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Three-dimensionally ordered macroporous cross-linked polystyrene incorporating functional group via hydrophilic spacer arm 被引量:1
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作者 Li Xia Yuan Xiao Mei Wang Xu Zhang Pan Ge Liu Wei Dong Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第12期1493-1496,共4页
A versatile and effective method for incorporating functional groups on the pore wall of three-dimensionally ordered macroporous cross-linked polystyrene(3DOM CLPS) by hydrophilic spacer arm has been investigated.Th... A versatile and effective method for incorporating functional groups on the pore wall of three-dimensionally ordered macroporous cross-linked polystyrene(3DOM CLPS) by hydrophilic spacer arm has been investigated.The 3DOM CLPS with pore size 865 nm was prepared by sacrifice template method.The hydrophilic spacer arm(polyethylene glycol,molecular weight is 600) was grafted to the 3DOM CLPS via nucleophilic substitution reaction.The other side of active hydroxyl can be further converted into a lot of other functional groups.In this report,the chelating ligand 2-mercaptobenzothiazole(MBZ) group was introduced on the end of the PGE chain to evidence the versatile functionalization approach.The functionalized ordered macroporous materials were characterized by FT-IR,element analyzer,SEM.The results reveal that the pores were successfully bonded with 2-mercaptobenzothiazole groups via hydrophilic spacer arms and the original morphology of ordered macroporous materials were remained after functionalization.The MBZ group density is 0.052 mmol/m^2.The functionalized 3DOM CLPS are expected to application as heavy metal ions adsorbent. 展开更多
关键词 Three-dimensionally ordered macroporous polymer FUNCTIONALIZATION Hydrophilic space arm Heterocyclic functional group
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A study on distributive and modular lattice ordered fuzzy soft group and its duality
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作者 J Arockia Reeta J Vimala 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2016年第4期491-502,共12页
Soft set theory has a rich potential application in several fields. A soft group is a parameterized family of subgroups and a fuzzy soft group is a parameterized family of fuzzy subgroups. The concept of fuzzy soft gr... Soft set theory has a rich potential application in several fields. A soft group is a parameterized family of subgroups and a fuzzy soft group is a parameterized family of fuzzy subgroups. The concept of fuzzy soft group is the generalization of soft group. Abdulkadir Aygunoglu and Halis Aygun introduced the notion of fuzzy soft groups in 2009[1]. In this paper, the concept of lattice ordered fuzzy soft groups and its duality has been introduced. Then distributive and modular lattice ordered fuzzy soft groups are analysed. The objective of this paper is to study the lattice theory over the collection of fuzzy soft group in a parametric manner. Some pertinent properties have been analysed and hence established duality principle. 展开更多
关键词 Fuzzy soft set fuzzy soft group lattice ordered fuzzy soft groups distributive lattice orderedfuzzy soft groups modular lattice ordered fuzzy soft groups.
