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Geological Environmental Adaptability of Qingdao Rural Urbanization Based on Fuzzy Mathematical Method 被引量:1
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作者 HOU Xin-wen YIN Zhi-xuan +4 位作者 ZHANG Jian-wei YUAN Xi-long YIN Ming-quan LI Qing-ping DONG Jie 《Asian Agricultural Research》 2010年第6期56-59,共4页
Fuzzy mathematics comprehensive evaluation method is used to evaluate the geological environment suitability of rural urbanization in Qingdao City,China.A total of 5 first-level evaluation factors are selected,includi... Fuzzy mathematics comprehensive evaluation method is used to evaluate the geological environment suitability of rural urbanization in Qingdao City,China.A total of 5 first-level evaluation factors are selected,including environmental geological condition,geological resources,engineering geological condition,geological disaster and environmental geological problem,and human engineering activity.And there are 27 second-level evaluation factors,such as topography,land type and vegetation,nature reserve,water source protection area,groundwater quality division,and major engineering project.Qingdao City is divided into four districts of suitable area,relatively suitable area,moderately suitable area and relatively unsuitable area of ecological environment.And their characteristics are introduced.Suggestions for the developing direction of urban construction are put forward.Region of Laoshan District lying to the west of the Shilaoren is suitable to set up high-rise building;west Hongshiya may establish a waste landfill site;Jiaozhou Bay,the downstream of Dagu River,and Jihongtan Reservoir should be built as the key geological environment protection area and water source protection area.And the north Hongdao should be strictly monitored in order to control the expansion of urban construction to Jihongtan Reservoir.Mocheng District and the area north of it,Jiaozhou District and the area east of it are the ideal urban construction development areas in Qingdao City in the future. 展开更多
关键词 Rural urbanization Qingdao Fuzzy mathematical method Geological environment ADAPTABILITY China
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Retrieval of Outgoing Longwave Radiation from COMS Narrowband Infrared Imagery 被引量:1
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作者 Myung-Sook PARK Chang-Hoi HO +1 位作者 Heeje CHO Yong-Sang CHOI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第3期375-388,共14页
Hourly outgoing longwave radiation (OLR) from the geostationary satellite Communication Oceanography Meteorological Satellite (COMS) has been retrieved since June 2010.The COMS OLR retrieval algorithms are based o... Hourly outgoing longwave radiation (OLR) from the geostationary satellite Communication Oceanography Meteorological Satellite (COMS) has been retrieved since June 2010.The COMS OLR retrieval algorithms are based on regression analyses of radiative transfer simulations for spectral functions of COMS infrared channels.This study documents the accuracies of OLRs for future climate applications by making an intercomparison of four OLRs from one single-channel algorithm (OLR12.0 using the 12.0 μm channel) and three multiple-channel algorithms (OLR10.8+12.0 using the 10.8 and 12.0 pm channels; OLR6.7+10.8 using the 6.7 and 10.8 μm channels; and OLRAll using the 6.7,10.8,and 12.0 μm channels).The COMS OLRs from these algorithms were validated with direct measurements of OLR from a broadband radiometer of the Clouds and Earth's Radiant Energy System (CERES) over the full COMS field of view [roughly (50°S-50°N,70°-170°E)] during April 2011.Validation results show that the root-mean-square errors of COMS OLRs are 5-7 W m-2,which indicates good agreement with CERES OLR over the vast domain.OLR6.7+10.8 and OLRAll have much smaller errors (~ 6 W m-2) than OLR12.0 and OLR10.8+12.0 (~ 8 W m-2).Moreover,the small errors of OLR6.7+10.8 and OLRAll are systematic and can be readily reduced through additional mean bias correction and/or radiance calibration.These results indicate a noteworthy role of the 6.7 μm water vapor absorption channel in improving the accuracy of the OLRs.The dependence of the accuracy of COMS OLRs on various surface,atmospheric,and observational conditions is also discussed. 展开更多
关键词 outgoing longwave radiation Communication Oceanography and Meteorological Satellite Cloud and Earth's Radiant Energy System
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Suppression of gold nanoparticle agglomeration and its separation via nylon membranes
