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Strong Convergence for a Countable Family of Total Quasi-φ-asymptotically Nonexpansive Nonself Mappings in Banach Space 被引量:1
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作者 WANG XIONG-RUI QUAN JING Ji You-qing 《Communications in Mathematical Research》 CSCD 2015年第1期31-39,共9页
The purpose of this article is to introduce a class of total quasi-Ф- asymptotically nonexpansive nonself mappings. Strong convergence theorems for common fixed points of a countable family of total quasi-Ф-asymptot... The purpose of this article is to introduce a class of total quasi-Ф- asymptotically nonexpansive nonself mappings. Strong convergence theorems for common fixed points of a countable family of total quasi-Ф-asymptotically nonexpan- sive mappings are established in the framework of Banach spaces based on modified Halpern and Mann-type iteration algorithm. The main results presented in this article extend and improve the corresponding results of many authors. 展开更多
关键词 strong convergence total quasi-Ф-asymptoticaily nonexpansive nonself generalized projection
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Strong Convergence Theorems for a Family of Quasi-φ-Asymptotically Nonexpansive Mappings 被引量:4
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作者 King Hui GAO Hai Yun ZHOU 《Journal of Mathematical Research and Exposition》 CSCD 2011年第2期303-314,共12页
The purpose of this article is to propose a modified hybrid projection algorithm and prove a strong convergence theorem for a family of quasi-φ-asymptotically nonexpansive mappings.Its results hold in reflexive,stric... The purpose of this article is to propose a modified hybrid projection algorithm and prove a strong convergence theorem for a family of quasi-φ-asymptotically nonexpansive mappings.Its results hold in reflexive,strictly convex,smooth Banach spaces with the property(K).The results of this paper improve and extend recent some relative results. 展开更多
关键词 quasi-φ-asymptotically nonexpansive mapping hybrid algorithm generalized projection strong convergence theorem
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Fixed Point of a Countable Family of Uniformly Totally Quasi- <i>&Oslash</i>-Asymptotically Nonexpansive Multi-Valued Mappings in Reflexive Banach Spaces with Applications 被引量:1
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作者 Yi Li 《Applied Mathematics》 2013年第9期6-12,共7页
The purpose of this article is to discuss a modified Halpern-type iteration algorithm for a countable family of uniformly totally quasi- ? -asymptotically nonexpansive multi-valued mappings and establish some strong c... The purpose of this article is to discuss a modified Halpern-type iteration algorithm for a countable family of uniformly totally quasi- ? -asymptotically nonexpansive multi-valued mappings and establish some strong convergence theorems under certain conditions. We utilize the theorems to study a modified Halpern-type iterative algorithm for a system of equilibrium problems. The results improve and extend the corresponding results of Chang et al. (Applied Mathematics and Computation, 218, 6489-6497). 展开更多
关键词 MULTI-VALUED Mapping Totally quasi- Ø -asymptotically NONEXPANSIVE Countable FAMILY of UNIFORMLY Totally quasi- Ø -asymptotically NONEXPANSIVE MULTI-VALUED Mappings Firmly Convergence
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分次Quasi-内射模和分次Quasi-投射模
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作者 汤建良 黄留佳 易忠 《广西师范大学学报(自然科学版)》 CAS 2000年第1期42-45,共4页
设G是一个群 ,R是一个G 分次环 研究分次quasi 内射模 ,分次quasi 投射模分别与quasi 内射模和quasi 投射模的关系 特别地 。
关键词 quasi-内射模 分次quasi-投射模 模论
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Quasi-90-day oscillation observed in the MLT region at low latitudes from the Kunming meteor radar and SABER 被引量:5
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作者 Wen Yi XiangHui Xue +2 位作者 JinSong Chen TingDi Chen Na Li 《Earth and Planetary Physics》 CSCD 2019年第2期136-146,共11页