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Maximal Above and Below Pairs of Abelian Fully Ordered Groups
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作者 郑熙强 《Northeastern Mathematical Journal》 CSCD 2000年第4期445-450,共6页
In this paper, maximal above and below pairs of fully ordered groups (o groups) are studied. It is shown that maximal above and below pairs of an divisible abelian o group have some specific properties, and by using... In this paper, maximal above and below pairs of fully ordered groups (o groups) are studied. It is shown that maximal above and below pairs of an divisible abelian o group have some specific properties, and by using these properties another embedding method of an abelian o group to real valued functions is discussed. 展开更多
关键词 ordered group convex subgroup above and below subgroup
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Endpoints of Multi-Valued Weak Contractions on the Metric Space of Partially Ordered Groups
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作者 Congdian Cheng 《Advances in Pure Mathematics》 2022年第11期638-651,共14页
The present work considers the endpoint in the abstract metric space. It firstly introduces the metric space of partially ordered groups and the metric space of partially ordered modules, respectively;and defines the ... The present work considers the endpoint in the abstract metric space. It firstly introduces the metric space of partially ordered groups and the metric space of partially ordered modules, respectively;and defines the convergence of sequences and the multi-valued weak contractions, etc., on the introduced space. And then, with the methods of functional analysis and abstract algebra, it successively establishes an endpoint theorem for the metric space of partially ordered groups and an endpoint theorem for the metric space of partially ordered modules. The contributions of this article extend the theory of cone metric space constructed by Huang and Zhang (2007) and some recent results on the fixed point and endpoint theory, such as the endpoint theorem given by Amini-Harandi (2010). 展开更多
关键词 Fixed Point Endpoint Metric Space Valued in Partially ordered group Topological Structure Weak Contraction
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乌鲁木齐市居民幸福感组群差异分析——基于Ordered Logistic模型 被引量:1
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作者 肖春梅 霍露萍 《新疆财经》 2015年第6期72-78,共7页
为了解居民对当前生活的满意度情况,本文选取乌鲁木齐市居民为研究样本,采用调查问卷及访谈的方式对其经济状况、社会安全、政府公共服务等方面的满意度情况进行了调查。运用Ordered Logistic模型对居民幸福感影响因素和组群差异进行分... 为了解居民对当前生活的满意度情况,本文选取乌鲁木齐市居民为研究样本,采用调查问卷及访谈的方式对其经济状况、社会安全、政府公共服务等方面的满意度情况进行了调查。运用Ordered Logistic模型对居民幸福感影响因素和组群差异进行分析。结果得出:经济状况、社会安全和政府公共服务三个因素均对居民幸福感具有显著影响;不同职业和不同月收入水平的居民对各影响因素的满意度不同。为此本文提出,应大力发展乌鲁木齐市经济,以提高居民生活水平;加强社会治安,为居民营造平安生活环境;美化周围环境,建设生态文明城市;完善社会保障制度,以提高居民幸福感。 展开更多
关键词 幸福感 ordered LOGISTIC 组群差异 乌鲁木齐
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A RECOGNITION OF SIMPLE GROUPS PSL(3,q) BY THEIR ELEMENT ORDERS 被引量:2
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作者 M.R.Darafsheh A.R.Moghaddamfar A.R.Zokayi 《Acta Mathematica Scientia》 SCIE CSCD 2004年第1期45-51,共7页
For any group G, denote byπe(G) the set of orders of elements in G. Given a finite group G, let h(πe (G)) be the number of isomorphism classes of finite groups with the same set πe(G) of element orders. A group G i... For any group G, denote byπe(G) the set of orders of elements in G. Given a finite group G, let h(πe (G)) be the number of isomorphism classes of finite groups with the same set πe(G) of element orders. A group G is called k-recognizable if h(πe(G)) = k <∞, otherwise G is called non-recognizable. Also a 1-recognizable group is called a recognizable (or characterizable) group. In this paper the authors show that the simple groups PSL(3,q), where 3 < q≡±2 (mod 5) and (6, (q-1)/2) = 1, are recognizable. 展开更多
关键词 Element order prime graph projective special linear group
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Two Important Classes of p-groups and the Orders of Their Automorphism Groups 被引量:2
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作者 BAN Gui-ning ZHANG Xin-zheng 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期491-493,共3页
In the paper we obtain two infinite classes of p-groups, calculate the orders of their automorphism groups and correct a mistake(perhaps misprinted) of Rodney James' paper in 1980.
