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11.
Veronika Gemmer-Colos und Rolf Neeb 《Fresenius' Journal of Analytical Chemistry》1978,293(4):290-294
Zusammenfassung Kleine Mengen Ni, Cu und Zn in wäßrigen Lösungen können nach Ausschütteln ihrer Dipropyldithiocarbamatochelate gas-chromatographisch bestimmt werden. Arbeitsbedingungen für den 0,01–1 ppm-Bereich werden angegeben. Die Reproduzierbarkeit der Bestimmung wird durch Zusatz eines inneren Standards verbessert.
Dialkyldithiocarbamates as reagents for the gas-chromatographic determination of metalsII. Determination of zinc, copper and nickel as dipropyldithiocarbamato chelates after extraction from aqueous solution
Summary Small amounts of Ni, Cu and Zn in aqueous solutions can be determined by gas chromatography after extraction of their dipropyldithiocarbamatochelates. Working details for the 0.01–1 ppm range are reported. Reproducibility is markedly improved by addition of an inner standard.
Die Untersuchungen wurden in dankenswerter Weise durch Mittel der Deutschen Forschungsgemeinschaft und des Verbands der chemischen Industrie unterstützt. 相似文献
12.
R. C. Milward 《Fresenius' Journal of Analytical Chemistry》1973,264(3):195-199
Summary This article describes a new commercial Far-Infrared Fourier Spectrometer system which has been developed for routine spectroscopy in the 10–1000 cm–1 spectral region. The instrument incorporates real-time data processing and has been automated wherever possible for foolproof operation. A versatile sample chamber allows a wide range of spectroscopic studies to be performed, on solids, liquids and gases over a wide range of temperatures. A number of spectra are presented to illustrate the performance and typical applications of this Fourier spectrometer.
Ein neues fourier-spektrometer für das ferne infrarot
Zusammenfassung Nach einer kurzen Einführung in die Methode der Fourier-Spektroskopie wird ein neues kommerzielles Fern-Infrarot-Fourier-Spektrometer mit real-time Datenverarbeitungsanlage beschrieben. Das Gerät ist für die Spektroskopie im Bereich 10–1000 cm–1 konstruiert und weitgehend automatisiert. Eine vielseitig verwendbare Probenkammer ermöglicht umfangreiche spektroskopische Untersuchungen von Festkörpern, Flüssigkeiten und Gasen in einem sehr großen Temperaturbereich. Anhand einer Reihe von Spektren werden Leistung und typische Anwendungen dieses Fourier-Spektrometers erläutert.
Lecture presented at Euroanalysis I Conference, 28. 8.–1. 9. 1972 in Heidelberg, Germany. 相似文献
13.
Evert J. Ditzel Xavier L. R. Fontaine Norman N. Greenwood John D. Kennedy Mark Thornton-Pett 《无机化学与普通化学杂志》1992,616(10):79-85
The action of SMe2 on the ten-vertex nido-ruthenaborane [6-(η6-C6Me6)RuB9Hl3] ( 1 ) provides a high-yield route to the unsubstituted isocloso-ruthenaborane [1-(η6-C6Me6)RuB9H9] (2). The benzene analogue [1-(η6-C6Me6)RuB9H9] is prepared similarly. By contrast, reaction of (1) with PhNH2 gives a variety of B-phenylamino isocloso derivatives, including orange crystals of [1-(η6-C6Me6)-2-(PhNH)-isocloso-1-RuB 9 H8] ( 3 ), red-orange [1-(η6-C6Me6)-2,3-(PhNH)2-isocloso-1-RuB9H7] ( 4 ) and dark-red [1-(η6-C6Me6)-5,6,7-(PhNH)3-isocloso-1-RuB9H6] ( 5 ). Detailed 1H and 11B nmr properties of these various compounds are described. The structure of ( 3 ) has been established by a single-crystal X-ray diffraction study of the solvate [1-(η6-C6Me6)-2-(PhNH)-isocloso-1-RuB9H8] · 1/2 CH2Cl2; the crystals were monoclinic, space group C2/c, with a = 1895.1(3), b = 1556.6(3), c = 1716.4(3) pm, β = 104.37(1)° and z = 8. 相似文献
14.
Norman G. Anderson 《Fresenius' Journal of Analytical Chemistry》1972,261(4-5):257-271
Summary New instrumentation has been developed at ORNL for analyzing physiologic specimens. The system is designed for use in clinical laboratories, hospitals, and emergency rooms and for use by researchers. Miniaturized versions may also be used in prolonged space flights.After consideration of ease of automation, flexibility, and rapid startup, multiple analyses performed in parallel was chosen as the desired approach. Concepts employed in developing the system are discussed, including:(1) dynamic mixing of samples and reagents through centrifugal transfer from transfer disks into cuvets; (2) rotor design allowing emptying, flushing, and drying of cuvets; (3) precise temperature control; (4) spectrophotometric reaction monitoring; (5) data reduction, with all data stored for possible recall; (6) feedback control for error correction and time saving. Possible future improvements are indicated.
