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排序方式: 共有90条查询结果,搜索用时 31 毫秒
1.
高斯光束计算平板波导自由传输区远场分布及其修正 总被引:2,自引:2,他引:0
对近轴近似条件下求解亥姆霍兹方程得到的高斯光束显式传播公式做了分析,同时,基于基尔霍夫衍射理论,在菲涅耳近似的条件下给出了相应的高斯光束在远场的传播公式,在此基础上,对近轴近似条件做出了定量分析,给出了这个近似条件引入的误差,提出了一种计算高斯光束远场分布的修正方法,并采用有限差分-光束传播方法(FD-BPM)来检验各种方法的准确性。把这种修正方法应用到平面光集成波导器件,如阵列波导光栅(AWG)、蚀刻衍射光栅(EDG)等器件的设计和模拟中,可以大大降低工作的复杂性,同时可以得到精确的结果。 相似文献
2.
显微镜产品质量光电检测的研究 总被引:1,自引:1,他引:0
显微镜产品质量光电检测的实施是光、机、光电、计算机技术的综合运用。本文是笔者多年来研究成果总结,包括了已研制出的XJ-1型生物显微镜多功能光电质检仪及其改进;对显微镜离焦性能检测的探索,共可实现显微镜产品质量七个考核项目的检测与等级分拣。这些成果给显微镜行业提供了先进的检测工具;同时为发展我国显微镜产品检测技术、提高检测水平起积极的促进作用。 相似文献
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用原子吸收法或极谱法测定了对例慢性肾炎病人(A组)和24例慢性肾衰病人(B组)及40名健康人(对照组,C组)全血中的Fe、Zn、Cu、Mn、Se、Pb和Ga含量。结果表明,A组与C组比较.血中Fe的含量A组明显低于C组(P<0.05),Zn、Mn和Se的含量A组均非常明显低于C组(P<0.01),Pb含量A组非常明显高于C组(P<0.01),Cu和Ca含量两组间均无明显差异(P>0.05);B组与C组比较,Fe含量B组明显低于C组(P<0.06),Se含量则B组明显高于C组(P<0.05);Zn、Mn、Cu、Ga含量B组均非常明显低于C组(P<0.01),而Pb含量则B组非常明显高于C组(P<0.01)。 相似文献
4.
Jianmei Han Zhongyan Huang Jingsheng Miao Yuntao Qiu Ziyang Xie Chuluo Yang 《Chemical science》2022,13(12):3402
Blue thermally activated delayed fluorescence (TADF) emitters that can simultaneously achieve narrowband emission and high efficiency in nondoped organic light-emitting diodes (OLEDs) remain a big challenge. Herein, we successfully design and synthesize two blue TADF emitters by directly incorporating carbazole fragments into an oxygen-bridged triarylboron acceptor. Depending on the linking mode, the two emitters show significantly different photophysical properties. Benefitting from the bulky steric hindrance between the acceptor and terminal pendants, the blue emitter TDBA-Cz exhibited a high photoluminescence quantum yield (PLQY) of 88% in neat films and narrowband emission. The corresponding non-doped blue device exhibited a maximum external quantum efficiency (EQE) of 21.4%, with a full width at half maximum (FWHM) of only 45 nm. This compound is the first blue TADF emitter that can concurrently achieve narrow bandwidth and high electroluminescence (EL) efficiency in nondoped blue TADF-OLEDs.A donor–acceptor TADF emitter showed narrowband high-efficiency blue emission by fine molecular modulation. The corresponding OLEDs exhibited a maximum EQE of 21.4% and a small FWHM of 45 nm, representing the most efficient nondoped blue TADF-OLEDs. 相似文献
5.
