全文获取类型
收费全文 | 1060篇 |
免费 | 72篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 10篇 |
化学工业 | 316篇 |
金属工艺 | 34篇 |
机械仪表 | 53篇 |
建筑科学 | 29篇 |
矿业工程 | 2篇 |
能源动力 | 62篇 |
轻工业 | 181篇 |
水利工程 | 3篇 |
石油天然气 | 8篇 |
无线电 | 75篇 |
一般工业技术 | 162篇 |
冶金工业 | 28篇 |
原子能技术 | 6篇 |
自动化技术 | 165篇 |
出版年
2024年 | 11篇 |
2023年 | 22篇 |
2022年 | 26篇 |
2021年 | 49篇 |
2020年 | 45篇 |
2019年 | 33篇 |
2018年 | 60篇 |
2017年 | 56篇 |
2016年 | 62篇 |
2015年 | 55篇 |
2014年 | 72篇 |
2013年 | 211篇 |
2012年 | 51篇 |
2011年 | 51篇 |
2010年 | 66篇 |
2009年 | 64篇 |
2008年 | 37篇 |
2007年 | 27篇 |
2006年 | 26篇 |
2005年 | 11篇 |
2004年 | 13篇 |
2003年 | 2篇 |
2002年 | 13篇 |
2001年 | 9篇 |
2000年 | 12篇 |
1999年 | 8篇 |
1998年 | 7篇 |
1997年 | 1篇 |
1996年 | 7篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1985年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有1134条查询结果,搜索用时 10 毫秒
91.
Thermally exfoliated graphene oxide reinforced fluorinated pentablock poly(l‐lactide‐co‐ε‐caprolactone) electrospun scaffolds: Insight into antimicrobial activity and biodegradation 下载免费PDF全文
Burcu Saner Okan Azucena Marset Jamal Seyyed Monfared Zanjani Pınar Akkus Sut Ozlem Sen Mustafa Çulha Yusuf Menceloglu 《应用聚合物科学杂志》2016,133(22)
Three‐dimensional fluorinated pentablock poly(l ‐lactide‐co‐ε‐caprolactone)‐based scaffolds were successfully produced by the incorporation of thermally exfoliated graphene oxide (TEGO) as an antimicrobial agent with an electrospinning technique. In a ring‐opening polymerization, the fluorinated groups in the middle of polymer backbone were attached with a perfluorinated reactive stabilizer having oxygen‐carrying ability. The fiber diameter and its morphologies were optimized through changes in TEGO amount, voltage, polymer concentration, and solvent type to obtain an ideal scaffold structure. Instead of the widely used graphene oxide synthesized by Hummer's method, TEGO sheets having a low amount of oxygen produced by thermal expansion were integrated into the fiber structure to investigate the effect of the oxygen functional groups of TEGO sheets on the degradation and antimicrobial activity of the scaffolds. There was no antimicrobial activity in TEGO‐reinforced scaffolds in the in vitro tests in contrast to the literature. This study confirmed that a low number of oxygen functional groups on the surface of TEGO restricted the antimicrobial activity of the fabricated composite scaffolds. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43490. 相似文献
92.
Hasan Çimen 《Advances in Engineering Software》2009,40(8):751-758
In this study, structured singular values are used in a different way from those commonly used in the robust control literature. It is shown that subject to conditions based on structured singular values, each local area controller can be designed independently. A MATLAB? program is developed to plot inverse structured singular values of multi input multi output (MIMO) system relative error matrix. This plot can be used to predict the stability of the global system with decentralised controller. Therefore decentralised controller design problem can be translated into an equivalent problem of decentralized controller design for a MIMO control system. 相似文献
93.
Synthesis and characterization of a Zr‐containing silicate‐based epoxy‐functional polymer nanocomposite system 下载免费PDF全文
As a continuation of efforts to explore the potential of certain types of polymer nanocomposites to be successful candidates as dental restoration/adhesion materials, a Zr‐containing and organically modified silicate‐based material system with epoxy functionality was prepared by use of a sol–gel synthesis method, and UV light‐ and visible light (VL)‐curing processes. Comparative influences of the synthesis and processing parameters on the mechanical, thermal, and microstructural/nanostructural properties of the system were detailed. Zr‐containing species proved to more effectively catalyze the epoxy polymerization/crosslinking reactions than those containing Ti. Incorporation of Zr into the nanocomposite network led to significantly advanced mechanical properties. An elastic (Young's) modulus value of 23 MPa was achieved. The system with relatively high Zr content was successfully obtained, which also had higher thermal stability. Overall observations and results suggested that Zr content, and the UV light‐ or VL‐curing process could be capitalized on to modify the structure, and to improve the final properties of these material systems, which indicated a prospective opportunity for this material system to be utilized in dental restoration/adhesion applications. POLYM. ENG. SCI., 55:792–798, 2015. © 2014 Society of Plastics Engineers 相似文献
94.
