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Online since: December 2012
Authors: H. Moayedi, S. Kazemian, A.H. Vakili
The characterization capabilities of EDX are due in large part to the fundamental principle that each element has a unique atomic structure allowing X-rays that are properties of an element's atomic structure to be identified uniquely from one another.
2.1.
The SEM results proved that by increasing the inorganic materials in the treated peat, the density of the confection increased with a corresponding decrease in the porosity (e.g. decreasing the micro and macro structure).
[7] Yu, T.R., Chemistry of Variable Charge Soils1997, London: Oxford University Press
The SEM results proved that by increasing the inorganic materials in the treated peat, the density of the confection increased with a corresponding decrease in the porosity (e.g. decreasing the micro and macro structure).
[7] Yu, T.R., Chemistry of Variable Charge Soils1997, London: Oxford University Press
Online since: September 2021
Authors: Isabele Maria Coman
This process also depends on the polymers structure but roughly it can be said that it mainly occurs due to breakage of polymer molecules.
As soon as they are in the environment, polymers are exposed to a variety of chemical and mechanical processes that cause a change in their structure, and the disintegration of polymers into smaller and smaller fragments begins.
Because all polymers have in their structure chemicals with low affinity to water, they have high molecular weight and hydrophobicity.
References [1] Conflicts in Chemistry: The Case of Plastics,Science History Institute, https://www.sciencehistory.org/the-history-and-future-of-plastics (2020)
As soon as they are in the environment, polymers are exposed to a variety of chemical and mechanical processes that cause a change in their structure, and the disintegration of polymers into smaller and smaller fragments begins.
Because all polymers have in their structure chemicals with low affinity to water, they have high molecular weight and hydrophobicity.
References [1] Conflicts in Chemistry: The Case of Plastics,Science History Institute, https://www.sciencehistory.org/the-history-and-future-of-plastics (2020)
Online since: April 2016
Authors: Magdalena Leśniak, Maciej Sitarz, Elżbieta Długoń, Wiktor Niemiec, Marzena Szymańska, Piotr Jeleń
Investigation on bioactivity of zirconium-calcium coatings on titanium surface obtained by sol-gel and electrophoretic deposition (EPD) methods
DŁUGOŃ Elżbieta1, SZYMAŃSKA Marzena1, LEŚNIAK Magdalena1*, JELEŃ Piotr1, NIEMIEC Wiktor1, SITARZ Maciej1
1 AGH University of Science and Technology, Faculty of Materials Science and Ceramics,
Department of Silicate Chemistry and Macromolecular Compounds
Al.
The crystal structure of the ceramic coatings on a metal surface was examined using Raman spectroscopy.
In 2002 Uchida continued research related to activity of bio-zirconium coatings obtained by the sol-gel method and he took up evaluation based on the ability of forming a layer of apatite on the surface of the heat treatment temperature and thus on the crystal structure of ZrO2.
The author has shown that the zirconia coatings, both in the tetragonal and the monoclinic structure have a much greater capacity for the formation of apatite in SBF as compared to the amorphous coatings [16].
The crystal structure of the ceramic coatings on a metal surface was examined using Raman spectroscopy.
In 2002 Uchida continued research related to activity of bio-zirconium coatings obtained by the sol-gel method and he took up evaluation based on the ability of forming a layer of apatite on the surface of the heat treatment temperature and thus on the crystal structure of ZrO2.
The author has shown that the zirconia coatings, both in the tetragonal and the monoclinic structure have a much greater capacity for the formation of apatite in SBF as compared to the amorphous coatings [16].
Online since: December 2013
Authors: Xian Ming Liu, De Guang Du, Xue Yi Yang
Structural and physical properties of antibacterial Ag-doped magnetic microspheres
Xianming Liu1, a , Xueyi Yang2, b and Deguang Du3 , c
1 College of Chemistry & Chemical Engineering, Luoyang Normal University, Henan Luoyang 471022, China
2 Department of Life Sciece, Luoyang Normal University, Henan Luoyang 471022, China
3 Henan Huier Nano Technology Co.
The structure, morphology and magnetic properties of the obtained samples were systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) vibrating sample magnetometer (VSM).
Crystalline structures of the products were analyzed using PXRD.
Besides the characteristic diffraction peaks of γ-Fe2O3 reflections, the diffraction at 38.06, 44.28, 64.38, and 77.4° 2θ shown in Figure 1b can be indexed to (111), (200), (220), and (311) planes of silver with the face-centered cubic (fcc) structure (space group: Fm3m), respectively (JCPDS card, No. 04-0783).
The structure, morphology and magnetic properties of the obtained samples were systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) vibrating sample magnetometer (VSM).
Crystalline structures of the products were analyzed using PXRD.
