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异文形态与择调观念:《玉京秋》清代接受考论
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作者 沙先一 《中山大学学报(社会科学版)》 CSSCI 北大核心 2024年第4期52-61,共10页
《玉京秋》为宋末周密的自创调,由于周密词集版本较多以及清代词选、词律、词谱中的《玉京秋》多有异文,以至于清人所填《玉京秋》多有不同,并且发生争议。这一历史过程,涉及周密词集在明清时期的传播、相关词选与律谱间的交互影响、清... 《玉京秋》为宋末周密的自创调,由于周密词集版本较多以及清代词选、词律、词谱中的《玉京秋》多有异文,以至于清人所填《玉京秋》多有不同,并且发生争议。这一历史过程,涉及周密词集在明清时期的传播、相关词选与律谱间的交互影响、清人填词创作时的文本依据等诸多问题,而不同文献所载《玉京秋》之间的异文、清人创作《玉京秋》时的不同体制以及对待《词律》与《钦定词谱》、《草窗词》与《蘋洲渔笛谱》的不同态度、不同选择,也为考察清人的填词过程、词体观念以及《玉京秋》的经典化过程提供了很好的观察视角。 展开更多
关键词 《玉京秋》 异文形态 择调观念 经典化
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小晏词的用调 被引量:2
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作者 陈振寰 《国际安全研究》 CSSCI 1997年第3期24-31,共8页
晏几道择用词调特重音乐性,特重演唱,故作品以令词为主体(占85%),极少用长调(仅三调四曲),其择用旧曲,亦特重流传久远、音律谐美、最为乐工歌伎所熟悉者。这固然与词调的发展过程有一定关系,但归根结蒂还是词的内容、小晏... 晏几道择用词调特重音乐性,特重演唱,故作品以令词为主体(占85%),极少用长调(仅三调四曲),其择用旧曲,亦特重流传久远、音律谐美、最为乐工歌伎所熟悉者。这固然与词调的发展过程有一定关系,但归根结蒂还是词的内容、小晏的性格特点及其美学趣味所决定的。小晏所用词调中,自创、始用、改用者达47%。自制诸调,音律和谐、四声考究;改制诸调,后多被《词律》定为正格。据此可以推知,小晏不单是北宋词史上有影响的词家。 展开更多
关键词 择调 音乐家 晏几道词
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Enhanced selectivity of catalytic hydrogenation of halogenated nitroaromatics by interfacial effects
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作者 HUANG Rui LIU Shengjie +1 位作者 WU Qingyuan ZHENG Nanfeng 《无机化学学报》 北大核心 2025年第1期201-212,共12页
The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts c... The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts contained Pd species in mixed valence states,with high valence Pd at the metal‑support interface and zero valence Pd at the metal surface.While the strong coordination of triphenylphosphine(PPh3)to Pd0 on the Pd surface prevents the adsorption of halogenated nitroaromatics and thus dehalogenation,the coordination of sodium metavanadate(NaVO3)to high‑valence Pd sites at the interface helps to activate H2 in a heterolytic pathway for the selective hydrogenation of nitro‑groups.The excellent catalytic performance of the interfacial active sites enables the selective hydrogenation of a wide range of halogenated nitroaromatics. 展开更多
关键词 halogenated nitroaromatic heterogeneous catalysis HYDROGENATION selectivity control interfacial effect
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Controlling Reactivity of Palladium Amides for Selective Carbonylation towards Urea and Oxamide Derivatives
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作者 WANG Jin-hui CAO Yan-wei HE Lin 《分子催化(中英文)》 CAS CSCD 北大核心 2024年第4期297-308,共12页
Carbonylation reactions,crucial for carbonyl group incorporation,struggle with the inherent complexity of achieving selective mono-or double-carbonylation on single substrates,often due to competing reaction pathways.... Carbonylation reactions,crucial for carbonyl group incorporation,struggle with the inherent complexity of achieving selective mono-or double-carbonylation on single substrates,often due to competing reaction pathways.Herein,our study introduces a strategy employing palladium amides,harnessing their unique reactivity control,to direct the selective carbonylation of amines for the targeted synthesis of urea and oxamide derivatives.The palladium amide structure was elucidated using single-crystal X-ray diffraction.Controlled experiments and cyclic voltammetry studies further elucidate that the oxidation of palladium amide or its insertion into a carbonyl group diverges into distinct pathways.By employing sodium percarbonate as an eco-friendly oxidant and base,we have successfully constructed a switchable carbonylation system co-catalyzed by palladium and iodide under room temperature.The utilizing strategy in this study not only facilitates effective control over reaction selectivity but also mitigates the risk of explosions,a critical safety concern in traditional carbonylation methods. 展开更多
关键词 selectivity control palladium catalysis oxidative carbonylation AMINOCARBONYLATION green reagents
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“向词坛直夺将军鼓”——论陈维崧对辛稼轩的接受 被引量:1
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作者 朱丽霞 《南阳师范学院学报》 CAS 2003年第11期61-65,共5页
