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Databases of 2D material-substrate interfaces and 2D charged building blocks
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作者 邓俊 潘金波 杜世萱 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期34-38,共5页
Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new mater... Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new materials in this respect.In van der Waals(vdW)layered materials,these building blocks are charge neutral and can be isolated from their bulk phase(top-down),but usually grow on substrate.In ionic layered materials,they are charged and usually cannot exist independently but can serve as motifs to construct new materials(bottom-up).In this paper,we introduce our recently constructed databases for 2D material-substrate interface(2DMSI),and 2D charged building blocks.For 2DMSI database,we systematically build a workflow to predict appropriate substrates and their geometries at substrates,and construct the 2DMSI database.For the 2D charged building block database,1208 entries from bulk material database are identified.Information of crystal structure,valence state,source,dimension and so on is provided for each entry with a json format.We also show its application in designing and searching for new functional layered materials.The 2DMSI database,building block database,and designed layered materials are available in Science Data Bank at https://doi.org/10.57760/sciencedb.j00113.00188. 展开更多
关键词 2D material-substrate interfaces charged building block database functional-oriented materials design layered materials density functional theory
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A novel 300 kW arc plasma inverter system based on hierarchical controlled building block structure 被引量:4
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作者 王振民 黄石生 《China Welding》 EI CAS 2008年第4期12-16,共5页
To date, the high power arc plasma technology is widely used. A next generation high power arc plasma system based on building block structure is presented. The whole arc plasma inverter system is composed of 12 paral... To date, the high power arc plasma technology is widely used. A next generation high power arc plasma system based on building block structure is presented. The whole arc plasma inverter system is composed of 12 paralleled units to increase the system output capability. The hierarchical control system is adopted to improve the reliability and flexibility of the high power arc plasma inverter. To ensure the reliable turn on and off of the IGBT module in each building block unit, a special pulse drive circuit is designed by using pulse transformer. The experimental result indicates that the high power arc plasma inverter system can transfer 300 kW arc plasma energy reliably with high efficiency. 展开更多
关键词 PLASMA plasma inverter hierarchical system pulse drive circuit building block structure
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Preparation, Structure and Properties of 3D Supramolecular Architecture, on the Basis of Hydrogen Bonds and π-π Stacking Between 2D Layers, with Windmill Building Blocks
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作者 YU Li-qiong HUANG Ru-dan CHI Ying-nan HU Chang-wen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第3期251-254,共4页
A novel three-dimensional(3D) supramolecular architecture, {[Nd(OH-BDC)(OH-HBDC)(H2O)2]·2HaO)n(1) (OH-H2BDC=5-hydroxyisophthalic acid), which was formed through hydrogen bonds and π-π stacking betw... A novel three-dimensional(3D) supramolecular architecture, {[Nd(OH-BDC)(OH-HBDC)(H2O)2]·2HaO)n(1) (OH-H2BDC=5-hydroxyisophthalic acid), which was formed through hydrogen bonds and π-π stacking between two-dimensional(2D) layers, was hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Windmill building blocks, which consist of two nine-coordinated metal centers and four OH-H2BDC groups are connected through two carboxyl groups, to lead to a one-dimensional infinite inorganic chain(… M--O--C--O--M…) along the [100] direction. An observed intense blue luminescence with an emission band peaked at 390 nm for compound 1 may results from ligand-to-metal charge transfer(LMCT). Variable-temperature magnetic susceptibility of compound 1 was investigated and the value was deviated from the Curie-Weiss law. 展开更多
关键词 building block π-π stacking Hydrogen bond Luminescence MAGNETISM
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Two Chiral Building Blocks for the Stereocontrolled Synthesis of Anti-and Syn-1,3-Diols
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作者 Yong WU Mei GUAN +2 位作者 Zheng XU Li Cheng Xiao Chun WU 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第9期765-766,共2页
Two chiral building blocks 1 and 2 for anti-and syn-1, 3-diols has been achieved in 8 steps and 7 steps respectively, starting from the readily available and inexpensive D (+)-xylose 3.
