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第二类广义华罗庚域上从α-Bloch空间到Bers型空间的加权复合算子的有界性和紧性
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作者 苏简兵 王子燕 《江苏师范大学学报(自然科学版)》 CAS 2024年第3期39-48,共10页
本文在第二类广义华罗庚域上定义了加权Bloch空间和Bers型空间,并讨论了从α-Bloch空间到Bers型空间之间的加权复合算子的有界性和紧性,得到了该加权复合算子是有界算子或紧算子的充分条件和必要条件.
关键词 广义华罗庚域 BLOCH空间 bers型空间 加权复合算子 有界性和紧性
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The case-dependent lignin role in lignocellulose nanofibers preparation and functional application-A review
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作者 Xiya Zhang Lili Zhang +1 位作者 Yimin Fan Zhiguo Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第6期1553-1566,共14页
Lignocellulose nanofibers(LCNFs) as a new material is attracting extensive attention. The pretreatment and mechanical fibrillation are the two main stages involved in the preparation of LCNFs, and lignin plays the imp... Lignocellulose nanofibers(LCNFs) as a new material is attracting extensive attention. The pretreatment and mechanical fibrillation are the two main stages involved in the preparation of LCNFs, and lignin plays the important role of these two stages. This review discussed the interaction between lignin and chemicals in the pretreatment stage, and discovered the general law of the effect of lignin in the mechanical fibrillation stage.Lignin exhibits both promotion and inhibition effects on mechanical fibrillation, and the mutual competition between the two effects ultimately affects the energy consumption, morphology and yield of LCNFs. Furthermore, the recent research progress related to the contributions of lignin on the functional application of LCNFs was summarized, aiming to provide profound guidance for the preparation and application of LCNFs. 展开更多
关键词 Lignocellulose nanofibers LIGNIN FIBRILLATION CELLULOSE PRETREATMENT
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Characterization of Unsaturated Polyester Filled with Waste Coconut Shells, Walnut Shells, and Carbon Fibers
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作者 Marwah Subhi Attallah Reem Alaa Mohammed Ruaa Haitham Abdel-Rahim 《Fluid Dynamics & Materials Processing》 EI 2023年第10期2449-2469,共21页
This study aims to evaluate the erosion behavior and the hardness of hybrid composites made of varying amounts of coconut shells,walnut shells,and carbonfibers dispersed in a polyester matrix.MINITAB(L16)Taguchi experi... This study aims to evaluate the erosion behavior and the hardness of hybrid composites made of varying amounts of coconut shells,walnut shells,and carbonfibers dispersed in a polyester matrix.MINITAB(L16)Taguchi experiments were used to determine the optimal combination of parameters.In particular,an erosion device con-sisting of a motor with a constantflow rate of 45 L/min,a pump with a diameter of 40 mm,a nozzle with a dia-meter of 5 mm,and a tank made of“perspex glass”55 cm long,30 cm tall,and 25 cm wide was used.The tests were conducted by varying the sample-to-nozzle distance,the pattern angle,and the sand particle size.The results have revealed that the presence of 7.5%by weight of waste coconut shell,for conditions corresponding to 90°angle,sand size 425μm,stand distance 30 cm,gives the best wear resistance(3.04×10^(-5) g/g).Thefiller content and sand particle size affect the erosive rate,with the angle playing a secondary role.The distance between the sample and the nozzle has a weaker effect on erosive wear.The hardness results show that the models(UP-5%carbonfiber-2.5-3.5-4.5-5.5-6.5-7.5 wt.%waste coconut shell)give the best values for prayer compared to the samples(UP-5 wt.%carbonfiber-2.5-3.5-4.5-5.5-6.5-7.5 wt.%waste walnut shell). 展开更多
关键词 Unsaturated polyester resin carbonfiber waste coconut shell walnut shell erosive behavior Taguchi’s method L16
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不同Bers型空间之间的加权复合算子 被引量:4
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作者 王茂发 刘云 《数学物理学报(A辑)》 CSCD 北大核心 2007年第4期665-671,共7页
该文讨论了单位圆盘上不同Bers型空间之间的加权复合算子的有界性、紧性和弱紧性,给出了一些充分必要的判别条件,特别地得到不同Bers型空间上加权复合算子的紧性与弱紧性的等价性.这些推广了经典的复合算子与乘法算子的相关结论.该文同... 该文讨论了单位圆盘上不同Bers型空间之间的加权复合算子的有界性、紧性和弱紧性,给出了一些充分必要的判别条件,特别地得到不同Bers型空间上加权复合算子的紧性与弱紧性的等价性.这些推广了经典的复合算子与乘法算子的相关结论.该文同时也给出了Bers型空间上复合算子的Fredholm性和闭值域问题的刻画,完善了文献[6]中结论. 展开更多
关键词 加权复合算子 FREDHOLM算子 bers型空间 闭值域 有界性 弱紧性
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单位球上Bers型空间之间的加权复合算子
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作者 金丽娜 唐笑敏 《湖州师范学院学报》 2009年第2期22-25,共4页
为了研究Cn中单位球上Bers型空间及小Bers型空间之间加权复合算子uCφ的有界性和紧性特征,利用泛函分析和复分析的方法,获得了uCφ为有界算子或紧算子的若干充要条件,得到了uCφ在上述空间之间的范数估计.
