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991.
Probing the response of soft materials at small scales requires examining fundamental behaviors that are often distinct from large-scale interactions. In the development of micrometer- and nanometer-sized holes in soft materials, understanding failure modes becomes essential. We observe fracture behavior in a soft material through a novel method, which leads to the fabrication of small-scale holes in polydimethylsiloxane. We utilize an ultra-sharp tungsten needle to drill this soft elastomeric polymer; this results in controlled hole size and exhibits fracture characteristics observed in brittle materials at larger length scales. We also examine the macroscopic characteristics known to contribute to brittleness and hardness for this material’s response with respect to curing times. This understanding will contribute to many applications including the development of porous materials and DNA sequencing efforts. PACS 81.05.Lg; 81.40.Np; 82.35.Lr 相似文献
992.
Methods for calculating the total and differential cross sections for the production of Ωscb baryons in photon-photon collisions and the results of respective calculations are described. 相似文献
993.
Yu. N. Zakharov S. I. Raevskaya V. Z. Borodin V. G. Kuznetsov I. P. Raevskiĭ 《Physics of the Solid State》2006,48(6):1077-1078
The magnitudes of the temperature hysteresis and diffuse dielectric anomaly corresponding to the transition from the antiferroelectric phase to the ferroelectric phase in PbZr1 ? x TixO3 (0.03 ≤ x ≤ 0.05) ceramics can be reversibly changed by varying the temperatures of heating and cooling in the course of thermocycling. The results obtained indicate that the antiferroelectric-ferroelectric transition in the PbZr1 ? x TixO3 ceramics materials is a smeared first-order phase transition. 相似文献
994.
A. I. Burkhanov P. V. Bondarenko S. I. Raevskaya A. V. Shil’nikov I. P. Raevskiĭ 《Physics of the Solid State》2006,48(6):1114-1116
The dielectric properties of a ceramic and a single crystal of the same composition 0.9NaNbO3-0.1Gd1/3NbO3 (NNG10) with different prehistories of the material are investigated in the low-and infralow-frequency ranges. It is revealed that the dielectric aging of the material based on the NaNbO3 antiferroelectric with a smeared phase transition differs in character from similar phenomena observed in relaxor ferroelectrics. 相似文献
995.
996.
This paper overviews the electro-optical and thermal performances of different types of infrared detectors manufactured by
Sofradir. The detector’s fabrication processes and detector’s performance are shortly described. New staring arrays are more
compact and offer system solutions required by infrared market. Special attention is directed to some reliability advantages
of new dewar design. Finally, the development trends for highest resolution infrared detector are discussed.
The paper presented there appears in Infrared Photoelectronics, edited by Antoni Rogalski, Eustace L. Dereniak, Fiodor F. Sizov, Proc. SPIE Vol. 5957, 59570U (2005). 相似文献
997.
Ph. Laurent M. Abgrall Ch. Jentsch P. Lemonde G. Santarelli A. Clairon I. Maksimovic S. Bize Ch. Salomon D. Blonde J.F. Vega O. Grosjean F. Picard M. Saccoccio M. Chaubet N. Ladiette L. Guillet I. Zenone Ch. Delaroche Ch. Sirmain 《Applied physics. B, Lasers and optics》2006,84(4):683-690
In this paper we describe the cold atom clock PHARAO, designed for microgravity operation. All elements of the PHARAO engineering model have been manufactured and delivered to CNES, the French space agency. We present the clock design, its main characteristics, and initial science operation. PHARAO is one of the main components of the Atomic Clock Ensemble in Space payload that is scheduled to fly on board the International Space Station in 2010. PACS 07.87.+v; 06.30.Ft; 95.55.Sh; 32.80.Pj 相似文献
998.
Summary A non-destructive method is described for the determination of major and minor constituents in archeological specimens by energy-dispersive X-ray fluorescence. Homogeneity tests are made by measuring at various sites of the specimen. In the same way, mean values are obtained for inhomogeneous specimen without taking samples. For calibration, powder standards are used. In case of the determination of elements with numbers up to 14 (Si) a vacuum chamber is used and the dimensions of the specimens are limited by the dimensions of that vacuum chamber, whereas for the determination of elements from K up to U specimens of any size, form or weight are suitable.
Zerstörungsfreie Analyse von archäologischen Proben mit Hilfe der Energie-dispersiven Röntgenfluorescenzanalyse
Zusammenfassung Eine zerstörungsfreie Methode für die Bestimmung von Haupt- und Nebenbestandteilen in archäologischen Proben mit Hilfe der Energie-dispersiven Röntgenfluorescenzanalyse wird beschrieben. Für Homogenitätstests wird an mehreren Stellen der Probe gemessen. In der gleichen Weise werden für inhomogene Proben Mittelwerte erhalten ohne Probenahme. Für die Eichung werden Pulverstandards verwendet. Im Falle der Bestimmung von Elementen mit Ordnungszahlen bis 14 (Si) wird eine Vakuumkammer eingesetzt, und die Dimensionen der Proben sind durch die Dimensionen dieser Vakuumkammer begrenzt, während für die Bestimmung der Elemente K bis U Proben jeder Größe, jeder Form oder jeden Gewichts verwendbar sind.相似文献
999.
1000.
P. D. Morley 《Nuclear Physics A》1987,470(3-4):547-557
We compute delta electroproduction in nuclei using a relativistic nuclear model. Iron is predicted to have the largest per nucleon cross section and narrowest width, but the variation in A is no larger than an 18% effect. Predictions are made for the SLAC NPAS NE5 experiment and a recently completed Bates laboratory experiment. 相似文献