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Synthesis of layered LiMnO_2 by in situ oxidation-intercalation and a study of the reaction mechanism and electrochemical performance

American Journal of Analytical Chemistry（美国分析化学） 2024年第4期 139页

作者： Taheim evans English Meghann Trombetta Alyssa Beres Yusuf Yildiz

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Chinese Science Bulletin 2005年第3期50卷 213-216页

作者： D.G.evans Key Laboratory of Science and Technology of Controllable Chemical Reactions Ministry of EducationBeijing University of Chemical Tech- nologyBeijing 100029China

Using Mn(OH)2 as precursor, LiOH as lithiat- ing agent and (NH4)2S2O8 as oxidant, layered o-LiMnO2 was obtained by a novel method——in situ oxidation-intercalation under mild conditions (80℃). The product was characterized by XRD, ICP, TEM and Li-NMR. The results reveal that 7 orthorhombic LiMnO2 with high purity and good crystallin- ity can be obtained by this method. During electrochemical tests, a LiMnO2/Li cell shows an initial reversible capacity of 208 mAh·g?1 and a reversible capacity of 180 mAh·g?1 after 30 cycles at room temperature.

关键词： LiMnO2 氧化反应电化学特性锂离子电池分析方法

Does the autonomic nervous system contribute to the initiation and progression of prostate cancer？

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Asian Journal of Andrology 2013年第6期15卷 715-716页

作者： Sabatino Ventura Bronwyn A evans Drug Discovery Biology Monash Institute of PharmaceuticalSciences Monash University Parkville Vic. 3052 Australia

In the July 12 issue of Science maga-zine, researchers from the AlbertEinstein College of Medicine, the Mount Sinai School of Medicine, the Durham VA Medical Centre and Duke University published an elegant study demonstrating that the sym-pathetic nervous system, acting through β2 and β3-adrenoceptors in the prostate, plays an important role in the initiation of prostate can-cer, while the parasympathetic nervous system plays a role in the dissemination of tumour metastases via M1 muscarirdc receptors. These findings are significant because they indicate that receptors associated with the autonomic nervous system may be viable tar-gets for prostate cancer therapy.

关键词： GROWTH SWITCH

Misalignment Between Skills Discovered, Disseminated, and Deployed in the Knowledge Economy

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Journal of Social Computing 2022年第3期3卷 191-205页

作者： Bhargav Srinivasa Desikan James evans the Department of Computer and Communication Sciences École Polytechnique Fédérale de Lausanne(EPFL)Lausanne 1015Switzerland the Knowledge Lab the Department of SociologyUniversity of ChicagoChicagoIL 60615USAand also with the Santa Fe InstituteSanta FeNM 87501USA

The knowledge economy is a complex and dynamical system,where knowledge and skills are discovered through research,diffused via education,and deployed by *** aligning the supply of new knowledge with the demand for practical skills through education is critical for developing national innovation systems that maximize human *** this paper,we evaluate the complex alignment of skills across the knowledge economy by creating an integrated semantic model that neurally encodes invented,instructed,and instituted skills across three major datasets:research abstracts from the Web of Science,teaching syllabi from the Open Syllabus Project,and job advertisements from Burning *** the high dimensional knowledge and skills space inscribed by these data,we draw critical insight about systemic misalignment between the diversity of skills supplied and demanded in the knowledge *** with insights from economic geography,demand for skills from industry exhibits high entropy(diversity)at local,regional,and national levels,demonstrating dense complementarities between them at all levels of the *** with the economics and sociology of innovation,we find low entropy in the invention of new knowledge and skills through research,as specialist researchers cluster within *** provide new evidence,however,for the low entropy of skills taught at local,regional,and national levels,illustrating a massive mismatch between diversity in skills supplied versus *** misalignment is sustained by the spatial and institutional mismatch in the organization of education by researchers at the site of skill invention over *** findings suggestively trace the societal costs of tethering education to researchers with narrow knowledge rather than students with broad skill needs.

关键词： computational content analysis knowledge economy sociology of knowledge natural language processing data science and society

Case study of a driven pile foundation in diatomaceous soil.I:Site characterization and engineering properties

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 431-445页

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

Diatomaceous soils are comprised of the silica frustules of diatom microalgae that are present in marine and lacustrine environments throughout the *** to their unique origin,diatomaceous soils are typically characterized by high intraparticle porosity,complex particle shapes,and uniform mineralogy,causing them to exhibit atypical physical and engineering behaviors.A substantial deposit of diatomaceous silt was observed during site exploration for construction of the Buck Creek Bridge on OR140 near Klamath Falls,OR,USA.A comprehensive laboratory and in situ testing program indicated that the diatomaceous soil possessed“non-textbook”engineering ***,tested samples had high liquid limits(≈100%-140%)with natural water contents at or near the liquid ***,the soil is expected to be normally consolidated,yet high apparent overconsolidation ratios(OCR)(≈15-40)were observed both in oedometric consolidation tests and through cone penetration test(CPT)*** penetration test(SPT)results show a corrected standard penetration resistance consistent with a medium-dense sand(i.e.(N1)_(60)≈25).CPT results include corrected tip resistances(qt)of approximately 7-10 MPa and excess pore pressures(u_(2))of up to 4 *** CPT dissipation tests,pore water pressures(PWPs)returned to hydrostatic pressure in less than 1 *** this work,we synthesize these seemingly disparate material properties in an attempt to infer appropriate engineering properties for the diatomaceous deposit at the Buck Creek Bridge and attempt to provide insight into the underlying reasons for the observed behavior.

关键词： Diatomaceous soil Problematic soil Site characterization Laboratory testing

Ultrasound-assisted microfeeding of fine powders

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Particuology 2008年第1期6卷 2-8页

作者： Xuesong Lu Shoufeng Yang Julian R.G. evans Department of Materials Queen Mary University of London Mile End Road London E1 4NS UK

Ultrasonic microfeeding of powders is a new and promising method for use in solid freeforming and pharmaceutical dosing. In this work, computer-controlled microfeeding systems using ultrasonic vibration of a capillary were built. A wide range of controlled, stable rates of flow and switching control were achieved in the acoustic vibration system and uniform powder doses were obtained in the ultrasonic system. Experimental results show that nozzle diameter, transmission fluid depth, waveform, voltage amplitude, frequency and oscillation duration all influence the dose mass. Among these factors, nozzle diameter, voltage amplitude and oscillation duration can be best used to control the dose mass. An artificial neural network （ANN） technique was applied to predict the dose mass. Based on these research results, four types of microfeeding were proposed.

关键词： Microfeeding Ultrasound Fine powders

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

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