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81.
Tandem reaction between acyl isoselenocyanates, generated from acyl chlorides and KSeCN, and benzene‐1,2‐diamine in acetone at room temperature, gave 1,3,5‐triazepineselone derivatives in moderate to good yields.  相似文献   
82.
Visible light‐driven Al‐doped TiO2 with different aluminum contents (2, 5 and 10 mol%) were synthesized via a facile sol–gel method. Fourier transform infrared (FTIR), UV‐visible diffuse reflectance, energy dispersive Xray (EDX) spectroscopy as well as X‐ray diffraction (XRD), X‐ray fluorescence (XRF) and scanning electron microscopy (SEM) methods were used for the characterization of the obtained nanoparticles. The photocatalytic performance of the samples was evaluated by the degradation of rhodamine B (RhB) under visible light irradiation. The yield of the degradation RhB was estimated to be 71%, 89%, 65% and 56%, for the bare TiO2, 2%, 5% and 10% Al‐doped TiO2, respectively. It was found that 2 mol% of Al‐doped TiO2 shows the best photocatalytic performance. In low concentration of dopant, separation of photogenerated electron–hole pairs promoted, and subsequently, the degradation efficiency increased. It was proposed that the degradation of RhB by 2 mol% Al‐doped TiO2 photocatalyst follows both N‐deethylation and chromophore cleavage mechanisms, while the N‐deethylation still predominated over cleavage of dye chromophore structure. The key role of hydroxyl radicals in RhB degradation was verified by the effects of scavengers. In addition, the photocatalyst can be reused for three runs without any significant loss of its catalytic activity.  相似文献   
83.
The proton transfer compound LH2 , (phenH+)2(pydc2—), has been prepared from 1, 10‐phenanthroline, phen, and 2, 6‐pyridinedicarboxylic acid, (dipicolinic acid), pydcH2. Characterization was performed using solution and solid phase CP/MAS 13C NMR and IR spectroscopy. The reactions of this adduct with ZnSO4·7H2O and Zn(NO3)2·4H2O give the complexes, [Zn(pydc)2][Zn(phen)2(H2O)2]·7H2O (1) and [Zn(phen)3]4(H(Hpydc)2)(NO3)7·26H2O (2) , respectively. These complexes were characterized by 1H and 13C NMR spectroscopy and single crystal X‐ray analysis. The complexes crystallize in the triclinic space group P1 with Z = 2. The unit cell dimensions for complex 1 and 2 are: a = 9.9838(9) Å, b = 14.7483(13) Å, c = 14.8365(13) Å and a = 12.640(4) Å, b = 15.855(5) Å, c = 21.830(7) Å, respectively. In complex 1 (pydc2—) and phen, are tri‐ and bidentate ligands, respectively, and an anionic [Zn(pydc)2]2— and cationic [Zn(phen)2(H2O)2]2+ complex are formed simultaneously. In complex 2 , three phen participate in complexation leaving hydrogen‐bis(pyridine‐2‐carboxylate), (H(Hpydc)2) as a supramolecular anion. The fragments (H(Hpydc)2), 7 NO3, and 26 H2O in complex 2 are joined together by extensive and strong H‐bonding; therefore, the structure is composed of [Zn(phen)3]48+, and an anionic hydrogen bond supramolecular assembly with the formula, {(H(Hpydc)2(NO3)7)8— · 26H2O}n. The anionic species (H(Hpydc)2) has a special position at the inversion center, as well as one of the NO3 anions, which is disordered over the inversion center. Most of the hydrogen bonds in complex 2 represent strong H‐bonding. The protonation constants of the building blocks of the pydc‐phen adduct, the equilibrium constants for the reaction of (pydc2—) with phenanthroline and the stoichiometry and stability of the ZnII complex with LH2 on aqueous solution were determined by potentiometric pH titration. The solution study results support self‐association between (pydc2—) and (phenH+) with a stoichiometry for the Zn(II) complex similar to that observed for the isolated crystalline complex.  相似文献   
84.
Microchimica Acta - Copper nanoclusters (CuNCs) are an attractive alternative to other metal nanoclusters. The synthesis of CuNCs is highly efficient and fast, with low-cost and without any...  相似文献   
85.
86.
Journal of Solid State Electrochemistry - A non-enzymatic sensor was developed for simultaneous detection of glucose, ethanol, and glycerol concentrations in wine using nickel nanoparticles on...  相似文献   
87.
Natural hydroxyapatite‐supported MnO2 (MnO2@NHAp) was easily prepared in situ from reduction of potassium permanganate with natural hydroxyapatite derived from cow bones in water at room temperature, and its structure was characterized using flame atomic absorption spectroscopy, X‐ray diffraction, thermogravimetric analysis, scanning electron microscopy and energy dispersive spectroscopy. The catalytic activity of the synthesized catalyst was investigated for the aerobic oxidation of alkylarenes and alcohols. MnO2@NHAp shows excellent catalytic performance for the oxidation of alkylarenes and alcohols to their corresponding carbonyl compounds without using any other oxidizing agent. This catalyst can be readily recycled and reused for several runs without any significant loss of efficiency. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
88.
Journal of Inclusion Phenomena and Macrocyclic Chemistry - Beta-carotene (BC) is a vitamin A precursor and has potential anticancer benefits, but the delivery of BC is hindered by its low...  相似文献   
89.
Nonlinear Dynamics - This paper focuses on finding soliton solutions for an intrinsic fractional discrete nonlinear electrical transmission lattice. Our investigation is based on the fact that for...  相似文献   
90.
Nanomagnetic bisethylferrocene‐containing ionic liquid supported on silica‐coated iron oxide (Fe3O4@SiO2@Im‐bisethylFc [HC2O4]) as a novel catalyst was designed and synthesized. The described catalyst was recycled and used without change in the time and efficiency of the condensation reaction. The Fourier transform‐infrared spectroscopy (FT‐IR), scanning electron microscopy images, X‐ray diffraction patterns, energy‐dispersive X‐ray spectroscopy, transmission electron microscope and vibrating‐sample magnetometer results confirmed the formation of Fe3O4@SiO2@Im‐bisethylFc [HC2O4] magnetic nanoparticle. The novel bis‐coumarin derivatives were identified by 1H‐NMR, 13C‐NMR, FT‐IR and CHNS analysis.  相似文献   
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