Besides the characteristic diffraction peaks of γ-Fe2O3 reflections, the diffraction at 38.06, 44.28, 64.38, and 77.4° 2θ shown in Figure 1b can be indexed to (111), (200), (220), and (311) planes of silver with the face-centered cubic (fcc) structure (space group: Fm3m), respectively (JCPDS card, No. 04-0783).
Online since: March 2014
Authors: Vitalijs Lakevičs, Valentīna Stepanova, Ieva Skuja, Inga Dušenkova, Augusts Ruplis
The acid treatment leads to severe mineral crystal structure alteration which is shown characteristic peaks lowering on the patterns, indicating a decrease in the regularity of the mineral structure.
The increase of the BET surface area under acid treatment may be caused by production of finely dispersed silicon oxides from destruction of mineral structures, removal of amorphous Al or silica components plugging surface pores.
Tyumina, Colloid chemistry of Latvian clays.
The increase of the BET surface area under acid treatment may be caused by production of finely dispersed silicon oxides from destruction of mineral structures, removal of amorphous Al or silica components plugging surface pores.
Tyumina, Colloid chemistry of Latvian clays.
Initial Attachment of Osteoblast-Like Cells on Functionalized Surfaces Coated with Calcium Phosphate
Online since: May 2006
Authors: Paul Ducheyne, I.M. Shapiro, R.J. Composto, George K. Toworfe, Christopher S. Adams
The self assembled monolayer (SAM) technology can be used to create highly controlled
surface chemistries, specifically surfaces with hydroxyl, carboxyl and amine-terminated groups.
The objectives of this study were to: synthesize materials with enhanced biological structures and functions for use in bone tissue repair therapies; explore the effect of Ca-P precipitates on SAMsgrafted substrates as a potential for bone tissue repair; develop an interfacially adherent and physiologically stable calcium phosphate coatings on an implant, and show these coatings produce a greater stimulatory effect in bone function.
The structure and composition of Ca-P precipitates formed on the -NH2, COOH, and -OH terminated surfaces, were determined by: Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), Energy dispersive X-ray analysis (/EDX) and Rutherford backscattering spectrometry (RBS, with 4He ++ at 3 MeV, Ω = 5msr, θLAB = 170 o ), while contact angle measurements and ellipsometry determined the wettability and thickness of Ca-P coatings.
The chemical structures of the self-assembled monolayers (SAMs) used in the surface functionalization process (SAM synthesis): GPTMS - glycidoxypropyl trimethoxysilane; TESPSA - triethoxysilylpropyl succinic anhydride; APTES - 3aminopropyltriethoxysilane.
The objectives of this study were to: synthesize materials with enhanced biological structures and functions for use in bone tissue repair therapies; explore the effect of Ca-P precipitates on SAMsgrafted substrates as a potential for bone tissue repair; develop an interfacially adherent and physiologically stable calcium phosphate coatings on an implant, and show these coatings produce a greater stimulatory effect in bone function.
The structure and composition of Ca-P precipitates formed on the -NH2, COOH, and -OH terminated surfaces, were determined by: Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), Energy dispersive X-ray analysis (/EDX) and Rutherford backscattering spectrometry (RBS, with 4He ++ at 3 MeV, Ω = 5msr, θLAB = 170 o ), while contact angle measurements and ellipsometry determined the wettability and thickness of Ca-P coatings.
The chemical structures of the self-assembled monolayers (SAMs) used in the surface functionalization process (SAM synthesis): GPTMS - glycidoxypropyl trimethoxysilane; TESPSA - triethoxysilylpropyl succinic anhydride; APTES - 3aminopropyltriethoxysilane.
Online since: October 2011
Authors: Yu Long Xu, Chuan Shou Sun, Guo Hua Liu
An efficient and recyclable imidazolium salts-functionalized mesoporous catalyst for microwave-promoted Knoevenagel
condensations in solid medium
Yulong Xu, Chuanshou Sun, Guohua Liu*
The Key Laboratory of Resource Chemistry of Ministry of Education, College of Life and Environmental Science, Shanghai Normal University, Shanghai 200234, P.
The 29Si MAS NMR spectrum showed clearly two groups of signals with four oxygen neighbors [Q-type species: Q4 (δ = -112 ppm) and Q3 (δ = -101 ppm)] originated from TEOS and one group of signals with three oxygen neighbors [T-type species: T3 (δ = -67 ppm)] derived from silylether groups.[12] The strong Q3 and Q4 signals suggested that 2 possessed mainly network structures of (HO)Si(OSi)3} and {Si(OSi)4}, while the relatively weak T3 signals indicated the formation of RSi(OSi)3} (R = N-methylimidazole molecules) as a part of wall in mesoporous structures.