关键词 bers型空间 bers型空间 加权复合算子 单位球
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一致完全域,Bers空间与自由插值
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作者 沈燮昌 肖杰 《北京大学学报(自然科学版)》 CAS CSCD 北大核心 1993年第5期537-544,共8页
设Ω是C中的双曲型区域,λ_Ω(z)|dz|为其上的双曲(Poincar(?))度量。令δ_Ω(z)=dist(z,Ω)及[δ_Ω(z)]^(-1)·|dz|为Ω上的拟双曲度量。又置A_λ~∞(Ω)和A_δ~∞(Ω)分别是具有范数‖f‖_λ=|f(z)|·[λ_Ω(z)]^(-1)<∞... 设Ω是C中的双曲型区域,λ_Ω(z)|dz|为其上的双曲(Poincar(?))度量。令δ_Ω(z)=dist(z,Ω)及[δ_Ω(z)]^(-1)·|dz|为Ω上的拟双曲度量。又置A_λ~∞(Ω)和A_δ~∞(Ω)分别是具有范数‖f‖_λ=|f(z)|·[λ_Ω(z)]^(-1)<∞和‖f‖_δ|f(z)|δ_Ω(z)<∞的Ω上解析函数f之全体。在本文,一致完全域Ω,即满足C(Ω)=infλ_Ω(z)δ_Ω(z)>0的域Ω被研究,进而A_λ~∞(Ω)与A_δ~∞(Ω)中的函数被刻划;最后就单连通区域Ω上的A_λ~∞(Ω)=A_δ~∞(Ω)中的自由插值问题也被考虑。 展开更多
关键词 bers空间 自由插值 一致完全域
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Bers型空间之间的加权微分复合算子 被引量:3
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作者 吴莹颖 张若静 唐笑敏 《江西师范大学学报(自然科学版)》 CAS 北大核心 2011年第6期610-613,共4页
给定复平面中单位圆盘D上的全纯自映射,设u∈H(D),定义H(D)上的加权微分复合算子,Dnφu为(Dnφuf)(z)=u(z).f(n)(φ(z)),f∈H(D),z∈D.利用泛函分析和复分析的方法,讨论了Bers型空间(或小Bers型空间)之间加权微分复合算子,Dnφu的有界... 给定复平面中单位圆盘D上的全纯自映射,设u∈H(D),定义H(D)上的加权微分复合算子,Dnφu为(Dnφuf)(z)=u(z).f(n)(φ(z)),f∈H(D),z∈D.利用泛函分析和复分析的方法,讨论了Bers型空间(或小Bers型空间)之间加权微分复合算子,Dnφu的有界性和紧性,得到了若干充要条件. 展开更多
关键词 bers型空间 加权微分复合算子 有界性 紧性
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小Bloch型空间到小Bers型空间的加权复合算子(英文)
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作者 陈凡 唐笑敏 《湖州师范学院学报》 2013年第3期9-13,共5页
给定单位球上的全纯函数u和单位球上的全纯自映射φ,讨论了小Bloch型空间到小Bers型空间的加权复合算子uCφ的有界性和紧性,给出了uCφ为有界算子或紧算子的充要条件.