关键词 Chiral building block anti-and syn-1 3-diols D (+)-xylose
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Ethyl 2-diazo-3-oxo-perfluorocarboxylates as a Potentially Fluorine-containing Building Block:[Rh(OAc)_2]_2-Catalyzed Reaction with Nitriles
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期241-241,共1页
关键词 Rh OAC Ethyl 2-diazo-3-oxo-perfluorocarboxylates as a Potentially Fluorine-containing building block Catalyzed Reaction with Nitriles
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(Z)-ETHYL 3-BROMO-4,4,4-TRIFLUORO-2-BUTENOATE AS A NOVEL CF_3-CONTAINING BUILDING BLOCK: Its Preparation and Pd-Catalysed Reaction with Alkynes and Organozinc Reagents
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作者 Wei Yuan HUANG, Long Lǔ Shanghai Institute of Organic Chemistry, The Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第10期769-772,共4页
A novel CF_3-containing building block, (Z)-ethyl 3-bromo-4,4,4-trifluoro-2-butenoate, was easily prepared from CF_3CBr_3, the former reacted with alkynes Or organozinc reagents in the presence of Pd complexes to affo... A novel CF_3-containing building block, (Z)-ethyl 3-bromo-4,4,4-trifluoro-2-butenoate, was easily prepared from CF_3CBr_3, the former reacted with alkynes Or organozinc reagents in the presence of Pd complexes to afford useful CF_3-containing intermediates in good yield. 展开更多
关键词 CF Br ETHYL 3-BROMO-4 4 4-TRIFLUORO-2-BUTENOATE AS A NOVEL CF3-CONTAINING building block Its Preparation and Pd-Catalysed Reaction with Alkynes and Organozinc Reagents PD AS
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STUDIES ON THE SYNTHESIS OF RABDOSIA DITERPENOID Ⅱ,PREPARATION OF A KEY BUILDING BLOCK,α,β-UNSATURATED LACTONE
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作者 Zhi Min WANG Wei Shan ZHOU Shanghai Institute of Organic Chemistry,Academia Sinica,345 Lingling Lu,Shanghai 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第1期71-74,共4页
The main half molecule(4a)of the trichorabdal B(1) was synthesized from pentadienol(6).The key step is the intramolecular Diels-Alder reaction of 8.
关键词 THF PREPARATION OF A KEY building block STUDIES ON THE SYNTHESIS OF RABDOSIA DITERPENOID UNSATURATED LACTONE
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Biobased Vanillic Acid and Ricinoleic Acid: Building Blocks for Fully Renewable Copolyesters
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作者 Claudio Gioia Maria Barbara Banella +5 位作者 Grazia Totaro Micaela Vannini Paola Marchese Martino Colonna Laura Sisti Annamaria Celli 《Journal of Renewable Materials》 SCIE 2018年第1期126-135,共10页
New fully biobased polyether/esters have been synthesized by a one-pot polymerization reaction of ricinoleic acid(RA),vanillic acid(VA)and ethylene carbonate(EC).In particular,EC selectively reacts with the phenolic g... New fully biobased polyether/esters have been synthesized by a one-pot polymerization reaction of ricinoleic acid(RA),vanillic acid(VA)and ethylene carbonate(EC).In particular,EC selectively reacts with the phenolic group of VA to obtain in-situ 4-(2-hydroxyethoxy)-3-methoxybenzoate(EV),suitable for subsequent copolymerization with RA.The procedure was carried out in a single step,without any solvent.Chemical structure and thermal properties of the new materials were studied in order to explore relationships between composition and final performances.The combination of EV,bearing a rigid aromatic structure,with RA,characterized by high flexibility and potential biocidal activity,allows the production of a novel class of fully biobased aliphatic-aromatic polymers presenting tuneable thermal properties and suitable for a range of applications,for example,in active packaging and biomedical fields. 展开更多
关键词 Biobased building blocks vanillic acid ricinoleic acid COPOLYESTERS
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Compliant semiconductor scaffolds: building blocks for advanced neural interfaces
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作者 Francesca Cavallo 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第11期1741-1742,共2页
Neuroscience,neuroprosthetics and neural regeneration would benefit from more adequate interfacing devices.To understand how neurons communicate,process information and control behavior,researchers need to monitor ner... Neuroscience,neuroprosthetics and neural regeneration would benefit from more adequate interfacing devices.To understand how neurons communicate,process information and control behavior,researchers need to monitor nerve cell activity with high specifity and high spatio-temporal resolution.Neural prostheses require minimally invasive-implantable devices to re- place lost function, and bypass dysfunctional pathways in the nervous system. Devices built to repair damaged nerves have to support and promote regeneration of host neurons through an injured area. Finally, as neuromodulation is being elevated from last resort to first choice treatment for an increasing number of conditions, implantable devices able to perform targeted regu- lation of neural activity are needed. Recent advances in device miniaturization, materials engineering, and nanotechnology are enabling development of an increasing number of devices that effectively interface with neural circuits. Wireless spinal cord and deep brain stimulators, retinal and cochlear implants, high density electrodes arrays for neural recording have already proven to significantly impact fundamental research in neuro- science, as well as individuals' quality of life. 展开更多
关键词 HIGH building blocks for advanced neural interfaces Compliant semiconductor scaffolds
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Appropriate schemata and building blocks
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作者 YangHaijun LiMinqiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期451-455,F003,共6页
Appropriate schemata as a novel concept to characterize building blocks are introduced, and then, the traits of appropriate schemata are presented. The effects of building blocks by search operators are analyzed. Henc... Appropriate schemata as a novel concept to characterize building blocks are introduced, and then, the traits of appropriate schemata are presented. The effects of building blocks by search operators are analyzed. Hence, the experiments on RR-8X8 are employed to verify that appropriate schemata construct the building blocks. The validity of appropriate schemata and building blocks from the views of theory and practice is presented. 展开更多
关键词 genetic algorithms appropriate schemata building blocks.
