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Recently, organic light‐emitting diodes (OLEDs) employing thermally activated delayed fluorescence (TADF) materials have aroused huge attention in both academia and industry. Compared with fluorescent and phosphorescent materials, TADF materials can theoretically capture 100 % excitons without incorporating noble metals, making them effective emitters and hosts for OLEDs simultaneously. Here, in this review, our recent works on mechanisms and materials of high performance TADF‐sensitized phosphorescent (TSP) OLEDs, TADF‐sensitized fluorescent (TSF) OLEDs and TADF‐sensitized TADF (TST) OLEDs are summarized. Finally, we propose the outlook for the further development and application of TADF‐sensitized OLEDs. 相似文献
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Xiaoli Qin Yifan Dong Minghan Wang Zhiwei Zhu Meixian Li Xiangjian Chen Di Yang Yuanhua Shao 《中国科学:化学(英文版)》2018,61(4):476-482
We report an ultrasensitive protocol for electrochemical sensing using the hydroxyl-rich C-dots assisted synthesis of gold nanoparticles(C-dots@AuNP) as labels with copper depositon reaction. The C-dots catalyzing copper deposition reaction was implemented for the first time. We constructed a sandwich-type immunosensor on the chitosan modified glassy carbon electrode(GCE) by glutaraldehyde(GA) crosslinking, with C-dots@AuNP as biolabels. Copper was deposited on the catalytic surfaces of second antibody-conjugated C-dots@AuNP nanoparticles through CuSO_4-ascorbic acid reduction, because both C-dots and AuNPs could strongly catalyze the CuSO_4 and ascorbic acid to form Cu particles, which amplified the detection signal. Then the corresponding antigen was quantified based on simultaneous chemical-dissolution/cathodic-preconcentration of copper for insitu analysis using anodic stripping square wave voltammetry(ASSWV) directly on the modified electrode. Under optimized conditions, these electrodes were employed for sandwich-type immunoanaly sis, pushing the lower limits of detection(LODs)down to the fg mL~(-1) level for human immunoglobulin G(IgG) and cardiac troponin I(cTnI), a cardiac biomarker. These novel sensors have good stability and acceptable accuracy and reproducibility, suggesting potential applications in clinical diagnostics. 相似文献
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Tomáš Klejch Radek Pohl Zlatko Janeba Minghan Sun Dianne T. Keough Luke W. Guddat Dana Hocková 《Tetrahedron》2018,74(40):5886-5897
Hypoxanthine-guanine-xanthine phosphoribosyltransferase (HGXPRT) is a key enzyme of the purine salvage pathway and its activity is crucial for the survival of certain parasites e.g. Plasmodium falciparum (Pf). Acyclic nucleoside phosphonates (ANPs) containing either guanine or hypoxanthine as the purine base are inhibitors of this enzyme. In this part of a SAR study, these two naturally-occurring nucleobases attached to an acyclic moiety were replaced by allopurinol or favipiravir. Both allopurinol and favipiravir ANPs were prepared via Mitsunobu reaction. The alkylation of favipiravir was optimized to yield both N- and O- regioisomers but the N-regioisomers were unstable under deprotection conditions. Thus, only the ANPs containing the O-isomer of favipiravir and those containing allopurinol were evaluated as potential inhibitors of human HGPRT and PfHGXPRT. Two ANPs with allopurinol as the base have Ki values of 10?μM and 30?μM for PfHGXPRT but do not inhibit human HGPRT activity at concentrations of 100–150?μM. 相似文献
