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371.
Derek M. Peloquin Askhat N. Bimukhanov Anuar A. Aldongarov Jon W. Merkert Bernadette T. Donovan-Merkert Thomas A. Schmedake 《Molecules (Basel, Switzerland)》2022,27(23)
Complexes consisting of earth-abundant main group metals such as silicon with polypyridine ligands are of interest for a variety of optical and electronic applications including as electrochromic colorants. Previous spectroelectrochemical studies with tris(2,2′-bipyridyl)silicon(IV) hexafluorophosphate, [Si(bpy)3](PF6)4, demonstrated an ability to control the color saturation of the potential electrochromic dye, with the intensity of the dye’s green color increasing as the charge state sequentially reduces from 4+ to 1+. In this study, the synthesis of bis(4′-(4-tolyl)-2,2′:6′,2″-terpyridine)silicon(IV) hexafluorophosphate, [Si(ttpy)2](PF6)4, is reported along with electrochemical and spectroelectrochemical analyses. Computational modeling (density functional theory) is used to further elucidate the electrochromic properties of previously reported Si(bpy)3n+ species and the new Si(ttpy)2n+ species. While the homoleptic tris(bidentate)silicon(IV) complexes are attractive as electrochromic dyes for tunable color saturation, the bis(tridentate)silicon(IV) complexes are attractive as polychromatic electrochromic dyes. 相似文献
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373.
This review discusses the latest advances in electrodeposition of nanostructured catalysts for electrochemical energy conversion: fuel cells, water splitting, and carbon dioxide electroreduction. The method excels at preparing efficient and durable nanostructured materials, such as nanoparticles, single atom clusters, hierarchical bifunctional combinations of hydroxides, selenides, phosphides, and so on. Yet, in most cases, chemical composition cannot be decoupled from catalyst morphology. This compromises the rational design of electrodeposition procedures because performance indicators depend on both morphology and surface chemistry. We expect electrodeposition will keep unraveling its potential as the preferred method for electrocatalyst synthesis once a deeper understanding of the electrochemical growth process is combined with complex chemistries to have control of the morphology and the surface composition of complex (bifunctional) electrocatalysts. 相似文献
374.
Jon Babi Linglan Zhu Angela Lin Azalea Uva Hana El-Haddad Atang Peloewetse Helen Tran 《Journal of polymer science. Part A, Polymer chemistry》2021,59(21):2378-2404
Sequence-defined polymers can be programmed to self-assemble into precise nanostructures for applications in biosensing, drug delivery, optics, and molecular computation. Inspired by the natural self-assembly processes present in biological protein and DNA systems, sets of molecular design rules have emerged across materials classes as instructions to build a variety of tunable structures. This review highlights recent advances in self-assembled sequence-defined and sequence-specific polymers across peptides, peptoids, DNA, and non-biological synthetic materials, with a focus on synthesis, assembly processes and overall structure. Specifically, these self-assembled structures are free-floating, as such constructs can potentially serve as a platform for the aforementioned applications. Emphasis is placed on the molecular design of polymers that self-assemble into zero-dimensional, one-dimensional, two-dimensional, or three-dimensional nanostructures. With the development of automated syntheses and increasing control over self-assembly, future work may focus on emerging classes of compatible hybrid materials with exciting directions toward new architectures and applications. 相似文献
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The relative reaction rates of several silatranes (derivatives of 2,8.9-trioxa-5-aza- 1-silatricyclo[3.3.3.01,5]undecane) and HgCl2 in acetone-d6to yield the corresponding organomercury compound are of the order of e.g., 5 × 10?1 1 mol?1 sec?1 or slightly less, a rate that is unexpectedly high compared to the essentially inert parent organotrialkoxysilanes. Thus, the apical Si&.zsbnd;C bond of the silatrane is extraordinarily susceptible to direct electrophilic attack by mercury(II). The rates decrease in the order CH2CH, C6H5, p-ClC6H4 > CH3 > CH3CH2, CH3CH2CH2 > C6H11, ClCH2, Cl2CH, CH3CH2O. The effects of varying the solvent and the counterions are noted, and the probable mechanism is discussed. 相似文献
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379.
Ian D TomlinsonJohn Mason Jon N BurtonRandy Blakely Sandra J Rosenthal 《Tetrahedron》2003,59(40):8035-8047
There is a growing demand for compounds with very high affinities for the dopamine transporter protein (DAT) that can be conjugated to fluorescent markers such as cadmium selenide/zinc sulfide core/shell nanocrystals. This paper describes the design and synthesis of two derivatives of the DAT antagonists GBR 12935 and GBR 12909. These compounds have a high biological affinity for DAT and may be conjugated to nanocrystals via a thiol linkage without a significant reduction in their biological activity. Such conjugates may be used in fluorescent imaging studies. 相似文献
380.
This paper describes the construction of an expert system to help the admissions tutor for a university degree in business and management which receives some 2000 applications for entry each year, using the SAGE shell. What originally began as a ‘demonstrator project’ is shown to be of practical value, in terms of both producing a usable expert system and clarifying and questioning the selection criteria used by the admissions tutor. A particular conclusion emerging from this work which may be relevant to many expert systems applications is that ethical and practical considerations dictated that some questions involving judgement could not be delegated by the admissions tutor to the clerical staff. It thus became necessary to develop two versions of the expert system, one a full ‘admissions-tutor system’, the other a more limited version for day-to-day use. 相似文献