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A SUPERLINEARLY CONVERGENT SPLITTING FEASIBLE SEQUENTIAL QUADRATIC OPTIMIZATION METHOD FOR TWO-BLOCK LARGE-SCALE SMOOTH OPTIMIZATION
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作者 简金宝 张晨 刘鹏杰 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期1-24,共24页
This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method fo... This paper discusses the two-block large-scale nonconvex optimization problem with general linear constraints.Based on the ideas of splitting and sequential quadratic optimization(SQO),a new feasible descent method for the discussed problem is proposed.First,we consider the problem of quadratic optimal(QO)approximation associated with the current feasible iteration point,and we split the QO into two small-scale QOs which can be solved in parallel.Second,a feasible descent direction for the problem is obtained and a new SQO-type method is proposed,namely,splitting feasible SQO(SF-SQO)method.Moreover,under suitable conditions,we analyse the global convergence,strong convergence and rate of superlinear convergence of the SF-SQO method.Finally,preliminary numerical experiments regarding the economic dispatch of a power system are carried out,and these show that the SF-SQO method is promising. 展开更多
关键词 large scale optimization two-block smooth optimization splitting method feasible sequential quadratic optimization method superlinear convergence
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Remote Control and Telemetry System for Large-scale Model Test at Sea 被引量:3
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作者 孙树政 李积德 +2 位作者 赵晓东 栾景雷 王长涛 《Journal of Marine Science and Application》 2010年第3期280-285,共6页
Physical testing of large-scale ship models at sea is a new experimental method.It is a cheap and reliable way to research the environment adaptability of a ship in complex and extreme wave conditions.It is necessary ... Physical testing of large-scale ship models at sea is a new experimental method.It is a cheap and reliable way to research the environment adaptability of a ship in complex and extreme wave conditions.It is necessary to have a stable experimental system for the test.Since the experimental area is large, a remote control system and a telemetry system are essential, and were designed by the authors.An experiment was conducted on the Songhuajiang River to test the systems.The relationship between the model's speed and its electromotor's revolutions was also measured during the model test.The results showed that the two systems make it possible to carry out large-scale model tests at sea. 展开更多
关键词 large scale model remote control telemetry systerm model test
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A Reconfigurable Manufacturing System for In-site Machining Component with Large Scale 被引量:1
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作者 高东 武加峰 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第S1期226-230,共5页
To cope with various unpredictable changes in large scale parts,the concept of reconfigurable manufacturing system (RMS) for machining these components is presented.Considering with large-size space measurement and th... To cope with various unpredictable changes in large scale parts,the concept of reconfigurable manufacturing system (RMS) for machining these components is presented.Considering with large-size space measurement and the fixed-free manufacture mode,an automatically localizing machining method for large scale part is studied in this paper,and the architecture of the RMS for machining large scale parts is proposed.According to the method and structure,the automatically localizing model is established.The theoretical analysis and simulation examples demonstrate the feasibility and validity of the proposed method,and the results indicate that the method is suitable and effective for machining large scale components in significant scientific projects. 展开更多
关键词 large scale component reconfigurable manufacturing system automatically localizing
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Fault diagnosis method of link control system for gravitational wave detection
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作者 GAO Ai XU Shengnan +2 位作者 ZHAO Zichen SHANG Haibin XU Rui 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期922-931,共10页
To maintain the stability of the inter-satellite link for gravitational wave detection,an intelligent learning monitoring and fast warning method of the inter-satellite link control system failure is proposed.Differen... To maintain the stability of the inter-satellite link for gravitational wave detection,an intelligent learning monitoring and fast warning method of the inter-satellite link control system failure is proposed.Different from the traditional fault diagnosis optimization algorithms,the fault intelligent learning method pro-posed in this paper is able to quickly identify the faults of inter-satellite link control system despite the existence of strong cou-pling nonlinearity.By constructing a two-layer learning network,the method enables efficient joint diagnosis of fault areas and fault parameters.The simulation results show that the average identification time of the system fault area and fault parameters is 0.27 s,and the fault diagnosis efficiency is improved by 99.8%compared with the traditional algorithm. 展开更多
关键词 large scale multi-satellite formation gravitational wave detection laser link monitoring fault diagnosis deep learning
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ON DECENTRALIZED STABILIZATION OF LINEAR LARGE SCALE SYSTEMS WITH SYMMETRIC CIRCULANT STRUCTURE
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作者 金朝永 张湘伟 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第8期863-872,共10页
