全文获取类型
收费全文 | 3107篇 |
免费 | 291篇 |
国内免费 | 14篇 |
专业分类
化学 | 2159篇 |
晶体学 | 11篇 |
力学 | 60篇 |
数学 | 413篇 |
物理学 | 517篇 |
无线电 | 252篇 |
出版年
2024年 | 3篇 |
2023年 | 62篇 |
2022年 | 77篇 |
2021年 | 134篇 |
2020年 | 176篇 |
2019年 | 198篇 |
2018年 | 88篇 |
2017年 | 79篇 |
2016年 | 219篇 |
2015年 | 155篇 |
2014年 | 176篇 |
2013年 | 216篇 |
2012年 | 290篇 |
2011年 | 283篇 |
2010年 | 161篇 |
2009年 | 135篇 |
2008年 | 204篇 |
2007年 | 161篇 |
2006年 | 153篇 |
2005年 | 102篇 |
2004年 | 62篇 |
2003年 | 33篇 |
2002年 | 35篇 |
2001年 | 28篇 |
2000年 | 20篇 |
1999年 | 19篇 |
1998年 | 14篇 |
1997年 | 10篇 |
1996年 | 10篇 |
1995年 | 14篇 |
1994年 | 9篇 |
1993年 | 5篇 |
1992年 | 11篇 |
1991年 | 7篇 |
1990年 | 6篇 |
1988年 | 3篇 |
1987年 | 6篇 |
1986年 | 5篇 |
1984年 | 2篇 |
1983年 | 3篇 |
1981年 | 6篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1978年 | 6篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1973年 | 3篇 |
1966年 | 2篇 |
1932年 | 2篇 |
1883年 | 1篇 |
排序方式: 共有3412条查询结果,搜索用时 0 毫秒
41.
Theo Steininger Jait Dixit Philipp Frank Maksim Greiner Sebastian Hutschenreuter Jakob Knollmüller Reimar Leike Natalia Porqueres Daniel Pumpe Martin Reinecke Matev raml Csongor Varady Torsten Enßlin 《Annalen der Physik》2019,531(3)
NIFTy , “Numerical Information Field Theory,” is a software framework designed to ease the development and implementation of field inference algorithms. Field equations are formulated independently of the underlying spatial geometry allowing the user to focus on the algorithmic design. Under the hood, NIFTy ensures that the discretization of the implemented equations is consistent. This enables the user to prototype an algorithm rapidly in 1D and then apply it to high‐dimensional real‐world problems. This paper introduces NIFTy 3, a major upgrade to the original NIFTy framework. NIFTy 3 allows the user to run inference algorithms on massively parallel high performance computing clusters without changing the implementation of the field equations. It supports n‐dimensional Cartesian spaces, spherical spaces, power spaces, and product spaces as well as transforms to their harmonic counterparts. Furthermore, NIFTy 3 is able to handle non‐scalar fields, such as vector or tensor fields. The functionality and performance of the software package is demonstrated with example code, which implements a mock inference inspired by a real‐world algorithm from the realm of information field theory. NIFTy 3 is open‐source software available under the GNU General Public License v3 (GPL‐3) at https://gitlab.mpcdf.mpg.de/ift/NIFTy/tree/NIFTy_3 . 相似文献
42.
Sebastian Peil Alois Fürstner 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(51):18647-18652
Enynes with a tethered carbonyl substituent are converted into substituted furan derivatives upon hydrogenation using [Cp*RuCl]4 as the catalyst. Paradoxically, this transformation can occur along two distinct pathways, each of which proceeds via discrete pianostool ruthenium carbenes. In the first case, hydrogenation and carbene formation are synchronized (“gem‐hydrogenation”), whereas the second pathway comprises carbene formation by carbophilic activation of the triple bond, followed by hydrogenative catalyst recycling. Representative carbene intermediates of either route were characterized by X‐ray crystallography; the structural data prove that the attack of the carbonyl group on the electrophilic carbene center follows a Bürgi–Dunitz trajectory. 相似文献
43.
44.
45.
46.
47.
48.
Sebastian Aland Stephan Schwarz Jochen Fröhlich Axel Voigt 《The European physical journal. Special topics》2013,220(1):185-194
In simulations of liquid metals, various model approximations, each of which justified by experimental results lead to a simplified two-phase flow problem. This paper discusses numerical justifications for these approaches and provides quantitative results for a single rising bubble as a benchmark. Representing a bubble as a rigid object is shown to be valid for low Eötvös numbers in contaminated systems. Qualitative differences can be observed for larger Eötvös numbers. Further simulations are undertaken with different ratios of inner and outer viscosity. The benchmark problem considered may also be interesting for more general applications. 相似文献
49.
50.
Bozena Pietrzyk Sebastian Miszczak Hieronim Szymanowski Anna Sobczyk-Guzenda Zbigniew Gawronski 《Journal of Sol-Gel Science and Technology》2013,68(3):455-463
The sol–gel process is widely used for the production of powders, coatings and bulk materials. However, being a wet-chemical technique, it has certain limitations related to properties of aqueous colloidal solution, especially when applied as a coating. The most frequently used methods, such as dip- and spin-coating, are difficult to apply onto more complex substrates. In these cases, the aerosol–gel deposition method can be regarded as the solution of this problem. In the present article, a novel plasma enhanced aerosol–gel method of coatings production is presented. A novelty of this method is based on an integration of the aerosol–gel deposition of thin films and their low temperature plasma treatment. Owing to the above, all stages of the coatings production process—substrate preparation, film deposition, and its plasma treatment, can be carried out in a single reactor. The design and operational scheme of such device is presented in this work. Using this device, thin coatings were first deposited on substrates and then plasma treated. The effect of deposition and plasma discharge conditions on morphology and chemical structure of the films has been studied. It was found that plasma treatment had a substantial influence on all the examined properties of the aerosol–gel deposited coatings. 相似文献