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991.
Bin Su Yang Wang Bo Feng Yongsheng Yan Enwei Zhu Bo Wang Guangbo Che 《Chinese Journal of Physics (Taipei)》2017,55(2):350-354
Organic ultraviolet photodetectors (OUV-PDs) were fabricated utilizing 2-TNATA as an electron donor with Bphen and TPBi as electron acceptors. A high sensitivity of OUV-PDs to UV light was obtained in the range of 300–420 nm. The optimized OUV-PDs composed of Bphen as the acceptor offered a photocurrent density up to 336 µA/cm2 at ?8 V with 365 nm UV light at a power of 1.2 mW/cm2. The high response is attributed to the excellent electron transport ability of Bphen and the matched energy level between 2-TNATA and Bphen. 相似文献
992.
Lei Wang Ruiquan Liu Cong Lv Junjun Ou Feng Liu Shangzhong Liu Min Wang Jiangchun Zhong 《Tetrahedron: Asymmetry》2013,24(4):173-177
Six optically active α-hydroxyl-β,γ-unsaturated acid esters 1a to 1f were synthesised, and they are significant moieties of the cerebrosides. The chiral intermediate alkynol 4 prepared by catalytic asymmetric addition had 99% ee, and which was converted into the target compounds 1a to 1f with high enantiomeric purity. 相似文献
993.
Chung Liao Feng 《Journal of Electrostatics》2013,71(3):551-553
In the literature there are reports of static charges appearing with physical (i.e., phase and temperature) changes of water. One of the purposes of the present report is to refine the measurement of charge in heated water. The experiments described in this report confirm the reported phenomenon by comparing the different amounts of charge produced when different amounts of water are heated to the same temperature and in the same setup. When charge differential is correlated to water differential, the source of charge is better isolated to the change in water temperature rather than to any other possible source. 相似文献
994.
本文研究了亚硝酸盐(NO_2~-)在纳米金和β-环糊精复合修饰碳糊电极(AuNPs-β-CD/CPE)上的电化学行为。实验结果表明,与裸CPE相比,AuNPs-β-CD/CPE对NO_2~-的电化学氧化有显著的促进作用,其氧化峰电流显著增加。同时用循环伏安法(CV)、计时电流法(CA)测定了NO_2~-在AuNPs-β-CD/CPE上的电极反应动力学参数,用线性扫描伏安法(LSV)法测得NO_2~-氧化峰电流与其浓度在6.0×10-6~8.0×10-3 mol·L-1范围内呈良好的线性关系,检出限(S/N=3)为5.7×10-7 mol·L-1。将该传感器应用于水样的检测,相对标准偏差在0.15%~1.40%之间,回收率达99.3%~104.0%,检测结果符合定量测定要求。 相似文献
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997.
A new monomer, (2,5‐dimethoxy)phenylhydroquinone (DMPH), was prepared in a two‐step synthetic procedure. One aromatic poly(ether ether ketone)s with 2,5‐dimethoxy phenyl side group (DMP‐PEEK) was synthesized via an aromatic nucleophilic substitution reaction with 4,4′‐difluorobenzophenone (DFB). Poly(ether ether ketone)s with 2,5‐dihydroxy phenyl side group (DHP‐PEEK) was obtained via hydrolysis of methoxy group on the DMP‐PEEK. Both of the high molecular weight polymers could be obtained despite the steric effect of the bulky pendant groups. The two polymers have good solubility at room temperature. 相似文献
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Fluorescence imaging in the second near-infrared region(900-1700 nm, NIR-II) with a high resolution and penetration depth due to the significantly reduced tissue scattering and autofluorescence has emerged as a useful tool in biomedical fields. Recently, many efforts have been devoted to the development of fluorophores with an emission band covering the long-wavelength end of NIR-II region(1500-1700 nm) to eliminate the autofluorescence. Alternatively, we believe imaging with a narrow bandwidth could also reduce the autofluorescence. As a proof of concept, NaYF4:Yb,Nd@NaYF4 downconversion nanoparticles(DCNPs) with sharp NIR-II emission were synthesized. The luminescence of DCNPs showed a half-peak width of 49 nm centered at 998 nm, which was perfectly matched with a (1000±25) nm bandpass filter. With this filter, we were able to retain most of the emissions from the nanoparticles, while the autofluorescence was largely reduced. After PEGylation, the DCNPs exhibited great performance for blood vessel and tumor imaging in living mice with significantly reduced autofluorescence and interference signals. This work provided an alternative way for the low-autofluorescence imaging and emphasized the importance of narrow emitting rare-earth doped nanoparticles for NIR-II imaging. 相似文献