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作者 Ayyavoo Jayalakshmi In-Chul Kim Young-Nam Kwon 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第7期931-937,共7页
Use of ultraporous nylon membrane is one of the most widely employed techniques for removal of hard and soft nanoparticles in the semiconductor industry, and the accurate determination of membrane pore size is necessa... Use of ultraporous nylon membrane is one of the most widely employed techniques for removal of hard and soft nanoparticles in the semiconductor industry, and the accurate determination of membrane pore size is necessary in order to avoid manufacturing defects caused by contamination. The gold nanoparticle has several benefits for the evaluation of polymeric membranes; however, the nanoparticles agglomerate easily on the nylon membrane and make it difficult to evaluate the membrane precisely. The properties of 2-amino-2-hydroxymethyl-1,3-propanediol(ADP) ligand in gold nanoparticle solution were systematically investigated, and ADP was utilized for improved evaluation of the nylon membranes. Nylon membrane used in this study was prepared by phase inversion techniques. Ultrathin dense layer on top of the membrane surface and Darcy structures in the microporous membrane support were observed. The gold particle rejection was carried out at various p H values from 4 to14 and higher rejection was observed at p H 4 and 8. The suppression of gold colloid agglomeration using ADP and monodispersity of gold colloids was also analyzed by confocal laser scanning microscopy(CLSM), transmission electron microscopy(TEM), and scanning electron microscopy(SEM). van der Waals interaction energy of the particles was reduced in the addition of ADP. The presence of ADP ligand in the gold solutions prevented the agglomeration of gold nanoparticles and reduced the adsorption of the particles on the nylon membrane surface,leading to precise evaluation of membrane pore sizes. 展开更多
关键词 纳米金粒子 尼龙膜 膜分离 共聚焦激光扫描显微镜 金纳米颗粒 透射电子显微镜 扫描电子显微镜 半导体工业
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Enhanced thermoelectric performance of TiO_2-based hybrid materials by incorporating conducting polymer
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作者 吴子华 谢华清 +2 位作者 翟永彪 甘良华 刘俊 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第3期214-217,共4页
In order to study the thermoelectric properties of TiO2-based hybrid materials, TiO2/polyparaphenylene(PPP)nanocomposites are fabricated by spark plasma sintering(SPS). The results show that the electrical conduct... In order to study the thermoelectric properties of TiO2-based hybrid materials, TiO2/polyparaphenylene(PPP)nanocomposites are fabricated by spark plasma sintering(SPS). The results show that the electrical conductivity follow percolation theory is enhanced due to the electron transfer highway provided by the conducting PPP phase. Furthermore,the thermal conductivity is reduced due to the drastic difference of vibrational spectra between organic and inorganic components. As a result, the greatest ZT= 0.24 is obtained for Ti O2/0.75 wt% PPP sample, which is 15-fold higher than pure Ti O2(ZT= 0.016). 展开更多
关键词 THERMOELECTRIC TIO2 polyparaphenylene(PPP)
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Crystal Structure of Dimeric Units Cd_2(ncpo)_2(phen)_2(H_2O)_2 Constructed by Flexible Dicarboxylic Acid with Fluorescent Emission
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作者 杨利 于伟 +3 位作者 张同来 张建国 刘振华 吴瑞风 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第4期405-408,共4页
A dimeric coordination complex Cd2(ncpo)2(phen)2(H2O)2 was constructed by a flexible dicarboxylic acid, 2-nitro-4-carboxylphenoxyacetic acid. Its crystal structure was determined by X-ray single-crystal diffract... A dimeric coordination complex Cd2(ncpo)2(phen)2(H2O)2 was constructed by a flexible dicarboxylic acid, 2-nitro-4-carboxylphenoxyacetic acid. Its crystal structure was determined by X-ray single-crystal diffraction analysis. The crystal is of monoclinic system, space group P21/n with a = 17.2616(3), b = 12.7460(2), c = 18.4041(3) A^°, β= 94.432(1)°, C42H30Cd2N6O16, Mr = 1099.52, V = 4037.09(12)A^°^3 Dc = 1.809 g/cm^3, F(000) = 2192, μ = 1.139 cm^-1 and Z = 4. The final R = 0.0218 and wR = 0.0703 for 8288 observed reflections with I 〉 2σ(I). There are two crystallographically independent but structurally very similar molecules in the unit cell of the title complex. It is noticeable that the ligand ncpo^2- displays a good flexibility, demonstrating different modes from the rigid ligands. The luminescence property has been investigated, which shows photoluminescence at 465, 490 and 574 nm upon excitation at 320 nm in the solid state at room temperature. 展开更多
