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脱氢枞酸二芳胺化合物的前线轨道能级研究 被引量:2
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作者 高宏 沈明贵 +2 位作者 王先凯 宋湛谦 商士斌 《林产化学与工业》 EI CAS CSCD 北大核心 2015年第5期1-4,共4页
通过紫外-可见吸收光谱法和循环伏安法分别求得脱氢枞酸二芳胺化合物a^g的带边值和起始氧化电位,利用经验公式计算了它们的最高占据分子轨道/最低未占分子轨道(HOMO/LUMO)能级和带隙值,探讨了化合物的带隙值与其荧光性能之间的关系。结... 通过紫外-可见吸收光谱法和循环伏安法分别求得脱氢枞酸二芳胺化合物a^g的带边值和起始氧化电位,利用经验公式计算了它们的最高占据分子轨道/最低未占分子轨道(HOMO/LUMO)能级和带隙值,探讨了化合物的带隙值与其荧光性能之间的关系。结果表明:含有大的共轭体系的萘环、联苯环的化合物以及芳环上有甲基、甲氧基取代的化合物具有较小的带隙值,这些化合物分子较容易被激发,因而具有较好的荧光性能。同时,对带隙值的实验数据与优化数据进行了比较,除了化合物d外两者具有基本一致的变化趋势。 展开更多
关键词 脱氢枞酸二芳胺 循环伏安 前线轨道 带隙值 荧光性能
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Bandgap Reference Design by Means of Multiple Point Curvature Compensation 被引量:6
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作者 姜韬 杨华中 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第4期490-495,共6页
A new method,namely multiple point curvature compensation (MPCC),is proposed for the design of a bandgap reference,and its design principles, theoretical derivation, and one feasible circuitry implementation are pre... A new method,namely multiple point curvature compensation (MPCC),is proposed for the design of a bandgap reference,and its design principles, theoretical derivation, and one feasible circuitry implementation are presented. Being different from traditional techniques, this idea focuses on finding multiple temperatures in the whole range at which the first order derivatives of the output reference voltage equal zero. In this way, the curve of the output reference voltage is flattened and a better effect of curvature compensation is achieved. The circuitry is simulated in ST Microelectronics 0. 18μm CMOS technology, and the simulated result shows that the average temperature coefficient is only 1ppm/℃ in the range from - 40 to 125℃. 展开更多
关键词 bandgap reference curvature compensation sub-threshold circuit
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A 0.6 μm CMOS bandgap voltage reference circuit
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作者 梁帮立 王志功 +5 位作者 田俊 冯军 夏春晓 胡艳 张丽 熊明珍 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期221-224,共4页
On the basis of mutual compensation of mobility and threshold voltage temperature effects, a stable CMOS band-gap voltage reference circuit was designed and fabricated in CSMC-HJ 0.6 μm CMOS technology. Operating fro... On the basis of mutual compensation of mobility and threshold voltage temperature effects, a stable CMOS band-gap voltage reference circuit was designed and fabricated in CSMC-HJ 0.6 μm CMOS technology. Operating from 0 to 85 ℃ under a supply voltage ranging from 4.5 to 5.5 V, the voltage reference circuit offers an output reference voltage ranging from 1.122 to 1.176 V and a voltage variation less than ±3.70%. The chip size including bonding pads is only 0.4 mm×0.4 mm and the power dissipation falls inside the scope of 28.3 to 48.8 mW operating at a supply voltage of 4.5 to 5.5 V. 展开更多
关键词 CMOS mutual compensation mobility and threshold voltage temperature effects
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From electromagnetic bandgap to left-handed metamaterials:modelling and applications 被引量:1
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作者 郝阳 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第1期34-40,共7页
In this paper, numerical modelling of left-handed materials (LHMs) is presented using in-house and commercial software packages. Approaches used include the finite-difference time-domain (FDTD) method, finite elem... In this paper, numerical modelling of left-handed materials (LHMs) is presented using in-house and commercial software packages. Approaches used include the finite-difference time-domain (FDTD) method, finite element method (FEM) and method of moments (MoMs). Numerical simulation includes verification of negative refraction and "perfect lenses" construction, investigation of evanescent wave behaviour in layered LHMs, reversed Shell's Law in electromagnetic band gap (EBG)-like structures and construction of LHMs using modified split ring resonators (SRRs). Numerical results were verified to be in good agreement with theory, At the end of this paper, potential applications of LHMs in microwave engineering are discussed. 展开更多
关键词 Numerical modelling Electromagnetic crystals Bandgap Left-handed materials (LHMs)
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An investigation of numerical aperture of air-core photonic bandgap fiber 被引量:1
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作者 XU Xiao Bin GAO Fu Yu +2 位作者 ZHANG Zhi Hao JIN Jing SONG Ning Fang 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2015年第2期352-356,共5页
Air-core photonic bandgap fiber(PBF)is the perfect choice of the next-generation fiber optical gyroscope(FOG),with excellent temperature,electromagnetism and radiation adaptability.Numerical aperture is an important o... Air-core photonic bandgap fiber(PBF)is the perfect choice of the next-generation fiber optical gyroscope(FOG),with excellent temperature,electromagnetism and radiation adaptability.Numerical aperture is an important optical parameter of PBF for application in FOG.The PBF’s maximum theoretical numerical aperture(NAmax)is calculated and compared with the far-field numerical aperture(NAeff)through experiments.The result indicates that the relationship between NAmax and NAeff has much stronger dependence on wavelength than that of the conventional fiber,and they get close at wavelengths near the middle of the photonic bandgap with the error less than 5%.Furthermore,photonic bandgap fiber optical gyroscope(PBFOG)with no fusion splicing points is proposed,and the optimization method and results of the PBF’s structure parameters for application in PBFOG are given from the aspect of numerical aperture. 展开更多
关键词 fiber optical gyroscope (FOG) photonic bandgap fiber (PBF) numerical aperture
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