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171.
Gabriella Vampa Stefania Benvenuti Fabio Severi Luca Malmusi Luciano Antolini 《Journal of heterocyclic chemistry》1995,32(1):227-234
Compounds 2, 3 and 4 were synthesized and the crystal and molecular structures of 1 and 4 were determined. An hptlc technique for studying the methylation rate of 1 and the oxidation rate of 2 was applied. 相似文献
172.
Attila G. Csszr rpd Somogyi Gabriella Pcsfalvi Pietro Traldi 《Journal of mass spectrometry : JMS》1992,27(12):1349-1356
Quantum chemical calculations were carried out at several theoretical levels (semi-empirical, MNDO; ab initio, 3–21G SCF, 6–311G** SCF and DZP CISD) to investigate the ring-opening process of and the loss of CO from the molecular ion of 5(4H)-oxazolone. The ring-opening process is predicted to be slightly endothermic and the loss of CO from the open-ring molecular ion to be slightly exothermic. Detailed population analysis calculations suggest the weakening of the lactonic C? O bond in the closed-ring molecular ion and weak carbon—carbon and nitrogen—(formy)—carbon bonds in the open form. Both the open-ring molecular ion and the [M–CO]+· ion are suggested to be of distonic type. 相似文献
173.
We construct a new family of irreducible unitary representations of a finitely generated virtually free group Λ. We prove furthermore a general result concerning representations of Gromov hyperbolic groups that are weakly contained in the regular representation, thus implying that all the representations in this family can be realized on the boundary of Λ. As a corollary, we obtain an analogue of Herz majorization principle. 相似文献
174.
Zlatić Vinko Barjašić Irena Kadović Andrea Štefančić Hrvoje Gabrielli Andrea 《Nonlinear dynamics》2020,101(3):1635-1642
Nonlinear Dynamics - Motivated by the many diverse responses of different countries to the COVID-19 emergency, here we develop a toy model of the dependence of the epidemics spreading on the... 相似文献
175.
Gabriella Butera Claudio De Pasquale Antonella Maccotta Giuseppe Alonzo Pellegrino Conte 《Cellulose (London, England)》2011,18(6):1499-1507
Use of crude oil derivatives such as diesel and gasoline is becoming unsuitable due to their detriment to environment and
to the increasing worldwide energy demand which is driving crude oil reservoirs towards exhaustion. Replacement of diesel
and gasoline with biofuels (i.e. biodiesel and bioethanol, respectively) is very desirable. In fact, biofuels are not only
environmentally sustainable, but also potentially inexhaustible due to the large amounts of waste biomasses from which they
can be retrieved. In the present study, a model compound (micro-crystalline cellulose) was dissolved in phosphoric acid and
converted at 80 °C to glucose, thereby providing the possible substrate for fermentation to bioethanol. Results revealed that
after 1 h heating, the reaction had the largest glucose yield as compared to similar studies done by using other acid catalysts.
In addition, the temperature applied here was from 40 to 60 °C lower than those already reported in literature for acid-driven
cellulose degradations. Phosphoric acid allowed both glucose and levulinic acid achievement. The latter is usually used to
synthesize fuel additives, catalysts, solvents and herbicides, thereby enhancing the added value of the conversion of cellulose
to glucose in phosphoric acid. Finally, 1H T1 NMR relaxometry showed its suitability to monitor cellulose degradation. The advantages of relaxomety are its quickness since
only few minutes are needed to obtain relaxograms, and the possibility to use raw mixtures without the needing of sample preparation. 相似文献
176.
Antonino Lauria Annalisa Guarcello Gabriella Macaluso Anna Maria Almerico 《Tetrahedron letters》2009,50(52):7333-1004
The reactivity of asymmetric benzo-condensed diazines in the 1,3-dipolar cycloaddition reactions with nitrilimines was investigated. The results demonstrated that, at variance with the symmetric quinoxaline, a certain grade of diastereoselectivity emerged. Moreover in the case of the 5-methylquinoxaline and quinazoline a mono-cycloadduct was obtained. 相似文献
177.
Dr. Peterson de Andrade Dr. Juan C. Muñoz-García Dr. Giulia Pergolizzi Valeria Gabrielli Dr. Sergey A. Nepogodiev Dr. Dinu Iuga László Fábián Rinat Nigmatullin Dr. Marcus A. Johns Dr. Robert Harniman Prof. Stephen J. Eichhorn Dr. Jesús Angulo Prof. Yaroslav Z. Khimyak Prof. Robert A. Field 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(4):1374-1382
Understanding the fine details of the self-assembly of building blocks into complex hierarchical structures represents a major challenge en route to the design and preparation of soft-matter materials with specific properties. Enzymatically synthesised cellodextrins are known to have limited water solubility beyond DP9, a point at which they self-assemble into particles resembling the antiparallel cellulose II crystalline packing. We have prepared and characterised a series of site-selectively fluorinated cellodextrins with different degrees of fluorination and substitution patterns by chemoenzymatic synthesis. Bearing in mind the potential disruption of the hydrogen-bond network of cellulose II, we have prepared and characterised a multiply 6-fluorinated cellodextrin. In addition, a series of single site-selectively fluorinated cellodextrins was synthesised to assess the structural impact upon the addition of one fluorine atom per chain. The structural characterisation of these materials at different length scales, combining advanced NMR spectroscopy and microscopy methods, showed that a 6-fluorinated donor substrate yielded multiply 6-fluorinated cellodextrin chains that assembled into particles presenting morphological and crystallinity features, and intermolecular interactions, that are unprecedented for cellulose-like materials. 相似文献
178.
Czechoslovak Mathematical Journal - We give a graph theoretic interpretation of r-Lah numbers, namely, we show that the r-Lah number $${\left\lfloor {\matrix{n \cr k \cr } } \right\rfloor _r}$$... 相似文献
179.
Prof. Gabriella Salviulo Prof. Maria Cristina Lavagnolo Prof. Manuele Dabalà Prof. Enrico Bernardo Prof. Antonino Polimeno Prof. Mauro Sambi Prof. Franco Bonollo Prof. Silvia Gross 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(22):6676-6695
Circular economy is considered a new chance to build a more sustainable world from both the social and the economic point of view. In this Essay, the possible contribution of inorganic chemistry towards a smooth transition to circularity in inorganic materials design and production is discussed by adopting an interdisciplinary approach. 相似文献