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991.
992.
Development of a molecular imprinting thick film electrochemical sensor for cholesterol detection 总被引:1,自引:0,他引:1
A combined molecular imprinting and thick film electrochemical sensor for cholesterol concentration detection had been developed. The ferro-ferric cyanide coupled redox reaction was used as the means to quantify the cholesterol presented in the test medium. This electrochemical sensor employed a modified gold working electrode, a platinum counter electrode and an Ag/AgCl reference electrode. The alkanethiol was used to form the self-assembled monolayer (SAM) on the gold working electrode. The SAM was then used with the cholesterol as the template forming the molecular imprinting layer. This sensor prototype could detect cholesterol concentrations between 66 and 700 nM and only a 1 μL of the sample volume was required. 相似文献
993.
Ya-Hsiang Tai Shih-Che Huang Wan-Ping Chen Yu-Te Chao Yen-Pang Chou Guo-Feng Peng 《Display Technology, Journal of》2007,3(4):426-433
In this paper, the variation characteristics of low-temperature polycrystalline silicon (LTPS) thin-film transistors (TFTs) are investigated with a statistical approach. A special layout is proposed to investigate the device variation with respect to various devices distances. Two non-Gaussian equations are proposed to fit the device parameter distributions, whose the coefficients of determination (R2) are both near 0.9, reflecting the validity of the model. Two benchmark circuits are used to compare the difference between the proposed model and the conventional Gaussian distribution for the device parameter distribution. The output behaviors of the digital and analog circuits show that the variation in the short range would greatly affect the performance of the analog circuits and would instead be averaged in the digital circuits. 相似文献
994.
K.‐S. Chen W.‐H. Liu Y.‐H. Wang C.‐H. Lai P.‐T. Chou G.‐H. Lee K. Chen H.‐Y. Chen Y. Chi F.‐C. Tung 《Advanced functional materials》2007,17(15):2964-2974
A new type of ruthenium complexes 6 – 8 with tridentate bipyridine–pyrazolate ancillary ligands has been synthesized in an attempt to elongate the π‐conjugated system as well as to increase the optical extinction coefficient, possible dye uptake on TiO2, and photostability. Structural characterization, photophysical studies, and corresponding theoretical approaches have been made to ensure their fundamental basis. As for dye‐sensitized solar cell applications, it was found that 6 – 8 possess a larger dye uptake of 2.4 × 10–7 mol cm–2, 1.5 × 10–7 mol cm–2, and 1.3 × 10–7 mol cm–2, respectively, on TiO2 than that of the commercial N3 dye (1.1 × 10–7 mol cm–2). Compound 8 works as a highly efficient photosensitizer for the dye‐sensitized nanocrystalline TiO2 solar cell, producing a 5.65 % solar‐light‐to‐electricity conversion efficiency (compare with 6.01 % for N3 in this study), a short‐circuit current density of 15.6 mA cm–2, an open‐circuit photovoltage of 0.64 V, and a fill factor of 0.57 under standard AM 1.5 irradiation (100 mW cm–2). These, in combination with its superior thermal and light‐soaking stability, lead to the conclusion that the concomitant tridentate binding properties offered by the bipyridine‐pyrazolate ligand render a more stable complexation, such that extended life spans of DSSCs may be expected. 相似文献
995.
Through in situ reduction of a gold precursor, we have tethered gold nanoparticles (Au NPs) to the side chains of poly{2,7‐(9,9′‐dioctylfluorene)‐co‐4‐diphenylamino‐4′‐bipenylmethylsulfide} (PF‐DBMS) through its ArSCH3 anchor groups. The presence of 1 wt % of the tethered Au NPs led to a reduction in the degree of aggregation of the polymer chains, resulting in a 50 % increase in its quantum yield. The electroluminescence of a 1 wt % Au/PF‐DBMS device was almost four times higher in terms of its maximum brightness and its full‐width‐at‐half‐maximum emission peak was much narrower than that of a pure PF‐DBMS device; the presence of a small amount of Au NPs significantly enhances the electron injection and transport and suppresses the photo‐oxidation of PF‐DBMS. 相似文献
996.
