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Infrared and Visible Image Fusion Based on Res2Net-Transformer Automatic Encoding and Decoding 被引量:2
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作者 Chunming Wu Wukai Liu Xin Ma 《Computers, Materials & Continua》 SCIE EI 2024年第4期1441-1461,共21页
A novel image fusion network framework with an autonomous encoder and decoder is suggested to increase thevisual impression of fused images by improving the quality of infrared and visible light picture fusion. The ne... A novel image fusion network framework with an autonomous encoder and decoder is suggested to increase thevisual impression of fused images by improving the quality of infrared and visible light picture fusion. The networkcomprises an encoder module, fusion layer, decoder module, and edge improvementmodule. The encoder moduleutilizes an enhanced Inception module for shallow feature extraction, then combines Res2Net and Transformerto achieve deep-level co-extraction of local and global features from the original picture. An edge enhancementmodule (EEM) is created to extract significant edge features. A modal maximum difference fusion strategy isintroduced to enhance the adaptive representation of information in various regions of the source image, therebyenhancing the contrast of the fused image. The encoder and the EEM module extract features, which are thencombined in the fusion layer to create a fused picture using the decoder. Three datasets were chosen to test thealgorithmproposed in this paper. The results of the experiments demonstrate that the network effectively preservesbackground and detail information in both infrared and visible images, yielding superior outcomes in subjectiveand objective evaluations. 展开更多
关键词 Image fusion Res2Net-Transformer infrared image visible image
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CAEFusion: A New Convolutional Autoencoder-Based Infrared and Visible Light Image Fusion Algorithm 被引量:1
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作者 Chun-Ming Wu Mei-Ling Ren +1 位作者 Jin Lei Zi-Mu Jiang 《Computers, Materials & Continua》 SCIE EI 2024年第8期2857-2872,共16页
To address the issues of incomplete information,blurred details,loss of details,and insufficient contrast in infrared and visible image fusion,an image fusion algorithm based on a convolutional autoencoder is proposed... To address the issues of incomplete information,blurred details,loss of details,and insufficient contrast in infrared and visible image fusion,an image fusion algorithm based on a convolutional autoencoder is proposed.The region attention module is meant to extract the background feature map based on the distinct properties of the background feature map and the detail feature map.A multi-scale convolution attention module is suggested to enhance the communication of feature information.At the same time,the feature transformation module is introduced to learn more robust feature representations,aiming to preserve the integrity of image information.This study uses three available datasets from TNO,FLIR,and NIR to perform thorough quantitative and qualitative trials with five additional algorithms.The methods are assessed based on four indicators:information entropy(EN),standard deviation(SD),spatial frequency(SF),and average gradient(AG).Object detection experiments were done on the M3FD dataset to further verify the algorithm’s performance in comparison with five other algorithms.The algorithm’s accuracy was evaluated using the mean average precision at a threshold of 0.5(mAP@0.5)index.Comprehensive experimental findings show that CAEFusion performs well in subjective visual and objective evaluation criteria and has promising potential in downstream object detection tasks. 展开更多
关键词 Image fusion deep learning auto-encoder(AE) INFRARED visible light
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RMPC-Based Visual Servoing for Trajectory Tracking of Quadrotor UAVs With Visibility Constraints
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作者 Qifan Yang Huiping Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第9期2027-2029,共3页