在稼轩之后的词史中,几乎无人不笼罩于“稼轩风”的“晕圈效应”之中。陈维崧的词作数量在整个 词史上不仅度越稼轩而且空前绝后,在有清词坛上,首先吹响了“稼轩风”的第一声号角,揭开了令人瞩目的 “清词中兴”的历史篇章,从词风、技... 在稼轩之后的词史中,几乎无人不笼罩于“稼轩风”的“晕圈效应”之中。陈维崧的词作数量在整个 词史上不仅度越稼轩而且空前绝后,在有清词坛上,首先吹响了“稼轩风”的第一声号角,揭开了令人瞩目的 “清词中兴”的历史篇章,从词风、技法和择调诸方面对陈维崧对辛稼轩都有所接受。 展开更多
关键词 清词 词风 技法 择调 陈维崧 辛稼轩
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A Dual-polarized Frequency Selective Rasorber with a Tunable Transparent Band
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作者 SHI Tongtong ZHANG Xiaofa +4 位作者 WU Weiwei WANG Shaozhi XU Yixuan YAN Yuchen YAN Xiao 《电讯技术》 北大核心 2024年第10期1569-1575,共7页
A tunable dual polarization absorption-transmission-absorption(A-T-A)frequency selective absorbers(FSR)to address the issue of high insertion loss in current tunable FSRs is proposed.The lumped resistors are loaded on... A tunable dual polarization absorption-transmission-absorption(A-T-A)frequency selective absorbers(FSR)to address the issue of high insertion loss in current tunable FSRs is proposed.The lumped resistors are loaded onto the lossy layer to absorb electromagnetic waves within the absorption band.The varactor diodes are loaded onto another lossless layer to control the transmission frequency band of the FSR.Its equivalent circuit model is provided.The proposed tunable FSR can change the passband within the range of 14.5~15.5 GHz by changing the bias voltage applied to the lossless transmission layer,while maintaining insertion loss above-1.67 dB.The series resonant structure of the lossy layer generates bilateral absorption bands between 10.2~13.5 GHz and 17.2~22 GHz,with broadband reflection suppression ranging from 10.3 GHz to 22 GHz(70.7%).The prototype is manufactured,and the measured results have verified the simulation results. 展开更多
关键词 tunable frequency selective rasorber DUAL-POLARIZATION RCS reduction stealthy radomes
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Construction and realization of the knowledge base and inference engine of an IDSS model for air-conditioning cooling/heating sources selection
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作者 刘颖 王如竹 +1 位作者 李云飞 张小松 《Journal of Southeast University(English Edition)》 EI CAS 2003年第2期136-141,共6页
The knowledge representation mode and inference control strategy were analyzed according to the specialties of air-conditioning cooling/heating sources selection. The constructing idea and working procedure for knowle... The knowledge representation mode and inference control strategy were analyzed according to the specialties of air-conditioning cooling/heating sources selection. The constructing idea and working procedure for knowledge base and inference engine were proposed while the realization technique of the C language was discussed. An intelligent decision support system (IDSS) model based on such knowledge representation and inference mechanism was developed by domain engineers. The model was verified to have a small kernel and powerful capability in list processing and data driving, which was successfully used in the design of a cooling/heating sources system for a large-sized office building. 展开更多
关键词 AIR-CONDITIONING cooling/heating sources intelligent decision support system knowledge base inference engine
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Infection of the Anther-smut Microbotryum violaceum in Populations of Silene dioica: Variation in Floral Morphology, Patterns of Spore Deposition and Pathogen-Pollinator Mediated Selection
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作者 刘登义 Ulla CARLSSON 《Acta Botanica Sinica》 CSCD 2002年第1期88-96,共9页
The anther-smut Microbotryum violaceum ( Brandenburger and Schvinn) G. Deml. and Oberw.) causes a systematic infection of its host Silene dioica ( L.) Clairv., resulting in sterility and production of teliospores (dis... The anther-smut Microbotryum violaceum ( Brandenburger and Schvinn) G. Deml. and Oberw.) causes a systematic infection of its host Silene dioica ( L.) Clairv., resulting in sterility and production of teliospores (dispersal propagules) in flowers. These spores are transmitted to healthy plants mainly by flower visitors. The behavioral responses of flower visitors to a variation in floral characters are not only likely