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Chinese Science Bulletin 2005年第8期50卷 745-751页

作者： MENGJinhong ZHANGHui DavidG.evans DUANXue MinistryofEducationKeyLaboratoryofScienceandTechnologyofControllableChemicalReactions BeijingUniversityofChemicalTechnologyBeijing100029China

Two different interlayer structured glyphosate (GLY) intercalated MgAl layered double hydroxides, as novel pesticide slow/controlled release materials, have been synthesized by co-precipitation method under various reac- tion pH values. The slow/controlled release properties have been tested in Na2CO3 aqueous solution. The release mecha- nism has been interpreted on the basis of the ion-exchange between the guest GLY anions in the lamellar host and 23CO ? in the release media, and the diffusion process of GLY anions in the interstice and interlayer of GLY intercalates, i.e diffusion through the particles, is the rate-limiting step of GLY release process. The GLY intercalate assembled at lower pH, possessing higher interlayer gallery height and vertical monolayered arrangement of guest anions in the interlayer with larger packing density, exhibits better slow release property than that assembled at higher pH. The re- sults reveal that the layered double hydroxides have potential application in the pesticide slow/controlled release area.

关键词：草甘膦杀虫剂氢氧化物原料释放控制

Preparation and photochromic properties of NiAl-NO_3-LDHs/LDPE composite

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Chinese Science Bulletin 2007年第7期52卷 877-882页

作者： CHO Kyuhaeng David G.evans State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

Nanoscale NiAl-NO3-LDHs with good crystallinity have been synthesized by a method, Separate Nucleation and Aging Steps (SNAS). An NiAl-NO3-LDHs/LDPE composite was prepared by blending NiAl-NO3-LDHs and LDPE in a heated double-roller mixer. The color of this composite changed from olive green to steel gray under UV irradiation. After heating at 80oC for 2 h, the color returned to olive green. The effect of varying the amount of added NiAl-NO3-LDHs and UV exposure time on the photochromic properties of the composite has been investigated. The results showed that the photochromic phenomenon becomes more apparent with increasing amount of NiAl-NO3-LDHs. When the amount reaches 5%, the composite exhibits good photochromic properties and reproducibility. The color change rate of the composite reaches a maximum when the irradiation time exceeds 20 min. The addition of LDPE improves the photochromic cyclability of NiAl-NO3-LDHs significantly. The addition of nanoscale NiAl-NO3-LDHs also improves the mechanical properties of LDPE to some extent.

关键词： NiAl-NO3-LDHs 低密度聚乙烯纳米级复合物合成对光反应变色结晶度

Studies on the Surface Properties of MCM-41

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Chemical Research in Chinese Universities 2002年第3期18卷 242-245页

作者： HE Jing DUAN Xue evans DG LI Cheng yue The Key Laboratory of Science and Technology of Controllable Chemical Reactions Ministry of EducationBeijing University of Chemical TechnologyBeijing 100029P.R.China

MCM 41 materials with a well ordered long range structure, a large pore size and a high surface area have been synthesized. Their surface properties including the number and the nature of the surface hydroxyl groups and surface hydrophobicity/hydrophilicity have been investigated by means of 29 Si MAS NMR and FT IR spectra and TPD of probe molecules. The results clearly show that the surface of MCM 41 has an abundance of acidic silanol groups, and that the hydrophobicity/hydrophilicity can be modified by the introduction of Al and transition metals Ti, Cr, Ni and Fe into it.

关键词： Hydroxyl group Hydrophobicity/Hydrophilicity MCM 41

Temporal and spatial variations of air pollution across China from 2015 to 2018

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Journal of Environmental Sciences 2022年第2期34卷 161-169页

作者： Xiaoteng Zhou Vladimir Strezov Yijiao Jiang Tao Kan Tim evans ARC Research Hub for Computational Particle Technology Macquarie UniversitySydneyNew South Wales 2109Australia Department of Earth and Environmental Sciences Faculty of Science and EngineeringMacquarie UniversitySydneyNew South Wales 2109Australia School of Engineering Faculty of Science and EngineeringMacquarie UniversitySydneyNew South Wales 2109Australia

This study investigated concentrations of PM_(2.5),PM_(10),SO_(2),NO_(2),CO and O_(3),and air quality index(AQI)values across 368 cities in China's Mainland during 2015–*** study further examined relationships of air pollution status with local industrial capacities and vehicle *** correlations were found between industrial capacities(coal,pig iron,crude steel and rolled steel)and air pollution *** statistical and significant reductions of PM_(2.5),PM_(10),SO_(2),NO_(2),CO and AQI values were observed in response to various laws and regulations in industrial sectors,both particle and gaseous pollutants still had annual average concentrations above recommended *** order to further reduce air pollution,more efforts can be done to control traffic emissions caused by minicars and heavy trucks,which was revealed after investigating 16 vehicle *** was also consistent with the apparent air quality improvement during the COVID-19 lockdown period in China in 2020,despite industrial operations being still active at full capacities.

