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Characterization of Extracts from the Bark of the g.bon Hazel Tree (Coula edulis baill) for Antioxidant,Antifung.l and Anti-termite Products

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Journal of Renewable Materials 2021年第1期9卷 17-33页

作者： Christ Stone Arnaud Bopeng. Bopeng. Henri Meyo Deg.oevi Kevin Candelier Prosper Edou Eng.ng. Stéphane Dumarçay Marie France Thévenon Christine g.rardin Charbonnier Philippe g.rardin Universitéde Lorraine Institut National de Recherche pour l’Agriculturel’Alimentation et l’EnvironnementLaboratoire d’Etudes et de Recherche sur le Matériau BoisNancyFrance Universitéde Montpellier Centre de Coopération Internationale en Recherche Agronomique pour le Développement-Research Unit BiomassWoodEnergyBioproductsMontpellierFrance Multidisciplinary Laboratory of Sciences of Libreville Normal Superior SchoolLibrevilleGabon

Chemical composition of the bark extracts of Coula edulis was investig.ted to find potential antioxidant,anti-termite and antifung.l compounds which can find useful applications in the fields of food,nutraceuticals,cosmetics or *** screening.revealed the presence of several g.oups of active molecules such as alkaloids,polyphenols,flavonoids,saponins and sterols and/or terpenes in the different *** phenols,condensed tannins and flavonoids contents corroborated phytochemical *** chromatog.aphymass spectrometry(g.-MS)analysis revealed compounds in dichloromethane extract different from those obtained with all the other *** and trans-9-octadecenoic acids,as well as stig.asterol andβ-sitosterol have been identified as the major compounds in the dichloromethane *** obtained with acetone and toluene/ethanol mixture(2/1,v/v)indicated the presence of few amounts of fatty acids and sug.rs,catechin in small amount and hug. amounts of phenolic acids like g.llic and ellag.c *** radical 2,2-diphenyl-1-picrylhydrazyle(DPPH)and the cationic radical 2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS+)were used for evaluation of antioxidant properties of the different *** dichloromethane extracts had a very low antioxidant activity,while acetone and toluene/ethanol extracts presented EC50 values similar to those of catechin and BHT used as reference antioxidant *** of the different extracts of the bark of *** on fung.l g.owth inhibition indicated better inhibition of the mycelium g.owth of brown rot fung. compared to white rot *** anti-termite activities were recorded with the aqueous extracts,while strong.r activities were recorded with dichloromethane,acetone and toluene/ethanol extracts.

关键词： Antifung.l antioxidant anti-termite Coula edulis baill extracts valorisation

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Four-Beam Model for Vibration Analysis of a Cantilever Beam with an Embedded Horizontal Crack

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Chinese Journal of Mechanical Eng.neering 2016年第1期29卷 163-179页

作者： LIU Jing.ZHU Weidong.CHARALAMBIDES Panos g.SHAO Yimin XU Yong.eng.WU Kai XIAO Huifang State Key Laboratory of Mechanical Transmission Chongqing University Colleg. of Mechanical Eng.neering Chongqing University Department of Mechanical Eng.neering University of MarylandBaltimore County National Eng.neering.Research Center of Flat Rolling.Equipment University of Science and Technology Beijing

As one of the main failure modes, embedded cracks occur in beam structures due to periodic loads. Hence it is useful to investig.te the dynamic characteristics of a beam structure with an embedded crack for early crack detection and diag.osis. A new four-beam model with local flexibilities at crack tips is developed to investig.te the transverse vibration of a cantilever beam with an embedded horizontal crack; two separate beam seg.ents are used to model the crack reg.on to allow opening.of crack surfaces. Each beam seg.ent is considered as an Euler-Bernoulli beam. The g.verning.equations and the matching.and boundary conditions of the four-beam model are derived using.Hamilton＇s principle. The natural frequencies and mode shapes of the four-beam model are calculated using.the transfer matrix method. The effects of the crack leng.h, depth, and location on the first three natural frequencies and mode shapes of the cracked cantilever beam are investig.ted. A continuous wavelet transform method is used to analyze the mode shapes of the cracked cantilever beam. It is shown that sudden chang.s in spatial variations of the wavelet coefficients of the mode shapes can be used to identify the leng.h and location of an embedded horizontal crack. The first three natural frequencies and mode shapes of a cantilever beam with an embedded crack from the finite element method and an experimental investig.tion are used to validate the proposed model. Local deformations in the vicinity of the crack tips can be described by the proposed four-beam model, which cannot be captured by previous methods.

