scholarly journals Increasing the Adherence of Metallic Copper to the Surface of Titanium Hydride

2021 ◽  
Vol 5 (4) ◽  
pp. 72
Author(s):  
Vyacheslav Ivanovich Pavlenko ◽  
Andrey Ivanovich Gorodov ◽  
Roman Nikolayevich Yastrebinsky ◽  
Natalia Igorevna Cherkashina ◽  
Alexander Alexandrovich Karnauhov
Keyword(s):  
Titanium Hydride ◽  
Metallic Copper ◽  
Copper Coating ◽  
Adhesive Interaction ◽  
Titanium Sulfate ◽  
Additional Layer ◽  
Before And After ◽  
Mechanism Of Interaction ◽  
Thermal Stability Of ◽  
Copper Shell

Studies have been carried out to increase the adhesive interaction between a titanium hydride substrate and a copper coating. An additional layer containing chemically active groups was created on the surface of the spherical titanium hydride by chemisorption modification. This paper discusses the results of scanning electron microscopy (SEM) using energy-dispersive X-ray spectroscopic mapping of coatings obtained on spherical granules of titanium hydride before and after adsorption modification. The mechanism of interaction of the surface of spherical granules of titanium hydride and titanium sulfate salt is proposed. It is shown that the creation of a chemisorbed layer of hydroxotitanyl and the subsequent electrodeposition of metallic copper contribute to the formation of a multilayer shell of a titanium–copper coating on the surface of spherical titanium hydride granules (≡Ti-O-Cu-) with a high adhesive interaction. Results have been given for an experimental study of the thermal stability of the initial spherical granules of titanium hydride and granules coated with a multilayer titanium-copper shell.

scholarly journals A Continuously Active Antimicrobial Surface Coating Reduces Bioburden in a Healthcare Setting

2020 ◽  
Vol 41 (S1) ◽  
pp. s439-s439
Author(s):  
Valerie Beck
Keyword(s):  
Surface Coating ◽  
Geometric Mean ◽  
Healthcare Setting ◽  
Aerobic Bacteria ◽  
Healthcare Settings ◽  
Additional Layer ◽  
Clostridioides Difficile ◽  
Sustained Reduction ◽  
Before And After ◽  
Healthcare Associated

Background: It is well known that contaminated surfaces contribute to the transmission of pathogens in healthcare settings, necessitating the need for antimicrobial strategies beyond routine cleaning with momentary disinfectants. A recent publication demonstrated that application of a novel, continuously active antimicrobial surface coating in ICUs resulted in the reduction of healthcare-associated infections. Objective: We determined the general microbial bioburden and incidence of relevant pathogens present in patient rooms at 2 metropolitan hospitals before and after application of a continuously active antimicrobial surface coating. Methods: A continuously active antimicrobial surface coating was applied to patient rooms in intensive care units (ICUs) twice over an 18-month period and in non-ICUs twice over a 6-month study period. The environmental bioburden was assessed 8–16 weeks after each treatment. A 100-cm2 area was swabbed from frequently touched areas in patient rooms: patient chair arm rest, bed rail, TV remote, and backsplash behind the sink. The total aerobic bacteria count was determined for each location by enumeration on tryptic soy agar (TSA); the geometric mean was used to compare bioburden before and after treatment. Each sample was also plated on selective agar for carbapenem-resistant Enterobacteriaceae (CRE), vancomycin-resistant enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA), and Clostridioides difficile to determine whether pathogens were present. Pathogen incidence was calculated as the percentage of total sites positive for at least 1 of the 4 target organisms. Results: Before application of the antimicrobial coating, total aerobic bacteria counts in ICUs were >1,500 CFU/100 cm2, and at least 30% of the sites were positive for a target pathogen (ie, CRE, VRE, MRSA or C. difficile). In non-ICUs, the bioburden before treatment was at least 500 CFU/100 cm2, with >50% of sites being contaminated with a pathogen. After successive applications of the surface coating, total aerobic bacteria were reduced by >80% in the ICUs and >40% in the non-ICUs. Similarly, the incidence of pathogen-positive sites was reduced by at least 50% in both ICUs and non-ICUs. Conclusions: The use of a continuously active antimicrobial surface coating provides a significant (P < .01) and sustained reduction in aerobic bacteria while also reducing the occurrence of epidemiologically important pathogens on frequently touched surfaces in patient rooms. These findings support the use of novel antimicrobial technologies as an additional layer of protection against the transmission of potentially harmful bacteria from contaminated surfaces to patients.Funding: Allied BioScience provided Funding: for this study.Disclosures: Valerie Beck reports salary from Allied BioScience.