关键词 cadmium complex crystal structure flexible dicarboxylic acid FLUORESCENCE
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Interrogating the effect of decentralized biogas injection on a natural gas network
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作者 周阳 黄小美 PENG Shi-ni 《Journal of Chongqing University》 CAS 2018年第3期87-100,共14页
Biogas from renewable sources and natural gas(NG) are both high-efficient and good-quality gaseous fuels on account of their enrichment in methane. Due to the dissimilar physical properties of biogas and NG, biogas ca... Biogas from renewable sources and natural gas(NG) are both high-efficient and good-quality gaseous fuels on account of their enrichment in methane. Due to the dissimilar physical properties of biogas and NG, biogas cannot substitute NG directly without treatment and is usually used on site due to the high cost of the transportation and distribution via exclusive pipeline system. Consequently, the injection of biogas into existing NG infrastructure was proposed to address the deficiency. In this paper, the Wobbe index (WI) as well as the combustion potential (CP) were introduced for analyzing the interchangeability of an NGbiogas mixture, and a mathematical framework was put forward for modeling and simulating NG grid with a decentralized biogas injection. Results show that the maximum admissible amount of biogas in mixture was 10.5% by volume. A medium pressure network was used to interrogate the comprehensive effect of distributed biogas injection, which showed an impact on both gas quality and hydraulic regime across the grid. 展开更多
关键词 BIOGAS INTERCHANGEABILITY INJECTION gas quality hydraulic regime
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Cloud Radiative Effects and Changes Simulated by the Coupled Model Intercomparison Project Phase 5 Models
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作者 Sun-Hee SHIN Ok-Yeon KIM +1 位作者 Dongmin KIM Myong-In LEE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第7期859-876,共18页
Using 32 CMIP5(Coupled Model Intercomparison Project Phase 5) models, this study examines the veracity in the simulation of cloud amount and their radiative effects(CREs) in the historical run driven by observed e... Using 32 CMIP5(Coupled Model Intercomparison Project Phase 5) models, this study examines the veracity in the simulation of cloud amount and their radiative effects(CREs) in the historical run driven by observed external radiative forcing for 1850-2005, and their future changes in the RCP(Representative Concentration Pathway) 4.5 scenario runs for2006-2100. Validation metrics for the historical run are designed to examine the accuracy in the representation of spatial patterns for climatological mean, and annual and interannual variations of clouds and CREs. The models show large spread in the simulation of cloud amounts, specifically in the low cloud amount. The observed relationship between cloud amount and the controlling large-scale environment are also reproduced diversely by various models. Based on the validation metrics,four models-ACCESS1.0, ACCESS1.3, Had GEM2-CC, and Had GEM2-ES-are selected as best models, and the average of the four models performs more skillfully than the multimodel ensemble average.All models project global-mean SST warming at the increase of the greenhouse gases, but the magnitude varies across the simulations between 1 and 2 K, which is largely attributable to the difference in the change of cloud amount and distribution. The models that simulate more SST warming show a greater increase in the net CRE due to reduced low cloud and increased incoming shortwave radiation, particularly over the regions of marine boundary layer in the subtropics. Selected best-performing models project a significant reduction in global-mean cloud amount of about-0.99% K^-1and net radiative warming of 0.46 W m^-2K^-1, suggesting a role of positive feedback to global warming. 展开更多
关键词 warming cloud radiative historical CMIP interannual greenhouse ACCESS oceans seasonal
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Facile preparation ofα-MnO_(2)nanowires for assembling free-standing membrane with efficient Fenton-like catalytic activity
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作者 Yufei Zhen Zhiqiang Sun +5 位作者 Ziye Jia Caihong Liu Shishu Zhu Xueyan Li Wei Wang Jun Ma 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第3期240-244,共5页
