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Jackson’s theorem in Q_p spaces

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science{1. mathematics 2010年第2期53卷 367-372页

作者： CHEN YingWei 1.& ren {1. 1. 2, 1.department of mathematics, University of science and technology of china, hefei 230026, china 2 department of mathematics, University of Aveiro, P-381.-1.3 Aveiro, Portugal 1. department of {1. University of Science and Technology of China Hefei 230026 China2. Department of Mathematics University of Aveiro P-3810-193 Aveiro Portugal

A Jackson type inequality in Q p spaces is established, i.e., for any f (z) = Σ∞ j=0 ajzj ∈ Qp , 0≤p 1. and k-1.∈ N,where ω(1.k, f, Q p ) is the modulus of continuity in Q p spaces and C(a) is an absolute const... 详细信息

关键词： Q p space BMOA polynomial approximation

Almansi decomposition for Dunkl operators

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science{1. mathematics 2005年第z1期48卷 333-342页

作者： ren {1. department of {1. University of Science and Technology of ChinaHefei230026China

Let Ω be a G-invariant convex domain in RN including 0, where G is a Coxeter group associated with reduced root system R. We consider functions f defined in Ω which are Dunkl polyharmonic, i.e. (△h)nf =0 for some integer n. Here △h=∑j=1. Dj2 is the Dunkl Laplacian, and Dj is the Dunkl operator attached to the Coxeter group G, where kv is a multiplicity function on R and σv is the reflection with respect to the root v. We prove that any Dunkl polyharmonic function f has a decomposition of the form f(x)=f0(x)+|x|2f1.x)+…+|x|2(n-1.fn-1.x),(?)x∈Ω, where fj are Dunkl harmonic functions, i.e. △hfj = 0. This generalizes the classical Almansi theorem for polyharmonic functions as well as the Fischer decomposition.

关键词： Dunkl operators, Almansi decomposition, Dunkl polyharmonic.

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等离子体扩散流中金属平板上下游的鞘层结构

核聚变与等离子体物理 2012年第1期32卷 21-26页

作者：郑尧邦马锦秀李毅人李卫中国科学技术大学近代物理系中国科学院基础等离子体物理重点实验室和磁约束等离子体理论中心合肥230026 中国空气动力研究与发展中心绵阳621000

利用发射探针诊断了处于扩散等离子体流场中平板两侧的鞘层电势分布并给出鞘层厚度及边界电场。结合Child-Langmuir(CL)定律并利用一维流体模型,分析对比了鞘厚及边界电场。结果显示,上下游的鞘层呈现不对称结构,下游比上游厚,边界电场... 详细信息

利用发射探针诊断了处于扩散等离子体流场中平板两侧的鞘层电势分布并给出鞘层厚度及边界电场。结合Child-Langmuir(CL)定律并利用一维流体模型,分析对比了鞘厚及边界电场。结果显示,上下游的鞘层呈现不对称结构,下游比上游厚,边界电场下游比上游弱,并且下游的预鞘还呈现类似虚阳极的结构。上下游CL鞘的厚度满足线性比例关系,比例系数约为1.2,且实验值与理论值非常接近。上下游CL鞘的边界电场与模型Te/(eλD)比较接近,上游Bohm鞘边界电场的实验结果与过渡区模型e/(3D/5i2/5)T e较符合,但下游Bohm鞘的边界电场与现有模型有较大差异。

关键词：等离子体鞘层上下游边界电场

Initiating,growing and cracking of hydrogen blisters

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science Bulletin 2005年第17期 148-151页

作者： ren Xuechong1. SHAN {1.1. CHU Wuyang1. SU Yanjing1. GAO Kewei1. QIAO Lijie1. JIANG Bo2, CHEN Gang2 & CUI Yinhui2 1. department of Materials Physics, University of science and Technol-ogy Beijing, Beijing 1.0083, china 2. technology Center of Ma’anshan Steel & Iron Corporation, Ma’anshan 432000, china

The growing process of a hydrogen blister in a wheel steel was observed in situ with an optical microscope, and the fracture surfaces formed from broken blisters on a wheel steel and bulk metallic glass were investigated. The initiating, growing, cracking and breaking of hydrogen blis-ters are as follows. Supersaturated vacancies can increase greatly during charging and gather together into a vacancy cluster (small cavity). Hydrogen atoms become hydrogen molecules in the vacancy cluster and hydrogen molecules can stabilize the vacancy cluster. The small cavity becomes the nucleus of hydrogen blister. The blister will grow with enter-ing of vacancies and hydrogen atoms. With increasing hy-drogen pressure, plastic deformation occurs first, the hydro-gen blister near the surface extrudes, and then cracks initiate along the wall of the blister with further increasing hydrogen pressure. A cracked blister can grow further through propa-gating of cracks until it breaks.