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Preparation and Stereospecified Suzuki Reaction of a Resin Bound CF_3-Containing Building Block
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期310-310,共1页
关键词 CF Preparation and Stereospecified Suzuki Reaction of a Resin Bound CF3-Containing building block
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Solving Job-Shop Scheduling Problems by Genetic Algorithms Based on Building Block Hypothesis
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作者 CHENG Rong CHEN You-ping LI Zhi-gang 《International Journal of Plant Engineering and Management》 2006年第2期119-123,共5页
In this paper, we propose a new genetic algorithm for job-shop scheduling problems (JSP). The proposed method uses the operation-based representation, based on schema theorem and building block hypothesis, a new cro... In this paper, we propose a new genetic algorithm for job-shop scheduling problems (JSP). The proposed method uses the operation-based representation, based on schema theorem and building block hypothesis, a new crossover is proposed : By selecting short, low order highly fit schemas to genetic operator, the crossover can exchange meaningful ordering information of parents effectively and can search the global optimization. Simulation results on MT benchmark problem coded by C + + show that our genetic operators are very powerful and suitable to job-shop scheduling problems and our method outperforms the previous GA-based approaches. 展开更多
关键词 job-shop scheduling genetic algorithm schema theorem building block hypothesis
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A research on building block type miniature harvester
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作者 LAN Wenfeng,CHEN Jinbao,QIU Xianjun,and LIU Maorong,Fujian Machinery Res Inst,Fuzhou,China 《Chinese Rice Research Newsletter》 1994年第4期8-8,共1页
In this invention, the procedure of cutting, conveying, threshing and transporting stalks are carried out by a set of conveying chains ( see figure). The axis of the main drum 2 is placed horizontally transverse (vert... In this invention, the procedure of cutting, conveying, threshing and transporting stalks are carried out by a set of conveying chains ( see figure). The axis of the main drum 2 is placed horizontally transverse (vertical to the forward direction). The upper and the lower conveying chains 8, 10 as well as cutterbar 11 are mounted in the lower part of the axial feed opening. Several star well 9 and plastic stalk-pressing rod are filled at the front of the lower conveying chain, and a spring stalk pressing assembly at the rear. The residue after threshing is discharged by star seels 18, 34. The staiks are placed near the cutterbar 11. Once the stalks are cut off by the cutterbar, they 展开更多
关键词 TYPE A research on building block type miniature harvester
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Building Blocks
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作者 Funeka Yazini April 《ChinAfrica》 2016年第9期10-11,共2页
Building Blocks Funeka Yazini AprilAfrican governments, not the Americans or the Chinese, have the key responsibility to become the drivers of their own industrial and agricul- tural development. There- fore, it is ur... Building Blocks Funeka Yazini AprilAfrican governments, not the Americans or the Chinese, have the key responsibility to become the drivers of their own industrial and agricul- tural development. There- fore, it is urgent that African governments prioritize the objectives of the Johannes- burg Summit of the Forum on China-Africa Cooperation (FOCAC) domestically and regionally. 展开更多
关键词 building blocks
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Synthesis of an Anti-1,3-Diol Type Chiral Building Block
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作者 Wu, Y Guan, M 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第11期987-988,共2页
关键词 chiral building block anti-1 3-Diol D(+)-xylose
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A highly reduced Mo_(74) polyoxometalate featuring high proton conductivity accessed by building block strategy
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作者 Shi-Yi Liu Xue-Xin Li +4 位作者 Wei-Chao Chen Kui-Zhan Shao Xin-Long Wang Chao Qin Zhong-Min Su 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第3期862-868,共7页