关键词： PM_(2.5) PM_(10) SO_(2) NO_(2) Industrial products Vehicle numbers

Layer-by-layer assembly of long-afterglow self-supporting thin films with dual-stimuli-responsive phosphorescence and antiforgery applications

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Nano Research 2017年第10期10卷 3606-3617页

作者： Rui Gao Dongpeng Yan David G. evans Xue Duan State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China Beijing Key Laboratory of Energy Conversion and Storage Materials College of Chemistry Beijing Normal University Beijing 100875 China

The assembly of thin films （TFs） having long-lasting luminescence can be expected to play an important role in the development of new-generation smart sensors, anti-counterfeiting materials, and information-encryption systems. However, such films are limited compared with their powder and solution counterparts. In this study, by exploiting the self-organization of phosphors in the two-dimensional （2D） galleries between clay nanosheets, we developed a method for the ordered assembly of long-afterglow TFs by utilizing a hydrogen-bonding layer-by-layer （LBL） process. Compared with the pristine powder, the TFs exhibit high polarization and up-conversion room-temperature phosphorescence （RTP）, as well as enhanced quantum yields and luminescence lifetimes, allowing them to be used as room-temperature phosphorescent sensors for humidity and oxygen. Moreover, modified clay-based hybrids with multicolor RTP can serve as anti-counterfeiting marks and triple-mode 2D barcode displays. We anticipate that the LBL assembly process can be extended to the fabrication of other inorganic--organic room-temperature phosphorescent hybrids with smart luminescent sensor and antiforgery applications.

关键词： layer-by-layer self-supporting thin film two-dimensional (2D) ultrathin nanosheets sensor phosphorescence

Institutional Repositories and Research Data Management:challenges and opportunities

维普期刊数据库评论

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维普期刊数据库

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中国科技期刊研究 2015年第1期26卷 8-10页

作者： James evans Bev Acreman Open Repository BioMed Central

Mandated storage,curation and management of research data is likely to significantly challenge and change established institutional repository processes in coming *** the major repository conferences,management of research data and metadata has been the hot topic of recent *** biggest institutions with large research communities and

关键词：科技期刊元数据数据管理发行工作

On-going nitrification in chloraminated drinking water distribution system(DWDS) is conditioned by hydraulics and disinfection strategies

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Journal of Environmental Sciences 2020年第10期32卷 151-162页

作者： Yi Shi Akintunde Babatunde Bettina Bockelmann-evans Qijie Li Liang Zhang National Engineering Laboratory for Cereal Fermentation Technology Jiangnan UniversityWuxi 214122China Discipline of Ciuil Engineering Cardiff University School of EngineeringThe ParadeCardiffCF243AAUK School of Civil Engineering University of LeedsLeedsLS29JTUK

Within the drinking water distribution system(DWDS)using chloramine as disinfectant,nitrification caused by nitrifying bacteria is increasingly becoming a concern as it poses a great challenge for maintaining water *** investigate efficient control strategies,operational conditions including hydraulic regimes and disinfectant scenarios were controlled within a flow cell experimental *** test phases were conducted to investigate the effects on the extent of nitrification of three flow rates(Q=2,6,and 10 L/min)and four disinfection scenarios(total Cl2=1 mg/L,Cl2/NH3-N=3:1;total Cl2=1 mg/L,Cl2/NH3-N=5:1;total Cl2=5 mg/L,Cl2/NH3-N=3:1;and total Cl2=5 mg/L,Cl2/NH3-N=5:1).Physico-chemical parameters and nitrification indicators were monitored during the *** characteristics of biofilm extracellular polymetric substance(EPS)were evaluated after the *** main results from the study indicate that nitrification is affected by hydraulic conditions and the process tends to be severe when the fluid flow transforms from laminar to turbulent(2300

