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101.
Seokwoo Kang Hayoon Lee Hyocheol Jung Donghee Shin Miyeon Park 《Molecular Crystals and Liquid Crystals》2018,662(1):96-101
ABSTRACTTIACA-I, TIACA-II were synthesized by changing the substitution position of the imidazole group in the diazocine core. TIACA-I, TIACA-II in the film state showed absorption in the range of 354 to 392 nm and exhibited blue photoluminescence (PL) emissions at 448 and 462 nm, respectively. The PL wavelength of TIACA-II is red-shifted by 14 nm than that of TIACA-I due to the electron-donating intensity depending on the position of the imidazole group. The use of TIACA-II in a non-doped OLED device resulted in blue emission with current efficiency of 2.84 cd/A and CIE of (0.15, 0.18). 相似文献
102.
A blue phase liquid crystal (BPLC) lens with multifunction using multi-electrode structure and a dielectric layer with high dielectric constant is proposed. The refractive index of the BPLC can be changed flexibly in different regions. Some functional or technical requirements such as switch between positive and negative lenses can be achieved. The lens reveals a good parabolic refractive index distribution and focus adjustment capacity simultaneously. The applied voltage on the electrodes is regular and computable. To decrease the applied voltage of the proposed lens with a large diameter, a drive-type adopted Fresnel lens is introduced. 相似文献
103.
S. S. Nath D. Chakdar G. Gope A. Talukdar D. K. Avasthi 《Journal of Dispersion Science and Technology》2013,34(7):1111-1113
We report synthesis of ZnS quantum dots by chemical method at room temperature. In this technique, ZnS quantum dots are produced by simple chemical reactions where zeolite, acts as matrix, plays the key role in controlling particle growth during synthesis. Quantum dots exhibit luminescence properties such as Zn2+ related emission, efficient low voltage electroluminescence, and super linear voltage-brightness EL characteristics. This study demonstrates the technological importance of semiconductor nanosystems prepared by low cost chemical route. 相似文献
104.
105.
溶胶-凝胶法固定胆固醇氧化酶偶联普鲁士蓝化学修饰电极的研究 总被引:9,自引:0,他引:9
用溶胶-凝胶法将胆固醇氧化酶固定在普鲁士蓝修饰的玻碳电极表面,制成了一种新型胆固醇传感器,实现了低电位下对胆固醇的间接测定,胆固醇的测定范围伏安法为5×10-7~8×10-5mol/L,安培法为5×10-6~5×10-4mol/L.伏安法检出限为1.2×10-7mol/L,是目前所见灵敏度最高的胆固醇传感器之一,该传感器对胆固醇的测定可避免常规电化学传感器测定中由于样品中大量存在的易氧化物质所带来的干扰,该传感器的寿命长,使用次数在300次以上. 相似文献
106.
107.
普鲁士蓝修饰电极结合硅溶胶-凝胶技术制备高灵敏葡萄糖传感器 总被引:9,自引:0,他引:9
基于普鲁士蓝修饰玻碳电极结合二氧化硅溶胶 凝胶固定化酶技术构造具有“三明治”式结构的酶电极。考察了酶电极对葡萄糖的电化学响应以及操作条件。结果表明 :所制备的传感器在pH 6 .5 ,电位为- 0 .0 5V条件下对葡萄糖在 0~ 5mmol/L呈线性响应 ,响应时间为 12s ,检出限为 0 .0 2mmol/L ,灵敏度高达1 182 μA/ (mmol·L-1)。传感器的稳定性好 ,4 5d其响应值仍保持 90 %。 相似文献
108.
W. Russ Algar 《Analytica chimica acta》2010,673(1):1-25
A comprehensive review of the development of assays, bioprobes, and biosensors using quantum dots (QDs) as integrated components is presented. In contrast to a QD that is selectively introduced as a label, an integrated QD is one that is present in a system throughout a bioanalysis, and simultaneously has a role in transduction and as a scaffold for biorecognition. Through a diverse array of coatings and bioconjugation strategies, it is possible to use QDs as a scaffold for biorecognition events. The modulation of QD luminescence provides the opportunity for the transduction of these events via fluorescence resonance energy transfer (FRET), bioluminescence resonance energy transfer (BRET), charge transfer quenching, and electrochemiluminescence (ECL). An overview of the basic concepts and principles underlying the use of QDs with each of these transduction methods is provided, along with many examples of their application in biological sensing. The latter include: the detection of small molecules using enzyme-linked methods, or using aptamers as affinity probes; the detection of proteins via immunoassays or aptamers; nucleic acid hybridization assays; and assays for protease or nuclease activity. Strategies for multiplexed detection are highlighted among these examples. Although the majority of developments to date have been in vitro, QD-based methods for ex vivo biological sensing are emerging. Some special attention is given to the development of solid-phase assays, which offer certain advantages over their solution-phase counterparts. 相似文献
109.
110.
The double-layer penetration electrode structure is proposed to obtain the low-operating voltage blue-phase liquid crystal display (BPLCD) with single electro-optic curve for red-green-blue (RGB) colours in every pixel, which is more suitable for the field-sequential-colour display. The different influences of electrode’s parameters and driving methods on the electro-optical properties of the proposed BPLCD are investigated. The results demonstrate that the operating voltage can be reduced from 53.80 V to 23.00 V for red colour. Besides, the coincident voltage-dependent transmittance curves for RGB colours are obtained by adjusting the applied voltage of sub-electrode. Thus, RGB lights can pass through every pixel with single electro-optic curve, which is good for resolution enhancement and single gamma driving. Besides, the maximum gamma shift of the proposed BPLCD is less than 0.1099 at 60° polar angle for the red colour, and the gamma shift difference between red and blue colours is only 0.0542. If the high dielectric constant material is used as the protrusion, the operating voltage can be further decreased, which is close to that of the BPLCD with wall-shaped electrode structure. 相似文献