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新乡贤文化“可见性”短视频生产研究
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作者 刘社瑞 赵钰欣 《海河传媒》 2024年第4期11-23,共13页
“可见性”包含看见和获得他人注意的双重含义,为新乡贤文化短视频传播研究提供了新思路。新乡贤文化短视频中“可见性”的生产逻辑为:多元符号运用再现新乡贤文化建设场景、媒体宏大叙事突出新乡贤文化精神内核、用户参与行为建构新乡... “可见性”包含看见和获得他人注意的双重含义,为新乡贤文化短视频传播研究提供了新思路。新乡贤文化短视频中“可见性”的生产逻辑为:多元符号运用再现新乡贤文化建设场景、媒体宏大叙事突出新乡贤文化精神内核、用户参与行为建构新乡贤文化社交空间。新乡贤文化短视频中“可见性”的效果表现为:“可见性”整体较低且具有不稳定性,不同形态的新乡贤文化“可见性”不同,“可见性”各项指标随传播效果层级加深而递减,账号运营方式、视听语言运用与“可见性”各项指标之间存在相关关系。为有效提升“可见性”,新乡贤文化短视频传播需在构建传播共同体、开展身份调适、注重情感叙事三个方面持续发力,以此助推新乡贤文化破圈与出圈。 展开更多
关键词 “可见性” 新乡贤文化 短视频 内容分析法
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“可见性”赋权——舆论是如何“可见”的? 被引量:38
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作者 姜红 开薪悦 《苏州大学学报(哲学社会科学版)》 CSSCI 北大核心 2017年第3期146-153,共8页
关于"舆论是否可能"的问题一直受到广泛争议。2013年,学者丹尼尔·戴扬(Daniel Dayan)针对当下公共空间领域发生的转向,尝试将"可见性"作为媒介研究的新路径,这种分析框架在某种程度上契合了新媒体环境下的问... 关于"舆论是否可能"的问题一直受到广泛争议。2013年,学者丹尼尔·戴扬(Daniel Dayan)针对当下公共空间领域发生的转向,尝试将"可见性"作为媒介研究的新路径,这种分析框架在某种程度上契合了新媒体环境下的问题研究。循着这样的思路去重新审度"舆论"的三个要素——主体、客体和本体,其内涵与特征也将与传统观念有所不同。在面对互联网带来的传播革命时,与其争执不休于"舆论是否可能",不如认真思考"舆论是如何‘可见’的"。 展开更多
关键词 舆论 “可见性” 公众 公共领域 社会化媒体
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家校合作中校长“可见性”低下的境况及其改善 被引量:1
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作者 秦鹏 王安全 《教学与管理》 2021年第21期49-51,共3页
作为家校合作的有力促进者,校长“可见性”制约着家校合作效果。在家校合作领导实践中,校长的“可见性”体现为身体的在场、情感的投入和行动的着陆,而“唯成绩”的办学质量评价观、校长对家长角色期望较低、校长家校合作胜任力不足是... 作为家校合作的有力促进者,校长“可见性”制约着家校合作效果。在家校合作领导实践中,校长的“可见性”体现为身体的在场、情感的投入和行动的着陆,而“唯成绩”的办学质量评价观、校长对家长角色期望较低、校长家校合作胜任力不足是造成校长“可见性”困境的主要原因。为此,营造家校合作的评价机制环境、增强校长的期望值与主动服务意识、强化校长家校合作胜任力培训是突破校长“可见性”困境的途径。 展开更多
关键词 家校合作 校长“可见性” 校长行为
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身体空间的“可见性”生产与自我认同危机——基于社交媒体语境的探索 被引量:7
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作者 郑勋 《长白学刊》 北大核心 2019年第5期149-156,共8页
近年来,社交媒体迅猛发展,特别是“媒介化社会”的出现颠覆了传统空间的建构。在社交媒体语境下,身体超越自身的空间性,以自拍照、动态图、表情图、视频、网络直播等视觉导向为主要呈现形式进行空间“可见性”生产,身体空间进而被整合... 近年来,社交媒体迅猛发展,特别是“媒介化社会”的出现颠覆了传统空间的建构。在社交媒体语境下,身体超越自身的空间性,以自拍照、动态图、表情图、视频、网络直播等视觉导向为主要呈现形式进行空间“可见性”生产,身体空间进而被整合入新的空间。同时,伴随资本的扩张,其“生产及消费”的内在逻辑让身体空间彻底地社会化。身体是自我认同的核心要素,身体空间的可见化生产深刻地影响着主体的自我认同体系。主体借助虚拟视觉符号完成的“误同”,自我呈现的多元化、碎片化,以及对自身缺乏反思并依赖他人的肯定以此获得自身存在的确认,均反映出社交媒体语境下的自我认同危机。因此,正确使用社交媒体,建构真正意义上的自我身份认同,促进网络文明建设,亟待全社会共同关注。 展开更多
关键词 身体空间 社交媒体 “可见性” 自我认同
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Facile synthesis of Ag_2O-TiO_2/sepiolite composites with enhanced visible-light photocatalytic properties 被引量:11
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作者 杜玉 汤丹丹 +1 位作者 张高科 吴晓勇 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第12期2219-2228,共10页
Ag2O-TiO 2/sepiolite heterostructure composites were synthesized by a simple two-step method at low temperatures(100–450 °C). Acid red G aqueous solution and gaseous formaldehyde were chosen as model organic p... Ag2O-TiO 2/sepiolite heterostructure composites were synthesized by a simple two-step method at low temperatures(100–450 °C). Acid red G aqueous solution and gaseous formaldehyde were chosen as model organic pollutants to evaluate the photocatalytic performance of the as-prepared composites. The results showed that the Ag2O-TiO 2/sepiolite exhibited enhanced photocatalytic activity over pure Ag2O-TiO 2,TiO 2/sepiolite,and Ag2O/sepiolite under visible-light irradiation(λ 420 nm). The excellent photocatalytic efficiency of these composites can be ascribed to the synergistic effect between the heterojunction and the porous structure of the clay layers,which induced high adsorption and efficient charge separation. In addition,the active species involved in the degradation reaction have been investigated by photoluminescence spectroscopy and quenching experiments. A possible photocatalytic degradation mechanism of acid red G dye by the Ag2O-TiO 2/sepiolite composite is also discussed. 展开更多
关键词 Silver oxide Titanium dioxide SEPIOLITE HETEROSTRUCTURE PHOTOCATALYSIS Acid red G Photocatalytic mechanism
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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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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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Substrate-dependent photoreactivities of BiOBr nanoplates prepared at different pH values 被引量:4