to affect rates of pollen export/import, but also the rate of spore deposition and probability of disease. In a transplantation experiment, using plants from four different populations, we tested for correlation between variation in female floral morphology and patterns of spore and pollen deposition, and a resulting risk of disease. The source populations in this experiment were located on four islands in Skeppsvik archipelago in northern Sweden, and represented a gradient of disease incidence from completely healthy ( Island 1), low incidence ( Island 2) to high incidences ( Islands 3 and 4) of disease. Fifty plants from each population were transplanted to the center, of the population on Island 4. There were significant differences among the transplants in floral characters, i.e. corolla size, style length and ovule number. Plants from the non-diseased population had larger flowers and longer styles than plants from the highly diseased populations. Numbers of pollen grains and spores deposited on flowers were strongly and positively correlated. We found that plants originating from the non-diseased population captured approximately 4 times more pollen and 9 times more spores, per flower than die individuals from the resident population (Island 4, population 4). The incidences of disease among plants, from the four populations differed significantly, and was 37%, 20%, 18% and 0 for populations 1, 2, 3 and 4 respectively. In a survey of ten populations we found a significant negative correlation between the mean style length ( positively correlated with corolla size and ovule number) among healthy plants and incidence of disease in these populations. The potentiality for pathogen-pollinator mediated selection oil floral characters; and consequences for gone flow between populations of Silene dioica are discussed. 展开更多
关键词 Silene dioica floral morphology anther-smut infection patterns of spore deposition pathogen-pollinator mediated selection
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Confinement effect of carbon nanotubes on the product distribution of selective hydrogenation of cinnamaldehyde 被引量:7
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作者 Hongfei Ma Tie Yu +1 位作者 Xiulian Pan Xinhe Bao 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第8期1315-1321,共7页
The catalytic activity of metal catalysts can be modulated by confinement within the channels of carbon nanotubes(CNTs).Here,we show that the product distribution of cinnamaldehyde hydrogenation can be modified by con... The catalytic activity of metal catalysts can be modulated by confinement within the channels of carbon nanotubes(CNTs).Here,we show that the product distribution of cinnamaldehyde hydrogenation can be modified by confinement of Ru nanoparticles in CNTs.A catalyst composed of Ru nanoparticles dispersed on the exterior walls of CNTs gave hydrocinnamaldehyde as product.In contrast,confinement of the Ru nanoparticles within CNT channels facilitated hydrogenation of C=O bonds and complete hydrogenation,and both cinnamyl alcohol and hydrocinnamyl alcohol formed in addition to hydrocinnamaldehyde.High‐resolution transmission electron microscopy,Raman spectroscopy,hydrogen temperature‐programmed reduction,and hydrogen temperature‐programmed desorption were used to investigate the characteristics of the catalysts.The results indicate that the different interactions between the confined Ru nanoparticles and the exterior and interior walls of the CNTs,as well as spatial restriction and enrichment within the narrow channels likely play important roles in modulation of the product distribution. 展开更多
关键词 Carbon nanotubes Confined catalysis RUTHENIUM Selective hydrogenation CINNAMALDEHYDE Selectivity modulation
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Tuning catalytic selectivity of propane oxidative dehydrogenation via surface polymeric phosphate modification on nickel oxide nanoparticles 被引量:2
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作者 Kaimin Du Mengjia Hao +5 位作者 Zhinian Li Wei Hong Juanjuan Liu Liping Xiao Shihui Zou Jie Fan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第7期1057-1062,共6页