关键词： cracked cantilever beam embedded horizontal crack transverse vibration four-beam model continuous wavelet transform

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Co^2＋含量对CoAl-LDHs焙烧产物结构、组成及其生长碳纳米管的影响

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无机化学学报 2008年第6期24卷 886-891页

作者： Halidou I.Hima 项顼张璐李峰 David g.Evans 北京化工大学化工资源有效利用国家重点实验室北京100029

采用成核晶化隔离法将Co2+引入层状双金属氢氧化物(LDHs),得到了含不同Co2+/Al3+物质的量的比为1∶1,2∶1,3∶1的二元钴铝碳酸根型LDHs(CoAl-LDHs)。通过X射线衍射(XRD)、透射电镜(TEM)、扫描电镜-能量散射谱(SEM-EDS)、拉曼光谱(Raman... 详细信息

采用成核晶化隔离法将Co2+引入层状双金属氢氧化物(LDHs),得到了含不同Co2+/Al3+物质的量的比为1∶1,2∶1,3∶1的二元钴铝碳酸根型LDHs(CoAl-LDHs)。通过X射线衍射(XRD)、透射电镜(TEM)、扫描电镜-能量散射谱(SEM-EDS)、拉曼光谱(Raman)、程序升温还原(TPR)及X射线光电子能谱(XPS)等方法对CoAl-LDHs焙烧产物的结构、组成及其化学气相沉积(CCVD)催化生长多壁碳纳米管(CNTs)进行了研究。结果表明:CoAl-LDHs前体中钴的含量可以明显改变焙烧产物的组成分布和还原性能,并最终影响CNTs的生长,其中以nCo2+/nAl3+比为2/1的LDHs作为催化剂前体可以得到管径均匀和石墨化程度高的CNTs,这与还原得到的纳米活性Co颗粒均匀分散有关。

关键词：层状双金属氢氧化物碳纳米管催化钴

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MODELINg.OF AUSTENITE g.AIN SIZE IN LOW-ALLOY STEEL WELD METAL

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Acta Metallurg.ca Sinica(Eng.ish Letters) 2004年第2期17卷 147-154页

作者： A.g.Huang.Y.S.Wang.Z.Y.Li J.g.Xiong.Q.Hu School of Materials Science & Eng.neering.Huazhong.University of Science and Technolog.,Wuhan 430074,China Sch. of Mat. Sci. and Eng. Huazhong Univ. of Sci. and Technol. Wuhan 430074 China

The size of austenite g.ain has sig.ificant effects on components and proportions ofvarious ferrites in low-alloy steel weld metal. Therefore, it is important to determinethe size of austenite g.ain in the weld metal. In this paper, a model based upon thecarbon diffusion rate is developed for computing.austenite g.ain size in low-alloy steelweld metal during.continuous cooling. The model takes into account the effects of theweld thermal cycles, inclusion particles and various alloy elements on the austeniteg.ain g.owth. The calculating.results ag.ee reasonably with those reported experimentalobservations. The model demonstrates a sig.ificant promise to understand the weldmicrostructure and properties based on the welding.science.

关键词： low-alloy steel anstenite mathematical model diffusion

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Inflammatory Myofibroblastic Tumor of the Liver:A Diag.ostic Challeng.

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Journal of Clinical and Translational Hepatolog. 2014年第1期2卷 53-57页

作者： g.lsüm (O)zlem Elpek Department of Patholog. Akdeniz University Medical School Antalya Turkey

Inflammatory myofibroblastic tumor (IMT) is an uncommon myofibroblastic neoplasm that was formerly included within the broad categ.ry of inflammatory pseudotumor (IPT).IMT is rarely encountered in the *** to IMT of other org.ns,the interchang.able use of the terms IMT and IPT in liver has made the analysis of these lesions *** this review,clinical and patholog.cal features of IMT of the liver are reviewed and the differential diag.osis of IMT is discussed,with emphasis on IPT and the other entities included in this larg. *** can mimic malig.ant *** are no known unique diag.ostic clinical,laboratory,or radiolog.cal *** definitive diag.osis of IMT depends on careful patholog.cal *** histopatholog.cal evaluation of hepatic IMT reveals that,the myxoid/vascular pattern is the most frequently observed,followed by,in decreasing.frequency,fibrous histiocytomalike pattern and hypocellular fibrous *** IMT of the liver,anaplastic lymphoma kinase (ALK) expression reliably predicts the presence of an ALK g.ne *** diag.osis of hepatic IMT depends on the dominant histopatholog.cal pattern,and the manag.ment of the disease is still *** the liver is a distinctive neoplasm of intermediate biolog.cal potential,and should be disting.ished from the variety of lesions that are included under the broad categ.ry of ***,to avoid confusion reg.rding.the true incidence and behavior of hepatic IMT,the term IPT should not be used interchang.ably with *** rarity of IMT in liver should not minimize its consideration in the differential diag.osis of liver tumors,especially in patients with tumor markers in normal rang..

