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1.
Results from Super-Kamiokande-I’s entire 1496 live days of solar neutrino data are presented, including the absolute flux, energy spectrum, zenith angle (day/night) and seasonal variation. The possibility of MSW and vacuum oscillations is discussed in light of these results. Results from the first 1289 days of Super-K-I’s atmospheric neutrino analysis are also presented, including the evidence for νμν τ oscillations, against νμ → νsterile oscillations, and the current limits on proton decay. Finally, results based on 56 × 1019 protons on target are given for the K2K long-baseline neutrino oscillation experiment.  相似文献   
2.
[reaction: see text]. The regioselective and enantiospecific rhodium-catalyzed allylic amination of secondary allylic carbonates 1 with N-(arylsulfonyl)anilines provides a convenient process for the construction of arylamines 2. This method, in conjunction with ring-closing metathesis and radical cyclization reactions, allows the direct construction of biologically relevant pharmacophores as exemplified by the construction of dihydroquinoline and dihydrobenzo[b]indoline derivatives.  相似文献   
3.
An efficient synthesis of 1,3,5-trisubstituted benzenes via a sequential Pd-mediated carbon-sulfur, carbon-nitrogen, and carbon-carbon bond formation reactions is reported. Selective amidation and sulfonamidation reactions are accomplished via Pd-catalyzed reactions between aryl chlorides and an acetamide or a methanesulfonamide.  相似文献   
4.
Due to the growing popularity of distributed computing systems and the increased level of modelling activity in most organizations, significant benefits can be realized through the implementation of distributed model management systems (DMMS). These systems can be defined as a collection of logically related modelling resources distributed over a computer network. In several ways, functions of DMMS are isomorphic to those of distributed database systems. In general, this paper examines issues viewed as central to the development of distributed model bases (DMB). Several criteria relevant to the overall DMB design problem are discussed. Specifically, this paper focuses on the problem of distributing decision models and tools (solvers), henceforth referred to as theModel Allocation Problem (MAP), to individual computing sites in a geographically dispersed organization. In this research, a 0/1 integer programming model is formulated for the MAP, and an efficient dual ascent heuristic is proposed. Our extensive computational study shows in most instances heuristic-generated solutions which are guaranteed to be within 1.5–7% of optimality. Further, even problems with 420 integer and 160,000 continuous variables took no more than 60 seconds on an IBM 3090-600E computer.  相似文献   
5.
6.
Preparation of oxadiazinones 2 , from α-anilinoacetophenone oximes and O-carbamoyl-2,3-dihydro-4-quinolinone oximes 3 , from quinolinones are described.  相似文献   
7.
8.
An efficient synthesis of biaryl building blocks with multiple point diversities via a Suzuki cross-coupling reaction using a commercially available preformed Pd catalyst 1 was reported. Substituted biaryl anilines and phenols were obtained in one step from commercially available aryl halides.  相似文献   
9.
A large number of pyridinecarboxaldehyde (and ketone) O-substituted oximes were prepared by alkylating the oxime or by treating the parent aldehyde (or ketone) with an O-substituted hydroxylamine. Many of these were converted to the N-oxide. Screening revealed that many of these oxime ethers were active in preventing gastric ulcers in rats. Data on selected examples is given.  相似文献   
10.
Seven series of as-triazino[4,3-a] [1,4]benzodiazepines were prepared which differed in the degree of unsaturation or the nature and position of oxygen function on the triazino ring. These were prepared by closing the triazino ring of appropriately substituted hydrazones from 2-hydrazinobenzodiazepines or by condensing substituted hydrazines with 2-thiobenzodiazepines. Most of these represent new ring systems. They were tested in a battery of tests designed to uncover central nervous system activities. Most of the activity was found in tests thought to be indicative of anxiolytic, hypnotic or sedative potential. Five of the series contained members more active than the standard, diazepam, and a few of the compounds were among the most potent benzodiazepines known. Some of the intermediate benzodiazepine hydrazones were also active.  相似文献   
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