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61.
Asif Nisar Muhammad Saeed Muhammad Usman Majid Muneer Muhammad Adeel Iltaf Khan Javaid Akhtar 《国际化学动力学杂志》2020,52(10):645-654
Photodegradation of organic pollutants strongly depends on design of metal oxide semiconductor photocatalysts. Graphene, if composited with ZnO, can effectively enhance its photocatalytic performance for the eradication of pollutants from aqueous medium. Here in, ZnO-rGO is reported as highly active catalyst for degradation of methylene blue. A 200-mg/L solution of methylene blue dye was completely degraded within 1 h in comparison to 74% and 56% degradation over ZnO and rGO, respectively. The commonly used mechanisms of heterogeneous catalytic reactions, the Langmuir-Hinshelwood mechanism, and the Eley-Rideal mechanisms, were used to describe the reaction kinetics. The Langmuir-Hinshelwood mechanism was found as more favorable in this study. Apparent activation energy, Eap, true activation energy, ET, entropy, ΔS, and enthalpy, ΔH were calculated as 36.2 kJ/mol, 13.1 kJ/mol, 197.5 J/mol, and 23.1 kJ/mol, respectively. 相似文献
62.
Niloufar Afzali Reihaneh Kardanpour Farnaz Zadehahmadi Shahram Tangestaninejad Majid Moghadam Valiollah Mirkhani Adam Mechler Iraj Mohammadpoor‐Baltork Mehrnaz Bahadori 《应用有机金属化学》2019,33(11)
A novel heterogeneous nanocatalyst was established by supporting molybdenum (VI) on Zr6 nodes in the structure of the well‐known UiO‐66 metal–organic framework (MOF). The structure of the UiO‐66 before and after Mo (VI) immobilization was confirmed with XRD, DR‐FTIR and UV–vis spectroscopy, and the presence and amount of Mo (VI) was identified by X‐ray photoelectron spectroscopy and inductively coupled plasma atomic emission spectroscopy. TEM imaging confirmed the absence of Mo clusters on the MOF surface, while SEM confirmed that the appearance of the MOF has not changed upon immobilizing the Mo (VI) catalyst. BET adsorption measurements were used to confirm the porosity of the catalyst. The catalytic activity of this heterogeneous catalyst was investigated in oxidation of sulfides with H2O2 in acetonitrile and oxidative desulfurization of dibenzothiophene. Easy work up, convenient and steady reuse and high activity and selectivity are prominent properties of this new hybrid material. 相似文献
63.
64.
Sahra Balilehvand Seyed Majid Hashemianzadeh SeyedehSaleheh Razavi Hedayat Karimi 《Adsorption》2012,18(1):13-22
A combination of ab initio quantum mechanical (QM) calculations and canonical Monte Carlo (CMC) simulations are employed to
investigate possible usage of single-walled silicon nanotubes (SWSiNTs) as a novel media for hydrogen and methane adsorption
as well as their separation from each other. By fitting the force field, a Morse potential model is selected as an efficient
potential to describe the binding energies between both hydrogen-SiNTs and methane-SiNTs obtained from ab initio calculations.
Then CMC simulations are performed to evaluate the adsorption and separation behaviors of H2 and CH4 on the three different sizes of SiNTs including (5, 5), (7, 7), and (9, 9) SiNTs at ambient temperatures and pressures from
1 up to 10 MPa. As a comparison, the adsorption and separation of H2 and CH4 on the (8, 8) CNTs which are isodiameter with (5, 5) SiNTs are also simulated. Results are indicative of remarkable enhancement
of H2 and CH4 adsorption capacity on the SiNTs compared to the CNTs, which arise from stronger van der Waals (VDW) attractions. In the
case of methane adsorption on SiNTs, the stored volumetric energy exceeds the goal of the US Freedom CAR Partnership by 2010,
which can not be achieved by methane compression at such low pressures. Moreover, simulation results indicate that SiNTs preferentially
adsorb methane relative to hydrogen in their equimolar mixture, which results in efficient separation of these gases from
each other at 293 K. 相似文献
65.
Majid M. Heravi Navabeh Nami Hossien A. Oskooie Rahim Hekmatshoar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1873-1878
The addition of dialkyl acetylenedicarboxylate to o-phenylenediamine, o-aminophenol, and o-aminothiophenol under microwave irradiation in solventless system rapidly afforded quinoxaline, benzoxazine, and benzothiazine derivatives, respectively. 相似文献
66.
Rahim Hekmat Shoar Majid M. Heravi Leila Pedram Shadi Hasan Raeiat Zeinab Jaddi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2563-2567
A facile and rapid synthesis of thio compounds, analogues to ciprofloxacin, and norfloxacin is described. 相似文献
67.
Majid M. Heravi Neda Zamani Ahari Hossein A. Oskooie Mitra Ghassemzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1701-1712
Abstract Mild and efficient S-methylation of thiols and o-methylation of phenols and naphthols occurs with dimethyl sulfate (DMS) supported on basic alumina under microwave irradiation in solventless system. 相似文献
68.
Masoud Nasr-Esfahani Majid Moghadam Iraj Mohammadpoor-Baltork Mohammad Hasan Boostanifar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):2004-2009
A series of thioamides are transformed to their corresponding oxo analogues in good to excellent yields with acidified, wet, silica-supported tetrabutylammonium periodate under solvent-free conditions. 相似文献
69.
Hamid Reza Shaterian Asghar Hosseinian Majid Ghashang Fahimeh Khorami Neda Karimpoor 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2333-2338
An environmentally friendly procedure for the preparation of dihydropyrimidinone derivatives or their sulfur analogues under thermal solvent-free conditions in the presence of aluminium hydrogen sulfate [Al(HSO4)3] and alumina sulfuric acid (Al2O3-SO3H) as heterogeneous catalysts was developed. 相似文献
70.