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991.
The Ramanujan Journal - Recently, Andrews and Yee studied two-variable generalizations of two identities involving partition functions $$p_\omega (n)$$ and $$p_\nu (q)$$ introduced by Andrews,... 相似文献
992.
The azo dye ligand 4‐(5‐chloro‐2‐hydroxyphenylazo)‐N‐thiazol‐2‐ylbenzenesulfonamide (H2L) formed by the coupling reaction of sulfathiazole and p‐chlorophenol was synthesized and characterized using elemental analysis and Fourier transform infrared (FT‐IR) as well as UV–visible spectra. Nano‐sized divalent Cu, Co, Ni, Mn and Zn complexes of the synthesized azo dye ligand were prepared and investigated using various spectroscopic and analytical techniques. Elemental and thermal analyses indicated the formation of the Cu(II), Ni(II) and Mn(II) complexes in a molar ratio of 1:2 (L:M) while Co(II) and Zn(II) complexes exhibited a 1:1 (M:L) ratio. FT‐IR spectral studies confirmed the coordination of the ligand to the metal ions through the phenolic hydroxyl oxygen, azo nitrogen, sulfonamide oxygen and/or thiazole nitrogen. The geometric arrangements around the central metal ions were investigated applying UV–visible and electron spin resonance spectra, thermogravimetric analysis and molar conductance measurements. X‐ray diffraction patterns revealed crystalline nature of H2L and amorphous nature of all synthesized complexes. Transmission electron microscopy images confirmed nano‐sized particles and their homogeneous distribution over the complex surface. Antibacterial, antifungal and antitumour activities of the investigated complexes were screened compared with familiar standard drugs to confirm their potential therapeutic applications. The Cu(II) complex showed IC50 of 3.47 μg ml?1 (5.53 μM) against hepatocellular carcinoma cells, which means that it is a more potent anticancer drug compared with the standard cisplatin (IC50 = 3.67 μg ml?1 (12.23 μM)). Furthermore, the Co(II), Ni(II), Cu(II) and Zn(II) complexes displayed IC50 greater than that of an applied standard anticancer agent (5‐flurouracil) towards breast carcinoma cells. Hence, these complexes can be considered as promising anticancer drugs. The mode of binding of the complexes with salmon serum DNA was determined through electronic absorption titration and viscosity studies. 相似文献
993.
The Ramanujan Journal - By means of the Hermite-theta function, we study the spectral resolution of the cubic Casimir operator on a fundamental domain of the Jacobi group. 相似文献
994.
Elbouyahyaoui Lakhdar Heyouni Mohammed Tajaddini Azita Saberi-Movahed Farid 《Numerical Algorithms》2021,87(3):1257-1299
Numerical Algorithms - The problem of shifted linear systems is an important and challenging issue in a number of research applications. Krylov subspace methods are effective techniques for... 相似文献
995.
996.
Mohammed Rammane Said Mesmoudi Abdeljalil Tri Bouazza Braikat Noureddine Damil 《国际流体数值方法杂志》2020,92(5):422-435
In this paper, we propose for the first time to extend the application field of the high-order mesh-free approach to the stationary incompressible Navier-Stokes equations. This approach is based on a high-order algorithm, which combines a Taylor series expansion, a continuation technique, and a moving least squares (MLS) method. The Taylor series expansion permits to transform the nonlinear problem into a succession of continuous linear ones with the same tangent operator. The MLS method is used to transform the succession of continuous linear problems into discrete ones. The continuation technique allows to compute step-by-step the whole solution of the discrete problems. This mesh-free approach is tested on three examples: a flow around a cylindrical obstacle, a flow in a sudden expansion, and the standard benchmark lid-driven cavity flow. A comparison of the obtained results with those computed by the Newton-Raphson method with MLS, the high-order continuation with finite element method, and those of literature is presented. 相似文献
997.
Numerical Algorithms - In this paper, we present a family of Perry conjugate gradient methods for solving large-scale systems of monotone nonlinear equations. The methods are developed by combining... 相似文献
998.
Reham M. El‐Morshedy Mohammed M. El‐Gamil Mohamed Mahmoud Abou‐Elzahab Gaber M. Abu El‐Reash 《应用有机金属化学》2019,33(5)
The binuclear Cr (III), Mn (II) and Fe (III) complexes of N,N′‐(2,2′‐(2‐benzylmalonyl)bis (hydrazine‐1‐carbonothioyl))dibenzamide (H4BPCD), which derived from the combination of 2‐benzylmalonohydrazide suspension with benzoyl‐isothiocyanate, have been isolated and investigated by the necessary analytical and spectroscopic techniques. The IR studies show that H4BPCD dispose as a mono‐negative hexadentate ligand (NOS)2 towards Mn (II) ion and tetra‐negative hexadentate (NOS)2 towards both Cr (III) and Fe (III) ions. The values of molar conductance in DMSO suggested the non‐electrolytic nature for all complexes. The magnetic measurements and the electronic transitions data confirmed the hexa‐coordinate geometry of complexes. The DFT geometry optimization of all compounds and IR comparative study of both theoretical and experimental of H4BPCD were carried out. Moreover, the H4BPCD and its Cr (III) complex displayed intra ligand (π → π*) fluorescence emission spectra which corroborate their photoactive nature. The coordinated and crystalline water molecules have been investigated by (TG/DTG) studies. The kinetic and thermodynamic parameters were computed using Horowitz‐ Metzger, Coats‐Redfern and Broido methods. Biological studies of DNA binding, minimum inhibitory concentration, in vitro determination of SOD‐like activity and MTT‐cytotoxicity assay as well as molecular docking studies were tested for the ligand and its complexes. 相似文献
999.
Prof. Dr. Farid A. Badria Saleh Atef Prof. Dr. Abdullah Mohammed Al-Majid M. Ali Dr. Yaseen A. M. M. Elshaier Dr. Hazem A. Ghabbour Mohammad Shahidul Islam Dr. Assem Barakat 《ChemistryOpen》2019,8(10):1288-1297
The Michael addition reaction of barbituric acid with chalcones incorporating the indole scaffold was achieved by using a highly efficient bimetallic Iron–palladium catalyst in the presence of acetylacetone (acac). This catalytic approach produced the desired products in a simple operation and low catalyst loading with acceptable yield of the new hybrids. All tested compounds were subjected for biological activity on α-glucosidase and α-amylase. The results revealed that all synthesized compounds exhibited very good activity against both enzymes when compared to positive control (acarbose). Moreover, compound 5o showed the best activity whereas its IC50 (μM) are 13.02+0.01 and 21.71+0.82 for α-glucosidase and α-amylase respectively. Both compounds 5o and 5l exhibited high similarity in binding mode and pose with amylase protein (4UAC). The obtained data may be used for developing potential hypoglycemic agents. 相似文献
1000.
El-Mahdy Reham I. Mostafa Mohammed Mahmoud EL-Deen Hanan Sharaf 《Applied biochemistry and biotechnology》2019,188(1):208-224
Applied Biochemistry and Biotechnology - Despite advances in the management of cardiovascular diseases, acute coronary syndrome (ACS) remains the leading cause of death worldwide. ACS is associated... 相似文献