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Abstracts of Chinese Geological Literature 2014年第3期30卷 90-93页

20141609 Chen Guiying(College of Earth Sciences,Guilin University of Technology,Guilin 541004,China);Han Nairen New Materials of Stylophora from the Upper Cambrian of the Jingxi Area,Guangxi,South China(Acta Palaeonto... 详细信息

关键词： Cambrian Upper Paleozoic Henan Ordovician caudal f

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Semiquantitative Approach to Amyloid Positron Emission Tomography Interpretation in Clinical Practice

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World Journal of Nuclear Medicine 2022年第1期22卷 015-021页

作者： Ana M. franceschi David R. Petrover Luca Giliberto Sean A. P. Clouston Marc L. Gordon Neuroradiology Section Department of Radiology Lenox Hill Hospital Donald and Barbara Zucker School of Medicine at Hofstra/Northwell New York New York United States Institute for Neurology and Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/Northwell Manhasset New York United States Litwin-Zucker Research Center Feinstein Institutes for Medical Research Northwell Health New York United States Department of Family Population and Preventative Medicine and Program in Public Health Renaissance School of Medicine at Stony Brook University Stony Brook New York United States Departments of Neurology and Psychiatry Donald and Barbara Zucker School of Medicine at Hofstra/Northwell New York United States

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Performance evaluation of surface texturing on carbide tool under minimum quantity lubrication turning of aluminium alloy Al6061 using canola oil

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Materials Today: Proceedings 2023年

作者： Narinder Singh Gyanendra Goindi Mechanical Engineering Department Chandigarh University Mohali Punjab India

Turning operation is considered an important material removal process and its performance depends largely on the machining parameters. This study presents the analysis of the effect of surface texturing on tool during MQL turning of Aluminium alloy Al6061 using canola oil. Minimum quantity lubrication possesses the benefits of flood lubrication as well as dry machining. Canola oil used in this study possesses good lubrication properties and its kinematic viscosity is 41 mm 2 /s at 40 °C. Tool texturing is in growing trend in the manufacturing industry and it has gained the attention of many researchers in the past few years. In this study parallel textured pattern is used in which the grooves are perpendicular to chip flow direction. Average surface roughness (R a) and tangential cutting forces (f t ) are the responses measured. Chip patterns are also examined under different conditions. It is concluded that high spindle speed of 160 m/min along with low feeding rate of 0.2 mm/rev with MQL system using textured tool generates better results for tangential cutting force as well as average surface roughness in contrast with other machining conditions.

关键词： MQL Textured tool Canola oil Average surface roughness Tangential cutting force MQL Minimum quantity lubrication R a Average surface roughness f.R feed rate f t Tangential cutting force

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Experimental characterization of unidirectional carbon – Carbon composite laminate

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Materials Today: Proceedings 2023年

作者： Mohd Mohinoddin S. Irfan Sadaq Syeda Romana V. Suvarna Kumar Mechanical Engineering Department Muffakham Jah College of Engineering & Technology Hyderabad Telangana 500034 India

Advanced polymeric Composites have wide applications in various industrial sectors of Missile System, Automobile, and Space Structures have been sound prominent and endlessly receiving the wide awareness for many industries. The structural engineer desires to be eminent with the belongings of the composite material structures. The performance of fiber reinforced polymeric composite material beneath dynamic load plays a crucial task in designing such structures. In the recent work, an attempt is made to determine optimum fiber angle and the behavior of the advanced polymeric composite material, i.e., Carbon – Carbon Composites under Tensile and Compressive loads. Mechanical properties, viz., Compressive and Tensile strength are determined by using experimentation method. Hand layup technique is used for fabricating the laminates. fE Analysis (Ansys) is carried out on various fiber angles likely be [0°-90°], [30°], [45°], [60°] to validate the results which is obtained from experimentation.

