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Science China Chemistry 2023年第8期66卷 2238-2255页

作者： Xi Wang youbin peng Ling Zhao Xiaohong Huo Wanbin Zhang Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai200240China

In contrast to the stereocontrol of the stereocenter at the allyl unit,the asymmetric induction of prochiral nucleophiles remains a challenge in Pd-catalyzed asymmetric allylic substitutions due to the remote distance between the chiral catalyst and the stereocenter established at prochiral *** effort has been devoted to solving this challenge through the elaborate design of chiral ***,synergistic catalysis has gained increasing attention owing to its potential advantages over the traditional single palladium catalysis,such as improvement of reactivity and *** strategy,including bimetallic catalysis and Pd/organocatalysis,not only broadens the scope of prochiral nucleophiles,but also provides a simple and unified method for the stereocontrol of prochiral *** review summarizes the brief history and advances in this field.

关键词： asymmetric allylic substitution palladium catalysis synergistic catalysis remote stereocontrol bimetallic catalysis

Base-Promoted Coupling of Carbon Dioxide,Amines and Diaryliodonium Salts:A Phosgene-Free Route to Arvl Carbamates

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Base-Promoted Coupling of Carbon Dioxide,Amines and Diarylio...

秋怀壮士墓碑前,一战风云越百年--记ACPB会员凭吊华工纪念群雕

中国化学会全国第十二届有机合成化学学术研讨会

作者： Wenfang Xiong Chaorong Qi youbin peng Tianzuo Guo Min Zhang Huanfeng Jiang School of Chemistry and Chemical Engineering South China University of Technology

The conversion of carbon dioxide(CO

关键词： Diaryliodonium Salts Carbon Dioxide Aryl Carbamates

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雕塑 2018年第6期 86-87页

作者：彭友彬旅比华人专业人士协会acpb

在欧洲,每年的11月11日是纪念一战停战的日子。在比利时北部的波普林格(Popennge),2017年还专门为在那里牺牲的华工们修建了一座群雕。今年适逢“一战”停战一百周年,因华工多为山东人,山东省侨办组团到比利时来凭吊先辈,特邀在比华人... 详细信息

在欧洲,每年的11月11日是纪念一战停战的日子。在比利时北部的波普林格(Popennge),2017年还专门为在那里牺牲的华工们修建了一座群雕。今年适逢“一战”停战一百周年,因华工多为山东人,山东省侨办组团到比利时来凭吊先辈,特邀在比华人到场支持,我便和ACPB的朋友一起驾车前往。

关键词：华工群雕纪念墓碑会员比利时山东人山东省

经尿道前列腺剜除电切术与传统经尿道前列腺电切术治疗大体积前列腺增生效果比较

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中外医学研究 2019年第29期17卷 45-47页

作者：彭友彬汕头大学医学院第二附属医院

目的:探析大体积前列腺增生予以传统经尿道前列腺电切术(TURP)和经尿道前列腺剜除电切术治疗的临床效果。方法:临床选择2017年5月-2018年3月在笔者所在医院就诊的大体积前列腺增生患者90例,根据随机对照法分为研究组(n=46)与对照组(n=4... 详细信息

目的:探析大体积前列腺增生予以传统经尿道前列腺电切术(TURP)和经尿道前列腺剜除电切术治疗的临床效果。方法:临床选择2017年5月-2018年3月在笔者所在医院就诊的大体积前列腺增生患者90例,根据随机对照法分为研究组(n=46)与对照组(n=44),研究组予以经尿道前列腺剜除电切术,对照组予以传统经尿道前列腺电切术(TURP)治疗。比较两组尿管留置时间、冲洗膀胱时间、术中出血量、前列腺切除量、住院时间等指标变化;治疗后1个月比较两组术后国际前列腺症状评分(IPSS)、残留尿量、最大尿流率等指标变化;比较两组术后并发症。结果:研究组尿管留置时间、冲洗膀胱时间、术中出血量、住院时间均低于对照组,前列腺切除量高于对照组,差异均有统计学意义(P<0.05);研究组术后1个月IPSS评分、残留尿量均低于对照组,最大尿流率高于对照组,差异均有统计学意义(P<0.05);研究组排尿困难、膀胱痉挛、尿失禁等并发症总发生率低于对照组,差异有统计学意义(P<0.05)。结论:大体积前列腺增生经尿道前列腺剜除术治疗,术中出血量低,缩短住院时间、尿管留置时间、冲洗膀胱时间,显著改善临床症状,术后并发症少。

