全文获取类型
收费全文 | 83955篇 |
免费 | 4814篇 |
国内免费 | 2966篇 |
专业分类
电工技术 | 4174篇 |
技术理论 | 26篇 |
综合类 | 6623篇 |
化学工业 | 11431篇 |
金属工艺 | 3797篇 |
机械仪表 | 4776篇 |
建筑科学 | 10937篇 |
矿业工程 | 5047篇 |
能源动力 | 2154篇 |
轻工业 | 7687篇 |
水利工程 | 2148篇 |
石油天然气 | 3892篇 |
武器工业 | 2157篇 |
无线电 | 8560篇 |
一般工业技术 | 4318篇 |
冶金工业 | 4089篇 |
原子能技术 | 418篇 |
自动化技术 | 9501篇 |
出版年
2024年 | 159篇 |
2023年 | 739篇 |
2022年 | 1688篇 |
2021年 | 2233篇 |
2020年 | 2217篇 |
2019年 | 1294篇 |
2018年 | 1172篇 |
2017年 | 1849篇 |
2016年 | 2214篇 |
2015年 | 2476篇 |
2014年 | 6496篇 |
2013年 | 4511篇 |
2012年 | 6231篇 |
2011年 | 6618篇 |
2010年 | 5101篇 |
2009年 | 5232篇 |
2008年 | 4775篇 |
2007年 | 5813篇 |
2006年 | 5289篇 |
2005年 | 4593篇 |
2004年 | 3970篇 |
2003年 | 3614篇 |
2002年 | 2968篇 |
2001年 | 2509篇 |
2000年 | 1920篇 |
1999年 | 1485篇 |
1998年 | 1019篇 |
1997年 | 780篇 |
1996年 | 619篇 |
1995年 | 520篇 |
1994年 | 397篇 |
1993年 | 276篇 |
1992年 | 234篇 |
1991年 | 153篇 |
1990年 | 131篇 |
1989年 | 109篇 |
1988年 | 82篇 |
1987年 | 49篇 |
1986年 | 54篇 |
1985年 | 32篇 |
1984年 | 29篇 |
1983年 | 13篇 |
1982年 | 13篇 |
1981年 | 12篇 |
1980年 | 13篇 |
1979年 | 5篇 |
1978年 | 5篇 |
1975年 | 3篇 |
1959年 | 2篇 |
1951年 | 9篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
21.
社会经济快速发展,科学技术不断进步,针对我国现代工业化工行业发展,所产生的新型化工技术应用,促进我国化工生产效率的提升。工业的发展不可避免地会带来污染物的产生,如果不能有效控制化工排放污染物,温室效应问题会更加严重。本文对绿色化工技术在精细化工中的有效应用进行研究,降低工业废气污染物排放量,维护生态环境平衡。 相似文献
22.
为了提升高校实验数据处理水平,高校实验室的相关建设工作已经步入正轨,但层出不穷的信息安全问题也向高校实验室计算机网络维护工作提出了新的挑战。文章从现阶段高校实验室计算机网络的相关建设工作出发,简要论述引发网络故障的具体原因,并对其诊断技术进行探讨。 相似文献
23.
本文结合HTH电路的复杂性等特征分析与实际应用现状,研究了HTH电路的具体检测技术方法并对当前热点技术进行对比分析,探讨了HTH电路检测方法的技术发展趋势。 相似文献
24.
《Calphad》2020
This publication contains the thermodynamic results received by the drop calorimetry method. The experiments were conducted for four different cross sections, at the temperature of 1080 K. The investigated alloys were as follows: (Ga0.75Li0.25)1-xGex, (Ge0.50Li0.50)1-xGax, (Ga0.50Li0.50)1-xGex, (Ga0.25Li0.75)1-xGex. The mixing enthalpy changes measured for all four cross sections of the Ga-Ge-Li system are characterized by negative deviations from the ideal solutions. The Muggianu model with the ternary interaction parameters was applied to elaborate the experimental data of the mixing enthalpy change with the use of the optimized thermodynamic parameters of the binary systems available in the literature. 相似文献
25.
本文对国内外的电视技术发展现状进行了充分的研究和分析,并对超高清电视系统的相关图像技术参数进行了分析和介绍。 相似文献
26.