Highly reduced polyoxometalates(POMs) are predicted to be used as rather high energy density materials;however,it still suffers from the limited cluster species and reduction ratio.Here we demonstrate that it is possi... Highly reduced polyoxometalates(POMs) are predicted to be used as rather high energy density materials;however,it still suffers from the limited cluster species and reduction ratio.Here we demonstrate that it is possible to employ the building block strategy to generate a highly reduced polyoxomolybdate(C_(2)H_(8)N)_(14)(NH_(4))_(4)H_(14)[Mo_(48)-ⅤMo_(26)ⅥO_(202)(OH)_(12)(SO_(4))_(6)]·46H_(2)O(Mo_(74)).The fundamental Mo-based{Mo_x}(x=4,5,and 6) building blocks,which are templated by tetra-coordinated anions{MoO_(4)}or{SO_(4)},not only lay foundation for the formation of Mo_(74) featuring an unprecedented reduction ratio of 65%,but also give rise to SBBs-mediated(secondary building blocks) supramolecular dense packing interactions among the isolated Mo_(74) clusters that are favorable for proton conduction.Remarkably,high proton conductivity(2.04×10^(-2)S cm^(-1)) had been realized at 50℃ and 90% relative humidity,revealing one of the well-known POMs-based crystalline proton conducting materials.This result highlights that this building block approach possesses great potential in producing highly reduced POM systems that can achieve controllable reduced ratio and desirable properties. 展开更多
关键词 POLYOXOMETALATE building block MOLYBDENUM highly reduced state proton conduction
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A Simple Building Block with Noncovalently Conformational Locks towards Constructing Low-Cost and High-Performance Nonfused Ring Electron Acceptors 被引量:4
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作者 Xiao-Bin Gu Jin-Hua Gao +7 位作者 Zi-Yang Han Yu-Hao Shi Ya-Nan Wei Yin-Cheng Zhang Qian Peng Zhi-Xiang Wei Xin Zhang Hui Huang 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2023年第4期556-563,I0008,共9页
Nonfused ring electron acceptors(NFREAs)have attracted much attention due to their concise synthetic routes and low cost.However,developing high-performance NFREAs with simple structure remains a great challenge.In th... Nonfused ring electron acceptors(NFREAs)have attracted much attention due to their concise synthetic routes and low cost.However,developing high-performance NFREAs with simple structure remains a great challenge.In this work,a simple building block(POBT)with noncovalently conformational locks(No CLs)was designed and synthesized.Single-crystal X-ray study indicated the presence of S…O NOCLs in POBT,thus enabling it to possess a coplanar conformation comparable to that of fused-ring CPT.Two novel NFREAs based on CPT and POBT were developed,namely TT-CPT and TT-POBT,respectively.Besides,TT-POBT possessed a smaller Stokes shift and a reduced reorganization energy compared with TT-CPT,indicating the introduction of S…O No CLs can enhance the molecular rigidity even if simplifying the molecular structure.As a result,the TT-POBT-based PSC device afforded an impressive power conversion efficiency of 11.15%,much higher than that of TT-CPT counterpart(7.03%),mainly resulting from the tighterπ-πstacking,improved and balanced charge transport,and more favorable film morphology.This work demonstrates the potential of the simple building block POBT with No CLs towards constructing low-cost and highperformance NFREAs. 展开更多
关键词 Polymer solar cells Nonfused ring electron acceptors Simple building block Noncovalent conformation locks Reorganization energy
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A Cyano-Substituted Organoboron Electron-deficient Building Block for D-A Type Conjugated Polymers
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作者 Meng-Yu Liu Xing-Xin Shao +1 位作者 Jun Liu Li-Xiang Wang 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2023年第5期832-838,I0012,共8页
The development of donor-acceptor(D-A)type conjugated polymers depends largely on the design of novel A building blocks.Herein,we report a novel A building block based on the cyano-substituted organoboron unit(SBN-3).... The development of donor-acceptor(D-A)type conjugated polymers depends largely on the design of novel A building blocks.Herein,we report a novel A building block based on the cyano-substituted organoboron unit(SBN-3).Compared with the most common fluorine-substituted B←N unit,SBN-3 displays a significantly downshifted LUMO energy level because of the strong electron-withdrawing ability of cyano groups.In addition,due to the greater impact of cyano substitution on LUMO than on HOMO,SBN-3 exhibits a reduced band gap,nearinfrared absorption and fluorescence properties.The D-A type conjugated polymers based on the cyano-substituted B←N unit with thiophene-based units show narrow optical band gaps of ca.1.3 e V as well as distinctive electronic structures,i.e.,delocalized LUMOs and localized HOMOs.This work thus provides not only an effective approach to design strong A units but also a new electron-deficient building block for D-A type conjugated polymers. 展开更多
关键词 Cyano-substituted B←N unit building block Narrow band gap D-A type conjugated polymers