Dear Editor,This letter deals with the tracking problem of quadrotors subject to external disturbances and visibility constraints by designing a robust model predictive control(RMPC) scheme. According to the imagebase... Dear Editor,This letter deals with the tracking problem of quadrotors subject to external disturbances and visibility constraints by designing a robust model predictive control(RMPC) scheme. According to the imagebased visual servoing(IBVS) method, a virtual camera is constructed to express image moments of the tracking target. 展开更多
关键词 VISUAL IMAGE visibility
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Development of D_α band symmetrical visible optical diagnostic for boundary reconstruction on EAST tokamak
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作者 陈明 沈飊 +4 位作者 Shinichiro KADO 郭笔豪 陈大龙 蔡福瑞 肖炳甲 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期44-53,共10页
To investigate the potential of utilizing visible spectral imaging for controlling the plasma boundary shape during stable operation of plasma in future tokamak, a D_α band symmetric visible light diagnostic system w... To investigate the potential of utilizing visible spectral imaging for controlling the plasma boundary shape during stable operation of plasma in future tokamak, a D_α band symmetric visible light diagnostic system was designed and implemented on the Experimental Advanced Superconducting Tokamak(EAST). This system leverages two symmetric optics for joint plasma imaging. The optical system exhibits a spatial resolution less than 2 mm at the poloidal cross-section, distortion within the field of view below 10%, and relative illumination of 91%.The high-quality images obtained enable clear observation of both the plasma boundary position and the characteristics of components within the vacuum vessel. Following system calibration and coordinate transformation, the image coordinate boundary features are mapped to the tokamak coordinate system. Utilizing this system, the plasma boundary was reconstructed, and the resulting representation showed alignment with the EFIT(Equilibrium Fitting) results. This underscores the system's superior performance in boundary reconstruction applications and provides a diagnostic foundation for boundary shape control based on visible spectral imaging. 展开更多
关键词 visible optical diagnostic plasma boundary reconstruction EAST
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High-visibility ghost imaging with phase-controlled discrete classical light sources
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作者 仵雪滢 赵岳 李利明 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期328-334,共7页
We take phase modulation to create discrete phase-controlled sources and realize the super-bunching effect by a phasecorrelated method. From theoretical and numerical simulations, we find the space translation invaria... We take phase modulation to create discrete phase-controlled sources and realize the super-bunching effect by a phasecorrelated method. From theoretical and numerical simulations, we find the space translation invariance of the bunching effect is a key point for the ghost imaging realization. Experimentally, we create the orderly phase-correlated discrete sources which can realize high-visibility second-order ghost imaging than the result with chaotic sources. Moreover, some factors affecting the visibility of ghost image are discussed in detail. 展开更多
关键词 ghost imaging high visibility space translation invariance
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Deep learning-assisted common temperature measurement based on visible light imaging
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作者 朱佳仪 何志民 +8 位作者 黄成 曾峻 林惠川 陈福昌 余超群 李燕 张永涛 陈焕庭 蒲继雄 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期230-236,共7页
