scholarly journals F-doping of nanostructured ZnO: a way to modify structural, electronic, and surface properties

2020 ◽  
Vol 22 (20) ◽  
pp. 11273-11285 ◽  
Author(s):  
Elisabeth Hannah Wolf ◽  
Marie-Mathilde Millet ◽  
Friedrich Seitz ◽  
Frenio A. Redeker ◽  
Wiebke Riedel ◽  
...  
Keyword(s):  
Electronic Properties ◽  
Surface Properties ◽  
Surface Acidity ◽  
Ft Ir

The structure, electronic properties, and surface acidity of polycrystalline ZnO are modified using F2(g). The amount of F incorporated influences the samples' properties, which were studied using, e.g., FT-IR, XPS, TEM, NMR, and microcalorimetry.

scholarly journals Characterization and Catalytic Behaviour of Co3(PO4)2–AlPO4 Catalysts

1998 ◽  
Vol 16 (4) ◽  
pp. 285-293 ◽  
Author(s):  
M.R. Mostafa ◽  
F.Sh. Ahmed
Keyword(s):  
Pore Radius ◽  
Surface Acidity ◽  
Total Pore Volume ◽  
Textural Properties ◽  
Acid Sites ◽  
Adsorption Of Nitrogen ◽  
Amorphous Structures ◽  
Ft Ir ◽  
Catalytic Behaviour ◽  
The Mean

Co3(PO4)2, AlPO4 and the binary system Co3(PO4)2-AlPO4 with different compositions were prepared by the coprecipitation method. The structural properties of these samples were determined using XRD, DTA and FT-IR techniques. The textural properties were determined from the adsorption of nitrogen at 77 K. The surface acidity was measured by a calorimetric titration method. The samples were tested as catalysts in the dehydration of ethanol and isopropanol using a pulse microcatalytic technique. The data obtained from XRD and FT-IR indicate the amorphous structures of the prepared catalysts. An increase in Co3(PO4)2 content led to a decrease in the surface area and in the total pore volume and an increase in the mean pore radius. The surface acidity of the catalyst depends on the chemical composition; the surface acidity increased with an increase in the AlPO4 content. The dehydration temperature and the distribution of acid sites are important parameters in determining the selectivity and activity of the catalyst.

A theoretical study of the geometries, and electronic and surface properties of sphere-like (SiB)2n (n = 6–27, 30) functional nanomaterials

2019 ◽  
Vol 21 (45) ◽  
pp. 25302-25310 ◽  
Author(s):  
Run-Ning Zhao ◽  
Zi-Chen Lu ◽  
Rui Chen ◽  
Ju-Guang Han
Keyword(s):  
Electronic Properties ◽  
Surface Properties ◽  
Theoretical Study ◽  
Functional Nanomaterials ◽  
Exchange Correlation

The geometries and electronic properties of (SiB)2n (n = 6–27, 30) clusters are systematically investigated based on the gradient corrected Perdew–Burke–Ernzerhof exchange–correlation functional.

Thermo-mechanical and surface properties of POSS reinforced structurally different diamine cured epoxy nanocomposites

RSC Advances ◽  
2014 ◽  
Vol 4 (85) ◽  
pp. 45433-45441 ◽  
Author(s):  
K. Sethuraman ◽  
P. Prabunathan ◽  
M. Alagar
Keyword(s):  
Bisphenol A ◽  
Surface Properties ◽  
Nmr Spectra ◽  
Epoxy Nanocomposites ◽  
H Nmr ◽  
Ft Ir ◽  
C Nmr

In the present study three structurally different diamines namely bisphenol-A based ether diamine, octane diol based ether diamine, and capron based diamine were synthesized and characterized using FT-IR, 1H-NMR and 13C-NMR spectra.

New polyurethane materials from renewable resources: synthesis and characterization

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Doina Macocinschi ◽  
Daniela Filip ◽  
Stelian Vlad
Keyword(s):  
Surface Properties ◽  
Renewable Resources ◽  
Tensile Tests ◽  
Cellulose Derivative ◽  
Alternative Methods ◽  
Synthesis And Characterization ◽  
Cellulose Derivatives ◽  
Domain Structures ◽  
Ft Ir ◽  
Mechanical Tensile

AbstractIn the present study new types of polyurethane-cellulose derivative biomaterials based on urethane prepolymers functionalized with hydroxypropylcellulose are presented. The aim of the present study is to obtain materials with better haemocompatibility, biocompatibility and amphiphilic microphase-separated domain structures. The outcome of remarkable chemical versatility characteristic to polyurethane materials combined with polymers derived from nature like cellulose derivatives resulting in bulk and surface properties is evidenced by means of different techniques like DSC, TGA, FT-IR, AFM and mechanical tensile tests. The influence of various factors on the developed morphologies and the microstructural changes is investigated. Both polyester and polyether macrodiols have been used to prepare these polyurethanes. The aim of this study is to find also alternative methods for improving biostability while maintaining the excellent biocompatibility and other properties.