Assembling MnO_(2)nanowires into macroscopic membrane is a promising engineered technology for catalyst separation and enhancement of Fenton-like reaction activity,yet its development is limited by the deficiencies in... Assembling MnO_(2)nanowires into macroscopic membrane is a promising engineered technology for catalyst separation and enhancement of Fenton-like reaction activity,yet its development is limited by the deficiencies in preparation and property modulation of the MnO_(2)nanowires.In this work,we developed a facile method using C_(2)H_5OH and CH_(3)COOK as reductive and vital control reagents to react with KMnO_(4)by hydrothermal reaction at 140℃for 12 h,to prepare the ultralongα-MnO_(2)nanowires up to tens of micrometers with high purity and aspect ratio.Such strategy not only had the advantages of being mild,easily controlled and environmental pollution-free,but also endowedα-MnO_(2)nanowires with excellent ability as a Fenton catalyst when assembled into free-standing membrane for degrading phenolic compounds(k_(obs)=0.0738~0.1695 min^(-1))in a continuous flow reaction.The reactive oxygen species(i.e.,~·OH)from Fenton-like reaction were enriched within thisα-MnO_(2)nanowire membrane via nanoconfinement effect,which further enhanced the mass transportation of~·OH available for phenolic contaminants.MnO_(2)nanowire membrane using our method possessed the high practical potential for water purify due to its easy-preparation and enhanced catalytic performances. 展开更多
关键词 α-MnO_(2)nanowires Formation mechanism Free-standing membrane Fenton-like system
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Preparation and Thermal Properties of Grafted CNTs Composites 被引量:4
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作者 Jifen Wang Huaqing Xie Zhong Xin 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2011年第3期233-238,共6页
Oleylamine (G18) and octanol (G8) were grafted onto the surfaces of the multi-walled carbon nanotubes (CNTs). The grafted CNTs were dispersed into palmitic acid (PA) and paraffin wax (PW) to prepare phase ch... Oleylamine (G18) and octanol (G8) were grafted onto the surfaces of the multi-walled carbon nanotubes (CNTs). The grafted CNTs were dispersed into palmitic acid (PA) and paraffin wax (PW) to prepare phase change composites. The heat storage/retrieval experiments showed that the composites kept stable after repeating melting and solidification for 80 times. The structure of the G18-CNT/PA and G8-CNT/PA was homogenous compared with the pristine CNT (P-CNT)/PA. The latent heat capacity (Ls) of solid liquid phase change of G18-CNT/PW was higher than that of PW while those of the G8-CNTI/PW and P-CNT/PW were lower than that of PW. Compared with PA, all PA based composites with both P-CNTs and grafted CNTs decreased Ls evidently. The Ls values of GI8-CNT composites in both matrices were higher than that of the counterparts of G8-CNT. The thermal conductivities of all the PA based composites in the study were higher than that of PA, as well as those of all the PW based composites. However, the thermal conductivities of the GI8-CNT composites in both matrixes were lower than those of the G8-CNT composites in both matrixes at all measured temperatures. 展开更多
关键词 Carbon nanotube (CNT) GRAFTING Phase change composite Thermal property
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Experimental investigation on thermal conductivity and viscosity of aluminum nitride nanofluid 被引量:9
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作者 Wei Yu Huaqing Xie Yang Li Lifei Chen 《Particuology》 SCIE EI CAS CSCD 2011年第2期187-191,共5页
Aluminum nitride nanoparticles (AINs) have been found to be a good additive for enhancing the thermal conductivity of traditional heat exchange fluids. At a volume fraction of 0.1, the thermal conductivity enhanceme... Aluminum nitride nanoparticles (AINs) have been found to be a good additive for enhancing the thermal conductivity of traditional heat exchange fluids. At a volume fraction of 0.1, the thermal conductivity enhancement ratios are 38.71% and 40.2%, respectively, for ethylene glycol and propylene glycol as the base fluids. Temperature does not have much influence on the enhanced thermal conductivity ratios of the nanofluids, though a volume fraction of 5.0% appears to signify a critical concentration for rheology: for 〈5.0vo1% for Newtonian behavior, and for 〉5.0vo1% for obvious shear-shinning behavior, for both ethylene glycol and propylene glycol. 展开更多