The decentralized stabilization of continuous and discrete linear large scale systems with symmetric circulant structure was studied.A few sufficient conditions on decentralized stabilization of such systems were prop... The decentralized stabilization of continuous and discrete linear large scale systems with symmetric circulant structure was studied.A few sufficient conditions on decentralized stabilization of such systems were proposed.For the continuous systems,by introducing a concept called the magnitude of interconnected structure,a very important property that the decentralized stabilization of such systems is fully determined by the structure of each isolated subsystem that is obtained when the magnitude of interconnected structure of the overall system is given.So the decentralized stabilization of such systems can be got by only appropriately designing or modifying the structure of each isolated subsystem,no matter how complicated the interconnected structure of the overall system is.A algorithm for obtaining decentralized state feedback to stabilize the overall system is given.The discrete systems were also discussed.The results show that there is a great dfference on decentralized stabilization between continuous case and discrete case. 展开更多
关键词 large scale system decentralized stabilization symmetric circulant structure magnitude of interconnected structure Ricatti equation
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ROBUST OBSERVER DESIGN FOR A CLASS OF UNCERTAIN NONLINEAR LARGE SCALE SYSTEMS *
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作者 姜斌 王江 王先来 《Transactions of Tianjin University》 EI CAS 1996年第2期32+29-31,共4页
In this paper, a mathematic description of a class of uncertain nonlinear large scale systems based on some practical application is given. A designing method to construct observers for su... In this paper, a mathematic description of a class of uncertain nonlinear large scale systems based on some practical application is given. A designing method to construct observers for such kind of nonlinear composite systems is developed. The unknown parameters and disturbances are assumed to be neither linear nor matched. A numerical example is used to illustrate the efficiency of our results. 展开更多
关键词 nonlinear large scale systems uncertainty observer design
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ON DECENTRALIZED OBSERVATION AND DECENTRALIZED CONTROL OF LARGE SCALE SYSTEMS
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作者 蔚润义 高为炳 《Acta Mathematica Scientia》 SCIE CSCD 1991年第2期136-141,共6页
In this paper, the problem of decentralized observation and decentralized control of linear, time-invariant large scale systems is studied. Based on conventional observer theory, the necessary and sufficient condition... In this paper, the problem of decentralized observation and decentralized control of linear, time-invariant large scale systems is studied. Based on conventional observer theory, the necessary and sufficient conditions for existence of completely decentralized observer are obtained. Moreover, the necessary and sufficient condition is given for stabilization of large scale systems by local output with state of the subsystem estimated through the completely decentralized observer. 展开更多
关键词 ON DECENTRALIZED OBSERVATION AND DECENTRALIZED CONTROL OF large scale systemS
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MULTITASK SCHEDULING IN NETWORKED CONTROL SYSTEMS WITH APPLICATION TO LARGE SCALE VEHICLE CONTROL
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作者 YANG Liman LI Yunhua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第1期69-72,共4页
Aiming at scheduling problems of networked control system (NCS) used to fulfill motion synthesis and cooperation control of the distributed multi-mechatronic systems, the differences of network scheduling and task s... Aiming at scheduling problems of networked control system (NCS) used to fulfill motion synthesis and cooperation control of the distributed multi-mechatronic systems, the differences of network scheduling and task scheduling are compared, and the mathematic description of task scheduling is presented. A performance index function of task scheduling of NCS according to task balance and traffic load matching principles is defined. According to this index, a static scheduling method is designed and implemented to controlling task set simulation of the DCY100 transportation vehicle. The simulation results are applied successfully to practical engineering in this case so as to validate the effectiveness of the proposed performance index and scheduling algorithm. 展开更多
关键词 Network control system(NCS) Multitask scheduling Performance index Motion synthesis large scale vehicle
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Cells grouping scheme against pilot contamination in large scale antennas system
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作者 Zhichao Zhou Yang Xiao Dong Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第3期531-540,共10页
The influence of cells groupings factor to the performance of the cells groupings time-shift pilot scheme is researched for the multiple cells large scale antennas systems(LSAS). The former researches have confirmed... The influence of cells groupings factor to the performance of the cells groupings time-shift pilot scheme is researched for the multiple cells large scale antennas systems(LSAS). The former researches have confirmed that the cells groupings time-shift pilots scheme is effective to reduce inter-cell interference, especially pilot contamination, which results from the pilot reuse in adjacent cells. However, they have not specified reasonable cells groupings factor, which plays a critical role in the general performance of the LSAS. Therefore, this problem is researched in details. The time for reverse-link data transmission will be compressed, when the groupings factor surpasses a certain range. Thus it is not always beneficial to increase the cells groupings factor without limitation. Furthermore,a reasonable cells groupings factor is deduced from the perspective of optimization to enhance the system performance. Simulations verify the proposed cell grouping factor. 展开更多