On <Emphasis Type="Italic">s</Emphasis>-Elementary Super Frame Wavelets and Their Path-Connectedness
A super wavelet of length n is an n-tuple (ψ 1,ψ 2,…,ψ n ) in the product space \(\prod_{j=1}^{n} L^{2}(\mathbb{R})\), such that the coordinated dilates of all its coordinated translates form an orthonormal basis for \(\prod_{j=1}^{n} L^{2} (\mathbb{R})\). This concept is generalized to the so-called super frame wavelets, super tight frame wavelets and super normalized tight frame wavelets (or super Parseval frame wavelets), namely an n-tuple (η 1,η 2,…,η n ) in \(\prod_{j=1}^{n}L^{2} (\mathbb{R})\) such that the coordinated dilates of all its coordinated translates form a frame, a tight frame, or a normalized tight frame for \(\prod_{j=1}^{n} L^{2}(\mathbb{R})\). In this paper, we study the super frame wavelets and the super tight frame wavelets whose Fourier transforms are defined by set theoretical functions (called s-elementary frame wavelets). An m-tuple of sets (E 1,E 2,…,E m ) is said to be τ-disjoint if the E j ’s are pair-wise disjoint under the 2π-translations. We prove that a τ-disjoint m-tuple (E 1,E 2,…,E m ) of frame sets (i.e., η j defined by \(\widehat{\eta_{j}}=\frac{1}{\sqrt{2\pi}}\chi_{E_{j}}\) is a frame wavelet for L 2(?) for each j) lead to a super frame wavelet (η 1,η 2,…,η m ) for \(\prod_{j=1}^{m} L^{2} (\mathbb{R})\) where \(\widehat{\eta_{j}}=\frac{1}{\sqrt{2\pi}}\chi_{E_{j}}\). In the case of super tight frame wavelets, we prove that (η 1,η 2,…,η m ), defined by \(\widehat{\eta_{j}}=\frac{1}{\sqrt{2\pi}}\chi_{E_{j}}\), is a super tight frame wavelet for ∏1≤j≤m L 2(?) with frame bound k 0 if and only if each η j is a tight frame wavelet for L 2(?) with frame bound k 0 and that (E 1,E 2,…,E m ) is τ-disjoint. Denote the set of all τ-disjoint s-elementary super frame wavelets for ∏1≤j≤m L 2(?) by \(\mathfrak{S}(m)\) and the set of all s-elementary super tight frame wavelets (with the same frame bound k 0) for ∏1≤j≤m L 2(?) by \(\mathfrak{S}^{k_{0}}(m)\). We further prove that \(\mathfrak{S}(m)\) and \(\mathfrak{S}^{k_{0}}(m)\) are both path-connected under the ∏1≤j≤m L 2(?) norm, for any given positive integers m and k 0. 相似文献
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9.
TR4终端高性能探测器系统 总被引:1,自引:0,他引:1
描述了兰州中能重离子加速器TR4终端装备的高性能探测器系统的结构性能.各类探测器都达到了很好的性能指标.Si多叠层望远镜,Z/△Z~50,△E/E~0.3%.IC+PSD+SPD+CsI(T1)对数密度望远镜,Z/△Z~44.5,△x~1.7mm.棉球面反射镜结构开始时间探测器装置,△t~140Ps.重离子飞行时间谱仪,A/△A~86,Z/△Z~48,△E/E~0.78%,△t~286ps.9单元和36单元CsI(T1)轻粒子小角度关联探测器阵列,Si+CsI(T1)轻粒子望远镜也达到了很好的性能指标.简述了小角度关联等实验结果. 相似文献
10.
PVDF-HFP composite polymer electrolyte with excellent electrochemical properties for Li-ion batteries 总被引:2,自引:0,他引:2
Hui Xie Zhiyuan Tang Zhongyan Li Yanbing He Yong Liu Hong Wang 《Journal of Solid State Electrochemistry》2008,12(11):1497-1502
Poly (vinylidene fluoride-co-hexafluoropropylene)-based composite polymer electrolyte (CPE) was prepared by phase inversion
technique. In this work, we first applied a novel surface-modified sub-micro-sized alumina, PC-401, as ceramic filler. Various
electrochemical methods were applied to investigate the electrochemical properties of the polymer electrolytes. We found that
the CPE with 10 wt.% PC-401 has excellent electrochemical properties, including the ionic conductivity as high as 0.89 mS
cm−1 and the Li-ion transference number of 0.46. Polymer Li-ion batteries using LiFePO4 as cathode active material exhibited excellent cycling and high-temperature performances. PC-401 shows a promising applicability
in the preparation of polymer electrolyte with high electrochemical properties. 相似文献