Entwicklung schneller Analysatoren
Zusammenfassung Im Oak Ridge National Laboratory wurde ein neues Analysatorsystem entwickelt, das für die Analyse physiologischer Proben bestimmt ist und in klinischen Laboratorien, Krankenhäusern, Unfallstationen, Forschungsinstituten sowie in einer verkleinerten Version auch in der Raumfahrt zum Einsatz gelangen kann.Das System zeichnet sich aus durch leichte Automatisierbarkeit, Flexibilität, rasche Inbetriebnahme und eignet sich für parallel durchgeführte Serienanalysen. Die folgenden Charakteristica des Systems werden diskutiert: 1. Dynamisches Mischen von Proben und Reagentien durch zentrifugale Übertragung in die Küvetten, 2. Entleeren, Spülen und Trocknen der Küvetten durch Rotation, 3. Genaue Temperaturkontrolle, 4. Spektrophotometrische Reaktionsüberwachung, 5. Datenberechnung mit Speicherung aller Werte für möglichen Abruf, 6. Feedback-Kontrolle zur Fehlerkorrektur und Zeiteinsparung. Mögliche zukünftige Verbesserungen werden erwähnt.
Operated for the U.S. Atomic Energy Commission by the Nuclear Division of Union Carbide Corporation. 相似文献
15.
16.
W Schoner 《Angewandte Chemie (International ed. in English)》1971,10(12):882-889
The transport of Na+ out of the cell and K+ into the cell against a concentration gradient is catalyzed by a (Na+ + K+)-activated ATPase. The way in which the cations pass through the cell membrane has not yet been elucidated. Studies on the ATP hydrolysis revealed a Na+-dependent phosphorylation of the enzyme protein; the conformation of the enzyme also appears to change. The energy required for transport of the cations against their concentration gradients is probably provided by K+-dependent hydrolysis of the enzyme-bound phosphate. The enzyme can synthesize ATP from inorganic phosphate and ADP on reversal of the cation concentration gradient. By keeping the enzyme in a particular conformation, the cardiac glycoside ouabain specifically inhibits the Na+ pump. 相似文献
17.
The effect of laser irradiation on the optical properties of thermally evaporated Se100?x Te x (x=8, 12, 16) chalcogenide thin films has been studied. The result shows that the irradiation causes a shift in the optical gap. The results have been analyzed on the basis of laser irradiation-induced defects in the film. The width of the tail of localized state in the band gap has been evaluated using the Urbach edge method. As the irradiation time increases, the values of the optical energy gap for all compositions decrease, while tail energy width increases. It is also observed that the optical energy gap decreases with increasing Te content in the alloy. These changes are a consequence of an increment in disorder produced by laser irradiation in the amorphous structure of thin film. 相似文献
18.
Dr. Carlo Fasting Prof. Christoph A. Schalley Dr. Marcus Weber Prof. Oliver Seitz Prof. Stefan Hecht Prof. Beate Koksch Dr. Jens Dernedde Prof. Christina Graf Prof. Ernst‐Walter Knapp Prof. Rainer Haag 《Angewandte Chemie (International ed. in English)》2012,51(42):10472-10498
Multivalent interactions can be applied universally for a targeted strengthening of an interaction between different interfaces or molecules. The binding partners form cooperative, multiple receptor–ligand interactions that are based on individually weak, noncovalent bonds and are thus generally reversible. Hence, multi‐ and polyvalent interactions play a decisive role in biological systems for recognition, adhesion, and signal processes. The scientific and practical realization of this principle will be demonstrated by the development of simple artificial and theoretical models, from natural systems to functional, application‐oriented systems. In a systematic review of scaffold architectures, the underlying effects and control options will be demonstrated, and suggestions will be given for designing effective multivalent binding systems, as well as for polyvalent therapeutics. 相似文献
19.
Ricardo García-Pelayo Iván Salazar William C. Schieve 《Journal of statistical physics》1993,72(1-2):167-187
An analytically solvable model for sand avalanches of noninteracting grains of sand, based on the Chapman-Kolmogorov equations, is presented. For a single avalanche, distributions of lifetimes, sizes of overflows and avalanches, and correlation functions are calculated. Some of these are exponentials, some are power laws. Spatially homogeneous distributions of avalanches are also studied. Computer simulations of avalanches of interacting grains of sand are compared to the solutions to the Chapman-Kolmogorov equations. We find that within the range of parameters explored in the simulation, the approximation of noninteracting grains of sand is a good one. 相似文献
20.
D. Valenti L. Schimansky-Geier X. Sailer B. Spagnolo 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,50(1-2):199-203
The dynamics of a spatially extended system of two competing
species in the presence of two noise sources is studied. A
correlated dichotomous noise acts on the interaction parameter and
a multiplicative white noise affects directly the dynamics of the
two species. To describe the spatial distribution of the species
we use a model based on Lotka-Volterra (LV) equations. By writing
them in a mean field form, the corresponding moment equations for
the species concentrations are obtained in Gaussian approximation.
In this formalism the system dynamics is analyzed for different
values of the multiplicative noise intensity. Finally by comparing
these results with those obtained by direct simulations of the
time discrete version of LV equations, that is coupled map lattice
(CML) model, we conclude that the anticorrelated oscillations of
the species densities are strictly related to non-overlapping
spatial patterns. 相似文献