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Online since: August 2011
Authors: Chun Xiao Xing, Chang Jiu Liu, Mei Rong Qi
High-Temperature Performance of Amorphous Nickel Hydroxide
Coated with La(OH)3
Changjiu Liu 1,2,a,*, Meirong Qi 1,Chunxiao Xing 1
1College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, China
2 Key Laboratory of New Processing Technology for Nonferrous Metals and Materials of Ministry of Education, Guilin University of Technology, Guilin 541004, China.
For amorphous material has a lot of unique structure and characteristics that is correlate to electrochemical activity of the electrode material [8,9], in this work, amorphous nickel hydroxide was coated with La(OH)3 by coprecipitation method.
Physical characterization of the prepared samples The phase structure of the prepared samples was determined by X-ray diffraction (XRD) analysis using X’ Pert Pro diffractometer, with a Cu Kα radiation source (λ=1.4581 Å, 40.0 kV, 100 mA).
This featureless appearance is typical of amorphous structure.
No diffraction peaks from La(OH)3 was observed in XRD pattern of La(OH)3 coated amorphous nickel hydroxide, which can be attributed to the very thin and badly crystallized structure of La(OH)3 coating.
For amorphous material has a lot of unique structure and characteristics that is correlate to electrochemical activity of the electrode material [8,9], in this work, amorphous nickel hydroxide was coated with La(OH)3 by coprecipitation method.
Physical characterization of the prepared samples The phase structure of the prepared samples was determined by X-ray diffraction (XRD) analysis using X’ Pert Pro diffractometer, with a Cu Kα radiation source (λ=1.4581 Å, 40.0 kV, 100 mA).
This featureless appearance is typical of amorphous structure.
No diffraction peaks from La(OH)3 was observed in XRD pattern of La(OH)3 coated amorphous nickel hydroxide, which can be attributed to the very thin and badly crystallized structure of La(OH)3 coating.
Online since: July 2012
Authors: Huai Liang Xu, Hong Bi, Yang Shen
Reduced Graphene Oxide Decorated with Fe3O4 Nanoparticles as High Performance Anode for Lithium Ion Batteries
Huai-liang Xua, Yang Shenb and Hong Bic
College of Chemistry and Chemical Engineering, Anhui University, Hefei 230039, P.R.
In order to improve cycle stability and rate performance of the anode materials, the one of strategies is to design and form a complex structure with particular conductive additives to adapt for large volume change and prevent active nanoparticles from aggregating, and thus improve the reversible capacity and rate capability of the electrodes.
Reduced graphene oxide(r-GO) is a two-dimensional (2D) nanomaterial possessing a good conductivity, high specific surface area, ultra-thin thickness and fair ductility, has been widely chosen as conducting matrixes for metal oxides to form complex structures to improve their cycle stability and rate performance [5-7].
All the characteristic peaks as labeled for both samples in Fig.2(a) are in good agreement with the crystalline structure of magnetite (JCPDS Card No. 75-0499) with cell constant a = 8.32Å.
The above results can be attributed to the flexible r-GO structure that is favorable for electrons and ions transportation, as well as the r-GO in composites effectively inhibiting the volume expansion and detachment of Fe3O4 nanoparticles during the charge-discharge cycles [12].
In order to improve cycle stability and rate performance of the anode materials, the one of strategies is to design and form a complex structure with particular conductive additives to adapt for large volume change and prevent active nanoparticles from aggregating, and thus improve the reversible capacity and rate capability of the electrodes.
Reduced graphene oxide(r-GO) is a two-dimensional (2D) nanomaterial possessing a good conductivity, high specific surface area, ultra-thin thickness and fair ductility, has been widely chosen as conducting matrixes for metal oxides to form complex structures to improve their cycle stability and rate performance [5-7].
All the characteristic peaks as labeled for both samples in Fig.2(a) are in good agreement with the crystalline structure of magnetite (JCPDS Card No. 75-0499) with cell constant a = 8.32Å.
