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941.
Yue Shi Donna J. Menzies Kelly M. Tsang Mark P. Del Borgo Christopher D. Easton Marie‐Isabel Aguilar Patrick Perlmutter Vinh X. Truong John S. Forsythe 《Journal of polymer science. Part A, Polymer chemistry》2017,55(15):2527-2536
In this work, we demonstrate the potential of surface‐initiated single electron transfer living radical polymerization for surface modification applications that confer low‐fouling properties. The versatility of the technique, which can be applied to a wide variety of substrates, has been displayed by the successful grafting of a range of monomers after immobilizing a bromine initiator on the surface via plasma polymerization. The thickness of the grafted surfaces can be controlled through variation of reaction parameters such as monomer concentration, reaction time, and the ratio between catalyst and ligand. Furthermore, the low‐fouling properties of the resulting surfaces were demonstrated against fully concentrated serum proteins and adhesive fibroblast cells, via grafting of N‐hydroxyethyl acrylamide (N‐HEA) or [2‐(methacryloyloxy)ethyl]dimethyl‐(3‐sulfopropyl) ammonium hydroxide (SBMA). This rapid and versatile coating technique, which has the ability to be applied to a wide range of substrates, can be performed in aqueous conditions without the exclusion of atmospheric oxygen, and shows excellent potential for the surface modification of biomaterial surfaces that require low‐fouling properties. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2527–2536 相似文献
942.
Petit-Domínguez María Dolores Quintana Carmen Vázquez Luis del Pozo María Cuadrado Isabel Parra-Alfambra Ana María Casero Elena 《Mikrochimica acta》2018,185(7):1-8
Microchimica Acta - A multistep paper-based analytical device (mPAD) was designed and applied to the voltammetric determination of total inorganic arsenic. The electrodeposition of gold... 相似文献
943.
Dr. Sara Morales-Reina Dr. Chandan Giri Maxime Leclercq Dr. Sonia Vela-Gallego Isabel de la Torre Dr. José R. Castón Dr. Mathieu Surin Dr. Andrés de la Escosura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(5):1082-1090
One of the major goals in systems chemistry is to create molecular assemblies with emergent properties that are characteristic of life. An interesting approach toward this goal is based on merging different biological building blocks into synthetic systems with properties arising from the combination of their molecular components. The covalent linkage of nucleic acids (or their constituents: nucleotides, nucleosides and nucleobases) with lipids in the same hybrid molecule leads, for example, to the so-called nucleolipids. Herein, we describe nucleolipids with a very short sequence of two nucleobases per lipid, which, in combination with hydrophobic effects promoted by the lipophilic chain, allow control of the self-assembly of lipidic amphiphiles to be achieved. The present work describes a spectroscopic and microscopy study of the structural features and dynamic self-assembly of dinucleolipids that contain adenine or thymine moieties, either pure or in mixtures. This approach leads to different self-assembled nanostructures, which include spherical, rectangular and fibrillar assemblies, as a function of the sequence of nucleobases and chiral effects of the nucleolipids involved. We also show evidence that the resulting architectures can encapsulate hydrophobic molecules, revealing their potential as drug delivery vehicles or as compartments to host interesting chemistries in their interior. 相似文献
944.
Dr. Khaleel I. Assaf Dr. Josef Holub Dr. Eduard Bernhardt Dr. Josep M. Oliva-Enrich Dr. M. Isabel Fernández Pérez Prof. Dr. Moisés Canle Dr. J. Arturo Santaballa Dr. Jindřich Fanfrlík Dr. Drahomír Hnyk Prof. Dr. Werner M. Nau 《Chemphyschem》2020,21(10):971-976
The supramolecular recognition of closo,closo-[B21H18]− by cyclodextrins (CDs) has been studied in aqueous solution by isothermal titration calorimetry and nuclear magnetic resonance spectroscopy. These solution studies follow up on previous mass-spectrometric measurements and computations, which indicated the formation and stability of CD ⋅ B21H18− complexes in the gas phase. The thermodynamic signature of solution-phase binding is exceptional, the association constant for the γ-CD complex with B21H18− reaches 1.8×106 M−1, which is on the same order of magnitude as the so far highest observed value for the complex between γ-CD and a metallacarborane. The nature of the intermolecular interaction is also examined by quantum-mechanical computational protocols. These suggest that the desolvation penalty, which is particularly low for the B21H18− anion, is the decisive factor for its high binding strength. The results further suggest that the elliptical macropolyhedral boron hydride is another example of a CD binder, whose extraordinary binding affinity is driven by the chaotropic effect, which describes the intrinsic affinity of large polarizable and weakly solvated chaotropic anions to hydrophobic cavities and surfaces in aqueous solution. 相似文献
945.
