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Some Reciprocity Formulas for Generalized Dedekind-Rademacher Sums
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作者 HE Yuan SHI Yongguo 《数学进展》 北大核心 2026年第1期85-102,共18页
In this paper,we study the generalized Dedekind Rademacher sums considered by Hall,Wilson and Zagier.We establish a new formula for the products of two Bernoulli functions by using Parseval's formula,Hurwitz's... In this paper,we study the generalized Dedekind Rademacher sums considered by Hall,Wilson and Zagier.We establish a new formula for the products of two Bernoulli functions by using Parseval's formula,Hurwitz's formula and Lerch's functional equation.As applications of the result,some well-known reciprocity formulas are deduced as special cases. 展开更多
关键词 Bernoulli function Dedekind sum Hurwitz and Lerch zeta function reciprocity formula
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Robust and Readily Functionalized Microcapsules from Interfacial Click Polymerization of Amphiphilic Alternating Copolymers
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作者 Qing-Song Xu Min-Jiang Zhu +4 位作者 Xiu-Ting Li Jie Dong Xin Zhao Qing-Hua Zhang Yong-Feng Zhou 《Chinese Journal of Polymer Science》 2026年第2期389-397,I0010,共10页
The preparation and functionalization of polymeric capsules attract intense attention due to their application in various areas.Herein we presented an amphiphilic alternating copolymer(ACP)-based microcapsule which is... The preparation and functionalization of polymeric capsules attract intense attention due to their application in various areas.Herein we presented an amphiphilic alternating copolymer(ACP)-based microcapsule which is both robust and readily-functionalized through interfacial click polymerization.A water-in-oil emulsion was constructed to act as the reaction medium,the hydrophilic 1,3-butadiene diepoxide(BDE)in water phase reacted with the oleophilic 1,4-dibutanedithiol(BDT)in oil phase at the water-oil interface to form the amphiphilic ACP named poly(2,3-dihydroxy butylene-alt-butylene dithioether)(abbreviated as P(DHB-a-BDT)below),which would deposite in situ to form the micro-sized capsules.Significantly,the dried capsules are robust enough to be rehydrated once the water was added and almost restored their original morphologies.Further elucidation showed that the Young's modulus of these capsules exceeded 1 GPa.As long as we know,it is the first time for the mechanical properties of the ACP-based microstructures being investigated.Besides,functionalization could be achieved simultaneously with the formation process.As a proof of concept,positive-charged capsules were successfully obtained through click copolymerization.Stemming from the unique characteristics of amphiphilic ACPs which combined both merits of click chemistry and interfacial reactions,all these features of the current method as well as the resultant capsules may promote the application of the polymeric capsules. 展开更多
关键词 Click chemistry Interfacial reaction Amphiphilic alternating copolymer MICROCAPSULE Young's modulus
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2010—2023年北京市西城区猩红热流行病学特征及CUSUM模型的预警分析
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作者 秦迪 魏孝侃 +5 位作者 马春娜 管秀刚 陈瑜 孙景異 肖征 初艳慧 《预防医学情报杂志》 2025年第6期746-752,共7页
