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Online since: October 2020
Authors: Olga A. Moskalyuk, Vladimir E. Yudin, Ekaterina S. Tsobkallo
Dispersed materials of various structures are widely used as fillers for the creation of polymer composites with the required properties.
In the process of orientatin draw, leading to the hardening of the structure, its primary (usually spherulite) supramolecular structure is transformed into a fibrillar one, consisting of alternating crystalline (having a three-dimensional order) and amorphous (not having a three-dimensional order) regions [5].
Thus, carbon particles, to some extent loosening the polymer structure, create additional volume for a more «free» transition from non-oriented structures to the fibrillar one, contributing to the formation of a more perfect supramolecular structure, namely the formation of more ordered intrafibrillar amorphous regions, since the strength of amorphous-crystalline oriented polymer structures is determined mainly by their structure.
The observed effect may be associated with the formation of a more perfect fibrillar structure of the polymer matrix.
Myasnikova, The supramolecular structure of polymers, Chemistry, Leningrad Branch, 1977.
In the process of orientatin draw, leading to the hardening of the structure, its primary (usually spherulite) supramolecular structure is transformed into a fibrillar one, consisting of alternating crystalline (having a three-dimensional order) and amorphous (not having a three-dimensional order) regions [5].
Thus, carbon particles, to some extent loosening the polymer structure, create additional volume for a more «free» transition from non-oriented structures to the fibrillar one, contributing to the formation of a more perfect supramolecular structure, namely the formation of more ordered intrafibrillar amorphous regions, since the strength of amorphous-crystalline oriented polymer structures is determined mainly by their structure.
The observed effect may be associated with the formation of a more perfect fibrillar structure of the polymer matrix.
Myasnikova, The supramolecular structure of polymers, Chemistry, Leningrad Branch, 1977.
Online since: April 2016
Authors: Ya Jing Liu, Yu Qi, Jing Shao, Huai Xin Wei, Xin Zhao
Synthesis and characterization of Phenanthroimidazole derivatives as light-emitting and ambipolar materials
Ya-jing Liu1,2, Xin Zhao1,2,a ,Yu Qi1,2, Jing Shao1,2 and Huai-xin Wei1,2
1College of Chemistry, Biology and Material Engineering , Suzhou University of Science and Technology, Suzhou 215011,China
2Jiangsu Key Laboratory of Environmental Functional Materials, Jiangsu Suzhou 215009,China
a zhaoxinsz@126.com
Keywords:phenanthroimidazole; phenothiazine; bipolar; synthesis
Abstract.
The relationship between the chemical structure and the properties of these materials was evaluated.
Recently, bipolar OLEDs have aroused considerable interest because they can provide more balance in electron and hole fluxes, generate broad charge recombination zones, and simplify device structure[2].
Phenanthroimidazole is a π-conjugated and planar structure and the imidazole is an electron-deficient ring used as an acceptor unit.
The physical and photophysical properties of these compounds were investigated with the aim of understanding the structure-property relationships and developing novel bipolar materials in OLEDs.
The relationship between the chemical structure and the properties of these materials was evaluated.
Recently, bipolar OLEDs have aroused considerable interest because they can provide more balance in electron and hole fluxes, generate broad charge recombination zones, and simplify device structure[2].
Phenanthroimidazole is a π-conjugated and planar structure and the imidazole is an electron-deficient ring used as an acceptor unit.
The physical and photophysical properties of these compounds were investigated with the aim of understanding the structure-property relationships and developing novel bipolar materials in OLEDs.
Online since: January 2011
Authors: Qian Nie, Fang Gu
Preparation of LiCoO2 from Cathode Materials of Spent Lithium Ion Batteries
Gu Fang1,a Nie Qian1,b
1College of Food Engineering of Harbin University of Commerce Chemistry Center Harbin China 150076
agufangwell@126.com, bnieqian1963@yahoo.com.cn
Keywords: spent lithium-ion battery; carbon reduction; LiCoO2; recovery.
Processing of spent lithium batteries is relatively simple because the chemistry of their components is very different and there are relatively few elements present [3,4,5,6,7].
The crystal structures of regenerative LiCoO2 are characterized by X-ray diffraction (XRD, Rigaku D/MAX-RC) with Cu Kα radiation(λ = 1.5405 Å, 45.0 kV, 50.0 mA).
All the diffraction peaks were good agreement with standard card without any impurity, indicating that the 10mol% excess Li does not change the LiCoO2 structure.
Processing of spent lithium batteries is relatively simple because the chemistry of their components is very different and there are relatively few elements present [3,4,5,6,7].
The crystal structures of regenerative LiCoO2 are characterized by X-ray diffraction (XRD, Rigaku D/MAX-RC) with Cu Kα radiation(λ = 1.5405 Å, 45.0 kV, 50.0 mA).
All the diffraction peaks were good agreement with standard card without any impurity, indicating that the 10mol% excess Li does not change the LiCoO2 structure.