关键词 large scale antenna system multiple cells inter-cell interference time-shift pilots scheme cells grouping factor system performance
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Novel process for large scale synthesis of N-(4-hydroxyphenyl) retinamide 被引量:1
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作者 吴晓晴 余佳 吉民 《Journal of Southeast University(English Edition)》 EI CAS 2008年第2期247-249,共3页
A method to synthesize anticancer drug N-( 4- hydroxyphenyl) retinamide (4-HPR)on a large scale is described. It consists of the preferred steps of reacting all-trans retinoic acid with thionyl chloride to form re... A method to synthesize anticancer drug N-( 4- hydroxyphenyl) retinamide (4-HPR)on a large scale is described. It consists of the preferred steps of reacting all-trans retinoic acid with thionyl chloride to form retinoyl chloride and then reacting with triethylamine to generate retinoyl ammonium salt which in turn is reacted with p-aminophenol to eventually produce 4-HPR. This process can overcome many scale-up challenges that exist in the methods reported in the literature and provide an easy, mild and high yield route for large scale synthesis of 4-HPR. Moreover, the effects of the molar ratios of the reagents on the yield are examined. The best molar ratios are a 2.0 molar equivalence of thionyl chloride and a 3.0 molar equivalence of paminophenol to retinoic acid, and the total yield is 80. 7%. 展开更多
关键词 4-HPR large scale SYNTHESIS ANTICANCER
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NEW LIMITED MEMORY SYMMETRIC RANK ONE ALGORITHM FOR LARGE-SCALE UNCONSTRAINED OPTIMIZATION
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作者 刘浩 倪勤 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第3期235-239,共5页
A new limited memory symmetric rank one algorithm is proposed. It combines a modified self-scaled symmetric rank one (SSR1) update with the limited memory and nonmonotone line search technique. In this algorithm, th... A new limited memory symmetric rank one algorithm is proposed. It combines a modified self-scaled symmetric rank one (SSR1) update with the limited memory and nonmonotone line search technique. In this algorithm, the descent search direction is generated by inverse limited memory SSR1 update, thus simplifying the computation. Numerical comparison of the algorithm and the famous limited memory BFGS algorithm is given. Comparison results indicate that the new algorithm can process a kind of large-scale unconstrained optimization problems. 展开更多
关键词 optimization large scale systems symmetric rank one update nonmonotone line search limitedmemory algorithm
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Compact Scanning Tunneling Microscope with Large Scale Searching Capability for Mmultidisciplinary Applications
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作者 孟文杰 王琦 +2 位作者 张晶 侯玉斌 陆轻铀 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第5期523-526,I0001,共5页
We present the design and performance of a home-built scanning tunneling microscope (STM), which is compact (66 mm tall and 25 mm in diameter), yet equipped with a 3D atomic precision piezoelectric motor in which ... We present the design and performance of a home-built scanning tunneling microscope (STM), which is compact (66 mm tall and 25 mm in diameter), yet equipped with a 3D atomic precision piezoelectric motor in which the Z coarse approach relies on a high simplic-ity friction-type walker (of our own invention) driven by an axially cut piezoelectric tube. The walker is vertically inserted in a piezoelectric scanner tube (PST) with its brim laying at on the PST end as the inertial slider (driven by the PST) for the XZ (sample plane) motion. The STM is designed to be capable of searching rare microscopic targets (defects, dopants, boundaries, nano-devices, etc.) in a macroscopic sample area (square millimeters) under extreme conditions (low temperatures, strong magnetic elds, etc.) in which it ts. It gives good atomic resolution images after scanning a highly oriented pyrolytic graphite sample in air at room temperature. 展开更多
关键词 Scanning tunneling microscope large scale searching Air STM Electrochemical STM
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Local and global approaches of affinity propagation clustering for large scale data 被引量:15
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作者 Ding-yin XIA Fei WU +1 位作者 Xu-qing ZHAN Yue-ting ZHUANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1373-1381,共9页
Recently a new clustering algorithm called 'affinity propagation' (AP) has been proposed, which efficiently clustered sparsely related data by passing messages between data points. However, we want to cluster ... Recently a new clustering algorithm called 'affinity propagation' (AP) has been proposed, which efficiently clustered sparsely related data by passing messages between data points. However, we want to cluster large scale data where the similarities are not sparse in many cases. This paper presents two variants of AP for grouping large scale data with a dense similarity matrix. The local approach is partition affinity propagation (PAP) and the global method is landmark affinity propagation (LAP). PAP passes messages in the subsets of data first and then merges them as the number of initial step of iterations; it can effectively reduce the number of iterations of clustering. LAP passes messages between the landmark data points first and then clusters non-landmark data points; it is a large global approximation method to speed up clustering. Experiments are conducted on many datasets, such as random data points, manifold subspaces, images of faces and Chinese calligraphy, and the results demonstrate that the two ap-proaches are feasible and practicable. 展开更多
