The Experts below are selected from a list of 114342 Experts worldwide ranked by ideXlab platform
Nongnuj Muangsin - One of the best experts on this subject based on the ideXlab platform.
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thermally stable Metal containing polyureas from hexadentate schiff Base Metal complexes and diisocyanates
Polymer Degradation and Stability, 2004Co-Authors: Nuanphun Chantarasiri, Choprayoon Chulamanee, Thussanee Mananunsap, Nongnuj MuangsinAbstract:Abstract Hexadentate Schiff Base Metal complexes were synthesized and used in the preparation of Metal-containing polyureas. Polycondensation reactions of hexadentate Schiff Base Metal complexes with diisocyanates, namely hexamethylene diisocyanate (HDI) and 4,4′-diphenylmethane diisocyanate (MDI) were performed in dichloromethane without the use of catalyst. The reaction proceeded with good yield and the polymers could be isolated by precipitation from the reaction mixture. The polymers were characterised by IR, NMR, elemental analysis, solubility and viscosity. Thermal stability and flame retardant properties of the polymers were investigated by thermogravimetric analysis in air and by measuring limiting oxygen index values.
Shoichiro Yamada - One of the best experts on this subject based on the ideXlab platform.
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advancement in stereochemical aspects of schiff Base Metal complexes
Coordination Chemistry Reviews, 1999Co-Authors: Shoichiro YamadaAbstract:Abstract The object of the paper is to look back upon the development of coordination chemistry in the past several decades, during the career of the author, and possibly see how and through what accomplishments the present coordination chemistry has been built up. For the sake of space available, the paper will focus on the stereochemical aspects of Schiff Base Metal complexes. Those findings which are remarkable from a historical point of view are chosen and discussed. There is other work I would like to include, but must omit for lack of space. The paper is divided for convenience into the two parts dealing with Schiff Base ligands of types (A) and (B): (A) Salen and multidentate ligands derived from Salen, and (B) bidentate N-substituted salicylidene-aminates. The main subjects to be discussed include: (A) non-planar Salen in Metal complexes, effects of the polymethylene chain between the two imine nitrogen atoms on the structure of Metal complexes, the first synthetic sexadentate Metal chelates, possibility of trigonal-prismatic configuration for sexadentate chelates, dioxygen adducts of Co(Salen) and analogous complexes. (B) Anomalous solution paramagnetism of Ni(II) complexes, isomerism in the Ni(II) and Cu(II) complexes with Schiff Base ligands and 5-coordination of Co(II) and Ni(II).
Jacques Besson - One of the best experts on this subject based on the ideXlab platform.
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Creep rupture of a 9Cr1MoNbV steel at 500 °C : Base Metal and welded joint
Nuclear Engineering and Design, 2010Co-Authors: Florian Vivier, Anne-françoise Gourgues-lorenzon, Jacques BessonAbstract:ASME Grade 91 steel Base Metal and a similar weld were tested under creep at 500 °C for rupture time up to 18,000 h. Creep failure of cross-weld specimens occurs in the weld Metal at this temperature. No significant microstructural changes were observed after creep. Analysis of creep deformation of smooth creep bars, welded joints and slightly notched bars indicated an apparent creep stress exponent of 19. For the creep conditions considered, failure of the material can be explained by the viscoplastic instability of the specimens without significant damage development. This allowed to develop a simple analysis for time to failure prediction.
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microstructure evolution in Base Metal and welded joint of grade 91 martensitic steels after creep at 500 600 c
ECF 17, 2008Co-Authors: Florian Vivier, Clara Panait, Annefrancoise Gourgueslorenzon, Jacques BessonAbstract:The microstructure of grade 91 Base Metal after long term creep exposure at 600°C and after short-term exposure at 500°C was examined....
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Microstructure evolution in Base Metal and welded joint of Grade 91 martensitic steels after creep at 500-600°C
2008Co-Authors: Florian Vivier, Clara Panait, Anne-françoise Gourgues-lorenzon, Jacques BessonAbstract:The microstructure of grade 91 Base Metal after long term creep exposure at 600°C and after short-term exposure at 500°C was examined....
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High temperature creep flow and damage properties of 9CrMoNbV steels : Base Metal and weldment
Nuclear Engineering and Design, 2005Co-Authors: Vincent Gaffard, Anne-françoise Gourgues-lorenzon, Jacques BessonAbstract:High temperature creep flow and damage properties of 9Cr1MoNbV steel and weldment are investigated in the present study. First, an experimental dataBase is built to compare both creep flow and damage properties of the Base Metal and the weldment. Metallurgical investigations before and after creep tests revealed that the microstructural state is responsible for the lower creep strength in the weldment. A simple analysis Based on the description of the steady-state creep stage and on use of empirical lifetime prediction relationships is performed. It allows to predict the weldment creep lifetime without performing an extensive number of experiments.
