全文获取类型
收费全文 | 561篇 |
免费 | 33篇 |
专业分类
电工技术 | 3篇 |
综合类 | 1篇 |
化学工业 | 131篇 |
金属工艺 | 9篇 |
机械仪表 | 12篇 |
建筑科学 | 17篇 |
矿业工程 | 2篇 |
能源动力 | 24篇 |
轻工业 | 88篇 |
水利工程 | 8篇 |
石油天然气 | 5篇 |
无线电 | 34篇 |
一般工业技术 | 81篇 |
冶金工业 | 99篇 |
原子能技术 | 5篇 |
自动化技术 | 75篇 |
出版年
2024年 | 2篇 |
2023年 | 5篇 |
2022年 | 14篇 |
2021年 | 30篇 |
2020年 | 15篇 |
2019年 | 23篇 |
2018年 | 21篇 |
2017年 | 16篇 |
2016年 | 14篇 |
2015年 | 18篇 |
2014年 | 22篇 |
2013年 | 28篇 |
2012年 | 31篇 |
2011年 | 41篇 |
2010年 | 24篇 |
2009年 | 22篇 |
2008年 | 24篇 |
2007年 | 20篇 |
2006年 | 15篇 |
2005年 | 19篇 |
2004年 | 13篇 |
2003年 | 10篇 |
2002年 | 12篇 |
2001年 | 13篇 |
2000年 | 1篇 |
1999年 | 9篇 |
1998年 | 34篇 |
1997年 | 22篇 |
1996年 | 11篇 |
1995年 | 12篇 |
1994年 | 10篇 |
1993年 | 7篇 |
1992年 | 2篇 |
1991年 | 7篇 |
1990年 | 2篇 |
1989年 | 3篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 3篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 4篇 |
1976年 | 3篇 |
1973年 | 2篇 |
排序方式: 共有594条查询结果,搜索用时 15 毫秒
91.
Haxhibeqiri Jetmir Jiao Xianjun Municio Esteban Marquez-Barja Johann M. Moerman Ingrid Hoebeke Jeroen 《Wireless Personal Communications》2021,121(2):1255-1271
Wireless Personal Communications - Private professional environments such as manufacturing industry, warehouses, hospitals, airports, among others, increasingly rely on end-to-end connected... 相似文献
92.
Optimization of properties in a rubber compound containing a ternary polymer blend using response surface methodology
下载免费PDF全文
![点击此处可从《应用聚合物科学杂志》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Pablo E. Salvatori Gastón Sánchez Aldo Lombardi Esteban Nicocia Santiago A. Bortolato Carlos E. Boschetti 《应用聚合物科学杂志》2018,135(30)
In order to find the best combination of three synthetic rubbers, that is, styrene‐butadiene rubber (SBR) grade 1712, SBR grade 1721 and high‐1,4‐cis polybutadiene, that produce a compound with specific end‐use properties, a statistical experimental design is proposed in this work. The design consists of ten mixtures containing specific amounts of total styrene and BR content. A number of properties are tested in each mixture, selecting those related to requirements for the tread of a high performance tire: glass transition temperature (Tg), the ratio between the viscous modulus and the elastic modulus (tanδ@60 °C), Mooney viscosity, and the tensile properties. The values obtained for each property are fit to statistically significant models, obtaining the respective response surfaces. These are next used to define a desirable formulation with the optimal ratio of each rubber, and finally the optimized formulation is validated by comparing the experimental and predicted values for each modeled property. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46548. 相似文献
93.
94.
95.
A Esteban I Alía MJ Tobin A Gil F Gordo I Vallverdú L Blanch A Bonet A Vázquez R de Pablo A Torres MA de La Cal S Macías 《Canadian Metallurgical Quarterly》1999,159(2):512-518
The duration of spontaneous breathing trials before extubation has been set at 2 h in research studies, but the optimal duration is not known. We conducted a prospective, multicenter study involving 526 ventilator-supported patients considered ready for weaning, to compare clinical outcomes for trials of spontaneous breathing with target durations of 30 and 120 min. Of the 270 and 256 patients in the 30- and 120-min trial groups, respectively, 237 (87.8%) and 216 (84.8%), respectively, completed the trial without distress and were extubated (p = 0.32); 32 (13.5%) and 29 (13.4%), respectively, of these patients required reintubation within 48 h. The percentage of patients who remained extubated for 48 h after a spontaneous breathing trial did not differ in the 30- and 120-min trial groups (75.9% versus 73.0%, respectively, p = 0.43). The 30- and 120-min trial groups had similar within-unit mortality rates (13 and 9%, respectively) and in-hospital mortality rates (19 and 18%, respectively). Reintubation was required in 61 (13.5%) patients, and these patients had a higher mortality (20 of 61, 32.8%) than did patients who tolerated extubation (18 of 392, 4.6%) (p < 0.001). Neither measurements of respiratory frequency, heart rate, systolic blood pressure, and oxygen saturation during the trial, nor other functional measurements before the trial discriminated between patients who required reintubation from those who tolerated extubation. In conclusion, after a first trial of spontaneous breathing, successful extubation was achieved equally effectively with trials targeted to last 30 and 120 min. 相似文献
96.
This contribution reports on a study of the rheological behavior of Athabasca topped heavy oil as a prototype oil derived from western Canadian bitumen. Mixtures of crudes with additives such as pentane and toluene are studied. Data obtained using three different rheometers superpose rather well. Observed non-Newtonian behavior was successfully modeled by a simplified equation, derived from a model proposed by De Kee and Chan Man Fong (1994). Yield stress data were determined using a technique which does not involve extrapolation. Both yield stress as well as viscosity data obey Arrhenius type relations over the temperature range studied. 相似文献
97.
98.
99.
Iaki Ucar Marco Gramaglia Marco Fiore Zbigniew Smoreda Esteban Moro 《Journal of the Royal Society Interface》2021,18(185)
Reliable and timely information on socio-economic status and divides is critical to social and economic research and policing. Novel data sources from mobile communication platforms have enabled new cost-effective approaches and models to investigate social disparity, but their lack of interpretability, accuracy or scale has limited their relevance to date. We investigate the divide in digital mobile service usage with a large dataset of 3.7 billion time-stamped and geo-referenced mobile traffic records in a major European country, and find profound geographical unevenness in mobile service usage—especially on news, e-mail, social media consumption and audio/video streaming. We relate such diversity with income, educational attainment and inequality, and reveal how low-income or low-education areas are more likely to engage in video streaming or social media and less in news consumption, information searching, e-mail or audio streaming. The digital usage gap is so large that we can accurately infer the socio-economic status of a small area or even its Gini coefficient only from aggregated data traffic. Our results make the case for an inexpensive, privacy-preserving, real-time and scalable way to understand the digital usage divide and, in turn, poverty, unemployment or economic growth in our societies through mobile phone data. 相似文献
100.