Observations of a quasi-90-day oscillation in the mesosphere and lower thermosphere(MLT) region from April 2011 to December 2014 are presented in this study. There is clear evidence of a quasi-90-day oscillation in te... Observations of a quasi-90-day oscillation in the mesosphere and lower thermosphere(MLT) region from April 2011 to December 2014 are presented in this study. There is clear evidence of a quasi-90-day oscillation in temperatures obtained from the Kunming meteor radar(25.6°N, 103.8°E) and Sounding of the Atmosphere using Broadband Emission Radiometry(SABER), as well as in wind observed by the Kunming meteor radar. The quasi-90-day oscillation appears to be a prominent feature in the temperatures and meridional wind tides and presents quite regular cycles that occur approximately twice per year. The amplitudes and phases of the quasi-90-day oscillation in the SABER temperature show a feature similar to that of upward-propagated diurnal tides, which have a vertical wavelength of ~20 km above 70 km. In the lower atmosphere, a similar 90-day variability is presented in the surface latent heat flux and correlates with the temperature in the MLT region. Similar to the quasi-90-day oscillation in temperature, a 90-day variability of ozone(O3) is also present in the MLT region and is considered to be driven by a similar variability in the upwardly-propagated diurnal tides generated in the lower atmosphere. Moreover, the 90-day variability in the absorption of ultraviolet(UV) radiation by daytime O3 in the MLT region is an in situ source of the quasi-90-day oscillation in the MLT temperature. 展开更多
关键词 quasi-90-day OSCILLATION METEOR radar TEMPERATURES SABER TEMPERATURES TIDES latent heat release SABER ozone
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Quasi-6-day waves in the mesosphere and lower thermosphere region and their possible coupling with the QBO and solar 27-day rotation 被引量:3
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作者 JianYuan Wang Wen Yi +1 位作者 TingDi Chen XiangHui Xue 《Earth and Planetary Physics》 CSCD 2020年第3期285-295,共11页
By using atmospheric wind data in the mesopause and lower thermosphere(MLT)region,features of seasonal variations in the quasi-6-day wave(6DW)at different latitudes are analyzed,and modulation of the 6DW by the diurna... By using atmospheric wind data in the mesopause and lower thermosphere(MLT)region,features of seasonal variations in the quasi-6-day wave(6DW)at different latitudes are analyzed,and modulation of the 6DW by the diurnal tide and solar 27-day period is discussed.The data used in the analysis are extracted from a wind dataset collected by a meteor radar chain from December 2008 to November 2017.The meteor radar chain includes four stations,in Mohe,Beijing,Wuhan,and Sanya.Features of seasonal variations in the 6DW indicate that in summer the 6DW is usually strongest during July and August,followed by stronger variations in January and April.At certain altitudes over Wuhan and Sanya,the 6DW is slightly different in different years and altitudes.In our analysis of seasonal variations in the 6DW,we find that it is generally affected by annual oscillations and semiannual oscillations.The annual oscillations of the 6DW in the mid-low latitudes are modulated by the quasibiennial oscillation in the diurnal tide,resulting in seasonal features that are different from those at other latitudes.In addition,the 6DW amplitude at mid-high latitudes has a significant 27-day solar rotation variation,which was prominent in 2016. 展开更多
关键词 quasi-6-day wave meteor radar winds seasonal variations quasibiennial oscillation TIDES 27-day variation
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Characteristics of the quasi-16-day wave in the mesosphere and lower thermosphere region as revealed by meteor radar,Aura satellite,and MERRA2 reanalysis data from 2008 to 2017 被引量:2
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作者 Yun Gong Zheng Ma +7 位作者 Chun Li XieDong Lv ShaoDong Zhang QiHou Zhou ChunMing Huang KaiMing Huang You Yu GuoZhu Li 《Earth and Planetary Physics》 CSCD 2020年第3期274-284,共11页