scholarly journals Static and Dynamic Behavior of Polymer/Graphite Oxide Nanocomposites before and after Thermal Reduction

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1008
Author(s):  
Kiriaki Chrissopoulou ◽  
Krystalenia Androulaki ◽  
Massimiliano Labardi ◽  
Spiros H. Anastasiadis
Keyword(s):  
Graphite Oxide ◽  
Thermal Reduction ◽  
Polymer Chains ◽  
Solid Surfaces ◽  
Relaxation Processes ◽  
Thermal Transitions ◽  
Reduced Graphite Oxide ◽  
Before And After ◽  
Similarities And Differences ◽  
Thermal Stability Of

Nanocomposites of hyperbranched polymers with graphitic materials are investigated with respect to their structure and thermal properties as well as the dynamics of the polymer probing the effect of the different intercalated or exfoliated structure. Three generations of hyperbranched polyester polyols are mixed with graphite oxide (GO) and the favorable interactions between the polymers and the solid surfaces lead to intercalated structure. The thermal transitions of the confined chains are suppressed, whereas their dynamics show similarities and differences with the dynamics of the neat polymers. The three relaxation processes observed for the neat polymers are observed in the nanohybrids as well, but with different temperature dependencies. Thermal reduction of the graphite oxide in the presence of the polymer to produce reduced graphite oxide (rGO) reveals an increase in the reduction temperature, which is accompanied by decreased thermal stability of the polymer. The de-oxygenation of the graphite oxide leads to the destruction of the intercalated structure and to the dispersion of the rGO layers within the polymeric matrix because of the modification of the interactions between the polymer chains and the surfaces. A significant increase in the conductivity of the resulting nanocomposites, in comparison to both the polymers and the intercalated nanohybrids, indicates the formation of a percolated rGO network.

scholarly journals Polystyrene/Montmorillonite Nanocomposites: Study of the Morphology and Effects of Sonication Time on Thermal Stability

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Mashael Alshabanat ◽  
Amal Al-Arrash ◽  
Waffa Mekhamer
Keyword(s):  
Electron Microscopy ◽  
Thermal Stability ◽  
Solution Method ◽  
Sonication Time ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Polystyrene Matrix ◽  
Before And After ◽  
Silicate Layers ◽  
Thermal Stability Of

Polymer nanocomposites of polystyrene matrix containing 10% wt of organo-montmorillonite (organo-MMT) were prepared using the solution method with sonication times of 0.5, 1, 1.5, and 2 hours. Cetyltrimethylammonium bromide (CTAB) is used to modify the montmorillonite clay after saturating its surface with Na+ions. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to characterize the montmorillonite before and after modification by CTAB. The prepared nanocomposites were characterized using the same analysis methods. These results confirm the intercalation of PS in the interlamellar spaces of organo-MMT with a very small quantity of exfoliation of the silicate layers within the PS matrix of all samples at all studied times of sonication. The thermal stability of the nanocomposites was measured using thermogravimetric analysis (TGA). The results show clear improvement, and the effects of sonication time are noted.

NATURAL RUBBER/MICROCRYSTALLINE CELLULOSE COMPOSITES WITH EPOXIDIZED NATURAL RUBBER AS COMPATIBILIZER

2019 ◽  
Vol 92 (2) ◽  
pp. 378-387 ◽  
Author(s):  
Kumarjyoti Roy ◽  
Subhas Chandra Debnath ◽  
Aphiwat Pongwisuthiruchte ◽  
Pranut Potiyaraj
Keyword(s):  
Natural Rubber ◽  
Microcrystalline Cellulose ◽  
Interfacial Interaction ◽  
Probable Mechanism ◽  
Mechanical And Thermal Properties ◽  
Solvent Uptake ◽  
Cellulose Composites ◽  
Mechanism Of Interaction ◽  
Thermal Stability Of ◽  
Rubber Filler

