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11.
Andreu Presa Rosa F. Brissos Ana Belén Caballero Ivana Borilovic Dr. Luís Korrodi‐Gregório Prof. Ricardo Pérez‐Tomás Dr. Olivier Roubeau Prof. Patrick Gamez 《Angewandte Chemie (International ed. in English)》2015,54(15):4561-4565
The photoactivation of potential anticancer metal complexes is a hot topic of current research as it may lead to the development of more selective drugs. Photoactivated chemotherapy (PACT) with coordination compounds is usually based on a (photo)chemical reaction taking place at the metal center. Herein, a new strategy is exploited that consists of “photomodifying” a ligand coordinated to metal ions. Platinum(II) complexes from photoswitchable 1,2‐dithienylethene‐containing ligands have been prepared, which exhibit two interconvertible photoisomeric forms that present distinct DNA‐interacting properties and cytotoxic behaviors. 相似文献
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Julio López Sebastián Maldonado Ricardo Montoya 《The Journal of the Operational Research Society》2017,68(11):1323-1334
Support vector machines (SVMs) have been successfully used to identify individuals’ preferences in conjoint analysis. One of the challenges of using SVMs in this context is to properly control for preference heterogeneity among individuals to construct robust partworths. In this work, we present a new technique that obtains all individual utility functions simultaneously in a single optimization problem based on three objectives: complexity reduction, model fit, and heterogeneity control. While complexity reduction and model fit are dealt using SVMs, heterogeneity is controlled by shrinking the individual-level partworths toward a population mean. The proposed approach is further extended to kernel-based machines, conferring flexibility to the model by allowing nonlinear utility functions. Experiments on simulated and real-world datasets show that the proposed approach in its linear form outperforms existing methods for choice-based conjoint analysis. 相似文献
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We discuss the local dynamics of a subgroup of \({{\mathrm{Diff}}\, ({{\mathbb {C}}}^2, 0)}\) possessing locally discrete orbits as well as the structure of the recurrent set for more general groups. It is proved, in particular, that a subgroup of \({{\mathrm{Diff}}\, ({{\mathbb {C}}}^2, 0)}\) possessing locally discrete orbits must be virtually solvable. These results are of considerable interest in problems concerning integrable systems. 相似文献
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The generation of highly organized amyloid fibrils is associated with a wide range of conformational pathologies, including primarily neurodegenerative diseases. Such disorders are characterized by misfolded proteins that lose their normal physiological roles and acquire toxicity. Recent findings suggest that proteostasis network impairment may be one of the causes leading to the accumulation and spread of amyloids. These observations are certainly contributing to a new focus in anti‐amyloid drug design, whose efforts are so far being centered on single‐target approaches aimed at inhibiting amyloid aggregation. Chaperones, known to maintain proteostasis, hence represent interesting targets for the development of novel therapeutics owing to their potential protective role against protein misfolding diseases. In this minireview, research on nanoparticles that can either emulate or help molecular chaperones in recognizing and/or correcting protein misfolding is discussed. The nascent concept of “nanochaperone” may indeed set future directions towards the development of cost‐effective, disease‐modifying drugs to treat several currently fatal disorders. 相似文献
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Gregory B. Kharas Emi Hanawa Benjamin L. Hill Katherine Flynn Amy N. Addante Julio C. Argueta 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(3):197-201
Novel copolymers of trisubstituted ethylene monomers, alkyl ring-substituted 2-phenyl-1,1-dicyanoethylenes, RC6H4CH = C(CN)2 (where R is 2-methyl, 3-methyl, 4-methyl, 4-ethyl, 4-i-propyl, 4-butyl, 4-i-butyl, and 4-t-butyl) and 4-fluorostyrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR. The order of relative reactivity (1/r 1) for the monomers is 4-ethyl (42.6) > 4-butyl (29.4) > 4-t-butyl (26.7) > 4-i-butyl (1.6) > 4-i-propyl (1.29) > 3-methyl (1.26) > 2-methyl (0.8) > 4-methyl (0.4). High T g of the copolymers, in comparison with that of poly(4-fluorostyrene) indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. Decomposition of the copolymers in nitrogen occurred in two steps, first in 183–500°C range with residue (5–30% wt.), which then decomposed in the 500–800°C range. 相似文献
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Dr. Rebeca Arevalo Dr. Ramón López Prof. Larry R. Falvello Dr. Lucía Riera Dr. Julio Perez 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(1):379-389
The reactions of [Re(N-N)(CO)3(PMe3)]OTf (N-N=2,2′-bipyridine, bipy; 1,10-phenanthroline, phen) compounds with tBuLi and with LiHBEt3 have been explored. Addition to the N-N chelate took place with different site-selectivity depending on both chelate and nucleophile. Thus, with tBuLi, an unprecedented addition to C5 of bipy, a regiochemistry not accessible for free bipy, was obtained, whereas coordinated phen underwent tBuLi addition to C2 and C4. Remarkably, when LiHBEt3 reacted with [Re(bipy)(CO)3(PMe3)]OTf, hydride addition to the 4 and 6 positions of bipy triggered an intermolecular cyclodimerization of two dearomatized pyridyl rings. In contrast, hydride addition to the phen analog resulted in partial reduction of one pyridine ring. The resulting neutral ReI products showed a varied reactivity with HOTf and with MeOTf to yield cationic complexes. These strategies rendered access to ReI complexes containing bipy- and phen-derived chelates with several C(sp3) centers. 相似文献
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The microwave spectrum has been investigated for the molecule of Benzenesulphonyl chloride within the 8–18 Ghz frequency region. Several a and b type bands corresponding to the Cl35 and Cl37 Isotopes were observed and assigned. We have also used the CNDO/2 method in order to estimate some molecular parameters and the dipole moment. The theoretical calculation and the experimental data have been joined to derive a reliable structure of the molecule concluding that the Cl is located on the plane of the benzene ring. 相似文献
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