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991.
Yanping He Yunyan Kuang Fener Chen Suxi Wang Lei Ji Erik De Clercq Jan Balzarini Christophe Pannecouque 《Monatshefte für Chemie / Chemical Monthly》2005,136(7):1233-1245
Summary. A series of 6-naphthylmethyl substituted HEPT analogues bearing a β-carbonyl and a terminal phenyl ring or ester groups on the N-1 side chain of uracil were synthesized, and the in vitro anti-HIV activity was evaluated. Most of these HEPTs were considerably less potent and selective or inactive, only a few compounds showed moderate or high activity against HIV-1. The results demonstrated that the anti-HIV-1 activity of 6-naphthylmethyl substituted HEPT analogues was diminished or eliminated when the β-oxygen of N-1 side chain was replaced by a carbonyl group. 相似文献
992.
Thermally activated delayed fluorescence molecules (TADF) molecules have been found to undergo efficient intersystem crossing (ISC) and reverse intersystem crossing (RISC) processes, which benefit their successful applications in organic light emitting diodes (OLEDs). Due to their long-lived delayed fluorescence, TADF molecules can also be applied in time-resolved luminescence imaging. Besides their special singlet properties, their excited triplet characteristics provide their potential applications in triplet-triplet annihilation upconversion (TTA-UC), photodynamic therapy (PDT) and organic photocatalytic synthesis by used as a triplet photosensitizer. 相似文献
993.
For ease of detection, soluble forms of phage-displayed scFv antibodies are usually expressed with a tag, e.g., c-myc or His
(Histidine). The binding is then assayed by a monoclonal antibody to the tag. In this article, we describe the use of biotinylated
antigen for detecting soluble scFv antibodies without utilizing the peptide tag detection system. The scFv antibodies were
against the oncoplacental antigen heat-stable alkaline phosphatase (HSAP). The method essentially consisted of either reverse
Western or antigen capture enzyme-linked immunosorbent assay (ELISA). In the reverse Western, periplasmic extract was electrophoresed,
and binding to biotinylated antigen was detected by the detection system based on streptavidin-horseradish peroxidase. The
antigen capture ELISA utilized the binding of periplasmic extract to a polystyrene plate. We have also demonstrated the use
of antigen capture ELISA for studying specificity and affinity of the selected clones. Although these techniques have been
developed for antibodies to HSAP, they have general utility for phage expression systems without a peptide tag. 相似文献
994.
Moran Paul D. Bartlett John R. Bowmaker Graham A. Woolfrey James L. Cooney Ralph P. 《Journal of Sol-Gel Science and Technology》1999,15(3):251-262
Titania sols, gels and nanopowders have been produced by the controlled hydrolysis of tetraisopropyltitanate (TPT) in sodium bis(2-ethylhexyl)sulfosuccinate (AOT) reverse micelles. Particle formation and aggregation have been investigated by photon correlation spectroscopy, the crystal phases by FT-Raman spectroscopy, and the crystallite dimensions of the precipitates by transmission electron microscopy. Nanoparticles could be produced at relatively high Ti(IV) concentrations (up to 0.05 mol dm–3). These nanoparticles aggregated into sols, with colloid sizes of 20–300 nm, eventually forming gelatinous precipitates. The kinetics of particle formation and aggregation were controlled by varying the primary process parameters [TPT], [H2O]/[AOT] (w0), and [H2O]/[Ti(IV)] (R), yielding a range of products including stable, transparent sols, precipitates and monolithic gels. The aggregation kinetics and physical properties of the sols depended strongly on w0. Different titania phases were produced, depending on w0; w0 6 yielded amorphous particles, while w0 10 produced anatase. The dimensions of the crystallites were comparable to those of the parent reverse micelles. A model was developed to interpret the effect of the primary process parameters on colloidal stability: (1) nucleation to form primary crystallites occurs by rapid hydrolysis and condensation reactions within the reverse micelle and (2) subsequent colloidal growth by aggregation occurs by reverse micellar exchange, where the rate of growth is governed by electrostatic and steric stability factors which increase as [AOT]/[TPT] (S) and residual [H2O]/[AOT] (wr) increase. 相似文献
995.
XU Yechun SHEN Jianhua LUO Xiaomin SHEN Xu CHEN Kaixian & JIANG Hualiang Center for Drug Discovery Design State Key Laboratory of New Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences ChineseAcademy of Sciences Shanghai China 《中国科学B辑(英文版)》2004,47(5):355-366
Molecular recognition and specific protein-ligandinteractions are central to many biochemical processes,such as enzyme catalysis, assembly of organelles, en-ergy transduction, signaling, diverse control functions,and replication, expression and storage of the geneticmaterial[1]. Moreover, protein-ligand interactions pro-vide the mechanism of many drug therapies and un-derstanding of such interactions is thus significant forrational drug design[1,2]. For the experimental studiesof protein-ligan… 相似文献
996.
TiO2 nanoparticles were prepared using the hydrolysis of titanium tetraisopropoxide (TTIP) in W/O microemulsions consisting of
water, nonionic surfactant and cyclohexane. The photocatalytic degradation of p-nitrophenol has been studied by using a batch reactor in the presence of UV light. The crystallite size and crystallinity
increase with a decrease of hydrophilic group chain length and an increase of calcinations temperature. In addition, the photocatalytic
activity increases with an increase of hydrophilic group length.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
997.
998.
999.
The enzymes catalase (bovine liver, EC 1.11.1.6) and -penicillinase (bacillus cereus strain 569, type I, EC 3.5.2.6) were successfully encapsulated in the polyacrylamide matrix. The encapsulation was carried out in the water pool of water/aerosol OT/n-hexane reverse micelles. The polymeric particles of encapsulated enzymes were reasonably monodisperse and had diameters in the range of several tens of nanometers as measured from quasi-elastic laser light scattering. The activity- pH profile of the encapsulated enzymes in buffer followed the same pattern as that of free enzymes. However, the encapsulated enzymes were found to be less active than their free forms. The enzymes in the encapsulated form were more stable (both thermal stability and shelf-life) as compared to free enzymes. The activity of the encapsulated enzymes was found to be dependent on the degree of cross-linking of the polymer matrix. The greater the cross-linking in the matrix, the lesser were the activity of the encapsulated enzyme. 相似文献
1000.
The geometries of 7-azaindole (7AI), its tautomer (7AT), and 7AI–H2O and 7AT–H2O complexes were optimised in the ground state and some low-lying singlet excited states using the 3-21G basis set. Differences of total energies of the optimised ground and excited states and the vertical excitation energies of these systems were used to explain the observed electronic spectra. Effect of solvation of these systems in bulk water was studied using the polarized continuum model (PCM). The mode of binding of a water molecule in the S2(n–π*) excited state of 7AI was found to be quite different from those in its ground and π–π* excited states. It is shown that crossing of the lowest two singlet excited-state potential surfaces S1(π–π*) and S2(n–π*) of 7AI occurs in the vapour phase under geometry relaxation while on interaction with water, the S2(n–π*) excited state is raised up appreciably going even above the S3(π–π*) excited state. Ground- and excited-state molecular electrostatic potential mapping was carried out, which led to valuable information regarding the nature of excited states of the above-mentioned systems. 相似文献