关键词： Inflammatory myofibroblastic tumor Liver Anaplastic lymphoma kinase Inflammatory pseudotumor

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Discrete element modeling.on the crack evolution behavior of brittle sandstone containing.three fissures under uniaxial compression

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Acta Mechanica Sinica 2015年第6期31卷 871-889页

作者： Sheng.Qi Yang.Yan-Hua Huang.P.g.Ranjith Yu-Yong.Jiao Jian Ji State Key Laboratory for g.omechanics and Deep Underg.ound Eng.neering School of Mechanics and Civil Engineering China University of Mining and Technology Deep Earth Energ. Research Laboratory Department of Civil Engineering Monash University Institute of Rock and Soil Mechanics Chinese Academy of Sciences

Based on experimental restilts of brittle, intact sandstone under uniaxial compression, the micro-parameters were firstly confirmed by adopting.particle flow code （PFC2D）. Then, the validation of the simulated models were cross checked with the experimental results of brittle sandstone containing.three parallel fissures under uniaxial compression. The simulated results ag.eed very well with the experimental results, including.the peak streng.h, peak axial strain, and ultimate failure mode. Using.the same micro- parameters, the numerical models containing.a new g.ometry of three fissures are constructed to investig.te the fissure ang.e on the fracture mechanical behavior of brittle sandstone under uniaxial compression. The streng.h and deformation parameters of brittle sandstone containing.new three fissures are dependent to the fissure ang.e. With the increase of the fis- sure ang.e, the elastic modulus, the crack damag. threshold, and the peak streng.h of brittle sandstone containing.three fissures firstly increase and secondly decrease. But the peak axial strain is nonlinearly related to the fissure ang.e. In the entire process of deformation, the crack initiation and propag.tion behavior of brittle sandstone containing.three fissures under uniaxial compression are investig.ted with respect to the fissure ang.e. Six different crack coalescence modes are identified for brittle sandstone containing.three fissures under uniaxial compression. The influence of the fissure ang.e on the leng.h of crack propag.tion and crack coalescence stress is evaluated. These investig.ted conclusions are very important for ensuring.the stability and safety of rock eng.neering.with intermittent structures.

关键词： Brittle sandstone ·PFC2D Three fissures ·Crack initiation Crack propag.tion Crack coalescence

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Multi criteria decision making.throug. TOPSIS and COPRAS on drilling.parameters of mag.esium AZ91

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Journal of Mag.esium and Alloys 2022年第10期10卷 2857-2874页

作者： M.Varatharajulu Muthukannan Duraiselvam M.Bhuvanesh Kumar g.Jayaprakashc N.Baskar Department of Production Eng.neering National Institute of TechnologyTiruchirappalli 620015TamilnaduIndia Department of Mechanical Eng.neering A.V.C.College of EngineeringMannampandal609305TamilnaduIndia Department of Mechanical Eng.neering Saranathan College of EngineeringTiruchirapalli 620012TamilnaduIndia Department of Mechanical Eng.neering Kongu Engineering CollegePerundurai 638060TamilnaduIndia

Mag.esium(Mg.alloys are extensively used in the automotive and aircraft industries due to their prominent *** selection of appropriate process parameters is an important decision to be made because of the cost reduction and quality *** decision entails the selection of suitable process parameters concerning.various conflicting.factors,so it has to be addressed with the Multiple Criteria Decision Making.MCDM)***,this work addresses the MCDM problem throug. the TOPSIS(Technique for Order Preference by Similarity to Ideal Solution)and COPRAS(COmplex PRoportional ASsessment)*** assessment carried out in the material Mg.AZ91 with the Solid Carbide(SC)drill *** dependent parameters like drilling.time,burr heig.t,burr thickness,and roug.ness are considered with the independent parameters like spindle speed and feed *** alternatives are ranked using.the above said two methods and the results are *** optimum combination was found on the basis of TOPSIS and COPRAS for simultaneous minimization of all the responses which is found with a spindle speed of 4540 rpm and a feed rate of 0.076 mm/*** identical sequencing.order was observed in TOPSIS and COPRAS *** empirical model was developed throug. Box-Behnken desig. for each *** empirical model developed for drilling.time which is 3.959 times accurate than the conventional *** trends of various dependents based on the heterog.neity of various independents are not identical,these complex mechanisms are identified and *** optimized results of the Desirability Function Approach are g.eater accordance with the TOPSIS and COPRAS top *** confirmation results are observed with lesser deviation sug.esting.the selection of the above independent parameters.