目的 分析2010—2023年北京市西城区猩红热的流行特征,并结合累积和(CUSUM)模型进行预警分析,为制定有针对性的防控措施提供科学依据。方法 应用描述性流行病学方法对2010—2023年北京市西城区猩红热病例进行分析,使用SPSS 25.0软件进... 目的 分析2010—2023年北京市西城区猩红热的流行特征,并结合累积和(CUSUM)模型进行预警分析,为制定有针对性的防控措施提供科学依据。方法 应用描述性流行病学方法对2010—2023年北京市西城区猩红热病例进行分析,使用SPSS 25.0软件进行数据整理分析,率的比较采用χ^(2)检验,R 4.3.3软件绘制发病率分布热图,应用CUSUM模型探测猩红热流行的起始时间,检验水准α=0.05。结果 2010—2023年,北京市西城区共报告猩红热病例3 328例,年均发病率为18.84/10万,不同年份发病率差异有统计学意义(χ^(2)=1 450.543,P<0.001;χ_(趋势)^(2)=238.637,P<0.001)。2011年报告病例数及发病率最高(504例,40.54/10万);2014年和2017—2018年分别出现2次反弹,发病率分别为30.62/10万、32.09/10万和33.03/10万;2020—2022年为低发年,年均发病率为1.85/10万,较2010—2019年下降了92.35%。猩红热发病具有显著的季节性,4至6月和11月至次年1月为发病高峰期,2020—2023年流行高峰并不明显,流行起始时间最早为每年的第11周和第39周,不同月份发病率差异有统计学意义(χ^(2)=1 260.787,P<0.001)。男性年均发病率高于女性(χ^(2)=228.578,P<0.001)。3~9岁发病人数最多,3岁~组和6岁~组发病率较高,不同年龄组发病率差异有统计学意义(χ^(2)=37 869.544,P<0.001)。病例以学生(70.43%)和幼托儿童(27.46%)为主。年均报告病例数和年均发病率最高的3个街道分别为展览路、新街口和德胜街道,月均发病率最高的为展览路街道5月发病率,各地区发病率差异有统计学意义(χ^(2)=315.562,P<0.001)。结论 2010—2023年北京市西城区猩红热发病率整体呈波动下降趋势,流行的起始时间在每年的3月和10月,3~9岁年龄组的小学生及幼托儿童为主要发病人群。流行前期应做好预测预警,加强对小学及托幼机构等重点场所和重点区域的监测与报告,严格落实各项防控措施,防止疫情出现反弹。 展开更多
关键词 猩红热 A组链球菌 流行病学特征 累积和模型
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Some Properties on the Error-Sum Function of Alternating Sylvester Series 被引量:1
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作者 Huiping Jing Luming Shen 《Advances in Pure Mathematics》 2012年第6期459-463,共5页
The error-sum function of alternating Sylvester series is introduced. Some elementary properties of this function are studied. Also, the hausdorff dimension of the graph of such function is determined.
关键词 alternating SYLVESTER SERIES Error-sum Function HAUSDORFF Dimension
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Generalizations of Some Formulas of the Reciprocal Sum and Alternating Sum for Generalized Lucas Numbers
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作者 YE Xiao-li LIU Mai-xue 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期99-103,共5页
The purpose of this article is to provide the inversion relationships between the reciprocal sum S(1, 2,…, m) and the alternating sum T(1, 2,…, m) for generalized Lucas numbers which generalizes the Melham's re... The purpose of this article is to provide the inversion relationships between the reciprocal sum S(1, 2,…, m) and the alternating sum T(1, 2,…, m) for generalized Lucas numbers which generalizes the Melham's results. 展开更多
关键词 generalized Lucas numbers reciprocal sum alternating sum
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基于CUSUM方法的胚胎冻融技术专科培训过程动态分析:存活率与操作时间的双维度评价
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作者 竺海燕 赵晨琼 《全科医学临床与教育》 2025年第11期1007-1009,1024,F0002,F0003,共6页
目的分析胚胎实验室技术员通过个体化胚胎冻融技术培训的累积和学习曲线(CUSUM),探讨专科技术员达到技术熟练程度的时间及随着时间推移保持胚胎冻融技术的熟练程度。方法选取2017年7月至2024年6月以来入职浙江大学医学院附属邵逸夫医院... 目的分析胚胎实验室技术员通过个体化胚胎冻融技术培训的累积和学习曲线(CUSUM),探讨专科技术员达到技术熟练程度的时间及随着时间推移保持胚胎冻融技术的熟练程度。方法选取2017年7月至2024年6月以来入职浙江大学医学院附属邵逸夫医院生殖中心的胚胎实验室初级专科技术学员共10名,采用CUSUM分析方法,对10名专科技术学员在25 d训练周期内的胚胎冷冻复苏存活率与操作时间两项关键指标进行动态监测。结果学员操作时间CUSUM图分为三个显著阶段:初始下降阶段(1~8 d)、加速下降阶段(9~17 d)及稳定下降阶段(18~25 d)。存活率CUSUM曲线形态分析显示三个关键阶段:快速下降期(1~10 d)、减缓下降期(11~17 d)及稳定期(18~25 d)。进入稳定维持阶段,各学员胚胎冷冻复苏存活率CUSUM曲线终值分布在-160~-215之间,差异相对操作时间CUSUM曲线较小。结论CUSUM方法对胚胎冷冻操作时间及胚胎冷冻复苏存活率进行双维度动态分析,为优化胚胎技术员培训设计、提升教学效能提供了实证依据。 展开更多
关键词 累积和学习曲线 辅助生殖技术 专科技术员 胚胎冻融技术
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Some Alternating Double Binomial Sums
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作者 ZHENG De-yin TANG Pei-pei 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第4期573-577,共5页
We consider some new alternating double binomial sums. By using the Lagrange inversion formula, we obtain explicit expressions of the desired results which are related to a third-order linear recursive sequence. Furth... We consider some new alternating double binomial sums. By using the Lagrange inversion formula, we obtain explicit expressions of the desired results which are related to a third-order linear recursive sequence. Furthermore, their recursive relation and generating functions are obtained. 展开更多
关键词 alternating double binomial sum Lagrange inversion formula Fibonacci num-ber
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Super Congruences Involving Alternating Harmonic Sums
