全文获取类型
收费全文 | 178篇 |
免费 | 7篇 |
国内免费 | 2篇 |
专业分类
化学 | 79篇 |
力学 | 12篇 |
数学 | 46篇 |
物理学 | 50篇 |
出版年
2023年 | 3篇 |
2022年 | 6篇 |
2021年 | 3篇 |
2020年 | 8篇 |
2019年 | 8篇 |
2018年 | 4篇 |
2017年 | 10篇 |
2016年 | 14篇 |
2015年 | 8篇 |
2014年 | 12篇 |
2013年 | 17篇 |
2012年 | 13篇 |
2011年 | 14篇 |
2010年 | 19篇 |
2009年 | 11篇 |
2008年 | 9篇 |
2007年 | 9篇 |
2006年 | 5篇 |
2005年 | 5篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 1篇 |
2001年 | 1篇 |
1999年 | 1篇 |
1991年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
排序方式: 共有187条查询结果,搜索用时 31 毫秒
41.
42.
Fethi Mahmoudi 《Advances in Mathematics》2007,209(2):460-525
We consider the equation −ε2Δu+u=up in Ω⊆RN, where Ω is open, smooth and bounded, and we prove concentration of solutions along k-dimensional minimal submanifolds of ∂Ω, for N?3 and for k∈{1,…,N−2}. We impose Neumann boundary conditions, assuming 1<p<(N−k+2)/(N−k−2) and ε→0+. This result settles in full generality a phenomenon previously considered only in the particular case N=3 and k=1. 相似文献
43.
W. F. Mahmoudi N. Ben Nessib S. Sahal-Bréchot 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,47(1):7-10
Owing to the increasing sensitivity of detectors,
accurate line profiles are needed for accurate stellar
atmospheres modelling and for laboratory and technological plasmas
as well. So, Stark broadening parameters of isolated lines of
complex atoms and ions within the impact and quasistatic
approximation are needed, even if the atomic abundance of the considered element is low.
Angular factors of the diagonal line strength entering the
quadrupole term appearing in the semi-classical expression of the
width of line broadened by electron or ion perturbers, are needed.
The aim of this paper is to extend the previous calculations of
this diagonal multiplet factor which were obtained for
configurations of the type ln and l1
nl2
m to
more complex configurations in LS coupling.
To study the Stark broadening of isolated lines in the impact and
quasistatic approximation, we use the semi-classical-perturbation
treatment, including both dipole and quadrupole contribution in
the expansion of the electrostatic interaction between the optical
electron and the perturber. We also use the Fano-Racah algebra.
Angular factors of the diagonal line strength entering the
quadrupole term appearing in the semi-classical expression of the
width of line broadened by electron or ion perturbers, are
calculated. New diagonal multiplet factor formulae for more
complicated configurations such as
(n1l1
n(LnSn)n2l2
m(LmSm)n3l3
p(LpSp))
are provided.
These formulae can enter the computer Stark semi-classical
perturbation codes. 相似文献
44.
Majid Montazer Mahbubeh Dastjerdi Maryam Azdaloo Mahnaz Mahmoudi Rad 《Cellulose (London, England)》2015,22(6):4049-4064
45.
46.
47.
Transmission and reflection of an electromagnetic pulse through a dielectric slab doped with the quantum dot molecules are investigated. It is shown that the transmission and reflection coefficients depend on the inter-dot tunneling effect and can be simply controlled by applying a gate voltage without any changing in the refractive index or thickness of the slab. Such simple controlling prepares an active beam splitter which can be used in all optical switching, optical limiting, and other optical systems. 相似文献
48.
Amir Behzadnia Majid Montazer Abousaeid Rashidi Mahnaz Mahmoudi Rad 《Photochemistry and photobiology》2014,90(6):1224-1233
Nano nitrogen‐doped titanium dioxide was rapidly prepared by hydrolysis of titanium isopropoxide at 75–80°C using in situ sonochemical synthesis by introducing ammonia. Various concentrations of titanium isopropoxide were examined to deposit nano nitrogen‐doped titanium dioxide through impregnation of the wool fabric in ultrasound bath followed by curing. The antibacterial/antifungal activities of wool samples were assessed against two common pathogenic bacteria including Escherichia coli and Staphylococcus aureus and the diploid fungus Candida albicans. The sonotreated wool fabrics indicated no adverse effects on human dermal fibroblasts. The presence of nanoparticles on the sonotreated wool fabrics were confirmed by FE‐SEM images and EDS patterns and X‐ray mapping and the crystalline size of nanoparticles were estimated through XRD results. The role of both pH and precursor concentration on the various properties of the fabric was investigated and the optimized conditions introduced using response surface methodology. 相似文献
49.
M. Sahrai S. Aas M. Aas M. Mahmoudi 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,83(3):337-342
The Hartman effect in one-dimensional photonic crystals contained a defect layer doped
with two-level, and three-level atoms is discussed. It is shown that the transmitted phase
time in one-dimensional photonic crystals contained a defect layer reaches to a positive
constant as the periodic number N increases. However, for a defect layer
doped by two-level atoms, the transmitted phase time reaches to negative constant by
increasing periodic number N. In addition, for defect layer doped by
three-level atoms, the transmitted phase time can be controlled from positive to negative
just by the Rabi-frequency of coupling field. 相似文献
50.
Projection algebras are M-sets for the monoid M = (ℕ∞, min) which are used by computer scientists for algebraic specification of process algebras. In contrast to the case of
modules it is well known that the Baer Criterion does not generally hold for injectivity of M-sets for an arbitrary monoid
M. Here, introducing a closure operator, we prove that the Baer Criterion does hold for injectivity of projection algebras. 相似文献