Online since: May 2012
Authors: Nicholas Mulei Musyoka, Leslie Felicia Petrik, Eric Hums
Synthesis of zeolite A, X and P from a South African coal fly ash
Nicholas Mulei Musyoka1,a, Leslie Petrik1,b and Eric Hums2
1,a,bEnvironmental and Nano Science Research Group, Department of Chemistry, University of the Western Cape, Private Bag X17 Bellville, 7535, South Africa.
2Consulting Environmental Catalysis, P.O.
Elements such as Na, Mg and K could act as counter ions in the zeolite structure although a higher quantity of Ca in not preferred since its presence is known to destabilizes the crystallization process [10].
Zeolite type A (LTA) is classified into three subgroups; K-LTA, Na-LTA and Ca-LTA depending on the type of exchangeable cations present in its structure [13].
Rao, Editor, Zeolite Chemistry and Catalysis, ACS, Amsterdam (1976), p. 80.
Elements such as Na, Mg and K could act as counter ions in the zeolite structure although a higher quantity of Ca in not preferred since its presence is known to destabilizes the crystallization process [10].
Zeolite type A (LTA) is classified into three subgroups; K-LTA, Na-LTA and Ca-LTA depending on the type of exchangeable cations present in its structure [13].
Rao, Editor, Zeolite Chemistry and Catalysis, ACS, Amsterdam (1976), p. 80.
Online since: September 2007
Authors: J. Radić-Perić
Radić-Perić
Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, P.O.Box 137,
11001 Belgrade, Serbia
len@ffh.bg.ac.yu
Keywords: B4C synthesis, Synthesis in plasma, Thermodynamics of B4C
Abstract.
The atomic structure of solid B4C consists of an arrangement of 12-atom icosahedra, and of linear 3-atom chains [14].
The most stable structure is that according to [14] with B11C icosahedron and CBC chain.
Pavlović: Proc. 10th International Symp. on Plasma Chemistry, Bochum, Germany Vol. 1 (1991) 1.4-20
The atomic structure of solid B4C consists of an arrangement of 12-atom icosahedra, and of linear 3-atom chains [14].
The most stable structure is that according to [14] with B11C icosahedron and CBC chain.
Pavlović: Proc. 10th International Symp. on Plasma Chemistry, Bochum, Germany Vol. 1 (1991) 1.4-20
Online since: February 2014
Authors: Ning Zhang Wang, Jing Liu, Shi Feng Liu, Shi Long Rong
Introduction
Strontium titanate (SrTiO3) is a kind of functional material with perovskite structure.
Then detect the powder constituent by X-ray diffraction (XRD), and observe the crystal structure, particle size and morphology by scanning electron microscopy (SEM).
Peter:Chemistry of Materials,Vol.20(2008), p.5628
[8] S.Q.Hu and S.H.Li: Engineering Chemistry & Metallurgy, Vol.15(1994),No.4,p.316(in chinese)
Then detect the powder constituent by X-ray diffraction (XRD), and observe the crystal structure, particle size and morphology by scanning electron microscopy (SEM).
Peter:Chemistry of Materials,Vol.20(2008), p.5628
[8] S.Q.Hu and S.H.Li: Engineering Chemistry & Metallurgy, Vol.15(1994),No.4,p.316(in chinese)
Online since: August 2013
Authors: Guo Li He, Hong Hong Yi, Xiao Long Tang, Fen Rong Li, Yun Dong Li, Kai Li
Activated carbon has a large specific surface area and developed pore structure but at the same time it has many macroporous and a very low density, so unit volume of the adsorption capacity of it is relatively small.
Journal of Radioanalytical and Nuclear Chemistry,1998,235(1-2): 77-82
Journal of Physical Chemistry C. 2007, 111 (4):1560-1562
[24] Chen Shuixia,Jing Ying,et al: Studies on the Structure of Several Activated Carbon Fibers and their Xenon Adsorption Properties.
Journal of Radioanalytical and Nuclear Chemistry,1998,235(1-2): 77-82
Journal of Physical Chemistry C. 2007, 111 (4):1560-1562
[24] Chen Shuixia,Jing Ying,et al: Studies on the Structure of Several Activated Carbon Fibers and their Xenon Adsorption Properties.
Online since: September 2013
Authors: Xin Rong Wen, Chang Qing Tu
Indirect Determination of Methimazole in Pharmaceutical Sample by Discoloration Spectrophotometry using Fe(Ⅲ)-Tiron System
Changqing Tu1,a and Xinrong Wen1,b
1College of Chemistry and Environment,Jiaying University,Meizhou, Guangdong 514015,
P.
