全文获取类型
收费全文 | 1013篇 |
免费 | 52篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 15篇 |
化学工业 | 256篇 |
金属工艺 | 27篇 |
机械仪表 | 24篇 |
建筑科学 | 42篇 |
矿业工程 | 1篇 |
能源动力 | 40篇 |
轻工业 | 150篇 |
水利工程 | 11篇 |
石油天然气 | 2篇 |
无线电 | 40篇 |
一般工业技术 | 176篇 |
冶金工业 | 87篇 |
原子能技术 | 12篇 |
自动化技术 | 184篇 |
出版年
2023年 | 7篇 |
2022年 | 21篇 |
2021年 | 39篇 |
2020年 | 26篇 |
2019年 | 41篇 |
2018年 | 44篇 |
2017年 | 50篇 |
2016年 | 55篇 |
2015年 | 38篇 |
2014年 | 28篇 |
2013年 | 78篇 |
2012年 | 55篇 |
2011年 | 55篇 |
2010年 | 46篇 |
2009年 | 50篇 |
2008年 | 43篇 |
2007年 | 39篇 |
2006年 | 35篇 |
2005年 | 25篇 |
2004年 | 27篇 |
2003年 | 23篇 |
2002年 | 26篇 |
2001年 | 13篇 |
2000年 | 14篇 |
1999年 | 10篇 |
1998年 | 23篇 |
1997年 | 24篇 |
1996年 | 17篇 |
1995年 | 13篇 |
1994年 | 15篇 |
1993年 | 10篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1990年 | 6篇 |
1989年 | 12篇 |
1988年 | 5篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 4篇 |
1984年 | 2篇 |
1983年 | 4篇 |
1982年 | 5篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1979年 | 5篇 |
1978年 | 4篇 |
1977年 | 6篇 |
1976年 | 2篇 |
1975年 | 3篇 |
1968年 | 1篇 |
排序方式: 共有1067条查询结果,搜索用时 15 毫秒
11.
The three papers in this special section were originally presented at the IEEE INFOCOM 2006 conference in Barcelona. The augmented papers, which address issues in wireless networks and mobile computing, represent the high quality of research presented at the conference. 相似文献
12.
13.
Miguel A. Conde Ricardo Colomo-Palacios Francisco J. García-Peñalvo Xabier Larrucea 《Telematics and Informatics》2018,35(3):551-563
The Web of Data is an emerging research field that contributes to make better decisions because it gathers, combines and analyses different data sources available worldwide. Educational data is an interesting domain because it deals with the quality of the education itself and educational institutions which are common goals for every country. This paper is devoted to present how this idea has been used to improve a learning analytics tool. By means of this tool, teachers can perform teamwork competence assessment of a group of students taking into account how the individuals acquire the essential components of such competence. In this sense, authors use the Comprehensive Training Model of the Teamwork Competence in Engineering Domain (CTMTC) method to gather competence evidences and improve the system with a learning analytics tool to support the process. This tool is able to transform competence evidences and stores them in a competence ontology built upon ISO 10018 concepts. The final result is the production of educational results for the web of data. 相似文献
14.
Jose R. Infante Luis A. Villarreal Arturo Cisneros Ren D. Peralta Raúl G. Lpez María E. Trevio Jaime Wisniak 《应用聚合物科学杂志》1996,62(13):2311-2316
The assembly of a stirred tank reactor capable of precise reaction temperature control is described. The unit allows easy on-line determination of the thermal effect and calculation of heat transfer coefficients and heat capacities. Construction elements are standard, low cost, and high quality. Temperature control is achieved by a heating-cooling loop integrated to the reactor jacket and a cascade control procedure. An important feature of the equipment is the integration of the data acquisition system with the supervisory control system that allows the capability of an advanced strategy for process control and data acquisition. The capability of the reaction system is demonstrated for the microemulsion polymerization of vinyl acetate, by the use of batch and isothermal operational modes. The course of the reaction is followed on-line by the temperature variation of the jacket. Procedures are described for the calibration of the unit. The reactor developed is versatile, is easy to configure and extend, is low cost, and can compete advantageously with commercial reactor units such as the Mettler RC1. © 1996 John Wiley & Sons, Inc. 相似文献
15.
Arturo Lopez Quintela Mercedes Pazos Pellin Senen Paz Abuin 《Polymer Engineering and Science》1996,36(4):568-573
The kinetics of the reaction between trimethylolpropane (TMP) and epichlorohydrin (ECH) were studied. A mechanism is proposed which involves the synthesis of chlorohydrins, a previous stage which then leads to epoxy resin formation. From this mechanism a set of three coupled non-linear differential equations, (each equation corresponds to each chlorohydrin) was derived and numerical solutions were obtained using a Monte-Carlo method. The concentrations of chlorohydrins determined by this method (41.7, 35.7, and 22.5%) compare well with the experimental GPC results (42.7, 34.7, and 22.6%). The corresponding rate constants for the formation of the chlorohydrins were obtained. 相似文献
16.
