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991.
Amir Koolivand Alireza Badiei Pezhman Arab Ghodsi Mohammadi Ziarani 《Journal of the Iranian Chemical Society》2016,13(7):1315-1324
A nanoporous carbon (CMK-3) was synthesized and used to adsorb 2-phenylethanol (PEA) from aqueous solutions. The characterization of CMK-3 by N2 adsorption isotherm revealed the formation of a nanoporous carbon with average pore diameter and surface area of 3.34 nm and 1268 m2 g?1, respectively. Column-like particle morphology of CMK-3 was observed from scanning electron microscope images. To evaluate the feasibility of CMK-3 as a potential PEA adsorbent, batch adsorption experiments were conducted for aqueous PEA solutions. The results showed that CMK-3 is an efficient sorbent for the separation of PEA from water. The optimized adsorbent doses were found to be 0.3 and 2.2 g L?1 for 30 and 300 mg L?1 PEA, respectively. Our studies about the effect of pH on CMK-3 adsorption capacity revealed that the adsorption capacity increased at lower pH due to the protonation of PEA. Three adsorption models, Langmuir, Freundlich and Temkin were used to describe the adsorption isotherms. Thermodynamic parameters such as ΔG 0, ΔH 0, and ΔS were also evaluated, and it was found that the sorption process was spontaneous, endothermic, and physical in nature. The adsorption kinetics was investigated in detail and the pseudo-second-order kinetic equation fitted the experimental data very well. The mechanistic study by Weber-Morris model revealed that the overall adsorption process was simultaneously governed by external mass transfer and intraparticle diffusion. Almost all (97 %) adsorbed PEA was successfully recovered into ethanol which is a common solvent in fragrance industry. CMK-3 was proved to be a promising adsorbent for the adsorption-recovery of PEA from aqueous solution. 相似文献
992.
Alireza Zarrinjahan Majid Moghadam Valiollah Mirkhani Shahram Tangestaninejad Iraj Mohammadpoor-Baltork 《Journal of the Iranian Chemical Society》2016,13(8):1509-1516
Efficient epoxidation of alkenes catalyzed by tetrakis(p-aminophenyl)porphyrinatomanganese(III) chloride, [Mn(TNH2PP)Cl], supported on graphene oxide nanosheets, is reported. The catalyst, [Mn(TNH2PP)Cl]@GO, was prepared by covalent attachment of amino groups of porphyrin to carboxylic acid groups of GO. This new heterogenized catalyst was characterized by ICP, FT-IR and diffuse reflectance UV–vis spectroscopies, scanning electron microscopy and transmission electron microscopy. This catalyst was applied as an efficient and reusable catalyst in the epoxidation of alkenes with NaIO4 at room temperature, in the presence of imidazole as axial ligand. The most noteworthy advantage of [Mn(TNH2PP)Cl]@GO is its high reusability in the oxidation reactions, in which the catalyst was reused several times without significant loss of its catalytic activity. 相似文献
993.
This paper examines theoretically a novel mechanism of generating negative (pulling) radiation force for acoustic manipulation of spherical carriers equipped with piezoelectric actuators in its inner surface. In this mechanism, the spherical particle is handled by common plane progressive monochromatic acoustic waves instead of zero-/higher- order Bessel beams or standing waves field. The handling strategy is based on applying a spatially uniform harmonic electrical voltage at the piezoelectric actuator with the same frequency of handling acoustic waves, in order to change the radiation force effect from repulsive (away from source) to attractive (toward source). This study may be considered as a start point for development of contact-free precise handling and entrapment technology of active carriers which are essential in many engineering and medicine applications. 相似文献
994.
Alireza Salimi Beni Maryam Zarandi 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(2):374-382
Density functional theory (DFT) and MP2 calculations have been employed to study of 3-amino-4-nitrofurazan molecule using the standard 6-311++G(d,p) basis set. The chemical properties of the 3-amino-4-nitrofurazan have been extensively studied. The geometries of molecules in the gas phase were optimized and compared with the crystallography of this substance. The results suggest that A form is the most stable form in the gas phase and it is the predominant tautomer in solution according to the DFT and MP2 calculations, respectively. In addition, variation of dipole moments in the gas phase, the specific solvent effects with addition of one molecule of water near the electrophilic centers of tautomers, the transition state of proton transfer assisted by a water molecule, the NBO charges of atoms and the potential energy surface were investigated. The calculated highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) are presented. 相似文献
995.