关键词 正规权 小Bloch型空间 bers型空间 加权复合算子
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Cu-Al-O Nanofibers Fabricated by Electrospinning and Their Ozone Sensing Properties at Room Temperature 被引量:1
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作者 吕默 CAO Jiajia +2 位作者 WANG Yu SHEN Hongzhi 王一丁 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第3期463-466,共4页
Cu-Al-O nanofibers are synthesized by an electrospinning method. After electrospinning process, these nanofi bers were thermally treated at different temperatures from 900 to 1 100 ℃. The morphology and crystal struc... Cu-Al-O nanofibers are synthesized by an electrospinning method. After electrospinning process, these nanofi bers were thermally treated at different temperatures from 900 to 1 100 ℃. The morphology and crystal structure of the fi bers were analyzed by scanning electron microscopy and X-ray diffraction. Thick fi lm gas sensors were fabricated by spinning the nanofi bers on a ceramic substrate with Au-Pt interdigitated electrodes. These sensors exhibited high ozone sensing properties at room temperature. When the sensors were exposed to 100 ppm ozone, the response time was about 2.74 s, and the recovery was about 12.68 s. 展开更多
关键词 ELECTROSPINNING Cu-Al-O nanofi bers ozone sensor
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Bers型空间上加权复合微分前置算子
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作者 余建 《科技风》 2017年第6期39-40,共2页
从算子的性质出发,研究Bers型空间上的复合微分前置算子的有界性和紧性,得到了算子有界性和紧性的充分必要条件。
关键词 bers型空间 复合微分前置算子 有界性 紧性
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双曲型区域上带权Bers空间QA ̄α(Ω)的渐近性质
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作者 王卫 《北京大学学报(自然科学版)》 CAS CSCD 北大核心 1995年第3期309-315,共7页
设ΩC是双曲型区域,λ_Ω(z)|dz|是Ω上的双曲度量。δ_Ω(z)=dist(z,Ω),称[δ_Ω(z)]^(-α)·|dz|为Ω上的α-拟双曲度量。这篇文章主要讨论在α-拟双曲度量下定义的函数空间QA~α(Ω... 设ΩC是双曲型区域,λ_Ω(z)|dz|是Ω上的双曲度量。δ_Ω(z)=dist(z,Ω),称[δ_Ω(z)]^(-α)·|dz|为Ω上的α-拟双曲度量。这篇文章主要讨论在α-拟双曲度量下定义的函数空间QA~α(Ω),QB~α(Ω)和QT~α(Ω)的渐近性质以及与双曲度量意义下类似的函数空间的关系。 展开更多
关键词 双曲型区 双曲度量 bers空间 渐近性质
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第一类Cartan-Hartogs域上的Bers型空间上的加权复合算子
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作者 柏宏斌 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2022年第4期31-36,共6页
设Y_(I)(N,m,n;K)是第一类Cartan-Hartogs域,φ是Y_(I)(N,m,n;K)上的全纯自映射,H(Y_(I)(N,m,n;K))是Y_(I)(N,m,n;K)上的全纯函数集合,u∈H(Y_(I)(N,m,n;K)).本文运用Y_(I)(N,m,n;K)上的广义华-矩阵不等式给出了Y_(I)(N,m,n;K)上的Bers... 设Y_(I)(N,m,n;K)是第一类Cartan-Hartogs域,φ是Y_(I)(N,m,n;K)上的全纯自映射,H(Y_(I)(N,m,n;K))是Y_(I)(N,m,n;K)上的全纯函数集合,u∈H(Y_(I)(N,m,n;K)).本文运用Y_(I)(N,m,n;K)上的广义华-矩阵不等式给出了Y_(I)(N,m,n;K)上的Bers型空间上的加权复合算子W_(φ,μ)的有界性和紧致性的刻画. 展开更多
关键词 加权复合算子 广义Hua-矩阵不等式 第一类Cartan-Hartogs域 bers型空间 有界性 紧致性
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Q_K-Teichmüller空间的Bers嵌入
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作者 唐树安 《数学杂志》 2020年第2期210-218,共9页
本文研究Q_K-Teichmüller空间的Bers投影和预投影.利用拟共形映射理论,证明了Q_KTeichmüller空间的Bers投影和预投影是全纯的.
