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51.
研究了二元叠加码Mq(t,k,d)也是一个二元等重码,给出了它成为最佳等重码的条件,研究了它的检错性. 相似文献
52.
Esmail Mohamadian Samin Hamidi Fleming Martínez 《Physics and Chemistry of Liquids》2017,55(6):805-816
Experimental solubility of deferiprone (DFP) in N-methyl-2-pyrrolidone (NMP) + ethanol (EtOH) mixtures at 293.2, 298.2, 303.2 and 308.2 K was determined and mathematically represented using various models. The trained versions of the van’t Hoff equation, its combined version with log-linear model, Jouyban–Acree model and a combination of van’t Hoff + Jouyban–Acree model were reported to simulate DFP solubility in the binary mixture compositions at various temperatures. The mean percentage deviation (MPD) was used as an accuracy criterion. The obtained overall MPDs for back-calculated and predicted solubility of DFP in NMP + EtOH mixtures varied from 1.1% to 3.2% and 2.6% to 6.6%, respectively. Some of apparent thermodynamic quantities for the dissolution processes of DFP are also reported. 相似文献
53.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(45):14263-14267
The increasing popularity of biomimetic design principles in nanomedicine has led to therapeutic platforms with enhanced performance and biocompatibility. This includes the use of naturally derived cell membranes, which can bestow nanocarriers with cell‐specific functionalities. Herein, we report on a strategy enabling efficient encapsulation of drugs via remote loading into membrane vesicles derived from red blood cells. This is accomplished by supplementing the membrane with additional cholesterol, stabilizing the nanostructure and facilitating the retention of a pH gradient. We demonstrate the loading of two model drugs: the chemotherapeutic doxorubicin and the antibiotic vancomycin. The therapeutic implications of these natural, remote‐loaded nanoformulations are studied both in vitro and in vivo using animal disease models. Ultimately, this approach could be used to design new biomimetic nanoformulations with higher efficacy and improved safety profiles. 相似文献
54.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(47):15099-15103
The regioselective conversion of C−H bonds into C−Si bonds is extremely important owing to the natural abundance and non‐toxicity of silicon. Classical silylation reactions often suffer from poor functional group compatibility, low atom economy, and insufficient regioselectivity. Herein, we disclose a template‐assisted method for the regioselective para silylation of toluene derivatives. A new template was designed, and the origin of selectivity was analyzed experimentally and computationally. An interesting substrate–solvent hydrogen‐bonding interaction was observed. Kinetic, spectroscopic, and computational studies shed light on the reaction mechanism. The synthetic significance of this strategy was highlighted by the generation of a precursor of a potential lipophilic bioisostere of γ‐aminobutyric acid (GABA), various late‐stage diversifications, and by mimicking enzymatic transformations. 相似文献
55.
56.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(52):16777-16781
A mild, oxidant‐free, and selective Cp*CoIII‐catalyzed amidation of thioamides with robust dioxazolone amidating agents via C(sp3)−H bond activation to generate the desired amidated products is reported. The method is efficient and allows for the C−H amidation of a wide range of functionalized thioamides with aryl‐, heteroaryl‐, and alkyl‐substituted dioxazolones under the Cp*CoIII‐catalyzed conditions. The observed regioselectivity towards primary C(sp3)−H activation is supported by computational studies and the cyclometalation is proposed to proceed by means of an external carboxylate‐assisted concerted metalation/deprotonation mechanism. The reported method is a rare example of the use of a directing group other than the commonly used pyridine and quinolone classes for Cp*CoIII‐catalyzed C(sp3)−H functionalization and the first to exploit thioamides. 相似文献
57.
Prof. Dr. So Won Youn Tae Yun Ko Young Ho Jang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(23):6736-6740
A Pd-catalyzed intermolecular oxidative annulation between N-Ts-anilines and styrenes was developed. This method offers a straightforward and robust approach to a wide range of 3-arylindoles using readily available starting materials with good functional-group tolerance and high regioselectivity and efficiency. Further elaboration of the products obtained from this process provided access to highly functionalized and structurally diverse indoles, for example, 3-(indol-3-yl)carbazoles, 1,9-dihydropyrrolo-[2,3-b]carbazoles, and 3′-aryl-3,5′-biindoles. 相似文献
58.
Manuel van Gemmeren Marino Börjesson Andreu Tortajada Shang-Zheng Sun Keisho Okura Prof. Ruben Martin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(23):6658-6662
A switchable site-selective catalytic carboxylation of allylic alcohols has been developed in which CO2 is used with dual roles, both facilitating C−OH cleavage and as a C1 source. This protocol is characterized by its mild reaction conditions, absence of stoichiometric amounts of organometallic reagents, broad scope, and exquisite regiodivergency which can be modulated by the type of ligand employed. 相似文献
59.
Two new hybrid compounds, [Cu(1)(phen)(H2O)][Cu(2)(phen)(H2O)]([Cu(3)]0.25(H2O)][P2Mo5O23]·3.75H2O (1) and [Cu(en)2]1.5[P2Mo5O23]2·(enH2)3·2H2O (2) (phen = 1,10-phenanthroline, en = ethylenediamine), have been hydrothermally synthesized and characterized by IR, UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), powder XRD analyses, TG analyses, cyclic voltammogram analyses, elemental analyses, and single crystal X-ray diffraction analyses. Single crystal X-ray diffraction analyses reveal that the two compounds have a 1-D chain structure formed by Strandberg-type POMs and TMCs with –A–B–C–B–A–B–C–B– linking mode, then further extend into a 2-D layer structure through π?π or hydrogen bond interactions. 相似文献
60.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(41):12777-12781
Films of mesoscopic domains self‐assembled from fluorocarbon/hydrocarbon diblock copolymers (FnHm ) at the air/water interface were found to display highly elastic behavior. We determined the interfacial viscoelasticity of domain‐patterned FnHm Langmuir monolayers by applying periodic shear stresses. Remarkably, we found the formation of two‐dimensional gels even at zero surface pressure. These monolayers are predominantly elastic, which is unprecedented for surfactants, exhibiting gelation only at high surface pressures. Systematic variation of the hydrocarbon (n =8; m =14, 16, 18, 20) and fluorocarbon (n =8, 10, 12; m =16) block lengths demonstrated that subtle changes in the block length ratio significantly alter the mechanics of two‐dimensional gels across one order of magnitude. These findings open perspectives for the fabrication of two‐dimensional gels with tuneable viscoelasticity via self‐assembly of mesoscale, low‐molecular‐weight materials. 相似文献