关键词： hydrogen blister initiating growing cracking breaking.

Coefficient multipliers of mixed norm space in the ball Dedicated to Professor Sheng GONG on the occasion of his 75th birthday

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science{1. mathematics 2006年第11期49卷 1491-1503页

作者： SHI Jihuai ren {1. department of {1. University of Science and Technology of China Hefei 230026 China Department of Mathematics University of Science and Technology of China Hefei 230026 China

In the paper, we characterize the coefficient multiplier spaces of mixed norm spaces (Hp,q((?)1.,Hu,v((?)2)) for the values of p, q, u, v in three cases: (i)01.v)≤frr. (ii) v =∞,01.u, q≤∞. (iii) 1.v≤2≤q≤∞, and 01.p, u≤∞. The first case extends the result of Blasco, Jevtic, and Pavlovic in one variable. The third case generalizes partly the results of Jevtic, Jovanovic, and Wojtaszczyk to higher dimensions.

关键词： Coefflcient multipliers mixed norm spaces holomorphic functions.

BERGMAN TYPE OPERATOR ON MIXED NORM SPACES WITH APPLICATIONS

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Chinese Annals of mathematics,Series B 1997年第3期18卷 265-276页

作者： ren {1. SHI JIHUAI department of {1. University of Science and Technology of ChinaHefei 230026China

The authors investigate the conditions for the boundedness of Bergman type operators Ps,t in mixed norm space L_(p),q(φ)on the unit ball of C^(n)(n≥1.,and obtain a sufficient condition and a necessary condition for general normal functionφ,and a sufficient and necessary condition forφ(r)=(1.r 2)αlogβ(2(1.r)-1.(α>0,β≥0).This generalizes the result of Forelli Rudin on Bergman operator in Bergman *** applications,a more natural method is given to compute the duality of the mixed norm space,solve the Gleason's problem for mixed norm space and obtain the characterization of mixed norm space in terms of partial ***,it is proved thatf∈L(0)∞,q(φ)iff all the functions(1.|z|2)|α||α|fzα(z)∈L(0)∞,q(φ)for holomorphic functionf,1.q≤∞.

关键词： Bergman projection Normal function Mixed norm space

High-Performance and Large-Area Inverted Perovskite Solar Cells Based on NiO_(x) Films Enabled with A Novel Microstructure-Control technology

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Energy & Environmental Materials 2024年第1期7卷 153-159页

作者： Guibin Shen Xin Li Yuqin Zou Hongye Dong Dongping Zhu Yanglin Jiang Xin ren Ng Fen Lin Peter Müller-Buschbaum Cheng Mu Key Laboratory of Advanced Light Conversion Materials and Biophotonics Department of ChemistryRenmin University of ChinaBeijing 100872China Solar Energy Research Institute of Singapore(SERIS) National University of SingaporeSingapore 117574Singapore Physik-department Lehrstuhl für Funktionelle MaterialienTechnische Universität MünchenJames-Franck-Straße 185748Garching Germany Heinz Maier-Leibnitz Zentrum(MLZ) Technische Universität MünchenLichtenbergstr.185748Garching Germany

The improvement in the efficiency of inverted perovskite solar cells(PSCs)is significantly limited by undesirable contact at the NiO_(x)/perovskite *** this study,a novel microstructure-control technology is proposed for fabrication of porous NiO_(x)films using Pluronic P1.3 as the structure-directing agent and acetylacetone(AcAc)as the coordination *** synthesized porous NiO_(x)films enhanced the hole extraction efficiency and reduced recombination defects at the NiO_(x)/perovskite ***,without any modification,the power conversion efficiency(PCE)of the PSC with MAPbl_(3)as the absorber layer improved from 1..50%to 1..08%.Moreover,the PCE of the device composed of perovskite Cs0.05(MA_(0.1.)FA_(0.85))_(0.95)Pb(I_(0.85)Br_(0.1.))_(3)improved from 1..49%to 21.42%.Furthermore,the application of the fabricated porous NiO_(x)on fluorine-doped tin oxide(FTO)substrates enabled the fabrication of large-area PSCs({1. cm^(2))with a PCE of 1..63%.This study provides a novel strategy for improving the contact at the NiO_(x)/perovskite interface for the fabrication of high-performance large-area perovskite solar cells.