Nuanphun Chantarasiri - One of the best experts on this subject based on the ideXlab platform.
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thermally stable Metal containing polyureas from hexadentate schiff Base Metal complexes and diisocyanates
Polymer Degradation and Stability, 2004Co-Authors: Nuanphun Chantarasiri, Choprayoon Chulamanee, Thussanee Mananunsap, Nongnuj MuangsinAbstract:Abstract Hexadentate Schiff Base Metal complexes were synthesized and used in the preparation of Metal-containing polyureas. Polycondensation reactions of hexadentate Schiff Base Metal complexes with diisocyanates, namely hexamethylene diisocyanate (HDI) and 4,4′-diphenylmethane diisocyanate (MDI) were performed in dichloromethane without the use of catalyst. The reaction proceeded with good yield and the polymers could be isolated by precipitation from the reaction mixture. The polymers were characterised by IR, NMR, elemental analysis, solubility and viscosity. Thermal stability and flame retardant properties of the polymers were investigated by thermogravimetric analysis in air and by measuring limiting oxygen index values.
Tugrul Kirtiloglu - One of the best experts on this subject based on the ideXlab platform.
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Effects of Er:YAG laser treatments on surface roughness of Base Metal alloys
Lasers in Medical Science, 2012Co-Authors: Göknil Ergün Kunt, Ahmet Umut Güler, Gözlem Ceylan, İbrahim Duran, Pelin Özkan, Tugrul KirtilogluAbstract:We investigated the effects of different Er:YAG laser treatments on the surface roughness of Base Metal alloys. A total of 36 specimens were prepared of two Base Metal alloys (Wiron 99, Bellabond plus). The surfaces of the specimens were standardized by gradual wet grinding with 320-, 600-, 800- and 1,000-grit silicon carbide paper for 10 s each on a grinding machine at 300 rpm. Specimens of each alloy were randomly divided into six groups ( n = 6) comprising a control group (group C), a group sandblasted with Al_2O_3 powder at 60 psi for 10 s through a nozzle at a distance of 10 mm (group S), and four Er:YAG laser (Fotona AT) treatment groups. The laser treatment groups were as follows: 500 mJ, 10 Hz, 100 μs (group 500MSP); 500 mJ, 10 Hz, 300 μs (group 500SP); 400 mJ, 10 Hz, 100 μs (group 400MSP); and 400 mJ, 10 Hz, 300 μs (group 400SP). Surface roughness measurements (Ra) were performed using a profilometer. The data were analysed by two-way ANOVA, and mean values were compared using Tukey’s HSD test (α = 0.05). According to the two-way ANOVA results, the Base Metal alloys and interaction between Base Metal alloy and surface treatment were not statistically significant different ( p > 0.05), the surface treatments were significantly different ( p
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Effects of Er:YAG laser treatments on surface roughness of Base Metal alloys.
Lasers in Medical Science, 2010Co-Authors: Göknil Ergün Kunt, Ahmet Umut Güler, Gözlem Ceylan, İbrahim Duran, Pelin Özkan, Tugrul KirtilogluAbstract:We investigated the effects of different Er:YAG laser treatments on the surface roughness of Base Metal alloys. A total of 36 specimens were prepared of two Base Metal alloys (Wiron 99, Bellabond plus). The surfaces of the specimens were standardized by gradual wet grinding with 320-, 600-, 800- and 1,000-grit silicon carbide paper for 10 s each on a grinding machine at 300 rpm. Specimens of each alloy were randomly divided into six groups (n = 6) comprising a control group (group C), a group sandblasted with Al2O3 powder at 60 psi for 10 s through a nozzle at a distance of 10 mm (group S), and four Er:YAG laser (Fotona AT) treatment groups. The laser treatment groups were as follows: 500 mJ, 10 Hz, 100 μs (group 500MSP); 500 mJ, 10 Hz, 300 μs (group 500SP); 400 mJ, 10 Hz, 100 μs (group 400MSP); and 400 mJ, 10 Hz, 300 μs (group 400SP). Surface roughness measurements (Ra) were performed using a profilometer. The data were analysed by two-way ANOVA, and mean values were compared using Tukey’s HSD test (α = 0.05). According to the two-way ANOVA results, the Base Metal alloys and interaction between Base Metal alloy and surface treatment were not statistically significant different (p > 0.05), the surface treatments were significantly different (p < 0.0001). For the two Base Metal alloy groups, no significant differences were observed among the control, 400MSP, and 400SP groups (p = 0.912), and these groups demonstrated the lowest Ra values. The highest Ra value was observed in group S (p < 0.05). Er:YAG laser treatment at 400 and 500 mJ/10 Hz is not an alternative method for surface roughening of Base Metal alloys.