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An asymmetric non-fused electron-deficient building block for low-cost polymer acceptor in all-polymer solar cells
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作者 Haiqin Xiao Linfeng Yu +5 位作者 Zhiliang Zhang Haiyan Liang Yu Shi Xia Guo Maojie Zhang Yongfang Li 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第9期2626-2633,共8页
The development of polymerized fused-ring small molecule acceptors(FRA-PAs) has boosted the performance of all-polymer solar cells(all-PSCs).However,these FRA-PAs suffer from lengthy synthesis steps and high productio... The development of polymerized fused-ring small molecule acceptors(FRA-PAs) has boosted the performance of all-polymer solar cells(all-PSCs).However,these FRA-PAs suffer from lengthy synthesis steps and high production costs due to the high degree of synthetic complexity for fused-ring small molecule acceptors(FRAs).Furthermore,most FRA-PAs exhibit strong batch-to-batch variation,limiting further industrial applications.Herein,we designed and synthesized asymmetric non-fused electron-deficient building block TIC-Br with a simple structure(only three synthetic steps),showing a planar configuration,excellent electron affinity,and large dipole moment.A simple polymer acceptor PTIB was further developed by polymerization of TIC-Br and sensitized fluorinated-thienyl benzodithiophene(BDT-TF-Sn).PTIB exhibits a broad absorption from 300 to 800 nm,a suitable lowest unoccupied molecular orbital(LUMO) energy level of-3.86 e V,and moderate electron mobility(1.02×10^(-4)cm^(2)V^(-1)s^(-1)).When matched with PM6,the device achieved the best PCE of 10.11%with a high V_(OC) of 0.97 V,which is one of the highest among those reported all-PSCs.More importantly,PTIB exhibits a lower synthetic complexity index(SC=35.0%)and higher figure-of-merit values(FOM=29.0%) than all the reported high-performance PAs.The polymer also exhibits excellent batch-to-batch reproducibility and great potential for scale-up fabrication.This study indicates that TIC-Br is a promising building block for constructing low-cost polymer acceptors for large-scale applications in all-PSCs. 展开更多
关键词 non-fused electron-deficient building block low-cost polymer acceptors batch-to-batch reproducibility all-polymer solar cells
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Advanced optimization of gas turbine aero-engine transient performance using linkage-learning genetic algorithm:PartⅠ,building blocks detection and optimization in runway 被引量:5
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作者 Yinfeng LIU Soheil JAFARI Theoklis NIKOLAIDIS 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2021年第4期526-539,共14页
This paper proposes a Linkage Learning Genetic Algorithm(LLGA)based on the messy Genetic Algorithm(mGA)to optimize the Min-Max fuel controller performance in Gas Turbine Engine(GTE).For this purpose,a GTE fuel control... This paper proposes a Linkage Learning Genetic Algorithm(LLGA)based on the messy Genetic Algorithm(mGA)to optimize the Min-Max fuel controller performance in Gas Turbine Engine(GTE).For this purpose,a GTE fuel controller Simulink model based on the Min-Max selection strategy is firstly built.Then,the objective function that considers both performance indices(response time and fuel consumption)and penalty items(fluctuation,tracking error,overspeed and acceleration/deceleration)is established to quantify the controller performance.Next,the task to optimize the fuel controller is converted to find the optimization gains combination that could minimize the objective function while satisfying constraints and limitations.In order to reduce the optimization time and to avoid trapping in the local optimums,two kinds of building block detection methods including lower fitness value method and bigger fitness value change method are proposed to determine the most important bits which have more contribution on fitness value of the chromosomes.Then the procedures to apply LLGA in controller gains tuning are specified stepwise and the optimization results in runway condition are depicted subsequently.Finally,the comparison is made between the LLGA and the simple GA in GTE controller optimization to confirm the effectiveness of the proposed approach.The results show that the LLGA method can get better solution than simple GA within the same iterations or optimization time.The extension applications of the LLGA method in other flight conditions and the complete flight mission simulation will be carried out in partⅡ. 展开更多
关键词 Aeroengine control building block detection GA Global optimization GTE LLGA Min-Max controller
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