Real-time,contact-free temperature monitoring of low to medium range(30℃-150℃)has been extensively used in industry and agriculture,which is usually realized by costly infrared temperature detection methods.This pap... Real-time,contact-free temperature monitoring of low to medium range(30℃-150℃)has been extensively used in industry and agriculture,which is usually realized by costly infrared temperature detection methods.This paper proposes an alternative approach of extracting temperature information in real time from the visible light images of the monitoring target using a convolutional neural network(CNN).A mean-square error of<1.119℃was reached in the temperature measurements of low to medium range using the CNN and the visible light images.Imaging angle and imaging distance do not affect the temperature detection using visible optical images by the CNN.Moreover,the CNN has a certain illuminance generalization ability capable of detection temperature information from the images which were collected under different illuminance and were not used for training.Compared to the conventional machine learning algorithms mentioned in the recent literatures,this real-time,contact-free temperature measurement approach that does not require any further image processing operations facilitates temperature monitoring applications in the industrial and civil fields. 展开更多
关键词 convolutional neural network visible light image temperature measurement low-to-medium-range temperatures
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An organic visible-photocatalytic-adsorbence mechanism to high-efficient removal of heavy metal antimony ions
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作者 Linji Yang Ke Sun +11 位作者 Tao Liu Ciyuan Huang Libin Zhang Yang Zhou Kai Chen Shangfei Yao Ziyang Zhang Chenfu Zhao Hongxiang Zhu Bingsuo Zou Shuangfei Wang Dongfeng Xue 《Materials Reports(Energy)》 EI 2024年第3期49-59,共11页
Purification of emerging heavy metal antimony contaminated water based on advanced ingenious strategies.An activated modified coconut shell charcoal(CSC)was synthesized and evaluated as a substrate-supported loaded or... Purification of emerging heavy metal antimony contaminated water based on advanced ingenious strategies.An activated modified coconut shell charcoal(CSC)was synthesized and evaluated as a substrate-supported loaded organic photovoltaic material,PM6:PYIT:PM6-b-PYIT,to prepare a surprisingly highly efficient,stable,environmentally friendly,and recyclable organic photocatalyst(CSC–N–P.P.P),which showed excellent effects on the simultaneous removal of Sb(Ⅲ)and Sb(Ⅴ).The removal efficiency of CSC-N-P.P.P on Sb(Ⅲ)and Sb(Ⅴ)reached an amazing 99.9%in quite a short duration of 15 min.At the same time,under ppb level and indoor visible light(~1 W m^(2)),it can be treated to meet the drinking water standards set by the European Union and the U.S.National Environmental Protection Agency in 5 min,and even after 25 cycles of recycling,the efficiency is still maintained at about 80%,in addition to the removal of As(Ⅲ),Cd(Ⅱ),Cr(Ⅵ),and Pb(Ⅱ)can also be realized.The catalyst not only solves the problems of low reuse rate,difficult structure adjustment and high energy consumption of traditional photocatalysts but also has strong applicability and practical significance.The pioneering approach provides a much-needed solution strategy for removing highly toxic heavy metal antimony pollution from the environment. 展开更多
关键词 Organic photocatalyst PHOTOCATALYSIS Purification Indoor visible light
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A CSMA/CA based MAC protocol for hybrid Power-line/Visible-light communication networks:Design and analysis
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作者 Sheng Hao Huyin Zhang +2 位作者 Fei Yang Chenghao Li Jing Wang 《Digital Communications and Networks》 SCIE CSCD 2024年第2期481-497,共17页
Hybrid Power-line/Visible-light Communication(HPVC)network has been one of the most promising Cooperative Communication(CC)technologies for constructing Smart Home due to its superior communication reliability and har... Hybrid Power-line/Visible-light Communication(HPVC)network has been one of the most promising Cooperative Communication(CC)technologies for constructing Smart Home due to its superior communication reliability and hardware efficiency.Current research on HPVC networks focuses on the performance analysis and optimization of the Physical(PHY)layer,where the Power Line Communication(PLC)component only serves as the backbone to provide power to light Emitting Diode(LED)devices.So designing a Media Access Control(MAC)protocol remains a great challenge because it allows both PLC and Visible Light Communication(VLC)components to operate data transmission,i.e.,to achieve a true HPVC network CC.To solve this problem,we propose a new HPC network MAC protocol(HPVC MAC)based on Carrier Sense