全文获取类型
收费全文 | 1022篇 |
免费 | 51篇 |
国内免费 | 5篇 |
专业分类
化学 | 838篇 |
晶体学 | 7篇 |
力学 | 25篇 |
数学 | 46篇 |
物理学 | 162篇 |
出版年
2023年 | 1篇 |
2022年 | 10篇 |
2021年 | 22篇 |
2020年 | 18篇 |
2019年 | 19篇 |
2018年 | 13篇 |
2017年 | 14篇 |
2016年 | 32篇 |
2015年 | 27篇 |
2014年 | 27篇 |
2013年 | 73篇 |
2012年 | 76篇 |
2011年 | 96篇 |
2010年 | 57篇 |
2009年 | 55篇 |
2008年 | 91篇 |
2007年 | 75篇 |
2006年 | 81篇 |
2005年 | 62篇 |
2004年 | 40篇 |
2003年 | 35篇 |
2002年 | 30篇 |
2001年 | 6篇 |
2000年 | 17篇 |
1999年 | 5篇 |
1998年 | 9篇 |
1997年 | 10篇 |
1996年 | 10篇 |
1995年 | 10篇 |
1994年 | 4篇 |
1993年 | 5篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 5篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1980年 | 1篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 5篇 |
1976年 | 4篇 |
1975年 | 2篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1970年 | 2篇 |
1968年 | 1篇 |
1960年 | 1篇 |
排序方式: 共有1078条查询结果,搜索用时 46 毫秒
891.
Deok Kyu Kim Kyeong Min Kim Choon Bae Park 《Applied Physics A: Materials Science & Processing》2010,98(4):913-917
A p-type ZnO thin film was prepared using arsenic diffusion via the ampoule-tube method. This was followed by fabrication
of a ZnO p–n homojunction using n-type ZnO and characterization of the device properties. The ZnO thin film exhibited p-type
characteristics, with a resistivity of 2.19×10−3 Ω cm, a carrier concentration of 1.73×1020/cm3, and a mobility of 26.7 cm2/V s. Secondary ion mass spectrometer analysis confirmed that in- and out-diffusion occurred simultaneously from the external
As source and the GaAs substrate. The device exhibited the rectification characteristics of a typical p–n junction; the forward
voltage at 20 mA was approximately 5.5 V. The reverse-bias leakage current was very low—0.1 mA for −10 V; the breakdown voltage
was −11 V. The ampoule-tube method for fabricating p-type ZnO thin films may be useful in producing ultraviolet ZnO LEDs and
other ZnO-based devices. 相似文献
892.
Md Alauddin Jae Kyu Song Seung Min Park 《Applied Physics A: Materials Science & Processing》2010,101(4):707-711
Aluminum-doped zinc oxide (AZO) thin films have been deposited on amorphous fused silica substrates by pulsed laser ablation
of a Zn:Al metallic targets. We varied the film growth condition such as the substrate temperature and Al concentrations.
The films were deposited at substrate temperatures ranging from 20 to 600°C with oxygen partial pressure of 1 torr. The characteristics
of the deposited films were examined by analyzing their photoluminescence (PL), X-ray diffraction (XRD), and UV–visible spectra.
It is observed that the optical bandgap energy of the deposited films increased with the increase of Al concentration and
substrate temperature. Besides, the PL peak energy shifted to blue and the Stokes shift became larger as the Al content increased. 相似文献
893.
A patterned metal thin film was synthesized based on a new approach that allows the formation of thin films with complex shape, hierarchical organization, and controlled size under ambient conditions in an aqueous environment. By using a general coating system, a CaCO3 thin film was transformed into a patterned metal thin film with functional properties, such as adhesion and hydrophobicity. Atomic force microscopy (AFM) and surface-profiling experiments were carried out to measure the adhesion between the probe tip and the substrate and to determine the film thickness. Separation of the patterned ceramic thin film occurred very easily by means of sputtering and chemical treatment with an acidic solution. 相似文献
894.
895.
896.
897.
898.
Effects of the disaccharide concentration and the extrusion speed on the size of unilamella vesicles
Dong-Myeong Shin Jeong-Ah Seo Jin-Gun Kim Si-In Kim Kyuyong Lee Haeng Sub Wi Hyun-Joung Kwon Hyuk Kyu Pak Hyung Kook Kim Yoon-Hwae Hwang 《Current Applied Physics》2011,11(6):1401-1404
We investigated the effects of the concentration of disaccharides (trehalose, maltose, and sucrose) and the extrusion speed on the mean size of the unilamella vesicles (ULVs) by using the photon correlation spectroscopy (PCS). We found that the mean diameters of ULVs prepared in the solution with the same disaccharide concentration and the same extrusion speed were quite different. In the case of trehalose, the mean diameter of ULVs decreased as the disaccharide concentration decreased and the extrusion speed increased. Based on those findings, we could fabricate the uniform sized ULVs in different disaccharide solutions with the same concentration by controlling the extrusion speed. 相似文献
899.
Unexpected Carbon Dioxide Inclusion in Water‐Saturated Pores of Metal–Organic Frameworks with Potential for Highly Selective Capture of CO2
下载免费PDF全文
![点击此处可从《Chemistry (Weinheim an der Bergstrasse, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Daeok Kim Hyung‐Kyu Lim Hyeyoon Ro Prof. Hyungjun Kim Prof. Huen Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):1125-1129
Unusual CO2 storage in water‐saturated MOFs was investigated by combining experiment and simulation. It was found that the micropores of HKUST‐1 saturated with water provide an environment that is thermodynamically and kinetically favorable for CO2 capture, but not for N2 and H2 capture. We expect that this phenomenon have potential to be used for successful separation of CO2 from versatile flue streams and pre‐combustion gas. 相似文献
900.