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Production and characterization of ZnO nanoparticles and porous particles by ultrasonic spray pyrolysis using a zinc nitrate precursor

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 651-656页

作者： Burak Ebin Elif Arτg Burak zkal Sebahattin Gürmen Metallurgical & Materials Engineering Department Istanbul Technical University

ZnO nanoparticles and porous particles were produced by an ultrasonic spray pyrolysis method using a zinc nitrate precursor at various temperatures under air atmosphere. The effects of reaction temperature on the size and morphology of ZnO particles were investi- gated. The samples were characterized by energy dispersive spectroscopy, X-ray diffraction, transmission electron microscopy, and scanning electron microscopy. ZnO particles were obtained in a hexagonal crystal structure and the crystallite shapes changed from spherical to hex- agonal by elevating the reaction temperature. The crystallite size grew by increasing the temperature, in spite of reducing the residence time in the heated zone. ZnO nanoparticles were obtained at the lowest reaction temperature and ZnO porous particles, formed by aggregation of ZnO nanoparticles due to effective sintering, were prepared at higher temperatures. The results showed that the properties of ZnO particles can be controlled by changing the reaction temperature in the ultrasonic spray pyrolysis method.

关键词： zinc oxide nanoparticles nanocrystallites porous materials ultrasonic applications spray pyrolysis

Preliminary pharmacological evaluation of Martynia annua Linn leaves for wound healing

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Asian Pacific Journal of Tropical Biomedicine 2011年第6期1卷 421-427页

作者： Santram Lodhi Singhai ak Department of Pharmaceutical Sciences Dr.H.S.Gour University SAGAR(M.P.)

Objective:To evaluate the wound healing potential of fractions from ethanol extract of Martynin annua(***) Linn ***:Ethanol extract of *** Linn leaves was fractionate into three different fractions(MAF-A,MAF-B and MAF-C) which were screened for wound healing potential using two models:excision and incision on *** thin layer chromatography(TLC) profile of all fractions were analysed and TLC of luteolin was also *** PovidoneIodine Ointment was used as reference for *** and incision wounds were created on dorsal portion of rats for *** contraction,biochemical parameters(protein level and hydroxyproline level) and histopathological study were performed in excision wound model whereas incision model was used for determination of tensile ***:The wound contraction and tensile strength of skin tissues were observed significantly greater in MAF-C fraction treated group than other two fractions(Pn excision wound method(on day 18) protein content and hydroxyproline were found significantly higher in MAF-C group than control group(Pngiogenesis,matured collagen fibres and fibroblast cells as compared with the control ***:In conclusion, our findings suggest that fiaction MAF-C from ethanol extract of *** leaves is found most effective in wound healing.

关键词： Martynia annua Wound healing Povidone-iodine ointment Incision Excision Luteolin TLC Wound contraction Tensile strength

new insights into the coagulopathy of liver disease and liver transplantation

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World Journal of Gastroenterology 2006年第48期12卷 7725-7736页

作者： M Senzolo P Burra E Cholongitas ak Burroughs Gastroenterology Department of Surgical and Gastroenterological Sciences University Hospital of Padua Padua ItalyLiver Transplantation and Hepatobiliary Unit Royal Free Hospital London United Kingdom Gastroenterology Department of Surgical and Gastroenterological Sciences University Hospital of Padua Padua Italy Liver Transplantation and Hepatobiliary Unit Royal Free Hospital London United Kingdom

The liver is an essential player in the pathway of coagulation in both primary and secondary haernostasis. Only yon Willebrand factor is not synthetised by the liver, thus liver failure is associated with impairment of coagulation. However, recently it has been shown that the delicate balance between pro and antithrornbotic factors synthetised by the liver might be reset to a lower level in patients with chronic liver disease. Therefore, these patients might not be really anticoagulated in stable condition and bleeding may be caused only when additional factors, such as infections, supervene. Portal hypertension plays an important role in coagulopathy in liver disease, reducing the number of circulating platelets, but platelet function and secretion of thrornbopoietin have been also shown to be impaired in patients with liver disease. Vitamin K deficiency may coexist, so that abnormal clotting factors are produced due to lack of gamma carboxylation. Moreover during liver failure, there is a reduced capacity to clear activated haernostatic proteins and protein inhibitor complexes from the circulation. Usually therapy for coagulation disorders in liver disease is needed only during bleeding or before invasive procedures. When end stage liver disease occurs, liver transplantation is the only treatment available, which can restore normal haemostasis, and correct genetic clotting defects, such as haemophilia or factor V Leiden mutation. During liver transplantation haemorrage may occur due to the pre-existing hypocoagulable state, the collateral circulation caused by portal hypertension and increased fibrinolysis which occurs during this surgery.