关键词 CLUSTERING Affinity propagation large scale data Partition affinity propagation Landmark affinity propagation
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Large Scale Aspects of India-China Summer Monsoon Rainfall 被引量:17
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作者 R. H. Kripalani S. V. Singh 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1993年第1期71-84,共14页
This study investigates the dominant modes of variability in monthly and seasonal rainfall over the India-China region mainly through Empirical Orthogonal Function (EOF) analysis. The EOFs have shown that whereas the ... This study investigates the dominant modes of variability in monthly and seasonal rainfall over the India-China region mainly through Empirical Orthogonal Function (EOF) analysis. The EOFs have shown that whereas the rainfall over India varies as one coherent zone, that over China varies in east-west oriented bands. The influence of this banded structure extends well into India.Relationship of rainfall with large scale parameters such as the subtropical ridge over the Indian and the western Pacific regions, Southern Oscillation, the Northern Hemispheric surface air temperature and stratospheric winds have also been investigated. These results show that the rainfall over the area around 40°N, 110°E over China is highly related with rainfall over India. The subtropical ridge over the Indian region is an important predictor over India as well an over the northern China region. ' 展开更多
关键词 OVER In large scale Aspects of India-China Summer Monsoon Rainfall EOF
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Large Scale VLSI Module Placement Using LFF Heuristics by Stages
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作者 魏少俊 董社勤 +1 位作者 洪先龙 吴有亮 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第5期812-818,共7页
We present a deterministic algorithm for large-scale VLSI module placement. Following the less flexibility first (LFF) principle,we simulate a manual packing process in which the concept of placement by stages is in... We present a deterministic algorithm for large-scale VLSI module placement. Following the less flexibility first (LFF) principle,we simulate a manual packing process in which the concept of placement by stages is introduced to reduce the overall evaluation complexity. The complexity of the proposed algorithm is (N1 + N2 ) × O( n^2 ) + N3× O(n^4lgn) ,where N1, N2 ,and N3 denote the number of modules in each stage, N1 + N2 + N3 = n, and N3〈〈 n. This complexity is much less than the original time complexity of O(n^5lgn). Experimental results indicate that this approach is quite promising. 展开更多
关键词 FLOORPLANNING placements large scale LFF principle deterministic placement algorithm
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Comparing the reinforcement capacity of welded steel mesh and a thin spray-on liner using large scale laboratory tests 被引量:7
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作者 Zhenjun Shan Porter Ian +1 位作者 Nemcik Jan Baafi Ernest 《International Journal of Mining Science and Technology》 SCIE EI 2014年第3期373-377,共5页
Steel mesh is used as a passive skin confinement medium to supplement the active support provided by rock bolts for roof and rib control in underground coal mines. Thin spray-on liners(TSL) are believed to have the po... Steel mesh is used as a passive skin confinement medium to supplement the active support provided by rock bolts for roof and rib control in underground coal mines. Thin spray-on liners(TSL) are believed to have the potential to take the place of steel mesh as the skin confinement medium in underground mines.To confirm this belief, large scale laboratory experiments were conducted to compare the behaviour of welded steel mesh and a TSL, when used in conjunction with rock bolts, in reinforcing strata with weak bedding planes and strata prone to guttering, two common rock conditions which exist in coal mines. It was found that while the peak load taken by the simulated rock mass with weak bedding planes acting as the control sample(no skin confinement) was 2494 kN, the corresponding value of the sample with 5 mm thick TSL reinforcement reached 2856 kN. The peak load of the steel mesh reinforced sample was only2321 kN, but this was attributed to the fact that one of the rock bolts broke during the test. The TSL reinforced sample had a similar post-yield behaviour as the steel mesh reinforced one. The results of the large scale guttering test indicated that a TSL is better than steel mesh in restricting rock movement and thus inhibiting the formation of gutters in the roof. 展开更多
关键词 Steel mesh Thin spray-on liners large scale laboratory experiments Strata with weak bedding planes Strata prone to guttering
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Large scale classification with local diversity AdaBoost SVM algorithm 被引量:5
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作者 Chang Tiantian Liu Hongwei Zhou Shuisheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第6期1344-1350,共7页
Local diversity AdaBoost support vector machine(LDAB-SVM) is proposed for large scale dataset classification problems.The training dataset is split into several blocks firstly, and some models based on these dataset... Local diversity AdaBoost support vector machine(LDAB-SVM) is proposed for large scale dataset classification problems.The training dataset is split into several blocks firstly, and some models based on these dataset blocks are built.In order to obtain a better performance, AdaBoost is used in each model building.In the boosting iteration step, the component learners which have higher diversity and accuracy are collected via the kernel parameters adjusting.Then the local models via voting method are integrated.The experimental study shows that LDAB-SVM can deal with large scale dataset efficiently without reducing the performance of the classifier. 展开更多
关键词 ensemble learning large scale data support vector machine ADABOOST DIVERSITY local.