关键词 NanofluidAluminum nitrideThermal conductivityViscosity
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Magnetic evidence for heavy metal pollution of topsoil in Shanghai, China 被引量:5
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作者 Guan WANG Yuan LIU +4 位作者 Jiao CHEN Feifan REN Yuying CHEN Fangzhou YE Weiguo ZHANG 《Frontiers of Earth Science》 SCIE CAS CSCD 2018年第1期125-133,共9页
This study presents the results obtained from magnetic susceptibility and heavy metal (Cu, Zn, Pb, and Cr) concentration measurements of soil profiles collected from arable land and urban parks in Baoshan District, ... This study presents the results obtained from magnetic susceptibility and heavy metal (Cu, Zn, Pb, and Cr) concentration measurements of soil profiles collected from arable land and urban parks in Baoshan District, an industrial district of Shanghai, China. The study focuses on the investigation of vertical variations in magnetic susceptibilities and heavy metal concentrations and on correlations between magnetic susceptibilities and heavy metal concentrations in soil profiles. The results demon- strate that magnetic enhancement in the surface layer of the soil profile is associated with increased heavy metal pollution. The enrichment factors (EF) and the Tomlinson Pollution Load Index (PLI-EF) are calculated for estimat- ing the level of heavy metal pollution of soil profiles in the study. The significant positive correlations between heavy metal contents, enrichment factors (EF), Tomlinson pollution load index (PLI-CF), modified Tomlinson pollution load index (PLI-EF), and magnetic susceptibility (X) indicate that much of the heavy metal contamination in the study area is linked to combustion derived particulate emissions. The results confirm that the combined magnetic measurement and heavy metal concentration analysis could provide useful information for soil monitoring in urban environments. However, the use of magnetic technique to locate the heavy metal pollution boundary in the soil profile of this studied area should be confirmed by further geochemical analysis. 展开更多
关键词 SOIL POLLUTION magnetic susceptibility heavymetals SHANGHAI
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Absolute dominance of hydrogenotrophic methanogens in full-scale anaerobic sewage sludge digesters 被引量:2
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作者 Jaai Kim Woong Kim Changsoo Lee 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2013年第11期2272-2280,共9页
Anaerobic digestion (AD) is gaining increasing attention due to the ability to covert organic pollutants into energy-rich biogas and, accordingly, growing interest is paid to the microbial ecology of AD systems. Des... Anaerobic digestion (AD) is gaining increasing attention due to the ability to covert organic pollutants into energy-rich biogas and, accordingly, growing interest is paid to the microbial ecology of AD systems. Despite extensive efforts, AD microbial ecology is still limitedly understood, especially due to the lack of quantitative information on the structures and dynamics of AD microbial communities. Such knowledge gap is particularly pronounced in sewage sludge AD processes although treating sewage sludge is among the major practical applications of AD. Therefore, we examined the microbial communities in three full-scale sewage sludge digesters using qualitative and quantitative molecular techniques in combination: denaturing gradient gel electrophoresis (DGGE) and real-time polymerase chain reaction (PCR). Eight out of eleven bacterial sequences retrieved from the DGGE analysis were not affiliated to any known species while all eleven archaeal sequences were assigned to known methanogen species. Quantitative real-time PCR analysis revealed that, based on the 16S rRNA gene abundance, the hydrogenotrophic order Methanomicrobiales is the most dominant methanogen group (〉 94% of the total methanogen population) in all digesters. This corresponds well to the prevailing occurrence of the DGGE bands related to Methanolinea and Methanospirillum, both belonging to the order Methanomicrobiales, in all sludge samples. It is therefore suggested that hydrogenotrophic methanogens, especially Methanomicrobiales strains, are likely the major players responsible for biogas production in the digesters studied. Our observation is contrary to the conventional understanding that aceticlastic methanogens generally dominate methanogen communities in stable AD environments, suggesting the need for further studies on the dominance relationship in various AD systems. 展开更多
