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101.
Gel electrolytes and solid electrolytes have been reported as a potential element to slow down the polysulfide shuttle by reducing its mobility in the electrolytes. The preparation of sulfur-conductive polymer composites, or sulfur-carbon composites, has been reported as softening the impact of the shuttle effects. Unlike Li-ion batteries so far, no electrolyte is found to be optimal for Li–S batteries at all conditions. Taking into account all these factors, in the present study, an attempt has been made to develop solid polymer electrolytes in conjunction with non-aqueous liquid electrolytes along with inert fillers for Li–S batteries. Poly-ethylene oxide (PEO)-based composite gel polymer electrolytes (CGPE) comprising a combination of plasticizers, namely 1,3-dioxolane (DIOX)/tetraethylene glycol dimethylether (TEGDME) and a lithium salt (LiTf) with the addition of ceramic filler, barium titanate (BaTiO3) have been prepared using a simple solution casting technique in an argon atmosphere. The as-prepared polymer electrolyte films were subjected to SEM, ionic conductivity, TG/DTA, and FTIR analyses. A symmetric cell composed of Li/CGPE/Li was assembled, and the variation of interfacial resistance as a function of time was also measured. The ionic conductivity was found to be increased as a function of temperature. The lithium transference number (Lit +) was measured, and the value was calculated as 0.7 which is sufficient for battery applications. The electrochemical stability window of the sample was studied by linear sweep voltammetry, and the polymer electrolyte film was found to be stable up to 5.7 V. The TG/DTA analysis reveals that this CGPE is thermally stable up to 350 °C. The compatibility studies exhibited that CGPE has better interracial properties with lithium metal anode. The interaction between the PEO and salt has been identified by an FTIR analysis. 相似文献
102.
S. Kannan S. Chantrapromma H. K. Fun S. Robinson Jebas 《Journal of chemical crystallography》2009,39(1):9-12
Abstract The crystal structures for two of the ligands C6H5CH2SOCH2CONHCH2C6H5 (1) and C6H5SOCH2CON(iC3H7)2 (2) have been determined by X-ray diffraction. These compounds crystallize in orthorhombic system with space groups and cell
parameters, Pca21(no. 29), a = 8.4600(5) ?, b = 5.3534(5) ?, c = 32.136(2) ?, V = 1455.42(15) ?3 and Pna21(no. 33) a = 17.5563(11) ?, b = 5.7902(4) ?, c = 14.2866(9) ?, V = 1452.30(16) ?3, respectively. These molecules are stabilized in solid state by various intra and intermolecular hydrogen bonding interactions
to give polymeric structures. The reported IR spectra of these compounds in solid state could be explained on the basis of
the observed intermolecular hydrogen bonding interactions.
Index Abstract The title compounds C6H5CH2SOCH2CONHCH2C6H5 (1) and C6H5SOCH2CON(iC3H7)2 (2) were prepared by the oxidation of corresponding sulfides with H2O2/SeO2 in methanol and their structures were determined. The structures show that the SO and CO groups are having “anti” configuration
in 1 and “syn” configuration in 2.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
103.
The bi-functional carbamoyl methyl pyrazole ligands, C5H7N2CH2CONBu2 (L1), C5H7N2CH2CONiBu2 (L2), C3H3N2CH2CONBu2 (L3), C3H3N2CH2CONiBu2 (L4) and C5H7N2CH2CON(C8H17)2 (L5) were synthesized and characterized by spectroscopic and elemental analysis methods. The selected coordination chemistry of L1 to L4 with [UO2(NO3)2 · 6H2O], [La(NO3)3 · 6H2O] and [Ce(NO3)3 · 6H2O] has been evaluated. Structures for the compounds [UO2(NO3)2 C5H7N2CH2CONBu2] (6) [UO2(NO3)2 C5H7N2CH2CONiBu2] (7) and [Ce(NO3)3{C3H3N2CH2CONiBu2}2] (11) have been determined by single crystal X-ray diffraction methods. Preliminary extraction studies of the ligand L5 with U(VI) and Pu(IV) in tracer level showed an appreciable extraction for U(VI) and Pu(IV) up to 10 M HNO3 but not for Am(III). Thermal studies of the compounds 6 and 7 in air revealed that the ligands can be destroyed completely on incineration. 相似文献
104.
Challenges encountered in the analysis of phthalate esters in foodstuffs and other biological matrices 总被引:2,自引:0,他引:2
Phthalate esters are ubiquitous environmental pollutants and are recognized as environmental endocrine disruptors because of their potential to elicit reproductive and developmental toxicity. Several phthalate esters have been listed by the US Environmental Protection Agency (EPA) as chemicals of concern. Determination of concentrations of phthalate esters in foodstuffs, typically present at sub to low nanogram-per-gram concentrations (between 0.1 and 100?ng?g?1), is essential for assessment of human dietary exposure. However, phthalate esters are commonly present as contaminants in several laboratory products, including organic solvents, that are used in sample preparation and analysis. Therefore, accurate analysis of phthalates in food samples is a challenging task. In this review, we summarize the methods available for the determination of phthalate esters in foodstuffs and report on concentrations of phthalates in foodstuffs and potential sources of contamination by phthalates in the analysis of foodstuffs. We offer suggestions to eliminate and/or reduce background levels of contamination by phthalates in the analysis of food and other biological samples. We also introduce methods that are suitable for trace analysis of phthalates in a variety of liquid and solid food samples, in particular, a liquid–liquid extraction method for removal of lipids from food samples, because these can substantially reduce background levels of phthalates in the analytical procedure. 相似文献
105.