Thermal stability has long been recognized as a major limitation for the application of ligand modification in high-temperature reactions. Herein, we demonstrate polymeric phosphate as an efficient and stable ligand t... Thermal stability has long been recognized as a major limitation for the application of ligand modification in high-temperature reactions. Herein, we demonstrate polymeric phosphate as an efficient and stable ligand to tune the selectivity of propane oxidative dehydrogenation. Beneficial from the weakened affinity of propene, NiO modified with polymeric phosphate shows a selectivity 2–3 times higher than NiO towards the production of propene. The success of this regulation verifies the feasibility of ligand modification in high-temperature gas-phase reactions and shines a light on its applications in other important industrial reactions. 展开更多
关键词 Nickel oxide nanoparticle Surface polymeric phosphate Propane oxidative dehydrogenation Tuning selectivity Adsorption
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Ru/FeO_x catalyst performance design: Highly dispersed Ru species for selective carbon dioxide hydrogenation 被引量:2
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作者 Di Zhang Jingjie Luo +5 位作者 Jiajie Wang Xin Xiao Yuefeng Liu Wei Qi Dang Sheng Su Wei Chu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第1期157-166,共10页
A series of Ru/FeOx catalysts were synthesized for the selective hydrogenation of CO2to CO.Detailed characterizations of the catalysts through X‐ray diffraction,X‐ray photoelectron spectroscopy,transmission electron... A series of Ru/FeOx catalysts were synthesized for the selective hydrogenation of CO2to CO.Detailed characterizations of the catalysts through X‐ray diffraction,X‐ray photoelectron spectroscopy,transmission electron microscopy,and temperature‐programmed techniques were performed to directly monitor the surface chemical properties and the catalytic performance to elucidate the reaction mechanism.Highly dispersed Ru species were observed on the surface of FeOx regardless of the initial Ru loading.Varying the Ru loading resulted in changes to the Ru coverage over the FeOx surface,which had a significant impact on the interaction between Ru and adsorbed H,and concomitantly,the H2activation capacity via the ability for H2dissociation.FeOx having0.01%of Ru loading exhibited100%selectivity toward CO resulting from the very strong interaction between Ru and adsorbed H,which limits the desorption of the activated H species and hinders over‐reduction of CO to CH4.Further increasing the Ru loading of the catalysts to above0.01%resulted in the adsorbed H to be easily dissociated,as a result of a weaker interaction with Ru,which allowed excessive CO reduction to produce CH4.Understanding how to selectively design the catalyst by tuning the initial loading of the active phase has broader implications on the design of supported metal catalysts toward preparing liquid fuels from CO2.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences toward preparing liquid fuels from CO2.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved. 展开更多
关键词 Highly dispersed Ru/FeOx catalyst Temperature‐programmed surface reaction CO2 selective hydrogenation Product selectivity Hydrogen adsorption
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Adaptive Parameter Selection for Total Variation Image Deconvolution 被引量:3
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作者 You-Wei Wen Andy M. Yip 《Numerical Mathematics(Theory,Methods and Applications)》 SCIE 2009年第4期427-438,共12页
In this paper,we propose a discrepancy rule-based method to automatically choose the regularization parameters for total variation image restoration problems. The regularization parameters are adjusted dynamically in ... In this paper,we propose a discrepancy rule-based method to automatically choose the regularization parameters for total variation image restoration problems. The regularization parameters are adjusted dynamically in each iteration.Numerical results are shown to illustrate the performance of the proposed method. 展开更多
关键词 Image restoration regularization parameter total variation.
