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Online since: September 2010
Authors: Ágnes Bajáki, Olga Geszti, Franciska H. Karman, Hajnalka Hargitai, Ágnes Csanády, János L. Lábár
This work describes atomic-scale, crystalline structure and size distribution for noble
metal nanoparticles produced by water-based, environmental friendly technologies.
The reason for the difference can be explained by their electron structure and their high surface/volume ratio.
The size distribution, structure, morphology and the particle growth process, furthermore, the stability of the nanoparticles were investigated by several techniques, such as TEM, HRTEM, ProcessDiffraction, SEM, particle size analysis (Malvern Zetasizer).
Experimental and Discussion In-situ TEM examination of nucleation and growth of vacuum evaporated metal nanocrystals was known and successful 40 years ago, and led to the development of models, describing the structure formation of thin films [4-5].
Diffraction contrast shows that many of the large particles are polycrystalline (Large crystals in non-diffracting orientation do not show their inner structure even if they are polycrystalline).
The reason for the difference can be explained by their electron structure and their high surface/volume ratio.
The size distribution, structure, morphology and the particle growth process, furthermore, the stability of the nanoparticles were investigated by several techniques, such as TEM, HRTEM, ProcessDiffraction, SEM, particle size analysis (Malvern Zetasizer).
Experimental and Discussion In-situ TEM examination of nucleation and growth of vacuum evaporated metal nanocrystals was known and successful 40 years ago, and led to the development of models, describing the structure formation of thin films [4-5].
Diffraction contrast shows that many of the large particles are polycrystalline (Large crystals in non-diffracting orientation do not show their inner structure even if they are polycrystalline).
Online since: October 2014
Authors: Hui Guo
The crystal structure of the alloys was identified by X-ray diffraction equipment (XRD, Brookhaven, USA).
All alloys showed almost the same diffraction peaks, which indicated these alloys had the same structure.
As can in Fig.1(a), all alloys had the hexagonal CaCu5 type structure as the main crystal structure.
Generally, there is a single CaCu5 type structure in AB5 alloy, since Mg cannot be completely solid-soluted in CaCu5 type structure, part of Mg as a metastable form existed in CaCu5 type structure, and part of Mg combining with other elements (mainly Al, Mn) separated out.
Materials Chemistry and Physics, 2013,138:803 [4] Shuqin YANG, Shumin HAN, Jianzheng SONG, Yuan LI.
All alloys showed almost the same diffraction peaks, which indicated these alloys had the same structure.
As can in Fig.1(a), all alloys had the hexagonal CaCu5 type structure as the main crystal structure.
Generally, there is a single CaCu5 type structure in AB5 alloy, since Mg cannot be completely solid-soluted in CaCu5 type structure, part of Mg as a metastable form existed in CaCu5 type structure, and part of Mg combining with other elements (mainly Al, Mn) separated out.
Materials Chemistry and Physics, 2013,138:803 [4] Shuqin YANG, Shumin HAN, Jianzheng SONG, Yuan LI.
Online since: September 2011
Authors: Jin Qiang Liu, Yong Qiang Li, Ting Ting Liu, Ling Jie Meng
The principle of experimental device structure shown in Fig. 1.
Fig. 1 The principle structure of experimental device Fig. 2 Discharge plasma photo Steps of Plasma Treated Fabrics.
At 1602 cm-1 the absorption due to NH bending vibration, showes that the fabric structure contains amino groups.
Acknowledgments This research was funded by Zhejiang Provincial Top Academic Discipline of Applied Chemistry and Eco-Dyeing & Finishing Engineering (No.ZYG2010017) and Zhejiang Provincial Key Innovation Team (No.2010R50038).
Fig. 1 The principle structure of experimental device Fig. 2 Discharge plasma photo Steps of Plasma Treated Fabrics.
At 1602 cm-1 the absorption due to NH bending vibration, showes that the fabric structure contains amino groups.
Acknowledgments This research was funded by Zhejiang Provincial Top Academic Discipline of Applied Chemistry and Eco-Dyeing & Finishing Engineering (No.ZYG2010017) and Zhejiang Provincial Key Innovation Team (No.2010R50038).
Online since: June 2014
Authors: Yun Long Zhang, Cheng Hai Li, Xing Yi Li
While hydroxyapatite (HA) had similar chemical and crystallographic structures to bone, which was attractive with its bioactivity which can form a chemical bond with osseous tissue[1-4].
The possible reasons were as follows, the calcium zirconate reaction products can be formed during high temperature sintering, well the local network structure can be strengthened after the introducing of ZrO2.
When ZrO2 content was relatively low, the volume change was not enough to destroy the main network, so it would strengthen the network structure.
Calcium phosphates as substitution of bonetissues, Progress in Solid State Chemistry 2004 (32):1–31
The possible reasons were as follows, the calcium zirconate reaction products can be formed during high temperature sintering, well the local network structure can be strengthened after the introducing of ZrO2.