关键词： Compressive Strength Tensile Strength Carbon - Carbon Composite Volume fraction (V f ) fE Analysis

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Stable soil phosphorus transformations following long-term litter manipulation in a lowland tropical forest

Soil Advances

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Soil Advances 2024年 1卷

作者： Benjamin L. Turner Aleksandra W. Bielnicka Pil Joo Kim Institute of Agriculture and Life Sciences Gyeongsang National University 501 Jinju-daero Jinju 52828 Republic of Korea Adamed Pharma S.A. ul. Mariana Adamkiewicza Czosnów 05-125 Poland Division of Applied Life Science (BK 21+ Program) Gyeongsang National University 501 Jinju-daero Jinju 52828 Republic of Korea

Productivity in tropical forests is limited by phosphorus (P) availability, but much of the P in tropical soils occurs in stable forms of limited biological availability. Phosphorus availability is therefore maintained in part by recycling from litterfall, which is susceptible to alterations through environmental change. However, the extent to which litterfall influences more stable forms of soil P remains unclear. We quantified the chemical nature of P in soils from a long-term litter manipulation experiment in lowland tropical forest in Panama, in which soils were subject to a decade of litter removal or addition. We used sequential fractionation to separate soil P into operationally defined inorganic and organic pools of contrasting stability. Labile inorganic P extracted in 0.5 M NaHCO 3 increased three-fold with litter addition, but there was no change in labile organic P, nor in moderately labile P pools extracted in 0.1 M NaOH. Surprisingly, residual (unextracted) P and stable organic P extracted in 0.25 M NaOH + 0.05 M EDTA increased strongly with litter addition and declined with litter removal. However, the distribution of P fractions as a proportion of the total P remained relatively constant. These findings show that long-term change in litterfall influences both available and stable forms of soil P in tropical forests, even though the relative distribution of P forms remains largely unchanged. The large pool of stable P in strongly weathered tropical soils has the potential to support greater long-term productivity as forests exploit the modern CO 2 -enriched atmosphere.

关键词： C carbon CO 2 carbon dioxide EDTA ethylenediaminetetraacetic acid f f statistic HCl hydrochloric acid N nitrogen NaHCO 3 sodium bicarbonate NaOH sodium hydroxide p probability P phosphorus P o organic phosphorus P t total phosphorus Sequential fractionation Tropical forests Litter manipulation Stable phosphorus

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Chemical composition and antioxidant activity of the ethanol extract and purified fractions of cadillo ( Pavonia sepioides )

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free Radicals and Antioxidants 2013年 3卷 S55-S61页

作者： Cristian A. Gasca fabio A. Cabezas Laura Torras Jaume Bastida Carles Codina Departamento de Química Grupo de Química de Compuestos Bioactivos Universidad del Cauca Popayán A.A. 304 Colombia Departament de Productes Naturals Facultat de Farmácia Universitat de Barcelona Barcelona 08028 Spain

Background Bioactive plant compounds can contribute to prevent diseases related to oxidative stress. Some of these compounds are water soluble and fat soluble vitamins, carotenoids and a huge variety of phenolic compounds associated with the antioxidant activity (AOA). Objective The aim of this study was to study the antioxidant activity of Pavonia sepioides . Methods The AOA was evaluated by spectrophotometric methods using the free radical DPPH* and the ABTS*+ radical cation assays. Total phenolic content (TPC) was determined by folin–Ciocalteu method and total flavonoid content (TfC) was determined by direct reaction with aluminum trichloride. The phenolic content was evaluated by GC/MS technique. Results The greatest antioxidant activity was found in ethyl acetate fraction (fea), The total ethanol extract (TE) showed good AOA in comparison with hexane fraction (fhx), dichloromethane fraction (fdc) and aqueous fraction (faq). The TPC and TfC analyses provided results consistent with the AOA with highest values for fea and ET respectively. Different phenolic compounds of low molecular weight were identified by GC/MS (Salicylic acid, cinnamic acid, p-hydroxybenzoic acid, p-hydroxyphenylacetic acid, p-hydrocinnamic acid, vanillic acid, gentisic acid, p-cinnamic acid, o-Cinnamic acid, protocatechuic acid, syringic acid, m-cinnamic acid, ferulic acid, and caffeic acid). These compounds could be associated with the named activity. The Pearson and Spearman association tests indicated a positive linear correlation between the AOA and TPC and TfC results, showing correlation coefficients greater than 0.810 in the Pearson test and greater than 0.700 in the Spearman test ( p < 0.05). Conclusion The AAO of P. sepioides (ET and purified fractions) was confirmed. The study provides evidence that P. sepioides is potential source of natural antioxidants showing positive correlations between phenolic contents and the AAO.

