Anti-felting Oxidation Treatment of Cashmere Fibers

Cashmere fiber produces felting during laundering because of its scale. In this work, anti-felting treatment of cashmere fibers was investigated using the potassium permanganate oxidizing method, and the optimum oxidizing treatment parameter was obtained through orthogonal experiment. The fibers felting, tensile property, scale morphology, X-ray photoelectron spectroscopy, and directional frictional effect of oxidized cashmere fibers were also tested. Experimental results showed that optimum anti-felting condition of cashmere fiber was 3g/L potassium permanganate (KMnO4) for 20min under the condition at temperature 50°C and pH3. The felting assembly volume of oxidized cashmere decreased. XPS test showed that hydroxyl group (-OH) content of oxidized cashmere fiber lowed.

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Thermally Induced Superlow Friction of DLC Films in Ambient Air

High Temperature Materials and Processes ◽

10.1515/htmp-2017-0045 ◽

2018 ◽

Vol 37 (8) ◽

pp. 725-731 ◽

Cited By ~ 4

Author(s):

Qunfeng Zeng

Keyword(s):

Photoelectron Spectroscopy ◽

Ambient Air ◽

Friction Model ◽

Repulsive Force ◽

Hydroxyl Group ◽

Thermally Induced ◽

X Ray ◽

Thermally Activated ◽

Charged Interface ◽

Positively Charged

AbstractThermally induced superlow friction (0.008) of diamond-like carbon (DLC) films was achieved in ambient air in the present work. Raman and XPS (X-ray Photoelectron Spectroscopy) measurements and analyses show that superlow friction of the annealed DLC films is involved in the transformation of sp3 to sp2 hybridized carbon during annealing and the tribochemical reactions during sliding. The thermally activated graphitization and oxidation of the annealed DLC films in ambient air is beneficial to form the positively charged interface and achieve the stable superlow friction. A friction model was developed and applied to explain superlow friction, which is attributed to Van de Waals force between graphite layers and the repulsive force between hydroxyl group of graphite oxide and hydrogen terminated DLC films surface.

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Preparation and characterization of polyphenylene sulfide/graphene nanoplatelets composite fibers with enhanced oxidation resistance

High Performance Polymers ◽

10.1177/0954008319867748 ◽

2019 ◽

Vol 32 (4) ◽

pp. 394-405 ◽

Cited By ~ 1

Author(s):

Jian Xing ◽

Zhenzhen Xu ◽

Qing-Qing Ni ◽

Huizhen Ke

Keyword(s):

Oxidation Resistance ◽

Photoelectron Spectroscopy ◽

Melt Spinning ◽

Retention Rate ◽

Graphene Nanoplatelets ◽

Polyphenylene Sulfide ◽

Degree Of Crystallinity ◽

Composite Fibers ◽

Oxidation Treatment ◽

X Ray

Composite masterbatches of polyphenylene sulfide (PPS) with functionalized graphene nanoplatelets (GNPs) were prepared by melt blending via a twin-screw extruder. The structure and morphology of composite masterbatches were characterized by scanning electron microscopy and X-ray diffraction analysis. The PPS/functionalized GNPs composite fibers were then manufactured by a self-made spinning equipment via melt spinning. The oxidation resistance and other properties of PPS composite fibers were also examined. The results showed that the pure PPS fibers exhibited smooth surface, whereas the surface of PPS/functionalized GNPs composite fibers was rough. The addition of functionalized GNPs could be acted as heterogeneous nucleating agents to improve the crystallization and increase the degree of crystallinity. The retention rate of breaking strength of PPS/functionalized GNPs composite fibers could maintain up to 85% after the oxidation treatment. The improvement in the oxidation resistance of PPS/functionalized GNPs composite fibers is the results of comprehensive effects characterized by the X-ray photoelectron spectroscopy analyses. The addition of functionalized GNPs could limit the damage of the C–S group and retard the generation of sulfuryl groups (–SO–) during the oxidation treatment. The chemical combination of the elements sulfur (S) and oxygen (O) could also be restricted, thus weakening the oxidation activity.

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Effect of the Fluorine Substitution for –OH Group on the Luminescence Property of Eu3+ Doped Hydroxyapatite

Crystals ◽

10.3390/cryst10030191 ◽

2020 ◽

Vol 10 (3) ◽

pp. 191 ◽

Cited By ~ 3

Author(s):

Xiaojun Zhang ◽

Qingguo Xing ◽

Lixuan Liao ◽

Yingchao Han

Keyword(s):

