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201.
In this work the Hawking-Unruh effect on the quantum entanglement of bosonic field in background of a spherically symmetric black hole of Gauss-Bonnet gravity is investigated beyond the single mode approximation. The entanglement decreases due to Hawking-Unruh effect. However, it has been shown that the dimensions of space time, Gauss-Bonnet term and the parameter β of initial entangled state would be influenced on this degradation. In our investigation, we consider the accelerated observer either near or far from the event horizon and inspect entanglement degradation for them. The mutual information of this bosonic system is also calculated in beyond the single mode approximation and we show that the mutual information will have different behavior when the Hawking temperature increases. 相似文献
202.
Mehrorang Ghaedi Javad Tashkhourian Morteza Montazerozohori Mustafa Soylak 《International journal of environmental analytical chemistry》2013,93(4):386-400
The efficiencies and performances of silver nanoparticle loaded activated carbon modified with 2-(4-isopropylbenzylideneamino)thiophenol (IPBATP-Ag-NP-AC) and activated carbon modified with IPBATP (IPBATP-AC), as new sorbents, were evaluated for separation and preconcentration of Cu2+, Zn2+, Co2+, Cd2+ and Pb2+ ions from real environmental samples. The retained metals content was reversibly eluted using 5?mL of CH3COOH (6.0?mol?L?1) and/or 10?mL of 4.0?mol?L?1 HNO3 for IPBATP-Ag-NP-AC and IPBATP-AC, respectively. The experimental parameters influence the recoveries of metal ions including pH, amounts of ligand and supports, condition of eluents, sample and eluent flow rates of has been investigated. The preconcentration factors were found to be 100 for Zn2+, Cd2+, Co2+, Cu2+ and 50 for Pb2+ ions using IPBATP-Ag-NP-AC, and 50 for Zn2+, Cd2+, Co2+, Cu2+ and 25 for Pb2+ ions using IPBATP-AC. The detection limit of both SPE-based sorbents was between 1.6–2.5?ng?mL?1 for IPBATP-AC and 1.3–2.5?ng?mL?1 for IPBATP-Ag-NP-AC. The proposed methods have been successfully applied for the extraction and determination of the understudy metal ions content in some real samples with extraction efficiencies higher than 90% and relative standard deviations (RSD) lower than 2.4%. 相似文献
203.
204.
Mohammad Ali Zolfigol Peyman Salehi Morteza Shiri 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2273-2277
H 3 PMo 12 O 40 · xH 2 O was found to be an effective catalyst for the preparation of bis-indolyl derivatives from indole and aromatic, aliphatic, heterocyclic aldehydes or ketones in ethanol at room temperature. 相似文献
205.
The reaction mechanism of C2H2 and N2O on the singlet potential energy surface is investigated in this study, at the B3LYP/6-311++G(3df,3pd), MP2/6-311++G(d,p), and CCSD(T) levels of theory. We have obtained three kinds of products in both methods, B3LYP and MP2, which have enough thermodynamic stability. The results reveal that the product P1, CH2CO + N2, is spontaneous and exothermic with ?86.176 and ?83.149 kcal/mol in Gibbs free energy and enthalpy of reaction at the MP2 level, respectively. Hence, the product P1 is thermodynamically the most favored adduct of the C2H2 + N2O gas phase reaction at atmospheric pressure and 298.15 K temperature. 相似文献
206.
Mohammad Fazavi Seyyed Mohsen Hosseini Morteza Nouri-Taleghani Mahmood Amani 《Journal of Dispersion Science and Technology》2014,35(6):882-888
Two-phase flow of liquids in pipelines is crucial subject in many industries such as chemical and petroleum. Accurate prediction of pressure gradient will lead to a better design of an energy efficient transportation system. Although numerous studies for prediction of two-phase flowing pressure drop have been reported in the literature, the accurate prediction of this parameter has been a topic of debate in many research areas. In this article, a novel model based on least square support vector (LSSVM) was proposed for calculation of two-phase flowing pressure drop in horizontal pipes. The inputs of this model are oil and water superficial velocities, pipe diameter, pipe roughness, and oil viscosity. To develop and test the model, more than 700 experimental dataset from open literature were utilized. The results of proposed model were compared against the well-known empirical correlations. Statistical error analysis showed that the LSSVM model outperforms existing predictive models. Finally, an outlier diagnosis was performed to detect the doubtful experimental. 相似文献
207.
Bararjanian M Balalaie S Rominger F Movassagh B Bijanzadeh HR 《Molecular diversity》2011,15(2):583-594
Efficient methods for stereoselective synthesis of polyfunctional (E)-enaminones and (Z)-dithiocarbamates via one-pot five- and six-component sequential Ugi/Nucleophilic addition reactions are described. High
yields and high bond forming efficiency, and simple operations are the advantages of this method. 相似文献
208.
Yazdaninia Anoosha Jafari Seyed Hassan Ehsani Morteza Khajavi Ramin Khonakdar Hossein Ali 《Journal of Thermal Analysis and Calorimetry》2020,139(1):279-292
Journal of Thermal Analysis and Calorimetry - The influence of blending ratio and trifluoropropyl polyhedral oligomeric silsesquioxane (POSS) on microstructure, melt and cold crystallization... 相似文献
209.
Properties of melt processed polyamide 66 (PA66)/multiwalled carbon nanotube composite were first characterized experimentally. The experimental results exhibited the formation of crystalline layer around the nanotubes and a considerable enhancement in mechanical properties by incorporation of multiwalled carbon nanotube up to 1 wt%. Mechanical properties were analyzed in terms of structural parameters using micromechanical models proposed in this study. It was suggested that the mechanical properties were greatly dominated by crystalline layer and nanotube length. It was also deduced that the melt mixing process caused a significant nanotube breakage restricting further enhancement of nanocomposite properties at higher nanotube contents. Surface modification of nanotube provided better polymer‐nanotube interaction; however, it increased the mechanical properties marginally. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
210.
The mechanism and thermodynamic of NH3 + O2 reaction on the singlet and triplet potential energy surfaces (PES), were carried out using the RMP2 and CCSD (T)//RMP2 theoretical approaches in connection with the 6-311++G(d, p) basis set. Three pre-reactive complexes, 1C1, 1C2, and 3C1 on the singlet and triplet PES were formed between ammonia and molecular oxygen. With variety of pre-reactive complexes, six types of products are obtained, of which two types are found to be thermodynamically stable. The mechanistic properties of all products channels are discussed. Results show that production of HONO + H2 and HN(OH)2 are the main reaction channels in thermodynamic viewpoint with the Gibbs free energy of ?G° = ?34.681 and ?27.153 kcal/mol, respectively. Rate constants of the title reaction over the temperature range of (200–1000 K) show kinetic products are different from thermodynamic products. 相似文献