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951.
K. Bruce Erickson 《Probability Theory and Related Fields》1981,57(4):535-558
Summary Let 0<h() and {S
n} a renewal process. We find conditions under which ast
wherem=ES
1, (t) = min (nS
n>t}. We apply these results to obtain sample path representation of local time at a point for a Markov process.Research supported in part by a grant from the National Science Foundation, USA 相似文献
952.
Two on-line configurations using multiple 6- and 10-port valves were investigated for high-flow on-line extraction of a basic drug in rat plasma and human urine using a reversed-phase and a cation-exchange SPE sorbent. The first configuration studied was a single reversed-phase extraction cartridge (2.1 x 20 mm, 25 microm) using an optimized washing protocol. The results showed that up to 1.5 mL of sample (urine or plasma diluted 1:1) can be injected with limits of quantification (LOQs) as low as 100 pg/mL. The second configuration studied was the combination of a cation exchanger and a reversed-phase cartridge using at-column dilution. The results showed better LOQs than those obtained with the single cartridge at 10 pg/mL with the same injection volume. The mass spectrometer was operated in the multiple reaction monitoring (MRM) mode. All calibration curves gave an average of 5% relative standard deviation (RSD). 相似文献
953.
[reaction: see text] L-Proline-catalyzed direct asymmetric Mannich reactions of N-PMP protected alpha-imino ethyl glyoxylate with various alpha,alpha-disubstituted aldehydes affords quaternary beta-formyl alpha-amino acid derivatives with excellent yields and enantioselectivities. The Mannich products are further converted to the corresponding quaternary alpha- and beta-amino acids and beta-lactams. 相似文献
954.
Christiane Yoakim Nathalie Goudreau GrahamA. McGibbon Jeff O'Meara PeterW. White WilliamW. Ogilvie 《Helvetica chimica acta》2003,86(10):3427-3444
A novel series of inhibitors of the HPV11 E1? E2 protein? protein interaction was identified. These inhibitors, which were discovered as a result of high‐throughput screening, feature an indandione system spiro‐fused onto an appropriately substituted tetrahydrofuran ring. Early stability studies indicated, surprisingly, that this particular series of compounds were readily converted, in binding assay buffer, to the corresponding carboxylates. NMR and mass spectrometry techniques were used to elucidate the structures of these products and the mechanism by which they are produced. 相似文献
955.
elements of some (finite) poset , write for the probability that precedes in a random (uniform) linear extension of . For define
where the infimum is over all choices of and distinct .
Addressing an issue raised by Fishburn [6], we give the first nontrivial lower bounds on the function . This is part of a more general geometric result, the exact determination of the function
where the infimum is over chosen uniformly from some compact convex subset of a Euclidean space.
These results are mainly based on the Brunn–Minkowski Theorem and a theorem of Keith Ball [1], which allow us to reduce to
a 2-dimensional version of the problem.
Received: October 6, 1997 相似文献
956.
Condo GT Handler T Shimony J Abe K Austern M Armenteros R Bacon TC Ballam J Bingham HH Brau JE Braune K Brick D Bugg WM Butler JM Cameron W Cohn HO Colley DC Dado S Diamond R Dingus P Erickson R Falicov A Field RC Fortney LR Franek B Fujiwara N Glanzman T Godfrey IM Goldberg JJ Goshaw AT Hall G Hancock ER Hargis HJ Hart EL Harwin MJ Hasegawa K Hulsizer RI Jobes M Kafka T Kalmus GE Kelsey DP Kent J Kitagaki T Levy A Lucas PW Mann WA McCrory ES Merenyi R Milburn R Milstene C Moffeit KC Napier A 《Physical review D: Particles and fields》1990,41(11):3317-3323
957.
Condo GT Handler T Shimony J Abe K Armenteros R Austern M Bacon TC Ballam J Bingham HH Brau JE Braune K Brick D Bugg WM Butler JM Cameron W Cohn HO Colley DC Dado S Diamond R Dingus P Erickson R Falicov A Field RC Fortney LR Franek B Fujiwara N Glanzman T Godfrey IM Goldberg JJ Goshaw AT Hall G Hancock ER Hargis HJ Hart EL Harwin MJ Hasegawa K Hulsizer RI Jobes M Kafka T Kalmus GE Kelsey DP Kent J Kitagaki T Levy A Lucas PW Mann WA McCrory ES Merenyi R Milburn R Milstene C Moffeit KC Napier A 《Physical review D: Particles and fields》1991,43(9):2787-2791
958.
959.
Zhengrong Zhou Melissa M. Reynolds Jeff W. Kampf Mark E. Meyerhoff 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(1):o1-o2
The title compound, C10H24N6O4, is the most stable type of nitric oxide (NO) donor among the broad category of discrete N‐diazeniumdiolates (NO adducts of nucleophilic small molecule amines). Sitting astride a crystallographic inversion center, the molecule contains a symmetric dimethylhexane‐1,6‐diamine structure bearing two planar O2‐methylated N‐diazeniumdiolate functional groups [N(O)=NOMe]. These two groups are parallel to each other and have the potential to release four molecules of NO. The methylated diazeniumdiolate substituent removes the negative charge from the typical N(O)=NO− group, thereby increasing the stability of the diazeniumdiolate structure. The crystal was nonmerohedrally twinned by a 180° rotation about the real [101] axis. This is the first N‐based bis‐diazeniumdiolate compound with a flexible aliphatic main unit to have its structure analyzed and this work demonstrates the utility of stabilizing the N‐diazeniumdiolate functional group by methylation. 相似文献
960.
D.H. Lu M. Yi S.-K. Mo J.G. Analytis J.-H. Chu A.S. Erickson D.J. Singh Z. Hussain T.H. Geballe I.R. Fisher Z.-X. Shen 《Physica C: Superconductivity and its Applications》2009,469(9-12):452-458
We report a comparison study of LaOFeP and LaOFeAs, two parent compounds of recently discovered iron-pnictide superconductors, using angle-resolved photoemission spectroscopy. Both systems exhibit some common features that are very different from well-studied cuprates. In addition, important differences have also been observed between these two ferrooxypnictides. For LaOFeP, quantitative agreement can be found between our photoemission data and the LDA band structure calculations, suggesting that a weak coupling approach based on an itinerant ground state may be more appropriate for understanding this new superconducting compound. In contrast, the agreement between LDA calculations and experiments in LaOFeAs is relatively poor, as highlighted by the unexpected Fermi surface topology around (π, π). Further investigations are required for a comprehensive understanding of the electronic structure of LaOFeAs and related compounds. 相似文献