This study presents an analysis of the quasi-16-day wave(Q16DW)at three stations in the middle latitudes by using a meteor radar chain in conjunction with Aura Microwave Limb Sounder temperature data and MERRA2(Modern... This study presents an analysis of the quasi-16-day wave(Q16DW)at three stations in the middle latitudes by using a meteor radar chain in conjunction with Aura Microwave Limb Sounder temperature data and MERRA2(Modern-Era Retrospective Analysis for Research and Applications,Version 2)reanalysis data from 2008 to 2017.The radar chain consists of three meteor radar stations located at Mohe(MH,53.5°N,122.3°E),Beijing(BJ,40.3°N,116.2°E),and Wuhan(WH,30.5°N,114.6°E).The Q16DW wave exhibits similar seasonal variation in the neutral wind and temperature,and the Q16DW amplitude is generally strong during winter and weak around summer.The Q16DW at BJ was found to have secondary enhancement around September in the zonal wind,which is rarely reported at similar latitudes.The latitudinal variations of the Q16DW in the neutral wind and temperature are quite different.The Q16DW at BJ is the most prominent in both neutral wind components among the three stations and the Q16DW amplitudes at MH and WH are comparable,whereas the wave amplitude in temperature decreases with decreasing latitude.The quasi-geostrophic refractive index squared at the three stations in the period from 2008 to 2017 was revealed.The results indicate that the Q16DW in the mesosphere and lower thermosphere(MLT)at MH has a limited contribution from the lower atmosphere.Around March and October,the Q16DW in the troposphere at BJ can propagate upward into the MLT region,whereas at WH,the contribution to the Q16DW in the MLT region is largely from the mesosphere. 展开更多
关键词 quasi-16-day waves seasonal variations meteor radar winds Aura MLS temperature generation mechanisms
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Phenylfluorenamine-functionalized poly(N-vinylcarbazole)s as dopant-free polymer hole-transporting materials for inverted quasi-2D perovskite solar cells 被引量:1
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作者 Zhengwu Pan Han Gao +11 位作者 Yingying Yang Qin Zou Darui Peng Pinghui Yang Jiangli Cai Jin Qian Jiewei Li Chengrong Yin Nana Wang Renzhi Li Jianpu Wang Wei Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第6期123-131,I0004,共10页
In order to improve the efficiency and stability of inverted three-dimensional(3D) or quasi-2D perovskite solar cells(PSCs) for future commercialization, exploring high efficient dopant-free polymer holetransporting m... In order to improve the efficiency and stability of inverted three-dimensional(3D) or quasi-2D perovskite solar cells(PSCs) for future commercialization, exploring high efficient dopant-free polymer holetransporting materials(HTMs) is still desired and meaningful. One simple and efficient way to achieve high performance dopant-free HTMs is to synthesize novel non-conjugated side-chain polymers via rational molecular design. In this work, N-(4-methoxyphenyl)-9,9-dimethyl-9H-fluoren-2-amine(FMeNPh) groups are introduced into the poly(N-vinylcarbazole)(PVK) side chains to afford two nonconjugated polymers PVCz-DFMeNPh and PVCz-FMeNPh as dopant-free HTMs in inverted quasi-2D PSCs. Benefited from the flexible properties of polyethylene backbone and excellent optoelectronic natures of FMeNPh side-chain groups, PVCz-DFMeNPh with more FMeNPh units exhibited excellent thermal stability, well-matched energy levels and improved charge mobility as compared to PTAA and PVCzFMeNPh. Moreover, the morphologies investigation of quasi-2D perovskite on PVCz-DFMeNPh shows more compact and homogeneous perovskite films than those on PTAA and PVCz-FMeNPh. As a result,the dopant-free PVCz-DFMeNPh based inverted quasi-2D PSCs deliver power conversion efficiency(PCE) up to 18.44% as well as negligible hysteresis and favorable long-term stability, which represents as excellent performance reported to date for inverted quasi-2D PSCs. The results demonstrate the great potentials of constructing non-conjugated side-chain polymer HTMs based on phenylfluorenamine-func tionalized PVK for the development of high efficient and stable inverted 3D or quasi-2D PSCs. 展开更多