关键词 anaerobic digestion hydrogenotrophic methanogens methanomicrobiales microbial community structure sewage sludge
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Synthesis of TiO_2 nanoparticles by propane/air turbulent flame CVD process 被引量:6
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作者 Hongyong Xie Guilan Gao Zhen Tian Naici Bing Lijun Wang 《Particuology》 SCIE EI CAS CSCD 2009年第3期204-210,共7页
Synthesis of TiO2 nanoparticles by the oxidation of titanium tetrachloride (TiCI4) in high-strength propane/air turbulent flame is investigated tentatively for mass production of TiO2 nanoparticles. Effects of react... Synthesis of TiO2 nanoparticles by the oxidation of titanium tetrachloride (TiCI4) in high-strength propane/air turbulent flame is investigated tentatively for mass production of TiO2 nanoparticles. Effects of reactor heat flux varying from 247 to 627 kJ/m^2 s, initial TiO2 number density from 2 × 10^20 to 1 × 10^21 m^ 3, and apparent residence time of TiO2 nanoparticles in reactor from 0.06 to 0.9 s, on particle morphology, phase composition, UV absorption and photoluminescence (PL) spectra are studied. The TiO2 nanoparticles synthesized, with mean size of 30-80 nm and futile mass fraction from 0.155 up to 0.575, exhibited a strong PL signal at the wavelength of 370-450 nm, with a wide peak signal at 400-420 nm, reflecting significant oxygen vacancies on the surface of the TiO2 nanoparticles. 展开更多
关键词 CVD Turbulent flame TiO2 nanoparticles PL spectra
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Prediction of effluent concentration in a wastewater treatment plant using machine learning models 被引量:4
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作者 Hong Guo Kwanho Jeong +5 位作者 Jiyeon Lim Jeongwon Jo Young Mo Kim Jong-pyo Park Joon Ha Kim Kyung Hwa Cho 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第6期90-101,共12页
Of growing amount of food waste, the integrated food waste and waste water treatment was regarded as one of the efficient modeling method. However, the load of food waste to the conventional waste treatment process mi... Of growing amount of food waste, the integrated food waste and waste water treatment was regarded as one of the efficient modeling method. However, the load of food waste to the conventional waste treatment process might lead to the high concentration of total nitrogen(T-N) impact on the effluent water quality. The objective of this study is to establish two machine learning models-artificial neural networks(ANNs) and support vector machines(SVMs), in order to predict 1-day interval T-N concentration of effluent from a wastewater treatment plant in Ulsan, Korea. Daily water quality data and meteorological data were used and the performance of both models was evaluated in terms of the coefficient of determination(R^2), Nash-Sutcliff efficiency(NSE), relative efficiency criteria(d rel). Additionally, Latin-Hypercube one-factor-at-a-time(LH-OAT) and a pattern search algorithm were applied to sensitivity analysis and model parameter optimization, respectively. Results showed that both models could be effectively applied to the 1-day interval prediction of T-N concentration of effluent. SVM model showed a higher prediction accuracy in the training stage and similar result in the validation stage.However, the sensitivity analysis demonstrated that the ANN model was a superior model for 1-day interval T-N concentration prediction in terms of the cause-and-effect relationship between T-N concentration and modeling input values to integrated food waste and waste water treatment. This study suggested the efficient and robust nonlinear time-series modeling method for an early prediction of the water quality of integrated food waste and waste water treatment process. 展开更多
关键词 Artificial neural network Support vector machine Effluent concentration Prediction accuracy Sensitivity analysis
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Photodegradation of benzene by TiO_2 nanoparticles prepared by flame CVD process 被引量:3
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作者 Hongyong Xie Luping Zhu Lingling Wang Shengwen Chen Dandan Yang Lijun Yang Guilan Gao Hao Yuan 《Particuology》 SCIE EI CAS CSCD 2011年第1期75-79,共5页