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作者 Zhongyan Shen Tianxin Cai 《Advances in Pure Mathematics》 2020年第10期611-622,共12页
Let p be an odd prime, the harmonic congruence such as <img alt="" src="Edit_843b278d-d88a-45d3-a136-c30e6becf142.bmp" />, and many different variations and generalizations have been studied ... Let p be an odd prime, the harmonic congruence such as <img alt="" src="Edit_843b278d-d88a-45d3-a136-c30e6becf142.bmp" />, and many different variations and generalizations have been studied intensively. In this note, we consider the congruences involving the combination of alternating harmonic sums, <img alt="" src="Edit_e97d0c64-3683-4a75-9d26-4b371c2be41e.bmp" /> where P<sub>P </sub>denotes the set of positive integers which are prime to p. And we establish the combinational congruences involving alternating harmonic sums for positive integer n=3,4,5. 展开更多
关键词 Bernoulli Numbers alternating Harmonic sums CONGRUENCES Modulo Prime Powers
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ON THE ERROR-SUM FUNCTION OF ALTERNATING LüROTH SERIES
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作者 Luming Shen Chao Ma Jihong Zhang 《Analysis in Theory and Applications》 2006年第3期223-232,共10页
The error-sum function of alternating Lǖroth series is introduced, which, to some extent, discerns the superior or not of an expansion comparing to other expansions. Some elementary properties of this function are st... The error-sum function of alternating Lǖroth series is introduced, which, to some extent, discerns the superior or not of an expansion comparing to other expansions. Some elementary properties of this function are studied. Also, the Hausdorff dimension of graph of such function is determined. 展开更多
关键词 alternating Lǖroth series error-sum function Hausdorff dimension
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A Verification Theorem for Feedback Nash Equilibrium in Multiple-Player Nonzero-Sum Impulse Game 被引量:1
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作者 Ruihai Li Yaoyao Tan +1 位作者 Xiaojie Su Jiangshuai Huang 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期648-650,共3页
Dear Editor,This letter addresses the impulse game problem for a general scope of deterministic,multi-player,nonzero-sum differential games wherein all participants adopt impulse controls.Our objective is to formulate... Dear Editor,This letter addresses the impulse game problem for a general scope of deterministic,multi-player,nonzero-sum differential games wherein all participants adopt impulse controls.Our objective is to formulate this impulse game problem with the modified objective function including interaction costs among the players in a discontinuous fashion,and subsequently,to derive a verification theorem for identifying the feedback Nash equilibrium strategy. 展开更多
关键词 impulse game feedback Nash equilibrium multiple player feedback nash equilibrium strategy impulse game problem nonzero sum modified objective function impulse controlsour
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On the Triple Sums of Hecke Eigenvalues on Certain Polynomials
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作者 HUA Guodong 《数学进展》 北大核心 2025年第6期1261-1277,共17页
Let f,g and h be three distinct primitive holomorphic cusp forms of even integral weights k_(1),k_(2)and k_(3)for the full modular groupΓ=SL(2,Z),and denote byλ_(f)(n),λ_(g)(n),λ_(h)(n)the corresponding normalized... Let f,g and h be three distinct primitive holomorphic cusp forms of even integral weights k_(1),k_(2)and k_(3)for the full modular groupΓ=SL(2,Z),and denote byλ_(f)(n),λ_(g)(n),λ_(h)(n)the corresponding normalized Fourier coefficients,respectively.In this paper,we investigate the correlations of triple sums associated to these Fourier coefficientsλ_(f)(n),λ_(g)(n),λ_(h)(n)over certain polynomials,and obtain some power-saving asymptotic estimates which beat the trivial bounds. 展开更多