关键词 finite group P-group AUTOMORPHISM order CLASSIFICATION
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Orders of Automorphism Groups of the p^6 Groups of Family Φ_(24) 被引量:1
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作者 赵振华 苏翃 邱利琼 《Journal of Southwest Jiaotong University(English Edition)》 2008年第4期419-423,共5页
Using the metabelian property, regularity, p-commutativity and some properties of congruence, this paper gave the orders of automorphism groups of family Ф24, which are the groups of order p^6 determined by Rodney Ja... Using the metabelian property, regularity, p-commutativity and some properties of congruence, this paper gave the orders of automorphism groups of family Ф24, which are the groups of order p^6 determined by Rodney James, where p denotes an odd prime. 展开更多
关键词 P-group AUTOMORPHISM Defining relations order
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Orders of Automorphism Groups of Some p-Groups
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作者 苏翃 赵振华 +1 位作者 肖志祥 邱敦元 《Journal of Southwest Jiaotong University(English Edition)》 2008年第2期199-204,共6页
The orders of automorphism groups of the groups of order p^6 in the twelve family Ф12 axe produced, where p is an odd prime. Every group is analysed by utilizing the properties of metabelian, regularity and p-commuta... The orders of automorphism groups of the groups of order p^6 in the twelve family Ф12 axe produced, where p is an odd prime. Every group is analysed by utilizing the properties of metabelian, regularity and p-commutativity of finite p-groups, and the structure of the generators of its automorphism groups is obtained. Then the orders of automorphism groups are determined through some properties of equivalence in number theory. 展开更多
关键词 Finite group order Definite relation Automorphism group
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The Class of Orderable Groups Is a Quasi-Variety with Undecidable Theory
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作者 Benjamin Fine Anthony Gaglione +1 位作者 Gerhard Rosenberger Dennis Spellman 《Advances in Pure Mathematics》 2021年第3期180-186,共7页
Let <em>G</em> be a group. <em>G</em> is right-orderable provided it admits a total order ≤ satisfying <em>hg</em><sub>1</sub> <span style="white-space:normal;&... Let <em>G</em> be a group. <em>G</em> is right-orderable provided it admits a total order ≤ satisfying <em>hg</em><sub>1</sub> <span style="white-space:normal;">≤ <span style="white-space:normal;"><em>hg</em><sub>2 </sub></span></span>whenever <em style="white-space:normal;">g</em><sub style="white-space:normal;">1</sub><span style="white-space:normal;"> </span><span style="white-space:normal;">≤ <i>g</i><sub>2</sub></span>. <em>G</em> is orderable provided it admits a total order ≤ satisfying both: <em style="white-space:normal;">hg</em><sub style="white-space:normal;">1</sub><span style="white-space:normal;"> </span><span style="white-space:normal;">≤ <em>hg</em><sub>2</sub></span> whenever <span style="white-space:nowrap;"><em>g</em><sub>1</sub> ≤ <em>g</em><sub>2</sub></span> and <em style="white-space:normal;">g</em><sub style="white-space:normal;">1</sub><em style="white-space:normal;">h</em><span style="white-space:normal;"> ≤ </span><em style="white-space:normal;">g</em><sub style="white-space:normal;">2</sub><em style="white-space:normal;">h</em> whenever <em>g</em><sub>1</sub> ≤ <em>g</em><sub>2</sub>. A classical result shows that free groups are orderable. In this paper, we prove that left-orderable groups and orderable groups are quasivarieties of groups both with undecidable theory. For orderable groups, we find an explicit set of universal axioms. 展开更多