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作者 艾智慧 王吉玲 张礼知 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第12期2145-2154,共10页
In this study,we showed that BiO Br nanoplates prepared at different pH values have substratedependent photocatalytic activities under visible-light irradiation. The BiO Br nanoplates synthesized at pH 1(BOB-1) degr... In this study,we showed that BiO Br nanoplates prepared at different pH values have substratedependent photocatalytic activities under visible-light irradiation. The BiO Br nanoplates synthesized at pH 1(BOB-1) degraded salicylic acid more effectively than did those obtained at pH 3(BOB-3),but the order of their photocatalytic activities in rhodamine B(RhB) degradation were reversed. Electrochemical Mott–Schottky and zeta-potential measurements showed that BOB-1 had a more positive valence band and lower surface charge,leading to superior photocatalytic activity in salicylic acid degradation under visible light. However,BOB-3 was more powerful in RhB degradation because larger numbers of superoxide radicals were generated via electron injection from the excited RhB to its more negative conduction band under visible-light irradiation; this was confirmed using active oxygen species measurements and electron spin resonance analysis. This study deepens our understanding of the origins of organic-pollutant-dependent photoreactivities of semiconductors,and will help in designing highly active photocatalysts for environmental remediation. 展开更多
关键词 DEGRADATION Visible light Substrate dependent photoreactivity Bismuth oxybromide nanoplate Rhodamine B Salicylic acid
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Assessment of Coronary Stents by 64-slice Computed Tomography: In-stent Lumen Visibility and Patency 被引量:4
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作者 Ling-yan Kong Zheng-yu Jin +5 位作者 Shu-yang Zhang Zhu-hua Zhang Yi-ning Wang Lan Song Xiao-na Zhang Yun-qing Zhang 《Chinese Medical Sciences Journal》 CAS CSCD 2009年第3期156-160,共5页
Objective To assess lumen visibility of coronary stents by 64-slice computed tomography (CT) coronary angiography, and determine the value of 64-slice CT in non-invasive detecting of in-stent restenosis after coro... Objective To assess lumen visibility of coronary stents by 64-slice computed tomography (CT) coronary angiography, and determine the value of 64-slice CT in non-invasive detecting of in-stent restenosis after coronary artery stent implantation. Methods Totally, 60 patients (54 males, aged 57.0±12.7 years) and /05 stents were investigated by 64-slice CT at a mean interval of 20.0±16.6 months after coronary stents implantation. Axial multi-planar reconstruction images of the stents and curved-planar reconstruction images through the median of the stents were reconstructed for evaluating stent image quality on a 5-point scale (1=excellent, 5=nonassessable), and stent lumen diameter was detected. Conventional coronary angiography was performed in 18 patients, and 32 stents were evaluated. Results Image quality was good to excellent on average (score 1.71±0.76). Stent image quality score was correlated to heart rate (r=0. 281, P〈0.01) and stent diameter (r=-0.480, P〈0.001). All the stents were assessable in lumen visibility with an average visible lumen diameter percentage of 60.7%±13.6%. Visible lumen diameter percentage was correlated to heart rate (r=-0.193, P〈0.05), stent diameter (r=0.403, P〈0.001), and stent image quality score (r=-0.500, P〈0.001). Visible lumen diameter percentage also varied depending on the stent type. In comparison with the conventional coronary angiography, 4 of 6 in-stent stenoses were correctly detected. The sensitivity and specificity for the detection of in-stent stenosis were 66.7% and 84.6%, respectively. Conclusions Using a 64-slice CT, the stent lumen is partly visible in most of the stents. And 64-slice CT may be useful in the assessment of stent patency. 展开更多
关键词 coronary artery in-stent restenosis computed tomography
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Predictability of outcome of caustic ingestion by esophagogastroduodenoscopy in children 被引量:8
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作者 Abdulkerim Temiz Pelin Oguzkurt +2 位作者 Semire Serin Ezer Emine Ince Akgun Hicsonmez 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第10期1098-1103,共6页
