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Synthesis and Purple-Blue Emission of Antimony Trioxide Single-Crystalline Nanobelts with Elliptical Cross Section

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Nano Research 2009年第2期2卷 151-160页

作者： Zhengtao Deng Dong Chen Fangqiong Tang Jun Ren anthony J.Muscat Laboratory of Controllable Preparation and Application of Nanomaterials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100080China Department of Chemical and Environmental Engineering The University of ArizonaTucsonArizona 85721USA College of optical Science The University of ArizonaTucsonArizona 85721USA

Single-crystalline orthorhombic antimony trioxide(Sb_(2)o_(3))nanobelts with unique elliptical cross sections and purple-blue photoluminescence have been *** uniform Sb2o3 nanobelts are 400600 nm in width,2040 nm in thickness at the center and gradually become thinner to form sharp edges sub-5 nm in size,tens of micrometers in length,and with[001]as the preferential growth ***-assembly of tens of nanobelts into three-dimensional(3-D)flower-like nanostructures has been *** was performed by X-ray diffraction,energy-dispersive X-ray spectroscopy,X-ray photoelectron spectroscopy,scanning electron microscopy,high-resolution transmission electron microscopy,selected area electron diffraction,Raman spectroscopy,Fourier transform infrared spectroscopy,and photoluminescence *** Sb_(2)o_(3) nanobelts display intense purple-blue photoluminescence centred at 425 nm(~2.92 eV).The successful synthesis of nanobelts with elliptical cross sections may cast new light on the investigation of the property differences between nanobelts with rectangular cross sections and those with other cross section *** Sb2o3 nanobelts can be used as effective purple-blue light emitters and may also be valuable for future nanodevice design.

关键词： Antimony trioxide nanobelts elliptical cross section purple-blue photoluminescence

Crystallographic Analysis of Isothermally Transformed Bainite in 0.2C-2.0Mn-1.5Si-0.6Cr Steel Using EBSD

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Journal of Materials Science & Technology 2013年第4期29卷 359-366页

作者： Pasi P.Suikkanen Cyril Cayron anthony J.DeArdo L.Pentti Karjalainen Ruukki Metals oy Rautaruukintie 155P.O.Box 93FI-92101 RaaheFinland Department of Mechanical Engineering University of OuluP.O.Box 420090014 University of OuluFinland Ruukki Metals oy Rautaruukintie 155P.O.Box 93FI-92101 RaaheFinland. CEA LITEN17 rues des Martys38054 GrenobleFrance Department of Mechanical Engineering and Materials Science University of Pittsburgh848 Benedum HallPittsburghPA 15261-2285USA

The crystallography of bainite, transformed isothermally at 450 ℃ in 0.2C-2.0Mn-1.5Si-0.6Cr steel, was investigated by electron backscatter diffraction （EBSD） analysis. The orientation relationship （oR） was found to be closer to Nishiyama-Wassermann （N-W） than Kurdjumov-Sachs orientation relationship. Bainite microstructure consisted of parallel laths forming a morphological packet structure. Typically, there were three different lath orientations in a morphological packet. These orientations were dictated by a three specific N-W oR variants sharing the same {111} austenite plane. A packet of bainite laths with common {111} austenite plane was termed as crystallographic packet. Generally, the crystallographic packet size corresponded to the morphological packet size. Locally, crystallographic packets with only two dominant orientations were observed. This indicates strong local variant selection during isothermal bainite transformation. The relative orientation between the variants in crystallographic packets was found to be near 60°/〈110〉. This appears to explain the strong peak observed in the grain boundary misorientation distribution near 60°. Bainite also contained pronounced fraction of boundaries with their misorientation in the range of 2.5°-8° with quite widely dispersed rotation angles. Spatially these boundaries were found to locate inside the bainite laths, forming lath-like sub-grains.

