全文获取类型
收费全文 | 1135篇 |
免费 | 56篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 17篇 |
化学工业 | 359篇 |
金属工艺 | 16篇 |
机械仪表 | 15篇 |
建筑科学 | 58篇 |
矿业工程 | 3篇 |
能源动力 | 36篇 |
轻工业 | 102篇 |
水利工程 | 2篇 |
石油天然气 | 7篇 |
无线电 | 63篇 |
一般工业技术 | 177篇 |
冶金工业 | 166篇 |
原子能技术 | 9篇 |
自动化技术 | 163篇 |
出版年
2023年 | 16篇 |
2022年 | 19篇 |
2021年 | 57篇 |
2020年 | 23篇 |
2019年 | 24篇 |
2018年 | 28篇 |
2017年 | 31篇 |
2016年 | 31篇 |
2015年 | 30篇 |
2014年 | 35篇 |
2013年 | 88篇 |
2012年 | 42篇 |
2011年 | 63篇 |
2010年 | 47篇 |
2009年 | 39篇 |
2008年 | 57篇 |
2007年 | 47篇 |
2006年 | 38篇 |
2005年 | 28篇 |
2004年 | 28篇 |
2003年 | 22篇 |
2002年 | 25篇 |
2001年 | 13篇 |
2000年 | 15篇 |
1999年 | 19篇 |
1998年 | 39篇 |
1997年 | 17篇 |
1996年 | 15篇 |
1995年 | 11篇 |
1994年 | 12篇 |
1993年 | 10篇 |
1992年 | 9篇 |
1991年 | 10篇 |
1990年 | 8篇 |
1989年 | 11篇 |
1987年 | 7篇 |
1986年 | 6篇 |
1985年 | 12篇 |
1984年 | 7篇 |
1983年 | 12篇 |
1982年 | 6篇 |
1980年 | 6篇 |
1979年 | 8篇 |
1978年 | 7篇 |
1976年 | 12篇 |
1975年 | 7篇 |
1973年 | 8篇 |
1972年 | 9篇 |
1970年 | 6篇 |
1966年 | 6篇 |
排序方式: 共有1193条查询结果,搜索用时 9 毫秒
1.
2.
J. H. Edgar C. A. Carosella C. R. Eddy Jr D. T. Smith 《Journal of Materials Science: Materials in Electronics》1996,7(4):247-253
The effects of nitrogen-beam voltage on the structure, stress, energy band gap and hardness of AIN thin films deposited on Si (111), Si (100) and sapphire (0001) by ion beam assisted deposition (IBAD) are reported. As the nitrogen-beam voltage was increased from 50 to 200 V, the stress and disorder in the AIN films increased as determined by X-ray diffraction, FTIR and Raman spectroscopy. The preferred orientation of the film's c-axis changed from completely normal to the film at 100 V, to a mixture of normal and in the plane of the film at 200 V. For AIN films deposited under the same conditions, the films were more highly oriented on sapphire (0001) than in Si (111). The hardness of the films increased from 18.2 to 23.7 GPa with the nitrogen-beam voltage, and possible reasons for this change in hardness are considered. 相似文献
3.
Edgar B. Gutoff 《Drying Technology》1996,14(7):1673-1693
A complete model for the drying of coated webs. as implemented in the spreadsheet DRYWEB for Lotus and for Excel, is described. The model predicts the temperatures and solvent levels throughout the length of the dryer. The initial transient as the coated web approaches the equilibrium temperature in the consiant rate period is calculated. The coating is divided into slices for a finite difference calculation of solvent diffusion to the surface, using a simple free volume model of diffusion. The semi-empirical constants needed can be found from one or two trial runs. The possible use of infra-red heating in addition to convection heating is included in both the constant and falling rates. The calculation of infra-red energy is discussed. The model assumes that the temperature is uniform from the top of the coating to the bottom of the base, and that assumption is justified. 相似文献
4.
5.
6.
Kivlighan Dennis M.; Marsh-Angelone Maureen; Angelone Edgar O. 《Canadian Metallurgical Quarterly》1994,41(1):99
Explored projection in group counseling by examining the relationship between the group members' interpersonal problems and their perception of the group leader. Before participation, 118 personal-growth group members filled out the Inventory of Interpersonal Problems by L. M. Horowitz et al (see record 1989-10599-001) and after each session they filled out the Trainer Behavior Scale (L. Bolman, 1971). A latent variable analysis revealed that during the 1st 10 group sessions, overly dominant group members perceived the group leaders as more dominant and overly cold group members perceived the group leaders as less affiliative. There was less relationship between group members' interpersonal problems and ratings for group leaders over time. Implications of these results are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
8.
The combustion behaviour of four different lignite samples pyrolysed at 800 and 1000 °C has been studied. The reaction order and the activation energy of the char combustion reaction can be easily determined from the time to reach 50% conversion. Under 550 °C the reaction order of lignite samples are 0.7 and the activation energies are 27.4–27.9 kcal gmole?1. Above 550 °C the measurement of the intrinsic reaction rate is limited by the film diffusion resistance. The pyrolysis temperature affects the reactivity significantly. The reactivity of char pyrolysed at 800 °C is 3.5 times that of char pyrolysed at 1000 °C. 相似文献
9.
Tellez Eric S. Ruiz Guillermo Chavez Edgar Graff Mario 《Pattern Analysis & Applications》2021,24(2):763-777
Pattern Analysis and Applications - Nearest neighbor search is a powerful abstraction for data access; however, data indexing is troublesome even for approximate indexes. For intrinsically... 相似文献
10.
Pattern Analysis and Applications - This work presents a gesture-based approach to estimate task understanding and performance during remote ultrasound tasks. Our approach is comprised of... 相似文献