Multiple Access/Collision Avoidance(CSMA/CA)by combining IEEE 802.15.7 and IEEE 1901 standards.Firstly,we add an Additional Assistance(AA)layer to provide the channel selection strategies for sensor stations,so that they can complete data transmission on the selected channel via the specified CSMA/CA mechanism,respectively.Based on this,we give a detailed working principle of the HPVC MAC,followed by the construction of a joint analytical model for mathematicalmathematical validation of the HPVC MAC.In the modeling process,the impacts of PHY layer settings(including channel fading types and additive noise feature),CSMA/CA mechanisms of 802.15.7 and 1901,and practical configurations(such as traffic rate,transit buffer size)are comprehensively taken into consideration.Moreover,we prove the proposed analytical model has the solvability.Finally,through extensive simulations,we characterize the HPVC MAC performance under different system parameters and verify the correctness of the corresponding analytical model with an average error rate of 4.62%between the simulation and analytical results. 展开更多
关键词 Hybrid power-line/Visible light communication (HPVC)networks MAC protocol CSMA/CA IEEE 802.15.7 IEEE 1901 Performance analysis
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Performance Characterization of Visible Light Communication Based on GaN High-Voltage LED/PD
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作者 LU Meixin JIANG Zitong +2 位作者 FANG Li YAN Yiqun YAN Jiabin 《ZTE Communications》 2024年第4期46-52,共7页
While considerable research has been conducted on the structural principles,fabrication techniques,and photoelectric properties of high-voltage light-emitting diodes(LEDs),their performance in light communication rema... While considerable research has been conducted on the structural principles,fabrication techniques,and photoelectric properties of high-voltage light-emitting diodes(LEDs),their performance in light communication remains underexplored.A high-voltage seriesconnected LED or photodetector(HVS-LED/PD)based on the gallium nitride(GaN)integrated photoelectronic chip is presented in this paper.Multi-quantum wells(MQW)diodes with identical structures are integrated onto a single chip through wafer-scale micro-fabrication techniques and connected in series to construct the HVS-LED/PD.The advantages of the HVS-LED/PD in communication are explored by testing its performance as both a light transmitter and a PD.The series connection enhances the device's 3 dB bandwidth,allowing it to increase from 1.56 MHz to a minimum of 2.16 MHz when functioning as an LED,and from 47.42 kHz to at least 85.83 kHz when operating as a PD.The results demonstrate that the light communication performance of HVS-LED/PD is better than that of a single GaN MQW diode with bandwidth and transmission quantity,which enriches the research of GaN-based high-voltage devices. 展开更多
关键词 high-voltage LEDs high-voltage PDs GaN MQW diode array communication characterization visible light communication
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Heimtextil expands product range and makes textile interior design more visible than ever before
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《China Textile》 2024年第6期60-63,共4页
From 14 to 17 January,2025 already 2,900 exhibitors from 60 countries will present current trends,the latest collections,innovative materials and textile solutions at Heimtextil.High-calibre highlights await visitors:... From 14 to 17 January,2025 already 2,900 exhibitors from 60 countries will present current trends,the latest collections,innovative materials and textile solutions at Heimtextil.High-calibre highlights await visitors:For the first time,the Milanbased design platform Alcova will curate the Heimtextil Trends 25/26.In addition,the worldwide renowned designer and architect Patricia Urquiola brings textile design to life in the exclusive installation‘among-us’. 展开更多
关键词 interior VISIBLE TEXTILE
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紫外可见光谱结合化学模式识别对紫苏油的真伪鉴别
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作者 卞希慧 刘雨 +2 位作者 王瑶 张强 张妍 《分析测试学报》 北大核心 2025年第2期229-237,共9页