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A Wavelength Tunable DBR Laser Integrated with an Electro-Absorption Modulator by a Combined Method of SAG and QWI
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作者 张靖 李宝霞 +5 位作者 赵玲娟 王保军 周帆 朱洪亮 边静 王圩 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第11期2053-2057,共5页
We report a wavelength tunable electro-absorption modulated DBR laser based on a combined method of SAG and QWI. The threshold current is 37mA and the output power at 100mA gain current is 3.5mW. When coupled to a sin... We report a wavelength tunable electro-absorption modulated DBR laser based on a combined method of SAG and QWI. The threshold current is 37mA and the output power at 100mA gain current is 3.5mW. When coupled to a single-mode fiber with a coupling efficiency of 15% ,more than a 20dB extinction ratio is observed over the change of EAM bias from 0 to -2V. The 4.4nm continuous wavelength tuning range covers 6 channels on a 100GHz grid for WDM telecommunications. 展开更多
关键词 tunable lasers distributed Bragg reflector lasers electroabsorption modulator quantum-well intermi-xing selective area growth
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Excess Commuting in Transitional Urban China:A Case Study of Guangzhou 被引量:5
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作者 LIU Wangbao HOU Quan 《Chinese Geographical Science》 SCIE CSCD 2016年第5期599-608,共10页
During the reform era, Chinese cities witnessed dramatic institutional transformation and spatial restructuring in general and profound change of commuting patterns in particular. Using household surveys collected in ... During the reform era, Chinese cities witnessed dramatic institutional transformation and spatial restructuring in general and profound change of commuting patterns in particular. Using household surveys collected in Guangzhou, China, in 2001, 2005 and 2010, excess commuting measurements are estimated. Excess commuting shows an overall trend of increasing during 1990–1999, and then declining during 2000–2010. We argue that deepening marketization of the jobs and housing sectors has induced spatial separation of jobs and housing. In other words, institutional transition and urban spatial restructuring are underpinning the changes of commuting patterns in Chinese cities. Excess commuting has strong relationship with individual socio-demographic status, which is by and large due to the increasing flexibilities of jobs and housing location choices enjoyed by urban residents. The findings call for considerations on balancing jobs-housing in making public policies relevant to urban development in general, and land use and transportation in particular. 展开更多
关键词 excess commuting jobs-housing balance spatial restructuring GUANGZHOU China
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Appraisal of Common Dispute Problems on Public Works Projects in Thailand
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作者 Borvom Israngkura Na Ayudhya 《Journal of Civil Engineering and Architecture》 2011年第10期928-936,共9页
The objectives of this research were to identify and appraising the common dispute problems in domestic and international funded public works projects. The interview and questionnaire method were used in this research... The objectives of this research were to identify and appraising the common dispute problems in domestic and international funded public works projects. The interview and questionnaire method were used in this research. Randomly distributed questionnaire technique was applied to select samples of 390 various construction practitioners consisting of owners, consultants and main contractors to evaluate the severity of the 43 identified dispute factors. This survey found that contract and specification dispute problem was the highest concern among four main dispute problems for construction practitioners. The insufficient working drawing details factor was ranked as the highest overall severity index. The results of the survey also indicated that both domestic and international funded public projects faced moderately severe dispute level among construction team. 展开更多
关键词 Construction dispute public works developing countries.
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Multilingualism and the Choice of a Language for Anglophone Education in Cameroon
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作者 Paul Mbufong 《Sino-US English Teaching》 2013年第6期473-477,共5页
This paper seeks to do three things: (1) examine the linguistic situation of Cameroon; (2) identify the language(s) used in education; and (3) discuss whether in the light of the social linguistic evidence, t... This paper seeks to do three things: (1) examine the linguistic situation of Cameroon; (2) identify the language(s) used in education; and (3) discuss whether in the light of the social linguistic evidence, the current choice of language for education (English) is well motivated. The methodology employed is a socio-lin some randomly selected urban centers in Cameroon for example, Buea, Bamenda, Kumba, guistic survey of etc.. The results suggest among other things: (1) that Cameroon is a highly multilingual country with over 280 home languages and (2) that while English is the language for Anglophone education, Pidgin English is actually the predominant language and the first language for most Anglophones. Based on these findings, the author proposes Pidgin English as the choice language for early education in Anglophone Cameroon (the southwest and northwest regions). Pidgin English is the only language which expresses Cameroonian reality. It is spoken by more than 70% of the population. It is the only language that is not associated with a particular tribe, religion, or with a specific colonial government. 展开更多
关键词 MULTILINGUALISM Anglophone PIDGIN