The above results can be attributed to the flexible r-GO structure that is favorable for electrons and ions transportation, as well as the r-GO in composites effectively inhibiting the volume expansion and detachment of Fe3O4 nanoparticles during the charge-discharge cycles [12].
Online since: August 2013
Authors: Qian Wang, Wei Guang Li, Jiu Guang Geng
The radial structure SBS produced in China was used as asphalt modifying agents in the study.
At the same time, the segment structure of SBS could break, and this is the main degradation reasons of SBS in the aging process of modified asphalt binders.
Influence of aging on the evolution of structure, morphology and rheology of base and SBS modified bitumen, Constr Build Mater., 23 (2009) 1005–1010
Changes in asphalt chemistry and durability during oxidation and polymer modification, Petroleum Sci Technol, 19(9-10), 1229-1249
[8] Jiuguang Geng, Qing Chang, Jianan Yuan, Jingliang Dai, Study on SBS Modified Asphalt Crosslink Structure and Its Stabilization by GPC, Journal of Zhengzhou University(Engineering Science), 29(2008)13-16
At the same time, the segment structure of SBS could break, and this is the main degradation reasons of SBS in the aging process of modified asphalt binders.
Influence of aging on the evolution of structure, morphology and rheology of base and SBS modified bitumen, Constr Build Mater., 23 (2009) 1005–1010
Changes in asphalt chemistry and durability during oxidation and polymer modification, Petroleum Sci Technol, 19(9-10), 1229-1249
[8] Jiuguang Geng, Qing Chang, Jianan Yuan, Jingliang Dai, Study on SBS Modified Asphalt Crosslink Structure and Its Stabilization by GPC, Journal of Zhengzhou University(Engineering Science), 29(2008)13-16
Online since: April 2016
Authors: Farida V. Nazipova, Ruslan R. Safin, Štefan Barcík, Radis Reshidovich Ziatdinov, Aigul Ravilevna Shaikhutdinova, Elena A. Beliakova, Pavel A. Kainov
However some of the properties of wood negatively affect the structure process, strength and resistance of CBPB to moisture.
As a result of cavitations the cell structures are destructed which speeds up the transition of soluble process of substances into extractant due to their washing.
Ultrasound causes a number of specific effects – cavitations in fluids, leading to disruption of the diffusion layer and, as a consequence, to the rapid penetration of the fluid into the particle structure, to the extracting the soluble components and to quality mixing of the components of the medium.
Extraction with distilled water using ultrasound increases the speed of the process and the amount of extraction of "cement poisons" that can significantly improve the structure formation during solidification of cement. 2.
Ferreira, Adsorption of cations from a cement suspension onto lignocellulosic substrates and its influence on cement setting, Journal of Wood Chemistry and Technology. 25 (2005) 231–244
As a result of cavitations the cell structures are destructed which speeds up the transition of soluble process of substances into extractant due to their washing.
Ultrasound causes a number of specific effects – cavitations in fluids, leading to disruption of the diffusion layer and, as a consequence, to the rapid penetration of the fluid into the particle structure, to the extracting the soluble components and to quality mixing of the components of the medium.
Extraction with distilled water using ultrasound increases the speed of the process and the amount of extraction of "cement poisons" that can significantly improve the structure formation during solidification of cement. 2.
Ferreira, Adsorption of cations from a cement suspension onto lignocellulosic substrates and its influence on cement setting, Journal of Wood Chemistry and Technology. 25 (2005) 231–244
Online since: February 2016
Authors: Agnieszka Szczotok
Solidified single crystal Ni-based superalloys are highly heterogeneous dendritic structures (Figs. 1-3).
During solidification through the mushy zone, some of the solute elements prefer to remain in the liquid phase, while others preferentially diffuse to the solid phase, forming a chemical heterogeneity in the solidified structure with a significant fraction of the (γ+γ') eutectic in the interdendritic region (Figs. 1,2).
It is an example of a typical dendritic structure.
They result in homogenization of the dendritic structure (better in the case of the SSHT).
Tin, Nickel-based superalloys for advanced turbine engines: chemistry, microstructure and properties, J.
