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161.
Mina Saeedi Shirin Ansari Mohammad Mahdavi Reyhaneh Sabourian Tahmineh Akbarzadeh Alireza Foroumadi 《合成通讯》2013,43(20):2311-2318
A novel series of 1,2,3-triazole-dihydro[3,2-c]chromenone derivatives were synthesized through an efficient three-step reaction starting from 4-hydroxybenzaldehyde. All the newly synthesized compounds were characterized by infrared and NMR spectroscopy as well as elemental analysis and evaluated for their acetylcholinesterase inhibitory activity. 相似文献
162.
Dr. Riccardo Amorati Dr. Luca Valgimigli Dr. Peter Dinér Dr. Khadijeh Bakhtiari Dr. Mina Saeedi Prof. Lars Engman 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(23):7510-7522
Hydroxyaryl alkyl tellurides are effective antioxidants both in organic solution and aqueous biphasic systems. They react by an unconventional mechanism with ROO. radicals with rate constants as high as 107 M ?1 s?1 at 303 K, outperforming common phenols. The reactions proceed by oxygen atom transfer to tellurium followed by hydrogen atom transfer to the resulting RO. radical from the phenolic OH. The reaction rates do not reflect the electronic properties of the ring substituents and, because the reactions occur in a solvent cage, quenching is more efficient when the OH and TeR groups have an ortho arrangement. In the presence of thiols, hydroxyaryl alkyl tellurides act as catalytic antioxidants towards both hydroperoxides (mimicking the glutathione peroxidases) and peroxyl radicals. The high efficiency of the quenching of the peroxyl radicals and hydroperoxides could be advantageous under normal cellular conditions, but pro‐oxidative (thiol depletion) when thiol concentrations are low. 相似文献
163.
Masoud Salavati-Niasari Mina Gholami-Daghian Mahdiyeh Esmaeili-Zare Fatemeh Sadat Sangsefidi 《Journal of Cluster Science》2013,24(4):1093-1101
A novel and simple one-step solid state reaction in the presence of a suitable surfactant, sodium dodecyl sulfate (SDS), and a novel precursor, [bis(acetylacetonato)zinc(II)]; [Zn(acac)2]; has been developed to synthesize uniform zinc oxide microflakes with an average thickness of 0.3–2.4 μm. In the absence of SDS the product samples contained microrods. The formation of zinc oxide microflakes depends on the molar ratio of Zn(II)/SDS and the experimental procedure. The products were characterized by X-ray diffraction, photoluminescence spectroscopy, FT-IR spectroscopy, surface area, scanning electron microscopy and transmission electron microscopy to depict the phase and morphology. The synthesized ZnO microflakes have a hexagonal zincite structure. 相似文献
164.
The present paper reports a comprehensive and complementary study on structural, electronic and phonon properties of face centered cubic fluorites, namely CaF2, BaF2 and SrF2, using first principles density functional calculations within the generalized gradient approximation. The calculated lattice constants and bulk modulus are in good agreement with available experimental data. The analysis of band structure and density of states confirms the ionic character for all the three fluorides. The phonon dispersion curves and corresponding phonon density of states obtained in the present work are consistent with the available experimental and other theoretical data. The LO-TO splitting is maximum for CaF2, which confirms that the ionicity is maximum in the case of CaF2. The phonon properties for SrF2 have been calculated for the first time. 相似文献
165.
A technique is developed and luminescence quenching of complexes immobilized on cation-exchange membranes is considered. The
mechanism of the luminescence quenching of the complexes by molecular oxygen is discussed. 相似文献
166.
Suzuki–Miyaura cross-coupling reactions in water using in situ generated palladium(II)–phosphazane complexes 总被引:1,自引:1,他引:0
Mojtaba Amini Abbas Tarassoli Saeed Yousefi Sepideh Delsouz-Hafshejani Mina Bigdeli Mahnaz Salehifar 《中国化学快报》2014,25(1):166-168
The phosphazane derivatives(L1–3) were readily obtained by reaction of different ratios of PCl3 and PhNH2. The L1–3 derivatives were found to be efficient ligands in the palladium-catalyzed Suzuki C–C coupling reactions in water. It was determined that with the use of L1–3 /Pd(OAc)2 system as a catalyst, aryl halides undergo Suzuki cross-couplings with arylboronic acids to give the desired products in moderate to excellent yields. 相似文献
167.
Samira Rahmani-Nezhad Leila Khosravani Mina Saeedi Kouros Divsalar Loghman Firoozpour Yaghoub Pourshojaei 《合成通讯》2013,43(6):741-749
A series of coumarin–resveratrol hybrids, 3-arylcoumarin derivatives 3a–u, were synthesized through the intermolecular condensation reaction of various salicylaldehydes and phenylacetic acids in the presence of 1,4-diazabicyclo[2.2.2]octane under solvent-free conditions. All the synthesized compounds were screened for their inhibitory potency against soybean 15-lipoxygenase. Among them, three compounds (3c, 3j, and 3q) showed good enzyme-inhibitory activities. 相似文献
168.
Mohammad Mahdavi Ramin Najafi Mina Saeedi Eskandar Alipour Abbas Shafiee Alireza Foroumadi 《Helvetica chimica acta》2013,96(3):419-423
Various isoindolo[2,1‐a]quinazoline‐5,11‐dione derivatives 3 were synthesized in good yields by means of the reductive reaction of N‐substituted 2‐nitrobenzamides 1 and 2‐formylbenzoic acids 2 in the presence of SnCl2?2 H2O under reflux in EtOH (Scheme, Table). The procedure needed two steps, the reduction of the nitro group of the 2‐nitrobenzamide and ring closure by nucleophilic addition of the NH2 group to both the formyl and carboxylic acid C?O groups. 相似文献
169.
An efficient and convenient method for the synthesis of 1,4-dihydropyridines from β-dicarbonyl compounds, aldehydes, and ammonium acetate and the synthesis of fused 1,4-dihydropyridines from dimedone in the presence of Preyssler heteropolyacid catalyst are reported under reflux conditions with good to excellent yields. Preyssler heteropolyacid catalyst is easily prepared, stable (up to 300 °C), reusable, efficient, green and inexpensive. 相似文献
170.
The mechanism and dynamical properties for the reaction of NCS and OH radicals have been investigated theoretically. The minimum energy paths (MEP) of the reaction were calculated using the density functional theory(DFT) at the B3LYP/6-311 G^** level, and the energies along the MEP were further refined at the QCISD(T)/6-311 G^** level. As a result, the reaction mechanism of the title reaction involves three channels, producing HCS NO and HNC SO products, respectively. Path Ⅰ and path Ⅱ are competitive, with some advantages for path Ⅰ in kinetics. As for path Ⅲ, it looks difficult to react for its high energy barrier. Moreover, the rate constant have been calculated over the temperature range of 8190-2500K using canonical variational transition-state theory (CVT). It was found that the rate constants for both path Ⅰ and path Ⅱ are negatively dependent on temperature, which is similarwith the experimental results for reactions of NCS with NO and NO2, and the variational effect for the rate constant calculation olavs an important role in whole temperature range. 相似文献