R&D project selection decision is very important in two ways. First, in many organizations, R&D budget represents huge investment. Project selection decisions could be thought with the strategic objectives and plans of the firm. Second, R&D projects' organizational returns are multidimensional in nature and risky in terms of projected outcome. Real options approach helps to calculate this risky side of the selection process. This paper considers that multidimensional side of the R&D project selection process. Another consideration is the vagueness in the evaluation process. The fuzzy analytic hierarchy process, which takes monetary (fuzzy real option value) and nonmonetary (capability, success probability, trends, etc.) criteria into account, is used to make this selection among alternative R&D projects. A real case study is given to illustrate the application of the proposed approach. © 2008 Wiley Periodicals, Inc. 相似文献
95.
Batch sequencing and cooperation 总被引:1,自引:0,他引:1
Game theoretic analysis of sequencing situations has been restricted to manufacturing systems which consist of machines that can process only one job at a time. However, in many manufacturing systems, operations are carried out by batch machines which can simultaneously process multiple jobs. This paper aims to extend the game theoretical approach to the cost allocation problems arising from sequencing situations on systems that consist of batch machines. To analyze the allocation problem at hand, it focusses on the existence of core elements, convexity, and the Shapley value. 相似文献
96.
Bit-level systolic arrays for modular multiplication 总被引:4,自引:0,他引:4
This paper presents bit-level cellular arrays implementing Blakley's algorithm for multiplication of twon-bit integers modulo anothern-bit integer. The semi-systolic version uses 3n(n+3) single-bit carry save adders and 2n copies of 3-bit carry look-ahead logic, and computes a pair of binary numbers (C, S) in 3n clock cycles such thatC+S[0, 2N). The carry look-ahead logic is used to estimate the sign of the partial product, which is needed during the reduction process. The final result in the correct range [0,N) can easily be obtained by computingC+S andC+S–N, and selecting the latter if it is positive; otherwise, the former is selected. We construct a localized process dependence graph of this algorithm, and introduce a systolic array containing 3nw simple adder cells. The latency of the systolic array is 6n+w–2, wherew=n/2. The systolic version does not require broadcast and can be used to efficiently compute several modular multiplications in a pipelined fashion, producing a result in every clock cycle. 相似文献
97.
Sükran Cakli Latif Taskaya Duygu Kisla Ufuk Çelik Can Altinel Ataman Asli Cadun Berna Kilinc Ramin Haji Maleki 《European Food Research and Technology》2005,220(5-6):526-530
Abstract Production of fish fingers was achieved by using fish species such as sardine (Sardina pilchardus, Walbaum, 1792), whiting (Merlangius merlangus, Linnaeus, 1758) and pike perch (Sander lucioperca, Linnaeus, 1758). Quality changes of battered fish patties during a period of 8 months at –18 °C were investigated. According to the results of microbiological and chemical analysis, fish fingers were found to be within acceptable limits during frozen storage for 8 months. However, sensory analysis showed that, at the end of the frozen storage, fish fingers made from sardine could not be consumed because of rancidity. 相似文献
98.
Ozone, which is also referred to as triatomic oxygen or trioxygen, is a naturally occurring inorganic molecule that consists of three oxygen atoms. Ozone has proven microbiological properties and, for this reason, it is extensively used in modern medical practices. Ozone is a powerful oxidant that demonstrates bactericide, virucide, and fungicide effects. The strong oxidation effect it produces results in the formation of highly reactive free radicals that have the capability to destroy microorganisms. Ozone has been proposed as a means of preventing caries, and existing research confirms that this form of therapy does have promising potential. However, very few clinical studies have examined the impact that ozone treatment can have on the management of caries lesions. This article presents a detailed literature review of existing peer-reviewed sources that have examined the role ozone plays in preventing and treating caries. 相似文献
99.
Nihal Menzi-Çetin Ecenaz Alemdağ Hakan Tüzün Merve Yıldız 《Universal Access in the Information Society》2017,16(1):151-160
Today websites are the tools most commonly used to access information. People with disabilities face difficulties accessing or using information, and the importance of website usability in their lives needs to be recognized. Visually impaired students need to be able to use university websites that inform them about the opportunities and events taking place on campus. This study aims to evaluate the usability of a university website by visually impaired students. In this research, six visually impaired students were interviewed. The assistive technologies they use, as well as the various web pages they wished to use unaided were identified. Following data collection, usability tests were conducted and satisfaction surveys were completed. The usability test was done with five visually impaired students. They were asked to think aloud while performing 11 tasks involving their university’s web pages, including the main page and the pages of student affairs, library and departments and then to accomplish these tasks. In this test, five tasks were not successfully completed by all students. According to the test results, finding final exam dates on the academic calendar posed major difficulties, and accessing the course schedule web page was the task that required the most time. The test results indicated the need for a search engine on each page, a text version for all pages, rearrangement of the web link sequences with tabs and more information about visuals. Suggestions related to the visually impaired students’ needs were offered. 相似文献