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31.
The (37MBq) 99mTc-MIBI complex samples were prepared due to ultrasound irradiation technique or boiled water bath method as a standard method. The qualitative and quantitative studies have been performed. The accumulation of 99mTc-MIBI complexes prepared by two above mentioned modalities were approximately 3 ± 0.1 % in the rats’ heart. The ultrasound irradiation technique is recommended to prepared 99mTc-MIBI complex in efficiently amount. Our approach can potentially reduce medical risk to the patient by avoiding any delay in acute therapy particularly for myocardial infarction patients.  相似文献   
32.
<正>A potential biodegradable and optically active bulky chiral aromatic amide-imidic diacid monomer,(2S,3S)-5-(3- methyl-2-phthalimidylpentanoylarnino)isophthalic acid(7),containing a rigid phthalimide and flexible L-isoleucine pendant group was synthesized in three steps.New aromatic polyamides including pendant phthalimido groups and flexible side spacers have been synthesized by direct polycondensation reaction of equimolar amounts of different aromatic diamines with an optically active diacid 7,using N-methyl-2-pyrrolidone(NMP) as a solvent and triphenyl phosphite/CaCl_2/pyridine as a condensing agent.These polyamides were characterized by FTIR,~1H-NMR spectroscopy,specific rotation, thermogravimetric and elemental analysis.The resulting polymers have inherent viscosities in the range of 0.21-0.45 dL/g. Amino acid existence in this backbone results in optically active polymers.Due to introduction of bulky and flexible groups in these polyamides,they show improved solubility in polar aprotic solvents such as NMP and dimethylacetamide and also good thermal stability(10%weight loss temperatures in excess of 330℃,and char yields at 600℃in nitrogen higher than 62%).  相似文献   
33.
An environmentally green method for the synthesis of 13-aryl-5H-dibenzo[b,i]xanthene-5,7,12,14(13H)-tetraone and 3,4-dihydro-1H-benzo[b]xanthene-1,6,11(2H,12H)-trione derivatives using Brønsted acidic ionic liquids, 3-methyl-1-sulfonic acid imidazolium chloride, 1-H-3-methyl-imidazolium hydrogensulfate, triethylamine-bonded sulfonic acid, and triethylammonium hydrogensulfate as reusable catalysts under thermal solvent-free conditions is described.  相似文献   
34.
A new polypyridyl Ru (II) complex, cis-[Ru (Me4phen)2(CH3CN)2](NO3)2 (Me4phen = 3,4,7,8-tetramethyl-1,10-phenanthroline) has been prepared and fully characterized by elemental analysis, X-ray crystallography, cyclic voltammetry and spectroscopic techniques. The solid-state structure of the complex indicated that the Ru (II) center is sitting in an N4N′2 coordination environment with a distorted octahedral geometry. Cyclic voltammetry technique was used to investigate the catalytic activity of the Ru (II) complex on the electrocatalytic reduction of CO2 to CO in acetonitrile. The effect of the different reaction parameters, including the scan rate, concentration of the electrocatalyst [complex Ru (II)] and reaction temperature, on the catalytic activity was also investigated. The results showed that the electrocatalytic activity of the complex increases with increasing electrocatalyst concentration and scan rate. Further, the CO2 reduction peak current decreases at lower temperatures owing to the inverse relationship between the temperature and activation energy. The theoretical calculations confirmed the proposed electrocatalytic mechanism comprising seven steps.  相似文献   
35.
In this paper, we report the experimental results of a pulsed flash lamp Nd:YAG laser at wavelength of 1064 nm and Q-switched by Cr4+:YAG solid state saturable absorber. We have obtained the output energy (E) and pulse- width (τp) of this laser for various initial transmissions of this saturable absorber. Furthermore, the effect of reflectivity of the output coupler (R), diameter of the rod (d), and optical length of the cavity (l) on this laser output data have been investigated. We have used the corner cube as a back mirror, which shows high laser stability and better brightness. We have obtained pulse-width 15 ns with 31 mJ output energy. We have also analyzed this laser theoretically and analytically, which agrees well with our corresponding experimental results.  相似文献   
36.
In the present study, H-Mg-H···X···Y (X = Li+, Na+ and Y = C2H2, C2H4, C6H6) triads have been investigated at MP2/6-311++G(2d,2p) computational level to characterise cooperative effects between hydride bonding and cation–π interactions. Molecular geometries, binding energies, cooperative energies and many-body interaction energies were evaluated. The diminutive energy values in triads with Li+ are larger than respective values in triads with Na+. The electronic properties of the complexes are analysed using parameters derived from the quantum theory of atoms in molecules methodology.  相似文献   
37.
A theoretical model is described here for studying the effect of temperature on nanomaterials. The thermodynamic equation of state (EoS) proposed by Goyal and Gupta in High Temp.-High Press. 45, 163 (2016); Oriental J. Chem. 32(4), 2193 (2016), is extended in the present study using Qi and Wang model [Mater. Chem. Phys. 88, 280 (2004)]. The thermal expansion coefficient is expressed in terms of shape and size and used to obtain the isobaric EoS of nanomaterials for the change in volume \(V/{V_0}\). The variation in \(V/{V_0}\) with temperature is estimated for spherical nanoparticles, nanowires and nanofilms. It is found that the volume thermal expansivity decreases as size of the nanomaterial increases, whereas \(V/{V_0}\) increases with temperature across nanomaterials of different sizes. The lattice parameter variation with temperature is studied in Zn nanowires, Se and Ag nanoparticles. It is found that lattice constant increases with increase in temperature. Also, bulk modulus is found to increase with temperature in nanomaterials. The results obtained from the present model are compared with the available experimental data. A good consistency between the compared results confirms the suitability of the present model for studying thermal properties of the nanomaterials.  相似文献   
38.
New N-glycosides based on valproic acid analogs tetrazole derivatives were synthesized. The bis-tetrazole derived from 1,6-hexandiol was also connected to acetylated glucose and formed bis-N-glycoside. Structures characterizations have been performed using FT IR, 1H and 13C NMR spectroscopy.  相似文献   
39.
Research on Chemical Intermediates - Bisulfate-functionalized dicationic ionic liquid grafted with silica-coated nano-Fe3O4 (nano-[Fe3O4@SiO2@BDIL] or NFSBDI) was synthesized as a novel...  相似文献   
40.
The mechanism and kinetics of the reaction of hydrogen sulphide (H2S(1A1)) with hydroperoxyl radical (HO2(2A″)) on the lowest doublet potential energy surface have been theoretically studied. The potential energy surface for possible pathways has been investigated by employing Complete Basis Set (CBS), DFT, and CCSD(T) methods. Three possible pathways are suggested for the title reaction. The most probable entrance channel consists of formation of a hydrogen-bonded pre-reaction complex (vdw1) and two energised intermediates. Multichannel RRKM-Steady State Approximation and CVT calculations have been carried out to compute the rate constants over a broad range of temperature from 200?K to 3000?K to cover the atmospheric and combustion conditions and pressure from 0.1 to 2000?Torr. No sign of pressure dependence was observed for the title reaction over the stated range of pressure. We have shown that the major products of the title reaction are H2O2 and SH while at higher temperatures, formation of the other products such as H2O, HOS, HSOH and OH are feasible, too. Our calculated overall rate constant is in agreement with the reported experimental data in the literature.  相似文献   
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