关键词 orderable group Left orderable group Quasi-Variety
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REVERSE ORDER LAW FOR GROUP INVERSE OF PRODUCT OF MATRICES ON SKEW FIELDS
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作者 Liu Yu (Dept.of Math.,Hulan Teacher College,Hulan 150500,PRC)Cao Chongguang(Dept.of Math.,Heilongjiang University,Harbin 150080,PRC) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第S1期38-39,共2页
Let K<sup>n×n</sup> be the set of all n×n matrices and K<sub>r</sub><sup>n×n</sup> the set {A∈K<sup>n×n</sup>|rankA=r} on askew field K. Zhuang [1] ... Let K<sup>n×n</sup> be the set of all n×n matrices and K<sub>r</sub><sup>n×n</sup> the set {A∈K<sup>n×n</sup>|rankA=r} on askew field K. Zhuang [1] denotes by A<sup>#</sup> the group inverse of A∈K<sup>n×n</sup> which is the solu-tion of the euqations:AXA=A, XAX=X, AX=AX. 展开更多
关键词 MATH RI RD REVERSE order LAW FOR group INVERSE OF PRODUCT OF MATRICES ON SKEW FIELDS OI AB
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Evaluate All the Order of Every Element in the Higher Order of Group for Addition and Multiplication Composition
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作者 Md. Abdul Mannan Nazmun Nahar +3 位作者 Halima Akter Momtaz Begum Md. Amanat Ullah Shabnam Mustari 《International Journal of Modern Nonlinear Theory and Application》 2022年第2期11-30,共20页
This paper aims at treating a study on the order of every element for addition and multiplication composition in the higher order of groups for different algebraic structures as groups;order of a group and order of el... This paper aims at treating a study on the order of every element for addition and multiplication composition in the higher order of groups for different algebraic structures as groups;order of a group and order of element of a group in real numbers. Here we discuss the higher order of groups in different types of order which will give us practical knowledge to see the applications of the addition and multiplication composition. If G is a finite group, n is a positive integer and a &isins;G, then the order of the products na. When G is a finite group, every element must have finite order. However, the converse is false: there are infinite groups where each element has finite order. For example, in the group of all roots of unity in C<sup>×</sup> each element has finite order. Finally, we find out the order of every element of a group in different types of higher order of group. 展开更多
关键词 order of Element of a group Addition Composition Multiplication Composition Modulo
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Preliminary group classification of quasilinear third-order evolution equations
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作者 黄定江 张鸿庆 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第3期275-292,共18页
Group classification of quasilinear third-order evolution equations is given by using the classical infinitesimal Lie method, the technique of equivalence transformations, and the theory of classification of abstract ... Group classification of quasilinear third-order evolution equations is given by using the classical infinitesimal Lie method, the technique of equivalence transformations, and the theory of classification of abstract low-dimensional Lie algebras. We show that there are three equations admitting simple Lie algebras of dimension three. All non-equivalent equations admitting simple Lie algebras are nothing but these three. Furthermore, we also show that there exist two, five, twenty-nine and twenty-six non- equivalent third-order nonlinear evolution equations admitting one-, two-, three-, and four-dimensional solvable Lie algebras, respectively. 展开更多
