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Online since: November 2022
Authors: Szymon Smykała, Barbara Liszka, Agata Blacha-Grzechnik, Mirosława Pawlyta
Comparison of catalyst structures before (a, c) and after (b, d) durability test.
The structure of the carbon support in the commercial catalyst is heterogeneous.
Catalyst structure after 100 cycles of potential changes in the range of 0.6-1.5V.
Analytical Chemistry, 82, 6321-6328
Journal of Electroanalytical Chemistry, 662(2), 355-360
The structure of the carbon support in the commercial catalyst is heterogeneous.
Catalyst structure after 100 cycles of potential changes in the range of 0.6-1.5V.
Analytical Chemistry, 82, 6321-6328
Journal of Electroanalytical Chemistry, 662(2), 355-360
Online since: May 2006
Authors: Besim Ben-Nissan, R. Roest, Hala Zreiqat, D. Haynes, Y. Ramaswamy
., 2052, Australia
2
Department of Chemistry, Materials and Forensic Science, University of Technology,
Sydney, P.O.
Considerable efforts have been taken to modify the surface structure of the implant material and improve the biological performance.
However plasma sprayed hydroxyapatite coating layer is known to be inhomogeneous in structure and have low bonding strength due to high processing temperature [4].
Surface chemistry and topography of biomaterials influence the cellular activity.
Moreover, in this process the rutile structure of the original titanium oxide converts into an oxide film containing mixed rutile and anatase crystalline structures [10].
Considerable efforts have been taken to modify the surface structure of the implant material and improve the biological performance.
However plasma sprayed hydroxyapatite coating layer is known to be inhomogeneous in structure and have low bonding strength due to high processing temperature [4].
Surface chemistry and topography of biomaterials influence the cellular activity.
Moreover, in this process the rutile structure of the original titanium oxide converts into an oxide film containing mixed rutile and anatase crystalline structures [10].
Online since: July 2014
Authors: Hai Ning Cui, Rong Wang, Feng Xu, He Wang, Yong Jian Chen, Bernabé Marí, Miguel Mollar
In this paper, We will focus the structure of ZnO films, especially pentagonal flake structure, relation of morphologies and the surface of substrates.
SEM reveals an aggregation of flat pentagonal flake which looks like ZnO quasi-3D structures consisted of quasi-nanowalls.
In case of Fig.2 above similar micro structure,an aggregation of flat pentagonal flake was not found.
This could be deduced that ZnO doped Ga on surface of polymer-PEN did not form good conductive layer and suitable structure of ZnO.
Generally it is realized that micro structure of ZnO film is of more functional and PL may gives much information about relation of the structure.
SEM reveals an aggregation of flat pentagonal flake which looks like ZnO quasi-3D structures consisted of quasi-nanowalls.
In case of Fig.2 above similar micro structure,an aggregation of flat pentagonal flake was not found.
This could be deduced that ZnO doped Ga on surface of polymer-PEN did not form good conductive layer and suitable structure of ZnO.
Generally it is realized that micro structure of ZnO film is of more functional and PL may gives much information about relation of the structure.
Online since: March 2011
Authors: Stephen E. Saddow, Francesco La Via, Andrea Canino, Nicolò Piluso, Andrea Severino, Ruggero Anzalone, Massimo Camarda, Christopher Locke, Giuseppe D'Arrigo, Antonino La Magna
Finite elements simulations of the micro-machined structures have also been carried out in order to evaluate, in detail, the stress field inside the structures and to test the analytical model used.
The system used for the plasma etching was an ICP plasma system with SF6/O2 chemistry.
To reach the complete suspension of the structure we used a 20% KOH solution at 60°C for 60 min to etch selectively the Si substrate under the SiC structures.
Result and Discussion In order to utilize efficiently the micro-rotating structure to measure residual stresses in thin films, the micro-structure needs to be optimally designed.
After that, a variety of optimized micro-rotating structures were designed.
The system used for the plasma etching was an ICP plasma system with SF6/O2 chemistry.
