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排序方式: 共有498条查询结果,搜索用时 31 毫秒
1.
Highly Efficient Rapid Annealing of Thin Polar Polymer Film Ferroelectric Devices at Sub‐Glass Transition Temperature 下载免费PDF全文
Vasileia Georgiou Dmitry Veksler Jason T. Ryan Jason P. Campbell Pragya R. Shrestha Dimitris E. Ioannou Kin P. Cheung 《Advanced functional materials》2018,28(8)
An unexpected rapid anneal of electrically active defects in an ultrathin (15.5 nm) polar polyimide film at and below glass transition temperature (Tg) is reported. The polar polymer is the gate dielectric of a thin‐film‐transistor. Gate leakage current density (Jg) through the polymer initially increases with temperature, as expected, but decreases rapidly at Tg ? 60 °C. After ≈2 min at Tg, the leakage is reduced by nearly three orders of magnitude. A concomitant observation is that the drain current (Id)–gate voltage (Vg) hysteresis decreases with temperature, reaching zero at nearly the same temperature at which Jg collapses. As Jg drops further, the drain current hysteresis increases again but in the opposite direction. This combination strongly supports the interpretation of rapid defect annealing. 相似文献
2.
Feifei Li Haoqiang Ai Changmin Shi Kin Ho Lo Hui Pan 《International Journal of Hydrogen Energy》2021,46(24):12886-12896
Electrochemical CO2 reduction reaction (CO2RR) is an efficient way in the utilization of CO2. In this work, single transition-metal (TM) atom (TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn) anchored on two-dimensional (2D) Ti2CN2 are designed for CO2RR using density-functional-theory (DFT) calculation. We show that Ti2CN2 serves as an excellent substrate to support single atom catalysts (SACs), compared to Ti2CO2 and Ti2CF2. We find that the Sc, Ti and V supported on Ti2CN2 show high catalytic activities to produce CO with a low overpotential of 0.37, 0.27, and 0.23 eV, respectively. Differently, the Mn and Fe on Ti2CN2 are catalytically active for the production of HCOOH with a low overpotential of 0.32 and 0.43 eV, respectively. We further show that the negatively charged TM-Ti2CN2 can capture and activate CO2 more effectively, and the catalytic activity and selectivity can be significantly tuned by injecting extra electrons. 相似文献
3.
Aristides D. Tagalakis Vignesh Jayarajan Ruhina Maeshima Kin H. Ho Farhatullah Syed Lin-Ping Wu Ahmad M. Aldossary Mustafa M. Munye Talisa Mistry Olumide Kayode Ogunbiyi Arturo Sala Joseph F. Standing Seyed M. Moghimi Andrew W. Stoker Stephen L. Hart 《Advanced functional materials》2021,31(37):2104843
4.
Kin Kit Fong Inn Shi Tan Henry Chee Yew Foo Man Kee Lam Adrian Chiong Yuh Tiong Steven Lim 《中国化学工程学报》2021,33(5):297-305
The rising production of produced water from oilfields had been proven to bring detrimental environmental effects. In this study, an efficient, recyclable, and environmental-friendly reduced graphene oxide immobilized κ-Carrageenan hydrogel composite(κCa GO) was fabricated as an alternative sorbent for crude oil-in-water demulsification. Polyethyleneimine(PEI) was employed to form a stable hydrogel composite. The conditions for the immobilization of graphene oxide(GO) on PEI-modified κ-Carrageenan(κC) beads were optimized appropriately. An immobilization yield of 77% was attained at 2% PEI, 2 h immobilization activation time, and p H6.5. Moreover, the synthesized κCa GO is capable of demulsification with an average demulsification efficiency of 70%. It was found that the demulsification efficiency increases with salinity and κCa GO dosage, and it deteriorates under alkaline condition. These phenomena can be attributed to the interfacial interactions between κCa GO and the emulsion. Furthermore, the κCa GO can be recycled to use for up to six cycles without significant leaching and degradation. As such, the synthesized κCa GO could be further developed as a potential sorbent substitute for the separation of crude oil from produced water. 相似文献
5.