关键词 quasilinear third-order evolution equations group classification classical infinitesimal Lie method equivalence transformation group abstract Lie algebras
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Derivation of a second-order model for Reynolds stress using renormalization group analysis and the two-scale expansion technique
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作者 Xiao-Hong Wang Zheng-Feng Liu Xiao-Xia Lu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第5期649-659,共11页
With the two-scale expansion technique proposed by Yoshizawa,the turbulent fluctuating field is expanded around the isotropic field.At a low-order two-scale expansion,applying the mode coupling approximation in the Ya... With the two-scale expansion technique proposed by Yoshizawa,the turbulent fluctuating field is expanded around the isotropic field.At a low-order two-scale expansion,applying the mode coupling approximation in the Yakhot-Orszag renormalization group method to analyze the fluctuating field,the Reynolds-average terms in the Reynolds stress transport equation,such as the convective term,the pressure-gradient-velocity correlation term and the dissipation term,are modeled.Two numerical examples:turbulent flow past a backward-facing step and the fully developed flow in a rotating channel,are presented for testing the efficiency of the proposed second-order model.For these two numerical examples,the proposed model performs as well as the Gibson-Launder (GL) model,giving better prediction than the standard k-ε model,especially in the abilities to calculate the secondary flow in the backward-facing step flow and to capture the asymmetric turbulent structure caused by frame rotation. 展开更多
关键词 Turbulent modeling Renormalization group Two-scale expansion Reynolds stress transport equation Second-order model
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知觉组织对时序知觉的影响:注意线索的作用
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作者 尹天子 刘潇 +2 位作者 刘宗霞 戚江丹 吴倩 《心理科学》 CSCD 北大核心 2024年第1期44-51,共8页
本研究探讨注意线索在知觉组织影响时序知觉中的作用。实验1和实验2采用2(图形朝向:图形对向、图形反向)×2(注意条件:有效线索、无效线索)×9(SOA:0ms、±15ms、±30ms、±45ms、±90ms)的实验设计,分别探讨... 本研究探讨注意线索在知觉组织影响时序知觉中的作用。实验1和实验2采用2(图形朝向:图形对向、图形反向)×2(注意条件:有效线索、无效线索)×9(SOA:0ms、±15ms、±30ms、±45ms、±90ms)的实验设计,分别探讨外源性注意线索、内源性注意线索在知觉组织影响时序知觉中的作用。结果发现,在图形对向和图形反向条件中,被试在有效线索条件比无效线索条件中更倾向于判断注意线索一侧的刺激先出现;但是在有效和无效线索条件中,被试在图形对向条件均比图形反向条件更倾向于判断两个图形同时出现。结果表明,知觉组织对时序知觉的影响受到注意线索的调节,而且外源性和内源性注意线索的作用有差异,但是注意线索不能消除知觉组织对时序知觉的影响。 展开更多
关键词 时序知觉 内源性注意 外源性注意 知觉组织
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智能群体多维感知机器人支持的人机协同研学教学模式--以“孔子”大语言模型会话机器人的研发与教学为例
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作者 李海峰 李广鑫 汤允凤 《现代远距离教育》 2024年第4期48-59,共12页
在大语言模型教育应用中,人机会话反馈形式单一问题一直未得到较好解决,这严重影响了学生的高阶思维能力培养。开发具有智能群体多维感知能力的会话机器人,是解决这一问题的重要途径。为此,研究者以群体感知、同伴反馈和研究性学习理论... 在大语言模型教育应用中,人机会话反馈形式单一问题一直未得到较好解决,这严重影响了学生的高阶思维能力培养。开发具有智能群体多维感知能力的会话机器人,是解决这一问题的重要途径。为此,研究者以群体感知、同伴反馈和研究性学习理论为基础,利用文心一言、飞书开发平台和学习分析等技术,开发了智能群体多维感知会话机器人“孔子”,构建了人机协同研学教学模式。教学实验以“现代教育技术应用”课程为教学内容,采用准实验研究设计,邀请数学专业学生参与实验。结果表明,与直接使用文心一言的教学相比,人机协同研学教学模式能显著提升学生的问题解决能力、批判性思维能力、创新能力和外在学习动机,但对学习绩效、内在动机和协作学习能力效果欠佳。为了提高教学效果,研究者需提高多维感知评价精准性、感知维度全面性、情境学习多样性和教师教学技能。 展开更多
关键词 人机协同研学 生成式人工智能 群体感知 高阶思维 大语言模型
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结构动力问题的高阶精确时步群积分方法
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作者 李鸿晶 杨寅 《振动与冲击》 EI CSCD 北大核心 2024年第12期286-297,共12页