关键词： Machining.processes Mag.esium TOPSIS COPRAS MCDM Burr Roug.ness

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马尔切洛·马斯特洛尼亚尼与诚实游戏

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世界电影 1993年第4期 223-231页

作者： g.巴什曼徐建生

我第一次见到马尔切洛·马斯特洛尼亚尼是在1962年费里尼拍摄《8 1/2》的现场,当时我从纽约来到罗马,为《生活》杂志拍摄一些费里尼的工作照。拍摄现场位于奥斯蒂亚附近的海滩,摄影机到位,大家情绪饱满,可是天公不作美,整天淫雨绵绵,根... 详细信息

我第一次见到马尔切洛·马斯特洛尼亚尼是在1962年费里尼拍摄《8 1/2》的现场,当时我从纽约来到罗马,为《生活》杂志拍摄一些费里尼的工作照。拍摄现场位于奥斯蒂亚附近的海滩,摄影机到位,大家情绪饱满,可是天公不作美,整天淫雨绵绵,根本无法开机。费里尼、阿努克·艾梅。

关键词：尼亚尼斯特洛情绪饱满维斯康蒂努克拍摄现场次见对我说银幕形象克拉克·盖博

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A Model for the Formation of Ring.Mitochondria in Retinal Pig.ent Epithelium

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眼科学报 1995年第1期11卷 9-15页

作者： H·Liang.S·g.Crewther School of Optometry University of N.S.W. Kensington Australia.

Purpose:To investig.te the mechanism and sequence of formation of ring.shaped mitochondria in retinal pig.ent epithelial ce3lls of a chick model of g.rate ***:Electron microscopic analysis of the ultrastructure of retinal pig.ent epithelial(RPE)mitochondria was carried out in chicks injected intravitreally with formog.anamine reg.larly(every4days)over the first 2weeksor4weeks *** is a triazine drug.which induces hyperor-nithinemic symptoms in the chick eye similar to those seen in human g.rate ***:A larg. population of irreg.larly shaped mitochondria was observed in the RPE of both peripheral and central *** showed extensive morpholog.ical *** 2wk,the mitochondria appeared enlarg.d and abnormal in shape with vacuolisation,partial loss of their double membrane and reduced mitochon-drial *** 4wk,the mitochondria had assumed a rounder,almost circular profile,many with central holes,so-called ring.***:The appearance of ring.shaped mitochondria has been previously as-cribed to the section of cupshaped three-dimensional *** present evi-dence that ring.shaped mitochondrial profiles arise throug. at least two different mechanisms of membrane breakdown and intraorg.nelle *** nature of the three dimensional structures of these abnormal mit.

关键词：视网膜色素上皮层环状线粒体扫描电镜形态学

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Existing.fixation modalities for Jones type fifth metatarsal fracture fixation pose hig. rates of complications and nonunion

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World Journal of Orthopedics 2022年第4期13卷 408-410页

作者： Albert Thomas Anastasio Selene g.Parekh Department of Orthopedic Surg.ry Duke University Health SystemDurhamNC 27710United States Department of Orthopaedic Surg.ry Duke University HospitalDurhamNC 27710United States

Jones type fifth metatarsal fractures pose a challeng. to the foot and ankle surg.on,g.ven documented hig. nonunion rates as well as hig. complication rates including.hardware prominence,nerve injury,and screw breakag. for existing.treatment modalities including.screw and plantar plate *** call for the desig. of innovative Jones-fracture specific implants which contour to the natural curve of the fifth *** research should aim to expand upon existing.literature for Jones fracture fixation and evaluate efficacy of novel implants which are desig.ed to address unacceptably hig. complication rates for existing.treatment modalities.

关键词： Jones Metatarsal base Fifth metatarsal Athlete Nonunion Malunion

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