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91.
A novel quadridentate, N2O2 type Schiff base, synthesized from 1,4‐bis‐(o‐aminophenoxy)butane and 2‐hydroxynaphthalin‐1‐carbaldehyde, forms stable complexes with transition metal ions such as Co(II), Cu(II) and Ni(II) in DMF. Microanalytical data, elemental analysis, magnetic measurements, UV‐visible and IR‐spectra as well as conductance measurements were used to confirm the structures. Electrochemical measurements show that metal complexes undergo quasi‐reversible one‐electron redox processes. The voltammetric results also revealed that the CuL complex has the highest electron transfer rate indicating that both the Cu(II) and Cu(I) forms appear in a similar planar configuration, so the electron transfer does not require larger reorganization of the complex. 相似文献
92.
1,3‐Diarylsubstituted imidazolinium salts, (NHC‐H)Cl, 3, containing hydrogen or alkyl groups at the 4,5‐positions of the imidazolidine ring, served as precursors to rhodium(I) complexes [RhCl(NHC)COD], 4, which were converted into cis‐[RhCl(NHC)(CO)2] complexes, 5. All compounds prepared were characterized by elemental analyses, 1H NMR and 13C NMR. The relative σ‐donor/π‐acceptor strength of the NHC ligands was determined by means of IR spectroscopy of 5. The ability of NHCs in 4 to enchance activity was explored in the 1,2‐addition of phenylboronic acid to aldehydes. A good correlation was observed between catalytic activity and the electron‐donating power of the NHC ligands. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
93.
94.
Bekir Çak?r Yusuf Yakar Ayhan Özmen M. Özgür Sezer Mehmet ?ahin 《Superlattices and Microstructures》2010
The binding energy and wavefunctions of the 1s, 1p, 1d and 1f energy states of a spherical quantum dot (QD) with parabolic potential were calculated by using a method which is a combination of the quantum genetic algorithm (QGA) and the Hartree–Fock–Roothaan (HFR) approach. In addition, the linear and the third-order nonlinear optical absorption coefficients based on optical transitions in QDs with and without impurity were calculated. The results show that the parabolic potential has a great effect not only on the binding energies and but also on the optical absorption coefficients. Moreover, the calculated results also reveal that the linear and nonlinear optical absorption coefficients are strongly affected by the existence of impurity and the incident optical intensity. 相似文献
95.
F. Doğan M. Ulusoy Ö. F. Öztürk İ. Kaya B. Salih 《Journal of Thermal Analysis and Calorimetry》2009,96(1):267-276
The thermal decomposition kinetics of sterically hindered salen type ligand (L) and its metal complexes [M=Co(II), Ni(II), Cu(II)] were investigated by thermogravimetric analysis. A direct insertion probe-mass spectrometer (DIP-MS)
was used for the characterization of metal complexes of L and all fragmentations and stable ions were characterized. The thermogravimetry and differential thermogravimetry (TG-DTG)
plots of salen type salicylaldimine ligand and complexes showed a single step.
The kinetic analysis of thermogravimetric data was performed by using the invariant kinetic parameter method (IKP). The values
of the invariant activation energy, E
inv and the invariant pre-exponential factor, A
inv, were calculated by using Coats-Redfern (CR) method. The thermal stabilities and activation energies of metal complexes of
sterically hindered salen type ligand (L) were found as Co(II)>Cu(II)>Ni(II)>L and E
Cu>E
Ni>E
Co>L. Also, the probabilities of decomposition functions were investigated. The diffusion functions (D
n) are most probable for the thermal decomposition of all complexes. 相似文献
96.
Filiz Tascan Ahmet Bekir Murat Koparan 《Communications in Nonlinear Science & Numerical Simulation》2009,14(5):1810-1815
In this paper, we established travelling wave solutions for some (2 + 1)-dimensional nonlinear evolution equations. The first integral method was used to construct travelling wave solutions of nonlinear evolution equations. The travelling wave solutions are expressed by the hyperbolic functions, the trigonometric functions and the rational functions. The first integral method presents a wider applicability for handling nonlinear wave equations. 相似文献
97.
Salih Djilali 《Journal of Applied Analysis & Computation》2019,9(2):638-654
In this paper, we deal with the effect of the shape of herd behavior on the interaction between predator and prey. The model analysis was studied in three parts. The first, The
analysis of the system in the absence of spatial diffusion and the time delay, where the local stability of the equilibrium states, the existence of Hopf bifurcation have been investigated. For the second part, the spatiotemporal dynamics introduce by self diffusion was determined, where the existence of Hopf bifurcation, Turing driven instability, Turing-Hopf bifurcation point have been proved. Further, the order of Hopf bifurcation points and regions of the stability of the non trivial equilibrium state was given. In the last part of the paper, we studied the delay effect on the stability of the non trivial equilibrium, where we proved that the delay can lead to the instability of interior equilibrium state, and also the existence of Hopf bifurcation. A numerical simulation was carried out to insure the theoretical results. 相似文献
98.
Jumat Salimon Nadia Salih Emad Yousif Ayad Hameed Ayad Kreem 《Arabian Journal of Chemistry》2010,3(4):205-210
In the present study a new acridone derivatives were synthesized. The newly synthesized compounds were characterized by IR, NMR and C, H, N, S analyses. All newly synthesized compounds were screened for their antibacterial (Staphylococcus aureus, Streptococcus viridans and Escherichia coil) and antifungal (Gibberela, Cercospora arachidicola, Physolospora piricola and Fusarium oxysporum) studies. The results revealed that all synthesized compounds have a significant biological activity against the tested microorganisms. 相似文献
99.
Applications of fractional complex transform and $\left( \frac{G^{\prime }}{G}\right) $-expansion method for time-fractional differential equations 下载免费PDF全文
Ahmet Bekir Ozkan Guner Omer Unsal Mohammad Mirzazadeh 《Journal of Applied Analysis & Computation》2016,6(1):131-144
In this paper, the fractional complex transform and the $\left( \frac{G^{\prime }}{G}\right) $-expansion method are employed to solve the time-fractional modfied Korteweg-de Vries equation (fmKdV),Sharma-Tasso-Olver, Fitzhugh-Nagumo equations, where $G$ satisfies a second order linear ordinary differential equation. Exact solutions are expressed
in terms of hyperbolic, trigonometric and rational functions. These solutions may be useful and desirable to explain some nonlinear physical phenomena in genuinely nonlinear fractional calculus. 相似文献
100.
Naciye Bihter Taylan Bekir Sari Halil Ibrahim Unal 《Journal of Polymer Science.Polymer Physics》2010,48(12):1290-1298
This study covers the synthesis of conducting polyindole (PIN) homopolymer, poly(vinyl chloride)/polyindole (PVC/PIN) composites, and preparation of their freestanding films. PIN and composites were synthesized chemically by radicalic mechanism using FeCl3 as an initiator. Films of PVC and PVC/PIN composites were prepared by casting on glass Petri dishes. Mechanical properties of films were examined by stress–strain experiments. From FTIR spectra of polymers, it was revealed that polymerization reaction occurred by 2–3 mechanism. The conductivities of polymers at different temperatures were also measured by four‐probe technique and found in the range 10?4 to 10?5 S cm?1. Magnetic properties of the polymers were analyzed by Gouy scale measurements and were found that their conducting mechanisms are of polaron and bipolaron natures. Thermal properties of polymers were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) and found that they had shown adequate thermal stability. X‐ray diffraction (XRD) spectra showed the amorphous nature of the polymers. Scanning electron microscopy (SEM) was used for microstructural analysis. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1290–1298, 2010 相似文献