全文获取类型
| 收费全文 | 190篇 |
| 免费 | 2篇 |
| 国内免费 | 3篇 |
专业分类
| 化学 | 113篇 |
| 晶体学 | 3篇 |
| 力学 | 15篇 |
| 数学 | 22篇 |
| 物理学 | 42篇 |
出版年
| 2024年 | 4篇 |
| 2023年 | 1篇 |
| 2022年 | 4篇 |
| 2021年 | 6篇 |
| 2020年 | 7篇 |
| 2019年 | 11篇 |
| 2018年 | 16篇 |
| 2017年 | 7篇 |
| 2016年 | 21篇 |
| 2015年 | 8篇 |
| 2014年 | 11篇 |
| 2013年 | 10篇 |
| 2012年 | 9篇 |
| 2011年 | 17篇 |
| 2010年 | 13篇 |
| 2009年 | 8篇 |
| 2008年 | 13篇 |
| 2007年 | 6篇 |
| 2006年 | 6篇 |
| 2005年 | 7篇 |
| 2003年 | 1篇 |
| 2002年 | 4篇 |
| 1999年 | 3篇 |
| 1982年 | 1篇 |
| 1978年 | 1篇 |
排序方式： 共有195条查询结果，搜索用时 0 毫秒
21.
22.
Farzad Zamani Rasool Babaahmadi Brian F. Yates Michael G. Gardiner Alireza Ariafard Stephen G. Pyne Christopher J. T. Hyland 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(7):2136-2141
A synthesis of unconjugated (E)‐enediynes from allenyl amino alcohols is reported and their gold‐catalyzed cascade cycloaromatization to a broad range of enantioenriched substituted isoindolinones has been developed. Experimental and computational studies support the reaction proceeding via a dual‐gold σ,π‐activation mode, involving a key gold‐vinylidene‐ and allenyl‐gold‐containing intermediate. 相似文献
23.
A multiscale framework is presented for the development of continuum models for 2D materials. The framework consists of four steps. First the 2D material is studied by performing a set of Density Functional Theory (DFT) simulations. A continuum model consistent with the material properties is then developed. The continuum model is calibrated based on the generated DFT data. Finally, the model is validated from new DFT data. The generation of DFT results and the calibration of the continuum model are discussed in this paper and a numerical example of a pressurized square phosphorus sheet is presented. The framework has previously been applied to graphene and single layer blue phosphorus. 相似文献
24.
Reza Farzad Stefan Puttinger Stefan Pirker Simon Schneiderbauer 《Journal of Dispersion Science and Technology》2018,39(2):250-258
In this paper, we investigate oil-in-water emulsions in a Taylor-Couette flow. A high-speed camera was employed to record the formation of those emulsions, and image processing was used to obtain the diameter of the droplets. No surfactants were added in order to study the pure effect of the fluid dynamical forces on the droplets. The results for three different oil-in-water emulsions show that the Sauter mean diameter considerably depends on the local shear rate and the material properties and that the droplet size distribution follows a log-normal distribution. We, therefore, propose to express the Sauter mean diameter normalized by Prandtl mixing length in terms of a correlation, which is based on the Kolmogorov turbulence theory. This correlation subsequently depends on the local shear rate and the material properties such as viscosity, density, and interfacial tension. The predictions of the correlation show fairly good agreement with the experimental measurement the Sauter mean diameter. Finally, comparing the predictions of the correlation to the data presented by Eskin et al. [Chem. Eng. Sci. 161 36–47; 2017] shows excellent agreement in the case, where the droplets are larger than the Kolmogorov length scale. 相似文献
25.
Farzad Radmehr Michael Drake 《International Journal of Mathematical Education in Science & Technology》2017,48(8):1206-1224
In this paper, the knowledge dimension for Revised Bloom's taxonomy (RBT) is unpacked for integral calculus. As part of this work, the 11 subtypes of the knowledge dimension are introduced, and through document analysis of chapter 4 of the RBT handbook, these subtypes are defined. Then, by consulting materials frequently used for teaching integral calculus, each subtype is exemplified. The developed dimension may enable or enhance opportunities for dialogue between lecturers, teachers, and researchers about how to develop and align educational objectives, teaching activities, and assessments in integral calculus, or how metacognition and metacognitive knowledge could be used to support teaching and learning. 相似文献
26.
Farzad Radmehr Michael Drake 《International Journal of Mathematical Education in Science & Technology》2017,48(7):1043-1071
Several studies have explored students’ understanding of the relationships between definite integrals and areas under curve(s). So far, however, there has been less attention to students’ understanding of the Fundamental Theorem of Calculus (FTC). In addition, students’ metacognitive experiences and skills whilst solving FTC questions have not previously been explored. This paper explored students’ mathematical performance, metacognitive experiences and metacognitive skills in relation to FTC questions by interviewing nine university and eight Year 13 students. The findings show that several students had difficulty solving questions related to the FTC and that students’ metacognitive experiences and skills could be further developed. 相似文献
27.
This article deals with the wave propagation analysis of single/double layered functionally graded (FG) size-dependent nanobeams in elastic medium and subjected to a longitudinal magnetic field employing nonlocal elasticity theory. Material properties of nanobeam change gradually according to the sigmoid function. Applying an analytical solution, the acoustical and optical dispersion relations are explored for various wave number, nonlocality parameter, material composition, elastic foundation constants, and magnetic field intensity. It is found that frequency and phase velocity of waves propagating in S-FGM nanobeam are significantly affected by these parameters. Also, presence of cut-off and escape frequencies in wave propagation analysis of embedded S-FGM nanobeams is investigated. 相似文献
28.
In this paper, we report on the surface roughness evolution of highly ordered anodic aluminum oxide (AAO) films based on an atomic force microscopy (AFM) study. Root mean square of the surface roughness was measured on AFM images taken from highly ordered AAO films produced by two-step anodization under different conditions including electrolyte type, anodization voltage, and anodization time. Surface roughness of highly ordered AAO films increases step by step through the two-step anodizing process including electropolishing, first-step anodization, dissolution, and second-step anodization. However, increase of the surface roughness is proportional to the anodization voltage and time. The surface roughness of AAO films changes as a function of length scale until it finally approaches a maximum termed the saturation roughness. The variation of roughness of the growth of AAO could be scaled with an anomalous dynamic behavior as it saturates over a critical length scale while the saturation roughness is dependent on the anodizing time and voltage. 相似文献
29.
30.