AIM: To assess the necessity of esophagogastroduodenoscopy (EGD) to predict the outcome of caustic ingestion in children. METHODS: The study included 206 children who underwent EGD because of ingestion of caustic subs... AIM: To assess the necessity of esophagogastroduodenoscopy (EGD) to predict the outcome of caustic ingestion in children. METHODS: The study included 206 children who underwent EGD because of ingestion of caustic substances between January 2005 and August 2010. Retrospective analysis of data of the patients was performed. RESULTS: The male/female ratio was 1.6 and mean age was 38.1 ± 28.8 mo. The caustic substances were acidic in 72 (34.9%) cases, alkaline in 56 (27.2%), liquid household bleach in 62 (30.1%), and unknown in 16 (7.8%). Fifty-seven (27.7%) patients were symptom-free. Significant clinical findings were observed in 149 (72.3%) patients. Upper gastrointestinal endoscopy findings of esophageal injury were grade 0 in 86 (41.7%) patients, grade 1 in 49 (23.8%), grade 2a in 42 (20.4%), grade 2b in 28 (13.6%), and grade 3a in 1 (0.5%) patient. 35 patients with grade 2a, 2b, and 3a injuries underwent esophageal dilation at second week of ingestion. Esophageal stricture, which necessitated a regular dilation program developed in 13 of the aforementioned 35 patients. There is no statistically significant difference in the rate of development of esophageal stricture between the patients who ingested acidic (15.3%) and alkaline (8.9%) substances (P = 0.32). Severe gastric injury was detected in 38 (18.5%) patients. The rate of development of gastric injury was significantly higher in the acidic group (14%) than in the alkaline group (2.9%) (P = 0.001). Out of 149 patients with clinical findings, 49 (32.9%) patients had no esophageal injury and 117 (78.5%) patients had no gastric lesion. Esophageal and severe gastric injuries were detected in 20 (35.1%) and 8 (14%) of patients with no clinical findings respectively. Pyloric stenosis developed in 6 patients. Pyloric obstruction improved with balloon dilation in 2 patients. Mean hospitalization time were 1.2 ± 0.5 d for grade 0 and 2.3 ± 5 d for grade 1 and 6.3 ± 6.2 d for grade 2a and 15.8 ± 18.6 d for grade 2b. It was significantly longer for patients with grade 2a and 2b injuries (P = 0.000). CONCLUSION: Endoscopy is an effective technique for determining the presence of esophageal and gastric damage and to avoid unnecessary treatment in patients with no or mild injury. 展开更多
关键词 ENDOSCOPY CAUSTIC Injury ESOPHAGUS STOMACH
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Preparation of a fullerene[60]‐iron oxide complex for the photo‐fenton degradation of organic contaminants under visible‐light irradiation 被引量:7
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作者 Cong‐yang Zou Ze‐da Meng +4 位作者 Wen‐chao Ji Shou‐qing Liu Zhemin Shen Yuan Zhang Ni‐shan Jiang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第6期1051-1059,共9页
Iron oxide(Fe2O3) was doped onto fullerene[60](C(60)) to form a C(60)‐Fe2O3 composite using an easy and scalable impregnation method. The as‐prepared C(60)‐Fe2O3 samples were characterized by powder X‐ra... Iron oxide(Fe2O3) was doped onto fullerene[60](C(60)) to form a C(60)‐Fe2O3 composite using an easy and scalable impregnation method. The as‐prepared C(60)‐Fe2O3 samples were characterized by powder X‐ray diffraction, X‐ray photoelectron spectroscopy, scanning electron microscopy, high‐resolution transmission electron microscopy, UV‐vis absorption spectroscopy, Raman spec‐troscopy, and Fourier transform infrared spectroscopy. The photocatalytic activity of the C(60)‐Fe2O3 catalyst was evaluated by examining the degradation of methylene blue(MB), rhodamine B(RhB), methyl orange(MO), and phenol under visible light(λ 420 nm) in the presence of hydrogen per‐oxide. The results showed that the catalyst exhibited excellent catalytic properties over a wide pH range 3.06–10.34. Under optimal conditions, 98.9% discoloration and 71% mineralization of MB were achieved in 80 min. Leaching test results indicated that the leaching of iron from the catalyst was negligible and that the catalyst had a high photocatalytic activity after five reaction cycles. The catalyst was also efficient in the degradation of RhB, MO, and phenol. These findings could be at‐tributed to the synergetic effects of C(60) and Fe2O3. We used active species trapping experiments to determine the main active oxidant in the photocatalytic reaction process and found that hydroxyl radicals played a major role in the entire process. 展开更多