关键词： interfacial contact inverted and large-area perovskite solar cells photovoltaic materials porous NiO_(x)films renewable energy

Physics package based on intracavity laser cooling ^(87)Rb atoms for space cold atom microwave clock

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Chinese Physics B 2024年第7期33卷 22-26页

作者：邓思敏达任伟项静峰赵剑波李琳张迪万金银孟艳玲蒋小军李唐刘亮吕德胜 Aerospace Laser technology and System {1. Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Mechanics Chinese Academy of SciencesShanghai 201800China Center of Materials science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

This article proposes a new physics package to enhance the frequency stability of the space cold atom clock with the advantages of a microgravity environment. Clock working processes, including atom cooling, atomic state preparation,microwave interrogation, and transition probability detection, are integrated into the cylindrical microwave cavity to achieve a high-performance and compact physics package for the space cold atom clock. We present the detailed design and ground-test results of the cold atom clock physics package in this article, which demonstrates a frequency stability of 1.2×1.^(-􀀀1.) τ^(-1.2) with a Ramsey linewidth of 1..5 Hz, and a better performance is predicted with a 1.Hz or a narrower Ramsey linewidth in microgravity environment. The miniaturized cold atom clock based on intracavity cooling has great potential for achieving space high-precision time-frequency reference in the future.

关键词： atomic clock microgravity microwave cavity space station frequency stability

紫外光辅助MnFe_(2)O_(4)@活性炭活化过硫酸盐降解盐酸四环素

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无机化学学报 2024年第10期40卷 1869-1880页

作者：李建军任明杰张梨梨曾玲玲王慧玲孟祥武安徽理工大学材料科学与工程学院淮南232001 安徽康达检测技术有限公司芜湖241000 安徽省煤基固废新材料产业共性技术研究中心淮南232001

通过水浴-逆共沉淀法制备磁性催化剂MnFe_(2)O_(4)@AC(MFA),并对其结构和磁性进行了系统表征。结果显示,MnFe_(2)O_(4)纳米颗粒包覆在活性炭(AC)表面,构成了多级孔结构。MFA较AC基体材料的比表面积有所下降,但仍高达1.6 m^(2)·g^(-1.,... 详细信息

通过水浴-逆共沉淀法制备磁性催化剂MnFe_(2)O_(4)@AC(MFA),并对其结构和磁性进行了系统表征。结果显示,MnFe_(2)O_(4)纳米颗粒包覆在活性炭(AC)表面,构成了多级孔结构。MFA较AC基体材料的比表面积有所下降,但仍高达1.6 m^(2)·g^(-1.,平均孔径为8.49 nm。MFA的比磁化强度高达38.92 emu·g^(-1.,可利用外磁场实现高效固液分离。以MFA为催化剂,在紫外光辅助下活化过硫酸氢钾(PMS)降解盐酸四环素(TC)。研究表明,在紫外光辐照下MFA/PMS体系对TC降解率能够达到97.70%,是无紫外光照射体系的1.2倍;共存阴离子、药剂制度、TC初始质量浓度等因素对系统的催化性能具有显著影响。循环5次之后,降解率仍可达到82.76%。自由基猝灭实验表明,超氧自由基(·O_(2)^(-))和单线态氧(^(1.O_(2))是紫外光辅助MFA/PMS高级氧化体系中的主要活性氧。机理分析表明,MFA的高吸附性为催化降解提供了良好的基础,紫外光辐照和MFA/PMS高级氧化体系的协同效应可显著提升活性基团的生成效率,从而促进了有机分子的降解。

关键词：高级氧化过硫酸盐紫外光辅助活性炭铁氧体活性氧