During solidification through the mushy zone, some of the solute elements prefer to remain in the liquid phase, while others preferentially diffuse to the solid phase, forming a chemical heterogeneity in the solidified structure with a significant fraction of the (γ+γ') eutectic in the interdendritic region (Figs. 1,2).
It is an example of a typical dendritic structure.
They result in homogenization of the dendritic structure (better in the case of the SSHT).
Tin, Nickel-based superalloys for advanced turbine engines: chemistry, microstructure and properties, J.
Online since: March 2007
Authors: Ao Guo, Yun Yi Fu, Lun Hui Guan, Zu Jin Shi, Zhen Nan Gu, Ru Huang, Xing Zhang
Department of Chemistry, Peking University , Beijing 100871, P.R.
Because of the hollow structure of single-walled carbon nanotubes, fullerene or endohedral matallofullerene can be inserted inside, forming a peapod-like structure [3-5] .
The structures of as-synthesized fullerene peapods were examined by high-resolution transmission electron microscopy (HRTEM, Hitachi, HR-9000).
Ring-shaped objects, with diameter close to 0.7nm, are attributed to individual fullerene molecules and they are aligned almost linearly along the tube axis, forming one-dimension chain-like structure.
Because of the hollow structure of single-walled carbon nanotubes, fullerene or endohedral matallofullerene can be inserted inside, forming a peapod-like structure [3-5] .
The structures of as-synthesized fullerene peapods were examined by high-resolution transmission electron microscopy (HRTEM, Hitachi, HR-9000).
Ring-shaped objects, with diameter close to 0.7nm, are attributed to individual fullerene molecules and they are aligned almost linearly along the tube axis, forming one-dimension chain-like structure.
Online since: October 2014
Authors: Ming Gao, Chun Feng Sun
Introduction
Nanometer is a unit of measurement, i.e. using the m unitto describe the size of a certain kind of material that is the in the size between 1-100 nanometer unit, the nanoparticles consists of a few atom group of molecule or atoms, the surface of the atoms are neither long procedure nor short-amorphous layer, and the core portion of the particle is a good crystal periodic atomic arrangement, but its structure is slightly different from the bulk sample, because of the special structure of the nanoparticles to the surface area and volume of the ratio of the sharp increases, causing its physical and chemical properties of the mutant to produce surface effects and volume effects[1-6].
Conclusion Experimental Results. 1) The surface treatment can melt and disperse nano CaCO3 in the substrate structure of polypropylene through an appropriate interface with the substrate binding form, which can produce well mechanical proformanced polypropylene/nano calcium carbonate. 2) The reinforcing effect of Nano-CaCO3 on the toughness of polypropylene is not obvious, but it helps to maintain the toughness of the original polypropylene. 3) PP/Nano CaCO3 composites have obvious brittle-ductile transition phenomenon, with the substrate toughness, brittle-ductile transition threshold amount required for nano-CaCO3 is smaller, the higher the toughening amplitude.
Nano CaCO3 is a kind of rigid particles themselves can not be deformed, but much higher than the modulus polypropylene substrate, after coupling surface treatment, surface nano-CaCO3 formation of lipophilic surface layer to the internal rigid particles together to form a " core - shell "structure.
References [1] Li Quan, Zeng Guang-bin, Xi full Chemistry
Conclusion Experimental Results. 1) The surface treatment can melt and disperse nano CaCO3 in the substrate structure of polypropylene through an appropriate interface with the substrate binding form, which can produce well mechanical proformanced polypropylene/nano calcium carbonate. 2) The reinforcing effect of Nano-CaCO3 on the toughness of polypropylene is not obvious, but it helps to maintain the toughness of the original polypropylene. 3) PP/Nano CaCO3 composites have obvious brittle-ductile transition phenomenon, with the substrate toughness, brittle-ductile transition threshold amount required for nano-CaCO3 is smaller, the higher the toughening amplitude.
