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171.
Yuxin Xiao Hailan Wang Zongliang Xie Mingyao Shen Rongjuan Huang Yuchen Miao Guanyu Liu Tao Yu Wei Huang 《Chemical science》2022,13(31):8906
Near-infrared (NIR) light-emitting materials show excellent potential applications in the fields of military technology, bioimaging, optical communication, organic light-emitting diodes (OLEDs), etc. Recently, thermally activated delayed fluorescence (TADF) emitters have made historic developments in the field of OLEDs. These metal-free materials are more attractive because of efficient reverse intersystem crossing processes which result in promising high efficiencies in OLEDs. However, the development of NIR TADF emitters has progressed at a relatively slower pace which could be ascribed to the difficult promotion of external quantum efficiencies. Thus, increasing attention has been paid to NIR TADF emitters. In this review, the recent progress of NIR TADF emitters has been summarized along with their molecular design strategies and photophysical properties, as well as electroluminescence performance data of their OLEDs, respectively.This review presents the recent progress of NIR TADF emitters along with their molecular design strategies and photophysical properties, as well as the electroluminescence performance data of the emitters and their OLEDs. 相似文献
172.
d2,8电子体系共价效应对光谱的影响 总被引:1,自引:0,他引:1
在含过渡金属离子的半磁半导体的光学和磁学性质研究中,由于体系的共价性较强,d轨道不再是纯d轨道,而是混合轨道t2g或eg。相应地,需要引入两个共价因子Nt和Ne。建立在混合轨道上的含有共价因子的能量矩阵称为广义能量矩阵。建立了d2,8电子体系的(45×45)阶广义能量矩阵。在广义能量矩阵中,拉卡(Racah)参量A不再是相加常量,同时,d8电子体系不能简单地视为互补的d2空穴体系,因为它们的能量矩阵形式不同。Nt和Ne虽然是属于两个不同轨道的不同的共价因子,但在数值上不能有大的差别,因为考虑进共价效应后,拉卡静电参量A对能级计算有极大的影响。这意味着在通常的光谱拟合中所采用的BCΔ方案是好的近似。以上结论被应用于ZnS∶Ni2 的d-d跃迁谱,计算结果与实验符合。 相似文献
173.
Broadband Sheet Parametric Oscillator for x~((2)) Optical Frequency Comb Generation via Cavity Phase Matching 下载免费PDF全文
Xin Ni Kunpeng Jia Xiaohan Wang Huaying Liu Jian Guo Shu-Wei Huang Baicheng Yao Nicolò Sernicola Zhenlin Wang Xinjie Lv Gang Zhao Zhenda Xie Shi-Ning Zhu 《中国物理快报》2021,(6):37-49
We demonstrate a broadband optical parametric oscillation, using a sheet cavity, via cavity phase-matching. A21.2 THz broad comb-like spectrum is achieved, with a uniform line spacing of 133.0 GHz, despite a relatively large dispersion of 275.4 fs~2/mm around 1064 nm. With 22.6% high slope efficiency, and 14.9 kW peak power handling, this sheet optical parametric oscillator can be further developed for x~((2)) comb. 相似文献
174.
Yongle Zhao Huichen Xie Wenwen Shi Hong Wang Chenyi Shao Can Li 《Journal of Energy Chemistry》2022,(1):33-37
Tantalum nitride(Ta3N5) is a very promising photoanode material due to its narrow band gap(2.1 eV)and suitable band alignment for solar water splitting.However,it suffers from severe photocorrosion during water oxidation.In this work,it was found that surface passivation by AlOx and TiOx layers results in dramatically different PEC performance of Ta3N5 photoanode for water oxidation.The mechanism study indicates that the negative ... 相似文献
175.
Yang Ye Xiang Qi Bing Xu Ying Lin Huan Xiang Liang Zou Xiang-Yang Ye Tian Xie 《Chemical science》2022,13(23):6959
Herein, we present a facile and efficient allylation method via Ni-catalyzed cross-electrophile coupling of readily available allylic acetates with a variety of substituted alkenyl bromides using zinc as the terminal reductant. This Ni-catalyzed modular approach displays excellent functional group tolerance and a broad substrate scope, which the creation of a series of 1,4-dienes including several structurally complex natural products and pharmaceutical motifs. Moreover, the coupling strategy has the potential to realize enantiomeric control. The practicality of this transformation is demonstrated through the potent modification of the naturally antitumor active molecule β-elemene.Herein, we present a facile and efficient allylation method via Ni-catalyzed cross-electrophile coupling of readily available allylic acetates with a variety of substituted alkenyl bromides using zinc as the terminal reductant. 相似文献
176.