关键词： Coagulation Cirrhosis Liver transplantation

Magnetocaloric properties of the Gd_5Si_(2.05-x)Ge_(1.95-x)Mn_(2x) compounds

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Journal of Rare Earths 2010年第3期28卷 477-480页

作者： E.Yüzüak I.Dincer Y.Elerman Ankara University Faculty of EngineeringDepartment of Engineering Physics

The influence of the manganese-alloying on the structure and magnetocaloric properties of the Gd5Si2.05Ge1.95 compound was studied by X-ray powder diffraction and magnetization *** Gd5Si2.05-xGe1.95-xMn2x(2x=0,0.03 and 0.08) compounds crystallized in the Gd5Si2Ge2-type monoclinic *** all X-ray powder diffraction patterns,a minor hexagonal Gd5Si3 phase was observed as a second *** increasing Mn content,the unit cell volume *** the compounds with x=0,0.03 and 0.08,the fi...

关键词： magnetic materials heat treatments intermetallics rare earths

Effects of manganese doping on magnetocaloric effect in Ge-rich Gd_5Ge_(2.05)Si_(1.95) alloy

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Journal of Rare Earths 2012年第3期30卷 217-221页

作者： E.Yüzüak I.Dincer Y.Elerman Department of Engineering Physics Faculty of EngineeringAnkara University

The structure, magnetic and magnetocaloric properties of the Ge-rich Gd5Ge2.05-xSi1.95-xMn2x （x=0.01 and 0.03） alloys were investigated by scanning electron microscopy, X-ray powder diffraction, differential scanning calorimeter （DSC） and magnetization measurements. The results of energy dispersive X-ray analysis （EDX） and X-ray diffraction analyses showed that the composition and crystal structure of the alloys were desired. DSC measurements were performed to determine the transformation temperatures for each alloy. Both alloys exhibited the first order phase transition around room temperature. The alloys showed an anti-ferromagnetic transition around 60 K. The isothermal magnetic entropy changes of the alloys were determined from the isothermal magnetization measurements by using the Maxwell relation. The maximum values of isothermal magnetic entropy change of the Gd5Ge2.05-xSi1.95-xMn2x alloy with x=0.01 was found to be -12.1 and -19.8 J/（kg·K） using Maxwell equation around 268 K in applied fields of 2 and 5 T, respectively.

关键词： magnetocaloric effect entropy change magnetic materials rare earths

Mechanical Properties of Reactive Powder Concretes Produced Using Pumice Powder

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Journal of Wuhan University of Technology(Materials Science) 2019年第2期34卷 353-360页

作者： Abdurrezzak BakIS Ercan ISIK Alev ak?ll? EL Mustafa üLKER Bitlis Eren University Faculty of Engineering and Architecture Department of Civil Engineering Bitlis Eren University Vocational School of Technical Sciences

We examined the applicability of the pumice aggregate on the concrete formed by considering the reactive powder concrete mixture ratios, for the rigid superstructure concrete road pavement and building construction. The natural pumice aggregate in fibrous and non-fibrous concrete samples was used in the production of concrete by fracturing in 0.1-0.6 mm dimensions in rotor mill. The concreted formed in this way is named after the pumice powder concrete(PPC). The PPC samples produced were taken 7 days as 20 ℃ standard water cure, 28 days as 20 ℃ standard cure and 9 different types of combined cures. The combined cures were applied different temperatures in different durations. PPC samples were subjected to some pressure and flexural tests at the end of the standard water and combined cures. The highest compressive and flexural strengths of PPC samples were obtained after the combined cures: 3 days in 20 ℃ as standard water curing + 2 days in 180 ℃ in drying-oven. The highest compressive strength of PPC samples without any fiber was found to be 47.27 MPa, as for the highest flexural strength, it is found to be 5.23 MPa, in the end of the study. The highest compressive strength of fibrous PPC samples was 51.12 MPa, while flexural strength was 6.57 MPa.

关键词： reactive powder concrete (RPC) pumice powder concrete (PPC) combined cure compressive strength flexural strength

Effect of nano Clay Reinforcement on Thermal Conductivity of Epoxy/CnT Composite Material

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Journal of Materials Science and Chemical Engineering 2023年第12期11卷 1-9页

作者： Yelda akçin Ergün Melih Özçatal Department of Metallurgical and Materials Engineering Faculty of Technology Afyon Kocatepe University Afyonkarahisar Türkiye Department of Mechatronics Engineering Faculty of Technology Afyon Kocatepe University Afyonkarahisar Türkiye

Epoxy is one of the most important polymers preferred in various technological applications thanks to its good mechanical properties and lightness. However, their low thermal conductivity limits their usage areas. Increasing the thermal conductivity of epoxy is an important research topic. One of the most ideal ways to achieve this is to improve the thermal conductivity of epoxy without increasing its weight, thanks to nanoparticles. Carbon nanotubes (CnT) and clays are among the materials used for this purpose. In this study, the thermal conductivities of hybrid polymer composites reinforced separately and together in an epoxy matrix were investigated. The aim of the study is to find out how CnT and nano clay affect the thermal conductivity of the epoxy matrix, separately and together, and reveal the synergistic effect of these nanoparticles.

