检索结果-南通市图书馆

Plasmon-enhanced Performance of Dye-sensitized Solar Cells Based on Electrodeposited Ag Nanoparticles

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2014年第1期30卷 1-7页

作者： Xinning luan Ying Wang Department of Mechanical & Industrial Engineering Louisiana State University

In the present work, pulse current deposition is used to deposit evenly distributed and uniformly sized Ag nanoparticles onto a TiO2 nanotube array as photoelectrode in dye-sensitized solar cells （DSSCs）, and the size and amount of loading Ag nanoparticles are controlled by the pulse deposition time. Due to the enhanced light absorption and electron-hole separation caused by plasmon effect, DSSCs based on Ag-modified TiO2 nanotube arrays show higher energy conversion efficiencies than those based on bare nanotubes with the same tube length. Particularly, DSSC based on nanotubes modified using pulse deposition time 1 s/3 s delivers the highest energy conversion efficiency of 1.68% and the largest short-circuit current of 4.37 mA/ cm2, while DSSC consisting of bare nanotubes exhibits efficiency of 1.20% and short-circuit current of 2.27 mA/cm2, which represents a 40% enhancement of cell efficiency in DSSC based on Ag-modified Ti02 nanotubes. It is also noted that overly long pulse deposition time will not further increase DSSC efficiency due to agglomeration of Ag particles. For example, when the pulse deposition time is increased to 2 s/6 s, DSSC based on Ag-modified nanotubes exhibits a lower efficiency of 1.42%. Moreover, high-concentration TiCI4 treatment on TiO2 nanotube arrays can further increase the energy conversion efficiencies to 3.82% and 2.61% for DSSC based on Ag-modified TiO2 nanotubes and DSSC based on bare TiO2 nanotubes, respectively, by significantly creating more surface area for dye loading.

关键词： TiO2 nanotube Dye-sensitized solar cell Pulse current deposition Ag nanoparticle TiCI4 treatment

Thermal Annealing and Graphene Modification of Exfoliated Hydrogen Titanate Nanosheets for Enhanced Lithium-ion Intercalation Properties

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2014年第9期30卷 839-846页

作者： Xinning luan Ying Wang Department of Mechanical and Industrial Engineering Louisiana State UniversityBaton Rouge LA 70803 USA

Hydrogen titanate has been considered as a promising lithium intercalation material due to its unique layered structure. In the present work, we fabricate 2D graphene/hydrogen titanate hybrid nanosheets for application as anode materials in lithium-ion batteries. H2Ti307 nanosheets are synthesized by exfoliation of a layered precursor via interacting bulky tetrabutylammonium （TBA＋） cations, followed by ion exchange with Na＋ ions and washing with water. The as-prepared hydrogen titanate nanosheets are well-dispersed exhibiting ultra-thin thickness with a lateral size up to a few micrometers. The sample is then annealed at 450, 650 Rnd 850 ℃, to optimize its Li＋-intercalation property. Heating at 450 ℃ leads to well-crystallized hydrogen titanate with a trace amount of TiO2. Heating at 650 and 850 ℃ results in mixed sodium titanates, since some sodium ions in the interlayer structure cannot be washed away and become chemically bonded to [TiO6] octahedra at high temperatures. Electrochemical properties of all the four samples are then evaluated by charged/discharged for 100 electrochemical cycles at 0.01-2.5 V vs. Li＋/Li at a specific current of 170 mA g-1. The unannealed hydrogen titanate delivers the highest initial discharge capacity of 130.5 mA h g-l, higher than 124.6 mA h g-1 from hydrogen titanate annealed at 450 ℃, as well as 101.3 and 63.8 mA h g-1 from hydrogen titanate annealed at 650 and 850℃, respectively, due to the high surface area from well-dispersed unannealed nanosheets. However, after 100 electrochemical cycles, well-crystallized hydrogen titanate annealed at 450 ℃ retain the highest charge capacity of 115.2 mA h g-1, corresponding to a capacity retention of 92.5%, while unannealed hydrogen titanate exhibits a final capacity of 72.1 mA h g-1 and a capacity retention of only 55.2%. To further improve energy density of lithium-ion battery, graphene/hydrogen titanate hybrid nanosheets are fabricated by adding graphene nanosheets into hydrogen titanates

关键词： Hydrogen titanate Sodium titanate Graphene nanosheets Exfoliation process Lithium-ion battery

Modeling of turbidity dynamics caused by wind-induced waves and current in the Taihu Lake

在线全文

学校读者我要写书评

暂无评论

International Journal of Sediment Research 2013年第2期28卷 139-148页

作者： ting-feng WU Bo-qiang QIN Guang-wei ZHU Meng-yuan ZHU Wei LI Cheng-mei luan State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of Sciences Jiangsu Province Hydrology and Water Resource Investigation Bureau