Similar to pure SBA-15, the imidazolium salts-functionalized mesoporous catalyst 2 exhibited one similar intense d100 diffraction and two similar weak peaks indicative of d110 and d200 diffractions, implying that the ordered dimensional-hexagonal mesostructure (p6mm) observed in pure SBA-15 could be well preserved after the postgrafting.[14] In comparison with pure SBA-15, the decreases of peak intensities implied that the protection of silicon-hydroxyl groups and the postgrafting of organic silica resource in the SBA-15 might disturb the ordered mesoporous structure to a certain degree.
The 29Si MAS NMR spectrum showed clearly two groups of signals with four oxygen neighbors [Q-type species: Q4 (δ = -112 ppm) and Q3 (δ = -101 ppm)] originated from TEOS and one group of signals with three oxygen neighbors [T-type species: T3 (δ = -67 ppm)] derived from silylether groups.[12] The strong Q3 and Q4 signals suggested that 2 possessed mainly network structures of (HO)Si(OSi)3} and {Si(OSi)4}, while the relatively weak T3 signals indicated the formation of RSi(OSi)3} (R = N-methylimidazole molecules) as a part of wall in mesoporous structures.
Similar to pure SBA-15, the imidazolium salts-functionalized mesoporous catalyst 2 exhibited one similar intense d100 diffraction and two similar weak peaks indicative of d110 and d200 diffractions, implying that the ordered dimensional-hexagonal mesostructure (p6mm) observed in pure SBA-15 could be well preserved after the postgrafting.[14] In comparison with pure SBA-15, the decreases of peak intensities implied that the protection of silicon-hydroxyl groups and the postgrafting of organic silica resource in the SBA-15 might disturb the ordered mesoporous structure to a certain degree.
Online since: January 2016
Authors: Mohd Zainizan Sahdan, Nurulnadia Sarip, Sharul Ashikin Kamaruddin, Siti Nooraya Mohd Tawil, Farhanahani Mahmud
Unfortunately, as the coated substrates were being exposed to longer sonication times, it starts to modify the surface structure of the film by causing brutle surface distruction with inconsistent patterns as represented in Fig. 1 insets at low magnification imaging.
The diffraction spectra showed small peaks corresponding to the planes of hexagonal wurzite structure of ZnO with no characteristic peaks of impurities.
Surface structures of highly uniform quality ZnO nanorods with agglomerates and aggregates deficient, grown from acetate, which dominates over nitrate, could be formed using the proposed modified sol-gel route.
Yang: Inorganic Chemistry 45 (2006) 7535
The diffraction spectra showed small peaks corresponding to the planes of hexagonal wurzite structure of ZnO with no characteristic peaks of impurities.
Surface structures of highly uniform quality ZnO nanorods with agglomerates and aggregates deficient, grown from acetate, which dominates over nitrate, could be formed using the proposed modified sol-gel route.
Yang: Inorganic Chemistry 45 (2006) 7535
Online since: June 2025
Authors: Joao Pedro Almeida Lopes, Hebert Luis Rossetto
These challenges have led to the development of numerous waterproofing techniques aimed at extending the service life of concrete structures.
Surface treatments include coatings and sealants applied to the exterior of concrete structures, while integral systems involve adding waterproofing agents directly into the concrete mix.
This layer prevents water from being drawn into the concrete porous structure, thereby enhancing its durability.
Analytical and Bioanalytical Chemistry, v. 409, p. 5171–5183, 2017
Surface treatments include coatings and sealants applied to the exterior of concrete structures, while integral systems involve adding waterproofing agents directly into the concrete mix.
This layer prevents water from being drawn into the concrete porous structure, thereby enhancing its durability.
Analytical and Bioanalytical Chemistry, v. 409, p. 5171–5183, 2017
Online since: July 2011
Authors: Ju Gong Zheng, Ting Yang
Recently, many efficient approaches to fabricate hierarchical and complex CuO nano/microstructures have been reported, such as sonochemical synthesis [4], solid-state reaction [5], wet-chemistry route [6], solid-state reaction in the presence of surfactant polyethylene glycol (PEG) [7], MOCVD template method[8], alkoxide-based preparation[9], Hydrothermal synthesis via ionic liquids[2], etc.
Which act not only as a functional solvents for reaction precursors, but also morphologic templates for stabilize the formed structures [11-13].
The FTIR spectra of CuO nano-structure are shown in Fig. 1(b).
The wide diffraction line maybe is the result of the incomplete sample crystal structure.
Which act not only as a functional solvents for reaction precursors, but also morphologic templates for stabilize the formed structures [11-13].
The FTIR spectra of CuO nano-structure are shown in Fig. 1(b).
The wide diffraction line maybe is the result of the incomplete sample crystal structure.