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61.
Amir Hayati 《Molecular physics》2020,118(6)
We investigate the heat dissipation mechanism in the Benzene molecular junctions. Using the tight-binding model and the generalised Green’s function formalism, heat dissipation in the electrodes is studied numerically. Results reveal a strong dependence of heat dissipation on the transmission characteristics and the bill polarity. For a pure Benzene molecular junctions, regardless the electrodes positions, namely meta, ortho and para configurations, heat dissipates in a symmetric fashion at both electrodes and does not rely on the bias polarity. This feature is a consequence of a symmetric transmission function over the energy spectrum of incoming electrons. Introducing a single impurity on the Benzene molecule, we force the model to lose its particle-hole symmetry and a drastic change occurs in the heat dissipation of the junction. 相似文献
62.
Ayegül Gk Bekir Sari Muzaffer Talu 《Journal of Polymer Science.Polymer Physics》2004,42(18):3359-3367
This article deals with the chemical synthesis and characterization of poly(2‐fluoroaniline) (P2FAn) and polyfuran (PFu) homopolymers and PFu/P2FAn and P2FAn/PFu composites. P2FAn and PFu homopolymers were synthesized using ammonium persulfate and antimony (III) chloride as catalyst, respectively. These homopolymers and composites were studied in the doped state using Fourier transform infrared spectroscopy and ultraviolet–visible absorption spectroscopy, thermogravimetric analysis, scanning electron microscopy, four‐probe conductivity technique, and Gouy Scale measurements. PFu/P2FAn and P2FAn/PFu composites were found to possess different thermal, conductivity, electronic, and morphological properties from each other when synthesis order of guest and host polymers was varied. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3359–3367, 2004 相似文献
63.
M. Aksu S. Durmu M. Sari K. C. Emregül I. Svoboda H. Fuess O. Atakol 《Journal of Thermal Analysis and Calorimetry》2007,90(2):541-547
N,N′-bis(salicylidene)-1,3-propanediamine (LH2), N,N′-bis(salicylidene)-2,2′-dimethyl-1,3-propanediamine (LDMH2), N,N′-bis(salicylidene)-2-hydroxy-1,3-propanediamine (LOH3), N,N′-bis(2-hydroxyacetophenylidene)-1,3-propanediamine (LACH2) and N,N′-bis(2-hydroxyacetophenone)-2,2′-dimethyl-1,3-propanediamine (LACDMH2) were synthesized and reduced to their phenol-amine form in alcoholic media using NaBH4 (LHH2, LDMHH2, LOHHH2, LACHH2 and LACDMHH2). Heterodinuclear complexes were synthesized using Ni(II), Zn(II) and Cd(II) salts, according to the template method in DMF
media.
The complex structures were analyzed using elemental analysis, IR spectroscopy, and thermogravimetry. Suitable crystals of
only one complex were obtained and its structure determined using X-ray diffraction, NiLACH·CdBr2·DMF2, space group orthorhombic, Pbca, a=20.249, b=14.881, c=20.565 ? and Z=8. The heterodinuclear complexes were seen to be of [Ni·ligand·MX2·DMF2] structure (ligand=LH2−, LDMH2−, LOHH2−, LACH2−, LACDMH2−, M=ZnII, CdII, X=Br−, I−). Thermogravimetric analysis showed irreversible bond breakage of the coordinatively bonded DMF molecules followed by decomposition
at this temperature. 相似文献
64.
Aydin Tavman Mustafa Hayvali Hayati Filik Emine Kiliç 《Russian Journal of Inorganic Chemistry》2006,51(8):1198-1201
The complexes of 2,2′-(1,4-Phenylenedivinylene)-bis-8-hydroxyquinoline (LH2) with K2PdCl4, H2PtCl6 and HAuCl4 were synthesized and characterized with 1H-and 13C-NMR, elemental analysis, FT-IR, and molar conductivity. Au(III) and Pt(IV) complexes have characteristic conductance, while
the Pd(II) complex has a non-ionic structure according to the molar conductivity and elemental analysis.
This text was submitted by authors in English. 相似文献
65.
66.
Banti Christina N. Poyraz Mehmet Sainis I. Sari Musa Rossos G. Kourkoumelis N. Hadjikakou Sotiris K. 《Molecular diversity》2020,24(1):31-43
Molecular Diversity - Two complexes of Zn(II) and Ni(II) ions with the urea derivative, 2-benzimidazolyl-urea (BZIMU), of formulae [ZnBZIMU)2(H2O)](NO3)2 (1) and [Ni(BZIMU)2(CH3CH2OH)2](NO3)2 (2)... 相似文献
67.
Using a variational approach, we have calculated the hydrostatic pressure and temperature effects on the donor impurity related photoionization cross-section and impurity binding in GaAs/GaAlAs quantum dots. Our calculations have revealed the dependence of the photoionizaton cross-section and the impurity binding on temperature and hydrostatic pressure. 相似文献
68.
69.
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
70.
A. Zare A. Hasaninejad A. Khalafi-Nezhad A. R. Moosavi-Zare M. H. Beyzavi F. Khedri F. Asadi N. Hayati A. Asifi 《Journal of the Iranian Chemical Society》2010,7(2):461-469
A highly efficient and simple method for the synthesis of N-aryl derivatives of pyrimidine and purine nucleobases via Narylation of nucleobases using zinc oxide in 1-butyl-3-methylimidazolium bromide ([bmim]Br) under microwave as well as thermal conditions is described. In both conditions, the title compounds were produced in high to excellent yields and in short reaction times. 相似文献