关键词 C60‐Fe2O3 Heterogeneousphotocatalysis Photo‐Fenton VisiblelightActive species TRAPPING
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Co-MOF as an electron donor for promoting visible-light photoactivities of g-C3N4 nanosheets for CO2 reduction 被引量:13
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作者 Qiuyu Chen Sijia Li +4 位作者 Hongyi Xu Guofeng Wang Yang Qu Peifen Zhu Dingsheng Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第3期514-523,共10页
A possible mechanism for boosting the visible-light photoactivities of graphitic carbon nitride(g-C3N4)nanosheets for CO2 reduction via coupling with the electron donor Co-metal-organic framework(MOF)is proposed in th... A possible mechanism for boosting the visible-light photoactivities of graphitic carbon nitride(g-C3N4)nanosheets for CO2 reduction via coupling with the electron donor Co-metal-organic framework(MOF)is proposed in this study.Specifically,Co-MOF as an electron donor is capable of transferring the photogenerated electrons in the lowest unoccupied molecular orbital(LUMO)to the conduction band of g-C3N4 to facilitate charge separation.As expected,the prepared Co-MOF/g-C3N4 nanocomposites display excellent visible-light-driven photocatalytic CO2 reduction activities.The CO production rate of 6.75μmol g–1 h–1 and CH4 evolution rate of 5.47μmol g–1 h–1 are obtained,which are approximately 2 times those obtained with the original g-C3N4 under the same conditions.Based on a series of analyses,it is shown that the introduction of Co-MOF not only broadens the range of visible-light absorption but also enhances the charge separation,which improves the photocatalytic activity of g-C3N4 to a higher level.In particular,the hydroxyl radical(·OH)experiment was operated under 590 nm(single-wavelength)irradiation,which further proved that the photogenerated electrons in the LUMO of Co-MOF can successfully migrate to g-C3N4.This work may provide an important strategy for the design of highly efficient g-C3N4-based photocatalysts for CO2 reduction. 展开更多
关键词 Co-MOF g-C3N4 nanosheets Charge separation Visible-light photoactivity Photocatalytic CO2 conversion
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Structural engineering of 3D hierarchical Cd0.8Zn0.2S for selective photocatalytic CO2 reduction 被引量:13
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作者 Lei Cheng Dainan Zhang +2 位作者 Yulong Liao Jiajie Fan Quanjun Xiang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第1期131-140,共10页
The solar-driven catalytic conversion of CO2 to useful chemical fuels is regarded as an environmentally friendly approach to reduce the consumption of fossil fuels and mitigate the greenhouse effect.However,it is high... The solar-driven catalytic conversion of CO2 to useful chemical fuels is regarded as an environmentally friendly approach to reduce the consumption of fossil fuels and mitigate the greenhouse effect.However,it is highly intriguing and challenging to promote the selectivity and efficiency of visible-light-responsive photocatalysts that favor the adsorption of CO2 in photoreduction processes.In this work,three-dimensional hierarchical Cd0.8Zn0.2S flowers(C8Z2S-F)with ultrathin petals were successfully synthesized through an in-situ self-assembly growth process using sodium citrate as a morphology director.The flower-like Cd0.8Zn0.2S solid solution exhibited remarkable photocatalytic performance in the reduction of CO2,generating CO up to 41.4μmol g^−1 under visible-light illumination for 3 h;this was nearly three times greater than that of Cd0.8Zn0.2S nanoparticles(C8Z2S-NP)(14.7μmol g^−1).Particularly,a comparably high selectivity of 89.9%for the conversion of CO2 to CO,with a turnover number of 39.6,was obtained from the solar-driven C8Z2S-F system in the absence of any co-catalyst or sacrificial agent.Terahertz time-domain spectroscopy indicated that the introduction of flower structures enhanced the light-harvesting capacity of C8Z2S-F.The in situ diffuse reflectance infrared Fourier transform spectroscopy unveiled the existence of surface-adsorbed species and the conversion of photoreduction intermediates during the photocatalytic process.Empirical characterizations and predictions of the photocatalytic mechanism demonstrated that the flower-like Cd0.8Zn0.2S solid solution possessed desirable CO2 adsorption properties and an enhanced charge-transfer capability,thus providing a highly effective photocatalytic reduction of CO2. 展开更多
