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111.
112.
Ravindran S Andavan GT Tsai C Ozkan CS Hollis TK 《Chemical communications (Cambridge, England)》2006,(15):1616-1618
Fabrication of perforated organometallic nanotubes using a di-rhodium bis(N-heterocyclic carbene) complex by a simple nanoporous template wetting technique is described along with characterization data from scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), proton NMR and Mass spectroscopy. 相似文献
113.
A. Kahoul V. Aylikci N. Kup Aylikci E. Cengiz G. Apaydın 《Radiation Physics and Chemistry》2012,81(7):713-727
The measured K-shell fluorescence yield values that were reported in the literature from 1994 to 2011 were reviewed and presented in a table form (about 341 new measurements). The Weighted-mean values of experimental data were fitted by the analytical function to deduce new empirical K-shell fluorescence yields for a broad range of elements. The results were compared with the other theoretical, experimental and semi-empirical values reported in the literature. Reasonable agreement was typically obtained between our result and other works. 相似文献
114.
Small organic molecules are promising candidates for cheaper, flexible and good‐performance sources for organic solar cells (OSCs) due to their easy fabrication, low cost and slightly cheaper processing. However, the lower power conversion efficiency of OSCs is the main problem for their applications. Ferrocene structures could be the best candidates for the active layers of OSCs due to their unique properties such as thermal and chemical stability. The electrochemical, electro‐optical and solar cell performances of 2,5‐dicyano‐3‐ferrocenyl‐4‐ferrocenylethynylhexa‐2,4‐dienedinitrile (DiCN‐Fc) structures were investigated. First, the electrochemical and electro‐optical properties were examined for finding the highest occupied and lowest unoccupied molecular orbital values and bandgap of DiCN‐Fc. The best photovoltaic performance was obtained with 7 wt% of DiCN‐Fc loading, with a power conversion efficiency of about 4.27%. In the light of our investigations, ferrocenyl‐substituted small organic molecules could contribute to the development of organic photovoltaic devices. 相似文献
115.
JPC – Journal of Planar Chromatography – Modern TLC - The study reported in this paper was aimed to develop an accurate, specific, and precise high-performance thin-layer chromatography... 相似文献
116.
Omer Kaygili Serhat Keser Cengiz Tatar Suleyman Koytepe Tankut Ates 《Journal of Thermal Analysis and Calorimetry》2017,128(2):765-770
A glass with the composition of the SiO2–Na2O–CaO–P2O5 was synthesized by sol–gel method at temperature of 900 °C, and then yttrium-, silver- and cerium-containing glasses were prepared at the same conditions using this base system. The structural and thermal properties of the glass samples were investigated by X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy, energy-dispersive X-ray (EDX) spectroscopy and differential thermal analysis techniques. The Ca5(PO4)2(SiO4)6 phase having the orthorhombic crystal system is detected for each sample without any secondary phase, and this phase is confirmed by the FTIR spectra. With the addition of Y, Ag and Ce to the SiO2–Na2O–CaO–P2O5 system, the variations in the average crystallite size, crystallinity percent, lattice parameters and unit cell volume are observed. A decrease in the crystallization peak temperature and the changes in the glass transition temperature are seen with the addition of Y, Ag and Ce to the base system. The addition of Y, Ag and Ce to the base glass increases significantly its density. The EDX spectra of the as-prepared samples verify the introduction of the as-mentioned elements. 相似文献
117.
Mustafa Eskici Abdullah KaranfilM. Sabih Özer Cengiz Sar?kürkcü 《Tetrahedron letters》2011,52(48):6336-6341
A synthetically useful level of reactivity of cyclic sulfamidates toward acetylides is described. Ring-opening reactions of a structurally diverse set of 1,2- and 1,3-cyclic sulfamidates with a range of lithium acetylides from aliphatic, cyclic, aromatic, heteroaromatic, and functionalized alkynes proceed smoothly in a regioselective manner to give the corresponding N-sulfate intermediates. Hydrolysis of these intermediates under acidic conditions furnishes the alkynylated amines in yields ranging from 29% to 98%. The scope of the acetylenic substitution reaction with the structural variations in both the cyclic sulfamidates and alkynes is briefly examined. 相似文献
118.
Süleymanoğlu N Ustabaş R Alpaslan YB Eyduran F Ozyürek C Iskeleli NO 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,83(1):472-477
In this work, 3,4-bis(isoproylamino)cyclobut-3-ene-1,2-dione C(10)H(16)N(2)O(2) (I), was synthesized and characterized by (13)C NMR, (1)H NMR, FT-IR, UV-vis spectroscopy and single-crystal X-ray diffraction. DFT method with 6-31G(d,p) basis set has been used to calculate the optimized geometrical parameters, atomic charges, vibrational frequencies and chemical shift values. The calculated vibrational frequencies and chemical shift values are compared with experimental FT-IR and NMR spectra. The results of the calculation shows good agreement between experimental and calculated values of the compound I. The existence of N-H?O type intermolecular ve C-H?O type intramolecular hydrogen bonds can be deduced from differences between experimental and calculated results of FT-IR and NMR. In addition, the molecular electrostatic potential map and frontier molecular orbitals and electronic absorption spectra were performed at B3LYP/6-31G(d,p) level of theory. HOMO-LUMO electronic transition of 4.90 eV are derived from the contribution of the bands π→π* and n→π* The spectral results obtained from FT-IR, NMR and X-ray of I revealed that the compound I is in predominantly enamine tautomeric form, which was supported by DFT calculations. 相似文献
119.
Eyüp Özdemidotr Cengiz Soykan Mehmet Coşkun Misir A. Ahmedov 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(3):551-557
Abstract Phenacylmethacrylate (PAMA), a new monomer containing two carbonyl groups (C[dbnd]O), was obtained from phenacyl chloride and sodium methacrylate. The homopolymer of PAMA and its copolymer with styrene were prepared in dioxane by using benzoylperoxide (Bz2O2) as initiator. IR, 1H-NMR and 13C-NMR techniques were used to identify the structure of the monomer and polymers. The density of monomer, homopolymer and copolymer were found to be 1.13; 1.35 and 1.10 gr/ml respectively. Also, limit viscosity numbers, solubility parameters, glass transition and decomposition temperatures of polymers were determined. 相似文献
120.