关键词 Hecke eigenvalue triple correlation sum automorphic L-function asymptotic behavior
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The strongest early-summer drought–flood abrupt alternation event over the Huang–Huai–Hai River Basin in 2024 since the 1980s:Perspective of anomalous subseasonal circulation evolution 被引量:1
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作者 Zhiheng Chen Zhihai Zheng 《Atmospheric and Oceanic Science Letters》 2025年第5期65-72,共8页
Since the 21st century,the Huang–Huai–Hai River Basin(HHHRB)in China has experienced increased frequency and severity of drought–flood abrupt alternation(DFAA)events during early summer,characterized by droughts in... Since the 21st century,the Huang–Huai–Hai River Basin(HHHRB)in China has experienced increased frequency and severity of drought–flood abrupt alternation(DFAA)events during early summer,characterized by droughts in June followed by floods in July.The 2024 event was the most severe since 1981.This study demonstrates that such compound extreme events are closely linked to anomalous subseasonal evolution of large-scale atmospheric circulation.During the drought phase,the East Asian subtropical westerly jet(EAJ)shifts southward,and the western Pacific subtropical high(WPSH)exhibits anomalous strengthening with its western ridge line displaced southward.The flood phase is characterized by acceleration of the EAJ,westward extension of the WPSH,and enhanced southwestern moisture transport from the western Pacific.Beyond these typical features,the 2024 early summer circulation exhibited unique characteristics:Anomalous northeastward intensification of the WPSH facilitated merged moisture influx from both the Indian Ocean and the western Pacific along the southeast pathway into the HHHRB in July,resulting in the highest net moisture inflow at the southern boundary of the HHHRB since 1981.The synergistic effects of multiple factors primarily explain the exceptionally intense DFAA event in 2024. 展开更多
关键词 Drought-flood abrupt alternation Anomalous subseasonal circulation evolution East Asian subtropical westerly jet Western Pacific subtropical high Water vapor transportation
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基于Summing Mixer的小型录音棚录音系统设计与实现——某研究院声像中心录音棚建设实例
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作者 刘牧 苑方磊 +1 位作者 宋华华 李杰 《电声技术》 2025年第1期20-25,共6页
小型录音棚通常具有空间小、投资省、设备系统简约以及使用灵活高效等特点。通过设计一个小型录音棚录音系统,提出以Summing Mixer为路由与控制核心的系统整体设计方案,包括拾音系统、数字音频系统、监听系统以及硬件效果器系统等分系... 小型录音棚通常具有空间小、投资省、设备系统简约以及使用灵活高效等特点。通过设计一个小型录音棚录音系统,提出以Summing Mixer为路由与控制核心的系统整体设计方案,包括拾音系统、数字音频系统、监听系统以及硬件效果器系统等分系统设计。通过配备硬件压缩器、限制器、均衡器以及混响器等设备,为小型数字录音系统添加了“模拟味”。最后,探讨了设计系统在录音实践中实现零延迟返送监听、外部设备多链路接入、母带制作路由等技术优势。 展开更多
关键词 录音 小型录音棚 summing Mixer 系统设计
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三类基于Weil sums的线性码
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作者 廖崟琎 何佳维 《南昌航空大学学报(自然科学版)》 2025年第2期35-42,共8页
近年来,少重量线性码被广泛地研究。少重量线性码在强正则图、密钥分享方案、关联方案以及认证码等领域均有应用。本文选取特定定义集,进而构造出有限域上的三类6-重量线性码,并借助Weil sums确定这三类线性码的重量分布情况。
关键词 线性码 重量分布 Weil sums
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Equivalent Conditions of Complete Convergence for Weighted Sums of Sequences of i.i.d.Random Variables under Sublinear Expectations
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作者 XU Mingzhou CHENG Kun 《应用概率统计》 北大核心 2025年第3期339-352,共14页
The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the... The complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space is studied.By moment inequality and truncation methods,we establish the equivalent conditions of complete convergence for weighted sums of sequences of independent,identically distributed random variables under sublinear expectation space.The results complement the corresponding results in probability space to those for sequences of independent,identically distributed random variables under sublinear expectation space. 展开更多