关键词： Epoxy Carbon nanotube nano Clay Thermal Conductivity

Petrogenesis of the ükapili Granitoid and its Mafic Enclaves in Elmal Area (nigde, Central Anatolia, Turkey)

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Acta Geologica Sinica(English Edition) 2013年第3期87卷 738-748页

作者： Hüseyin KURT Kerim KOak Kürsad ASAn Mustafa KARakAS Department of Geological Engineering Seluk University Central Anatolia Directorate of Mineral Research and Exploration

The Late Cretaceous Uckapth Granitoid including mafic microgranular enclaves intruded into metapelitic and metabasic rocks, and overlain unconformably by neogene ignimbrites in the ni^de area of Turkey. It is mostly granite and minor granodiorite in composition, whereas its enclaves are dominantly gabbro with a few diorites in composition. The Uckapdl Granitoid is composed mainly of quartz, K-feldspar, plagioclase, biotite, muscovite and minor amphibole while its enclaves contain mostly plagioclase, amphibole, minor pyroxene and biotite. The Uckapth Granitoid has calcalkaline and peraluminous （AJCnK= 1.0-1.3） geochemical characteristics. It is characterized by high LILE/HFSE and LREE/HREE ratios （（La/Lu）n 3-33）, and has negative Ba, Ta, nb and Eu anomalies, resembling those of comsion granitoids. The {）fkaplh Granitoid has relatively high STSr/S6Sr0） ratios （0.711189--0.716061） and low end（t） values （-5.13 to -7.13）, confirming crustal melting. In contrast, the enclaves are tholeiitic and metaluminous, and slightly enriched in LILEs （K, Rb） and Th, and have negative Ta, nb and Ti anomalies; propose that they were derived from a subduction-modified mantle source. Based on mineral and whole rock chemistry data, the Uckapth granitoid is H-（hybrid） type, post-collision granitoid developed by mixing/mingllng processes between crustal melts and mantle-derived mafic magmas.

关键词： H-type granitoid mafic enclave geochemistry Central Anatolia Turkey

A Late Cretaceous ensimatic arc developed during closure of the northern branch of neo-Tethys(central-northern Turkey)

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Geoscience Frontiers 2019年第3期10卷 1015-1028页

作者： Metin Beyazpirin? Ali Ekber ak?ay Ali Yilmaz Meftun Kerem S?nmez Geological Research Department General Directorate of Mineral Research and Exploration (MTA) Department of Environmental Engineering Engineering Faculty Cumhuriyet University

Studies on differentiation of ensimatic arc units from melange units in the northern Anatolian Ophiolitic Belt(nAOB) are very rare. The study area represents the southern edge of the central part of the *** aim of the study is to distinguish the main units of nAOB and to define the geotectonic setting of the Darmik Ensimatic Arc Association(DEAA). To study the ensimatic arc units as an independent tectonic unit is important and facilitates understanding of the geological evolution of the nAOB. During field studies, the contact relationships within the Darmik Ensimatic Arc Association(DEAA) units and also with other tectonic units were reviewed. Then, paleontological, geochronological, petrological and also geochemical properties of the DEAA have been defined. In the present study, ensimatic arc units have been distinguished from ophiolitic association for the first time, in the region. As a result of the study, the DEAA is divided into two levels and lower level named as the Kartal unit and upper level named as the izibüyük unit. In the Kartal unit, basaltic and andesitic lavas with their equivalent pyroclastic rock units are dominant. Radiolarite and mudstones interbedded within the Kartal unit of DEAA have Turonian and Santonian age. In addition, the age of basalt samples of DEAA are 98.7 ± 2.4 Ma, defined using the^(40)Ar/39 Ar method. The izibüyük unit of DEAA comprises conglomerate, sandstone, claystone, mudstone,clayey limestone, micritic limestone with volcanic interbeds and also calciturbidites. Santonian-Maastrichtian ages were obtained from this unit of the DEAA. In conclusion, the age of DEAA is widely accepted as Late Cretaceous. After the evaluation of the analysis, the volcanics of the DEAA originated from calcalkaline-basalts, which reflect ensimatic arc magmatism.

关键词： north Anatolian Ophiolitic Belt Double subduction zones Darmik ensimatic arc Turkey