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21.
Nanoparticles coated with single stranded DNA have been shown to efficiently hybridize to targets of complementary DNA. This property might be used to implement programmable (or algorithmic) self-assembly to build nanoparticle structures. However, we argue that a DNA coated nanoparticle by itself cannot be used as a programmable self-assembly building block since it does not have directed bonds. A general scheme for assembling and purifying nanoparticle eight-mers with eight geometrically well-directed bonds is presented together with some preliminary experimental work.  相似文献   
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Bisquinones 16 – 20 , in which the quinoid moieties are tethered by 2-6 methylene units, have been synthesized via the bis(dimethoxybenzenes) 2 , 6 , 9 , 14 , and 15 . Compounds 16 – 20 were transformed into the corresponding bis(DCNQIs) 21 – 25 using standard procedures. Interactions between the two quinoid units, which fade with the length of the tethering chain, have been observed by 13C-NMR spectroscopy, backed by calculated charge densities (Table 1) and by their cyclovoltammograms which indicate two independent two-step electron transfers. Similar results arise from ESR investigations of the bis(quinone) radical ions. All DCNQIs 21 – 25 form charge-transfer complexes with TTF and copper radical anion salts with reasonable powder conductivities. Since single crystals could not be grown, the structure of these materials remains unknown.  相似文献   
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Summary An incomplete U-statistic is obtained by sampling the terms of an U-statistic. This paper derives the asymptotic distribution (if the variance is finite). Depending on the number of sampled terms, the resulting distribution is either the same as for the U-statistic, a normal distribution, or something intermediate. Also the case of a non-random sampling of the terms is treated. As an example, a non-parametric test of the independence of two circular random variables is studied. The results are generalized to generalized U-statistics.  相似文献   
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We consider branching processes consisting of particles (individuals) of two types (type L and type S) in which only particles of type L have offspring, proving estimates for the survival probability and the (tail of) the distribution of the total number of particles. Such processes are in some sense closer to single- than to multi-type branching processes. Nonetheless, the second, barren, type complicates the analysis significantly. The results proved here (about point and survival probabilities) are a key ingredient in the analysis of bounded-size Achlioptas processes in a recent paper by the last two authors.  相似文献   
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Methodological aspects of the determination of 11C/14C kinetic isotope effects (KIEs) were investigated using the reaction of N, N-dimethyl-p-toluidine with labelled methyl iodide in methanol at 30 °C as model system. The primary 11C KIE was determined to be 1.202 ± 0.008 for this reaction. The isotope effect was determined by a one-pot technique based on liquid chromatographic fractionation of the reactant and product followed by liquid scintillation counting of the 11C and 14C radioactivity in these fractions. The KIE value obtained agrees well with the value predicted from a previously determined 12C/14 C-KIE for the same reaction. Theoretical model calculations of both carbon KIEs were performed using the BEBOVIB IV program. Transition-state models ranging from reactant- to product-like were employed in the calculations, and three different reaction coordinate models with more or less pronounced Walden inversion of the methyl hydrogens were investigated.  相似文献   
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The purpose of this study was to develop an analysis system for studying the relationship between vocal fold vibration and the associated transglottal airflow. Recordings of airflow, electroglottography (EGG), oral air pressure, and acoustic signals were performed simultaneously with high-speed imaging at a rate of approximately 1900 frames/s. Inverse filtered airflow is compared with the simultaneous glottal area extracted from the high-speed image sequence. The accuracy of the synchronization between the camera images and the foot pedal synchronization pulse was examined, showing that potential synchronization errors increase with time distance to the synchronization pulse. Therefore, analysis was limited to material near the synchronization pulse. Results corroborate previous predictions that air flow lags behind area, but also they reveal that relationships between these two entities may be complex and apparently varying with phonation mode.  相似文献   
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A novel, rapid and sensitive liquid chromatography tandem–mass spectrometry method for quantification of vemurafenib in human plasma, that also for the first time allows for metabolite semi‐quantification, was developed and validated to support clinical trials and therapeutic drug monitoring. Vemurafenib was analysed by precipitation with methanol followed by a 1.9 min isocratic liquid chromatography tandem masspectrometry analysis using an Acquity BEH C18 column with methanol and formic acid using isotope labelled internal standards. Analytes were detected in multireaction monitoring mode on a Xevo TQ. Semi‐quantification of vemurafenib metabolites was performed using the same analytical system and sample preparation with gradient elution. The vemurafenib method was successfully validated in the range 0.5–100 μg/mL according to international guidelines. The metabolite method was partially validated owing to the lack of commercially available reference materials. For the first time concentration levels at steady state for melanoma patients treated with vemurafenib is presented. The low abundance of vemurafenib metabolites suggests that they lack clinical significance. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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We study the largest component of a random (multi)graph on n vertices with a given degree sequence. We let n. Then, under some regularity conditions on the degree sequences, we give conditions on the asymptotic shape of the degree sequence that imply that with high probability all the components are small, and other conditions that imply that with high probability there is a giant component and the sizes of its vertex and edge sets satisfy a law of large numbers; under suitable assumptions these are the only two possibilities. In particular, we recover the results by Molloy and Reed on the size of the largest component in a random graph with a given degree sequence. We further obtain a new sharp result for the giant component just above the threshold, generalizing the case of G(n,p) with np = 1 + ω(n)n?1/3, where ω(n) → arbitrarily slowly. Our method is based on the properties of empirical distributions of independent random variables, and leads to simple proofs. © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2009  相似文献   
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