全文获取类型
收费全文 | 264篇 |
免费 | 3篇 |
国内免费 | 2篇 |
专业分类
化学 | 154篇 |
力学 | 28篇 |
数学 | 47篇 |
物理学 | 40篇 |
出版年
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 6篇 |
2020年 | 4篇 |
2019年 | 1篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 12篇 |
2015年 | 7篇 |
2014年 | 4篇 |
2013年 | 15篇 |
2012年 | 23篇 |
2011年 | 16篇 |
2010年 | 10篇 |
2009年 | 8篇 |
2008年 | 7篇 |
2007年 | 10篇 |
2006年 | 5篇 |
2005年 | 9篇 |
2004年 | 7篇 |
2003年 | 10篇 |
2002年 | 9篇 |
2001年 | 9篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 7篇 |
1995年 | 8篇 |
1994年 | 7篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 4篇 |
1988年 | 2篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 2篇 |
1984年 | 6篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1971年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有269条查询结果,搜索用时 218 毫秒
21.
22.
Masciocchi N Ardizzoia GA Brenna S Castelli F Galli S Maspero A Sironi A 《Chemical communications (Cambridge, England)》2003,(16):2018-2019
Two new 3D homoleptic binary imidazolates, Cd(im)2 and Hg(im)2 (Him = imidazole), as well as [Hg(im)]NO3, containing 1D polycations of [Hg(im)]n(n+) formulation, have been prepared and characterized by ab-initio XRPD methods. 相似文献
23.
24.
We discuss local solvability of operators of the form
where theV
j
are left-invariant vector fields on the Heisenberg group such that [V
j
,V
j+n
]=U for 1≤j≤n andA=(a
jk
)=A
1+iA
2 is a complex symmetric matrix satisfying the “cone condition” |A
2|≤CA
1.
The authors acknowledge the support for this work by the European Commission through the European HCM-program “Fourier Analysis”
and the TMR network “Harmonic Analysis”. 相似文献
25.
Given a real polynomial in one variable such that , we consider the maximal operator in ,
We prove that is bounded on for 1$"> with bounds that only depend on the degree of .
0\,,\,i,j\in \mathbb{Z}}\frac{1... ...t f\big (x_{1}-2^{i}p(t),x_{2}-2^{j}p(t)\big )\big \vert\,dt . \end{displaymath}">
We prove that is bounded on for 1$"> with bounds that only depend on the degree of .
26.
Fulvio Ricci Giancarlo Travaglini 《Proceedings of the American Mathematical Society》2001,129(6):1739-1744
Let be a convex curve in the plane and let be the arc-length measure of Let us rotate by an angle and let be the corresponding measure. Let . Then This is optimal for an arbitrary . Depending on the curvature of , this estimate can be improved by introducing mixed-norm estimates of the form where and are conjugate exponents. 相似文献
27.
The paper tackles the problem of pricing, under interest-rate risk, a default-free sinking-fund bond which allows its issuer to recurrently retire part of the issue by (a) a lottery call at par, or (b) an open market repurchase. By directly modelling zero-coupon bonds as diffusions driven by a single-dimensional Brownian motion, a pricing formula is supplied for the sinking-fund bond based on a backward induction procedure which exploits, at each step, the martingale approach to the valuation of contingent-claims. With more than one sinking-fund date, however, the pricing formula is not in closed form, not even for simple parametrizations of the process for zerocoupon bonds, so that a numerical approach is needed. Since the computational complexity increases exponentially with the number of sinking-fund dates, arbitrage-based lower and upper bounds are provided for the sinking-fund bond price. The computation of these bounds is almost effortless when zero-coupon bonds are as described by Cox, Ingersoll and Ross. Numerical comparisons between the price of the sinking-fund bond obtained via Monte Carlo simulation and these lower and upper bounds are illustrated for different choices of parameters. 相似文献
28.
Giovanna Bruni Vittorio Berbenni Franco Sartor Chiara Milanese Alessandro Girella Dionigio Franchi Amedeo Marini 《Journal of Thermal Analysis and Calorimetry》2012,108(1):235-241
In this work, thermoanalytical, diffractometry, and microscopy measurements have been performed in order to characterize the
effect of high energy milling on a drug active in the migraine prophylaxis and smoke cessation. We can assert that the mechanical
treatment induces only a partial amorphisation of the solid phase, in particular it reduces the crystal order by producing
lattice defects which propagate from the surface to the bulk crystal. For this reason, the DSC is able to detect the presence
of ordered solid, while the powder X-ray diffractometry, because of its low penetration depth, does not reach the crystalline
core of the particles. 相似文献
29.
30.