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71.
Ali Ramazani Amir Tofangchi Mahyari Morteza Rouhani Aram Rezaei 《Tetrahedron letters》2009,50(40):5625-5627
Reaction of an isocyanide with an iminium ion intermediate, formed by reaction between an electron-poor 2-hydroxybenzaldehyde derivative and a secondary amine in the presence of silica gel proceeds smoothly at room temperature to afford benzo[b]furan derivatives in high yields. 相似文献
72.
Cu2S nanoparticles were electrosynthesized by cyclic voltammetry between 0.10 and 1.50 V in the presence of polyvinylalcohol as stabilizer. The structure and nature of the resulting Cu2S poly (vinyl alcohol) composite were characterized by transmission electron microscopy and X-ray diffraction. The results show that electrochemically synthesized Cu2S nanoparticles are homogeneously dispersed and well separated from one another with a mean diameter of about 12 nm. 相似文献
73.
In any finite group G, the commutativity degree of G (denoted by d(G)) is the probability that two randomly chosen elements of G commute. More generally, for every n ≥ 2 the nth commutativity degree (denoted by d
n
(G)) is the probability that a randomly chosen ordered (n + 1)-tuple of the group elements is mutually commuting. The aim of this paper is to generalize the definition of d(G) and d
n
(G) to every compact group G (infinite and even uncountable). We shall state some results concerning compact groups and we will extend some results in
Erfanian et al. (Comm. Algebra 35 (2007), 4183–4197) and Lescot (J. Algebra 177 (1995), 847–869). 相似文献
74.
Ali Ramazani Yavar Ahmadi Asemeh Mashhadi Malekzadeh Aram Rezaei 《Heteroatom Chemistry》2011,22(6):692-698
Reactions of (N‐isocyanimino) triphenylphosphorane with 2‐oxopropylbenzoate (or acetate) in the presence of aromatic carboxylic acids and primary amines proceed smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4‐oxadiazole derivatives in high yields. The reaction proceeds smoothly and cleanly under mild conditions, and no side reactions were observed. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:692–698, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20735 相似文献
75.
Reza Rezaei Darestani Philip Winter Elena N. Kitova Jack A. Tuszynski John S. Klassen 《Journal of the American Society for Mass Spectrometry》2016,27(5):876-885
Tubulin, which is the building block of microtubules, plays an important role in cell division. This critical role makes tubulin an attractive target for the development of chemotherapeutic drugs to treat cancer. Currently, there is no general binding assay for tubulin–drug interactions. The present work describes the application of the catch-and-release electrospray ionization mass spectrometry (CaR-ESI-MS) assay to investigate the binding of colchicinoid drugs to αβ-tubulin dimers extracted from porcine brain. Proof-of-concept experiments using positive (ligands with known affinities) and negative (non-binders) controls were performed to establish the reliability of the assay. The assay was then used to screen a library of seven colchicinoid analogues to test their binding to tubulin and to rank their affinities. 相似文献
76.
Ali Ramazani Nadia Fattahi Mona Ashtari Aram Rezaei 《Phosphorus, sulfur, and silicon and the related elements》2016,191(6):908-912
Reaction of N-isocyaniminotriphenylphosphorane (Ph3PNNC) with an aromatic aldehyde in the presence of ferrocene carboxylic acid and a secondary amine proceeds smoothly at room temperature under neutral conditions to afford sterically congested ferrocene-containing 1,3,4-oxadiazole derivatives in high yields. The reaction progresses smoothly and clearly under mild conditions and no side reactions were observed. 相似文献
77.
We study the expansion method for the gluon distribution function at low x values and calculate the charm structure functions in the LO and NLO analysis. Our results provide a compact formula for the ratio R c = F L c /F 2 c , which is approximately independent of x and the details of the parton distribution function at low x values. This ratio could be a good probe of the charm structure function F 2 c in the proton deduced from the reduced charm cross sections at DESY HERA. These results show that the charm structure functions obtained are in agreement with HERA experimental data and other theoretical models. 相似文献
78.
Hassan Rezaei Satish D. Kulkarni Praveen G. Saptarshi 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(8):1332-1339
Discharge of heavy metals from metal processing industries is known to have adverse effects on the environment. Biosorption of heavy metals by metabolically inactive biomass of microbial organisms is an innovative and alternative technology for removal of these pollutants from aqueous solution. Presence of heavy metals in the aquatic system is posing serious problems. Zinc has been used in many industries and removal of Zn ions from waste water is significant. Biosorption is one of the economic methods used for removal of heavy metals. In the present study, the biomass obtained from the dried Chlorella pyrenoidosa was used for evaluating the biosorption characteristics of Zn ions in aqueous solutions. Batch adsorption experiments were performed with this material and it was found that the amount of metal ions adsorbed increased with the increase in the initial metal ion concentration. In this study effect of agitation time, initial metal ion concentration, temperature, pH and biomass dosage were studied. Maximum metal uptake (q max) observed at pH 5 was 101.11 mg/g. The biosorption followed both Langmuir and Freundlich isotherm model. The adsorption equilibrium was reached in about 1 h. The kinetic of biosorption followed the second-border rate. The biomass could be regenerated using 0.1 M HNO3. A positive value of ΔH° indicated the endothermic nature of the process. A negative value of the free energy (ΔG°) indicated the spontaneous nature of the adsorption process. A positive value of ΔS° showed increased randomness at solid-liquid interface during the adsorption of heavy metals, it also suggests some structural changes in the adsorbate and the adsorbent. FTIR Spectrums of Chlorella pyrenoidosa revealed the presence of hydroxyl, amino, carboxylic and carbonyl groups. The scanning electron micrograph clearly revealed the surface texture and morphology of the biosorbent. 相似文献
79.
80.