作为高经济价值且昂贵的非常规植物油,紫苏油易被低价食用油掺假。由于食用油的匀质性及其组成的复杂性,传统鉴别方法难以快速准确地鉴别紫苏油的真伪。该文探索了紫外可见光谱结合化学模式识别对紫苏油真伪鉴别的可行性。首先购买了40... 作为高经济价值且昂贵的非常规植物油,紫苏油易被低价食用油掺假。由于食用油的匀质性及其组成的复杂性,传统鉴别方法难以快速准确地鉴别紫苏油的真伪。该文探索了紫外可见光谱结合化学模式识别对紫苏油真伪鉴别的可行性。首先购买了40个纯紫苏油样品,并将大豆油、棕榈油分别按一定的比例加入到纯紫苏油中配制了51个二元掺伪和63个三元掺伪紫苏油样品。根据鉴别目的,从154个总样品中获得两个数据集,一个是由40个纯紫苏油和114个掺伪紫苏油构成的真伪紫苏油二分类数据集;另一个是由40个纯紫苏油、51个二元掺伪和63个三元掺伪紫苏油构成的真伪紫苏油三分类数据集。然后采用主成分分析(PCA)、簇类独立软模式(SIMCA)、偏最小二乘-判别分析(PLS-DA)和极限学习机(ELM)4种方法,依次对以上两个数据集进行分类。使用混淆矩阵可视化分类结果,并用准确率、精确率、召回率、F1分数对模型性能进行评价。结果表明,对于真伪紫苏油二分类和三分类数据集,PLS-DA均为最佳模型,预测准确率分别为98.04%和100%。因此,紫外可见光谱结合化学模式识别可以实现真伪紫苏油的快速准确鉴别。 展开更多
关键词 紫苏油 紫外可见光谱 化学模式识别 真伪鉴别
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见光诱导催化合成3,4-二氢异喹啉-1(2H)-酮及其衍生物
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作者 康建军 王津 陈艳 《化学研究与应用》 北大核心 2025年第1期230-236,共7页
建立了一种在温和条件下,用可见光催化合成一系列3,4-二氢异喹啉-1(2H)-酮及其衍生物的方法。该方法在室温条件下,以2-烯丙基-N-甲氧基苯甲酰胺为模板底物,以碘化钾作为光催化剂,25 W 460 nm的蓝色LED灯照射下,合成一系列3,4-二氢异喹啉... 建立了一种在温和条件下,用可见光催化合成一系列3,4-二氢异喹啉-1(2H)-酮及其衍生物的方法。该方法在室温条件下,以2-烯丙基-N-甲氧基苯甲酰胺为模板底物,以碘化钾作为光催化剂,25 W 460 nm的蓝色LED灯照射下,合成一系列3,4-二氢异喹啉-1(2H)-酮衍生物,最高产率可达到83%。该合成路径具有底物适用范围广、经济实用等特点,为3,4-二氢异喹啉-1(2H)-酮衍生物合成提供了一种经济简便的方法。 展开更多
关键词 可见光 2-烯丙基-N-甲氧基苯甲酰胺 3 4-二氢异喹啉-1(2H)-酮 异喹啉酮
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基于改进K-means算法的室内可见光通信O-OFDM系统信道均衡技术
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作者 贾科军 连江龙 +1 位作者 张常瑞 蔺莹 《电讯技术》 北大核心 2025年第1期96-102,共7页
在室内可见光通信中符号间干扰和噪声会严重影响系统性能,K均值(K-means)均衡方法可以抑制光无线信道的影响,但其复杂度较高,且在聚类边界处易出现误判。提出了改进聚类中心点的K-means(Improved Center K-means,IC-Kmeans)算法,通过随... 在室内可见光通信中符号间干扰和噪声会严重影响系统性能,K均值(K-means)均衡方法可以抑制光无线信道的影响,但其复杂度较高,且在聚类边界处易出现误判。提出了改进聚类中心点的K-means(Improved Center K-means,IC-Kmeans)算法,通过随机生成足够长的训练序列,然后将训练序列每一簇的均值作为K-means聚类中心,避免了传统K-means反复迭代寻找聚类中心。进一步,提出了基于神经网络的IC-Kmeans(Neural Network Based IC-Kmeans,NNIC-Kmeans)算法,使用反向传播神经网络将接收端二维数据映射至三维空间,以增加不同簇之间混合数据的距离,提高了分类准确性。蒙特卡罗误码率仿真表明,IC-Kmeans均衡和传统K-means算法的误码率性能相当,但可以显著降低复杂度,特别是在信噪比较小时。同时,在室内多径信道模型下,与IC-Kmeans和传统Kmeans均衡相比,NNIC-Kmeans均衡的光正交频分复用系统误码率性能最好。 展开更多
关键词 可见光通信 光正交频分复用 多径信道 信道均衡 K-means算法 反向传播神经网络
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VLC-WiFi干扰管理和服务质量驱动的跨层资源分配
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作者 刘焕淋 周会凌 +1 位作者 陈勇 黄冰川 《聊城大学学报(自然科学版)》 2025年第1期1-13,33,共14页
可见光通信(VLC)和无线保真(WiFi)组网被认为是实现未来6G移动通信的关键技术之一。为了提高室内资源分配满足业务服务质量(QoS)需求的概率,该文提出一种基于干扰管理和服务质量(QoS)驱动的跨层资源分配机制(CRAMIMQ)。该机制能根据物... 可见光通信(VLC)和无线保真(WiFi)组网被认为是实现未来6G移动通信的关键技术之一。为了提高室内资源分配满足业务服务质量(QoS)需求的概率,该文提出一种基于干扰管理和服务质量(QoS)驱动的跨层资源分配机制(CRAMIMQ)。该机制能根据物理层的信道状态与媒体访问控制层的队列状态,设计下行VLC-WiFi传输链路的自适应QoS级别评估方法和信道质量管控方法;提出基于干扰管理和QoS驱动的跨层资源分配机制以满足业务的QoS需求。仿真结果显示,相比QoS感知的跨层动态资源分配(QoS-CLDRA)方法,所提CRAMIMQ提高了业务接入成功概率,进而使最大的系统吞吐量约提高5.64%,VLC缓冲队列长度减小21.8%。 展开更多
关键词 可见光通信 异构网络 资源分配 干扰管理 服务质量
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Visibility的航空遥感相机自动焦面检测方法 被引量:6
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作者 郑丽娜 李延伟 +1 位作者 远国勤 张洋 《红外与激光工程》 EI CSCD 北大核心 2019年第4期236-241,共6页
为了解决航空遥感相机自动焦面检测的问题,提出了一种利用空间滤波测速(SFV)原理进行航空遥感相机自动焦面检测的方法。首先,在焦面检测过程中,采集线阵CCD输出图像的Visibility值,利用SFV信号的Visibility值与离焦量之间的关系,通过搜... 为了解决航空遥感相机自动焦面检测的问题,提出了一种利用空间滤波测速(SFV)原理进行航空遥感相机自动焦面检测的方法。首先,在焦面检测过程中,采集线阵CCD输出图像的Visibility值,利用SFV信号的Visibility值与离焦量之间的关系,通过搜寻SFV信号Visibility最大值找出最佳的成像焦面位置;其次,对空间滤波测速原理及Visibility与离焦量的关系进行了介绍;最后,对设计的实验装置在5~53.2 mm/s的典型像移速度下进行了20次焦面检测,结果表明最大测量误差均方值为46.25μm,小于航空遥感相机光学系统的检焦误差宽容度(76.8μm),能够满足航空遥感相机的自动焦面检测精度要求。 展开更多
关键词 SFV visibility 焦面检测 航空遥感相机
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Synthesis of C-Cl-codoped titania/attapulgite composites with enhanced visible-light photocatalytic activity 被引量:11
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作者 邓丽娟 谢毅 张高科 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期379-388,共10页
We demonstrate the synthesis of C-Cl-codoped titania/attapulgite(TiO2/ATT) composites containing a mixture of TiO2 phases by a facile sol-gel method at 70 ℃ using titanium tetraisopropoxide as the TiO2 precursor an... We demonstrate the synthesis of C-Cl-codoped titania/attapulgite(TiO2/ATT) composites containing a mixture of TiO2 phases by a facile sol-gel method at 70 ℃ using titanium tetraisopropoxide as the TiO2 precursor and ATT as a support for the TiO2 nanoparticles.The photocatalytic activity of the C-Cl-codoped TiO2/ATT composites with mixed anatase/brookite/rutile phases obtained at pH= 3.0 was much higher than that of commercially available Degussa P25 for the photocatalytic degradation of acid red G under visible-light irradiation.The excellent photocatalytic activity of the developed composite originates from the nonmetal codoping,which extends the absorption edge of TiO2 into visible region,and the presence of multiple phases,which slow the recombination of photoexcited electron/hole pairs.The formation of hydroxyl radicals during the photocatalytic degradation process was detected by photoluminescence probing using terephthalic acid.A mechanism for photocatalysis over the C-Cl-codoped TiO2/ATT composites was proposed. 展开更多
