全文获取类型
收费全文 | 602篇 |
免费 | 21篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 7篇 |
化学工业 | 133篇 |
金属工艺 | 19篇 |
机械仪表 | 18篇 |
建筑科学 | 5篇 |
能源动力 | 27篇 |
轻工业 | 42篇 |
水利工程 | 2篇 |
石油天然气 | 3篇 |
无线电 | 63篇 |
一般工业技术 | 189篇 |
冶金工业 | 42篇 |
原子能技术 | 8篇 |
自动化技术 | 67篇 |
出版年
2023年 | 6篇 |
2022年 | 9篇 |
2021年 | 22篇 |
2020年 | 6篇 |
2019年 | 16篇 |
2018年 | 17篇 |
2017年 | 15篇 |
2016年 | 18篇 |
2015年 | 19篇 |
2014年 | 26篇 |
2013年 | 42篇 |
2012年 | 27篇 |
2011年 | 42篇 |
2010年 | 41篇 |
2009年 | 37篇 |
2008年 | 33篇 |
2007年 | 32篇 |
2006年 | 17篇 |
2005年 | 20篇 |
2004年 | 14篇 |
2003年 | 13篇 |
2002年 | 9篇 |
2001年 | 7篇 |
2000年 | 6篇 |
1999年 | 7篇 |
1998年 | 13篇 |
1997年 | 11篇 |
1996年 | 8篇 |
1995年 | 8篇 |
1994年 | 8篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1990年 | 6篇 |
1989年 | 7篇 |
1988年 | 2篇 |
1987年 | 5篇 |
1986年 | 9篇 |
1985年 | 3篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1976年 | 3篇 |
1973年 | 2篇 |
1971年 | 1篇 |
排序方式: 共有625条查询结果,搜索用时 15 毫秒
71.
Gold nanoparticles of triangular morphology possess interesting optical properties with potential application in medicine and infrared absorbing coatings, however, little is known about conditions that favor their growth. In this paper, we have reinvestigated a time-tested recipe for the formation of gold nanospheres by citrate reduction of aqueous gold ions under boiling conditions (Turkevich recipe). Our principle findings are that gold nanotriangle formation is kinetically controlled and is highly favored at low temperatures. Furthermore, the presence of chloride ions from the precursor chloroaurate ions plays a major role in promoting the growth of <111> oriented triangular/truncated triangular particles. The presence of bromide and iodide ions that possess the ability to replace surface-bound chloride ions inhibits triangle formation to varying degrees. 相似文献
72.
Senapati S Ahmad A Khan MI Sastry M Kumar R 《Small (Weinheim an der Bergstrasse, Germany)》2005,1(5):517-520
73.
An enhanced hybrid scheme of wavelength reservation for dynamic wavelength routed optical networks is proposed. The performance of a newly introduced composite-two-phase reservation protocol (C2P-RP) is evaluated and compared with the existing hybrid reservation protocol. By offering connection requests an enhanced scope of finding an end-to-end available wavelength, the C2P-RP scheme shows improved connection-request blocking performance. 相似文献
74.
Guillermo Talavera Murali Jayapala Jordi Carrabina Francky Catthoor 《Journal of Signal Processing Systems》2008,53(3):271-284
Nowadays embedded systems are growing at an impressive rate and provide more and more sophisticated applications characterized
by having a complex array index manipulation and a large number of data accesses. Those applications require high performance
specific computation that general purpose processors can not deliver at a reasonable energy consumption. Very long instruction
word architectures seem a good solution providing enough computational performance at low power with the required programmability
to speed up the time to market. Those architectures rely on compiler effort to exploit the available instruction and data
parallelism to keep the data path busy all the time. With the density of transistors doubling each 18 months, more and more
sophisticated architectures with a high number of computational resources running in parallel are emerging. With this increasing
parallel computation, the access to data is becoming the main bottleneck that limits the available parallelism. To alleviate
this problem, in current embedded architectures, a special unit works in parallel with the main computing elements to ensure
efficient feed and storage of the data: the address generator unit, which comes in many flavors. Future architectures will
have to deal with enormous memory bandwidth in distributed memories and the development of address generators units will be
crucial for effective next generation of embedded processors where global trade-offs between reaction-time, bandwidth, energy
and area must be achieved. This paper provides a survey of methods and techniques that optimize the address generation process
for embedded systems, explaining current research trends and needs for future.
相似文献
Francky CatthoorEmail: |
75.
A survey was conducted in south India to find out the amount of chromium (Cr) present in marketable black tea. Before assessing the Cr content in black tea, the Cr content in the green shoots was assessed, in order to know the Cr contamination after completion of the manufacturing process. Samples of black tea manufactured by CTC (Crush, Tear and Curl) and Orthodox processes were collected and analysed for Cr content. The study revealed that the content of Cr was high in CTC-manufactured black tea, which involved the use of stainless steel rollers. A pilot scale experiment was carried out, using newly sharpened rollers, and the black tea samples prepared were analysed for Cr content. A similar study was carried out in a commercial factory and samples analysed for Cr for one month. The study confirmed that Cr content was positively correlated to the sharpening of CTC rollers used for manufacturing. 相似文献
76.
Krishna Ch. Murali ViswanathaReddy G. Souayeh Basma Raju C. S. K. Rahimi-Gorji Mohammad Raju S. Suresh Kumar 《Microsystem Technologies》2019,25(10):3735-3746
Microsystem Technologies - A theoretical study on the effect of magnetohydrodynamic field on the classical Blasius and Sakiadis flows of heat transfer characteristics with variable conditions and... 相似文献
77.