Nano CaCO3 is a kind of rigid particles themselves can not be deformed, but much higher than the modulus polypropylene substrate, after coupling surface treatment, surface nano-CaCO3 formation of lipophilic surface layer to the internal rigid particles together to form a " core - shell "structure.
References [1] Li Quan, Zeng Guang-bin, Xi full Chemistry
Online since: May 2019
Authors: Kai Bo Pan, Jing An, Bi Zhen Yuan, Xiu Hua Huang, Bai Yang, Zhan Chen Cui, Xiao Dan Lv
China
2Zhuhai Laboratory of Supramolecular Materials, Jilin University, Zhuhai, 519041, PR China
3State Key Lab of Supramolecular Structure and Materials College of Chemistry, Jilin University, Changchun 130012, P.R.
The structure of the CPDs were investigated by Fourier transform infrared (FT-IR) spectra.
Fig. 1 The FTIR spectra of oPD, folic acid and CPDs, respectively a) b) Fig. 2 (a) TEM image m of CPDs; inset: HRTEM images of CPDs (b) TEM image of CPDs-Cu2+ The transmission electron microscopy (TEM) image (Fig. 2a) suggests that CPDs have a nearly spherical structure with uniform size nearby 10 nm.
Open Project of State Key Laboratory of Supramolecular Structure and Materials (Grant No. sklssm201814), Doctoral Promotion Program of Zhuhai College, Jilin University and Special Fund for Scientific and Technological Innovation of Guangdong University Students in 2018 (Special Fund for Climbing Plan, Grant No. pdjh2018b0623).
The structure of the CPDs were investigated by Fourier transform infrared (FT-IR) spectra.
Fig. 1 The FTIR spectra of oPD, folic acid and CPDs, respectively a) b) Fig. 2 (a) TEM image m of CPDs; inset: HRTEM images of CPDs (b) TEM image of CPDs-Cu2+ The transmission electron microscopy (TEM) image (Fig. 2a) suggests that CPDs have a nearly spherical structure with uniform size nearby 10 nm.
Open Project of State Key Laboratory of Supramolecular Structure and Materials (Grant No. sklssm201814), Doctoral Promotion Program of Zhuhai College, Jilin University and Special Fund for Scientific and Technological Innovation of Guangdong University Students in 2018 (Special Fund for Climbing Plan, Grant No. pdjh2018b0623).
Online since: March 2017
Authors: Tengku Shafazila Tengku Saharuddin, Alinda Samsuri, Fairous Salleh, Mohamed Wahab Mohamed Hisham, Rizafizah Othaman, Mohd Ambar Yarmo
Effect of Noble Metal Silver on the Reduction Behaviour of Molybdenum Oxide Using Carbon Monoxide
Alinda SAMSURI1,2,a, Fairous SALLEH1,b,
Tengku Shafazila TENGKU SAHARUDDIN1,c, Rizafizah OTHAMAN1,d, Mohammad Wahab MOHAMMAD HISHAM1,e and Mohd Ambar YARMO1,f
1School of Chemical Science & Food Technology, Faculty of Science and Technology,
Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, Malaysia
2Department of Chemistry, Centre for Defence Foundation Studies,
Universiti Pertahanan Nasional Malaysia, Kem Sungai Besi, 57000 Kuala Lumpur, Malaysia
aalindasamsuri@gmail, bfairoussalleh@gmail.com, ctengkushafazila@gmail.com, drizafizah@ukm.edu.my, ehisham5011@gmail.com and fambar@ukm.edu.my
Keywords: Molybdenum oxide, Silver, Reduction, Carbon monoxide
Abstract.
The crystal structures of the catalysts before and after reactions were determined by XRD's Bruker AXS D8 Advance type.
It shows that undoped MoO3 mainly exists as MoO3 in orthorhombic structure (JCPDS card no. 05-0508).
However, minimal change was observed on XRD patterns with respect to the display orthorhombic structure of silver molybdenum oxide, Ag2Mo2O7 (JCPDS card no. 75-1505) which proved that the impregnation of silver on the MoO3 was indeed successful.
Present of orthorhombic structure promoted high coverage of CO adsorption that indirectly improved reducibily of MoO3 [6].
