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41.
42.
The higher order contributions to Jacobian in Fujikawa’s path integral framework is considered and the form of anomaly equation
in higher orders is established. An argument for the Adler-Bardeen theorem in this formulation is given. 相似文献
43.
Satish N. Dighe 《Tetrahedron letters》2009,50(45):6139-6142
The synergy of the combined use of DMSO and an ionic liquid viz. (bbim)+Br− has brought about a mild, convenient, efficient, and rapid protocol for the synthesis of 1-substituted-1H-1,2,3,4-tetrazoles via the condensation of amines, triethyl orthoformate, and sodium azide at ambient temperature in excellent isolated yields (85-90%). The inherent Bronsted acidity of ionic liquid and high polarity of both IL and DMSO resulted in a significant enhancement in the reaction rate. 相似文献
44.
N. Chakraborti B. Siva Kumar V. Satish Babu S. Moitra A. Mukhopadhyay 《Applied Mathematical Modelling》2008
A new genetic algorithms based multi-objective optimization algorithm (NMGA) has been developed during study. It works on a neighborhood concept in the functional space, utilizes the ideas on weak dominance and ranking and uses its own procedures for population sizing. The algorithm was successfully tested with some standard test functions, and when applied to a real-life data of the hot-rolling campaign of an integrated steel plant, it outperformed another recently developed multi-objective evolutionary algorithm. 相似文献
45.
Hydrophobic silica aerogels possesses potential applications as insulating materials for refrigerators, furnaces and thermos
flasks. In such applications, aerogel materials may get exposed for longer time to atmosphere and the adsorbed water content
from surroundings may deteriorate its properties. Therefore, hydrophobicity of the arogels becomes crucial parameter and needs
to be evaluated critically. In the present works, silica alcogels were prepared using the mixture of tetramethoxysilane and
methyltrimethoxysilane (MTMS) as precursor chemicals for silica. The concentration of MTMS, which is used as hydrophobic reagent,
in the said mixture of silicon alkoxide was varied between 0 and 100% in steps of 25%. After gelation, the alcogels were dried
supercritically by solvent extraction method. Resulted aerogels were exposed to relative humidity of 90% for a period of one
month which were then characterized to assess hydrophobicity by the contact angle using water drop method and adsorbed water
content measurements by Karl Fischer’s Titration method. Observed contact angle and water content measurements were compared
and the results are reported in the present research paper. 相似文献
46.
Satish Balasaheb Nimse Junghoon Kim Keum-Soo Song Chan-Yong Jung Sudhakara Reddy Seelam 《Tetrahedron letters》2010,51(21):2840-551
We report the new water-soluble aminocalix[4]arene hosts 1 and 2 with deep hydrophobic cavity facilitating hydrophobic mouth and hydrophilic mouth, respectively. The 1H NMR titrations revealed that host 1 shows high selectivity for neutral guests 9 and 10, with log K of 4.2 and 4.6, respectively. The host 2 shows log K of 4.9 for binding with guest 15. Moreover, the binding ability of the host 2 for guest 14 is stronger by a factor of 1000 than that of the host 1. 相似文献
47.
McIntosh JA Robertson CR Agarwal V Nair SK Bulaj GW Schmidt EW 《Journal of the American Chemical Society》2010,132(44):15499-15501
A protease from ribosomal peptide biosynthesis macrocyclizes diverse substrates, including those resembling nonribosomal peptide and hybrid polyketide-peptide products. The proposed mechanism is analogous to thioesterase-catalyzed chemistry, but the substrates are amide bonds rather than thioesters. 相似文献
48.
Excess molar volumes, VE123V^{\mathrm{E}}_{123} of 1,3-dioxolane or 1,4-dioxane (1) + benzene or toluene (2) + formamide or + N,N-dimethylformamide (3) ternary mixtures at 308.15 K and at atmospheric pressure have been determined dilatometrically over
the entire composition range. The excess molar volumes data of these ternary systems were fitted to the Redlich–Kister equation.
The data have been analyzed in terms of Graph theory (model) to understand the nature and strength of molecular interactions
existing in these mixtures. It has been observed that VE123V^{\mathrm{E}}_{123} values predicted by Graph theory compare well with their corresponding experimental values. 相似文献
49.
Bello D Einhorn A Kaushal R Kenchaiah S Raney A Fieno D Narula J Goldberger J Shivkumar K Subacius H Kadish A 《Magnetic resonance imaging》2011,29(1):50-56
Background
Cardiac magnetic resonance imaging (CMR) can accurately determine infarct size. Prior studies using indirect methods to assess infarct size have shown that patients with larger myocardial infarctions have a worse prognosis than those with smaller myocardial infarctions.Objectives
This study assessed the prognostic significance of infarct size determined by CMR.Methods
Cine and contrast CMR were performed in 100 patients with coronary artery disease (CAD) undergoing routine cardiac evaluation. Infarct size was determined by planimetry. We used Cox proportional hazards regression analyses (stepwise forward selection approach) to evaluate the risk of all-cause death associated with traditional cardiovascular risk factors, symptoms of heart failure, medication use, left ventricular ejection fraction, left ventricular mass, angiographic severity of CAD and extent of infarct size determined by CMR.Results
Ninety-one patients had evidence of myocardial infarction by CMR. Mean follow-up was 4.8±1.6 years after CMR, during which time 30 patients died. The significant multivariable predictors of all-cause mortality were extent of myocardial infarction by CMR, extent of left ventricular systolic dysfunction, symptoms of heart failure, and diabetes mellitus (P<.05). The presence of infarct greater than or equal to 24% of left ventricular mass and left ventricular ejection fraction less than or equal to 30% were the most optimal cut-off points for the prediction of death with bivariate adjusted hazard ratios of 2.11 (95% confidence interval 1.02-4.38) and 4.06 (95% confidence interval 1.73-9.54), respectively.Conclusions
The extent of myocardial infarction determined by CMR is an independent predictor of death in patients with CAD. 相似文献50.
Satish Balasaheb Nimse Junghoon Kim Van-Thuan Nguyen Chan-Yong Jung Taisun Kim 《Tetrahedron letters》2010,51(47):6156-6160
The pH of a solution shows a significant effect on the dynamics of the gate (formed by eight benzylic functions) and portal on the hydrophobic cavity of receptor. At pH 5.8 the gate closes and prohibits the entry of anionic guests. However, at pH 7.3 the gate opens and allows the entry of anionic guests into the hydrophobic cavity. It is the first time that anionic receptor efficiently recognizes anionic guests. 相似文献