Katarzyna Rajkowska Anna Kozirg Anna Otlewska Magorzata Piotrowska Elena Atrin-Blasco Isabel Franco-Castillo Scott G. Mitchell 《Molecules (Basel, Switzerland)》2020,25(23)
Moulds inhabiting mineral-based materials may cause their biodeterioration, contributing to inestimable losses, especially in the case of cultural heritage objects and architectures. Fungi in mouldy buildings may also pose a threat to human health and constitute the main etiological factor in building related illnesses. In this context, research into novel compounds with antifungal activity is of high importance. The aim of this study was to evaluate the antifungal activity of polyoxometalate-ionic liquids (POM-ILs) and their use in the eradication of moulds from historical brick. In the disc diffusion assay, all the tested POM-ILs inhibited growth of a mixed culture of moulds including Engyodontium album, Cladosporium cladosporioides, Alternaria alternata and Aspergillus fumigatus. These were isolated from the surfaces of historical brick barracks at the Auschwitz II-Birkenau State Museum in Oświęcim, Poland. POM-IL coatings on historical brick samples, under model conditions, showed that two compounds demonstrated very high antifungal activity, completely limiting mould growth and development. The antifungal activity of the POM-ILs appeared to stem from their toxic effects on conidia, as evidenced by environmental scanning transmission electron microscopy observations. The results herein indicated that POM-ILs are promising disinfectant materials for use not only on historical objects, but probably also on other mineral-based materials. 相似文献
946.
Paula G. Saiz Naroa Iglesias Bárbara González Navarrete Maibelin Rosales Yurieth Marcela Quintero Ander Reizabal Dr. Joseba Orive Dr. Arkaitz Fidalgo Marijuan Dr. Edurne S. Larrea Dr. Ana Catarina Lopes Prof. Luis Lezama Dr. Andreina García Prof. Senentxu Lanceros-Mendez Prof. María Isabel Arriortua Dr. Roberto Fernández de Luis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(61):13861-13872
947.
Ellen Y. Cotrina Dr. Ana Gimeno Dr. Jordi Llop Prof. Dr. Jesús Jiménez-Barbero Dr. Jordi Quintana Dr. Rafel Prohens Dr. Isabel Cardoso Dr. Gemma Arsequell 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(72):17462-17469
The protein transthyretin (TTR) modulates amyloid-β (Aβ) peptides deposition and processing and this physiological effect is further enhanced by treatment with iododiflunisal (IDIF), a small-molecule compound (SMC) with TTR tetramer stabilization properties, which behaves as chaperone of the complex. This knowledge has prompted us to design and optimize a rapid and simple high-throughput assay that relies on the ability of test compounds to form ternary soluble complexes TTR/Aβ/SMC that prevent Aβ aggregation. The method uses the shorter Aβ(12–28) sequence which is cheaper and simpler to use while retaining the aggregation properties of their parents Aβ(1–40) and Aβ(1–42). The test is carried out in 96-plate wells that are UV monitored for turbidity during 6 h. Given its reproducibility, we propose that this test can be a powerful tool for efficient screening of SMCs that act as chaperones of the TTR/Aβ interaction that may led to potential AD therapies. 相似文献
948.
Buey RM Barasoain I Jackson E Meyer A Giannakakou P Paterson I Mooberry S Andreu JM Díaz JF 《Chemistry & biology》2005,12(12):1269-1279
The interactions of microtubules with most compounds described as stabilizing agents have been studied. Several of them (lonafarnib, dicumarol, lutein, and jatrophane polyesters) did not show any stabilizing effect on microtubules. Taccalonolides A and E show paclitaxel-like effects in cells, but they were not able to modulate in vitro tubulin assembly or to bind microtubules, which suggests that other factors are involved in their cellular effects. The binding constants of epothilones, eleutherobin, discodermolide, sarcodictyins, 3,17beta-diacetoxy-2-ethoxy-6-oxo-B-homo-estra-1,3,5(10)-triene, and dictyostatin to the paclitaxel site; the critical concentrations of ligand-induced assembly; and their cytotoxicity in carcinoma cells have been measured, and correlations between these parameters have been determined. The inhibition of cell proliferation correlates better with the binding enthalpy change than with the binding constants, suggesting that large, favorable enthalpic contribution to the binding is desired to design paclitaxel site drugs with higher cytotoxicity. 相似文献
949.
Adrenoceptors are members of the important G protein coupled receptor family for which the detailed mechanism of activation
remains unclear. In this study, we have combined docking and molecular dynamics simulations to model the ligand induced effect
on an homology derived human α1A adrenoceptor. Analysis of agonist/α1A adrenoceptor complex interactions focused on the role of the charged amine group, the aromatic ring, the N-methyl group of adrenaline, the beta hydroxyl group and the catechol meta and para hydroxyl groups of the catecholamines. The most critical interactions for the binding of the agonists are consistent with
many earlier reports and our study suggests new residues possibly involved in the agonist-binding site, namely Thr-174 and
Cys-176. We further observe a number of structural changes that occur upon agonist binding including a movement of TM-V away
from TM-III and a change in the interactions of Asp-123 of the conserved DRY motif. This may cause Arg-124 to move out of
the TM helical bundle and change the orientation of residues in IC-II and IC-III, allowing for increased affinity of coupling
to the G-protein. 相似文献
950.
Carreño MC García I Ribagorda M Merino E Pieraccini S Spada GP 《Organic letters》2005,7(14):2869-2872
[reaction: see text] Photoswitchable enantiopure sulfinyl azo compounds have been synthesized. A remarkable perturbation of the azo system by the stereogenic sulfinyl moiety has been observed by CD in both the trans and the cis azobenzenes resulting by photoisomerization. After five irradiation cycles, the configurational integrity of these chiral switches remains unchanged. 相似文献