关键词 Cd0.8Zn0.2S flowers Self-assembly growth Photocatalytic CO2 reduction High selectivity Visible-light irradiation
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Assessing the Seasonal Predictability of Summer Precipitation over the Huaihe River Basin with Multiple APCC Models 被引量:3
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作者 TANG Wei LIN Zhao-Hui LUO Li-Feng 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第4期185-190,共6页
Seasonal rainfall predictability over the Huaihe River basin is evaluated in this paper on the basis of 23-year(1981-2003) retrospective forecasts by 10 climate models from the Asia-Pacific Economic Cooperation(APEC) ... Seasonal rainfall predictability over the Huaihe River basin is evaluated in this paper on the basis of 23-year(1981-2003) retrospective forecasts by 10 climate models from the Asia-Pacific Economic Cooperation(APEC) Climate Center(APCC) multi-model ensemble(MME) prediction system.It is found that the summer rainfall variance in this basin is largely internal,which leads to lower rainfall predictability for most individual climate models.By dividing the 10 models into three categories according to their sea surface temperature(SST) boundary conditions including observed,predicted,and persistent SSTs,the MME deterministic predictive skill of summer rainfall over Huaihe River basin is investigated.It is shown that the MME is effective for increasing the current seasonal forecast skill.Further analysis shows that the MME averaged over predicted SST models has the highest rainfall prediction skill,which is closely related to model's capability in reproducing the observed dominant modes of the summer rainfall anomalies in Huaihe River basin.This result can be further ascribed to the fact that the predicted SST MME is the most effective model ensemble for capturing the relationship between the summer rainfall anomalies over Huaihe River basin and the SST anomalies(SSTAs) in equatorial oceans. 展开更多
关键词 seasonal forecast multi-model ensemble predictive skill Huaihe River basin
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Visible-Light Activities of Erbium Doped BiVO4 Photocatalysts
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作者 张爱平 张进治 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期73-78,I0002,共7页
Er-doped BiVO4 composite photocatalyst was hydrothermal synthesized and characterized by X-ray powder diffraction, scanning electron microscopy, energy-dispersive X-ray Spectroscopy, X-ray photoelectron spectroscopy, ... Er-doped BiVO4 composite photocatalyst was hydrothermal synthesized and characterized by X-ray powder diffraction, scanning electron microscopy, energy-dispersive X-ray Spectroscopy, X-ray photoelectron spectroscopy, and UV-Vis diffuse reflectance spectra techniques. The activity of the catalyst was determined by oxidative decomposition of methyl orange in aqueous solution under visible-light irradiation. X-ray photoelectron spectroscopy and energy-dispersive X-ray Spectroscopy analysis revealed that the doped Er existed in the form of Er2O3. It also showed that the Er doping can enhance the visible-light absorption abilities of catalysts and their visible-light-driven photocatalytic activities in comparison with those of pure BiVO4. 展开更多
关键词 PHOTOCATALYSIS Composite photocatalyst VISIBLE-LIGHT
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Immobilization of metal-organic molecular cage on g-C3N4 semiconductor for enhancement of photocatalytic H2 generation 被引量:1
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作者 Yuanpu Wang Liang Liu +4 位作者 DongJun Wu Jing Guo Jianying Shi Junmin Liu Chengyong Su 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第8期1198-1204,共7页