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The production of monovinylacetylene (MVA) through Cu(I)-catalyzed acetylene dimerization reaction was performed in different reaction media. Based on the analyses of crystals precipitated from the catalyst solution and UV-Vis spectra of the catalysts, the reaction mechanism and solvent dependence were studied. The highest yield of MVA can be obtained when dimethylformamide is used as solvent because of its strong coordination ability to Cu(I). The activation of C≡C bond is presumed to be improved when the catalytic metal ion is coordinated by a solvent with less steric hindrance and electron-rich coordination atom. The results of the present study provide a possible way to accelerate the metal-catalyzed homogeneous reaction of alkyne substrates through careful selection of a solvent. 相似文献
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We introduce a class of continuous planar processes, called “semimartingales on rays”, and develop for them a change-of-variable formula involving quite general classes of test functions. Special cases of such processes are diffusions which choose, once at the origin, the rays for their subsequent voyage according to a fixed probability measure in the manner of Walsh (1978). We develop existence and uniqueness results for these “Walsh diffusions”, study their asymptotic behavior, and develop tests for explosions in finite time. We use these results to find an optimal strategy, in a problem of stochastic control with discretionary stopping involving Walsh diffusions. 相似文献
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AbstractA novel π-π* conjugate system photo-catalyst was successfully constructed using aniline, pyrrole and TiO2. The structures of photo-catalyst were measured by XRD, SEM, BET, TEM, FT-IR, XPS and TGA in detail. The photocatalytic properties were investigated in rhodamine B and methyl orange solution, respectively. And the enhance mechanism of π-π* conjugate system was discussed in depth. The weight percentage of Ti weight about 47% in the compound and the π-π* conjugate system did not change the crystal structure of TiO2. The photocatalytic degradation properties of the π-π* conjugate system photo-catalyst could get 99% for rhodamine B and methyl orange after 10 and 15?min, respectively. The introduction of the π-π* conjugate system into TiO2 was beneficial to improve light harvest, photoelectric response and separation of electron-holes. 相似文献
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铜基甲醇催化剂的高温烧结 总被引:3,自引:0,他引:3
对Cu/Zn/Al/Zr甲醇合成催化剂进行高温烧结后采用扫描电镜、透射电镜和X射线衍射等手段对烧结催化剂进行了表征,并对它们的活性和机理模型进行了评价和研究.结果表明,在较高烧结温度下Cu/Zn/Al/Zr甲醇催化剂中的Cu和ZnO晶粒增大,并使催化剂的形貌从串珠状转变为颗粒聚集体;烧结温度越高,晶粒越易增大,因而催化剂活性越低.可采用方程k1/k10=A×t–B描述催化剂失活过程.结果表明,随着烧结温度由400升至500oC,其幂指数B由0.076增至0.171,而失活级数由14降至7.在较低烧结温度下,催化剂微晶在其表面的迁移和聚集是烧结失活的主要因素.随着烧结温度升高,原子通过气相形式迁移的贡献有所增加. 相似文献
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设计和发展简便、高灵敏、高选择性的分析手段以检测低浓度急性心肌梗死生物标志物是目前临床诊断迫切的需求。 电化学发光分析法由于具有稳定性好、灵敏度高、线性范围宽及可控性强等优点,能有效地进行低浓度样品检测。 该方法与生物传感技术相结合,有利于实现生物体液等复杂样品中极低含量急性心肌梗死生物标志物的快速检测。 本文综述了电化学发光生物传感技术在快速检测心肌梗死标志物中近5年的进展,介绍了电化学发光探针和共反应物,以及多组分生物传感检测技术等,并对其在心肌梗死标志物分析中的应用进行了总结。 相似文献
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Customized contact lenses are limited in their correction performance, especially on irregular corneas, owing to decentration and rotation of the lenses. To overcome this limitation, we proposed to customize the back surface of soft contact lenses to match the anterior irregular corneal surface. These lenses were designed to correct anterior corneal aberrations and to improve lens stability. Although in keratoconic eyes the anterior corneal aberrations were effectively corrected, significant residual aberrations were observed. The internal optics, especially the posterior surface of the cornea, was the main source of these residual aberrations. Compared with conventional soft contact lenses, lens stability, on average over three eyes, was improved by a factor of 2 for horizontal and vertical decentrations and a factor of 5 in rotational orientation with the back-surface customized lenses. 相似文献