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111.
112.
A straightforward 2-step parallel synthesis for structurally diversified spiro compounds is developed. 2-Bromobenzoic acids are used as common building blocks to couple with a series of conjugated enoles or enamines. Sequential intramolecular free radical Michael additions lead to formation of spirobenzolactones, spirobenzolactams, spirobenzolactone-lactams, spiorbenzolactone-thiolactones, spiordilactones, and bridged-spirolactones. 相似文献
113.
Yi DK Selvan ST Lee SS Papaefthymiou GC Kundaliya D Ying JY 《Journal of the American Chemical Society》2005,127(14):4990-4991
Quantum dots (QDs) and magnetic nanoparticles (MPs) are of interest for biological imaging, drug targeting, and bioconjugation because of their unique optoelectronic and magnetic properties, respectively. To provide for water solubility and biocompatibility, QDs and MPs were encapsulated within a silica shell using a reverse microemulsion synthesis. The resulting SiO2/MP-QD nanocomposite particles present a unique combination of magnetic and optical properties. Their nonporous silica shell allows them to be surface modified for bioconjugation in various biomedical applications. 相似文献
114.
Georgia Tsolomiti 《Tetrahedron letters》2004,45(51):9353-9355
The unexpected synthesis of N-substituted 2-acetoxy-5-arylpyrroles, from the reaction of 3-aroyl-propionamides with a large excess of refluxing acetyl chloride, and their alkaline hydrolysis to 3- and 4-pyrrolin-2-ones, is described. 相似文献
115.
116.
Development of an Electrochemical Biosensor for the Rapid Detection of Cholera Toxin Based on Air Stable Lipid Films with Incorporated Ganglioside GM1 Using Graphene Electrodes
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Stephanos Karapetis Georgia‐Paraskevi Nikoleli Christina G. Siontorou Dimitrios P. Nikolelis Nikolaos Tzamtzis Nikolas Psaroudakis 《Electroanalysis》2016,28(7):1584-1590
The present work describes a miniaturized potentiometric cholera toxin sensor on graphene nanosheets with incorporated lipid films. Ganglioside GM1, the natural cholera toxin receptor, immobilized on the stabilized lipid films, provided adequate selectivity for detection over a wide range of toxin concentrations, fast response time of ca. 5 min, and detection limit of 1 nM. The proposed sensor is easy to construct and exhibits good reproducibility, reusability, selectivity, long shelf life and high sensitivity of ca. 60 mV/decade of toxin concentration. The method was implemented and validated in lake water samples. This novel ultrathin film technology is currently adapted to the rapid detection of other toxins that could be used in bioterrorism. 相似文献
117.
Phase-sensitive nuclear Overhauser enhancement spectroscopy (NOESY) experiments, (3)J couplings and computational molecular modeling (MM2* and MMFF force fields) were employed to examine the conformational properties of verrucarin A in chloroform solutions. The MMFF force field calculations resulted in a family of 12 low-energy structures along with their populations, the latter being determined by the NMR analysis of molecular flexibility in solution(NAMFIS) deconvolution analysis. The concluded model was capable of reproducing successfully the experimental NOESY cross-peak volumes and the proton-coupling constants. Among the 12 conformers, the one which was similar to the structure of verrucarin A in the solid state was the predominant accounting for 75% of the total relative population, although other low-energy conformations contributed to a lesser degree in order to explain the experimental data. 相似文献
118.
Sheridan RP McGaughey GB Cornell WD 《Journal of computer-aided molecular design》2008,22(3-4):257-265
As an extension to a previous published study (McGaughey et al., J Chem Inf Model 47:1504–1519, 2007) comparing 2D and 3D
similarity methods to docking, we apply a subset of those virtual screening methods (TOPOSIM, SQW, ROCS-color, and Glide)
to a set of protein/ligand pairs where the protein is the target for docking and the cocrystallized ligand is the target for
the similarity methods. Each protein is represented by a maximum of five crystal structures. We search a diverse subset of
the MDDR as well as a diverse small subset of the MCIDB, Merck’s proprietary database. It is seen that the relative effectiveness
of virtual screening methods, as measured by the enrichment factor, is highly dependent on the particular crystal structure
or ligand, and on the database being searched. 2D similarity methods appear very good for the MDDR, but poor for the MCIDB.
However, ROCS-color (a 3D similarity method) does well for both databases.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
119.
Iliana Papamichael Georgia Chatziparaskeva Jose Navarro Pedreño Irene Voukkali María Belén Almendro Candel Antonis A. Zorpas 《Current Opinion in Green and Sustainable Chemistry》2022
Energy, food, and clothing are the three main components of humanity. Each one individually and all together contribute to climate change and CO2 emissions, to the consumption of natural resources, as well as influencing social attitude and behaviour. The global trends of the fashion industry are projected to expand in value from $1.5 trillion in 2020 to about $2.25 trillion by 2025, presenting that the fashion request is on continual growth. As natural resources (e.g., water) to produce clothes and shoes are limited nowadays, more resource-efficient production pathways must be identified; moreover, natural materials must replace plastic fibres, natural colours must replace synthetic ones, and ‘buy-and throw-way philosophy’ must turn into ‘buy-less-and-these-are-needed’ as so to reduce the environmental footprint of the fashion sector. This work emphasized the necessity of developing a new business circular model for the fashion industry with the potential of providing plethora of economic opportunities in the framework of waste management. Clear vision and new strategy development in the fashion sector is proposed, including the involvement of customers, businesses and policy makers, driven by the promotion of circular economy through knowledge exchange, education as well as regulatory relief measures for a synergic transition towards the circularity of the fashion industry. 相似文献
120.
Efthimia I. Alevizou Georgia D. Pappa Epaminondas C. Voutsas 《Fluid Phase Equilibria》2009,284(2):99-105
The UNIFAC model is extended to mixtures of ionic liquids consisting of the imidazolium cation and the hexafluorophosphate anion with alkanes, cycloalkanes, alcohols and water. Two new main groups, the imidazolium and the hexafluorophosphate groups, are introduced in UNIFAC. The required group interaction parameters between these groups and the existing UNIFAC main groups, CH2, OH and H2O, are determined by fitting binary liquid–liquid equilibrium and infinite dilution activity coefficient experimental data. The predictive capability of the extended UNIFAC model is examined against experimental data for vapour–liquid equilibrium, liquid–liquid equilibrium and activity coefficients at infinite dilution of binary and ternary systems containing 1-alkyl-3-alkyl′-imidazolium hexafluorophosphate ionic liquids, alkanes, cycloalkanes, alcohols and water. The results indicate that UNIFAC is a reliable model for phase equilibrium predictions in mixtures containing this type of ionic liquids. 相似文献