关键词 complete convergence weighted sums i.i.d.random variables sublinear expectation
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Complete f-Moment Convergence for Sung’s Type Weighted Sums of Negatively Superadditive Dependent Random Variables
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作者 HU Xueping WANG Liuliu +1 位作者 HU Ke XU Zhonghao 《应用概率统计》 北大核心 2025年第4期585-601,共17页
In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergen... In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergence of NSD random variables.We establish and improve a general result on the complete f-moment convergence for Sung’s type randomly weighted sums of NSD random variables under some general assumptions.As an application,we show the complete consistency for the randomly weighted estimator in a nonparametric regression model based on NSD errors. 展开更多
关键词 Marcinkiewicz-Zygmund inequality Rosenthal-type inequality Sung’s type randomly weighted sums negatively superadditive dependent random variables complete f-moment convergence
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Infrared small target detection algorithm via partial sum of the tensor nuclear norm and direction residual weighting
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作者 SUN Bin XIA Xing-Ling +1 位作者 FU Rong-Guo SHI Liang 《红外与毫米波学报》 北大核心 2025年第2期277-288,共12页
Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small targe... Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small target detection method based on the tensor nuclear norm and direction residual weighting was proposed.Based on converting the infrared image into an infrared patch tensor model,from the perspective of the low-rank nature of the background tensor,and taking advantage of the difference in contrast between the background and the target in different directions,we designed a double-neighborhood local contrast based on direction residual weighting method(DNLCDRW)combined with the partial sum of tensor nuclear norm(PSTNN)to achieve effective background suppression and recovery of infrared small targets.Experiments show that the algorithm is effective in suppressing the background and improving the detection ability of the target. 展开更多
关键词 infrared small target detection infrared patch tensor model partial sum of the tensor nuclear norm direction residual weighting
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Improved Sensitivity Encoding Parallel Magnetic Resonance Imaging Reconstruction Algorithm Based on Efficient Sum of Outer Products Dictionary Learning
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作者 DUAN Jizhong SU Yan 《Journal of Shanghai Jiaotong university(Science)》 2025年第3期561-571,共11页
Sensitivity encoding(SENSE)is a parallel magnetic resonance imaging(MRI)reconstruction model by utilizing the sensitivity information of receiver coils to achieve image reconstruction.The existing SENSE-based reconstr... Sensitivity encoding(SENSE)is a parallel magnetic resonance imaging(MRI)reconstruction model by utilizing the sensitivity information of receiver coils to achieve image reconstruction.The existing SENSE-based reconstruction algorithms usually used nonadaptive sparsifying transforms,resulting in a limited reconstruction accuracy.Therefore,we proposed a new model for accurate parallel MRI reconstruction by combining the L0 norm regularization term based on the efficient sum of outer products dictionary learning(SOUPDIL)with the SENSE model,called SOUPDIL-SENSE.The SOUPDIL-SENSE model is mainly solved by utilizing the variable splitting and alternating direction method of multipliers techniques.The experimental results on four human datasets show that the proposed algorithm effectively promotes the image sparsity,eliminates the noise and artifacts of the reconstructed images,and improves the reconstruction accuracy. 展开更多