关键词 Phenylfluorenamine Non-conjugated polymers Dopant-free Hole-transporting materials quasi-2D perovskite solar cells
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Quasi-α-斜线性Armendariz模
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作者 章东青 殷晓斌 《南通大学学报(自然科学版)》 CAS 2016年第4期80-86,共7页
作为线性Armendariz模和α-斜Armendariz模的推广,引入了quasi-α-斜线性Armendariz模的概念.研究了quasi-α-斜线性Armendariz模的若干性质,讨论了quasi-α-斜线性Armendariz模与其他模之间的关系,并给出了quasi-α-斜线性Armendariz... 作为线性Armendariz模和α-斜Armendariz模的推广,引入了quasi-α-斜线性Armendariz模的概念.研究了quasi-α-斜线性Armendariz模的若干性质,讨论了quasi-α-斜线性Armendariz模与其他模之间的关系,并给出了quasi-α-斜线性Armendariz模的平凡扩张. 展开更多
关键词 Armendariz模 α-斜Armendariz模 线性Armendariz模 quasi-α-斜线性Armendariz模 quasi-线性Armendariz模
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Quasi-3D Numerical Simulation of Tidal Hydrodynamic Field 被引量:1
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作者 宋志尧 薛鸿超 +2 位作者 严以新 茅丽华 徐福敏 《China Ocean Engineering》 SCIE EI 1999年第3期265-276,共12页
Based on the 2D horizontal plane numerical model, a quasi-3D numerical model is established for coastal regions of shallow water. The characteristics of this model are that the velocity profiles;can be obtained at the... Based on the 2D horizontal plane numerical model, a quasi-3D numerical model is established for coastal regions of shallow water. The characteristics of this model are that the velocity profiles;can be obtained at the same time when the equations of the value of difference between the horizontal current velocity and its depth-averaged velocity in the vertical direction are solved and the results obtained are consistent with the results of the 2D, model. The circulating flow in the rectangular area induced by wind is simulated and applied to the tidal flow field of the radial sandbanks in the South Yellow Sea. The computational results from this quasi-3D model are in good agreement with analytical results and observed data. The solution of the finite difference equations has been found to be stable, and the model is simple, effective and practical. 展开更多
关键词 tidal hydrodynamic field quasi-3D numerical model 2D numerical model velocity profile numerical simulation
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Quasi-40-Day Oscillation and Its Teleconnection Structure together with the Possible Dependence on Conversion of Barotropic Unstable Energy of Temporal Mean Flow 被引量:1
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作者 徐建军 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1993年第2期193-200,共8页
A study is made of the distribution of the diagnostic quantity vector E and the teleconnection structure of 30-50 (quasi-40) day oscillation, together with the dependence on the conversion of barotropic unstable energ... A study is made of the distribution of the diagnostic quantity vector E and the teleconnection structure of 30-50 (quasi-40) day oscillation, together with the dependence on the conversion of barotropic unstable energy of mean flow in terms of ECWMF daily 500 hPa grid data in winter, indicating that the energy transportation is closely associated with the westerly jet position, with zonal (meridional) propagation in the strong (weak) wind region, that considerable conversion of barotropic energy occurs at the jet exit region where low-frequency oscillation gains energy from the mean flow, leading to maximum kinetic energy for the oscillation observed there, which is marked by evident barotropy in striking contrast to the baroclinicity at low latitudes and that the teleconnection core is related to the center of action in the atmosphere and bound up with the pattern of the west wind. 展开更多
关键词 quasi-40-Day Oscillation and Its Teleconnection Structure together with the Possible Dependence on Conversion of Barotropic Unstable Energy of Temporal Mean Flow
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Polarization sensitive photodetector based on quasi-1D ZrSe_(3)