关键词：大体积前列腺增生并发症 TURP 等离子前列腺剜除术

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柴北缘下奥陶统烃源岩有机地球化学特征

天然气工业 2004年第4期24卷 7-9,T001页

作者：文志刚王正允何幼斌彭德堂长江大学地球化学研究中心

柴北缘下奥陶统多泉山组发育暗色碳酸盐岩 ,石灰沟组发育暗色泥岩 ;从实测的残余有机碳、生烃潜量与理论上恢复后的原始有机碳、生烃潜量来看 ,研究区暗色碳酸盐岩为非烃源岩 ,而暗色泥岩则为较好—好的烃源岩。沥青反射率及储层的包裹... 详细信息

柴北缘下奥陶统多泉山组发育暗色碳酸盐岩 ,石灰沟组发育暗色泥岩 ;从实测的残余有机碳、生烃潜量与理论上恢复后的原始有机碳、生烃潜量来看 ,研究区暗色碳酸盐岩为非烃源岩 ,而暗色泥岩则为较好—好的烃源岩。沥青反射率及储层的包裹体均一化温度显示 :下奥陶统烃源岩有机质演化处于高成熟阶段。生烃史分析表明 ,烃源岩中有机质在奥陶纪末期—志留纪早期曾有一次短暂的成烃期 ,在二叠纪末—三叠纪进入生油主期 ,到白垩纪进入高成熟阶段 ;包裹体均一化温度反映油气成藏期位于中生代晚期—新生代。

关键词：有机地球化学柴达木盆地下奥陶统烃源岩油气藏

Time-Periodic Solutions to Quasilinear Hyperbolic Systems on General Networks

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Chinese Annals of Mathematics,Series B 2024年第1期45卷 41-72页

作者： peng QU School of Mathematical Sciences Fudan UniversityShanghai 200433China

For quasilinear hyperbolic systems on general networks with time-periodic boundary-interface conditions with a dissipative structure,the existence and stability of the time-periodic classical solutions are discussed.

关键词： Time-periodic solution Quasilinear hyperbolic system General net-work Classical solution Asymptotic stability

Thermal and mechanical behavior of casting copper alloy wheel during wheel and belt continuous casting process

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China Foundry 2024年第1期21卷 82-90页

作者： Kun Gao Yan peng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

To investigate the thermal and mechanical behavior of casting wheel,a two-dimensional thermoelastic-plastic finite element model was used to predict the temperature,stress and distortion distribution of the casting wheel during the wheel and belt continuous casting *** effects of grinding thickness and casting speed on the thermal and mechanical behaviors of the center of the hot face of the casting wheel were discussed in *** each rotation,the casting wheel passes through four different spray *** results show that the temperature distribution of the casting wheel in different spray zones is similar,the temperature of the hot face is the highest and the temperature reaches the peak in the spray zoneⅢ.The stress and distortion depend on the temperature distribution,and the maximum stress and distortion of the hot face are 358.2 MPa and 1.82 mm,*** temperature at the center of the hot face decreases with increasing grinding thickness and increases with increasing casting speed.

