全文获取类型
收费全文 | 5107篇 |
免费 | 91篇 |
国内免费 | 11篇 |
专业分类
化学 | 3024篇 |
晶体学 | 10篇 |
力学 | 59篇 |
综合类 | 1篇 |
数学 | 508篇 |
物理学 | 1607篇 |
出版年
2020年 | 55篇 |
2019年 | 38篇 |
2018年 | 41篇 |
2016年 | 66篇 |
2015年 | 62篇 |
2014年 | 68篇 |
2013年 | 108篇 |
2012年 | 125篇 |
2011年 | 172篇 |
2010年 | 103篇 |
2009年 | 90篇 |
2008年 | 157篇 |
2007年 | 195篇 |
2006年 | 181篇 |
2005年 | 162篇 |
2004年 | 170篇 |
2003年 | 143篇 |
2002年 | 117篇 |
2001年 | 116篇 |
2000年 | 92篇 |
1999年 | 85篇 |
1998年 | 73篇 |
1997年 | 71篇 |
1996年 | 85篇 |
1995年 | 94篇 |
1994年 | 105篇 |
1993年 | 98篇 |
1992年 | 115篇 |
1991年 | 73篇 |
1990年 | 62篇 |
1989年 | 56篇 |
1988年 | 69篇 |
1987年 | 68篇 |
1986年 | 63篇 |
1985年 | 67篇 |
1984年 | 60篇 |
1983年 | 48篇 |
1982年 | 69篇 |
1981年 | 57篇 |
1980年 | 51篇 |
1979年 | 52篇 |
1978年 | 53篇 |
1977年 | 50篇 |
1976年 | 42篇 |
1975年 | 48篇 |
1974年 | 47篇 |
1973年 | 63篇 |
1972年 | 32篇 |
1971年 | 41篇 |
1956年 | 31篇 |
排序方式: 共有5209条查询结果,搜索用时 0 毫秒
1.
Georg von Georgievics 《Monatshefte für Chemie / Chemical Monthly》1885,6(1):754-759
Ohne ZusammenfassungDiese Untersuchung ist vor mehr als Jahresfrist infolge Eintrittes in die chemische Praxis abgebrochen worden. Äussere Verhältnisse machen die Vollendung der begonnenen Versuche auch weiterhin unmöglich und sehe ich mich desshalb veranlasst, meine Beobachtungen zu veröffentlichen. 相似文献
2.
W. von der Linden 《Applied Physics A: Materials Science & Processing》1995,60(2):155-165
The reconstruction of physical quantities from (computer-) experimental data is very often hampered by the presence of noise, insufficient information and above all by the ill-posed nature of the underlying inversion problem. It will be demonstrated that the maximum entropy concepts is particularly suited for this type of data-analysis problems. It is based on Bayesian statistics and provides a consistent probabilistic theory to obtain unbiased results, independent of any model assumptions. This is particularly desirable if there is no additional information to justify these hypotheses. If, on the other hand, additional prior knowledge is available, it can be effectively incorporated into the computation, leading to more stringent confidence intervals. 相似文献
3.
von Eynatten G. Ritter T. Bömmel H. E. Dransfeld K. 《Zeitschrift für Physik B Condensed Matter》1987,65(3):341-345
A new model is presented which explains well the dramatic decrease of the Mössbauer line intensities with raising temperatures for freely dispersed iron microscrystals. In contrast to other theories which consider mainly vibration to be responsible we discuss here the decrease in terms of large amplitude diffusive rotational or translational jumps of the particles. Such diffusive jumps lead — in agreement with the observation — to a strong reduction of the Mössbauer-intensity without broadening the line width in a noticeable way. The typical potential well for a diffusing particle in an equilibrium position is derived quantitatively to be 13 meV. The model might be important also for a new understanding of the dynamics of catalytic clusters either in contact with each other or with larger solid surfaces.Part of this work was supported by the DFG Sonderforschungsbereich 306, Konstanz 相似文献
4.
C. von Borczyskowski F. Cichos J. Martin J. Schuster A. Issac J. Brabandt 《The European physical journal. Special topics》2007,144(1):13-25
Optical spectroscopy in combination with wide field or confocal optical
microscopy enables the investigation of single quantum objects such as
organic molecules, II/VI semiconductor quantum dots and silicon nanocrystals.
They all have fluctuations of luminescence intensities on time scales longer
than μs in common. A comparison reveals that despite the large differences
of the nature of the respective quantum objects, the intensity fluctuations
are related to a slow ionisation process followed
by a trapping of the photoejected charge in the non-conducing environment.
Detailed aspects of the dynamics are controlled by the dielectric properties
of the matrix. 相似文献
5.
6.
F. Seiffert R. Schwengner G. Winter L. Funke W. Lieberz R. Reinhardt K. P. Schmittgen D. Weil R. Wrzal K. O. Zell P. von Brentano 《Zeitschrift für Physik A Hadrons and Nuclei》1991,340(2):141-153
Excited states of73Se have been investigated up to spin, 21/2 using techniques of in-beamγ-ray spectroscopy in connection with the70Ge(α, n) reaction. Mean lifetimes of 12 levels have been determined applying Doppler-shift andγ-RF-methods. Five different bands have been identified that reflect a variety of different excitation modes. The decoupled 9/2+ band is likely to correspond to an oblate deformation while the 5/2+ band is interpreted as a strongly coupled prolate band built on the Nilsson configuration [422] 5/2+. The 3/2? band is a strongly coupled band built on the [301] 3/2} configuration.Nuclear reactions:70Ge(α,n),E=14, 16, 18, 19, 20MeV; measuredE γ,I γ,σ(E γ,θ),γγ-coin, linear polarization, DSA,γ(t).75Se deduced levels,I, π, τ, δ(E2/M1), B(σλ). Enriched targets, Ge detectors. 相似文献
7.
Ulrich Mayerhofer T. von Egidy J. Jolie H. G. Börner G. Colvin S. Judge B. Krusche S. J. Robinson K. Schreckenbach S. Brant V. Paar 《Zeitschrift für Physik A Hadrons and Nuclei》1991,341(1):1-8
Gamma rays of199Au obtained after double neutron capture in197Au were measured at the ILL high flux reactor. A level scheme up to 1770 keV excitation energy is established. The result is compared with IBFM and Boson-Fermion-Symmetry calculations. 相似文献
8.
Periodic Nodal Surfaces (PNS) of Fourier series are derived and classified as fundamental invariants of structured matter. Relationships to periodic minimal surfaces PMS and to periodic zero potential surfaces (POPS) are given. A basic set of cubic PNS is represented in arithmetic form. The special importance of the invariance of the zeros to the type of the potential is stressed. 相似文献
9.
10.