Adhesion of Acidithiobacillus Caldus and Leptospirillum Ferriphilum on Pyrite and their Effect on Surface Properties of Sulfide Minerals

2009 ◽  
Vol 71-73 ◽  
pp. 449-452
Author(s):  
G. Gu ◽  
Li Jun Su ◽  
Guan Zhou Qiu ◽  
Y. Hu
Keyword(s):  
Surface Properties ◽  
Isoelectric Point ◽  
Sulfide Minerals ◽  
Ferrous Ion ◽  
Bacterial Cells ◽  
Leptospirillum Ferriphilum ◽  
Acidithiobacillus Caldus ◽  
Ft Ir ◽  
Bacterial Adsorption ◽  
Strong Ability

Acidithiobacillus caldus and Leptospirillum ferriphilum cells grown in different energy substances (ferrous ion, sulfur and pyrite) were used. The adhesion of A. caldus and L. ferriphilum cells on pyrite and their effect on pyrite surface properties were studied by adsorption, zeta-potential and FT-IR methods, and the corrosion images of pyrite interaction with bacteria were examined using atomic force microscopy. Research showed that pyrite isoelectric point (IEP) after interaction with bacterial cells shifted towards cells isoelectric point, and the shift degree in case of interaction with A. caldus was observed to be much more pronounced than for interaction with L. ferriphilum, which can be due to higher affinity of A. caldus towards pyrite. The FT-IR spectra of pyrite treated with bacterial cells revealed the presence of the cell functional groups signifying cells adsorption. Although the adsorption density of A. caldus on pyrite was higher than that of L. ferriphilum, L. ferriphilum with strong ability to oxidize ferrous ion showed better leaching efficiency than A. caldus with strong ability to oxidize sulfur for pyrite leaching. The results demonstrated that more important of indirect action (L. ferriphilum) than direct action (A. caldus) on pyrite.Introduction Bacterial adsorption to minerals is an initial step in bacterial leaching for metal recovery [1]. It has been reported that bacterial adhesion is dependent not only on the biochemical properties of the organism but also on the interfacial properties of the various interfaces existing in a bioleaching system[2].The bacteria-mineral interactions result in the changes of their surface properties. The elucidation of their alternate will be beneficial for bioleaching processes. Both Acidithiobacillus caldus and Leptospirillum ferriphilum are known for their ability to inhabit acidic environments and derive energy from oxidation of inorganic substances with natural occurrence in ore deposits and acid mine drainage and high affinity towards sulfide minerals [3-5]. In this work, the alterations of surface properties of pyrite after interaction with L. ferriphilum and A. caldus are studied, and the changes in surface properties caused by bacterial adsorption are discussed with reference to bioleaching behavior of pyrite.

Surface properties in an external electric field

1991 ◽  
Vol 334 (1635) ◽  
pp. 527-538 ◽  
Keyword(s):  
Electric Field ◽  
Work Function ◽  
Electronic Properties ◽  
External Electric Field ◽  
Surface Properties ◽  
Field Dependence ◽  
Effective Charge ◽  
Image Plane ◽  
Embedding Method ◽  
Surface Displacements

This paper reviews recent calculations on the effect of an external electric field on surface electronic properties, in particular using the embedding method for solving the Schrödinger equation at the surface. The shape of the screening charge and its field dependence are discussed, and the results are compared with experiments in which the image plane is determined. The force on the surface atoms in the field is given in terms of an effective charge, which also determines the work-function variation with surface displacements. This relationship can lead to a surface instability if the effective charge is big enough.

FT-IR study of the surface properties of K2O-TiO2

1986 ◽  
Vol 27 (1) ◽  
pp. 114-126 ◽  
Author(s):  
Guido Busca ◽  
Gianguido Ramis
Keyword(s):  
Surface Properties ◽  
Ft Ir ◽  
Ir Study

FT-IR characterization of the surface acidity of different titanium dioxide anatase preparations

1985 ◽  
Vol 14 ◽  
pp. 245-260 ◽  
Author(s):  
Guido Busca ◽  
Helene Saussey ◽  
Odette Saur ◽  
Jean Claude Lavalley ◽  
Vincenzo Lorenzelli
Keyword(s):  
Titanium Dioxide ◽  
Surface Acidity ◽  
Ft Ir

scholarly journals Surface Properties of Poly(Hydroxyurethane)s Based on Five-Membered Bis-Cyclic Carbonate of Diglycidyl Ether of Bisphenol A

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5184
Author(s):  
Mariusz Tryznowski ◽  
Zuzanna Żołek-Tryznowska
Keyword(s):  
Bisphenol A ◽  
Surface Properties ◽  
Rheological Characteristic ◽  
13C Nmr Spectroscopy ◽  
Cyclic Carbonate ◽  
Contact Angles ◽  
Diglycidyl Ether ◽  
Scanning Calorimetry ◽  
Static Contact ◽  
Ft Ir

Poly(hydroxyurethane)s (PHU) are alternatives for conventional polyurethanes due to the use of bis-cyclic dicarbonates and diamines instead of harmful and toxic isocyanates. However, the surface properties of poly(hydroxyurethane)s are not well known. In this work, we focus on the analysis of the surface properties of poly(hydroxyurethane) coatings. Poly(hydroxyurethane)s were obtained by a catalyst-free method from commercially available carbonated diglycidyl ether of bisphenol A (Epidian 6 epoxy resins) and various diamines: ethylenediamine, trimethylenediamine, putrescine, hexamethylenediamine, 2,2,4(2,4,4)-trimethyl-1,6-hexanediamine, m-xylylenediamine, 1,8-diamino-3,6-dioxaoctane, 4,7,10-trioxa-1,13-tridecanediamine, and isophorone diamine, using a non-isocyanate route. The structures of the obtained polymers were confirmed by FT-IR, 1H NMR and 13C NMR spectroscopy, and thermogravimetric (TGA) and differential scanning calorimetry (DSC) analyses were performed. The rheological characteristic of the obtained polymers is presented. The static contact angles of water, diidomethane, and formamide, deposited on PHU coatings, were measured. From the measured contact angles, the surface free energy was calculated using two different approaches: Owens–Wendt and van Oss–Chaudhury–Good. Moreover, the wetting envelopes of PHU coatings were plotted, which enables the prediction of the wetting effect of various solvents. The results show that in the investigated coatings, a mainly dispersive interaction occurs.

Sign in / Sign up

Export Citation Format

Share Document