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排序方式: 共有338条查询结果,搜索用时 140 毫秒
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Kenkera Rayappa Naveen Dr. Keshavananda Prabhu CP Dr. Ramanaskanda Braveenth Prof. Jang Hyuk Kwon 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(12):e202103532
Pure organic molecules based thermally activated delayed fluorescence (TADF) emitters have been successfully developed in recent years for their propitious application in highly efficient organic light emitting diodes (OLEDs). In the case of orange red emitters, the non-radiative process is known to be a serious issue due to its lower lying singlet energy level. However, recent studies indicate that there are tremendous efforts put to develop efficient orange red TADF emitters. In addition, the external quantum efficiency (EQE) of heteroaromatic based orange red TADF OLEDs surpassed 30 %. Such heteroaromatic type emitters showed wide emission spectra; therefore, more attention is being paid to develop highly efficient orange red TADF emitters along with good color purity. Herein, the recent progress of orange red TADF emitters based on molecular structures, such as cyanobenzene, heteroaromatic, naphthalimide, and boron-based acceptors, are reviewed. Further, our insight on these acceptors has been provided by their photophysical studies and device performances. Future perspectives of orange red TADF emitters for real practical applications are discussed. 相似文献
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Elution profiles of lanthanides with α‐hydroxyisobutyric acid by ion exchange chromatography using fine resin 下载免费PDF全文
Rahul Trikha Bal Krishan Sharma Kanwal Nain Sabharwal Krishan Prabhu 《Journal of separation science》2015,38(21):3810-3814
Experiments were carried out using a strong acid cation exchange resin with a particle size of 75–150 μm, termed as “fine resin” in hydrogen ion form for the elution of individual lanthanides Sm, Eu, Gd, Tb, and Dy that are produced as fission products in the spent nuclear fuel and generated in the effluent during reprocessing of spent nuclear fuel. Batch experiments were carried out to study the effect of concentration of nitric acid on distribution coefficient. The distribution coefficient values for these individual lanthanides were determined in nitric acid medium in the concentration range of 0.01–4.0 N. Uptake of each individual lanthanide by resin was increased with increased nitric acid concentration from 0.01 to 0.5 N and remained similar from 0.5 to 1.0 N and decreased thereafter up to 4.0 N. Column experiments were also carried out using the same resin to study the parameters like pH of the eluent, flow rate, and resin bed height under isocratic elution conditions for eluting lanthanide elements using α‐hydroxyisobutyric acid as eluent. The results of this study have indicated the possibility for the elution of individual lanthanides. 相似文献
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Pradeepa Prabakaran Ramesh Prabhu Manimuthu Sowmya Gurusamy 《Journal of Solid State Electrochemistry》2017,21(5):1273-1285
Organic-inorganic hybrid membranes based on poly(ethylene oxide) (PEO) 6.25 wt%/poly(vinylidene fluoride hexa fluoro propylene) [P(VdF-HFP)] 18.75 wt% were prepared by using various concentration of nanosized barium titanate (BaTiO3) filler. Structural characterizations were made by X-ray diffraction and Fourier transform infrared spectroscopy, which indicate the inclusion of BaTiO3 in to the polymer matrix. Addition of filler creates an effective route of polymer-filler interface and promotes the ionic conductivity of the membranes. From the ionic conductivity results, 6 wt% of BaTiO3-incorporated composite polymer electrolyte (CPE) showed the highest ionic conductivity (6 × 10?3 Scm?1 at room temperature). It is found that the filler content above 6 wt% rendered the membranes less conducting. Morphological images reveal that the ceramic filler was embedded over the membrane. Thermogravimetric and differential thermal analysis (TG-DTA) of the CPE sample with 6 wt% of the BaTiO3 shows high thermal stability. Electrochemical performance of the composite polymer electrolyte was studied in LiFePO4/CPE/Li coin cell. Charge-discharge cycle has been performed for the film exhibiting higher conductivity. These properties of the nanocomposite electrolyte are suitable for Li-batteries. 相似文献
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Neha Prabhu 《Czechoslovak Mathematical Journal》2017,67(2):439-455
A classical result in number theory is Dirichlet’s theorem on the density of primes in an arithmetic progression. We prove a similar result for numbers with exactly k prime factors for k > 1. Building upon a proof by E.M. Wright in 1954, we compute the natural density of such numbers where each prime satisfies a congruence condition. As an application, we obtain the density of squarefree n ≤ x with k prime factors such that a fixed quadratic equation has exactly 2 k solutions modulo n. 相似文献
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Abstract: Reaction of a number of alkyl halides with tetrathiomolybdate in water as the solvent affords the corresponding disulfides in good yields. 相似文献
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