关键词： Bainite Austenite Nishiyama-Wassermann orientation relationship Electron backscatter diffraction oEBSD) Crystallography Packet

Incidence rate of prostate cancer in men treated for erectile dysfunction with phosphodiesterase type 5 inhibitors： retrospective analysis

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Asian Journal of Andrology 2013年第2期15卷 246-248,I0008页

作者： anthony H Chavez K Scott Coffield M Hasan Rajab Chanhee Joe Departments of Urology Scott & White Healthcare Temple Texas 76508 USA Departments of Biostatistics Scott & White Healthcare Temple Texas 76508 USA Deparment of Biostatistics College of Medicine Alfaisal University Riyadh 11533 Saudi Arabia

The purpose of this study was to determine the incidence rate of prostate cancer among men with erectile dysfunction （ED） treated with phosphodiesterase type 5 inhibitors （PDE-5i） over a 7-year period vs. men with ED of the same age and with similar risk factors who were not treated with PDE-5i. In a retrospective review of electronic medical records and billing databases between the years 2000 and 2006, men with ED between the ages of 50 and 69 years and no history of prostate cancer prior to 2000 were identified. These individuals were divided into two groups： 2362 men who had treatment with PDE-5i, and 2612 men who did not have treatment. Demographic data in each group were compared. During the study period, 97 （4.1%） men with ED treated with PDE-5i were diagnosed with prostate cancer compared with 258 （9.9%） men with ED in the non-treated group （P〈00001）. A higher percentage of African Americans were treated with PDE-5i vs. those who were not （10.5% vs. 7.1%; P〈o.o001）. The PDE-5i group had lower documented diagnosis of elevated prostate-specific antigen （10.0% vs. 13.1%; P=-0.0008） and higher percentage of benign prostatic hyperplasia （38.4% vs. 35.1%; P=0.0149）. Men with ED treated with PDE-5i tended to have less chance （adjusted odds ratio： 0.4; 95% confidence intervals： 0.3-0.5; P〈0.0001） of having prostate cancer. our data suggest that men with ED treated with PDE-5i tended to have less of a chance of beine diaenosed with orostate cancer. Further research is warranted.

关键词： erectile dysfunction (ED) phosphodiesterase 5 inhibitors (PDE-5i) prostate cancer prostatic neoplasms

Small gold clusters catalyzing oxidant-free dehydrogenation of glycerol initiated by methene hydrogen atom transfer

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Chinese Chemical Letters 2019年第5期30卷 1000-1004页

作者： anthony M.S.Pembere Chaonan Cui Haiming Wu Zhixun Luo State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Developing oxygen-free methodology for the conversion of alcohols to carbonyls is essentially important because it suppresses the over-oxidation of alcohols to carboxylic acids and enables the production of energetic *** we report a finding of feasible oxidant-free dehydrogenation of glycerol over chemically-pure Au clusters synthesized by a green chemistry method named as laser ablation in liquid(LAL).As results,glycerol is dehydrogenated to form glyceraldehyde which undergoes subsequent dehydrogenation to hydroxymethyl *** this,reaction dynamics calculations find interesting dehydrogenation reaction pathways with a low-energy barrier of transition state initiated by hydrogen atom transfer from methene,which differs from the general reaction mechanism based on ***,it is interesting that the presence of additionalààoH group molecules especially H2o can effectively lower the energy barrier in the activation of the oààH and CààH bonds in *** principle is also applicable to the oxidant-free dehydrogenation of methanol and ethanol,helping to fully understand the catalytic mechanism of alcohols conversion chemistry.

关键词： Density functional theory Alcohols Bond activation Reaction path Energy barrier

Poly(lactic acid)-starch/Expandable Graphite (PLA-starch/EG) Flame Retardant Composites

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Journal of Renewable Materials 2018年第1期6卷 26-37页

作者： Mfiso Emmanuel Mngomezulu Adriaan Stephanus Luyt Steve anthony Chapple Maya Jacob John Department of Chemistry University of the Free State(Qwaqwa Campus)Private Bag X13Phuthaditjhaba 9866South Africa Center for Advanced Materials Qatar UniversityPO Box 2713DohaQatar CSIR Materials Science and Manufacturing Polymers and Composites Competence AreaPO Box 1124Port Elizabeth 6000South Africa Department of Chemistry Faculty of ScienceNelson Mandela Metropolitan UniversityPO Box 1600Port Elizabeth 6000South Africa

