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91.
Astrid Ollech 《International Journal of Theoretical Physics》1995,34(8):1647-1652
The problem I consider originates from Dörfler, who found a construction to assign an Orthocomplemented latticeH(G) to a graphG. By Dörfler it is known that for every finite Orthocomplemented latticeL there exists a graphG such thatH(G)=L. Unfortunately, we can find more than one graphG with this property, i.e., orthocomplemented lattices which belong to different graphs can be isomorphic. I show some conditions under which two graphs have the same orthocomplemented lattice. 相似文献
92.
93.
D. Alber O. Boebel C. Schwarz H. Duwe D. Hilscher H. Homeyer U. Jahnke B. Spellmeyer 《Zeitschrift für Physik A Hadrons and Nuclei》1989,333(3):319-320
We have searched for neutrons from a Pd-electrode loaded with deuterium in electrolysis setups similar to those of Fleischmann and Pons [1] and Jones et al. [2]. Within the sensitivity of our neutron detection system corresponding to a neutron source strength of 5 x 10? 2 neutrons/s we did not find any neutrons due to ‘cold nuclear fusion’. We emphasize the necessity of using several independent neutron detectors. 相似文献
94.
Astrid Lambrecht 《Physik in unserer Zeit》1997,28(2):88-88
Die Nachricht von den ersten Realisierungen von Bose-Einstein-Kondensaten aus schwach wechselwirkenden Atomen im Sommer 1995 [1,2] (siehe auch Physik in unserer Zeit, 27, 200 (5/1996)) zog eine Welle neuer Forschungsaktivitäten nach sich. Wolfgang Ketterle vom Massachusetts Institute of Technology, MIT, und Kollegen gelang es kürzlich, zwei Bose-Einstein-Kondensate zur Interferenz zu bringen [3]. 相似文献
95.
Uwe Kempin Lothar Hennig Dietmar Knoll Peter Welzel Dietrich Müller Astrid Markus Jean van Heijenoort 《Tetrahedron》1997,53(52):1594-17690
Moenomycin A (18) on reaction with the diazonium salt derived from bifunctional (protected) 15 yields the coupling product 19 which on reduction is converted into the moenomycin thiol derivative 21. Thiol 21 has been used to prepare selectively moenomycin dansyl and biotin adducts 26 and 28, respectively. This work was performed with the aim to use moenomycin as a tool for studies of the transglycosylation step in peptidoglycan biosynthesis. 相似文献
96.
97.
98.
Goldenbaum F Bohne W Eades J Egidy Tv Figuera P Fuchs H Galin J Golubeva YS Gulda K Hilscher D Iljinov AS Jahnke U Jastrzebski J Kurcewicz W Lott B Morjean M Pausch G Péghaire A Pienkowski L Polster D Proschitzki S Quednau B Rossner H Schmid S Schmid W Ziem P 《Physical review letters》1996,77(7):1230-1233
99.
P. Figuera W. Bohne B. Drescher F. Goldenbaum D. Hilscher U. Jahnke B. Lott L. Pienkowski P. Ziem 《Zeitschrift für Physik A Hadrons and Nuclei》1995,352(3):315-320
By using two 4 detector systems for charged particles and neutrons, we measured the evaporated light particles emitted in coincidence with evaporation residues (ER) produced in the reaction32S+58Ni atE(32S) 820 MeV. From the analysis of the light particle multiplicities as a function of the ER velocity, we extracted the maximum excitation energy reached in fusion evaporation reactions for the studied system.Supported by the European Community Programme Human Capital and Mobility 相似文献
100.
Kari Dahl Astrid Hald Poul J?rgensen Ivar Martinsen Yngvar Thomassen 《Fresenius' Journal of Analytical Chemistry》1990,338(4):526-529
Summary Studies have been made of both short and long term stability of trace elements in lyophilized human body fluid reference materials, as well as the stability of mercury in reconstituted urine solutions. No detectable concentration changes for mercury, lead and aluminium occurred during the 5-year period. There are large differences in the amounts of mercury loss among different reconstituted materials. Addition of traces of gold to the solutions minimized the mercury loss and increased the useable time of the reconstituted material from hours to 8 days. A certification process based on direct determinations by reference laboratories and by comparison against master lots of the same material and against similar certified reference materials is presented. Values for calcium, copper and mercury obtained from reference laboratories and using the data transfer principle have been assigned in new batches of urine and serum. 相似文献