关键词 拟对称映射 万有Teichmuller空间 QK-Teichmüller空间 bers投影
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Properties and Microstructure of Polymer Emulsions Modifi ed Fibers Reinforced Cementitious Composites 被引量:4
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作者 吴英 孙乾耀 +1 位作者 KONG Lian FANG He 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第4期795-802,共8页
The synthesis and characterization of a new class of cementitious composites filled with polymer emulsions were investigated, and their superior mechanical strength and durability properties compared to composites dev... The synthesis and characterization of a new class of cementitious composites filled with polymer emulsions were investigated, and their superior mechanical strength and durability properties compared to composites devoid of fi llers were reported. Polymer emulsions were utilized to mechanically reinforce the composite and bridge the cement, fly ash, aggregate and fibers. The results reveal that the epoxy emulsion and poly(ethylene-co-vinyl acetate) emulsion markedly enhance the mechanical and durability properties of cemetitious composites. The fi bers can be pulled out in the form of slip-hardening and the abrasion phenomenon can be observed clearly on the surface of the fibers. The hydration extent of cement is higher than that of the pristine composites. The polymer modified cementitious composites designed on micromechanics, have fl exibility and plasticity which could be applied for a novel form of multifunctional materials with a range of pipeline coatings applications. 展开更多
关键词 polymer emulsion cementitious composites fi ber microstructure
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Chemical fibers Seeking a new route for development
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作者 Zhao Zihan 《China Textile》 2015年第10期14-19,共6页
The 21st China International Man-made Fi- ber Conference (CIMFC), themed on "innovation- driven, integrative development -- the main theme of the development of chemical fiber industry in the 'New normal' " and ... The 21st China International Man-made Fi- ber Conference (CIMFC), themed on "innovation- driven, integrative development -- the main theme of the development of chemical fiber industry in the 'New normal' " and focused on new strategies for the transformation and new initiatives for integrative development of global chemical fiber industry, was convened in Shengze Jiangsu province fromSeptember 7th to 9th, 2015. China Textile gave a brief introduction to the conference in the last issue and is sharing the detailed reports to our readers in this issue, 展开更多
关键词 化学纤维 路线 一体化发展 人造纤维 工业发展 BER 江苏省 纺织品
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从单位球上Bergman型空间到Bers型空间的加权复合算子 被引量:2
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作者 周锋 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第2期294-298,共5页
本文利用Bergman型空间A_ω~p中函数值的估计,通过构造一些新的测试函数,得到了多复平面C^n中单位球上Bergman型空间A_ω~p到B3ers型空间H_v~∞、小Bers型空间H_v^0的加权复合算子有界性和紧性的充要条件,此外,还获得了Bloch型空间上有... 本文利用Bergman型空间A_ω~p中函数值的估计,通过构造一些新的测试函数,得到了多复平面C^n中单位球上Bergman型空间A_ω~p到B3ers型空间H_v~∞、小Bers型空间H_v^0的加权复合算子有界性和紧性的充要条件,此外,还获得了Bloch型空间上有界复合算子的谱. 展开更多
关键词 单位球 Bergman型空间 bers型空间 加权复合算子
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Bergman型空间到Bers型空间之加权复合算子 被引量:2
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作者 江治杰 《数学学报(中文版)》 SCIE CSCD 北大核心 2010年第1期67-74,共8页
讨论了Bergman型空间H(p,μ)到Bers型空间Hβ^∞、小Bers型空间Hβ,0^∞上的加权复合算子,给出了加权复合算子有界性、紧性、弱紧性的充要条件,以及紧复合算子的角导数准则.本文还讨论了具有闭值域的加权复合算子,得到了一个充分条件.