A new compound based on immobilizing of Pd6(RuL3)8(BF4)28 (L=2-(pyridin-3-yl)-1H-imidazo [4,5-f][1,10]-phenanthroline) cage (MOC-16) on g-C3N4 was synthesized. Infrared spectrum and powder X-ray diffraction were used ... A new compound based on immobilizing of Pd6(RuL3)8(BF4)28 (L=2-(pyridin-3-yl)-1H-imidazo [4,5-f][1,10]-phenanthroline) cage (MOC-16) on g-C3N4 was synthesized. Infrared spectrum and powder X-ray diffraction were used to characterize structure of hybrid MOC-16/g-C3N4, as well as UV-vis absorption spectrum and X-ray photoelectron spectroscopy were carried out to unveil photocatalytic mechanism. With the introduction of MOC-16, the absorption edge of MOC-16/g-C3N4 in UV-vis spectrum extended apparently to long-wavelength region compared with pristine g-C3N4. H2 evolution yielded with MOC-16/g-C3N4 in aqueous solution containing TEOA was much higher than that with RuL3/g-C3N4, Pd/RuL3/g-C3N4 and mixture of MOC-16 and g-C3N4, showing that the octahedral cage structure with high-efficient electron transfer and the interface interaction between MOC-16 and g-C3N4 were significant for improvement of H2 evolution. 展开更多
关键词 g-C3N4 Metal-organic cage Photocatalytic H2 evolution Visible light Stability
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In situ fabrication of CdMoO4/g-C3N4 composites with improved charge separation and photocatalytic activity under visible light irradiation 被引量:5
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作者 Bo Chai Juntao Yan +2 位作者 Guozhi Fan Guangsen Song Chunlei Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第1期170-179,共10页
To further improve the charge separation and photocatalytic activities of g-C3N4 and CdMoO4 under visible light irradiation,CdMoO4/g-C3N4 composites were rationally synthesized by a facile precipitation-calcination pr... To further improve the charge separation and photocatalytic activities of g-C3N4 and CdMoO4 under visible light irradiation,CdMoO4/g-C3N4 composites were rationally synthesized by a facile precipitation-calcination procedure.The crystal phases,morphologies,chemical compositions,textural structures,and optical properties of the as-prepared composites were characterized by the corresponding analytical techniques.The photocatalytic activities toward degradation of rhodamine B solution were evaluated under visible light irradiation.The results revealed that integrating CdMoO4 with g-C3N4 could remarkably improve the charge separation and photocatalytic activity,compared with those of pristine g-C3N4 and CdMoO4.This would be because the CdMoO4/g-C3N4 composites could facilitate the transfer and separation of the photoexcited electron-hole pairs,which was confirmed by electrochemical impedance spectroscopy,transient photocurrent responses,and photoluminescence measurements.Moreover,active species trapping experiments demonstrated that holes(h+)and superoxide radicals(?O2?)were the main active species during the photocatalytic reaction.A possible photocatalytic mechanism was proposed on the basis of the energy band structures determined by Mott-Schottky tests.This work would provide further insights into the rational fabrication of composites for organic contaminant removal. 展开更多
关键词 CdMoO4/g-C3N4 composite HETEROJUNCTION Charge separation Visible light Photocatalytic activity
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An indoor positioning system for mobile target tracking based on VLC and IMU fusion 被引量:1
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作者 Zou Qian Xia Weiwei +3 位作者 Zhang Jing Huang Bonan Yan Feng Shen Lianfeng 《Journal of Southeast University(English Edition)》 EI CAS 2018年第4期451-458,共8页
An indoor positioning system( IPS) is designed to realize positioning and tracking of mobile targets,by taking advantages of both the visible light communication( VLC) and inertial measurement unit( IMU). The platform... An indoor positioning system( IPS) is designed to realize positioning and tracking of mobile targets,by taking advantages of both the visible light communication( VLC) and inertial measurement unit( IMU). The platform of the IPS is designed,which consists of the light-emitting diode( LED)based transmitter,the receiver and the positioning server. To reduce the impact caused by measurement errors,both inertial sensing data and the received signal strength( RSS) from the VLC are calibrated. Then,a practical propagation model is established to obtain the distance between the transmitter and the receiver from the RSS measurements. Furthermore,a hybrid positioning algorithm is proposed by using the adaptive Kalman filter( AKF) and the weighted least squares( WLS)trilateration to estimate the positions of the mobile targets.Experimental results show that the developed IPS using the proposed hybrid positioning algorithm can extend the localization area of VLC,mitigate the IMU drifts and improve the positioning accuracy of mobile targets. 展开更多