关键词 ANATASE RUTILE BROOKITE ATTAPULGITE C–Cl-codoped titania Visible light
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Preparation of spherical activated carbon-supported and Er^(3+):YAlO_3-doped TiO_2 photocatalyst for methyl orange degradation under visible light 被引量:4
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作者 董双石 张建宾 +2 位作者 高琳琳 王艳龙 周丹丹 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第10期2477-2483,共7页
In order to develop the high photocatalytic activity of TiO2 under visible light as that under ultraviolet light and make it easy to be separated from treated liquor, a visible light response and spherical activated c... In order to develop the high photocatalytic activity of TiO2 under visible light as that under ultraviolet light and make it easy to be separated from treated liquor, a visible light response and spherical activated carbon (SAC) supported photocatalyst doped with upconversion luminescence agent Er3+:YAlO3 was prepared by immobilizing Er3+:YAlO3/TiO2, which was obtained by combination of Er3+:YAlO3 and TiO2 using sol-gel method, on the surface of SAC. The crystal phase composition, surface structure and element distribution, and light absorption of the new photocatalysts were examined by X-ray diffraction (XRD), energy dispersive X-ray spectra (EDS) analysis, scanning electron microscopy (SEM) and fluorescence spectra analysis (FSA). The photocatalytic oxidation activity of the photocatalysts was also evaluated by the photodegradation of methyl orange (MO) in aqueous solution under visible light irradiation from a LED lamp (λ400 nm). The results showed that Er3+:YAlO3 could perform as the upconversion luminescence agent which converts the visible light up to ultraviolet light. The Er3+:YAlO3/TiO2 calcinated at 700 °C revealed the highest photocatalytic activity. The apparent reaction rate constant could reach 0.0197 min-1 under visible light irradiation. 展开更多
关键词 visible light upconversion luminescence TiO2 activated carbon PHOTOCATALYSIS
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Ag_3PO_4/Ag_2CO_3 p–n heterojunction composites with enhanced photocatalytic activity under visible light 被引量:10
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作者 法文君 王平 +3 位作者 岳冰 杨风岭 李大鹏 郑直 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第12期2186-2193,共8页
Formation of a p–n heterojunction rather than p-type or n-type semiconductors can enhance the separation of photogenerated electrons and holes and increase the quantum efficiency of photocatalytic reactions owing to ... Formation of a p–n heterojunction rather than p-type or n-type semiconductors can enhance the separation of photogenerated electrons and holes and increase the quantum efficiency of photocatalytic reactions owing to the difference of the electric potential in the inner electric field near the junction,pointing from n toward p. n-Ag3PO4/p-Ag2CO3 p–n heterojunction composites are prepared through a facile coprecipitation process. The obtained Ag3PO4/Ag2CO3 p–n heterojunctions exhibit excellent photocatalytic performance in the removal of rhodamine B(RhB) compared with Ag3PO4 and Ag2CO3. The 40%-Ag3PO4/Ag2CO3 composite photocatalyst(40 mol% Ag3PO4 and 60 mol% Ag2CO3) exhibits the best photocatalytic activity under visible light,demonstrating the ability to completely degrade RhB within 15 min. Transient photovoltage characterization and an active species trapping experiment further indicate that the formation of a p–n heterojunction structure can greatly enhance the separation efficiency of photogenerated carriers and produce more free h+active species,which is the predominant contributor for RhB removal. 展开更多
