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101.
《Comptes Rendus Physique》2013,14(6):447-450
One of the major emerging fields of research of the beginning of this century concerns living fluids. By “living fluids”, we mean two major categories of complex fluids: (i) fluids which are essential to life, like blood, and (ii) active fluids made of particles that are able to propel themselves in the suspending fluid by converting a form of their energy into mechanical motion. Studies on active fluids have known a considerable interest since the last decade. Blood might be viewed as an old topic, but the progresses in experimental techniques, analytical concepts and numerics, have contributed nowadays to a dramatic renewal of the interest in this field, with a great potential towards understanding physical and mechanical factors in cardiovascular diseases. These fields have considerably strengthened interdisciplinary research. The series of reviews of this dossier focus on the tremendous recent progress achieved in research on living fluids both from the experimental and theoretical points of views. These reviews present also the major open issues, making of this dossier a unique guide for future research in these fields. This project grew up thanks to the international summer school that we organized on the topic “living fluids” at the IES (Institut dʼétudes scientifiques) of Cargèse (Corsica) in 2012. 相似文献
102.
Catalyzed by ytterbium(III) triflate hydrate [Yb(OTf)3.xH20], the Michael addition and cyclocondensation of α,β-unsaturated ketones with active methylene compounds to afford the 1,4-adducts and benzo[b]pyran derivatives, respectively were studied. 相似文献
103.
D. Michael Heinekey 《Journal of organometallic chemistry》2009,694(17):2671-1091
Recent developments in active site structure determination of the three types of hydrogenase enzymes are described. Aspects of recent studies using model complexes relevant to the structure and function of the enzymes are reviewed. 相似文献
104.
M. K. Kullab B. A. Al-Bataina A. M. Ismail K. M. Abumurad 《Radiation measurements》2001,34(1-6):361-364
Previously calibrated passive detectors (CR-39) and an active radon device (Radon Monitor RM3) were used to study seasonal variation of radon-222 concentration levels inside and outside specific locations in Jordan. The study sites were located in an area that used to be an old phosphate mine. We found that the maximum value of radon concentration in air inside the dwellings, as measured by the passive dosimeters, was 1532.9 Bq/m3 during the winter season, and the minimum one was 46.3 Bq/m3 during fall season. While the highest and lowest readings of the active monitor were 892 and 4 Bq/m3 during fall and summer seasons, respectively. The radon concentration in soil ranges from 0.2 kBq/m3 in spring to 37.8 kBq/m3 in fall. 相似文献
105.
Renliang Xu 《中国颗粒学报》2008,6(2)
Characterization of various nanoparticles is on the center stage in nanotechnology development. The subjects for nanoparticles characterization are focused on particle size and particle surface charge determinations. This article summarizes the latest development in particle size analysis using dynamic light scattering and surface charge determination using electrophoretic light scattering for nano- or even sub-nanoparticles in concentrated suspensions. 相似文献
106.
107.
A new type of acoustic liner developed for broadband noise reduction in flow ducts is considered in this paper. It combines passive absorbent properties of a porous layer and active control at its rear face. The complete design procedure of this hybrid passive/active liner is developed here. The passive part is first considered with the determination of a suitable porous material and the cut-off frequency separating the active low frequency regime from the passive high frequency one. The control system is then presented: a digital adaptive feedback control is performed independently cell by cell, allowing an easy subsequent increase of the liner surface. The entire optimization process has been successfully applied to a laboratory flow duct: both predictions and measurements show the interest of the hybrid liner to reduce the noise radiation. 相似文献
108.
A repetitive potential cycling procedure was used to produce a specific multilayer hydrous oxide film on copper in base at
60 °C. Such a deposit undergoes reduction in a quasi-reversible manner at ca. −0.1 V (RHE), i.e. at a potential that is unrelated
to Pourbaix data for copper but, as demonstrated previously, is of major significance with regard to the electrocatalytic
behaviour of this electrode system. In accordance with the incipient hydrous oxide/adatom mediator model of electrocatalysis,
an active surface state of the metal (Cu*) is assumed to be involved both in electrocatalysis and as a primary product in
the hydrous oxide reduction reaction. While the latter process occurs very rapidly at −0.1 V, it is not usually reversible
as it is accompanied by subsequent rapid loss of the active state of the metal. The same general approach was used previously
to explain the hydrous oxide and electrocatalytic behaviour of a range of noble metals.
Received: 28 August 1999 / Accepted: 11 November 1999 相似文献
109.
E. Polak R. S. Womersley H. X. Yin 《Journal of Optimization Theory and Applications》2008,138(2):311-328
We present a new active-set strategy which can be used in conjunction with exponential (entropic) smoothing for solving large-scale
minimax problems arising from the discretization of semi-infinite minimax problems. The main effect of the active-set strategy
is to dramatically reduce the number of gradient calculations needed in the optimization. Discretization of multidimensional
domains gives rise to minimax problems with thousands of component functions. We present an application to minimizing the
sum of squares of the Lagrange polynomials to find good points for polynomial interpolation on the unit sphere in ℝ3. Our numerical results show that the active-set strategy results in a modified Armijo gradient or Gauss-Newton like methods
requiring less than a quarter of the gradients, as compared to the use of these methods without our active-set strategy. Finally,
we show how this strategy can be incorporated in an algorithm for solving semi-infinite minimax problems. 相似文献
110.
Catalyzed by ytterbium(Ⅲ) triflate hydrate [Yb(OTf)3.xH2O], the Michael addition and cycloeondensation of α,β-unsaturated ketones with active methylene compounds to afford the 1,4-adducts and benzo[b]pyran derivatives, respectively were studied. 相似文献