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251.
We report results from an experiment to compare the fault detection effectiveness of mutation, its variants and the all-uses data flow criteria. Adequate test sets were generated randomly, as opposed to by human testers as in some previous studies. We view our results in the light of those from earlier studies comparing mutation with path-oriented testing strategies. We identify and discuss factors that one might consider while evaluating an adequacy criterion for use in practice. Results from our experiments strengthen a hypothesis that an adequacy criterion based on one of the two variants of mutation has superior fault detection effectiveness than that of the all-uses criterion. 相似文献
252.
Alternative methods to describe water quality using an aggregate index consisting of subindices for individual water quality variables are examined. Most aggregation methods suffer from three shortcomings: Ambiguity, eclipsing, and rigidity. Ambiguity problems exist when all the subindices indicate acceptable water quality for a given use, but the aggregated index does not. Eclipsing problems exist when the aggregated index fails to reflect poor water quality of one or more water quality variables. Rigidity problems exist when additional variables are included in the index to address specific water quality concerns, but the faulty aggregation function might artificially reduce the value of the water quality index such that it does not accurately reflect the true water quality. As the number of water quality variables increases, the magnitude of the aggregated index decreases raising the issue of ambiguity again. The writers developed a mathematical formulation for aggregate indices that avoids the problems of ambiguity, eclipsing, and rigidity with respect to the number of water quality variables required to be aggregated in a given index. 相似文献
253.
Kondavitee Girija Sravani Rao K. Srinivasa Suman M. Pravallika B. Annapurna K. Sravani Vaishnavi G. Ramya K. Ruth Aditya M. 《SILICON》2023,15(5):2199-2209
Silicon - This paper presents the design and simulations of 5 nm HEMT. The analysis of analog parameters, electrical parameters and the RF performance of the 5 nm HEMT has been... 相似文献
254.
The interfacial microstructure of electroless Ni-P/Sn-3.5Ag solder joints was investigated after reflow and high-temperature
solid-state aging to understand its interdependent growth mechanism and related kinetics of intermetallic compounds (IMCs)
at the interface. The reflow and aging results showed that mainly three IMC layers, Ni3Sn4, Ni2SnP, and Ni3P, formed during the soldering reaction. It was found that the Ni3Sn4 and Ni3P layers grow predominantly as long as the electroless Ni-P layer is present; however, once the Ni-P layer is fully consumed,
the Ni2SnP layer grows rapidly at the expense of the Ni3P layer. A transition in the Ni3Sn4 morphology from needle and chunky shape to scallop shape was observed after the solid-state aging of reflowed samples. The
kinetics data obtained from the growth of compound layers in the aged samples revealed that initially the growth of the Ni2SnP layer is controlled by diffusion, and subsequently by the rate of reaction after the Ni-P metallization is fully consumed.
It was found that complete transformation of the electroless Ni-P layer into a Ni3P layer results in the rapid growth of the Ni2SnP layer due to the dominating reaction of Sn with Ni3P. The apparent activation energies for the growth of Ni3Sn4, Ni2SnP, and Ni3P compound layers were found to be 98.9 kJ/mol, 42.2 kJ/mol, and 94.3 kJ/mol, respectively. 相似文献
255.
Theoretical error rate performance of wireless communication systems are usually determined assuming that the perfect channel
state information (CSI) is available at the receiver. However, in actual practice, the channel gains at the receiver are obtained
via using some channel estimation (CE) techniques. Due to inherent presence of noise, the CE is not perfect resulting in the
performance degradation. In this paper, we evaluate the error rate performance of an uplink multicarrier code-division multiple-access
(MC-CDMA) system, considering different modulation techniques, where CE is performed using pilot symbol assisted (PSA) minimum
mean-square error (MMSE) CE technique. The symbol error rate (SER) analysis of an uplink MC-CDMA system using multiuser detection
techniques, such as MMSE and zero forcing (ZF), is presented under imperfect CE. Simulated results for SER are also shown
to confirm the accuracy of the analytically derived results. 相似文献
256.
Water Distribution System suffers from leakages causing social and economic costs. There is need of platform to manage water distribution system more efficiently by detecting, localizing and controlling the leakages even before or as soon as they occur, ensuring quality water services to the consumers. Since last two decades, high efforts have been made by researchers for the development of efficient leakage management techniques for reduction of water losses in distribution system. This paper provides a comprehensive analysis on leakage management techniques covering three aspects: leakage assessment, leakage detection and leakage control, with an objective to identify present challenges and future scope in their respected field. Role of smart water technologies for efficient leakages management in pipeline network is also examined and discussed. Conclusion is drawn regarding current leakage management techniques and proposals for future work and existing challenges are also outlined. 相似文献
257.
Polymeric siRNA delivery vectors: knocking down cancers with polymeric‐based gene delivery systems
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Aditya Ardana Andrew K. Whittaker Nigel A.J. McMillan Kristofer J. Thurecht 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2015,90(7):1196-1208
One of the most promising routes for cancer therapy that has evolved over the previous decade is the use of small‐interfering RNA (siRNA) as a means of switching off genes that are responsible for tumour development. However, while siRNA and gene/antisense therapies provide alternatives to conventional chemotherapies, significant hurdles related to the delivery and efficacy of treatment must still be overcome before this technology can be used as an effective treatment for cancer and other diseases. This review highlights the issues associated with siRNA therapy in vivo, and describes the various approaches that are being explored using polymers as delivery vectors. In particular, the review focuses on targeted delivery as a means of improving efficacy of the gene therapy. © 2014 Society of Chemical Industry 相似文献
258.
Thappa Sahil Chauhan Aditya Anand Y. Anand S. 《Clean Technologies and Environmental Policy》2021,23(10):2861-2881
Clean Technologies and Environmental Policy - This paper particularly aims to highlight the necessity of optimal geometrical design considerations of a parabolic trough collector (PTC)-mounted... 相似文献
259.
Rachel Cook Hongyan Ma Monday Okoronkwo Gaurav Sant Aditya Kumar 《Journal of the American Ceramic Society》2021,104(4):1831-1840
The hydration of the two most reactive phases of ordinary Portland cement (OPC), tricalcium silicate (C3S), and tricalcium aluminate (C3A) is successfully halted when the activity of water () falls below critical thresholds of 0.70 and 0.45, respectively. It has been established that the reduction in relative humidity (RH) and suppresses the hydration of all anhydrous phases in OPC, including less explored phases like dicalcium silicate, that is, belite (β-C2S). However, the degree of suppression, that is, the critical threshold, for β-C2S, standalone has yet to be established. This study utilizes isothermal microcalorimetry and X-ray diffraction techniques to elucidate the influence of on the hydration of -C2S suspensions via incremental replacements of water with isopropanol (IPA). Experimentally, this study shows that with increasing IPA replacements, hydration is increasingly suppressed until eventually brought to a halt at a critical threshold of approximately 27.7% IPA on a weight basis (wt.%IPA). From thermodynamic estimations, the exact critical threshold and solubility product constant of -C2S () are established as 0.913 and 10−12.68, respectively. This study enables enhanced understanding of β-C2S reactivity and provides thermodynamic parameters during the hydration of β-C2S-containing cementitious systems such as OPC-based and calcium aluminate-based systems. 相似文献
260.
Multimedia Tools and Applications - Image up-scaling employs various polynomial interpolation schemes for their reduced computational complexity and suitability for various real-time applications.... 相似文献