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作者 Xingang Wang Tao Xiong +5 位作者 Kaiyao Xin Juehan Yang Yueyang Liu Zeping Zhao Jianguo Liu and Zhongming Wei 《Journal of Semiconductors》 EI CAS CSCD 2022年第10期39-49,共11页
The in-plane anisotropy of transition metal trichalcogenides(MX_(3))has a significant impact on the molding of materi-als and MX_(3) is a perfect choice for polarized photodetectors.In this study,the crystal structure... The in-plane anisotropy of transition metal trichalcogenides(MX_(3))has a significant impact on the molding of materi-als and MX_(3) is a perfect choice for polarized photodetectors.In this study,the crystal structure,optical and optoelectronic aniso-tropy of one kind of quasi-one-dimensional(1D)semiconductors,ZrSe_(3),are systematically investigated through experiments and theoretical studies.The ZrSe_(3)-based photodetector shows impressive wide spectral response from ultraviolet(UV)to near in-frared(NIR)and exhibits great optoelectrical properties with photoresponsivity of 11.9 mA·W^(-1) and detectivity of~106 at 532 nm.Moreover,the dichroic ratio of ZrSe_(3)-based polarized photodetector is around 1.1 at 808 nm.This study suggests that ZrSe_(3) has potential in optoelectronic applications and polarization detectors. 展开更多
关键词 quasi-1D ZrSe_(3) polarization-sensitive
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THE GENERALIZED HYPERSTABILITY OF GENERAL LINEAR EQUATION IN QUASI-2-BANACH SPACE
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作者 Ravinder Kumar SHARMA Sumit CHANDOK 《Acta Mathematica Scientia》 SCIE CSCD 2022年第4期1357-1372,共16页
In this paper,we study the hyperstability for the general linear equation f(ax+by)=Af(x)+Bf(y)in the setting of complete quasi-2-Banach spaces.We first extend the main fixed point result of Brzdek and Ciepliński(Acta... In this paper,we study the hyperstability for the general linear equation f(ax+by)=Af(x)+Bf(y)in the setting of complete quasi-2-Banach spaces.We first extend the main fixed point result of Brzdek and Ciepliński(Acta Mathematica Scientia,2018,38 B(2):377-390)to quasi-2-Banach spaces by defining an equivalent quasi-2-Banach space.Then we use this result to generalize the main results on the hyperstability for the general linear equation in quasi-2-Banach spaces.Our results improve and generalize many results of literature. 展开更多
关键词 HYPERSTABILITY quasi-2-Banach spaces fixed point general linear equation
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Phenylformamidinium-enabled quasi-2D Ruddlesden-Popper perovskite solar cells with improved stability
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作者 Xingcheng Li Wanpei Hu +8 位作者 Yanbo Shang Xin Yu Xue Wang Weiran Zhou Mingtai Wang Qun Luo Chang-Qi Ma Yalin Lu Shangfeng Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第3期680-688,I0018,共10页
Two-dimensional(2D)/quasi-2D perovskite solar cells(PSCs)incorporating organic spacer cations exhibit appealing ambient stability in comparison with their 3D analogs.Most reported organic spacer cations are based on a... Two-dimensional(2D)/quasi-2D perovskite solar cells(PSCs)incorporating organic spacer cations exhibit appealing ambient stability in comparison with their 3D analogs.Most reported organic spacer cations are based on ammonium,whereas formamidinium(FA^(+))has been seldom applied despite that FA has been extensively used in high-efficiency 3D PSCs.Herein,a novel FA-based organic spacer cation,4-chloro-phenylformamidinium(CPFA^(+)),is applied in quasi-2D Ruddlesden-Popper(RP)PSCs for the first time,and methylammonium chloride(MACl)is employed to promote crystal growth and orientation of perovskite film,resulting in high power conversion efficiency(PCE)with improved stability.Upon incorporating CPFA+organic spacer cation and MACl additive,high-quality quasi-2D CPFA_(2)MA_(n-1)Pb_(n)(I_(0.857)Cl_(0.143))_(3n+1)(n=9)perovskite film forms,exhibiting improved crystal orientation,reduced trap state density,prolonged carrier lifetime and optimized energy level alignment.Consequently,the CPFA_(2)MA_(n-1)Pb_(n)(I_(0.857)Cl_(0.143))_(3n+1)(n=9)quasi-2D RP PSC devices deliver a highest PCE of 14.78%.Moreover,the un-encapsulated CPFA-based quasi-2D RP PSC devices maintain~80%of its original PCE after exceeding 2000 h storage under ambient condition,whereas the 3D MAPb I3counterparts retain only~45%of its original PCE.Thus,the ambient stability of quasi-2D RP PSC devices is improved obviously relative to its 3D MAPb I3counterpart. 展开更多