ABSTRACT An exploration of the effect of epoxidized NR with 50 mole% epoxide groups (ENR-50) as compatibilizer on the rubber–filler interaction of microcrystalline cellulose (MCC)-filled NR composites was conducted. The compatibilizing efficiency of ENR-50 was systematically examined in terms of cure and mechanical and thermal properties of NR/MCC composites. ENR-50 compatibilized NR/MCC composites showed moderate enhancement in the maximum rheometric torque and tensile properties compared to either uncompatibilized NR/MCC composite or unfilled NR system. The solvent uptake measurements indicated improved interfacial interaction between NR matrix and MCC in presence of ENR-50 as compatibilizer. A thermogravimetric analysis confirmed excellent improvement in the thermal stability of NR/MCC composite in the presence of ENR-50 as compatibilizer. Fourier transform infrared spectroscopy was used to explain the probable mechanism of interaction between NR matrix and MCC in the presence of ENR-50.

scholarly journals Improving the radiation-thermal stability of titanium hydride

2020 ◽  
Vol 1515 ◽  
pp. 022002
Author(s):  
R N Yastrebinsky ◽  
A A Karnauhov ◽  
A V Yastrebinskaya
Keyword(s):  
Thermal Stability ◽  
Titanium Hydride ◽  
Thermal Stability Of

scholarly journals Synthesis of Copper Nanoparticles Coated with Nitrogen Ligands

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Rubén Sierra-Ávila ◽  
Marissa Pérez-Alvarez ◽  
Gregorio Cadenas-Pliego ◽  
Carlos Alberto Ávila-Orta ◽  
Rebeca Betancourt-Galindo ◽  
...  
Keyword(s):  
Copper Nanoparticles ◽  
Metallic Copper ◽  
Good Alternative ◽  
Average Particle ◽  
Chemical Methods ◽  
Nitrogen Ligands ◽  
Copper Sulfate Pentahydrate ◽  
Wet Chemical ◽  
High Yields ◽  
Thermal Stability Of

The synthesis of copper nanoparticles was studied by wet chemical methods using copper sulfate pentahydrate (CuSO4·5H2O) and nitrogen ligands allylamine (AAm) and polyallylamine (PAAm) as stabilizers. The results suggest that the use of these ligands leads to the exclusive formation of metallic copper nanoparticles (Cu-NPs). The use of partially crosslinked polyallylamine (PAAmc) leads to nanoparticles (NPs) with low yields and high coating content, while linear PAAm leads to NPs with high yields and low coating content. The chemical composition of the particles was determined by XRD and average particle diameters were determined by the Debye-Scherrer equation. TGA analysis provided evidence of the content and thermal stability of the coating on the nanoparticles and PAAm. The morphology, particle size distribution, and presence of PAAm coating were observed through TEM. The use of AAm in the synthesis of NPs could be a good alternative to reduce costs. By using TGA, TEM, and DSC techniques, it was determined that synthesized NPs with AAm presented a coating with similar characteristics to NPs with PAAm, suggesting that AAm underwent polymerization during the synthesis.

Thermal Stability of Thermal Interface Pastes, Evaluated by Thermal Contact Conductance Measurement

2000 ◽  
Vol 123 (3) ◽  
pp. 309-311 ◽  
Author(s):  
Xiangcheng Luo, ◽  
Yunsheng Xu, and ◽  
D. D. L. Chung
Keyword(s):  
Sodium Silicate ◽  
Thermal Contact ◽  
The Other ◽  
Thermal Contact Conductance ◽  
Conductance Measurement ◽  
Thermal Interface ◽  
Contact Conductance ◽  
Before And After ◽  
Heating Up ◽  
Thermal Stability Of

Thermal interface pastes based on silicone, lithium doped polyethylene glycol (PEG), and sodium silicate were evaluated in their performance before and after heating up to 120°C. The thermal contact conductance of any of the pastes between copper disks decreased after heating, such that the fractional decrease was less for the silicone-based paste than the PEG-based and sodium-silicate-based pastes. Nevertheless, the conductance was lower for the silicone-based paste than the other pastes both before and after heating up to 100 cycles.