Photodegradation of benzene at ppb levels by mixed-phase TiO2 nanoparticles, synthesized by the oxidation of TiCl4 in propane/air turbulent flame chemical vapor deposition (CVD) process, is investigated experimental... Photodegradation of benzene at ppb levels by mixed-phase TiO2 nanoparticles, synthesized by the oxidation of TiCl4 in propane/air turbulent flame chemical vapor deposition (CVD) process, is investigated experimentally by using a tubular photoreactor with thin TiO2 films coated on the reactor wall by sedimentation. Effects of inlet benzene concentration from 10 to 300μg/m3, rutile mass fraction from about 20 to 50% and photoluminescence (PL) intensity of TiO2 nanoparticles on degradation degree are examined under the conditions of 70% relative humidity, 38 μg/cm2 catalyst loading, 24mW/cm2 UV irradiation of 254 nm and 5.7 s residence time in the reactor. Based on experimental results, separation of photoinduced electron (e-) and hole (h+) pairs by rutile phase is discussed as photo-induced electron (e-) in anatase phase will migrate to rutile surface due to that the potential of conductive band of rutile is lower than that of anatase, leading to more holes ready on anatase surface for oxidation reactions. 展开更多
关键词 Photodegradation Benzene TiO 2 nanoparticles Flame CVD Carrier separation Rutile/anatase phases
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Tracing the impact of stack configuration on interface resistances in reverse electrodialysis by in situ electrochemical impedance spectroscopy 被引量:1
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作者 Wenjuan Zhang Bo Han +11 位作者 Ramato Ashu Tufa Chuyang Tang Xunuo Liu Ge Zhang Jing Chang Rui Zhang Rong Mu Caihong Liu Dan Song Junjing Li Jun Ma Yufeng Zhang 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2022年第4期69-80,共12页
Reverse electrodialysis(RED)is an emerging membrane-based technology for the production of renewable energy from mixing waters with different salinities.Herein,the impact of the stack configuration on the Ohmic and no... Reverse electrodialysis(RED)is an emerging membrane-based technology for the production of renewable energy from mixing waters with different salinities.Herein,the impact of the stack configuration on the Ohmic and non-Ohmic resistances as well as the performance of RED were systematically studied by using in situ electrochemical impedance spectroscopy(EIS).Three different parameters(membrane type,number of cell pairs and spacer design)were controlled.The Ohmic and non-Ohmic resistances were evaluated for RED stacks equipped with two types of commercial membranes(Type I and Type II)supplied by Fujifilm Manufacturing Europe B.V:Type I Fuji membranes displayed higher Ohmic and non-Ohmic resistances than Type II membranes,which was mainly attributed to the difference in fixed charge density.The output power of the stack was observed to decrease with the increasing number of cell pairs mainly due to the increase in ionic shortcut currents.With the reduction in spacer thickness from 750 to 200μm,the permselectivity of membranes in the stack decreased from 0.86 to 0.79 whereas the energy efificiency losses increased from 31%to 49%.Overall,the output of the present study provides a basis for understanding the impact of stack design on internal losses during the scaling-up of RED. 展开更多
关键词 Reverse electrodialysis Electrochemical impedance spectroscopy Concentration polarization Spacer shadow effect
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Development of temperature-robust damage factor based on sensor fusion for a wind turbine structure 被引量:1
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作者 Jong-Woong PARK Sung-Han SIM +1 位作者 Jin-Hak YI Hyung-Jo JUNG 《Frontiers of Structural and Civil Engineering》 CSCD 2015年第1期42-47,共6页
Wind power systems have gained much attention due to the relatively high reliability, maturity in technology and cost competitiveness compared to other renewable alternatives. Advances have been made to increase the p... Wind power systems have gained much attention due to the relatively high reliability, maturity in technology and cost competitiveness compared to other renewable alternatives. Advances have been made to increase the power efficiency of the wind turbines while less attention has been focused on structural integrity assessment of the structural systems. Vibration-based damage detection has widely been researched to identify damages on a structure based on change in d^mmic characteristics. Widely spread methods are natural frequency-based, mode shape-based, and curvature mode shape-based methods. The natural frequency-based methods are convenient but vulnerable to environmental temperature variation which degrades damage detection