A simple turbidity model was developed with a sound physical basis based on in situ high-frequency observations of short-term,strong wind-induced sediment suspension in Taihu Lake,*** validation results show that the model could successfully simulate turbidity caused by strong wind events,despite the relatively poor simulation accuracy for high values of turbidity caused by the entrainment of cyanobacteria by turbulence. The in situ observations and model simulation results indicate that the wind waves were within a narrow spectral band,with spectral energy mainly distributed within the 0.28-0.75 Hz band on opposite sides of the peak *** high-frequency and low-energy wind waves are sensitive to depth ***,the average depth of the lake is only 1.9 m,and wind waves still represent the main force of sediment suspension at the sediment-water ***,lake currents were of significance to the maintenance of background turbidity in calm waves or ripples and in the determination of critical shear *** considering the spatial distribution of hydrodynamics and sediment,the model can be used to simulate the turbidity of the entire lake as well as boundary conditions for three-dimensional numerical models.

关键词： Taihu Lake Wind-driven current Wind wave frequency spectrum Turbidity Critical shear stress Model

A review on vasohibin and ocular neovascularization

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2020年第6期13卷 1004-1008页

作者： Xiao-Nan Hu Yan Ni Jie luan yu-Zhi Ding Department of Ophthalmology Zhongda Hospital Southeast UniversityNanjing 210000Jiangsu ProvinceChina Medical School of Southeast University Nanjing 210000Jiangsu ProvinceChina

Ischemic and neovascular disease is one of the most difficult ocular diseases to deal with ***,poor visual acuity and decreased life quality are bothering patients and ophthalmologists for *** vascular endothelial growth factor(VEGF)was found to be a primary factor in promoting retinal angiogenesis,intravitreal injection of anti-VEGF drugs has been the firstline ***,some patients are refractory to this therapy and problems of economic burden,local complications and adverse effects promote researches into other possible *** vasohibin(VASH)family is a newly-investigated factor in modulating ocular *** family includes VASH1 and VASH2,which show opposite effects of inhibiting and accelerating angiogenesis *** results have been reported in cellular and animal *** further researches,it can be a promising future target of treating ocular neovascular diseases.

关键词： vasohibin ocular neovascularization retinal neovascularization

Neural network-based H∞ filtering for nonlinear systems with time-delays

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2008年第1期19卷 141-147页

作者： luan Xiaoli Liu Fei Inst. of Automation Jiangnan Univ. Wuxi 214122 P. R. China

A novel H∞ design methodology for a neural network-based nonlinear filtering scheme is addressed. Firstly, neural networks are employed to approximate the nonlinearities. Next, the nonlinear dynamic system is represented by the mode-dependent linear difference inclusion （LDI）. Finally, based on the LDI model, a neural network-based nonlinear filter （NNBNF） is developed to minimize the upper bound of H∞ gain index of the estimation error under some linear matrix inequality （LMI） constraints. Compared with the existing nonlinear filters, NNBNF is time-invariant and numerically tractable. The validity and applicability of the proposed approach are successfully demonstrated in an illustrative example.

关键词： H∞ filtering nonlinear system time-delay neural network linear matrix inequality

Rhodium-Catalyzed Asymmetric Trifluoromethoxylation of Racemic Allylic Trichloroacetimidates

在线全文

学校读者我要写书评

暂无评论

CCS Chemistry 2024年第8期6卷 1885-1894页

作者： Liyan Wang Yafeng Si yu-Xin luan Pingping Tang State Key Laboratory and Institute of Elemento-Organic Chemistry College of ChemistryNankai UniversityTianjin 300071

A rhodium/diene catalyzed asymmetric allylic trifluoromethoxylation reaction is reported,which afforded chiral trifluoromethoxylated allylic compounds in 52%–97%yields with up to 97%enantiomeric *** are the first examples of asymmetric allylic *** reactions proceed via a dynamic kinetic process that allowed for the use of racemic allylic trichloroacetimidates as *** functional theory calculations showed that the formation of the C–OCF_(3)bond occurs via outer-sphere nucleophilic ***,the presence of the allylic group in the products enabled them to be converted into a diverse array of optically active trifluoromethylated molecules that are otherwise difficult to access.

