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91.
Saleh Shahin Pirouzfar Vahid Alihosseini Afshar 《Journal of Thermal Analysis and Calorimetry》2019,136(4):1817-1830
Journal of Thermal Analysis and Calorimetry - In this study, a refrigeration cycle was simulated with different refrigerants in a petrochemical plant in Iran. Using Aspen HYSYS Software, necessary... 相似文献
92.
Firouzeh Nemati Ali Ghorbani Gharjeh Ghiyaei Behrouz Notash Mojtaba Hajiloo Shayegan Vahid Amani 《Tetrahedron letters》2014
An efficient route for the synthesis of gem-bis(dithiocarbamate) derivatives is developed using dithiocarbamic acid salts generated from primary aliphatic amines and CS2. The method offers high yields, employs mild reaction conditions, and demonstrates excellent functional group compatibility. The structures of the products were confirmed spectroscopically and by X-ray analysis. 相似文献
93.
Asad Asadujjaman Vahid Ahmadi Antoine Michel Claude Franc Annabelle Bertin 《Journal of polymer science. Part A, Polymer chemistry》2019,57(19):2064-2073
A novel copolymer based on supramolecular motif 2,6‐diaminopyridine and water‐soluble acrylamide, poly[N‐(6‐acetamidopyridin‐2‐yl) acrylamide‐co‐acrylamide], was synthesized via reversible addition–fragmentation chain transfer (RAFT) polymerization with various monomer compositions. The thermoresponsive behavior of the copolymers was studied by turbidimetry and dynamic light scattering (DLS). The obtained copolymers showed an upper critical solution temperature (UCST)‐type phase transition behavior in water and electrolyte solution. The phase transition temperature was found to increase with decreasing amount of acrylamide in the copolymer and increasing concentration of the solution. Furthermore, the phase transition temperature varied in aqueous solutions of electrolytes according to the nature and concentration of the electrolyte in accordance with the Hoffmeister series. A dramatic solvent isotope effect on the transition temperature was observed in this study, as the transition temperature was almost 10–12 °C higher in D2O than in H2O at the same concentration and acrylamide composition. The size of the aggregates below the transition temperature was larger in D2O compared to that in H2O that can be explained by deuterium isotope effect. The thermoresponsive behavior of the copolymers was also investigated in different cell medium and found to be exhibited UCST‐type phase transition behavior in different cell medium. Such behavior of the copolymers can be useful in many applications including biomedical, microfluidics, optical materials, and in drug delivery. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2064–2073 相似文献
94.
Arabali Vahid Karimi-Maleh Hassan Beitollahi Hadi Moradi Reza Ebrahimi Mahmoud Ahmar Hamid 《Ionics》2015,21(4):1153-1161
Ionics - In this study, a carbon paste electrode (CPE) was chemically modified with Pt/carbon nanotubes (CNTs) nanocomposite and 8,9-dihydroxy-7-methyl-12H-benzothiazolo [2,3-b] quinazolin-12-one... 相似文献
95.
96.
We investigate the coupling of a single molecule to a single spherical gold nanoparticle acting as a nanoantenna. Using scanning probe technology, we position the particle in front of the molecule with nanometer accuracy and measure a strong enhancement of more than 20 times in the fluorescence intensity simultaneous to a 20-fold shortening of the excited state lifetime. Comparisons with three-dimensional calculations guide us to decipher the contributions of the excitation enhancement, spontaneous emission modification, and quenching. Furthermore, we provide direct evidence for the role of the particle plasmon resonance in the molecular excitation and emission processes. 相似文献
97.
Mathematical Notes - Let $$\mathcal{A}$$ be a prime $$\ast$$ -algebra. In this paper, assuming that $$\Phi:\mathcal{A}\to\mathcal{A}$$ satisfies $$\Phi(A\diamond B \diamond C)=\Phi(A)\diamond B... 相似文献
98.
Zahra Khubi-Arani Mehdi Salami-Kalajahi Mohammad Najafi Hossein Roghani-Mamaqani Vahid Haddadi-Asl Seyed Mehdi Ghafelebashi-Zarand 《Polymer Science Series B》2010,52(3-4):184-192
In the present study, based on a complete mechanism, a Monte Carlo simulation method is employed to investigate the kinetics of styrene free radical polymerization over bi-functional initiators in a bulk medium. The effects of the concentration of initiator and the monomer, of the temperature on monomer conversion, average molecular weights, polydispersity index, and molecular weight distribution are inspected and compared with mono-functional initiators. According to the simulation results, an increase in either the concentration of initiator or the temperature leads to the rise of the monomer conversion and to the reduction of the average molecular weights, while the increase of the monomer concentration results in the rise of both monomer conversion and molecular weights, which is in accord with predictions of the theory of free-radical polymerization. In addition, application of bi-functional initiators increases both monomer conversion and average molecular weight and results in narrower chain length distributions. 相似文献
99.
Beigi-Somar Vahid Homami Seyed Saied Ghazanfarpour-Darjani Majid Monzavi Amirhossein 《Monatshefte für Chemie / Chemical Monthly》2020,151(2):231-241
Monatshefte für Chemie - Chemical Monthly - A domino catalytic reaction between terminal alkynes, isocyanates, and malonates has been developed. Copper acetylides attack on isocyanates to form... 相似文献
100.
Shayan Maryam Pirouzfar Vahid Sakhaeinia Hossein 《Journal of Thermal Analysis and Calorimetry》2020,139(4):2399-2411
Journal of Thermal Analysis and Calorimetry - One of the most important environmental issues in the oil, gas, and petrochemical industries is the appropriate disposal of waste hydrocarbon gases in... 相似文献