To reach the complete suspension of the structure we used a 20% KOH solution at 60°C for 60 min to etch selectively the Si substrate under the SiC structures.
Result and Discussion In order to utilize efficiently the micro-rotating structure to measure residual stresses in thin films, the micro-structure needs to be optimally designed.
After that, a variety of optimized micro-rotating structures were designed.
Online since: January 2011
Authors: Ming Duo Yang, Hong Wei Zhang, Xiang Fu Fan
The global food structure adjustment is toward the direction of fiber food, and there are more than 600 kinds of products, including more than 400 new kinds produced in recent years.
Extrusion technology does not cause the deep degradation or destruction of dietary fiber polymer structure, but under the strong forces in the extruder, part insoluble araboxylan hemicellulose and insoluble pectin compound will melt or part connection keys break, and transform to water-soluble polymer [8].
[6] Aoe S and Nakaoka M:Availability of dietary fiber in extruded wheat bran and apparent digestibility in rats.Cereal Chemistry(1989)
-M,KLOPFENSTEIN C F and PONTE J G:Effects of twin-screw extrusion on the physical properties of dietary fiber and other components of whole wheat and wheat bran and on the baking quality of the wheat bran.Cereal chemistry.
[13] Maria Lima Gardelotti,Deise Ap.Pinatti Marsiglia and Elizabeth A.F.S.Torres.Determination and validation of dietary fiber in food by enzymatic gravimetric method.Food Chemistry. 83(2003),p.469-473
Extrusion technology does not cause the deep degradation or destruction of dietary fiber polymer structure, but under the strong forces in the extruder, part insoluble araboxylan hemicellulose and insoluble pectin compound will melt or part connection keys break, and transform to water-soluble polymer [8].
[6] Aoe S and Nakaoka M:Availability of dietary fiber in extruded wheat bran and apparent digestibility in rats.Cereal Chemistry(1989)
-M,KLOPFENSTEIN C F and PONTE J G:Effects of twin-screw extrusion on the physical properties of dietary fiber and other components of whole wheat and wheat bran and on the baking quality of the wheat bran.Cereal chemistry.
[13] Maria Lima Gardelotti,Deise Ap.Pinatti Marsiglia and Elizabeth A.F.S.Torres.Determination and validation of dietary fiber in food by enzymatic gravimetric method.Food Chemistry. 83(2003),p.469-473
Online since: June 2015
Authors: Nurshaira Haifa Suhaimi, Abd Rahim Yacob, Mohd Khairul Asyraf Amat Mustajab
Rahim Yacob1, a,Mohd Khairul Asyraf Amat Mustajab1,b
and Nurshaira Haifa Suhaimi1,c
1Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor Darul Ta’zim, Malaysia
amanrahim@kimia.fs.utm.my, bkrulchubby84@yahoo.com, cshafaa.hairaa@gmail.com
Keywords: ESR, potassium doped Mo2C, UV irradiation
Abstract.The presence of potassium in molybdenum carbide morphology has been reported to increase the selectivity and reactivity of its catalytic properties.
Therefore, based on their structure, this electron may have a chance to interact with a vacant orbital, either 4d orbital from Mo or 2p orbital from C.
[2] S.T.Oyama, Chemistry of Transition Metal Carbides and Nitrides.
Journal of Physical Chemistry C, 112(2008) 2607-2612
Yacob, The ESR spectrum and structure of the mixed alkali metal cluster Na2K5 prepared using a rotating cryostat.
Therefore, based on their structure, this electron may have a chance to interact with a vacant orbital, either 4d orbital from Mo or 2p orbital from C.
[2] S.T.Oyama, Chemistry of Transition Metal Carbides and Nitrides.
Journal of Physical Chemistry C, 112(2008) 2607-2612
Yacob, The ESR spectrum and structure of the mixed alkali metal cluster Na2K5 prepared using a rotating cryostat.