Shuang Liu Xingzhu Chen Mingyue Yu Jianing Li Jinyao Liu Zunxuan Xie Fengxiang Gao Yuyan Liu 《Molecules (Basel, Switzerland)》2022,27(12)
Breakthroughs in the field of nanotechnology, especially in nanochemistry and nanofabrication technologies, have been attracting much attention, and various nanomaterials have recently been developed for biomedical applications. Among these nanomaterials, nanoscale titanium dioxide (nano-TiO2) has been widely valued in stomatology due to the fact of its excellent biocompatibility, antibacterial activity, and photocatalytic activity as well as its potential use for applications such as dental implant surface modification, tissue engineering and regenerative medicine, drug delivery carrier, dental material additives, and oral tumor diagnosis and treatment. However, the biosafety of nano-TiO2 is controversial and has become a key constraint in the development of nano-TiO2 applications in stomatology. Therefore, in this review, we summarize recent research regarding the applications of nano-TiO2 in stomatology, with an emphasis on its performance characteristics in different fields, and evaluations of the biological security of nano-TiO2 applications. In addition, we discuss the challenges, prospects, and future research directions regarding applications of nano-TiO2 in stomatology that are significant and worthy of further exploration. 相似文献
177.
178.
Tingjunhong Ni Zichao Ding Fei Xie Yumeng Hao Junhe Bao Jingxiang Zhang Shichong Yu Yuanying Jiang Dazhi Zhang 《Molecules (Basel, Switzerland)》2022,27(11)
A series of triazole derivatives containing phenylethynyl pyrazole moiety as side chain were designed, synthesized, and most of them exhibited good in vitro antifungal activities. Especially, compounds 5k and 6c showed excellent in vitro activities against C. albicans (MIC = 0.125, 0.0625 μg/mL), C. neoformans (MIC = 0.125, 0.0625 μg/mL), and A. fumigatus (MIC = 8.0, 4.0 μg/mL). Compound 6c also exerted superior activity to compound 5k and fluconazole in inhibiting hyphae growth of C. albicans and inhibiting drug-resistant strains of C. albicans, and it could reduce fungal burdens in mice kidney at a dosage of 1.0 mg/kg. An in vivo efficacy evaluation indicated that 6c could effectively protect mice models from C. albicans infection at doses of 0.5, 1.0, and 2.0 mg/kg. These results suggested that compound 6c deserves further investigation. 相似文献
179.
以醋酸铀酰为主要试剂, 在负离子检测模式下, 采用电喷雾串联质谱法制备了甲基羟基铀酰负离子. 实验发现, 气相中的甲基羟基铀酰离子与水分子发生分子离子复分解反应, 并用串联质谱法对反应产生的离子性产物进行了结构确认, 提出了反应的可能机理. 热力学计算结果表明, 该反应的ΔGReaction为-473.0 kJ/mol, ΔHReaction为-236.5 kJ/mol, ΔSSystem为0.792 kJ·mol-1·K-1. 该反应的速率常数为2.26 s-1. 相似文献
180.
This study addresses the effectiveness of a simple stiffness tailoring concept to delay damage initiation, control damage progression, and improve residual strength in tensile-loaded composite plates with a central circular cutout. The tailoring concept is to simply reposit all axially oriented (0°) material into regions near the edge of the plate away from the cutout. This tailoring is done in a way so as not to affect the weight of the plate. This accomplishes several beneficial changes in the way that the plate resists loading with no increases in material cost or weight. Lowering the axial stiffness of the laminate surrounding the cutout lowers the stress concentration. Increasing the axial stiffness near edges of the plate attracts loading away from the vicinity of the cutout to further lower stresses in the critical cutout region. This study focuses on in-plane response including damage progression and residual strength as a function of the degree of tailoring and cutout size. Strength and stiffness properties typical of IM7/8551-7 preperg material were assumed and a modified version of the Hashin failure criteria was used to identify the local damage. Results show that tailoring can significantly increase the damage initiation load and the residual strength. In some cases, observed evidence shows that tailoring performs as a damage arrest mechanism. 相似文献