关键词 Bergman型空间 bers型空间 加权复合算子
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Mechanical Behavior of Panels Reinforced with Orthogonal Plant Fabrics: Experimental and Numerical Assessment
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作者 Martha L.Sánchez G.Capote 《Journal of Renewable Materials》 EI CAS 2024年第10期1791-1810,共20页
The construction sector is one of the main sources of pollution,due to high energy consumption and the toxic substances generated during the processing and use of traditional materials.The production of cement,steel,a... The construction sector is one of the main sources of pollution,due to high energy consumption and the toxic substances generated during the processing and use of traditional materials.The production of cement,steel,and other conventional materials impacts both ecosystems and human health,increasing the demand for ecological and biodegradable alternatives.In this paper,we analyze the properties of panels made from a combination of plant fibers and castor oil resin,analyzing the viability of their use as construction material.For the research,orthogonal fabrics made with waste plant fibers supplied by a company that deals with the manufacture of furniture and craft products were used.These fabrics were made with strips of plant fibers of the Calamus rotang,Bambusa vulgaris,Heteropsis flexuosa,and Salix viminalis species.To improve their compatibility with the castor oil resin,a cold argon plasma treatment was applied.The effect of the treatment on the properties of the fibers and the panels was analyzed.The density,water absorption capacity,and swelling percentage were evaluated.Tensile,compression,static bending,and linear buckling tests were carried out.The study found that panels made with treated fiber fabrics exhibited a reduction of approximately 10%in absorption capacity and up to 35%in swelling percentage values.Panels made with Bambusa vulgaris fabrics exhibited the highest strength and stiffness values.Numerical models were constructed using commercial finite element software.When comparing the numerical results with the experimental ones,differences of less than 15%were seen,demonstrating that the models allow adequately predicting the analyzed properties.On comparing the values obtained with the characteristic values of oriented strand board,the results suggest that panels made with unconventional materials could replace commercial panels traditionally made with wood-based fibers and particles and other composite materials in several applications in the construction industry. 展开更多
关键词 Unconventional materials nonstructural panels plantfibers surface treatment physical properties mechanical properties
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Performance Analysis of Plant Shells/PVC Composites under Corrosion and Aging Conditions
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作者 Haoping Yao Xinyu Zhong Chunxia He 《Journal of Renewable Materials》 EI CAS 2024年第5期993-1006,共14页
To make full use of plant shellfibers(rice husk,walnut shell,chestnut shell),three kinds of wood-plastic com-posites of plant shellfibers and polyvinyl chloride(PVC)were prepared.X-ray diffraction analysis was carried o... To make full use of plant shellfibers(rice husk,walnut shell,chestnut shell),three kinds of wood-plastic com-posites of plant shellfibers and polyvinyl chloride(PVC)were prepared.X-ray diffraction analysis was carried out on three kinds of plant shellfibers to test their crystallinity.The aging process of the composites was conducted under 2 different conditions.One was artificial seawater immersion and xenon lamp irradiation,and the other one was deionized water spray and xenon lamp irradiation.The mechanical properties(tensile strength,flexural strength,impact strength),changes in color,water absorption,Fourier transform infrared spectroscopy(FTIR),and microstructures of the composites before and after the two aging experiments were analyzed.The results showed that the chestnut shell had the highest crystallinity,which was 42%.The chestnut shell/PVC composites had the strongest interface bonding,the least internal defects,and the best general mechanical properties among the three composites.Its tensile strength,bending strength and impact strength were 23.81 MPa,34.12 MPa,and 4.32 KJ·m^(-2),respectively.Comparing the two aging conditions,artificial seawater immersion and xenon lamp irradiation destroyed the quality of the combination of plant shellfibers and PVC,making the internal defects of the composites increase.This made the water absorption ability and changes in the color of the composites more obvious and led to a great decrease in the mechanical properties.The general mechanical properties of the chestnut shell/PVC composites were the best,but their water absorption ability changed more obviously. 展开更多
关键词 Plant shellfibers polyvinyl chloride wood-plastic composites artificial seawater immersion deionized water spray xenon lamp irradiation
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关于Poincaré度量与Bers逼近定理
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作者 张学莲 《数学学报(中文版)》 SCIE CSCD 北大核心 1997年第4期545-550,共6页
本文首先给出区域D的Poincaré度量λ(z)的几个有关性质,然后推广Bers逼近定理,得到主要结果如下:设D是连通数为有穷的有界区域,记Aq(D)为D内满足||p||=∫∫_D[λ(z) ̄(2-9)|ψ(z)... 本文首先给出区域D的Poincaré度量λ(z)的几个有关性质,然后推广Bers逼近定理,得到主要结果如下:设D是连通数为有穷的有界区域,记Aq(D)为D内满足||p||=∫∫_D[λ(z) ̄(2-9)|ψ(z)||dz∧dz<∞的解析函数ψ之全体构成的Banach空间(其中整数q≥2),Rq(D,T)(TC(c-D))表示Aq(D)中极点在T的有理函数子空间,当T满足Bers逼近定理条件时,Rq(D,T)在Aq(D)中稠密。 展开更多
关键词 解析函数 稠密 庞加莱度量 bers逼近定理
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