1((Cyclohexylamino)methyl)urea Mannich base was synthesized and characterized using FT-IR, H1NMR and C13NMR spectra and it was tested as a corrosion inhibitor for mild steel in 1?N HCl and 1?N H2SO4 solutions using potentiodynamic polarization and AC impedance techniques over the temperature range of 303?C333?K. The inhibition efficiency was increased with respect to concentration of inhibitor and temperature in 1?N HCl, whereas the inhibition efficiency was increased with respect to concentration of inhibitor and decreased with respect to temperature in 1?N H2SO4. Potentiodynamic polarization results revealed that the inhibitor acts as mixed type inhibitor. AC impedance study indicates that the corrosion of steel was mainly controlled by a charge transfer process. Surface analysis was carried out using SEM technique. The adsorption of inhibitor follows Langmuir adsorption isotherm. Activation and adsorption parameters were calculated to gain information about the inhibitive action mechanism. 相似文献
106.
The local (plate)/global (beam) vibration and damping behavior of composite thin-walled box member subjected to vibratory environment are studied and presented in this paper. This investigation is carried out by the use of 3D beam and thin plate finite elements and the corresponding modal frequencies/damping values of composite box beam are predicted by modal strain energy method. Application examples illustrate the ability of the 3D beam and thin plate element to predict both local and global modal frequencies/damping of hollow box sections. The influence of L/h ratio, b/h ratio and ply angle on the frequency and loss factor of composite box beam is investigated. In addition, an attempt has also been made to investigate the effect of temperature on the composite damping characteristics of rectangular box type section. 相似文献
107.
K. Rameshbabu P. Kannan M. Gunasekaran P. Srinivasan R. Ramesh Babu R. Gopalakrishnan P. Ramasamy 《Crystal Research and Technology》2006,41(7):718-722
4,4′‐dihydroxy‐α‐methylstilbene (DHAMS) was synthesized by condensation reaction with chloroacetone and phenol in the presence of concentrated sulfuric acid, and has been successfully grown by solution growth technique. This is the first report in the literature on the crystallization of DHAMS and exhibited the birefringent melt (liquid crystal property) of the optical properties. FTIR and FTNMR studies are in accordance with the structure. Good quality crystals were grown by slow evaporation technique by acetone as solvent. A transmission spectrum of the crystal was obtained in the region of 285 nm. The structural and optical properties were studied. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
108.
G. Arunmozhi S. Ganesamoorthy C. V. Kannan E. de M. Gomes P. Ramasamy 《Crystal Research and Technology》2005,40(8):773-777
Crystal growth of PZN‐PT single crystals using slow cooling flux technique with PbO flux is reported in this communication. Optimum growth conditions to maximize the amount of perovskite are also suggested. The grown crystals are characterized by dielectric and FIR spectroscopy. Temperature dependence of ε′ very close to the transition temperature shows a first order phase transition. Diffused phase transition and strong frequency dependence of ε′ around transition temperature are also observed. The real part of ε′ was found to obey the relation ε′ – ε∞ = χ′(T‐To)2. Dispersion in the ferroelectric phase is suggested to originate from ordering of domains. Competition in the B‐site occupancy by Zn, Nb and Ti ions is suggested to be the origin for the additional modes in the FIR reflectivity at room temperature. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
109.
110.
Winaki P. Sohtun Themmila Khamrang Arunachalam Kannan Gowdhami Balakrishnan Dhandayutham Saravanan Mohammad Abdulkader Akhbarsha Marappan Velusamy Mallayan Palaniandavar 《应用有机金属化学》2020,34(5):e5593
A series of iron(III) bis-complexes of the type [FeL2]X 1-4 , X = OH− ( 1 ), Cl¯ ( 3 ), and FeCl4¯ ( 2 , 4 ), where LH is a tridentate (N,N,S) ligands such as N′-(1-pyridin-2-ylethylidene)-hydrazinecarbodithioic acid methyl ester ( HL1 ), N′-(phenylpyridin-2-ylmethylene)-hydrazinecarbodithioic acid methyl ester ( HL2 ), N′-quinolin-2-ylmethylene-hydrazinecarbodithioic acid methyl ester ( HL3 ), or N′-(1-methyl-1H-imidazol-2-yl-methylene)hydrazinecarbodithioic acid methyl ester ( HL4 ) has been isolated in moderate to good yields and completely characterized by elemental analyses, conductivity studies, and infrared and UV-visible spectral measurements. The single crystal X-ray structures of 1 , 2 and 4 revealed that two deprotonated tridentate (NNS) ligands are meridionally coordinated to constitute a distorted octahedral coordination geometry around iron(III). In acetonitrile solution, all the complexes show quasi-reversible Fe(III)/Fe(II) redox behavior. The in vitro cytotoxicity of the ligands HL1–HL4 (IC50: HL1 , 64.5; HL2 , 51.0; HL3 , 124.0; HL4 , 45.0 μM at 24 h) and complexes 1–4 (IC50: 1 , 84.5; 2 , 40.0; 3 , 168.5; 4 , 50.5 μM at 24 h) towards A549 lung cancer cell lines are similar to cisplatin (69.0 μM), revealing that free ligands cause cancer cell death with potency higher than the corresponding iron(III) complexes. Also, both the ligands and the complexes cause cell death mainly through apoptotic mode, as revealed by the observation of a higher percentage of apoptotic cells in acridine orange (AO)/ ethidium bromide (EB), and Annexin V-Cy3 stained cancer cells. 相似文献