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461.
Muralidharan Selvadurai Meyyanathan Subramania Nainar Muruganantham Nithyanantham Rajan Sekar Krishnaraj Kaliaperumal Suresh Bhojraj 《平面色谱法杂志一现代薄层色谱法》2009,22(3):207-210
JPC – Journal of Planar Chromatography – Modern TLC - A simple, sensitive, precise, and rapid high-performance thin-layer chromatographic (HPTLC) method for analysis of dexibuprofen in... 相似文献
462.
463.
Adsorption properties of CO molecule on NiO nanocone were investigated using density functional approach in terms of adsorbed energy, structural, and electronic properties. The results of the present study reveal that the favorable adsorption site for CO molecule is to the oxygen atom on the apex of NiO nanocone. The adsorbed energy on the apex of oxygen atom in nanocone is found to be ?8.432 eV. The average variation in the energy gap is found to be 50 % for CO adsorption on apex of oxygen atom. The Mulliken population analysis and density of states also confirm the adsorption of CO on to the oxygen atom in the apex of nanocone. The present result provides the insight to fine-tune the sensing properties of CO on to the NiO nanocone and enhance the sensing properties. 相似文献
464.
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A Convenient One‐Pot Synthesis of Triazolopyridine and Related Heterocycle Fused‐Triazole Analogs Through Copper Catalyzed Oxidative Cyclization Strategy
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R. Srinivasan J. Sembian Ruso N. S. Nagarajan R. Senthil Kumaran G. Manickam 《Journal of heterocyclic chemistry》2016,53(2):606-614
One‐pot synthesis of heterocycle fused‐triazole analogs from the corresponding aldehydes and heteroarylhydrazines is demonstrated. Transformation of hydrazones to the desired systems was achieved by employing the oxidative cyclization with catalytic CuBr2 and oxone. This reaction condition is mild and selective, and a wide range of functional groups were able to sustain. An array of biologically important triazolopyridines, triazolopyridazines, triazolopyrimidines, and triazoloquinolines were obtained in fairly good yield. 相似文献
466.
S. S. Saravanakumar A. Kumaravel T. Nagarajan I. Ganesh Moorthy 《International Journal of Polymer Analysis and Characterization》2014,19(5):383-390
Incompatibility between hydrophilic natural fibers and hydrophobic matrix is known to affect the adhesion of the fiber and matrix. Therefore, it becomes necessary to modify the surface of natural fibers for improved adhesion between the fiber and matrix. Prosopis juliflora fibers (PJFs) are known to possess desirable properties for use as reinforcement in polymer matrices. Using chemical analysis, the optimal condition for alkali treatment of the PJFs was found to be 5% (w/v) of NaOH concentration with 60 min soaking time. Chemical modifications favorably changed the physiochemical properties of PJFs and undoubtedly diminished the amorphous and wax contents. 相似文献
467.
Murugan Sathishkumar Poovan Shanmugavelan Sangaraiah Nagarajan Murugesan Maheswari Murugan Dinesh Alagusundaram Ponnuswamy 《Tetrahedron letters》2011,52(22):2830-2833
A solvent-free synthesis of amides via the coupling of phosphazenes with carboxylic acids is reported. Increasing the rate of heating either by microwave irradiation or conventional heating results in multifold increase in the rate of amide bond formation. Synthesis of a library of amides including a potent antitumour candidate has been accomplished. 相似文献
468.
Development and validation of a HPLC‐PDA bioanalytical method for the simultaneous estimation of Aliskiren and Amlodipine in human plasma
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Sai Sandeep Mannemala Janaki Sankarachari Krishnan Nagarajan 《Biomedical chromatography : BMC》2015,29(3):346-352
A simple, unique and selective HPLC‐PDA method was developed and validated for the simultaneous estimation of aliskiren (ALS) and amlodipine (AML) in human plasma. Extraction of the sample was accomplished by protein precipitation. Plasma proteins were precipitated by employing acetonitrile containing hydrochlorothiazide as internal standard. The compounds were analyzed by HPLC by using PDA detector on a Hibar C18 (250 × 4.6 mm) column with a mobile phase comprising acetonitrile and phosphate buffer (pH 4.2 and 25 mm ; 60:40 v/v) with a flow rate of 0.8 mL/min. Different sample pretreatment techniques were evaluated but protein precipitation was found to be satisfactory, offering good recovery values of 97.11–98.45% for ALS and 97.5–99.12% for AML. The within‐day precisions for ALS were 96.66, 99.16 and 99.41% at 90, 240 and 480 ng/mL, respectively, and for AML they were 97.27, 99.54 and 99.31% at 3.3, 8.8 and 17.6 ng/mL, respectively. The between‐day precisions for ALS were 96.66, 99.16 and 99.41% at 90, 240 and 480 ng/mL, respectively and the between‐day precisions for AML were 98.18, 99.20 and 99.40% at 3.3, 8.8 and 17.6 ng/mL, respectively. The limit of quantitation was 30 and 1.0 ng/mL for ALS and AML respectively. Different constituents of plasma proteins did not interfere with the absolute recovery of ALS and AML. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
469.
Hemavathy Nagarajan Umashankar Vetrivel 《Journal of computer-aided molecular design》2018,32(8):821-840
Heparanase (HPSE) is an endo-β-d-glucuronidase that has diverse functions in mammals which includes cell survival, cell adhesion and cell migration. HPSE features both enzymatic and non-enzymatic functionalities in a pH dependent manner. Hence, in this study, an extensive molecular dynamics simulation, molecular docking, protein Angular dispersion analysis were performed for apo form and holo forms to understand its conformational changes at varied pH conditions. On comparative conformational analysis of apo and holo forms, it was inferred that the HSPE has undergone pH dependent structural changes, thereby affecting the binding of Heparan sulfate proteoglycan (HSPG). Moreover, HPSE also showed favourable structural changes for optimal binding of HSPG at pH 5.0 and 6.0, as inferred from functional flap displacements within HPSE. Thus, this study provides significant insights on optimal pH for HPSE to exhibit its enzymatic activity. The outcome of this study shall aid in ideal lead generation for targeting HPSE mediated disease conditions. 相似文献
470.
Carbene in Cupredoxin Protein Scaffolds: Replacement of a Histidine Ligand in the Active Site Substantially Alters Copper Redox Properties
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Dr. Matteo Planchestainer Dr. Nathalie Segaud Dr. Muralidharan Shanmugam Prof. Jonathan McMaster Prof. Francesca Paradisi Prof. Martin Albrecht 《Angewandte Chemie (International ed. in English)》2018,57(33):10677-10682
N‐heterocyclic carbene (NHC) ligands have had a major impact in homogeneous catalysis, however, their potential role in biological systems is essentially unexplored. We replaced a copper‐coordinating histidine (His) in the active site of the redox enzyme azurin with exogenous dimethyl imidazolylidene. This NHC rapidly restores the type‐1 Cu center, with spectroscopic properties (EPR, UV/Vis) that are identical to those from N‐coordination of the His in the wild type. However, the introduction of the NHC markedly alters the redox potential of the metal, which is a key functionality of this blue copper protein. These results suggest that C‐bonding for histidine is plausible and a potentially relevant bonding mode of redox‐active metalloenzymes in their (transient) active states. 相似文献