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31.
The present paper reports that TL glow curve and kinetic parameter of Eu3+ doped SrY2O4 phosphor irradiated by beta source. Sample was prepared by solid state preparation method. Sample was characterized by XRD analysis and particle size was calculated by Debye–Scherrer formula. The sample was irradiated with Sr-90 beta source giving a dose of 10 Gy and the heating rate used for TL measurements are 6.7 °C/s. The samples display good TL peaks at 106 °C, 225 °C and 382 °C. The corresponding kinetic parameters are calculated. The photoluminescence excitation spectrum at 247 and 364 nm monitored with 400 nm excitation and the corresponding emission peaks at 590, 612 and 624 nm are reported. 相似文献
32.
A fairly sensitive spectrophotometric method for the determination of ibuprofen, ketoprofen, piroxicam, diclofenac sodium, mefenamic acid or enfenamic acid in bulk samples and pharmaceutical preparations is described, based on the formation of a chloroform-soluble, coloured ion-association complex between the drug and Methylene Violet at pH 7.6. 相似文献
33.
G. Saravanan M. V. Suryanarayana Manoj J. Jadhav M. Ravikumar N. Someswararao P. V. R. Acharyulu 《Chromatographia》2007,66(5-6):435-438
This present work narrates the stress stability behavior and development of a liquid chromatographic method for the quantitative
determination of anastrozole. Anastrozole is appropriately used when using substantial amounts of aromatizing steroids, or
when one is prone to gynecomastia and using moderate amounts of such steroids. A chromatographic separation was achieved on
a Hichrom RPB18 (250 × 4.6 mm, 5 μ) column using water and mixture of acetonitrile and methanol (1:1 ratio) as mobile phase.
Forced degradation studies were performed on bulk samples of anastrozole using acid, base, hydrogen peroxide, heat and UV
light. Degradation of the drug substance was observed in base hydrolysis. Degradation product formed under base hydrolysis
was found to be Imp-C. The sample solution and mobile phase were found to be stable up to 48 h. The developed method was validated
with respect to linearity, accuracy, precision, robustness and forced degradation studies prove the stability indicating power
of the method. 相似文献
34.
35.
Dierk Knittel V. Suryanarayana Rao 《Monatshefte für Chemie / Chemical Monthly》1986,117(10):1185-1193
Cathodic reduction of -azidochalcones under slightly protic conditions proves to be an excellent method for a selective conversion of the azido function to an amino group without affecting other reducible parts of the molecules. The amino-propenones retain theZ-configuration about the C=C-bond of the starting material, whereas N-acetyl derivatives, obtained under mildly acetylating conditions, are partially isomerised. The low reduction potential of N,N-diacetyl-enamines of this type prevents their direct one step synthesis by electrolysis of azidochalcones under strongly acetylating conditions. The voltammetric behaviour of the azides and their reduction pathway is discussed.
Elektrolytische Untersuchungen an Vinylaziden, 6. Mitt.Elektrolytische Reduktion von Azidochalkonen
Zusammenfassung Die kathodische Reduktion von -Azidopropenon erweist sich als ausgezeichneter Weg, um selektiv zu Enaminen zu gelangen, ohne (wie chemische Reduktionsmittel) auch andere Gruppierungen anzugreifen. Durch die Kontrolle von Protonierungs- bzw. Acetylierungsschritten lassen sich die stabileren N-Acetylamine erhalten. Das niedrig liegende Reduktionspotential der N,N-Diacetylamino-propenone verhindert, daß sie in einer Einstufensynthese bei der Reduktion der Azidochalkone unter stark acylierenden Bedingungen erhältlich sind. Das voltammetrische Verhalten der Azide und ihr Reaktionsweg bei der kathodischen Reduktion werden diskutiert.相似文献
36.
P. J. Kaiser M. B. Suryanarayana 《Journal of Optimization Theory and Applications》1976,19(1):141-164
This paper focuses on the interplay between seminormality requirements and convergence hypotheses on trajectories in the lower closure theorems for orientor field equations. With the use of a weak form of seminormality, called the intermediate property (Q*), we obtain lower closure theorems (and thereby closure theorems) for orientor field equations in Banach spaces, under the assumption of strong convergence of some coordinates of the trajectories, while only weak convergence is assumed in the others. In the Euclidean case, this requirement of property (Q*) is further reduced to mere Kuratowski property (K), under the usual growth-type conditions. Finally, in the appendix, property (Q*) is investigated in detail.This research has been partially supported by Research Project AFOSR-71-2122 at the University of Michigan, Ann Arbor, Michigan. 相似文献
37.
M. B. Suryanarayana 《Journal of Optimization Theory and Applications》1976,19(1):125-140
In the context of a recent geometric condition of Cesari, used in the reduction of seminormality requirements in lower closure theorems, this paper shows that the existence of a strongly convergent selection from the sequence of orientor fields, under Kuratowski property (K), is adequate to guarantee lower closure theorems. This generalization is justified through examples. Several related remarks are made.This work was done in the framework of Research Project AFOSR-71-2122 at the University of Michigan, Ann Arbor, Michigan. The author wishes to thank Professor L. Cesari for helpful discussions during the writing of this paper. 相似文献
38.
39.
The cathodic preparation of enamino ketones from enazidoketones has been generalised to include heteroaromatic and aliphatic derivatives. Mechanistically the role of different sites of protonation, either on N1 of the N3-group or on carbonyl depending on electrolysis potential and acid strength, apparent by product distribution, is clarified. Aldehydic groups are preferentially reduced compared to the vinylazide part. Purely aliphatic azidoketones yield conjugated dienes under reductive acetylation, which might be useful for cycloaddition reactions.Die kathodische Synthese von Enaminoketonen aus ungesättigten Azidoketonen wurde auf heteroaromatisch substituierte und auf rein aliphatische Derivate übertragen. Zum Reduktionsmechanismus wurde der Einfluß verschiedener Stellen der Protonierung (am N1 der N3-Gruppe bzw. an der Carbonylgruppe), abhängig von Potential und Säurestärke, untersucht. Aldehydische Gruppen als weitere funktionelle Gruppen im Enazid werden leichter als die Vinylazide reduziert. Die rein aliphatischen Enazidoketone ergeben bei reduktiver Acylierung konjugierte Diene.
Elektrolytische Untersuchungen an Vinylaziden, 7. Mitt.: Kathodische Synthese von 2-Amino-2-propen-1-onen相似文献
40.
T. Axenrod C. M. Watnick M. J. Wieder S. Duangthai G. A. Webb H. J. C. Yeh S. Bulusu M. M. King 《Magnetic resonance in chemistry : MRC》1982,20(1):11-15
The 1J(15N13C) values for a series of ring-substituted N,N-dimethylaniline-15N derivatives and a series of nitrobenzene-15N derivatives were measured from the 13C spectra. In the nitrobenzenes, small changes in 1J(15N13C) are attributed to the inductive effect of the substituents, since steric inhibition of conjugation has little effect on the magnitude of the coupling. In contrast, steric inhibition of nitrogen lone-pair delocalization in N,N-dimethylaniline derivatives markedly reduces the value of 1J(15N13C). Theoretical calculations of 1J(15N13C) values for the two series of compounds were made using standard INDO parameters and a ‘sum-over-states’ perturbation approach. Fair agreement between the calculated and experimental values is found. 相似文献