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Case study of a driven pile foundation in diatomaceous ***:Pile installation,dynamic analysis,and pore pressure generation

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 446-456页

作者： Ehsan Yazdani Jiayao Wang T.Matthew evans School of Civil and Construction Engineering Oregon State UniversityCorvallisOR97331USA

This paper presents the results from a case study highlighting the difficulties of pile driving in diatomaceous *** the companion(first)paper to this article,results of an extensive laboratory and in situ testing program were presented while the results from pile driving and further analysis of field observations were presented *** high pile rebound(HPR)was observed during driving of a closed-end pipe pile,with refusal occurring at a depth of less than 5 *** open-ended piles were thus *** and case pile wave analysis program(CAPWAP)data were collected during driving of both closed-and open-end *** data indicated that negative pore water pressures(PWPs)were generated while the closed-ended pile exhibited high *** from in situ tests indicated change in material stiffness and strong dilative tendencies near the depth of refusal.A hypothesis for observed behavior was proposed that considers the soil beneath the pile as a medium with an effectively infinite bulk modulus.

关键词： Diatomaceous soil Problematic soil Site characterization Laboratory testing

Structure, flame retarding and smoke suppressing properties of Zn-Mg-Al-CO3 layered double hydroxides

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Chinese Science Bulletin 2005年第11期50卷 1101-1104页

作者： evans D. G. Key Laboratory for Science and Technology of Controllable Chemical Reactions Ministry of Education Beijing University of Chemical Tech- nology Beijing 100029 China

Zn-Mg-Al-CO3 layered double hydroxides (LDHs) have been synthesized by a new method involving separate nucleation and aging steps. The Zn-Mg-Al-CO3 LDHs were characterized by XRD, FT-IR, ICP and TG-DTA. The limiting oxygen index and smoke density of composites of the LDHs with EVA-28 were determined. Incorporation of Zn2+ in the layers of the LDHs was found promoting mate- rial charring and smoke suppression. The mechanism of flame retardation and smoke suppression is discussed. The results show that Zn-Mg-Al-CO3 LDHs have better flame retarding and smoke suppressing effects than Mg-Al-CO3 LDHs.

关键词：分层双氢氧化物烟尘控制成核现象火焰延迟

Epidemiology of burns and scalds in children presenting to the emergency department of a regional burns unit: a 7-year retrospective study

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Burns & Trauma 2016年第3期4卷 245-250页

作者： Ceri Elisabeth Battle Vanessa evans Karen James Katherine Guy Janet Whitley Phillip Adrian evans Department of Emergency Medicine NISCHR Haemostasis Biomedical Research UnitMorriston HospitalSwanseaUK Department of Physiotherapy Morriston HospitalSwanseaUK Department of Emergency Medicine NISCHR Haemostasis Biomedical Research UnitMorriston HospitalSwanseaUK Department of Physiotherapy Morriston HospitalSwanseaUK Department of Emergency Medicine Morriston HospitalSwanseaWales SA66NLUK

Background:Variation in the incidence and mechanism of thermal injury has been reported in different age groups in *** aim of this study was to report the incidence,mechanisms,and environmental factors of all burns presentations to the emergency department(ED)of a regional burns centre over a 7-year ***:A retrospective,chart review study of all burns presentations to the ED of a regional burns centre in South Wales was *** children recorded as having sustained a burn or scald,aged less than 16 years were included in the ***’demographics were analysed using descriptive statistics,and comparisons were made between patients aged less than 5 and patients aged 5-16 using chi-square test and Mann-Whitney U ***:A total of 1387 cases were included in the final *** were the most common thermal injury with 569(41.0%)reported,followed by contact burns in 563(40.6%)*** patients requiring hospitalisation were significantly younger(2 vs 3 years;p<0.001)and had a higher rate of non-accidental injury(10 vs 4;p<0.001).The most commonly injured site in both age groups was a hand or ***:Scalds and contact burns were the most commonly reported thermal injury in children aged less than *** mechanisms were hot beverages,hobs and hair straighteners,highlighting further burn prevention strategies are needed and good-quality prospective studies that investigate the effectiveness of such strategies.

关键词： Burns epidemiology Paediatrics Emergency department

Novel layered pesticide slow/controlled release materials——supramolecular structure and slow release property of glyphosate intercalated layered double hydroxides

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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

Synthesis and characterization of nanoscale magnetic drug-inorganic composites

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Chinese Science Bulletin 2005年第8期50卷 752-757页

作者： SUNHui ZHANGHui DavidG.evans DUANXue MinistryofEducationKeyLaboratoryofScienceandTechnologyofControllableChemicalReactions BeijingUniversityofChemicalTechnologyBeijing100029China

The synthesis by direct coprecipitation and characterization of captopril (Cpl) and 5-aminosalicylic acid (5-ASA) intercalated ZnAl layered double hydroxides coated on MgFe2O4 magnetic core particles are reported. Powder XRD analysis shows the well-defined crystallite structure of the composites. TEM and XPS results reveal that a core-shell structure involving a drug-LDHs layer coated on MgFe2O4 particles is formed through Zn-O-Mg and/or Al-O-Mg link- ages. VSM measurements demonstrate that the novel mag- netic drug-inorganic composites possess considerable mag- netization.

关键词：磁性指标药物锌铝分层氢氧化物沉淀物

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

Sphincter of Oddi dysfunction:Psychosocial distress correlates with manometric dyskinesia but not stenosis

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World Journal of Gastroenterology 2009年第48期15卷 6080-6085页

作者： Ethelle Bennett Peter evans John Dowsett John Kellow Department of Gastroenterology and Medicine Royal NorthShore HospitalUniversity of Sydney

AIM:To compare postcholecystectomy patients with Sphincter of Oddi(SO)dyskinesia and those with normal SO motility to determine the psychosocial distress,gender and objective clinical correlates of dyskinesia,and contrast these findings with comparisons between SO stenosis and normal SO ***:Within a cohort of seventy-two consecutive postcholecystectomy patients with suspected SO dysfunction,manometric assessment identified subgroups with SO dyskinesia(n=33),SO stenosis(n=18)and normal SO motility(n=21).Each patient was categorized in terms of Milwaukee Type,sociodemographic status and the severity of stress-coping ***:Logistic regression revealed that in combination certain psychological,sociodemographic and clinical variables significantly differentiated SO dyskinesia,but not SO stenosis,from normal SO *** of psychosocial stress and of coping with this stress(*** suppressed more frequently and the use of significantly more psychological coping strategies)were highest among patients with SO dyskinesia,especially *** levels of neuroticism(the tendency to stressproneness)further increased the likelihood of SO ***:A motility disturbance related to psychosocial distress may help to explain the finding of SO dyskinesia in some postcholecystectomy patients.

关键词： Gender Functional gastrointestinal disorders Psychosocial distress Sphincter of Oddi dyskinesia

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