关键词 Perovskite solar cells Organic spacer Formamidinium RUDDLESDEN-POPPER quasi-2D perovskite
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Low-dimensional phases engineering for improving the emission efficiency and stability of quasi-2D perovskite films
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作者 王月 马壮壮 +3 位作者 李营 张飞 陈旭 史志锋 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第6期594-601,共8页
The two-dimensional(2 D) Ruddlesden–Popper-type perovskites, possessing tunable bandgap, narrow light emission,strong quantum confinement effect, as well as a simple preparation method, are identified as a new genera... The two-dimensional(2 D) Ruddlesden–Popper-type perovskites, possessing tunable bandgap, narrow light emission,strong quantum confinement effect, as well as a simple preparation method, are identified as a new generation of candidate materials for efficient light-emitting diodes. However, the preparation of high-quality quasi-2 D perovskite films is still a challenge currently, such as the severe mixing of phases and a high density of defects within the films, impeding the further promotion of device performance. Here, we prepared the quasi-2 D PEA_(2) MA_(n-1) Pbn Br_(3 n+1) perovskite films by a modified spin-coating method, and the phases with large bandgap were effectively suppressed by the vacuum evaporation treatment. We systematically investigated the optical properties and stability of the optimized films, and the photoluminescence(PL) quantum yield of the treated films was enhanced from 23% to 45%. We also studied the emission mechanisms by temperature-dependent PL spectra. Moreover, the stability of films against moisture, ultraviolet light, and heat was also greatly improved. 展开更多
关键词 quasi-2D perovskite films vacuum evaporation optical properties STABILITY
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A HYBRID FIXED POINT RESULT FOR LIPSCHITZ HOMOMORPHISMS ON QUASI-BANACH ALGEBRAS
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作者 Sh. Rezapour M. Derafshpour 《Analysis in Theory and Applications》 2011年第2期109-116,共8页
We shall generalize the results of [9] about characterization of isomorphisms on quasi-Banach algebras by providing integral type conditions. Also, we shall give some new results in this way and finally, give a result... We shall generalize the results of [9] about characterization of isomorphisms on quasi-Banach algebras by providing integral type conditions. Also, we shall give some new results in this way and finally, give a result about hybrid fixed point of two homomorphisms on quasi-Banach algebras. 展开更多
关键词 HOMOMORPHISM hybrid fixed point integral-type condition p-norm quasi- Banach algebra
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A REMARK ON THE QUASI-HARMONIC SPHERES
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作者 Xu Deliang Zhou ChunqinDeptofAppl.Math.,ShanghaiJiaotongUniv.,Shanghai200030 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第2期164-170,共7页
Several theorems on the finiteness of energy for quasi- harmonic spheres are proved, some counter- examples which state thatthe energy of quasi- harmonic sphere may be infinite are given.The results support some con... Several theorems on the finiteness of energy for quasi- harmonic spheres are proved, some counter- examples which state thatthe energy of quasi- harmonic sphere may be infinite are given.The results support some conditions of a question posed by Lin Fanghua and Wang Changyou. 展开更多
关键词 quasi- harmonic sphere harmonic map quasi- energy regular neighborhood.