6.
Wai Kin Victor Chan & Charles J. Malmborg 《国际生产研究杂志》2013,51(14):4258-4272
The effectiveness of Monte Carlo simulation relative to intelligent search strategies for solving block layout problems is investigated. For testing purposes, 810 block layout problems are constructed to span a wide range of problem sizes, material flow variation levels, work centre space requirements distributions, and work centre shape distributions. Contrary to preliminary results reported in earlier studies, greedy search and simulated annealing consistently outperform Monte Carlo Simulation across the full range of test problems and sample sizes. This divergence is explained through a comparison based on probabilistic derivations between the proportion of good solutions sampled by the Monte Carlo method and those found by the heuristic search methods. Conditions for the superiority of either method are identified. Therefore, the current study complements earlier studies by providing analytical arguments and additional experimental evidence for the effectiveness of simple Monte Carlo method and intelligent search heuristics on solving layout problems. 相似文献
7.
Lei KF 《Recent patents on nanotechnology》2013,7(1):81-90
Microfluidic systems provide a total solution of biological and chemical analysis from the sample application to the display of the analysis results. A lot of developments on the point-of-care diagnostic applications have been reported and the commercial possibility is shown. To achieve sensitive and specific biological sensing, nanoparticles may provide a promising tool because they have similar length scale with the biomolecules. The nano-sensing technology suggests a molecular level detection of the biomolecules to pursue higher performance. In this review, recent developments and patents on the biological sensing using nanoparticles in microfluidic systems are discussed. An updated, systematic and rapid reference in the field of nano-biological sensing is provided. 相似文献
8.
Tadahiro Kin Takaya Kawagoe Shouhei Araki Yukinobu Watanabe 《Journal of Nuclear Science and Technology》2017,54(10):1123-1130
We conducted a feasibility study for producing a high-purity medical radioisotope 64Cu from natural zinc with accelerator-based neutrons. 64Cu isotopes were produced via the 64Zn(n,p) reaction. The accelerator-based neutrons were generated via the C(d,n) reaction using low-energy deuterons of 9 and 12 MeV on a 1-mm-thick carbon target. First, the production purity was estimated using the evaluated nuclear data library JENDL-4.0 and our previously measured thick target neutron yield. We found that even when natural zinc was used as the starting material, significantly high-purity 64Cu could be obtained. Next, irradiation experiments for producing 64Cu using natural zinc were conducted at Kyushu University Tandem Laboratory, with the amounts of 64Cu isotopes and other gamma-emission nuclides measured by a high-purity germanium detector. As a result, high-purity 64Cu isotopes of 1.11(49) × 100 and 3.70 (17) × 100 Bq/g/μC were produced with incident deuteron energies of 9 and 12 MeV, respectively. 相似文献
9.
In this paper, an improved EMD meta-learning rate-based model for gold price forecasting is proposed. First, we adopt the EMD method to divide the time series data into different subsets. Second, a back-propagation neural network model (BPNN) is used to function as the prediction model in our system. We update the online learning rate of BPNN instantly as well as the weight matrix. Finally, a rating method is used to identify the most suitable BPNN model for further prediction. The experiment results show that our system has a good forecasting performance. 相似文献
10.
This study reports a multifunctional electrode approach which directly implements electrokinetic enhancement on a self-assembled-monolayer-based electrochemical sensor for point-of-care diagnostics. Using urinary tract infections as a model system, we demonstrate that electrokinetic enhancement, which involves in situ stirring and heating, can enhance the sensitivity of the strain specific 16S rRNA hybridization assay for 1 order of magnitude and accelerate the time-limiting incubation step with a 6-fold reduction in the incubation time. Since the same electrode platform is used for both electrochemical signal enhancement and electrochemical sensing, the multifunctional electrode approach provides a highly effective strategy toward fully integrated lab-on-a-chip systems for various biomedical applications. 相似文献