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51.
Dag?Fjeld?Edvardsen Finn?R.?F?rsundEmail author Sverre?A.?C.?Kittelsen 《The Journal of the Operational Research Society》2017,68(4):399-415
Productivity growth of institutions of higher education is of interest for two main reasons: education is an important factor for productivity growth of the economy, and in countries where higher education is funded by the public sector, accountability of resource use is of key interest. Educational services consist of teaching, research and the “third mission” of dissemination of knowledge to the society at large. A bootstrapped Malmquist productivity change index is used to calculate productivity development for Norwegian institutions of higher education over the 10-year period 2004–2013. The confidence intervals from bootstrapping allow part of the uncertainty of point estimates stemming from sample variation to be revealed. The main result is that the majority of institutions have had a positive productivity growth over the total period. However, when comparing with growth in labour input, the impact on productivity varies a lot. 相似文献
52.
R. F. Payne S. M. Schulte M. Douglas J. I. Friese O. T. FarmerIII E. C. Finn 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(3):863-867
Lanthanides are common fission products and the ability to separate and quantify these elements is critical to rapid radiochemistry
applications. Published lanthanide separations using Eichrom Ln Spec resin utilize an HCl gradient. Here it is shown that
the efficacy and resolution of the separation is improved when a nitric acid gradient is used instead. The described method
allows parallel processing of many samples in 1.5 h followed by 60 min counting for quantification of 9 radioisotopes of 7
lanthanide elements. 相似文献
53.
Finn ST Strnad JA Barreto PD Fox ME Torres J Sweeney JD Barreto JC 《Photochemistry and photobiology》2011,87(5):1184-1188
We describe a screening methodology that can be used to quickly determine the effectiveness of newly synthesized photocatalysts. We were particularly interested in measuring the destruction of organic molecules painted onto a photocatalytic surface by spraying, with destruction proceeding in ambient air (as a model for airborne toxin destruction). Our method can utilize photocatalysts that are synthesized as powders (such as doped and undoped titanium oxide) and which are then calcined onto a glass substrate disk at 600°C. Herein, we used UV illumination of Aeroxide P-25 TiO(2), but the method is general and can accommodate any region of the light spectrum. 相似文献
54.
Johnson JA Lu YY Burts AO Lim YH Finn MG Koberstein JT Turro NJ Tirrell DA Grubbs RH 《Journal of the American Chemical Society》2011,133(3):559-566
The combination of highly efficient polymerizations with modular "click" coupling reactions has enabled the synthesis of a wide variety of novel nanoscopic structures. Here we demonstrate the facile synthesis of a new class of clickable, branched nanostructures, polyethylene glycol (PEG)-branch-azide bivalent-brush polymers, facilitated by "graft-through" ring-opening metathesis polymerization of a branched norbornene-PEG-chloride macromonomer followed by halide-azide exchange. The resulting bivalent-brush polymers possess azide groups at the core near a polynorbornene backbone with PEG chains extended into solution; the structure resembles a unimolecular micelle. We demonstrate copper-catalyzed azide-alkyne cycloaddition (CuAAC) "click-to" coupling of a photocleavable doxorubicin (DOX)-alkyne derivative to the azide core. The CuAAC coupling was quantitative across a wide range of nanoscopic sizes (~6-~50 nm); UV photolysis of the resulting DOX-loaded materials yielded free DOX that was therapeutically effective against human cancer cells. 相似文献
55.
Both inter- and intramolecular degradation pathways were identified for the aqueous phase deactivation of oxanorbornadiene (OND) electrophiles, and propargylic OND esters were found to undergo facile intramolecular [2 + 2 + 2] homo-Diels-Alder cycloaddition in polar media. 相似文献
56.
Type-I coil planet centrifuge produces a uniformly circulating centrifugal force field to produce vortex motion of two immiscible solvent phases in a cylindrical cavity of the separation column to perform efficient countercurrent chromatography. The partition efficiency obtained from the original vortex column was substantially improved by threading the cylindrical cavity to increase the area of mass transfer between the two phases. Partition efficiency of the threaded column was evaluated by three different two-phase solvent systems with a broad range of hydrophobicity each with a set of suitable test samples. Overall results of the present studies indicated that the threaded cylindrical column substantially improves the partition efficiency in terms of theoretical plate number, peak resolution, and height equivalent of one theoretical plate. The results also indicated that higher peak resolution is produced by eluting either the upper phase in the head to tail direction or the lower phase in the reversed direction. When there is a choice in the mobile phase, a better separation is achieved by using the less viscous phase as the mobile phase. Since the present system gives extremely low column pressure, it may be a potential alternative to the conventional type-J HSCCC system for a large-scale preparative separation. 相似文献
57.
Robert Finn 《Journal of Mathematical Fluid Mechanics》2011,13(1):103-115
Conditions are determined under which solid bodies will float on a liquid surface in stable equilibrium, under the influence
of gravity and of surface tension. These include configurations in which the density of the body exceeds the density of the
ambient liquid, so that for an infinitely deep liquid in a downward gravity field there is no absolute energy minimum. Of
notable interest are the results (a) that if a smooth body is held rigidly and translated downward into an infinite fluid
bath through a family of fluid equilibrium configurations in a downward gravity field, the transition is necessarily discontinuous,
and (b) a formal proof that there can be a free-floating locally energy minimizing configuration that does not globally minimize,
even if the density of the body exceeds that of the liquid. The present work is limited to the two dimensional case corresponding
to a long cylinder that is floating horizontally. The more physical three-dimensional case can be studied in a similar way,
although details of behavior can change significantly. That work will appear in an independent study written jointly with
T. I. Vogel. 相似文献
58.
59.
60.
Sunto In un importante lavoro [1], M. Emmer ha dimostrato l’esistenza di superfici di equilibrio capillari, definite in domini con
frontiera Lipschitziana, quando la costante di Lipschitz L e l’angolo di contatto γ soddisfano la relazione L<|tg γ|. Questa condizione, che è noto essere necessaria in generale, può essere troppo restrittiva in alcuni casi particolari.
In questo lavoro la condizione di Emmer è sostituita da una ? condizione di sfera interna ?, che conduce ad una larga classe
di domini che non rientrano nel risultato di Emmer. L’esiestenza di una soluzione è dimostrata anche nel caso γ=0, che non
può essere trattato con il metodo di Emmer.
Entrata in Redazione il 26 agosto 1975.
This work was initiated while the former author was at Universit?t Bonn and at Università di Genova, and the latter author at Université de Paris VI as a Fellow of the Deutsche Forschungsgemeinschaft. 相似文献
Entrata in Redazione il 26 agosto 1975.
This work was initiated while the former author was at Universit?t Bonn and at Università di Genova, and the latter author at Université de Paris VI as a Fellow of the Deutsche Forschungsgemeinschaft. 相似文献