关键词 indoor positioning system (IPS) visible light communication (VLC) inertial measurement unit (IMU) hybrid positioning algorithm
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MFV-Class: a multi-faceted visualization tool of object classes
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作者 张志猛 潘云鹤 庄越挺 《Journal of Zhejiang University Science》 EI CSCD 2004年第11期1374-1381,共8页
Classes are key software components in an object-oriented software system. In many industrial OO software systems, there are some classes that have complicated structure and relationships. So in the processes of softw... Classes are key software components in an object-oriented software system. In many industrial OO software systems, there are some classes that have complicated structure and relationships. So in the processes of software maintenance, testing, software reengineering, software reuse and software restructure, it is a challenge for software engineers to understand these classes thoroughly. This paper proposes a class comprehension model based on constructivist learning theory, and implements a software visualization tool (MFV-Class) to help in the comprehension of a class. The tool provides multiple views of class to uncover manifold facets of class contents. It enables visualizing three object-oriented metrics of classes to help users focus on the understanding process. A case study was conducted to evaluate our approach and the toolkit. 展开更多
关键词 Program comprehension Reverse engineering Software visualization Object-oriented software metrics Program analysis
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Thiazolo[5,4-d]thiazole-based covalent organic framework microspheres for blue light photocatalytic selective oxidation of amines with O2 被引量:1
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作者 Fulin Zhang Xia Li +2 位作者 Xiaoyun Dong Huimin Hao Xianjun Lang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第9期2395-2404,共10页
Covalent organic frameworks(COFs)with photoactive units have attracted significant interest in visible light photocatalysis and can present a metal‐free scenario for activating O_(2).As a typical photoactive unit,thi... Covalent organic frameworks(COFs)with photoactive units have attracted significant interest in visible light photocatalysis and can present a metal‐free scenario for activating O_(2).As a typical photoactive unit,thiazolo[5,4‐d]thiazole(TzTz)has rarely been added to COFs.However,circumventing the low reversibility of TzTz,it could be embedded into the building blocks beforehand,along with other bonds likeβ‐ketoenamine in forming COFs.TzTz was embedded into 1,1′‐biphenyl‐4,4′‐diamine(BD)using this approach to produce 4,4′‐(TzTz‐2,5‐diyl)dianiline(DTz).Under organobase‐modulated solvothermal conditions,combining 1,3,5‐triformylphloroglucinol(Tp)with BD and DTz resulted in the production ofβ‐ketoenamine‐linked TpBD‐COF and TpDTz‐COF.Both TpDTz‐COF and TpBD‐COF are microspheres.TpDTz‐COF possessed more adequate separation and charge migration than TpBD‐COF.This resulted in superior performance for the blue light photocatalytic selective oxidation of benzylamine with O_(2).Furthermore,with O_(2) as the main oxidant,a wealth of benzylamines could be converted into imines over TpDTz‐COF.Mechanistic investigations substantiate that oxidation of benzylamines obeys an electron transfer pathway,in which superoxide anion(O_(2)•–)is the crucial reactive oxygen species.This study highlights the superiority of TzTz‐embedded COFs in developing effective photocatalytic systems for organic transformations. 展开更多
关键词 Covalent organic framework Thiazolo[5 4-d]thiazole Visible light Photocatalysis Selective oxidation
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