关键词： asymmetric trifluoromethoxylation trifluoromethyl arylsulfonates rhodium trichloroacetimidates chiral diene ligand

Synthesis, crystal structure, photodegradation kinetics and photocatalytic activity of novel photocatalyst ZnBiYO_4

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2015年第3期27卷 51-61页

作者： Yanbing Cui Jingfei luan State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University

ZnBiYO4 was synthesized by a solid-state reaction method for the first time. The structural and photocatalytic properties of ZnBiYO4 were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy and UV-Vis diffuse reflectance. ZnBiYO4 crystallized with a tetragonal spinel structure with space group I41/A. The lattice parameters for ZnBiYO4 were a = b = 11.176479 A and c = 10.014323 A. The band gap of ZnBiYO4 was estimated to be 1.58 eV. The photocatalytic activity of ZnBiYO4 was assessed by photodegradation of methyl orange under visible light irradiation. The results showed that ZnBiY04 had higher catalytic activity compared with N-doped TiO2 under the same experimental conditions using visible light irradiation. The photocatalytic degradation of methyl orange with ZnBiYO4 or N-doped TiO2 as catalyst followed first-order reaction kinetics, and the first-order rate constant was 0.01575 and 0.00416 rain-1 for ZnBiYO4 and N-doped TiO2, respectively. After visible hght irradiation for 220 min with ZnBiYO4 as catalyst, complete removal and mineralization of methyl orange were observed. The reduction of total organic carbon, formation of inorganic products, SO24- and NO3^-, and evolution of CO2 revealed the continuous mineralization of methyl orange during the photocatalytic process. The intermediate products were identified using liquid chromatog- raphy-mass spectrometry. The ZnBiYO4/（visible light） photocatalysis system was found to be suitable for textile industry wastewater treatment and could be used to solve other environmental chemical pollution problems.

关键词： ZnBiYO4 and N-doped TiO2Methyl orangeVisible light irradiationPhotodegradation pathwayStructural properties

EnKF Assimilation of Satellite-retrieved Cloud Water Path to Improve Tropical Cyclone Rainfall Forecast

在线全文

学校读者我要写书评

暂无评论

Journal of Tropical Meteorology 2021年第3期27卷 201-217页

作者： GAO Xiao-yu LIN Yan-luan yuE Jian Ministry of Education Key Laboratory for Earth System Modeling Department of Earth System ScienceTsinghua UniversityBeijing 100084 China Center of Numerical Weather Predication China Meteorological AdministrationBeijing 100081 China

Tropical cyclone(TC) rainfall forecast has remained a challenge. To create initial conditions with high quality for simulation, the present study implemented a data assimilation scheme based on the EnKF method to ingest the satellite-retrieved cloud water path(C_(w)) and tested it in WRF. The scheme uses the vertical integration of forecasted cloud water content to transform control variables to the observation space, and creates the correlations between C_(w) and control variables in the flow-dependent background error covariance based on all the ensemble members, so that the observed cloud information can affect the background temperature and humidity. For two typhoons in 2018(Yagi and Rumiba), assimilating C_(w) significantly increases the simulated rainfalls and TC intensities. In terms of the average equitable threat score of daily moderate to heavy rainfall(5-120 mm), the improvements are over 130%, and the dry biases are cut by about 30%. Such improvements are traced down to the fact that C_(w) assimilation increases the moisture content, especially that further away from the TC center, which provides more precipitable water for the rainfall,strengthens the TC and broadens the TC size via latent heat release and internal wind field adjustment.

关键词： tropical cyclone data assimilation EnKF cloud water path

Field-based evidence for the enrichment of intrinsic antibiotic resistome stimulated by plant-derived fertilizer in agricultural soil

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第1期135卷 728-740页

作者： Shihai Liu Ziming Han Dong Zhu Xiao luan Liujie Deng Liping Dong Min Yang yu Zhang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Environmental Protection Engineering Center for Harmless Treatment and Resource Utilization of Antibiotic Residues Khorgos 835007China University of Chinese Academy of Sciences Beijing 100049China

Animal manures have been demonstrated to enhance antibiotic resistance in agricultural ***,little is known about the effects of plant-derived fertilizer on soil antibiotic ***,metagenomic sequencing was used to investigate the effects of a plantderived fertilizer processed from sugarcane and beet on soil antibiotic resistance genes(ARGs)in a soybean field along crop growth *** profiles in the soils amended by plant-derived fertilizer were compared with those in the soils amended by chicken *** abundance and diversity of total ARGs in the soils amended by plant-derived fertilizer were significantly(Pting nutrients,which was different from the failed establishment of manure-borne bacteria in the manured *** study provided field-based evidence that plant-derived fertilizer stimulated the intrinsic antibiotic resistome,and proposed attention to the un-perceived risk since some clinically relevant ARGs originate and evolve fr

关键词： Organic fertilizer Intrinsic antibiotic resistance Indigenous bacteria Metagenomic sequencing