This work reports on the effect of commercial expandable graphite(EG)on the flammability and thermal decomposition properties of PLA-starch *** PLA-starch/EG composites were prepared by melt-mixing and their thermal stability,volatile pyrolysis products and flammability characteristics were *** char residues of the composites,after combustion in a cone calorimeter,were analyzed with environmental scanning electron microscopy(ESEM).The thermal decomposition stability of the composites improved in the presence of ***,the char content was less than expected as per the combination of the wt%EG added into PLA-starch and the%residue of *** flammability performance of the PLA-starch/EG composites improved,especially at 15 wt%EG content,due to a thick and strong worm-like char *** peak heat release rate(PHRR)improved by 74%,the total smoke production(TSP)by 40%and the specific extinction area(SEA)by 55%.The improvements are attributed to the ability of EG to exfoliate at increased temperatures during which time three effects occurred:(i)cooling due to an endothermic exfoliation process,(ii)dilution due to release of H2o,So2 and Co2 gases,and (iii)formation of a protective intumescent char ***,the Co and Co2 yields were found to be unfavorably high due to the presence of EG.

关键词： Poly(lactic acid)-starch composites expandable graphite thermal stability flammability properties

Fire safety of complex buildings (tall buildings, tunnels, subways, etc)

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Building Simulation 2022年第4期15卷 493-494页

作者： Jie Ji anthony Hamins Simo Hostikka Mehdi Jangi Futoshi Tanaka Long Ding State Key Laboratory of Fire Science University of Science and Technology of ChinoJinZhai Road 96HefeiAnhui 230026China National Institute of Standards and Technology 100 Bureau Dr.GaithersburgMDUSA Department of Civil Engineering School of EngineeringAalto UniversityRakentajanaukio 4A02150 EspooP.O.Box 1210000076 AaltoFinland School of Mechanical Engineering University of BirminghamEdgbastonBirminghamB152TTUK Mechanical Engineering Faculty of EngineeringUniversity of Fukui3-9-1 BunkyoFukui-shiFukui910-8507Japan

Urbanization has accelerated over the last few *** increasing number of complex structures,such as high-rise buildings,city underground tunnels,and subways,are being built to relieve the increasing pressure of traffic congestion and inefficient use of urban *** attention has been paid to the fire safety of these complex structures because of many disastrous fire accidents reported worldwide.

关键词： Urbanization underground complex

A Comprehensive Comparison of the Analytical and Numerical Prediction of the Thermal History and Solidification Microstructure of Inconel 718 Products Made by Laser Powder-Bed Fusion

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Engineering 2017年第5期3卷 685-694页

作者： Patcharapit Promoppatum Shi-Chune Yao P. Chris Pistorius anthony D. Rollett Department o.f Mechanical Engineering Carnegie Mellon University Pittsburgh PA 15213 USA Department of Materials Science and Engnneering Carnegie Mellon University Pittsburgh PA 15213 USA

The finite-element （FE） model and the Rosenthal equation are used to study the thermal and microstructural phenomena in the laser powder-bed fusion of lnconel 718. A primary aim is to comprehend the advantages and disadvantages of the Rosenthal equation （which provides an analytical alternative to FE analysis）, and to investigate the influence of underlying assumptions on estimated results. Various physical characteristics are compared among the FE model, Rosenthal equation, and experiments. The predicted melt pool shapes compared with reported experimental results from the literature show that both the FE model and the analytical （Rosenthal） equation provide a reasonably accurate estimation. At high heat input, under conditions leading to keyholing, the reported melt width is narrower than predicted by the analytical equation. Moreover, a sensitivity analysis based on choices of the absorptivity is performed, which shows that the Rosenthal approach is more sensitive to absorptivity, compared with the FE approach. The primary reason could be the effect of radiative and convective losses, which are assumed to be negligible in the Rosenthal equation. In addition, both methods predict a columnar solidification microstructure, which agrees well with experimental reports, and the primary dendrite arm spacing （PDAS） predicted with the two approaches is comparable with measurements.

