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21.
We have investigated the output behaviour of a low temperature HyBrID-type copper laser operating with a flowing Ne–HCl reactive
gas mixture. 15.5 W of average power was observed from a 19 mm bore device at 23 kHz PRF corresponding to a specific output
power of 78 mW/cm3. The output power was 20–30% lower than that of the same device operating with an Ne–HBr mixture; however,
it markedly exceeds the output of similar sized elemental copper vapour lasers (with or without hydrogen additive).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
22.
M. D. Ainsworth D. J. W. Brown D. W. Coutts J. A. Piper 《Optical and Quantum Electronics》1991,23(4):S539-S548
The characteristics of high repetition rate CVL devices incorporating passive external heating have been investigated. Pre-heating of the CVL plasma tube using external heating has been shown to significantly reduce CVL warm-up time, while supplementary heating of the CVL plasma tube using external heating allows efficient CVL operation with reduced discharge power input without any degradation in output power. 相似文献
23.
J. Papenberg W. Piper W. Kalke und U. Knobloch 《Fresenius' Journal of Analytical Chemistry》1970,252(2-3):174-178
Zusammenfassung Nach Sepharose 2 B Gelfiltration nimmt die Mobilität der Lipoproteinfraktionen VLDL, LDL und HDL auf Agarose-Gel zu. Albumin macht diesen Effekt rückgängig. Die Möglichkeit der Spontanhydrolyse der Triglyceride der Lipoproteinfraktionen mit Zunahme der freien Fettsäuren und damit auch der elektrischen Ladung wird diskutiert. Der Albumineffekt beruht dann auf einer Bindung dieser freien Fettsäuren.
Abkürzungen VLDL Very Low Density Lipoprotein - LDL Low Density Lipoprotein - HDL High Density Lipoprotein Teilweise unterstützt von der Deutschen Forschungsgemeinschaft. 相似文献
Effect of albumin on the electrophoretic mobility of human serum lipoproteins on agarose gel
The electrophoretic mobility of the VLDL, LDL and HDL fractions increases on agarose gel after Sepharose 2 B gel filtration. This effect is broken of by albumin. The possibility of spontaneous hydrolysis of the triglycerides of the lipoproteins with a successive increase of the free fatty acid content and electric charge is discussed. The albumin effect is based on the binding of these free fatty acids.
Abkürzungen VLDL Very Low Density Lipoprotein - LDL Low Density Lipoprotein - HDL High Density Lipoprotein Teilweise unterstützt von der Deutschen Forschungsgemeinschaft. 相似文献
24.
Directly written monolithic waveguide laser incorporating a distributed feedback waveguide-Bragg grating 总被引:2,自引:0,他引:2
We report the fabrication and performance of the first C-band directly written monolithic waveguide laser (WGL). The WGL device was created in an erbium- and ytterbium-doped phosphate glass host and consisted of an optical waveguide that included a distributed feedback Bragg grating structure. The femtosecond laser direct-write technique was used to create both the waveguide and the waveguide-Bragg grating simultaneously and in a single processing step. The waveguide laser was optically pumped at approximately 980 nm and lased at 1,537 nm with a bandwidth of less than 4 pm. 相似文献
25.
26.
Piper T Mareck U Geyer H Flenker U Thevis M Platen P Schänzer W 《Rapid communications in mass spectrometry : RCM》2008,22(14):2161-2175
The application of a comprehensive gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS)-based method for stable carbon isotopes of endogenous urinary steroids is presented. The key element in sample preparation is the consecutive cleanup with high-performance liquid chromatography (HPLC) of underivatized and acetylated steroids, which allows the isolation of ten analytes (11beta-hydroxyandrosterone, 5alpha-androst-16-en-3beta-ol, pregnanediol, androsterone, etiocholanolone, testosterone, epitestosterone, 5alpha-androstane-3alpha,17beta-diol, 5beta-androstane-3alpha,17beta-diol and dehydroepiandrosterone) from a single urine specimen. These steroids are of particular importance to doping controls as they enable the sensitive and retrospective detection of steroid abuse by athletes.Depending on the biological background, the determination limit for all steroids ranges from 5 to 10 ng/mL for a 10 mL specimen. The method is validated by means of linear mixing models for each steroid, which covers repeatability and reproducibility. Specificity was further demonstrated by gas chromatography/mass spectrometry (GC/MS) for each analyte, and no influence of the sample preparation or the quantity of analyte on carbon isotope ratios was observed. In order to determine naturally occurring (13)C/(12)C ratios of all implemented steroids, a reference population of n = 61 subjects was measured to enable the calculation of reference limits for all relevant steroidal Delta values. 相似文献
27.
