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71.
Physics of Atomic Nuclei - An Erratum to this paper has been published: https://doi.org/10.1134/S1063778822010082 相似文献
72.
73.
A Pd-catalyzed borylative migration methodology for cyclic enol perfluorosulfonates was applied to the synthesis of the corresponding 7-membered, azepane ring system. Throughout the optimization, it was shown that the reaction is sensitive to the nitrogen protecting group as well as the type of base and solvent. The resulting cyclic allylboronate reacts stereoselectively with aldehydes for the synthesis of novel α-hydroxyalkyl dehydroazepanes in good yield and enantioselectivity over two steps. We highlight the utility of this methodology with an efficient synthesis of the de novo 7-membered ring analogue of the piperidine alkaloid β-conhydrine. 相似文献
74.
Gondrexon N Renaudin V Petrier C Clement M Boldo P Gonthier Y Bernis A 《Ultrasonics sonochemistry》1998,5(1):1-6
In relation to design and modeling of sonochemical reactors, the hydrodynamic behaviour of a high-frequency ultrasonic reactor has been investigated. Residence time distribution (RTD) measurements have been performed by means of a tracer method. The influence of ultrasound on the response to an inlet pulse was evidenced. It was shown that the reactor behaves like a completely stirred tank reactor (CSTR) as soon as ultrasonic irradiation operates. Preliminary observations on acoustic streaming occurring within the reactor will also be presented. 相似文献
75.
Schade D Töpker-Lehmann K Kotthaus J Clement B 《The Journal of organic chemistry》2008,73(3):1025-1030
Nomega-Methylated arginines such as asymmetric dimethyl-L-arginine (ADMA) and monomethyl-l-arginine (NMMA) are known as potent physiological inhibitors of nitric oxide synthases (NOSs). To explore a possible physiological and pharmaceutical relevance of N(delta)-methylated analogues, a synthetic scheme had to be developed that would not lead to N(delta)-methyl-L-arginine only but also to its presumed metabolites of NOS catalysis. Two basic synthetic approaches have been pursued to obtain N(delta)-methylated derivatives of L-ornithine, L-citrulline, L-arginine, and N(omega)-hydroxy-L-arginine. A first attempt utilized conventionally protected L-ornithine, i.e., the tert-butyl ester and Boc-amine, and led to three end compounds in excellent yields. Simultaneous protection of the alpha-amino acid moiety by formation of boroxazolidinones, particularly by employing 9-borabicyclo[3.3.1]nonane (9-BBN-H), proved to be a convenient option to perform side chain modifications and led to all of the desired end compounds. Additionally, enantiomeric excess (ee, %) of crucial synthetic intermediates and end compounds was determined by chiral HPLC. 相似文献
76.
Philippe Clement Wolfgang Desch 《Proceedings of the American Mathematical Society》2008,136(1):333-339
We give an elementary proof for the triangle inequality of the -Wasserstein metric for probability measures on separable metric spaces. Unlike known approaches, our proof does not rely on the disintegration theorem in its full generality; therefore the additional assumption that the underlying space is Radon can be omitted. We also supply a proof, not depending on disintegration, that the Wasserstein metric is complete on Polish spaces.
77.
Clement ND Routaboul L Grotevendt A Jackstell R Beller M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(25):7408-7420
The following account summarises recent developments in the area of palladium-catalysed telomerisation and dimerisation reactions of 1,3-dienes. The most active types of catalyst, palladium-carbene complexes, were tested in pilot plant and proved to be industrially viable. 相似文献
78.
The COSY-TOF Collaboration S.?Jowzaee E.?Borodina H.?Clement E.?Doroshkevich R.?Dzhygadlo K.?Ehrhardt W.?Eyrich W.?Gast A.?Gillitzer D.?Grzonka F.?Hauenstein P.?Klaja L.?Kober K.?Kilian M.?Krapp M.?Mertens P.?Moskal J.?Ritman E.?RoderburgEmail author M.?R?der W.?Schroeder T.?Sefzick J.?Smyrski P.?Wintz P.?Wüstner 《The European Physical Journal A - Hadrons and Nuclei》2016,52(1):7
79.
J. Gr?ter P.A. Amaudruz R. Bilger P. Camerini J. Clark H. Clement E. Friedman L. Felawka S.N. Filippov E. Friagiacomo Y.K. Gavrilov E. Gibson N. Grion G.J. Hofman B. Jamieson T.L. Karavicheva M. KermaniPresent address: Sonigistix Corporation Richmond B.C. Canada VA-E--> E.L. Mathie R. Meier G. Moloney D. Ottewell J. P?tzold O. Patarakin K. Raywood R. Rui M. Schepkin M.E. Sevior G.R. Smith H. Staudenmaier R. Tacik G. Tagliente G.J. Wagner M. Yeomans 《The European Physical Journal A - Hadrons and Nuclei》1999,4(1):5-7
A search for the production of a bound trineutron state has been performed using the reaction 3He(π−,π+)nnn at incident pion energies of 65, 75, and 120 MeV. No evidence for the existence of the 3n was found, and an upper limit for the production cross section of approximately 30 nb/sr (2σ confidence level) was obtained.
Received: 22 October 1998 相似文献
80.
Sun Y. petersen J. N. Bear J. Clement T. P. Hooker B. S. 《Transport in Porous Media》1999,35(1):49-65
A mathematical model describing microbial transport and growth in a heterogeneous aquifer domain, composed of overlapping subdomains of high-permeability and low-permeability materials, is developed. Each material is conceptually visualized as a continuum which occupies the entire considered spatial aquifer domain. Based on the assumption that advection in the low-permeability domain is negligible, the mathematical model is solved by using a publically available reactive transport code. The importance of modeling microbial transport and growth in such a dual-porosity system is demonstrated through a hypothetical case study. 相似文献