关键词 Silver phosphate Silver carbonate Composite catalyst p–n heterojunction Visible light Transient photovoltage
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Heterostructured BiOI@La(OH)_3 nanorods with enhanced visible light photocatalytic NO removal 被引量:6
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作者 孙艳娟 肖香 +2 位作者 董兴安 董帆 张炜 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期217-226,共10页
Heterostructured BiOI@La(OH)3 nanorod photocatalysts were prepared by a facile chemical impregnation method.The enhanced visible light absorption and charge carrier separation can be simultaneously realized after th... Heterostructured BiOI@La(OH)3 nanorod photocatalysts were prepared by a facile chemical impregnation method.The enhanced visible light absorption and charge carrier separation can be simultaneously realized after the introduction of BiOI particles into La(OH)3 nanorods.The BiOI@La(OH)3 composites were applied for visible light photocatalytic oxidization of NO in air and exhibited an enhanced activity compared with BiOI and pure La(OH)3 nanorods.The results show that the energy levels between the La(OH)3 and BiOI phases matched well with each other,thus forming a heterojunctioned BiOI@La(OH)3 structure.This band structure matching could promote the separation and transfer of photoinduced electron-hole pairs at the interface,resulting in enhanced photocatalytic performance under visible light irradiation.The photocatalytic performance of BiOI@La(OH)3 is shown to be dependent on the mass ratio of BiOI to La(OH)3.The highest photocatalytic performance can be achieved when the mass ratio of BiOI to La(OH)3 is controlled at 1.5.A further increase of the mass ratio of BiOI weakened the redox abilities of the photogenerated charge carriers.A new photocatalytic mechanism for BiOI@La(OH)3 heterostructures is proposed,which is directly related to the efficient separation of photogenerated charge carriers by the heterojunction.Importantly,the as-prepared BiOI@La(OH)3 heterostructures exhibited a high photochemical stability after multiple reaction runs.Our findings demonstrate that BiOI is an effective component for the formation of a heterostructure with the properties of a wide bandgap semiconductor,which is of great importance for extending the light absorption and photocatalytic activity of wide bandgap semiconductors into visible light region. 展开更多
关键词 Bismuth oxyiodido@lanthanide hydroxide heterostructure Nanorod Photocatalysis Visible light Nitrogen oxide removal
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Solvent-assisted synthesis of porous g-C_3N_4 with efficient visible-light photocatalvtic performance for NO removal 被引量:6
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作者 张文东 赵再望 +1 位作者 董帆 张育新 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期372-378,共7页
Graphitic carbon nitride(g-C3N4) with efficient photocatalytic activity was synthesized through thermal polymerization of thiourea with the addition of water(CN-W) or ethanol(CN-E) at 550 ℃for 2 h.The physicoch... Graphitic carbon nitride(g-C3N4) with efficient photocatalytic activity was synthesized through thermal polymerization of thiourea with the addition of water(CN-W) or ethanol(CN-E) at 550 ℃for 2 h.The physicochemical properties of the g-C3N4 were investigated by X-ray diffraction,transmission electron microscopy,ultraviolet-visible spectroscopy,photoluminescence spectroscopy,diffuse-reflection spectroscopy,BET and BJH surface area characterization,and elemental analysis.The carbon content was found to have self-doped into the g-C3N4 matrix during the thermal polymerization of thiourea and ethanol.CN-W and CN-E showed considerably enhanced visible-light photocatalytic activity,with NO removal percentages of 37.2%and 48.3%,respectively.Compared with pure g-C3N4,both the short and long lifetimes of the charge carriers in CN-W and CN-E were found to be prolonged.The mechanism of improved visible-light photocatalytic activity was deduced.The present work may provide a facile route to optimize the microstructure of g-C3N4photocatalysts for high-performance environmental and energy applications. 展开更多
关键词 Solvent-assisted Graphitic carbon nitride Visible light Photocatalytic performance Nitrogen oxide removal
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