When ZrO2 content was relatively low, the volume change was not enough to destroy the main network, so it would strengthen the network structure.
Calcium phosphates as substitution of bonetissues, Progress in Solid State Chemistry 2004 (32):1–31
Online since: December 2011
Authors: Yun Tao Li, Xu Ma, Guang Da Liu, Wen Jun Zhang, Li Jun Yang
m
(a) (b)
Fig.3 Microstructure of base metal (a)(b)
20μm
(a) (b)
Fig.4 Microstructure of weld line (a)(b) in TWB(a) (b)
(a) (b)
Fig.5 Microstructure of HAZ (a)(b) in TWB(a) (b)
Figure 2 shows the structure of the welded joint, columnar crystal in the weld is perpendicular to the interface of molted pool metal.
Figure 4 shows that the structure of weld is martensite and flaky pearlite.
Fig. 10(a) and(b)clearly show large, deep dimples and cleavages. 4 Conclusions (1)From the structure of tailor TIG welded-blanks, it has been found that the microstructure of weld region is ferrites and pearlites, and the microstructure of HAZ is block-like pearlites and ferrites (2)From the stretch tests, it suggested that when the weld line parallels the tensile axis, σs ,σb and σs/σb is higher than that of the weld line perpendicular to the tensile axis.
Acknowledge: This work was supported by Ministry of industry and information Technology of the People’s Republic of China support project under Grant No. 2009ZX04014-063-03, Tianjin scientific and technical support project under Grant No. 08ZCKFGX02200, and Tianjin Key Subject for Materials Physics and Chemistry.
Figure 4 shows that the structure of weld is martensite and flaky pearlite.
Fig. 10(a) and(b)clearly show large, deep dimples and cleavages. 4 Conclusions (1)From the structure of tailor TIG welded-blanks, it has been found that the microstructure of weld region is ferrites and pearlites, and the microstructure of HAZ is block-like pearlites and ferrites (2)From the stretch tests, it suggested that when the weld line parallels the tensile axis, σs ,σb and σs/σb is higher than that of the weld line perpendicular to the tensile axis.
Acknowledge: This work was supported by Ministry of industry and information Technology of the People’s Republic of China support project under Grant No. 2009ZX04014-063-03, Tianjin scientific and technical support project under Grant No. 08ZCKFGX02200, and Tianjin Key Subject for Materials Physics and Chemistry.
Online since: February 2012
Authors: Tie Jun Chen
The element Hf also belongs to Group IVB having the similar electronic structure as Zr but with different atomic sizes [9].
The structure was examined by X-ray diffraction (XRD) and the thermal stability was investigated by differential scanning calorimetry (DSC) at a heating rate of 0.67 K /s.
Conclusions Base on the results of thermal analyses and X-ray diffraction for the Hf45.6Cu27.8Ni9.3Ti5Al12.4 bulk metallic glass, the glass forming ability and thermal properties can be summarized as follows: (1) According to X-ray diffraction data all the studied alloys with 3-7mm in diameter were found to have a glassy structure and the largest critical diameter of the samples prepared is 7mm
[9] Handbook of Chemistry and Physics, 62nd ed., DRD Press, Inc., Boca Raton, Florida
The structure was examined by X-ray diffraction (XRD) and the thermal stability was investigated by differential scanning calorimetry (DSC) at a heating rate of 0.67 K /s.
Conclusions Base on the results of thermal analyses and X-ray diffraction for the Hf45.6Cu27.8Ni9.3Ti5Al12.4 bulk metallic glass, the glass forming ability and thermal properties can be summarized as follows: (1) According to X-ray diffraction data all the studied alloys with 3-7mm in diameter were found to have a glassy structure and the largest critical diameter of the samples prepared is 7mm
[9] Handbook of Chemistry and Physics, 62nd ed., DRD Press, Inc., Boca Raton, Florida
Online since: March 2013
Authors: Abbasi A. Gandhi, Olga Korostynska, Alex Mason, Ahmed Al-Shamma'a, Syed A.M. Tofail
Disadvantages are the usually high degree of specialization and the simultaneous existence of several variables affecting the microwave measurement (temperature, density, moisture, structure, etc.) in material measurements [9].
Due to the large variety of possible structures, sensors can be designed for measurement of almost any kind of object.
McMonagle, "Structure and stability of hydroxyapatite: Density functional calculation and Rietveld analysis," Physical Review B, vol. 71, Mar 2005
Umegaki, "Acceleration and Deceleration of Bone-Like Crystal Growth on Ceramic Hydroxyapatite by Electric Poling," Chemistry of Materials, vol. 8, pp. 2697-2697, 1996
Due to the large variety of possible structures, sensors can be designed for measurement of almost any kind of object.