capability; mode shapes are less influenced by temperature variation and able to locate damage but requires extensive sensor instrumentation which is costly and vulnerable to signal noises. This study proposes novelty of damage factor based on sensor fusion to exclude effect of temperature variation. The combined use of an accelerometer and an inclinometer was considered and damage factor was defined as a change in relationship between those two measurements. The advantages of the proposed method are: 1) requirement of small number of sensor, 2) robusmess to change in temperature and signal noise and 3) ability to roughly locate damage. Validation of the proposed method is carried out through numerical simulation on a simplified 5 MW wind turbine model. 展开更多
关键词 sensor fusion damage detection structural health monitoring
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Mass transfer between bubbles and the dense phasein gas fluidized beds
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作者 Hongyong Xie Zhiguo Sun 《Particuology》 SCIE EI CAS CSCD 2014年第5期213-217,共5页
Mass transfer between a bubble and the dense phase in gas fluidized beds of Group A and Group B particles was proposed based on previous experimental results and literature data. The mass transfer coefficient between ... Mass transfer between a bubble and the dense phase in gas fluidized beds of Group A and Group B particles was proposed based on previous experimental results and literature data. The mass transfer coefficient between bubbles and the dense phase was determined by kbe = 0.21 db. A theoretical analysis of the mass transfer coefficient between a bubble and the dense phase using diffusion equations showed that the mass transfer coefficient between a bubble and the dense phase is kbe α εmf√ub/db in both three- and two-dimensional fiuidized beds. An effective diffusion coefficient in gas fluidized beds was introduced and correlated with bubble size as De = 13.3db2.7 for Group A and Group B particles. The mass transfer coefficient kbe can then be expressed as kbe = 0.492εmf√ubdb1.7 for bubbles in a three-dimensional bed and kbe = 0.576εm√ubdb1.7 for bubbles in a two-dimensional bed. 展开更多
关键词 Fluidized bedsBubblesDense phase Mass transfer Effective diffusion coefficient
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Capture of phosphates in surface water by TiO_2 nanoparticles under UV irradiation
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作者 Hongyong Xie Qi Zheng +4 位作者 Shanzhu Wang Changwen Ma Guilan Gao Naici Bing Zhiguo Sun 《Particuology》 SCIE EI CAS CSCD 2014年第3期98-102,共5页
The capture of orthophosphates and total phosphorus from the Pudong Canal river in the Pudong District of Shanghai by TiO2 nanoparticles is studied using a rotating photoreactor and the nano-TiO2 photocatalyst Degussa... The capture of orthophosphates and total phosphorus from the Pudong Canal river in the Pudong District of Shanghai by TiO2 nanoparticles is studied using a rotating photoreactor and the nano-TiO2 photocatalyst Degussa P25. The effects of UV irradiation intensity in a range of 20-74 mW/cm^2, the loading of the TiO2 nanoparticles in a range of 0.05-0.1 g/L, irradiation time up to 4 h, and pH values in a range of 2-10.5 on the capture efficiency are investigated. The results show that the capture of orthophosphates and total P are significantly enhanced by UV irradiation; at a loading of 0.1 g/L and an irradiation intensity above 36 mW/cm^2, orthophosphates and total phosphorus are rapidly captured by TiO2 nanoparticles, causing an observed reduction from 0.4 mg/L down to 0.02 mg/L. pH values in a range of 2-10.5 have little effect on the capture efficiency of orthophosphates and total phosphorus. 展开更多
关键词 Orthophosphates Total phosphorus Surface water TiO2 nanoparticles UV irradiation
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气溶胶分布演变所引发的气候响应模态
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作者 Sarah M.Kang 谢尚平 +1 位作者 Clara Deser 向宝强 《Science Bulletin》 SCIE EI CSCD 2021年第23期2405-2411,共7页
人类活动起源的气溶胶主要分布在北半球,其引发的区域气候响应特征及动力机理仍不清楚.针对这个问题设计的理想化数值试验的结果表明,气溶胶引起的气候变化分为两个阶段:1940~1980年,全球气溶胶增多,引发向北半球输运能量的纬向平均气... 人类活动起源的气溶胶主要分布在北半球,其引发的区域气候响应特征及动力机理仍不清楚.针对这个问题设计的理想化数值试验的结果表明,气溶胶引起的气候变化分为两个阶段:1940~1980年,全球气溶胶增多,引发向北半球输运能量的纬向平均气候响应模态;1980~2020年,气溶胶强迫从西半球向东半球纬向迁移,海盆尺度的海洋-大气耦合过程变得重要,气候响应在太平洋和大西洋间呈现显著的差异.海洋动力过程会减弱纬向平均模态但加强纬向变化模态,特别是太平洋的响应在这两个阶段均呈现拉尼娜型的海温异常分布.本文揭示了气溶胶强迫引发的两个气候响应模态的差异,有利于对历史气候变化的认识和归因. 展开更多
关键词 气溶胶 历史气候变化 气候响应 耦合过程 拉尼娜 数值试验 区域气候 动力机理
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