关键词： Nitrification Drinking water distribution system(DWDS) Biofilm Hydraulics Disinfection

Influence of nano-MgO particle size on bactericidal action against Bacillus subtilis var. niger

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Chinese Science Bulletin 2005年第6期50卷 514-519页

作者： HUANGLei LIDianqing LINYanjun DavidG.evans DUANXue KeyLaboratoryofScienceandTechnologyofControllableChemicalReactions MinistryofEducationBeijingUniversityofChemicalTechnologyBeijing100029China

Nano-MgO with various particle sizes, synthe- sized by different methods using Mg(NO3)2·6H2O, Na2CO3, Na2SO4, urea and ammonia solution as reactants, was used to carry out bactericidal experiments on Bacillus subtilis var. niger. The results were compared with the effect of TiO2, a common kind of photocatalytic material. The materials were characterized by X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), low temperature N2 adsorp- tion-desorption measurements and FT-IR, and the results showed that the bactericidal ability of MgO increases with decreasing particle size. Nano-MgO and an interior wall-paint containing the material have better bactericidal effects than nono-TiO2 in both presence and absence of light. The bactericidal mechanism is discussed. The surface of MgO can generate high concentrations of O?2 which is highly active and can react with the peptide linkages in the coating walls of the spores. The spores are destroyed by the resulting damage to their structure.

关键词：氧化镁合成方法 “Bacillus subtilis var.niger” 杀菌活性细菌氧离子晶体

Ti-modified Mesoporous Molecular Sieves Containing both Selective Oxidation and Photocatalysis Centers

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Chemical Research in Chinese Universities 2004年第4期20卷 386-391页

作者： GUOZong-ying HEJing DavidG.evans DUANXue ZHUYue-xiang XIAOTian-cun TheKeyLaboratoryofScienceandTechnologyofControllableChemicalReactionsofMinistryofEducation BeijingUniversityofChemicalTechnologyBeijing100029P.R.China StateKeyLaboratoryforStructuralChemistryofUnstableandStableSpecies CollegeofChemistryandMolecularEngineeringPekingUniversityBeijing100871P.R.China InorganicChemistryLaboratory OxfordUniversityOX13QRUK

Mesoporous molecular sieves possessing high mesopore volumes and large specific surface areas were prepared and characterized by means of XRD, low temperature N_2 adsorption-desorption measurements, FT IR, Raman, UV-visible diffuse reflectance and XPS spectroscopy. The materials contain both framework and extra-framework Ti centers which exhibit selective oxidation catalytic activity and photocatalytic activity respectively. The catalysis of selective oxidation was studied with the hydroxylation of benzene with hydrogen peroxide and photochemical activity was studied by the yields of ·OH and H_2O_2, respectively.

关键词： Ti-modified mesoporous materials Framework sites Non-framework sites Selective oxidation Photocatalysis

Predicting pollutant removal in constructed wetlands using artificial neural networks(ANNs)

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Water Science and Engineering 2020年第1期13卷 14-23页

作者： Christopher Kiiza Shun-qi Pan Bettina Bockelmann-evans Akintunde Babatunde Hydro-environmental Research Centre School of EngineeringCardiff UniversityThe ParadeCardiff CF243AAUK School of Civil Engineering University of LeedsLeeds LS29JTUK

Growth in urban population,urbanisation,and economic development has increased the demand for water,especially in water-scarce ***,sustainable approaches to water management are needed to cope with the effects of the urbanisation on the water *** study aimed to design novel configurations of tidal-flow vertical subsurface flow constructed wetlands(VFCWs)for treating urban stormwater.A series of laboratory experiments were conducted with semi-synthetic influent stormwater to examine the effects of the design and operation variables on the performance of the VFCWs and to identify optimal design and operational strategies,as well as maintenance *** results show that the VFCWs can significantly reduce pollutants in urban stormwater,and that pollutant removal was related to specific VFCW *** based on the artificial neural network(ANN)method were built using inputs derived from data exploratory techniques,such as analysis of variance(ANOVA)and principal component analysis(PCA).It was found that PCA reduced the dimensionality of input variables obtained from different experimental design *** results show a satisfactory generalisation for predicting nitrogen and phosphorus removal with fewer variable inputs,indicating that monitoring costs and time can be reduced.

关键词： Constructed wetlands Urban stormwater Pollutant removal Artificial neural networks(ANNs) Principal component analysis(PCA)