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51.
Amir Averbuch Valery Zheludev Pekka Neittaanmäki Pekka Wartiainen Kari Huoman Kim Janson 《Applied Acoustics》2011,(1):22-34
We present a robust algorithm to detect the arrival of a boat of a certain type when other background noises are present. It is done via the analysis of its acoustic signature against an existing database of recorded and processed acoustic signals. We characterize the signals by the distribution of their energies among blocks of wavelet packet coefficients. To derive the acoustic signature of the boat of interest, we use the Best Discriminant Basis method. The decision is made by combining the answers from the Linear Discriminant Analysis (LDA) classifier and from the Classification and Regression Trees (CART) that is also accompanied with an additional unit, called Aisles, that reduces false alarms rate. The proposed algorithm is a generic solution for process control that is based on a learning phase (training) followed by an automatic real time detection while minimizing the false alarms rate. 相似文献
52.
Audio-frequency wave-guide models for antisymmetric dynamic stiffness of arbitrary long elastomer cylinders are presented. The locally non-mixed boundary conditions at the lateral and radial surfaces are simultaneously satisfied by using the modes corresponding to the dispersion relation for axial waves in cylinders satisfying the stress free boundary conditions at the curved radial boundaries, while the displacement conditions on the flat cylinder ends are satisfied by mode matching. The elastomer is modelled as nearly incompressible with deviatoric visco-elasticity based on a fractional derivative, standard linear solid embodying a Mittag-Leffler relaxation kernel, the main advantage being the minimum parameter number required to successfully model the material properties over a broad frequency band. The stiffness is found to depend strongly on frequency; displaying resonances and anti-resonances. The method is compared with and verified against finite element models. In addition, comparison to thin beam theories, i.e. Euler and Timoschenko theory and a simple shear model, is presented, illustrating the limitations of these models. 相似文献
53.
V.S. Kolhinen T. EronenD. Gorelov J. HakalaA. Jokinen A. KankainenJ. Rissanen J. SuhonenJ. Äystö 《Physics letters. [Part B]》2011
The double-electron-capture Q value for the 136Ce decay to 136Ba has been determined at JYFLTRAP. The measured value 2378.53(27) keV excludes the energy degeneracy with the 0+ excited state of the decay daughter 136Ba at 2315.32(7) keV in a resonant 0νECEC decay by 11.67 keV. The new Q value differs from the old adopted value 2419(13) keV (Atomic Mass Evaluation 2003) by 40 keV and is 50 times more precise. Our calculations show that the precise Q value renders the resonant 0νECEC decay of 136Ce undetectable by the future underground detectors. We measured also the double-β decay Q value of 136Xe to be 2457.86(48) keV which agrees well with the value 2457.83(37) keV measured at the Florida State University. 相似文献
54.
55.
Erick Kindt Sandra Bak Mueller Christine Castle Carine M. Boustany‐Kari 《Biomedical chromatography : BMC》2010,24(7):752-758
Biomarkers are an increasingly important constituent of the drug development process, offering the potential of increased efficiency through reduced compound attrition and earlier proof of mechanism and/or efficacy. Assays developed for compound screening that can be directly translated for clinical trials are especially valuable, but their successful adoption requires a careful balance between assay performance and implementation costs. One such ‘fit‐for‐purpose’ biomarker assay, the indirect measurement of pharmacological modulation of sphingolipid biosynthesis and disposition, is presented here. Among spingolipids, numerous ceramide species are readily detectable in different lipoprotein fractions of mammalian plasma, but their parallel quantification can be prohibitively expensive and time consuming. Ceramides differ in their fatty acid moiety, which is readily removed by hydrolysis, yielding a common sphingosine derivative, the measurement of which serves as an indicator of total ceramide. When followed by liquid chromatography tandem mass spectrometry (LC/MS/MS) for detection, robust analyte quantification becomes relatively straightforward. The practical utility of a method developed to be fit for the purpose of rapidly and quantitatively measuring treatment‐induced variations in total ceramide from hamster plasma and individual lipoprotein fractions is described. With a linear calibration range from 0.003 to 33.4 μm sphingosine, precision and accuracy error in plasma‐based quality controls spiked with ceramides was less than 15%. The specificity of the assay for ceramides was also assessed. The simplicity of the method would allow for its potential translation to other preclinical species, as well as for clinical applications in later‐stage drug development. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
56.