Thermal Aging Analysis of Rubber Used for Fabric Expansion Joints

2013 ◽  
Vol 807-809 ◽  
pp. 2718-2721
Author(s):  
Li Na Ma ◽  
Yu Zeng Zhao ◽  
Hong Hua Ge ◽  
Kuai Ying Liu
Keyword(s):  
Thermal Stability ◽  
Thermal Aging ◽  
Inert Atmosphere ◽  
Expansion Joints ◽  
Chemical Structures ◽  
Before And After ◽  
The Difference ◽  
Ethylene Propylene Diene Terpolymer ◽  
Thermal Stability Of ◽  
Accelerated Thermal Aging

Several kinds of rubbers used for fabric expansion joints were studied by Thermogravimetric analysis under inert atmosphere before and after artificial accelerated thermal aging. The results showed that because of the difference of the chemical structures, the rubber aging is different. And the thermal stability of Polytetrafluoroethylene (PTFE) was obviously higher than that of other two kinds of rubbers, ethylene-propylene-diene-terpolymer rubber (EPDM) and fluororubber.

scholarly journals Mussel-inspired Coating of α-AlH3: A Compact Structure with Highly Enhanced Stability

2022 ◽  
Author(s):  
Mingna Qin ◽  
Bingjie Yao ◽  
Qiang Shi ◽  
Wang Tang ◽  
Shaoli Chen ◽  
...  
Keyword(s):  
Absorption Rate ◽  
Moisture Absorption ◽  
Crystal Form ◽  
Potential Method ◽  
Xps Analysis ◽  
Compact Structure ◽  
Before And After ◽  
The Stability ◽  
Thermal Stability Of ◽  
Enhanced Stability

Abstract we present a novel surfacing coating to resolve the stability of α-AlH3. Inspired by the strong chemical adhesion of mussels, the polymerization of dopamine was first introduced to coat α-AlH3 through a simple situ polymerization. The α-AlH3 was used as a substrate. In-depth characterizations confirmed compact formation with PDA on α-AlH3 surface. The coated α-AlH3 sample was characterized by XRD XPS and SEM . The results show that a strong PDA film is formed on the surface of α-AlH3, the PDA@α-AlH3 retained primary morphology. The crystal form of α-AlH3 does not change after coated by PDA. The results of XPS analysis show that N1s appears on the material after coated by PDA, indicating that polydopamine is formed on the surface of α-AlH3. The moisture absorption tests show that the moisture absorption rate of α-AlH3 is greatly reduced after being coated with PDA. The excellent intact ability of PDA prevent α-AlH3 reacting with watered in the air. The thermal stability of α-AlH3 before and after coating was analyzed by DSC. This work demonstrates the successful applications of dopamine chemistry to α-AlH3, thereby providing a potential method for the metastable materials.

scholarly journals A Reconsideration of the Effect of Procyanidin on the Assembly of Collagen Type I

2018 ◽  
Author(s):  
Y. Wang ◽  
L. Jin
Keyword(s):  
Collagen Type I ◽  
Type I ◽  
Cd Spectra ◽  
Effect Mechanism ◽  
Atomic Force ◽  
Before And After ◽  
Collagen Molecules ◽  
Exact Effect ◽  
Positive Effect ◽  
Thermal Stability Of

ABSTRACTIn order to elucidating the exact effect mechanism of polyphenols on the assembly of collagen, the assembled architectures of collagen treated with different amounts of procyanidin (PA) were investigated in details. The assembled morphologies of collagen were greatly influenced by the content of PA according to atomic force microcopy (AFM) images. When the content of PA was more than 20% (w/w), the fibrillar morphologies were substituted by globular aggregates, which were driven by the intense hydrogen bonding action originating from PA. While the formation of the non-fibrous aggregates was due to the coiling and entangling of flexible collagen molecules rather than their gelatinization based on the appearance of typical adsorption peaks at 222nm and 197nm on circular dichroism (CD) spectra. After being crosslinked by glutaraldehyde (GA), not only the diameters but also the lengths of fibrils increased. Unfortunately, the fibrillogenesis was still inhibited when the collagen suffered from 20% PA firstly and then 4% GA. Conversely, the fibrous morphologies of the fibrils stabilized by 4% GA and then underwent 20% PA maintained well, in spite of accompanying with grievous intertwining. This difference was derived from the change of flexibilities of collagen before and after being crosslinked by GA. Additionally, the differential scanning calorimeter (DSC) analysis confirmed the PA had no positive effect on the improvement of thermal stability of hydrous collagen, whereas the denaturation temperature of hydrated collagen stabilized by 4% GA increased from 40 °C to 80 °C.

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