高阶精确时间积分方法可为与时间相关的高频复杂动力行为提供高精度的预测结果,但既有高阶精确时间积分方法普遍存在计算工作量偏大的问题,难以满足实际结构线性和非线性动力分析日益增长的计算需求。该文提出了一种基于时步群的高阶精... 高阶精确时间积分方法可为与时间相关的高频复杂动力行为提供高精度的预测结果,但既有高阶精确时间积分方法普遍存在计算工作量偏大的问题,难以满足实际结构线性和非线性动力分析日益增长的计算需求。该文提出了一种基于时步群的高阶精确时间积分方法,将p(p≥2)个相邻的未知时步组成待求解的时步群,以结构动力方程积分解为基础构建逐时步群求解结构动态响应的时间积分方案。在对每个时步群进行积分的过程中,无需联立求解方程,仅通过矩阵乘法运算即可一次性地计算得到时步群内全部p个时步的动态响应。数值特性分析以及线性与非线性算例试验均表明,该文算法精度高、稳定性好、数值耗散可控,在选择较大的时间步距情形下依然能够稳定地获得高精度的计算结果。相较传统二阶精度时间积分方法,该文算法的计算效率亦有较大幅度地提高。 展开更多
关键词 结构动力分析 高阶精确时间积分 时步群 矩阵指数 微分求积
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基于直觉模糊环境的海上风机选型
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作者 邵萌 毛智谋 +2 位作者 孙金伟 管笑 伊传秀 《科学技术与工程》 北大核心 2024年第16期6649-6658,共10页
选择合适的海上风力发电机机型对海上风电场的长期高效运行起着至关重要的作用。针对决策者在风机选型决策过程中存在不确定性和主观偏好等问题,提出一种改进的多准则决策(multi-criteria decision making, MCDM)框架及方法:在权重求解... 选择合适的海上风力发电机机型对海上风电场的长期高效运行起着至关重要的作用。针对决策者在风机选型决策过程中存在不确定性和主观偏好等问题,提出一种改进的多准则决策(multi-criteria decision making, MCDM)框架及方法:在权重求解算法中将群体决策和直觉模糊数与层次分析法相结合,提出群体直觉模糊层次分析法(group intuitionistic fuzzy analytic hierarchy process, GIAHP)计算指标权重;在备选方案排序算法中将余弦距离引入接近理想点法(technique for order preference by similarity to an ideal solution, TOPSIS),提出多距离TOPSIS确定备选方案排序。最后以山东省海上风电场风机选型为例,并通过敏感性分析验证框架及方法的鲁棒性。该框架及方法为中国海上风电场风机选型提供理论依据,可确保海上风电场长期稳定运行。 展开更多
关键词 海上风机选型 直觉模糊数 群体直觉模糊层次分析法(GIAHP) 多距离接近理想点法(TOPSIS)
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关于一道抽象代数题的推广
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作者 史江涛 王怡然 《高等数学研究》 2024年第4期18-19,共2页
用初等的方法证明了:设G是有限群,p是G的最小素因子,若对任意n∣|G|都有|{x∈G∣x^(n)=1}|≤(p-1)n,则G是循环群.推广了教材[1]第1.4节的习题3.
关键词 有限群 最小素因子 素数幂阶子群 正规 循环群
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Step‑by‑Step Modulation of Crystalline Features and Exciton Kinetics for 19.2%Efficiency Ortho‑Xylene Processed Organic Solar Cells 被引量:1
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作者 Bosen Zou Weiwei Wu +10 位作者 Top Archie Dela Pena Ruijie Ma Yongmin Luo Yulong Hai Xiyun Xie Mingjie Li Zhenghui Luo Jiaying Wu Chuluo Yang Gang Li He Yan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期258-272,共15页
With plenty of popular and effective ternary organic solar cells(OSCs)construction strategies proposed and applied,its power conversion efficiencies(PCEs)have come to a new level of over 19%in single-junction devices.... With plenty of popular and effective ternary organic solar cells(OSCs)construction strategies proposed and applied,its power conversion efficiencies(PCEs)have come to a new level of over 19%in single-junction devices.However,previous studies are heavily based in chloroform(CF)leaving behind substantial knowledge deficiencies in understanding the influence of solvent choice when introducing a third component.Herein,we present a case where a newly designed asymmetric small molecular acceptor using fluoro-methoxylated end-group modification strategy,named BTP-BO-3FO with enlarged bandgap,brings different morphological evolution and performance improvement effect on host system PM6:BTP-eC9,processed by CF and ortho-xylene(o-XY).With detailed analyses supported by a series of experiments,the best PCE of 19.24%for green solvent-processed OSCs is found to be a fruit of finely tuned crystalline ordering and general aggregation motif,which furthermore nourishes a favorable charge generation and recombination behavior.Likewise,over 19%PCE can be achieved by replacing spin-coating with blade coating for active layer deposition.This work focuses on understanding the commonly met yet frequently ignored issues when building ternary blends to demonstrate cutting-edge device performance,hence,will be instructive to other ternary OSC works in the future. 展开更多
关键词 Organic solar cells Ternary design Solvent selection Flouro-methoxylated end group Morphological ordering
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