全文获取类型
收费全文 | 170篇 |
免费 | 31篇 |
专业分类
电工技术 | 4篇 |
化学工业 | 44篇 |
金属工艺 | 7篇 |
机械仪表 | 15篇 |
建筑科学 | 2篇 |
能源动力 | 2篇 |
轻工业 | 43篇 |
无线电 | 31篇 |
一般工业技术 | 35篇 |
冶金工业 | 3篇 |
原子能技术 | 2篇 |
自动化技术 | 13篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 4篇 |
2021年 | 5篇 |
2020年 | 5篇 |
2019年 | 8篇 |
2018年 | 11篇 |
2017年 | 11篇 |
2016年 | 16篇 |
2015年 | 10篇 |
2014年 | 6篇 |
2013年 | 10篇 |
2012年 | 10篇 |
2011年 | 14篇 |
2010年 | 9篇 |
2009年 | 6篇 |
2008年 | 5篇 |
2007年 | 9篇 |
2006年 | 2篇 |
2005年 | 10篇 |
2004年 | 3篇 |
2003年 | 3篇 |
2002年 | 6篇 |
2001年 | 4篇 |
2000年 | 9篇 |
1999年 | 6篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1996年 | 2篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1989年 | 3篇 |
排序方式: 共有201条查询结果,搜索用时 31 毫秒
21.
Organohalide Perovskites: Real‐Time Observation of Order‐Disorder Transformation of Organic Cations Induced Phase Transition and Anomalous Photoluminescence in Hybrid Perovskites (Adv. Mater. 22/2018)
下载免费PDF全文
![点击此处可从《Advanced materials (Deerfield Beach, Fla.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
22.
Kayeon Keum Jung Wook Kim Soo Yeong Hong Jeong Gon Son Sang-Soo Lee Jeong Sook Ha 《Advanced materials (Deerfield Beach, Fla.)》2020,32(51):2002180
With the miniaturization of personal wearable electronics, considerable effort has been expended to develop high-performance flexible/stretchable energy storage devices for powering integrated active devices. Supercapacitors can fulfill this role owing to their simple structures, high power density, and cyclic stability. Moreover, a high electrochemical performance can be achieved with flexible/stretchable supercapacitors, whose applications can be expanded through the introduction of additional novel functionalities. Here, recent advances in and future prospects for flexible/stretchable supercapacitors with innate functionalities are covered, including biodegradability, self-healing, shape memory, energy harvesting, and electrochromic and temperature tolerance, which can contribute to reducing e-waste, ensuring device integrity and performance, enabling device self-charging following exposure to surrounding stimuli, displaying the charge status, and maintaining the performance under a wide range of temperatures. Finally, the challenges and perspectives of high-performance all-in-one wearable systems with integrated functional supercapacitors for future practical application are discussed. 相似文献
23.
Caroline Murawski Andreas Mischok Jonathan Booth Jothi Dinesh Kumar Emily Archer Laura Tropf Chang‐Min Keum Ya‐Li Deng Kou Yoshida Ifor D. W. Samuel Marcel Schubert Stefan R. Pulver Malte C. Gather 《Advanced materials (Deerfield Beach, Fla.)》2019,31(42)
Fluorescence imaging is an indispensable tool in biology, with applications ranging from single‐cell to whole‐animal studies and with live mapping of neuronal activity currently receiving particular attention. To enable fluorescence imaging at cellular scale in freely moving animals, miniaturized microscopes and lensless imagers are developed that can be implanted in a minimally invasive fashion; but the rigidity, size, and potential toxicity of the involved light sources remain a challenge. Here, narrowband organic light‐emitting diodes (OLEDs) are developed and used for fluorescence imaging of live cells and for mapping of neuronal activity in Drosophila melanogaster via genetically encoded Ca2+ indicators. In order to avoid spectral overlap with fluorescence from the sample, distributed Bragg reflectors are integrated onto the OLEDs to block their long‐wavelength emission tail, which enables an image contrast comparable to conventional, much bulkier mercury light sources. As OLEDs can be fabricated on mechanically flexible substrates and structured into arrays of cell‐sized pixels, this work opens a new pathway for the development of implantable light sources that enable functional imaging and sensing in freely moving animals. 相似文献
24.