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Synaptic Transistor Implemented Using Quasi-2D Molybdenum Oxide
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作者 shang dashan sun young 《Bulletin of the Chinese Academy of Sciences》 2017年第3期177-178,共2页
Recent years has seen increasing interest in building artificial synaptic devices to emulate the computation performed by biological synapses.Biological synapses are functional links between neurons,through which info... Recent years has seen increasing interest in building artificial synaptic devices to emulate the computation performed by biological synapses.Biological synapses are functional links between neurons,through which information is transmitted in the neuron network.The information can be stored and processed simultaneously in the same synapse through tuning synaptic weight,which is defined as the strength of the correlation between 展开更多
关键词 Synaptic Transistor Implemented Using quasi-2D Molybdenum Oxide SIMULATION
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Phase Regulation and Defect Passivation Enabled by Phosphoryl Chloride Molecules for Efficient Quasi‑2D Perovskite Light‑Emitting Diodes 被引量:1
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作者 Mingliang Li Yaping Zhao +10 位作者 Jia Guo Xiangqian Qin Qin Zhang Chengbo Tian Peng Xu Yuqing Li Wanjia Tian Xiaojia Zheng Guichuan Xing Wen‑Hua Zhang Zhanhua Wei 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第8期181-191,共11页
Quasi-2D perovskites have attracted tremendous interest for application as lightemission layers in light-emitting diodes(LEDs).However,the heterogeneous n phase and non-uniform distribution still severely limit the fu... Quasi-2D perovskites have attracted tremendous interest for application as lightemission layers in light-emitting diodes(LEDs).However,the heterogeneous n phase and non-uniform distribution still severely limit the further development of quasi-2D perovskite LEDs(Pero-LEDs).Meanwhile,the increased defect density caused by the reduced dimension and grain size induces non-radiative recombination and further deteriorates the device performance.Here,we found that a series of molecules containing phosphoryl chloride functional groups have noticeable enhancement effects on the device performance of quasi-2D Pero-LEDs.Then,we studied the modification mechanism by focusing on the bis(2-oxo-3-oxazolidinyl)phosphinic chloride(BOPCl).It is concluded that the BOPCl can not only regulate the phase distribution by decreasing the crystallization rate but also remain in the grain boundaries and passivate the defects.As a result,the corresponding quasi-2D Pero-LEDs obtained a maximum external quantum efficiency(EQE_(max))of 20.82%and an average EQE(EQE_(ave))of around 20%on the optimal 50 devices,proving excellent reproducibility.Our work provides a new selection of molecular types for regulating the crystallization and passivating the defects of quasi-2D perovskite films. 展开更多
关键词 quasi-2D perovskite Phosphoryl chloride functional group Crystallization control N phase control PASSIVATION
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Bubble dynamics properties of B-particles in a quasi-2D gas-solid fluidized bed:Computational particle fluid dynamics numerical simulation and post-processed by digital image analysis technique
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作者 Zemin Yuan Zhong Huang +4 位作者 Guotao Qin Guanjia Zhao Suxia Ma Hairui Yang Guangxi Yue 《Particuology》 SCIE EI CAS CSCD 2024年第3期223-238,共16页
Bubble dynamics properties play a crucial and significant role in the design and optimization of gas-solid fluidized beds.In this study,the bubble dynamics properties of four B-particles were investigated in a quasi-t... Bubble dynamics properties play a crucial and significant role in the design and optimization of gas-solid fluidized beds.In this study,the bubble dynamics properties of four B-particles were investigated in a quasi-two-dimensional(quasi-2D)fluidized bed,including bubble equivalent diameter,bubble size distribution,average bubble density,bubble aspect ratio,bubble hold-up,bed expansion ratio,bubble radial position,and bubble velocity.The studies were performed by computational particle fluid dynamics(CPFD)numerical simulation and post-processed with digital image analysis(DIA)technique,at superficial gas velocities ranging from 2u_(mf) to 7u_(mf).The simulated results shown that the CPFD simulation combining with DIA technique post-processing could be used as a reliable method for simulating bubble dynamics properties in quasi-2D gas-solid fluidized beds.However,it seemed not desirable for the simulation of bubble motion near the air distributor at higher superficial gas velocity from the simulated average bubble density distribution.The superficial gas velocity significantly affected the bubble equivalent diameter and evolution,while it had little influence on bubble size distribution and bubble aspect ratio distribution for the same particles.Both time-averaged bubble hold-up and bed expansion ratio increased with the increase of superficial gas velocity.Two core-annular flow structures could be found in the fluidized bed for all cases.The average bubble rising velocity increased with the increasing bubble equivalent diameter.For bubble lateral movement,the smaller bubbles might be more susceptible,and superficial gas velocity had a little influence on the absolute lateral velocity of bubbles.The simulated results presented a valuable and novel approach for studying bubble dynamics properties.The comprehensive understanding of bubble dynamics behaviors in quasi-2D gas-solid fluidized beds would provide support in the design,operation,and optimization of gas-solid fluidized bed reactors. 展开更多
关键词 Bubble dynamics properties CPFD simulation quasi-2D gas-solid fluidized bed Digital image analysis
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