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Large Scale Perturbations in Extratropical Atmosphere-Part Ⅰ: On Rossby Waves 被引量:3
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作者 Y. L. McHall 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1993年第2期169-180,共12页
This study reexamines the propagation mechanism and geostrophic property of the classical two-dimensional Rossby waves in a non-divergent barotropic atmosphere. It will be found that propagation of large scale atmosph... This study reexamines the propagation mechanism and geostrophic property of the classical two-dimensional Rossby waves in a non-divergent barotropic atmosphere. It will be found that propagation of large scale atmospheric waves depends crucially on horizontal divergence. A small Rossby number in Rossby waves is not sufficient for the waves to have a small ageostrophic component, because the two-dimensional classical Rossby waves do not manifest the geostrophic balance as good as observed in the atmosphere. 展开更多
关键词 TH large scale Perturbations in Extratropical Atmosphere-Part On Rossby Waves
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Large-Scale Synthesis of Porous Bi2O3 with Oxygen Vacancies for Efficient Photodegradation of Methylene Blue 被引量:2
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作者 Li-rong Wang Ting-ting Hou +5 位作者 Yue Xin Wen-kun Zhu Shu-yi Yu Zi-cheng Xie Shu-quan Liang Liang-bing Wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第4期500-506,I0002,共8页
Photocatalytic degradation of organic pollutants has become a hot research topic because of its low energy consumption and environmental-friendly characteristics.Bismuth oxide(Bi2O3)nanocrystals with a bandgap ranging... Photocatalytic degradation of organic pollutants has become a hot research topic because of its low energy consumption and environmental-friendly characteristics.Bismuth oxide(Bi2O3)nanocrystals with a bandgap ranging from 2.0 eV to 2.8 eV have attracted increasing attention due to high activity of photodegradation of organic pollutants by utilizing visible light.Though several methods have been developed to prepare Bi2O3-based semiconductor materials over recent years,it is still difficult to prepare highly active Bi2O3 catalysts in large scale with a simple method.Therefore,developing simple and feasible methods for the preparation of Bi2O3 nanocrystals in large scale is important for the potential applications in industrial wastewater treatment.In this work,we successfully prepared porous Bi2O3 in large scale via etching commercial Bi Sn powders,followed by thermal treatment with air.The acquired porous Bi2O3 exhibited excellent activity and stability in photocatalytic degradation of methylene blue.Further investigation of the mechanism witnessed that the suitable band structure of porous Bi2O3 allowed the generation of reactive oxygen species,such as O2^-·and·OH,which effectively degraded MB. 展开更多
关键词 Bi2O3 photocatalyst Photocatalytic degradation large scale Visible light PHOTOCATALYSIS
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Large Scale Perturbations in Extratropical Atmosphere-Part Ⅱ: On Geostrophic Waves 被引量:2
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作者 Y.L. McHall 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1993年第2期181-192,共12页
We have examined, in Part Ⅰ, the propagation mechanism and geostrophic property of classical Rossby waves in a non-divergent barotropic atmosphere. As we found that the non-divergent Rossby waves do not propagate in ... We have examined, in Part Ⅰ, the propagation mechanism and geostrophic property of classical Rossby waves in a non-divergent barotropic atmosphere. As we found that the non-divergent Rossby waves do not propagate in a hydrostatically equilibrium atmosphere, and do not manifest a good geostrophic property, an alternative large scale circulation pattern of geostrophic waves has been proposed (McHall, 1991a). The propagation mechanism and geostrophic property of these waves are examined in the present study. 展开更多
关键词 On Geostrophic Waves large scale Perturbations in Extratropical Atmosphere-Part
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