Jorge Espinosa-Espinosa Anchel Gonzlez-Barriga Arturo Lpez-Castel Rubn Artero 《International journal of molecular sciences》2022,23(3)
Omics studies are crucial to improve our understanding of myotonic dystrophy type 1 (DM1), the most common muscular dystrophy in adults. Employing tissue samples and cell lines derived from patients and animal models, omics approaches have revealed the myriad alterations in gene and microRNA expression, alternative splicing, 3′ polyadenylation, CpG methylation, and proteins levels, among others, that contribute to this complex multisystem disease. In addition, omics characterization of drug candidate treatment experiments provides crucial insight into the degree of therapeutic rescue and off-target effects that can be achieved. Finally, several innovative technologies such as single-cell sequencing and artificial intelligence will have a significant impact on future DM1 research. 相似文献
17.
Nischel Maheswaraiah Alvaro V. Sandate Arturo Bronson 《International Journal of Applied Ceramic Technology》2013,10(2):234-244
A Zr–Si liquid reacted with B4C in a graphite enclosure was configured to control the oxygen potential (10?45 kPa) to form a ZrB2 / ZrC / Zr – Si ceramic composite. The graphite enclosure was placed in a temperature gradient with the hot zone at >2133 K to react Zr – Si with B4C and with the opposite end approximating 933–1000 K at the position of an aluminum melt. A ZrB2 / ZrC / Zr – Si composite forms with the scanning‐electron microscope (SEM), microstructures showing rectangular ZrB2 precipitates and hexagonally shaped ZrC precipitates embedded in a Zr – Si matrix. 相似文献
18.
Donoso-Bravo A Mailier J Martin C Rodríguez J Aceves-Lara CA Vande Wouwer A 《Water research》2011,45(17):5347-5364
Anaerobic digestion enables waste (water) treatment and energy production in the form of biogas. The successful implementation of this process has lead to an increasing interest worldwide. However, anaerobic digestion is a complex biological process, where hundreds of microbial populations are involved, and whose start-up and operation are delicate issues. In order to better understand the process dynamics and to optimize the operating conditions, the availability of dynamic models is of paramount importance. Such models have to be inferred from prior knowledge and experimental data collected from real plants. Modeling and parameter identification are vast subjects, offering a realm of approaches and methods, which can be difficult to fully understand by scientists and engineers dedicated to the plant operation and improvements. This review article discusses existing modeling frameworks and methodologies for parameter estimation and model validation in the field of anaerobic digestion processes. The point of view is pragmatic, intentionally focusing on simple but efficient methods. 相似文献
19.
Martín Caldera Villalobos Miriam Martins Alho Jesús García Serrano Giaan Arturo Álvarez Romero Ana M. Herrera González 《应用聚合物科学杂志》2019,136(29):47790
Heterocyclic compounds are well known for their biological activity and coordination properties. Some heterocyclic compounds have been employed in the stabilization against coalescence of metallic nanoparticles in colloidal solutions, for example, tetrazole, triazole, and pyrazole. The aim of this work is to design new polyelectrolytes with heterocyclic pendant groups useful as reducing agents of Au3+ and as stabilizing agents for the synthesis of colloidal Au nanoparticles. Thus, polyelectrolytes with thiosemicarbazone and 1,3,4-thiadiazole pendant groups were used as reducing agents of Au3+ ions and stabilizing agents of Au nanoparticles. The voltammetry study of the polyelectrolytes showed that one with thiosemicarbazone pendant groups is the better reducing agent than polyelectrolytes with heterocyclic pendant groups. The polyelectrolytes can control the growth of the nanoparticles, obtaining structures with an average size of 9 nm. In this study, it was concluded that the nature of the heterocyclic group does not have an effect on the shape of nanoparticles and quasi-spherical nanoparticles were obtained with all polyelectrolytes. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47790. 相似文献
20.
Hierarchical micro-nanostructured albite-based glass-ceramic for high dielectric strength insulators
V. Fuertes M.J. Cabrera J. Seores D. Muñoz J.F. Fernández E. Enríquez 《Journal of the European Ceramic Society》2018,38(7):2759-2766
A novel glass-ceramic material based on albite type Na-rich feldspar has been synthesized by conventional ceramic process. High crystallinity, >94%?Vol.% is obtained by fast sintering which allows energy saving processing. Albite is the main crystalline phase and tetragonal SiO2 is a secondary phase. Electrical properties were examined by complex impedance, DC measurements, and dielectric breakdown test. Dielectric characterization shows a non-Debye type dielectric behavior with low dielectric constant, 4.6 at 1?MHz, low dielectric losses, (~10?3 at 1?MHz, and a large dielectric strength, ~60?kV/mm), that it is the largest value reported in ceramic insulators. Those dielectric properties are attained by the low glassy phase content in the samples and their unique micro-nanostructure. All these properties make this novel material a very promising candidate in the market of ceramic electrical insulator, highlighting for high-voltage applications. 相似文献