M. Ams G.D. Marshall P. Dekker J.A. Piper M.J. Withford 《Laser \u0026amp; Photonics Reviews》2009,3(6):535-544
Direct‐write optical waveguide device fabrication is probably the most widely studied application of femtosecond laser micromachining in transparent dielectrics at the present time. Devices such as buried waveguides, power splitters, couplers, gratings, optical amplifiers and laser oscillators have all been demonstrated. This paper reviews the application of the femtosecond laser direct‐write technique to the fabrication of active waveguide devices in bulk glass materials. 相似文献
28.
White SS Li H Marsh RJ Piper JD Leonczek ND Nicolaou N Bain AJ Ying L Klenerman D 《Journal of the American Chemical Society》2006,128(35):11423-11432
We have studied a donor-acceptor fluorophore-labeled DNA switch where the acceptor is Alexa-647, a carbocyanine dye, in solution at the single molecule level to elucidate the fluorescence switching mechanism. The acceptor, which is in an initial high fluorescence trans state, undergoes a photoisomerization reaction resulting in two additional states during its sub-millisecond transit across the probe volume. These two states are assigned to a nonfluorescent triplet trans state that strongly quenches the donor emission and a singlet cis state that blocks the fluorescence resonance energy transfer (FRET) pathway and gives rise to donor-only fluorescence. The formation of these states is faster than the transit time, so that all three states are approximately equally populated under our experimental conditions. The acceptor dye can stick to the DNA in all these states, with the rate of unsticking determining the rate of isomerization into the other states. Measurement of the rate of change of the FRET signal therefore provides information about the fluorophore-DNA intramolecular dynamics. These results explain the large zero peak in the proximity ratio, often seen in single molecule FRET experiments, and suggest that photoinduced effects may be important in single molecule FRET experiments using carbocyanine dyes. They also suggest that for fast photoinduced switching the interactions of the acceptor dye with the DNA and other surfaces should be prevented. 相似文献
29.
W.J. Marinelli L.G. Piper 《Journal of Quantitative Spectroscopy & Radiative Transfer》1985,34(4):321-330
Improved spectroscopic constants have been used to calculate Rydberg-Klein-Rees (RKR) potentials and Franck-Condon factors for the IF(B3Π0+-X1Σ+) transition. The Franck-Condon factors are generally in good agreement with previously calculated values, but differ by as much as 30% for transitions from higher levels of the B-state. Several experimentally measured relative transition moment functions have been evaluated and the best scaled, so that the total transition probability calculated for each B-state vibrational level, A(v'), matched measured values. The scaled function was then used to calculate individual transition probabilities, A(v',v), for the vibronic transitions. 相似文献
30.
A. Napier J. Schneps T.Y. Chen E.W. Jenkins K-W. Lai J. Le Britton Y.C. Lin A.E. Pifer H.C. Fenker D.R. Green J.R. Albright J.H. Goldman S.L. Hagopian J.E. Lannutti J.E. Piper C.C. Chang T.C. Davis R.N. Diamond W.P. Trower 《Physics letters. [Part B]》1984,149(6):514-518
K1±(892) production is studied in the reaction π?N → KS0KS0 + X where X includes up to five observed charged particles. An excess of K1? over K1+ is observed for Feynman-x > 0.1. The ratio of K1+ to K1? decreases with x as predicted by QCD counting rules. KS0 and K1 production are compared to recent D and D1 data from other experiments. 相似文献