Online since: October 2017
Authors: Radchada Buntem, Jutamas Rueangyodjantana
Studies on the Deterioration of Ancient Thai Manuscripts
Jutamas Rueangyodjantana1,a* and Radchada Buntem2,b*
1Graduate Program in Conservation of Fine Art, Graduate School, Silpakorn University,
Bangkok 10170, Thailand
2Department of Chemistry, Faculty of Science, Silpakorn University,
Nakhon Pathom 73000, Thailand
ajutamas.joom@gmail.com, bradchadab@yahoo.com
Keywords: Thai manuscript, Khoi paper, cellulose deterioration
Abstract.
Acknowledgements Many thanks to Phra Kru Siri Kaweewat, a deputy provost of Rachathiwat Ratchaworawihan temple for giving a kind permission to the ancient manuscript research, Graduate School, Silpakorn University for finantial support of JR and Depatment of Chemistry, Science Faculty, Silpakorn University for scientific instruments.
Kokol, The effect of the cellulose-binding domain from Clostridium cellulovorans on the supramolecular structure of cellulose fibers, Carbohydr.
Shiraishi, Wood and Cellulosic Chemistry, in: F.
Horii, Structure of Cellulose: Recent Developments in Its Characterization, 2nd ed.Marcel Dekker, New York 2001, pp. 83–108
Acknowledgements Many thanks to Phra Kru Siri Kaweewat, a deputy provost of Rachathiwat Ratchaworawihan temple for giving a kind permission to the ancient manuscript research, Graduate School, Silpakorn University for finantial support of JR and Depatment of Chemistry, Science Faculty, Silpakorn University for scientific instruments.
Kokol, The effect of the cellulose-binding domain from Clostridium cellulovorans on the supramolecular structure of cellulose fibers, Carbohydr.
Shiraishi, Wood and Cellulosic Chemistry, in: F.
Horii, Structure of Cellulose: Recent Developments in Its Characterization, 2nd ed.Marcel Dekker, New York 2001, pp. 83–108
Online since: September 2013
Authors: Wei Xiong, Jin Bo Wang, De Rong Liu, Bin Xu, Jian Feng
Production of 1,3-Propanediol by Catalytic Hydrogenolysis of Glycerol
Jian Feng1, a, Bin Xu2, b, Derong Liu1, Wei Xiong1 and Jinbo Wang1
1College of Chemistry and Chemical Engineering, Chongqing University of Science & Technology Chongqing 401331, PR China
2Key Laboratory of Green Catalysis of Sichuan Institutes of Higher Education, School of Chemistry and Pharmaceutical Engineering, Sichuan University of Science & Engineering
Zigong, Sichuan 643000, PR China
afengjianscu@yahoo.com, bjwdxb@163.com
Keywords: 1,3-Propanediol, Glycerol, Hydrogenolysis, Heterogeneous catalysis
Abstract.
And more importantly, using glycerol as feedstock is environment friendly and sustainable, which fulfils the requirements of “green chemistry”.
In fact, good selectivity to the desired products is still difficult to be controlled due to a lack of deep understanding of the relationship between the catalyst structure and its performance.
Future studies about the catalytic hydrogenolysis of glycerol to 1,3-PDO may focus on catalyst preparation, structure characterization and mechanism elucidation.
And more importantly, using glycerol as feedstock is environment friendly and sustainable, which fulfils the requirements of “green chemistry”.
In fact, good selectivity to the desired products is still difficult to be controlled due to a lack of deep understanding of the relationship between the catalyst structure and its performance.
Future studies about the catalytic hydrogenolysis of glycerol to 1,3-PDO may focus on catalyst preparation, structure characterization and mechanism elucidation.
Online since: October 2006
Authors: Kenneth P. Roberts, Saibal Mitra, Karthikk Sridharan
Roberts
2,b and Saibal Mitra
3,c,*
1Department of Chemical Engineering,
University of Tulsa, Tulsa, OK 74104, USA.
2Department of Chemistry and Biochemistry,
University of Tulsa, Tulsa, OK 74104, USA.
3Department of Physics and Engineering Physics, University of Tulsa, Tulsa, OK 74104,
USA.