关键词： Additive manufacturing Finite-element modeling Rosenthal equation Microstructure Thermal behavior Inconel 718

Large electromechanical strain at high temperatures of novel <001> textured BiFeGao3-BaTio3 based ceramics

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Journal of Materials Science & Technology 2020年第13期47卷 92-99页

作者： Jiangguli Peng Wenbin Liu Jiangtao Zeng Liaoying Zheng Guorong Li anthony Rousseau Alain Gibaud Abdelhadi Kassiba Key Laboratory of Inorganic Functional Material and Device Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 201899China Institut des Molécules et Matériaux du Mans(IMMM) CNRS UMR 6283Facultédes SciencesUniversitédu MaineAvenue O.Messiaen72085 Le MansCedex 09France Center of Materials Science and optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

BiFeGao3-BaTio3(BFG-BT)based ceramics with a large piezoelectric coefficient are potential high performance lead-free piezoelectric *** this work,textured and random BFG-BT ceramics were realized by the solid state reaction method with and without BaTio3(BT)*** ceramics were obtained by a reactive templated grain growth(RTGG)method leading to a high-temperature electromechanical strain of S=0.27%at 40 kV/cm and to an effective piezoelectric coefficient(d33*)up to 685 pm/V at 180℃.The easy movement of oriented domains enhanced the electromechanical strain under an applied electric field in textured sample(Lotgering factor f=66.3%).Structural investigations reveal that the proportion and degree of distortion of BFG-BT rhombohedral phase(R3c)reached its maximum in textured ceramics,resulting in large ferrodistortive displacements under electric *** addition,the dense nanodomains with low domain wall energies,inferred from the high-resolution transmission electron microscope(HR-TEM)observations,contribute to the extra displacement of the textured sample under an applied electric *** textured ceramics,the remnant polarization was stable(about 17μC/cm2)from room temperature to 180℃,contributing to the stable ferroelectric property at high *** the introduction of BT templates,high-density nanodomains were formed and the Burns temperature was enhanced in textured *** electromechanical strain,polarization and dielectric behavior were correlated to the textured or random forms of the BFG-BT based ceramics.

关键词： Textured ceramics Strain hysteresis Reactive templated grain growth Dielectric responses

Addition of castor oil as a booster in colon capsule regimens significantly improves completion rates and polyp detection

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World Journal of Gastrointestinal Pharmacology and Therapeutics 2021年第6期12卷 103-112页

作者： Serhiy Semenov Mohd Syafiq Ismail Fintan o'Hara Sandeep Sihag Barbara Ryan anthony o'Connor Sarah o'Donnell Deirdre McNamara Gastroenterology Department Tallaght University HospitalDublin D 24Ireland Trinity Academic Gastroenterology Group Trinity College DublinDublin D 2Ireland

BACKGRoUND Incomplete excretion rates are problematic for colon capsule endoscopy(CCE).Widely available booster regimens are *** published data on one day preparation CCE protocol using castor oil appeared *** To assess the impact of adding castor oil to a standard split-dose(2-d)preparation in an unselected Western patient *** All patients aged 18 or more referred to our unit for a CCE over a 5-mo period were prospectively *** were retrospectively identified from our CCE *** patients received split bowel preparation with Moviprep■[polyethylene glycol(PEG)-3350,sodium sulphate,sodium chloride,potassium chloride,sodium ascorbate and ascorbic acid for oral solution;Norgine B.V,United States],a PEG-based solution used predominantly in our colonoscopy *** booster regimen included Moviprep■with 750 mL of water(booster 1)on reaching the small bowel.A further dose of Moviprep■with 250 mL of water was given 3 h later and a bisacodyl suppository(Dulcolax■)10 mg after 8 h,if the capsule was not *** addition to our standard booster regimen,cases received an additional 15 mL of castor oil given at the time of booster 1.A nested case control design with 2:1 ratio(control:case)was *** demographics,completion rates,image quality,colonic transit time,diagnostic yield and polyp detection were compared between groups,using a student t or chi-square tests as *** one hundred and eighty-six CCEs[mean age 60 years(18-97),56%females,n=104],including 62 cases have been *** breakdown included 96 polyp surveillance(51.6%),42 lower gastrointestinal symptoms(22.6%),28 due to incomplete colonoscopy(15%),18 anaemia(9.7%)and 2 inflammatory bowel disease surveillance(1.1%).overall,CCE completion was 77%(144/186),image quality was adequate/diagnostic in 91%(170/186),mean colonic transit time was 3.5 h(0.25-13),and the polyp detection rate was 57%(106/186).Completion rates wer

关键词： Castor oil Colon capsule endoscopy Bowel preparation Completion rates Excretion rates