关键词 parallel magnetic resonance imaging(MRI) sensitivity encoding(SENSE) efficient sum of outer products dictionary learning(SOUPDIL) alternating direction method of multipliers
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Alternating Copolymerization of Dihydrocoumarin and Epoxides Catalyzed by 1-Ethyl-3-methylimidazolium Chloride
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作者 Jing-Jing Yu Yong-Li Li +4 位作者 Xue Wu Zhi-Dong Li Ye-Fan Liu Yang Zhang Peng-Fei Song 《Chinese Journal of Polymer Science》 2025年第8期1269-1276,共8页
The ring-opening alternating copolymerization(ROAC)of 3,4-dihydrocoumarin(DHC)/epoxides has been successfully developed using an imidazolium salt of 1-ethyl-3-methylimidazolium chloride(EMIMCl)as a catalyst.The result... The ring-opening alternating copolymerization(ROAC)of 3,4-dihydrocoumarin(DHC)/epoxides has been successfully developed using an imidazolium salt of 1-ethyl-3-methylimidazolium chloride(EMIMCl)as a catalyst.The resulting copolymer has a molecular weight of 13.7kg·mol^(-1),a narrow molecular weight distribution of 1.03 and a strictly alternating structure.The MALDI-TOF MS characterization and DFT calculations including electrostatic potential(ESP),hydrogen-atom abstraction(HAA),independent gradient model based on hirshfeld partition(IGMH)and atoms-in-molecules(AIM)analysis were used to investigate the metal-free catalytic process.The synergistic effect of anions and cations of EMIMCl for ROAC of DHC and epoxides was demonstrated.This study provides a metal-free catalytic system for the facile synthesis of alternating polyesters from DHC. 展开更多
关键词 alternating copolymerization Dihydrocoumarin EPOXIDES Imidazolium salt Metal-free catalysis
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Modification of texture in AZ31 magnesium alloy via cold pre-upsetting alternating forward extrusion
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作者 Shun Luo Feng Li +2 位作者 Yuan Qi Li Hai Bo Wang Jia Yang Zhang 《Journal of Magnesium and Alloys》 2025年第12期6183-6194,共12页
Prefabricated twinning represents an effective strategy for optimizing the microstructure of extruded forming components and facilitating changes in texture.The study examines the incorporation of[10-12]twins into an ... Prefabricated twinning represents an effective strategy for optimizing the microstructure of extruded forming components and facilitating changes in texture.The study examines the incorporation of[10-12]twins into an AZ31 magnesium alloy billet via cold pre-upsetting deformation before alternating forward extrusion(CUAFE).The experimental results indicate that the initial presence of[10-12]twins is advantageous for the development of[10-10]and[11-20]texture components during the extrusion process.In addition,different DRX mechanisms have different influences on the evolution of basal texture.The CDRX grains tend to preferentially select the[11-20]texture orientation,weakening the[10-10]texture and enhancing the[11-20]texture.However,most DDRX grains deviate significantly from the orientation of their surrounding original grain and do not have a preferred orientation.This is reflected in the mechanical properties of the CUAFE part.The tensile strength is 323.5 MPa,while the elongation is as high as 20.1%. 展开更多
关键词 alternating forward extrusion Pre-upsetting TWINNING RECRYSTALLIZATION TEXTURE
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