Alireza Salimi Beni Masumeh Aazari Alireza Najafi Chermahini Maryam Zarandi 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(9):1859-1868
Density functional theory and MP2 methods have been employed to study of proton transfer reaction in annular tautomerization of tetrahydroimidazo[4,5-d]imidazole-2,5(1H,3H)-dione (glycoluril). Ten different tautomers are possible for the tetrahydroimidazo[4,5-d]imidazole-2,5(1H,3H)-dione. For all molecules, the Gibbs free energy at 0 and 298 K was estimated. In addition variation of dipole moments and charges on atoms are studied in the gas phase and solution, the specific solvent effects with addition of one molecule of water near the electrophilic centers of tautomer and the NBO charges of atoms were investigated. NBO analysis shows that there is a strong interaction between nitrogen lone pairs and double bonds. 相似文献
996.
Miri Alireza Tavasoli Ahmad Sovizi Mohammad Reza 《Journal of Thermal Analysis and Calorimetry》2022,147(1):263-273
Journal of Thermal Analysis and Calorimetry - In this work, lithium titanate oxide (Li4Ti5O12) (LTO) and praseodymium ion doped in lithium titanate oxide (Pr-LTO) were synthesized in a... 相似文献
997.
Dr. Ayan Dasgupta Yara van Ingen Michael G. Guerzoni Dr. Kaveh Farshadfar Prof. Jeremy M. Rawson Dr. Emma Richards Prof. Alireza Ariafard Prof. Rebecca L. Melen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(45):e202201422
An efficient and mild reaction protocol for the decarbonylation of isocyanates has been developed using catalytic amounts of Lewis acidic boranes. The electronic nature (electron withdrawing, electron neutral, and electron donating) and the position of the substituents (ortho/meta/para) bound to isocyanate controls the chain length and composition of the products formed in the reaction. Detailed DFT studies were undertaken to account for the formation of the mono/di-carboxamidation products and benzoxazolone compounds. 相似文献
998.
Naseri Amene Asghari Sarabi Ghazale Samadi Morasae Yousefi Mahdieh Ebrahimi Mahdi Moshfegh Alireza Z. 《Research on Chemical Intermediates》2022,48(3):911-933
Research on Chemical Intermediates - Photocatalytic wastewater treatment and concurrent energy production or metal ions conversion to less harmful products have great potential to address both... 相似文献
999.
Moghadaseh Yahyapour Mehdi Ranjbar Alireza Mohadesi Moslem Rejaeinegad 《Electroanalysis》2022,34(6):1012-1020
In this study we report the Zn/La3+ metal organic frameworks (MOFs) were synthesized with the co-precipitation assisted microwave method. Zn/La3+ MOFs were used as a new nanocomposite for the design and construction of a nanosensor based on glassy carbon electrode (GCE). MOFs due to their unique and excellent physicochemical properties can be used in sensors based on glassy carbon electrode (GCE). The synergistic effect of MOFs on glassy carbon electrode increases the power of the limits of detection (LOD). In this study, a new chemical sensor was fabricated by electro polymerization to measure buprenorphine with MOFs based on molecularly imprinted polymer. Zn/La3+ MOFs nanostructures were identified with scanning electron microscopy (SEM), Dynamic light scattering (DLS), Transmission electron microscopy (TEM) and the Fourier-transform infrared spectroscopy (FT-IR) spectra. Buprenorphine was used as a template, pyrrole was used as a monomer, potassium ferrocyanide as an electrochemical active tracer in electropolymerization processes and the parameters affecting the sensor response were optimized. At the Zn/La3+ MOF/MIP electrode, the calibration curve in the linear region was obtained in the concentration range between 4 to 50 ng/ml and the detection limit was 1.08 ng/ml. In a new strategy, Zn/La3+ MOFs nanostructures can be introduced as new materials with high efficiency which used at chemical sensors for detection of the opiates in all over the world. 相似文献
1000.
Sara Tavakkoli Fard Dr. Kohei Sekine Dr. Kaveh Farshadfar Dr. Frank Rominger Dr. Matthias Rudolph Dr. Alireza Ariafard Prof. Dr. A. Stephen K. Hashmi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(10):3552-3559
A simple gold-catalyzed annulation of 1,8-dialkynylnaphthalenes utilizing a cationic gold catalyst was developed. Such a peri-position of two alkynyl substituents has not been studied in gold catalysis before. Dependent on the substrate, the reactions either follow a mechanism involving vinyl cation intermediates or involve a dual gold catalysis mechanism which in an initial 6-endo-dig-cyclization generates gold(I) vinylidene intermediates that are able to insert into C−H bonds. Indenophenalene derivatives were obtained in moderate to high yields. In addition, the bidirectional gold-catalyzed annulation of tetraynes provided even larger conjugated π-systems. The optoelectronic properties of the products were also investigated. 相似文献