Kari Eloranta 《Journal of statistical physics》1994,76(5-6):1377-1398
We investigate the dynamics of ensembles of diffusive defects in one-dimensional deterministic cellular automata. The work builds on earlier results on individual random walks in cellular automata. Here we give a natural condition guaranteeing diffusive behavior also in the presence of other defects. Simple branching and birth mechanisms are introduced and prototype classes of cellular automata exhibiting weakly interacting walks capable of annihilation and coalescence are studied. Their equilibrium behavior is also characterized. The design principles of cellular automata with desired diffusive interaction properties become transparent from this analysis. 相似文献
57.
58.
Dr. Ngong Kodiah Beyeh Dr. Fangfang Pan Acad. Prof. Kari Rissanen 《Angewandte Chemie (International ed. in English)》2015,54(25):7303-7307
Iodine (I2) acts as a bifunctional halogen‐bond donor connecting two macrocyclic molecules of the bowl‐shaped halogen‐bond acceptor, N‐cyclohexyl ammonium resorcinarene chloride 1 , to form the dimeric capsule [(1,4‐dioxane)3@ 1 2(I2)2]. The dimeric capsule is constructed solely through halogen bonds and has a single cavity (V=511 Å3) large enough to encapsulate three 1,4‐dioxane guest molecules. 相似文献
59.
Mark Maric Wilhelm van Bronswijk Kari Pitts Simon W. Lewis 《Journal of Raman spectroscopy : JRS》2016,47(8):948-955
The clear coats from a collection of automotive paint samples of 139 vehicles, covering a range of Australian and international vehicle manufacturers and sold in Western Australia, were characterised using FT‐Raman spectroscopy. Principal component analysis (PCA) revealed 19 distinct classes that were associated with the vehicles' manufacturer and model, and in the case of Australian manufacturers, the years of manufacture. Linear discriminant analysis based on the PCA groupings gave excellent discrimination between the groups with 96.9% of the calibration set and 97.6% of the validation set being correctly classified. Although the sample set comprised only vehicles available in Australia, the methodology used is universal and hence applicable in any jurisdiction that is willing and able to generate a statistically significant data set and maintain and update it as new vehicles appear on the market. A FT‐Raman spectroscopy‐based database would rapidly provide information regarding vehicle origin and manufacture and hence generate investigative leads for questioned paint samples found at incident sites. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
60.
Parshintsev J Ruiz-Jimenez J Petäjä T Hartonen K Kulmala M Riekkola ML 《Analytical and bioanalytical chemistry》2011,400(10):3527-3535
In this research, the two most common filter media, quartz and Teflon, were tested to obtain information about the possible
adsorption of gas-phase compounds onto filters during long sample collection of atmospheric aerosols. Particles of nanometer-size
for off-line chemical characterization were collected using a recently introduced differential mobility analyzer for size
separation. Samples were collected at an urban site (Helsinki, SMEARIII station) during spring 2010. Sampling time was 4 to
10 days for particles 50, 40, or 30 nm in diameter. Sample air flow was 4 L/min. The sampling setup was arranged so that two
samples were obtained for each sampling period almost simultaneously: one containing particles and adsorbed gas-phase compounds
and one containing adsorbed gas-phase compounds only. Filters were extracted and analyzed for the presence of selected carboxylic
acids, polyols, nitrogen-containing compounds, and aldehydes. The results showed that, in quartz filter samples, gas-phase
adsorption may be responsible for as much as 100% of some compound masses. Whether quartz or Teflon, simultaneous collection
of gas-phase zero samples is essential during the whole sampling period. The dependence of the adsorption of gas-phase compounds
on vapor pressure and the effect of adsorption on the deposited aerosol layer are discussed. 相似文献