Venugopal Gopalakrishna-Remani Jay R. Brown Murali Shanker Micheal Hu 《Information & Management》2018,55(2):215-223
Timely reporting of rare infectious disease cases to the public health system, especially after identification at laboratories, is essential to initiate quick and effective public health response. To ensure that the public health reporting system is appropriately monitoring the rare infectious diseases under surveillance, it is recommended to have a regular assessment of timeliness, especially after the rare infectious case is confirmed. This study aimed to evaluate the timeliness of data reported to the Ohio Disease Reporting System (ODRS), a public health reporting system in Ohio, for managing rare infectious diseases. In a cross-sectional analysis of rare infectious disease reporting data in four local health jurisdictions (LHJs) in the state of Ohio, wide delays were found between various reporting steps, particularly when the laboratories were not using the electronic method of reporting, and the delay observed was mainly at the hospital level and at the LHJ level. This study highlights the supply chain nature of information transfer and calculates the delay at various interacting points of the information supply chain system. The results establish that a centralized approach with an electronic disease reporting system conveys information faster than traditional reporting channels (decentralized approach). Delays of the decentralized approach are isolated at various stakeholder levels and with respect to various types of rare infectious diseases for better understanding of the information supply chain system for managing rare infectious diseases. 相似文献
78.
Pushkar Dasika Debadarshini Samantaray Krishna Murali Nithin Abraham Kenji Watanbe Takashi Taniguchi N Ravishankar Kausik Majumdar 《Advanced functional materials》2021,31(13):2006278
The gate-all-around nanowire transistor, due to its extremely tight electrostatic control and vertical integration capability, is a highly promising candidate for sub-5 nm technology nodes. In particular, the junctionless nanowire transistors are highly scalable with reduced variability due to avoidance of steep source/drain junction formation by ion implantation. Here a dual-gated junctionless nanowire p-type field effect transistor is demonstrated using tellurium nanowire as the channel. The dangling-bond-free surface due to the unique helical crystal structure of the nanowire, coupled with an integration of dangling-bond-free, high quality hBN gate dielectric, allows for a phonon-limited field effect hole mobility of 570 cm2 V−1 s−1 at 270 K, which is well above state-of-the-art strained Si hole mobility. By lowering the temperature, the mobility increases to 1390 cm2 V−1 s−1 and becomes primarily limited by Coulomb scattering. The combination of an electron affinity of ≈ 4 eV and a small bandgap of tellurium provides zero Schottky barrier height for hole injection at the metal-contact interface, which is remarkable for reduction of contact resistance in a highly scaled transistor. Exploiting these properties, coupled with the dual-gated operation, we achieve a high drive current of 216 μA μm−1 while maintaining an on-off ratio in excess of 2 × 104. The findings have intriguing prospects for alternate channel material based next-generation electronics. 相似文献
79.
Xiaowu Tang G. Murali Hyungjin Lee Seongmin Park Seongeun Lee Sun Moo Oh Jihoon Lee Tae Yun Ko Chong Min Koo Yong Jin Jeong Tae Kyu An Insik In Se Hyun Kim 《Advanced functional materials》2021,31(29):2010897
MXenes are interesting 2D materials that have been considered as attractive frontier materials for potential applications in the fields of energy and electronic devices due to their excellent optoelectronic properties including metallic conductivity and high optical transparency. However, it is still challenging to achieve compatibility for the as-synthesized MXene nanosheets with simple solution-deposition and patterning processes because of their limited solubility in many solvents. Here, a promising strategy is developed for obtaining alcohol-dispersible MXene nanosheets suitable for all-printed electronics while enhancing their electrical conductivity. This strategy includes a trifluoroacetic acid treatment—applied in order to contribute to the modification of intercalants between the MXene nanosheets—and achieves long-term dispersion of the MXene in alcoholic media and balanced jetting conditions during the electrohydrodynamic printing process. Furthermore, the high conductivity levels of the treated MXenes allow their printed patterns to be applied as gate and source/drain electrodes in all-printed logic circuits, displaying good and robust operation in transistors, inverters, and NAND, and NOR logic gates. This study provides a promising approach for modifying MXene nanosheets with the purpose of achieving desirable properties suitable for large-area printing processes, suggesting the feasibility of using MXene in practical applications involving all-printed electronics. 相似文献
80.
The Starch–Casein‐based edible films containing with or without neem (Melia azadirachta) extract was prepared. The neem based free films were also heat pressed and all of them were assessed for inhibition of pathogenic organisms namely E. coli, Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Pseudomonas spp., and Salmonella, using disc diffusion assay. The Glass‐transition temperature (Tg) and thermal properties of the films were determined with the help of DSC and DMA. Tensile strength (TS), elongation at break (EAB), water vapor transmission rate (WVTR), and oxygen transmission rate (OTR) of the films were also determined. Incorporation of neem extract to edible film did not affect any of the physical properties except microbial, and the films were effective in inhibiting the growth of pathogens, since the inhibition zones varied from 15 mm as large as 24 mm. However, the heat‐pressed films containing neem extract led higher the Tg, TS, and modulus, while the EAB was marginally affected, indicating the toughening of the film and as expected, the heat pressing of films decreased the WVTR and marginally affected OTR. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3948–3954, 2006 相似文献