Introduction Methimazole(1-methyl-2-mercaptoimidazole,the molecular structure of methimazole is shown in Fig. 1 ) is a kind of antithyroid drugs.
structure of methimazole It has been found that methimazole may cause some side effects such as nephritis, liver injury,skin allergy or the decrease of white blood cells in the blood, etc.Consequently, it is of great importance and significance for life science to determinate the content of methimazole.Up till now, various different methods have been applied for the determination of methimazole, such as spectrophotometry,1-2 derivative spectrophotometry,3 fluorescence emission analysis,4 biomime- tic enzyme-linked immunosorbent assay (BELISA) method,5 voltammetry,6 polarography and voltammetry,7 HPLC,8 kinetic method,9 square wave voltammetry,10 electrochemical analysis,11flow-injection,12-13 RP-HPLC,14 HPLC-UV,15 LC,16 GC-MS,17 etc.
Brief Handbook of Analytical Chemistry;Beijing University Press :Beijing, 1981;p262.
Introduction Methimazole(1-methyl-2-mercaptoimidazole,the molecular structure of methimazole is shown in Fig. 1 ) is a kind of antithyroid drugs.
structure of methimazole It has been found that methimazole may cause some side effects such as nephritis, liver injury,skin allergy or the decrease of white blood cells in the blood, etc.Consequently, it is of great importance and significance for life science to determinate the content of methimazole.Up till now, various different methods have been applied for the determination of methimazole, such as spectrophotometry,1-2 derivative spectrophotometry,3 fluorescence emission analysis,4 biomime- tic enzyme-linked immunosorbent assay (BELISA) method,5 voltammetry,6 polarography and voltammetry,7 HPLC,8 kinetic method,9 square wave voltammetry,10 electrochemical analysis,11flow-injection,12-13 RP-HPLC,14 HPLC-UV,15 LC,16 GC-MS,17 etc.
Brief Handbook of Analytical Chemistry;Beijing University Press :Beijing, 1981;p262.
Influence of the Electrolyte Composition on the Corrosion Behavior of Anodized AZ31B Magnesium Alloy
Online since: October 2020
Authors: Renato Altobelli Antunes, Leandro Antonio de Oliveira
The anodized coating fabricated using the 0.5 M Na2SiO3 electrolyte (Fig. 1d) presented a defective and non-uniform structure, however it covered the whole substrate.
The film formed in silicate/hydroxide mixture solution (Fig. 1e) exhibited a branched-like structure with the highest roughness surface overall.
Han: Materials Chemistry and Physics Vol. 107 (2008), p. 356
Okido: Bulletin Korean Chemistry Society Vol. 24 (2003), p. 975.
The film formed in silicate/hydroxide mixture solution (Fig. 1e) exhibited a branched-like structure with the highest roughness surface overall.
Han: Materials Chemistry and Physics Vol. 107 (2008), p. 356
Okido: Bulletin Korean Chemistry Society Vol. 24 (2003), p. 975.
Online since: March 2016
Authors: Si Yuan Long, Feng Hong Cao, Yun Gui Chen
Table 1 Chemistry composition of alloy
Alloy
Chemistry composition of alloy
Zn
Mn
Fe
Si
Ni
Cu
Zr
Mg
ZK80
8.26
0.0158
0.008
0.0044
0.0008
0.0015
0.7057
Bal.
Grain size non-uniform, eutectic product along the grain boundaries or dendrite boundary discontinuous distribution with the crystal with black second phase particles precipitated by SEM and EDS spectrum scanning analysis shows ZK80 Mg alloy lamellar structures and granular middle mainly MgZn and MgZn2, as show in Fig. 3, the base body is relatively clean and coarse grains, about 70μm.
As-cast ZK80 Mg alloy organization composed of matrix and the dendrite structure with MgZn and MgZn2 strengthening phase, it’s easy to form susceptible to cracking source under stress, and with the increase of stress, a small crack in quasi-cleavage within the management plane extensions to form a stepped manner rivers like pattern, typical of brittle fracture characteristics; under high strain conditions, the plastic deformation of the matrix phase and uncoordinated strengthen inter between dendrites resulting pores, pores and then long large and polymerized grow to form ductile fracture; in addition to there are crystalline particle morphology on the matrix with intergranular fracture mechanism characteristic[9].
Grain size non-uniform, eutectic product along the grain boundaries or dendrite boundary discontinuous distribution with the crystal with black second phase particles precipitated by SEM and EDS spectrum scanning analysis shows ZK80 Mg alloy lamellar structures and granular middle mainly MgZn and MgZn2, as show in Fig. 3, the base body is relatively clean and coarse grains, about 70μm.
As-cast ZK80 Mg alloy organization composed of matrix and the dendrite structure with MgZn and MgZn2 strengthening phase, it’s easy to form susceptible to cracking source under stress, and with the increase of stress, a small crack in quasi-cleavage within the management plane extensions to form a stepped manner rivers like pattern, typical of brittle fracture characteristics; under high strain conditions, the plastic deformation of the matrix phase and uncoordinated strengthen inter between dendrites resulting pores, pores and then long large and polymerized grow to form ductile fracture; in addition to there are crystalline particle morphology on the matrix with intergranular fracture mechanism characteristic[9].