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1.
A. Heidenreich I. Schek D. Scharf J. Jortner 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1991,20(1):227-229
The time resolved dynamics of diffusionless cube → ring isomerization of the Na4Cl4 cluster was interrogated by constant energy molecular dynamics simulations, utilizing the first passage time method. The nonreactive isomerization induced by nonselective vibrational excitation is well accounted for in terms of the statistical RRK theory, opening avenues for experimental exploration of time-resolved cluster isomerization dynamics. 相似文献
2.
Rainer Scharf 《Chaos, solitons, and fractals》1995,5(12):2527-2549
Perturbing soliton-bearing completely integrable dynamics can give rise to rich and fascinating behaviour. If the perturbation introduces a lengthscale which is large compared to the spatial extent of the solitons present in the system, the solitons move like particles in an effective potential. Taking into account two-soliton interaction can result in chaotic behaviour called ‘soliton chaos’. In the opposite limit of a small-lengthscale perturbation the solitons acquire a dressing which effectively shields them from the perturbation. If the resulting ‘dressed solitons’ are subject to an additional long-wavelength perturbation they move like renormalised particles. Furthermore they can scatter nearly elastically. If the perturbation contains lengthscales which are comparable to one of the soliton's typical lengthscales then lengthscale competition can occur. Neither the particle approximation nor the dressed-particle approximation for the soliton is valid and complicated spatio-temporal behaviour is observed. We illustrate this scenario by means of the perturbed nonlinear Schrödinger equation. The perturbed sine-Gordon equation and the Ablowitz-Ladik equation are also discussed. 相似文献
3.
Peter Esser Bettina Pohlmann Hans-Dieter Scharf 《Angewandte Chemie (International ed. in English)》1994,33(20):2009-2023
The light of the sun can be used directly for changing chemical structures photochemically. Any industrial application must conform to the limitations imposed by the spectral distribution of the photons from the sun, the interruptions to the radiation due to the day/night rhythm, and the weather. In this review, we describe the photochemical potential of the sun, give a fundamental treatment of the concept of photoreactors driven by sunlight (abbreviated to solar photoreactors), and give an account of the realization of this concept in the first pilot plant on the “Plataforma Solar de Almeria” in southern Spain and in other activities in this field. Based on experimental data from photochemical investigations on the pilot plant scale, possibilities, limitations, and the potential growth of solar photochemistry are described. Solar photochemistry, in our opinion, is a technique which could make a contribution to the chemistry of the future because of its photochemical synthesis potential, the avoidance of waste products, and the direct utilization of the sun, not only as a primary energy source, but also as a reaction partner. 相似文献
4.
5.
The Nature of the vibronic intensity borrowing mechanism in the 1B3u(n)1Ag() transition of pyrazine
The transition intensities of the S0S1 gas phase absorption spectra of pyrazine-d0 and -d4 were carefully measured. A discussion of the various aspects of vibronic intensity borrowing for this unique case is presented using our new experimental results. 相似文献
6.
Dr. H. -D. Scharf Dr. H. Meichelbeck Prof. Dr. H. Zahn 《Colloid and polymer science》1979,257(2):145-155
Zusammenfassung Wolle und-Keratose wurden mit Carbonsäure-chloriden in Dimethylsulfoxid mit Pyridinzusatz oder ohne Base bei 20–60 °C bis zu 4 Stunden umgesetzt. Die dabei eintretende Vernetzungsreaktion beruht auf der Bildung von Formaldehyd aus den Säurechloriden und Dimethylsulfoxid. Damit werden auch die Anafysendaten verständlich: geringe Gewichtsänderungen, Beteiligung des Lysins, keine Beteiligung der Carboxylgruppen, Verschwinden des Tyrosins erst nach saurer Totalhydrolyse. Läßt man Acylchloride in Dimethylformamid, Dimethylacetamid, Hexamethyl-phosphorsäuretriamid,-Butyrolacton und Methyl-pyrrolidon auf Wolle einwirken, so erfolgt N,O-Acylierung unter Gewichtszunahme.
Teil der DissertationH.-D. Scharf, RWTH Aachen, 1972; 21. Mitteilung über ,Reaktivität von Aminosäureseitenketten. 20. Mitteilung vgl.W. Wellner, D. Nissen und H. Zahn, Colloid u. Polymer Sci.255, 444 (1977).
Jetzt Dynamit-Nobel AG., Troisdorf.
Jetzt Wella AG, Darmstadt.
Mit 4 Abbildungen und 8 Tabellen 相似文献
Summary Wool and -Keratose were reacted at 20–60° for 4 hours with acylchlorides in dimethylsulfoxide with addition of pyridine or without a base. The ensuing crosslinking reaction. was due to formation of formaldehyde by reaction of the acid chlorides with the solvent dimethylsulfoxide. This explains the analytical data found: small weight changes participation of lysine, no participation of the carboxylic groups, disappearance of tyrosine during the acid hydrolysis.If the acyl chlorides are reacted with wool in the solvents dimethylformamide, dimethylacetamide, hexamethyl-phosphortriamide,-butyrolacton and methyl-pyrrolidone, normal acylation and corresponding weight increases were found.
Teil der DissertationH.-D. Scharf, RWTH Aachen, 1972; 21. Mitteilung über ,Reaktivität von Aminosäureseitenketten. 20. Mitteilung vgl.W. Wellner, D. Nissen und H. Zahn, Colloid u. Polymer Sci.255, 444 (1977).
Jetzt Dynamit-Nobel AG., Troisdorf.
Jetzt Wella AG, Darmstadt.
Mit 4 Abbildungen und 8 Tabellen 相似文献
7.
We consider Albrecht's theory for Raman scattering of fundamentals in the far and pre-resonance regions. Destructive interferences inherent to the A and B terms augment the conventionally suppressed C term dramatically. Raman excitation profiles for the ν1(a1g) and ν6(e2g fundamentals in benzene can be well fitted with theoretical C-term profiles involving the 1E1u(π-π*) state at 1800 A. 相似文献
8.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baden A Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM Casey D Castilla-Valdez H 《Physical review letters》1995,75(6):1023-1027
9.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baden A Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Bloom P Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM Casey D Castilla-Valdez H 《Physical review letters》1995,75(8):1456-1461
10.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baden A Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM Casey D Castilla-Valdez H 《Physical review letters》1995,75(4):618-623