关键词： Antioxidant activity Pavonia sepioides Reactive oxygen species free radicals Oxidative stress ROS reactive oxygen species AOA antioxidant activity TPC total phenolic content TfC total flavonoid content TE total ethanol extract f ea ethyl acetate fraction f hx hexane fraction f dc dichloromethane fraction f aq aqueous fraction GC/MS gas chromatography-mass spectrometry LLE liquid-liquid extraction CE crude extract PBS phosphate buffer TEAC trolox equivalent antioxidant capacity GAE gallic acid equivalents EHSP equivalents of hesperidin r correlation coefficient EC50 effective Concentration DPPH 2,2-diphenyl-1-picrylhydrazyl BHT 3,5-di-tert-4-butylhydroxytoluene ABTS 2,20-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) Trolox 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid

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CPAffC Working Group Attends 15th African International Water Congress

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Voice of friendship 2010年第3期 36-36页

作者： Ji Yongjun,Zhang Weixiao

The impact of global warming and environmental change on the water resources available to humanity, and the threats facing future generations, was the major focus

关键词： humanity African warming climatic speakers spoke f

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The effect of slag variability in the attempted manufacture of AYf (alite-ye'elimite-ferrite) cement clinker at both laboratory and pilot scale

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CEMENT 2024年 16卷

作者： Visa Isteri Katja Ohenoja Christiane Rößler Holger Kletti Pekka Tanskanen Mirja Illikainen Theodore Hanein Timo fabritius Process metallurgy Faculty of Technology University of Oulu PO Box 4300 90014 Finland Fibre and Particle Engineering Faculty of Technology University of Oulu PO Box 4300 90014 Finland F.A. Finger Institute for Building Materials Science Bauhaus-University Weimar Coudraystr. 11 99421 Weimar Germany Manatee Consulting Limited Sheffield S3 7XL UK Department of Materials Science and Engineering The University of Sheffield Sheffield S1 3JD UK

The production of AYf (alite-ye'elimite-ferrite) clinker was tested at laboratory and semi-industrial scale using by-products from the metallurgical industry: AOD slag; ladle slag; and fayalitic slag. Alite could be produced with ye'elimite using fluorine originating from AOD (argon oxygen decarburisation) slag as a mineraliser. After a successful laboratory demonstration, the clinker production was scaled to a semi-industrial trial. It was discovered that the reason for the absence of alite formation in a semi-industrial demonstration was that the AOD slag from the specific batch did not perform the designed mineralisation effect for alite formation. This study demonstrates that alite-ye'elimite can be produced at 1260 °C at laboratory scale by using fluorine mineralisation originating from an industrial by-product – in this case, AOD slag. However, the utilisation of by-products for delicate reactions requires detailed determination of the properties of the slag, as the variability from the same source yields different clinker chemistries and mineral phases.

关键词： Calcium sulphoaluminate cement Scale-up Clinkering Waste valorisation Alite Ye'elimite Mineralisation AOD slag Cement oxide notation: C CaO S SiO 2 A Al 2 O 3 f fe 2 O 3 $ SO 3 M MgO T TiO 2

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Preface

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The Journal of Allergy and Clinical Immunology 1986年第3 PART 2期78卷 489-490页

作者： Bernstein, I.Leonard Hargreave, frederick E. Nicklas, Richard A. Reed, Charles E.

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East China Engineering Signs EPC Contracts with Yuntianhua International

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China Chemical Reporter 2008年第16期19卷 10-10页

East China Engineering Science and Technology Co.,Ltd.(SZ:0021140)announced on May 21 st that it has signed an EPC contract with Yuntianhua International Chemical Co.,*** the 200 000 t/a phosphoric acid and 100 000 t/a concentrated phosphoric acid *** is an energy conservation renovation project in Yuntianhua Red Phosphorus Co.,*** total contract valued at RMB131.18 *** Yuntianhua International and Yuntianhua Company Ltd.(SH:600096)are sub-

关键词： contract signed concentrated conservation valued f

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