The crystal structures of the catalysts before and after reactions were determined by XRD's Bruker AXS D8 Advance type.
It shows that undoped MoO3 mainly exists as MoO3 in orthorhombic structure (JCPDS card no. 05-0508).
However, minimal change was observed on XRD patterns with respect to the display orthorhombic structure of silver molybdenum oxide, Ag2Mo2O7 (JCPDS card no. 75-1505) which proved that the impregnation of silver on the MoO3 was indeed successful.
Present of orthorhombic structure promoted high coverage of CO adsorption that indirectly improved reducibily of MoO3 [6].
Online since: November 2016
Authors: Alexey A. Ogoltcov, Semen Sokolov, Alexander A. Vasilyev, Dmitry Sokolov
Since the time the first appearance introduced models [1,2], there has been a trend to develop more physically sound models for describing the complex processes of austenite microstructure evolution and transformation under hot rolling and accelerated cooling with formation of different structural components of structure such as polygonal ferrite, pearlite, bainite and martensite.
The benefits of like that models is higher possibilities of complex alloying effects determination in structure formation based on the thermodynamic and kinetic process parameters [3−5].
The program implements an integral mathematical model of the following interrelated processes of steel structure evolution: ‒ grain growth; ‒ dynamic recrystallization; ‒ static recrystallization providing for the effects of recovery and precipitation of carbonitrides of micro-alloying elements on the dislocations of deformed austenite.
The mathematical models of the above-given processes of structuring were published elsewhere [3,5].
Before optimization After optimization 3 7 18 36 24 10 2 0 0 380-400 400-420 420-440 440-460 460-480 480-500 500-520 520-540 540-560 Yield stress frequency distribution, % 0 0 5 16 26 24 14 6 9 380-400 400-420 420-440 440-460 460-480 480-500 500-520 520-540 540-560 Yield stress frequency distribution, % 0.08C; 0.8Mn; 0.04Nb; 0.015Ti 0.08C; 1.4Mn; 0.025Nb; 0.005Ti 93,7% 6,3% 0,0% 0,0% 0,0% 0,0% 0,0% polygonal ferrite perlite granular bainite lath bainite acicular ferrite martensite austenite 0,4% 0,0% 44,4% 18,4% 36,8% 0,0% 0,0% polygonal ferrite perlite granular bainite lath bainite acicular ferrite martensite austenite requirements requirements Fig. 7 Illustration of STAN 2000 program application for steel chemistry and microstructure optimization (strip 4x1280 mm).
The benefits of like that models is higher possibilities of complex alloying effects determination in structure formation based on the thermodynamic and kinetic process parameters [3−5].
The program implements an integral mathematical model of the following interrelated processes of steel structure evolution: ‒ grain growth; ‒ dynamic recrystallization; ‒ static recrystallization providing for the effects of recovery and precipitation of carbonitrides of micro-alloying elements on the dislocations of deformed austenite.
The mathematical models of the above-given processes of structuring were published elsewhere [3,5].
Before optimization After optimization 3 7 18 36 24 10 2 0 0 380-400 400-420 420-440 440-460 460-480 480-500 500-520 520-540 540-560 Yield stress frequency distribution, % 0 0 5 16 26 24 14 6 9 380-400 400-420 420-440 440-460 460-480 480-500 500-520 520-540 540-560 Yield stress frequency distribution, % 0.08C; 0.8Mn; 0.04Nb; 0.015Ti 0.08C; 1.4Mn; 0.025Nb; 0.005Ti 93,7% 6,3% 0,0% 0,0% 0,0% 0,0% 0,0% polygonal ferrite perlite granular bainite lath bainite acicular ferrite martensite austenite 0,4% 0,0% 44,4% 18,4% 36,8% 0,0% 0,0% polygonal ferrite perlite granular bainite lath bainite acicular ferrite martensite austenite requirements requirements Fig. 7 Illustration of STAN 2000 program application for steel chemistry and microstructure optimization (strip 4x1280 mm).