关键词： casting wheel finite element model grinding thickness casting speed hot face spray zones

Numerical simulation of fluid flow and free surface fluctuations during wheel and belt casting process

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Journal of Iron and Steel Research International 2024年第5期31卷 1117-1126页

作者： Kun Gao Yan peng National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina

The unstable fluid flow and severe free surface fluctuations in the wheel and belt caster can affect the quality of the cast *** lower level height tends to entrap inclusions in the molten *** the other hand,the higher level height makes the production process more dangerous due to the overflow of high temperature fluid from the mold.A computational model of the molten metal pouring process was *** transient fluid flow and free surface fluctuations behavior were calculated using the three-dimensional large eddy simulation model and the volume of fluid *** results show that the flow velocity of the main jet gradually decreases under the influence of the low kinetic energy fluid in the *** is an obvious oscillation in the tail of the jet,while the flow field is asymmetric in *** jet is closer to the inside radius side due to the Coanda effect,and there is a recirculation zone on the inside radius and the outside radius respectively,according to the 10 s time-averaged *** with the industrial observation and simulation results,the shape of the free surface is a wave that varies with *** addition,the free surface height is lowest and the flow velocity is highest in the region near the jet.

关键词： Fluid flow Free surface Wheel and belt caster Large eddy simulation Volume of fluid method

Two-Stage Online Debiased Lasso Estimation and Inference for High-Dimensional Quantile Regression with Streaming Data

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Journal of Systems Science & Complexity 2024年第3期37卷 1251-1270页

作者： peng Yanjin WANG Lei School of Statistics and Data Science KLMDASRLEBPS and LPMCNankai UniversityTianjin 300071China

In this paper,the authors propose a two-stage online debiased lasso estimation and statistical inference method for high-dimensional quantile regression(QR)models in the presence of streaming *** the first stage,the authors modify the QR score function based on kernel smoothing and obtain the online lasso smoothed QR estimator through iterative *** estimation process only involves the current data batch and specific historical summary statistics,which perfectly accommodates to the special structure of streaming *** the second stage,an online debiasing procedure is carried out to eliminate biases caused by the lasso penalty as well as the accumulative approximation error so that the asymptotic normality of the resulting estimator can be *** authors conduct extensive numerical experiments to evaluate the performance of the proposed *** experiments demonstrate the effectiveness of the proposed method and support the theoretical *** application to the Beijing PM2.5 Dataset is also presented.

关键词： Adaptive tuning asymptotic normality debiased lasso online updating quantile regres-sion

Electronic origin of structural degradation in Li-rich transition metal oxides:The case of Li_(2)MnO_(3)and Li_(2)RuO_(3)

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Journal of Semiconductors 2024年第4期45卷 82-86页

作者： peng Zhang Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics andOp toelec-tronic EngineeringShenzhen UniversityShenzhen 518060China

Li_(2)MnO_(3)and Li_(2)RuO_(3)represent two prototype Li-rich transition metal(TM)oxides as high-capacity cathodes for Li-ion batteries,which have similar crystal structures but show quite different cycling ***,based on the first-princi-ples calculations,we systematically studied the electronic structures and defect properties of these two Li-rich cathodes,in order to get more understanding on the structural degradation mechanism in Li-rich TM *** calculations indicated that the structural and cycling stability of Li_(2)MnO_(3)and Li_(2)RuO_(3)depend closely on their electronic structures,especially the energy of their highest occupied electronic states(HOS),as it largely determines the defect properties of these *** Li_(2)MnO_(3)with low-energy HOS,we found that,due to the defect charge transfer mechanism,various defects can form spontaneously in its host structure as Li ions are extracted upon delithiation,which seriously deteriorates its structural and cycling *** for Li_(2)RuO_(3),on the other hand,we identified that the high-energy HOS prevents it from the defect formation upon delithi-ation and thus preserve its cycling *** studies thus illustrated an electronic origin of the structural degradation in Li-rich TM oxides and implied that it is possible to improve their cycling performances by carefully adjusting their TM compo-nents.

关键词： defects Li-ion batteries first-principles calculations