weak, noncovalent bonds and are thus generally reversible. Hence, multi‐ and polyvalent interactions play a decisive role in biological systems for recognition, adhesion, and signal processes. The scientific and practical realization of this principle will be demonstrated by the development of simple artificial and theoretical models, from natural systems to functional, application‐oriented systems. In a systematic review of scaffold architectures, the underlying effects and control options will be demonstrated, and suggestions will be given for designing effective multivalent binding systems, as well as for polyvalent therapeutics. 相似文献
36.
Miniaturized multichannel electrospray ionization emitters on poly(dimethylsiloxane) microfluidic devices. 总被引:2,自引:0,他引:2
A multichannel electrospray ionization (ESI) emitter was fabricated as part of a poly(dimethylsiloxane) (PDMS) microfluidic device using a three-layer photoresist process which also produces a self-alignment system to make a bonding between the top and bottom PDMS parts. The prototype device (2 cm high x 5 cm wide x 5 cm long) had 16-channels (30 microm wide x 50 microm deep) with emitters of 1 mm length and 60 degrees point angle. The PDMS emitter tips enabled interfacing the device to ESI-mass spectrometry; a stable electrospray from the tips was performed with limits of detection under 1 microM for reference peptides (adrenocorticotropic hormone fragment 1-17, angiotensin I and III). 相似文献
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J. L. Baker H. F. E. Huiton K. Hoepner A. W. Knapp B. G. Mc Lellan Th. v. Fellenberg Ch. Arragon J. Grossfeld H. Jaeger H. Eggers P. Hasse und Elisabeth Bake 《Fresenius' Journal of Analytical Chemistry》1924,65(10):427-432
Ohne Zusammenfassung 相似文献
39.
Walter Knapp 《Monatshefte für Chemie / Chemical Monthly》1930,56(1):66-70
Ohne Zusammenfassung 相似文献
40.
C. Brihaye T. A. Butler F. F. Knapp Jr. 《Journal of Radioanalytical and Nuclear Chemistry》1986,102(2):399-411
An evaluation of adsorbents for potential use in the191Os/191mIr medical radionuclide generator was performed. The adsorbents included 39 inorganic materials broadly classified as oxides, antimonates, ferro-ferricyanides, phosphates, sulfides, and miscellaneous including activated carbon and the organic anion-exchanger AGMP-1. The uptake of191Os in oxidation states (VI) [potassium tetrachloroosmate], (IV) [potassium hexachloroosmate] and (III) [potassium hexathiocyanatoosmate] was measured. Adsorbents having a high191Os uptake were evaluated for191mIr elution yield using three physiologically compatible eluents. Only activated carbon and AGMP-1 adsorbents showed significant191mIr elution yields under the test conditions (10% and 37%, respectively). The results of these studies suggest that activated carbon may be a promising adsorbent for development of a new191Os/191mIr medical radionuclide generator. Activated carbon is a good candidate for further development since it is inert to the chemical and radiation effects which may effect an organic based ion exchange material such as AGMP-1.Research sponsored by the Office of Health and Environmental Research, U.S. Department of Energy under contract DE-AC05-840R21400 with Martin Marietta Energy Systems, Inc. 相似文献