McMonagle, "Structure and stability of hydroxyapatite: Density functional calculation and Rietveld analysis," Physical Review B, vol. 71, Mar 2005
Umegaki, "Acceleration and Deceleration of Bone-Like Crystal Growth on Ceramic Hydroxyapatite by Electric Poling," Chemistry of Materials, vol. 8, pp. 2697-2697, 1996
Online since: January 2009
Authors: Zhao Ming Xie, Ya Fang Xiang, Yuan Chen, Fu Sheng Pan
Synergistic Effects of Al and Cr Addition on Microstructure
of Mg2Ni Hydrogen Storage Alloy
Zhaoming XIE 1, a, Fusheng PAN 2, b
, Yafang XIANG
1, c, Yuan CHEN
2, d
1
College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, China
2
College of Materials Science and Engineering, Chongqing University, Chongqing, China
a
xiezm@cqu.edu.cn, bfspan@cqu.edu.cn,
cxiangyafang2006@163.com, dchenyuan@cqu.edu.cn
Key words: Mg-based Hydrogen Storage Alloy, Element Substitute, Synergistic Effect
Abstracts.
Some Mg2Ni diffraction peaks were founded in Fig.1(a); Fig. 1(b) shows hat the intense diffraction peak of Mg2Ni and the weak diffraction peak of Al3Ni2 were existed after substituting Al for Mg in Mg2Ni, interestingly, a large amount of unidentified phase was found, which has a cubic structure differing from the hexagonal structure of Mg2Ni, Yuan and co-workers[7] have proved that the cubic structure is one kind of hydrogen adsorption phase, Mg3AlNi2; Fig.1(c) shows that non-hydrogen-adsorption phaseδ-[Cr, Ni] was formed in Mg2Ni0.8Cr0.2 by substituting Cr for Ni; Fig.1(d) shows Mg1.8Al0.2Ni0.8Cr0.2 hydrogen storage alloy was formed when Al and Cr were added into the Mg2Ni alloy to replace Mg and Ni, respectively, the XRD pattern indicated that considerable amount of hydrogen-adsorption phase Mg3AlNi2 was existed and a small amount of Al3Ni2 and δ-[Cr, Ni] were founded.
Some Mg2Ni diffraction peaks were founded in Fig.1(a); Fig. 1(b) shows hat the intense diffraction peak of Mg2Ni and the weak diffraction peak of Al3Ni2 were existed after substituting Al for Mg in Mg2Ni, interestingly, a large amount of unidentified phase was found, which has a cubic structure differing from the hexagonal structure of Mg2Ni, Yuan and co-workers[7] have proved that the cubic structure is one kind of hydrogen adsorption phase, Mg3AlNi2; Fig.1(c) shows that non-hydrogen-adsorption phaseδ-[Cr, Ni] was formed in Mg2Ni0.8Cr0.2 by substituting Cr for Ni; Fig.1(d) shows Mg1.8Al0.2Ni0.8Cr0.2 hydrogen storage alloy was formed when Al and Cr were added into the Mg2Ni alloy to replace Mg and Ni, respectively, the XRD pattern indicated that considerable amount of hydrogen-adsorption phase Mg3AlNi2 was existed and a small amount of Al3Ni2 and δ-[Cr, Ni] were founded.
Online since: March 2010
Authors: Ning Qiao, Jun Yu, Gang Wei
Figure 2(a) shows the
structure of Ni3P-TiO2 coatings, and Figure 2(b) shows the structure of TiO2 coatings without Ni3P
preparation.
The coatings mainly make up of Ni3P crystallite and TiO2(anatase phase) in structure as characterized by XRD.
Mei: Chemistry & Bioengineering, Vol. 23(2006), p.7 [4] H.
The coatings mainly make up of Ni3P crystallite and TiO2(anatase phase) in structure as characterized by XRD.
Mei: Chemistry & Bioengineering, Vol. 23(2006), p.7 [4] H.
Online since: August 2014
Authors: Nurul Hanim Shamsudin, Kamarul Aizat Abdul Khalid, Khairudin Mohamed
The crystalline structure of deposited ZnO nanowires and amorphous BSG substrate were characterized by X-Ray Diffractometer (Bruker, Cu Kα radiation).
The crystal structure of the ZnO nanowires and the amorphous nature of the BSG substrate were studied using XRD analysis.
The ZnO nanowires grown also shows the clear wurtzite structure.
Pauporté, J. of Photochemistry and Photobiology A: Chemistry, Vol. 111 (2010) p. 65-73 [4] X.
The crystal structure of the ZnO nanowires and the amorphous nature of the BSG substrate were studied using XRD analysis.
The ZnO nanowires grown also shows the clear wurtzite structure.
Pauporté, J. of Photochemistry and Photobiology A: Chemistry, Vol. 111 (2010) p. 65-73 [4] X.