Health information technology (IT) is a promising way to achieve safer medication management in the delivery of healthcare. However, human factors/ergonomics dictates that in order to make the complex, cognitive work of healthcare delivery safer, health IT must properly support human cognition. This means, for example, that new health IT must reduce, not increase, workload during safety-critical tasks. The present study was the first to quantitatively assess the short- and long-term impact of bar coded medication administration (BCMA) IT on nurses' mental workload as well as on perceived medication safety. One-hundred seventy registered nurses across 3 dissimilar clinical units at an academic, freestanding pediatric hospital in the Midwest US participated in surveys administered before, 3 months after, and 12 months after the hospital implemented BCMA. Nurses rated their external mental workload (interruptions, divided attention, being rushed) and internal mental workload (concentration, mental effort) during medication administration tasks as well as the likelihood of each of three medication safety events: medication administration errors, medication errors on the clinical unit, and clinical unit-level adverse drug events. Clinical unit differences were assessed. Findings generally confirmed the hypothesis that external but not internal mental workload was associated with the perceived likelihood of a medication safety event. Comparisons of mental workload from pre- to post-BCMA revealed statistically significant changes in the critical care unit only. Medication safety appeared to improve over the long term in the hematology/oncology unit only. In the critical care and medical/surgical units, medication safety exhibited short-term improvements that were eliminated over time. Changes in mental workload and medication safety, two classically microergonomic constructs, were deeply embedded in macroergonomic phenomena. These included the fit between the BCMA system and the nature of nursing work, the process of BCMA implementation, and BCMA interactions with concurrent changes occurring in the hospital. Findings raise questions about achieving sustainable performance improvement with health IT as well as the balance between micro- and macroergonomic approaches to studying technology change.Relevance to industryDesigners must consider how technology changes cognitive work, including mental workload. Hospitals and other implementers of technology must ensure that new technology fits its users, their tasks, and the context of use, which may entail tailoring implementation, for example, to specific clinical units. Evaluators must look over time to assess both changes in cognitive work and implementation issues. Healthcare practitioners must also recognize that new technology means a complex transformation to an already complex sociotechnical system, which calls for a macroergonomic approach to design and analysis. 相似文献
27.
Commercialization of technologies has attracted increasing attention over the past years due to its role in improving national competitiveness. Iran has not been an exception as the country's policy-makers have been actively engaged in crafting national policies to facilitate and promote commercialization of technologies. The popularity of the existing policies in this field, however, has not been properly researched. Our research, by following a survey study methodology, aims for the first time to address this gap. The study looks at popularity of governmental policies aimed at supporting commercialization of patented technologies in Iran, based on the careful study of 10 cases of successfully commercialized patented technologies in Iran. Our results indicate that the commercialization process of the studied patented technologies was very much affected by some company/technology-specific characteristics. The study shows that the two policy measures with the highest perceived popularity were the financial supports and the services offered by incubation centers. Our results also show that some of the existing supportive policy measures did not serve the intended purposes and some other measures need to be fine-tuned, as far as the studied cases are concerned, such as frequently held invention and innovation exhibitions and the government-supported media coverage. 相似文献
28.
Digital technology becomes more powerful, intelligent, pervasive and ubiquitous. Ethical aspects of this development have not yet drawn the appropriate attention of researchers and engineers. This paper presents an instrument that aims at measuring the individual ethical position with regard to the design and development of computer software. The development of the Epos tool was based on two data collections. The data of the first survey (n1 = 147 participants) were used to select items and to determine the factorial structure of the questionnaire. Results show that the Epos instrument reliably assesses peoples’ ethical opinion with respect to five central components: (1) regulation, (2) data privacy, (3) domain specific knowledge, (4) societal responsibility and (5) company responsibility. In the second survey, we determined the stability of the instruments factor structure by assessing a sample of n2?=?196 participants. A confirmatory factor analysis (CFA) supported the initial factor structure. Next steps and further implications are discussed regarding the final version of the questionnaire. 相似文献
29.
《Ceramics International》2022,48(17):24953-24964
30.
随着教育信息化技术的发展,线上线下混合式教学模式已成为一种趋势。为了解决非全日制研究生课堂教学召集困难、效果不佳等问题,提出了基于“互联网+虚拟仿真技术”的线上线下混合式教学模式。本文以控制工程专业学位研究生为例,结合《现代电气控制技术》课程,探讨了线上线下混合式教学实现途径、师生互动方法、项目驱动案例教学法以及电气控制系统虚拟仿真实验平台的构建方法,切实提升非全日制研究生的培养质量。 相似文献