Kinetic models of grafting maleic anhydride (MAH) and methyl methacrylate (MMA) on polypropylene (PP) were developed for screw extrusion. However, the kinetic models were insufficient to explain the grafting reactions along the length of modular co‐rotating twin screw extruders because the rheological properties and the residence time of PP changed owing to degradation of PP during the grafting reaction. In order to model this system for a modular co‐rotating twin screw extruder, the kinetic model of grafting reaction and models for degradation of PP were combined with fluid mechanics and heat transfer. Given the geometrical configurations of the screw, the operating conditions, and the physical properties of the polypropylene, the simulations predicted variation of molecular weight and mean residence time due to degradation of PP. The weight percent of grafted MAH or MMA on PP profiles along the screw axis was also calculated in the simulation. These predictions were compared with experimental data for various operating conditions. J. VINYL. ADDIT. TECHNOL. 11:143–149, 2005. © 2005 Society of Plastics Engineers. 相似文献
25.
Suk Lee Asok Ray Keum Shik Hong Joongsun Yoon Myung Chul Han 《Journal of Mechanical Science and Technology》1995,9(3):269-285
Performance management of communication networks is critical for speed, reliability, and flexibility of information exchange between different components, subsystems, and sectors (e.g., factory, engineering design, and administration) of production process organizations in the environment of Computer Integrated Manufacturing (CIM). The objective is to improve the efficiency in handling various types of messages, e.g., control signals, sensor data and production orders, by on-line adjustment of the parameters of the network protocol. This paper presents conceptual design, development, and implementation of a performance management procedure for CIM applications. The performance management algorithm is formulated using the concepts of: (i) perturbation analysis of discrete event dynamic systems; (ii) stochastic approximation; and (iii) learning automata. The performance management procedure has been tested via emulation on a network testbed that is based on the Manufacturing Automation Protocol (MAP). The conceptual design presented in this paper offers a step forward to bridging the gap between management standards and users' demands for efficient network operations since most standards such as ISO and IEEE address only the architecture, services, and interfaces for network management. The proposed concept for performance management can also be used as a general framework to assist design, operation, and management of flexible manufacturing systems. 相似文献
26.
Comparative Study of Tocopherol Contents and Fatty Acids Composition in Twenty Almond Cultivars of Afghanistan
下载免费PDF全文
![点击此处可从《Journal of the American Oil Chemists](/ch/ext_images/free.gif)
Ahmad Jawid Zamany Ghulam Rasoul Samadi Doo Hwan Kim Young-Soo Keum Ramesh Kumar Saini 《Journal of the American Oil Chemists' Society》2017,94(6):805-817
Afghanistan is the fourth largest producer of almonds in the world producing 78 native and 6 imported cultivars. However, till date, there have been no comprehensive data on nutrient profiles of the native cultivars. Thus, in the present investigation, tocopherol contents and fatty acid composition from the kernels of 20 selected native almond cultivars of Afghanistan were analyzed. The ranges of variability for the studied nutrients were similar to those already reported for almonds grown in other countries, such as 47.8–66.1% of total lipids (fresh weight basis), 62.54–81.57% of oleic acid in the total lipids, and 139.1–355.0 μg/g α-tocopherol in kernels. With respect to cultivars, significantly (p < 0.05) high content of total lipids were recorded in ‘Belabai’ and ‘Sattarbai’ (Afghan grade), oleic acid in ‘Khairodini’ and of α-tocopherol in ‘Khairodini-161 Samangan’ and ‘Belabai’ cultivars. Kernels from these cultivars can be used for nutrient dense food formulations. Daily consumption of 50 g almonds is sufficient to meet the RDA of α-tocopherol (15 mg/day), considering the average 300 μg/g of α-tocopherol in Afghan almonds. Also, these nutrient rich cultivars can be used in almond breeding programs globally, to focus on improving kernel oil composition and nutrient contents. 相似文献
27.
A New Class of Renewable Thermoplastics with Extraordinary Performance from Nanostructured Lignin‐Elastomers
下载免费PDF全文
![点击此处可从《Advanced functional materials》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Chau D. Tran Jihua Chen Jong K. Keum Amit K. Naskar 《Advanced functional materials》2016,26(16):2677-2685
A new class of thermoplastic elastomers has been created by introducing nanoscale‐dispersed lignin (a biomass‐derived phenolic oligomer) into nitrile rubber. Temperature‐induced controlled miscibility between the lignin and the rubber during high shear melt‐phase synthesis allows tuning the material's morphology and performance. The sustainable product has unprecedented yield stress (15–45 MPa), strain hardens at large deformation, and has outstanding recyclability. The multiphase polymers developed from an equal‐mass mixture of a melt‐stable lignin fraction and nitrile rubber with optimal acrylonitrile content, using the method described here, show 5–100 nm lignin lamellae with a high‐modulus rubbery interphase. Molded or printed elastomeric products prepared from the lignin‐nitrile material offer an additional revenue stream to pulping mills and biorefineries. 相似文献
28.
29.
30.