Presented are the effects of a guard trace with the optimal number of grounded vias that gives maximum efficiency for preventing crosstalk in parallel double micro-strip lines in a high-speed printed circuit board layout. Compared to a guard trace with two terminal grounded vias, the near-end crosstalk is reduced from 95 to 30 mV and the far-end crosstalk is reduced from 121 to 56 mV 相似文献
997.
Hsu-Feng Chou Ramaswamy A. Zibar D. Johansson L.A. Bowers J.E. Rodwell M. Coldren L.A. 《Photonics Technology Letters, IEEE》2007,19(12):940-942
We propose and demonstrate a novel coherent receiver with feedback for high-linearity analog photonic links. In the proposed feedback receiver, a local phase modulator tracks the phase change of the signal and reduces the effective swing across the phase demodulator without reducing the transmitted signal. The signal-to-noise-ratio is thus maintained while linearity is improved. Up to 20-dB improvement in spur-free dynamic range (SFDR) is achieved experimentally. At 3.13 mA of average photocurrent per photodiode, the measured SFDR is 124.3 dBmiddotHz2/3, which corresponds to an SFDR of 131.5 dBmiddotHz2/3 when the link is shot-noise-limited 相似文献
998.
Hybrid Taguchi-genetic algorithm for global numerical optimization 总被引:11,自引:0,他引:11
Jinn-Tsong Tsai Tung-Kuan Liu Jyh-Horng Chou 《Evolutionary Computation, IEEE Transactions on》2004,8(4):365-377
In this paper, a hybrid Taguchi-genetic algorithm (HTGA) is proposed to solve global numerical optimization problems with continuous variables. The HTGA combines the traditional genetic algorithm (TGA), which has a powerful global exploration capability, with the Taguchi method, which can exploit the optimum offspring. The Taguchi method is inserted between crossover and mutation operations of a TGA. Then, the systematic reasoning ability of the Taguchi method is incorporated in the crossover operations to select the better genes to achieve crossover, and consequently, enhance the genetic algorithm. Therefore, the HTGA can be more robust, statistically sound, and quickly convergent. The proposed HTGA is effectively applied to solve 15 benchmark problems of global optimization with 30 or 100 dimensions and very large numbers of local minima. The computational experiments show that the proposed HTGA not only can find optimal or close-to-optimal solutions but also can obtain both better and more robust results than the existing algorithm reported recently in the literature. 相似文献
999.
Electrodeless dielectrophoresis for micro total analysis systems 总被引:5,自引:0,他引:5
Several examples where a sample-to-answer, lab-on-a-chip chemical analysis system may benefit from EDEP technology in upstream sample preparation (cell sorting, cell lysing, DNA concentration, and purification) and in a back-end detection platform for hybridization and sensitivity enhancement were presented. The simplicity of the device and the lack of metallic electrodes at the trap, which cause electrochemical reactions involving gas evolution, made possible the investigation of the response of biological objects in a wide range of frequencies, especially the low-frequency regime. Above all, EDEP may be seamlessly integrated with the metallic DEP layout, this increasing the flexibility in custom-tailored chip design. 相似文献
1000.
Tse-Ming Tsai Han-Kuan Yu Hsin-Te Shih Ping-Yao Liao Ren-Dar Yang Chou S.T. 《Computer》2003,36(10):63-71
The recent adoption of XML-based Web services standards has further integrated distributed resources with open Internet protocols at the software service level. Developers are moving beyond simply extending Web resource access and are making a sustained effort to tap into the depth of mutual understanding that can be culled from the Web's diverse content. Ultimately, they will organize this information conceptually and place it in the semantic Web's framework. For end users, the vast increase in available services these initiatives provide can imply either more freedom or more chaos. This flood of options raises the vital issue of how emerging technologies can help to automate the manual operations individual applications require. The smart office task automation framework uses Web services, an ontology, and agent components to create an integrated information-service platform that provides user-centric support for automating intranet office tasks. 相似文献