The deposition conditions for tungsten oxide Filament Substrate Chemical Current (A) Temperature (o C) Structure 1 Tungsten coil 85 Hydrogen: 3 750 850 14 dark blue W18O49 nanorod 14 turns & 4 bubbler: yes strands 2 Tungsten coil 85 Methane: 3 790 900 3 blue black W18O49 nanorod 14 turns & 4 bubbler: yes strands 3 Tungsten coil 85 Oxygen: 60 780 950 8 ink blue W18O49 nanorod 14 turns & 4 bubbler: yes strands 4 Tungsten coil 85 Oxygen: 60 810 400 12 pale yellow m-WO3 rhombic 14 turns & 4 bubbler: No spheroids strands 5 Tungsten wires 70 Hydrogen: 3 550 780 4 dark blue W18O49 nanorod 0.04' dia bubbler: yes 3 wires 6 Tungsten wires 70 Oxygen: 60 580 400 5 pale yellow m-WO3 rhombic 0.04' dia bubbler: no spheroids 3 wires Sample No Filament/Source Pressure (torr) Gas Flow (SCCM) Time (min) Color of Deposit Structure indices of (010) and (020), respectively [15].
M.Boulova, and G.Lucazeau, Journal of Solid State Chemistry 167, 425 (2002). 25.
J.O.Hougen, R.R.Reeves, and G.G.Mannella, Industrial and Engineering Chemistry 48, 2 (1956). 27.
The deposition conditions for tungsten oxide Filament Substrate Chemical Current (A) Temperature (o C) Structure 1 Tungsten coil 85 Hydrogen: 3 750 850 14 dark blue W18O49 nanorod 14 turns & 4 bubbler: yes strands 2 Tungsten coil 85 Methane: 3 790 900 3 blue black W18O49 nanorod 14 turns & 4 bubbler: yes strands 3 Tungsten coil 85 Oxygen: 60 780 950 8 ink blue W18O49 nanorod 14 turns & 4 bubbler: yes strands 4 Tungsten coil 85 Oxygen: 60 810 400 12 pale yellow m-WO3 rhombic 14 turns & 4 bubbler: No spheroids strands 5 Tungsten wires 70 Hydrogen: 3 550 780 4 dark blue W18O49 nanorod 0.04' dia bubbler: yes 3 wires 6 Tungsten wires 70 Oxygen: 60 580 400 5 pale yellow m-WO3 rhombic 0.04' dia bubbler: no spheroids 3 wires Sample No Filament/Source Pressure (torr) Gas Flow (SCCM) Time (min) Color of Deposit Structure indices of (010) and (020), respectively [15].
M.Boulova, and G.Lucazeau, Journal of Solid State Chemistry 167, 425 (2002). 25.
J.O.Hougen, R.R.Reeves, and G.G.Mannella, Industrial and Engineering Chemistry 48, 2 (1956). 27.
Online since: August 2014
Authors: Siti Najila Mohd Janib, Martha K. Pastuszka, ZiBo Li, ShuangLong Liu, Radu O. Minea, Steve D. Swenson, Frank S. Markland, Peter S. Conti, J. Andrew Mackay
Below this length, the block copolymers (I18-S18, I24-S24, I36-S36) formed larger structures of unknown morphology.
Biopolymer engineering may provide new structures by self-assembly of various building blocks into bioresponsive micelles with a wide variety of properties.
Urry, Physical Chemistry of Biological Free Energy Transduction As Demonstrated by Elastic Protein-Based Polymers†, The Journal of Physical Chemistry B, 101 (1997) 11007-11028
MacKay, A quantitative recipe for engineering protein polymer nanoparticles, Polymer Chemistry, (2014)
Biopolymer engineering may provide new structures by self-assembly of various building blocks into bioresponsive micelles with a wide variety of properties.
Urry, Physical Chemistry of Biological Free Energy Transduction As Demonstrated by Elastic Protein-Based Polymers†, The Journal of Physical Chemistry B, 101 (1997) 11007-11028
MacKay, A quantitative recipe for engineering protein polymer nanoparticles, Polymer Chemistry, (2014)