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81.
Yi Yang Yi Qiu Dr. Pifu Gong Dr. Lei Kang Gaomin Song Xiaomeng Liu Prof. Junliang Sun Prof. Zheshuai Lin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(22):5648-5651
The first alkaline-earth metal tin(II) phosphate, BaSn2(PO4)2, has been discovered, which consists of layered structures constructed from strictly alternating [SnO3]4− and [PO4]3− moieties. This compound is expected to have a large birefringence with Δn≈0.071 at 1064 nm, owing to the presence of stereochemically active lone pair metal cations. 相似文献
82.
Meng-Meng Zhao Lin Zhou Ping-Ping Shi Xuan Zheng Xiao-Gang Chen Ji-Xing Gao Lei He Prof. Dr. Qiong Ye Prof. Dr. Cai-Ming Liu Prof. Dr. Da-Wei Fu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(25):6447-6454
Organic–inorganic hybrid perovskite-type multiferroics have attracted considerable research interest owing to their fundamental scientific significance and promising technological applications in sensors and multiple-state memories. The recent achievements with divalent metal dicyanamide compounds revealed such malleable frameworks as a unique platform for developing novel functional materials. Herein, two 3D organic–inorganic hybrid perovskites [Et3P(CH2)2F][Mn(dca)3] ( 1 ) and [Et3P(CH2)2Cl][Mn(dca)3] ( 2 ) (dca=dicyanamide, N(CN)2−) are presented. Accompanying the sequential phase transitions, they display a broad range of intriguing physical properties, including above room temperature ferroelastic behavior, switchable dielectricity, and low-temperature antiferromagnetic ordering (Tc=2.4 K for both 1 and 2 ). It is also worth noting that the spontaneous strain value of 1 is far beyond that of 2 in the first ferroelastic phase, as a result of the precise halogen substitution. From the point view of molecular design, this work should inspire further exploration of multifunctional molecular materials with desirable properties. 相似文献
83.
Liu Jun-Wei Shen Shu-Qian Li Ming Li Lei 《International Journal of Theoretical Physics》2021,60(5):1712-1719
International Journal of Theoretical Physics - Quantum coherence, coming from quantum superposition, occupies a significant position in the field of physics. We put forward a lower bound of the... 相似文献
84.
Two new Zn2Dy2 complexes were constructed from Zn (II) salen‐type Schiff base complex fragment and 2,6‐pyridinedimethanol (H2pdm) or its Br‐substituted analogue (4‐bromopyridine‐2,6‐diyl)dimethanol (H2Brpdm); their molecular formulas are [Zn2Dy2(L)2(pdm)2(MeOH)2](ClO4)2 [ 1 , H2L = N, N′‐ bis(3‐methoxysalicylidene)‐1,3‐diaminopropane] and [Zn2Dy2(L)2(Brpdm)2(MeOH)2](ClO4)2 [ 2 ], the Dy (III) ions of which have a NO7 triangular dodecahedral coordination sphere. The two complexes show not only ferromagnetic interaction but also field‐induced single‐molecule magnet (SMM) behavior, which are rare Dy (III)‐containing cluster complexes with the NO7 triangular dodecahedral coordination sphere that can show good magnetic relaxation. The energy barrier value of complex 2 is higher than those of complex 1 and the Dy (III) complexes with the DyNO7 triangular dodecahedral coordination configuration reported in the literature. 相似文献
85.
Mengjie Hu Haiquan Chen Mengxia Wang Gang Liu Chunhai Chen Guangtao Qian Youhai Yu 《Journal of polymer science. Part A, Polymer chemistry》2021,59(4):329-339
Polyimides (PI's) with low-dielectric constant and excellent organic solubility have broad application prospects in the electronic field. Herein, this study designed a series of novel, low dielectric, organic soluble PI films by creatively introducing fluorene and pyridine ring into diamine monomers. Because of the noncoplanar structure of fluorenyl and the polarization of pyridine ring, PI films achieved a low-dielectric constant (2.22–3.09 at 10 MHz) and excellent organic solubility. Even in some organic solvents with low-boiling points, these PI films still exhibited outstanding solubility. In addition, all the films possessed high-tensile strength (≈120 MPa) and excellent optical transparency (>70%, 450 nm). It was worth noting that the glass transition temperature of films was all above 280°C and 5% weight loss temperature (T5%) was at 486–553°C. In general, the novel high-performance low-dielectric PI films are expected to be used in the field of microelectronics. 相似文献
86.
87.
Wei Yuting Wang Qihua Liu Wei 《Annals of the Institute of Statistical Mathematics》2021,73(3):535-553
Annals of the Institute of Statistical Mathematics - In this paper, a model averaging approach is developed for the linear regression models with response missing at random. It is shown that the... 相似文献
88.
Periodica Mathematica Hungarica - Subsets with “good” properties in finite fields are widely applied in coding and cryptography. In this paper we introduce pseudorandom measures for... 相似文献
89.
A novel tiled Ti:sapphire(Ti:S)amplifier was experimentally demonstrated with>1 J amplified chirped pulse output.Two Ti:S crystals having dimensions of 14 mm×14 mm×25 mm were tiled as the gain medium in a four-pass amplifier.Maximum output energy of 1.18 J was obtained with 2.75 J pump energy.The energy conversion efficiency of the tiled Ti:S amplifier was comparable with a single Ti:S amplifier.The laser pulse having the maximum peak power of 28 TW was obtained after the compressor.Moreover,the influence of the beam gap on the far field was discussed.This novel tiled Ti:S amplifier technique can provide a potential way for 100 PW or EW lasers in the future. 相似文献
90.
Yunliang Liu Peiji Deng Ruqiang Wu Ramadan A. Geioushy Yaxi Li Yixian Liu Fengling Zhou Haitao Li Chenghua Sun 《Frontiers of Physics》2021,16(5):53503
The large-scale production of ammonia mainly depends on the Haber–Bosch process, which will lead to the problems of high energy consumption and carbon dioxide emission. Electrochemical nitrogen fixation is considered to be an environmental friendly and sustainable process, but its efficiency largely depends on the activity and stability of the catalyst. Therefore, it is imperative to develop highefficient electrocatalysts in the field of nitrogen reduction reaction (NRR). In this paper, we developed a BiVO4/TiO2 nanotube (BiVO4/TNT) heterojunction composite with rich oxygen vacancies as an electrocatalytic NRR catalyst. The heterojunction interface and oxygen vacancy of BiVO4/TNT can be the active site of N2 dynamic activation and proton transition. The synergistic effect of TiO2 and BiVO4 shortens the proton transport path and reduces the over potential of chemical reaction. BiVO4/TNT has high ammonia yield of 8.54 μg·h−1·cm−2 and high Faraday efficiency of 7.70% in −0.8 V vs. RHE in 0.1 M Na2SO4 solution. 相似文献