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91.
Artuso F D'Archivio AA Lora S Jerabek K Králik M Corain B 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(21):5292-5296
The microporous (gel-type) functional resin co-poly-N,N-dimethylacrylamide (DMAA) (88 % mol)/methacrylic acid (MAA) (8 % mol)/N,N'-methylenebisacrylamide (MBAA) (4 % mol) (MPIF(H)) is employed as the hosting framework for the production of resin-supported Pd(0) nanoclusters. The obtained composite MPIF(-)Na(+)/Pd(0) is prepared upon reducing, in ethanol, MPIF(-)Pd(2+) (0.5), obtained upon previous homogeneous dispersion of "Pd(2+)" inside the resin particles (XRMA control) through ion-exchange. Metal nanoclusters appear to be size-controlled (2.0+/-0.2 nm) and are seen to reasonably fit the predominant resin "nanopores" diameter, determined in ethanol (3.2 nm) by means of inverse steric exclusion chromatography (ISEC). 相似文献
92.
Mario Bianchi Enrico Husermann Silvano Rossi 《Journal of heterocyclic chemistry》1979,16(7):1411-1416
The chemical behavior of 4-methyl and 4-phenyl-5-oxo-1H-4,5-dihydro-1,2,4-benzotriazepines towards methylating and acidic agents has been investigated. The 4-methyl derivative, when treated with methyl fluorosulfonate furnished, after crystallization from water, a quaternary salt (2,4-dimethyl-5-oxo-1H-4,5-dihydro-1,2,4-benzotriazepinium fluorosulfonate), whereas from the 4-phenyl derivative, a complex mixture was obtained, which, after boiling with water, afforded 2-methylindazolone, aniline fluorosulfonate and formic acid. In acidic medium the 4-methyl derivative underwent an isomerization reaction yielding 1-imino-3-methylquinazolin-4-one, but the 4-phenyl derivative exclusively yielded products resulting from ring opening. In alkaline medium, both compounds gave hydrolytic cleavage products. 相似文献
93.
Jérémy Barbé Jessica Eid Erik Ahlswede Stefanie Spiering Michael Powalla Rakesh Agrawal Silvano Del Gobbo 《Journal of nanoparticle research》2016,18(12):379
Cu(In,Ga)Se2 (CIGSe) thin film solar cells were fabricated by direct inkjet printing of Cu(In,Ga)S2 (CIGS) nanoparticles followed by rapid thermal annealing under selenium vapor. Inkjet printing is a low-cost, low-waste, and flexible patterning method which can be used for deposition of solution-based or nanoparticle-based CIGS films with high throughput. XRD and Raman spectra indicate that no secondary phase is formed in the as-deposited CIGS film since quaternary chalcopyrite nanoparticles are used as the base solution for printing. Besides, CIGSe films with various Cu/(In + Ga) ratios could be obtained by finely tuning the composition of CIGS nanoparticles contained in the ink, which was found to strongly influence the devices performance and film morphology. To date, this is the first successful fabrication of a solar device by inkjet printing of CIGS nanoparticles. 相似文献
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96.
Silvano Martello 《Central European Journal of Operations Research》2010,18(1):47-58
We discuss some relevant results obtained by Egerváry in the early Thirties, whose importance has been recognized several years later. We start with a quite well-known historical fact: the first modern polynomial-time algorithm for the assignment problem, invented by Harold W. Kuhn half a century ago, was christened the “Hungarian method” to highlight that it derives from two older results, by Kőnig (Math Ann 77:453–465, 1916) and Egerváry (Mat Fiz Lapok 38:16–28, 1931) (A recently discovered posthumous paper by Jacobi (1804–1851) contains however a solution method that appears to be equivalent to the Hungarian algorithm). Our second topic concerns a combinatorial optimization problem, independently defined in satellite communication and in scheduling theory, for which the same polynomial-time algorithm was independently published 30 years ago by various authors. It can be shown that such algorithm directly implements another result contained in the same 1931 paper by Egerváry. We finally observe that the latter result also implies the famous Birkhoff-von Neumann theorem on doubly stochastic matrices. 相似文献
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98.
Silvano Matarasso 《Annali di Matematica Pura ed Applicata》1976,109(1):39-87
Summary In this paper are studied existence and unicity of solutions of a class of hypoelliptic problems.
Entrata in Redazione il 20 novembre 1974.
Lavoro eseguito nell'ambito del Gruppo Nazionale per l'Analisi Funzionale e le sue Applicazioni del C.N.R. 相似文献
Entrata in Redazione il 20 novembre 1974.
Lavoro eseguito nell'ambito del Gruppo Nazionale per l'Analisi Funzionale e le sue Applicazioni del C.N.R. 相似文献
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100.
A. Paul Krapcho Mary E. Petry John J. Landi John Stallman Johanna F. Polsenberg Miles P. Hacker Silvano Spinelli Ambrogio Oliva Roberto Di Domenico Emesto Menta 《Journal of heterocyclic chemistry》1993,30(6):1565-1569
The synthesis of 6,9-difluorobenzo[g]quinoline-5,10-dione ( 3b ) is described. Facile ipso substitutions of the fluorides from 3b by diamines readily yield the corresponding 6,9-bis[(aminoalkyl)amino]benzo-[g]quinoline-5,10-diones 2 . The analogue 2d has been synthesized by side arm modifications of dione 8a . 相似文献