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A novel interactive preferential evolutionary method for controller tuning in chemical processes
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作者 宿翀 李宏光 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第2期398-411,共14页
In response to many multi-attribute decision-making(MADM)problems involved in chemical processes such as controller tuning,which suffer human's subjective preferential nature in human–computer interactions,a nove... In response to many multi-attribute decision-making(MADM)problems involved in chemical processes such as controller tuning,which suffer human's subjective preferential nature in human–computer interactions,a novel affective computing and preferential evolutionary solution is proposed to adapt human–computer interaction mechanism.Based on the stimulating response mechanism,an improved affective computing model is introduced to quantify decision maker's preference in selections of interactive evolutionary computing.In addition,the mathematical relationship between affective space and decision maker's preferences is constructed.Subsequently,a human–computer interactive preferential evolutionary algorithm for MADM problems is proposed,which deals with attribute weights and optimal solutions based on preferential evolution metrics.To exemplify applications of the proposed methods,some test functions and,emphatically,controller tuning issues associated with a chemical process are investigated,giving satisfactory results. 展开更多
关键词 PREFERENCE Affective computing Interactive evolutionary computation Multi-attribute decision-making Controller tuning
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An Electroabsorption Modulator Monolithically Integrated with a Semiconductor Optical Amplifier and a Dual-Waveguide Spot-Size Converter
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作者 侯廉平 王圩 +3 位作者 朱洪亮 周帆 王鲁峰 边静 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第8期1504-1508,共5页
A semiconductor optical amplifier and electroabsorption modulator monolithically integrated with a spotsize converter input and output is fabricated by means of selective area growth,quantum well intermixing,and asymm... A semiconductor optical amplifier and electroabsorption modulator monolithically integrated with a spotsize converter input and output is fabricated by means of selective area growth,quantum well intermixing,and asymmetric twin waveguide technology. A 1550-1600nm lossless operation with a high DC extinction ratio of 25dB and more than 10GHz 3dB bandwidth are successfully achieved. The output beam divergence angles of the device in the horizontal and vertical directions are as small as 7.3°× 18.0°, respectively, resulting in a 3.0dB coupling loss with a cleaved single-mode optical fiber. 展开更多
关键词 semiconductor optical amplifier electroabsorption modulator spot-size converters selective area growth quantum well intermixing asymmetric twin waveguide
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Surface regulated Ni nanoparticles on N-doped mesoporous carbon as an efficient electrocatalyst for CO_(2)reduction 被引量:3
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作者 Min Wang Qi Xie +3 位作者 Huimin Chen Guangbo Liu Xuejing Cui Luhua Jiang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第12期2306-2312,共7页
Low cost,highly selective and efficient electrocatalysts for CO_(2)reduction reaction(CO_(2)RR)is crucial for lowering the global carbon footprint and mitigating energy shortages.Here,we first report a highly selectiv... Low cost,highly selective and efficient electrocatalysts for CO_(2)reduction reaction(CO_(2)RR)is crucial for lowering the global carbon footprint and mitigating energy shortages.Here,we first report a highly selective and efficient electrocatalyst for CO_(2)RR to CO using a surface-regulated Ni nanoparticles supported on N-doped CMK-3(N,O-Ni/CMK3).Compared with most Ni metal catalysts previously reported with severe competitive hydrogen evolution during the CO_(2)RR,the N,O-Ni/CMK3 catalyst presents a superior CO faradaic efficiency of about 97%,a high CO partial current density(13.01 mA cm^(-1))and turnover frequency(4.25 s^(–1)).The comprehensive characterization provides evidence that the N,O co-regulated Ni acts as the active center.Taking advantage of the N,O co-regulated chemical environment,N,O-Ni/CMK3 also displays a decent stability at negative potentials.Our work paves a novel approach for developing transition metal catalysts for CO_(2)RR with enhanced activity and selectivity via regulating surface chemical environment. 展开更多
关键词 CO_(2)electro-reduction reaction Ni nanoparticle N-doped mesoporous carbon Surface regulation High selectivity
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Chemo-selective couplings of anilines and acroleins/enones under substrate control and condition control
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作者 Xukai Zhou Jiaqiong Sun Xingwei Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第11期1782-1791,共10页
Rh(III)‐catalyzed C–H activation of N‐protected anilines and chemo‐divergent couplings with acroleins/enones have been realized for synthesis of three classes of heterocycles.The oxidative coupling of N‐pyridylan... Rh(III)‐catalyzed C–H activation of N‐protected anilines and chemo‐divergent couplings with acroleins/enones have been realized for synthesis of three classes of heterocycles.The oxidative coupling of N‐pyridylaniline afforded dihydroquinolones with the acrolein being a major hydrogen acceptor.When the directing group was replaced by pyrimidyl in the same system,redox‐neutral coupling occurred to afford hemiaminal ethers.Oxidative annulation of N‐pyridylanilines with enones using AgBF4 oxidant afforded atropisomeric quinolinium salts. 展开更多
关键词 Rh(III)‐catalysis Chemo‐selectivity ANNULATION Substrate control Condition control
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