Electron Microscopy ◽

Phase Composition ◽

Photoelectron Spectroscopy ◽

Hydroxyl Group ◽

Fluorine Substitution ◽

Luminescence Enhancement ◽

X Ray ◽

Fluoridated Hydroxyapatite ◽

Chemical Structures ◽

Substitution Ratio

In this study, different fluoridated hydroxyapatite doped with Eu3+ ion nanoparticles were prepared by the hydrothermal method. The relationship between luminescence enhancement of Eu3+ ions and a fluorine substitution ratio for hydroxyl group in hydroxyapatite was discussed. Moreover, the effect of fluorine substitution for a hydroxyl group on phase composition, crystallinity, and crystal size was studied. Phase composition and chemical structures were identified by X-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR) Spectroscopy analyses. Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) patterns were performed to analyze the morphology and particle size. X-ray Photoelectron Spectroscopy (XPS) patterns were observed to analyze fluorine substitution for the hydroxyl group and chemical state of Eu3+ ions in fluoridated hydroxyapatite. The results of these experiments indicated that the samples with a different fluorine substitution ratio were prepared successfully by maintaining the apatite structure. With an increasing fluorine substitution ratio, the morphology maintained a rod-like structure but the aspect ratio tended to decrease. XPS patterns displayed that the fluorine replaced the hydroxyl group and brought environmental variation. The fluorine ions could affect the crystal field environment and promote luminescence conversion. There was a linear relationship between the fluorine substitution ratio and luminescence enhancement.

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Improved antibacterial activity of hemp fibre by covalent grafting of quaternary ammonium groups

Royal Society Open Science ◽

10.1098/rsos.201904 ◽

2021 ◽

Vol 8 (3) ◽

Author(s):

Li Chang ◽

Wenjie Duan ◽

Siqi Huang ◽

Anguo Chen ◽

Jianjun Li ◽

...

Keyword(s):

Antibacterial Activity ◽

Quaternary Ammonium ◽

Photoelectron Spectroscopy ◽

Disease Transmission ◽

Hydroxyl Group ◽

X Ray Diffraction ◽

X Ray ◽

Hemp Fibre ◽

Grafting Reaction ◽

Covalent Grafting

In this study, a novel antibacterial hemp fibre grafted with quaternary ammonium groups (HF–GTA), were prepared by alkalization, oxidation, amination and quaternization multistage reactions. The chemical structure and micromorphology of the fibre were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis and X-ray diffraction. The grafting and reaction mechanism proved to be successful, which indicated that the grafting reaction primarily occurred on the hydroxyl group of cellulose and hemicellulose in the hemp fibre, where it retained good fibrous morphology, thermal stability and hygroscopicity. HF–GTA exhibited the best antibacterial activity, where the antibacterial ratios against Escherichia coli and Staphylococcus aureus were 95.41% and 99.64%, respectively. Even after washing 30 times, the antibacterial activity was retained at 89.78% and 91.12%, indicating that HF–GTA was endowed with good washing resistance. The antibacterial activity was owing to the electrostatic reaction reducing the electrochemical potential on the cell membrane, leading to the release of cytoplasmic substances and the dissolution of cells. This study is significantly important for guaranteeing textile quality and preventing disease transmission.

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XPS Analysis of Oxide Formed on the Surface of Co-28Cr-6Mo-1Si Alloy Oxidized at 550°C

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.845.95 ◽

2020 ◽

Vol 845 ◽

pp. 95-100

Author(s):

Phacharaphon Tunthawiroon ◽

Mettaya Kitiwan ◽

Patthranit Wongpromrat ◽

Akihiko Chiba

Keyword(s):

Oxide Film ◽

Photoelectron Spectroscopy ◽

Profile Analysis ◽

Chemical Compositions ◽

Xps Analysis ◽

Depth Profile Analysis ◽

Oxidation Treatment ◽

X Ray ◽

Low Concentrations ◽

Xps Depth Profile

This work investigated the influence of oxidation durations on the formation of oxide on the surface of wrought Co-28Cr-6Mo-1Si alloy. The iso-thermal oxidation was individually performed in air at 550°C for 4, 12 and 24 h. For comparison, the surface of the non-oxidized Co-28Cr-6Mo-1Si alloy was concurrently examined. The chemical compositions of the non-oxidized and oxidized alloys were principally analyzed via X-ray photoelectron spectroscopy (XPS). The XPS results revealed that the surface of the non-oxidized alloy enriched in Cr-oxide. After oxidation treatment, the Co-oxide, existing as Co2+ state was observed coexisting with two Cr-oxide states, Cr3+ and Cr4+. The low concentrations of Mo6+ were also observed on the oxidized alloy surface. With the increase in oxidation durations, the Co-oxide was suppressed by Cr-oxide. The XPS depth profile analysis indicated that the thickness of the oxide film increased with increasing the oxidation duration.

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Retarded Oxide Growth on 4H-SiC(0001) Substrates due to Sacrificial Oxidation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.778-780.562 ◽

2014 ◽

Vol 778-780 ◽

pp. 562-565 ◽

Cited By ~ 1

Author(s):

Takuji Hosoi ◽

Yusuke Uenishi ◽

Yuki Nakano ◽

Takashi Nakamura ◽

Takayoshi Shimura ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Frequency Dispersion ◽

Oxide Thickness ◽

Oxide Semiconductor ◽

Oxidation Treatment ◽

Mos Capacitor ◽

X Ray ◽

Initial Stage ◽

Capacitance Voltage ◽

The Impact

The impact of a sacrificial oxidation treatment on subsequent gate oxide formation on 4H-SiC(0001) substrates was investigated. Although x-ray photoelectron spectroscopy (XPS) analysis revealed that the SiC surface after removing a 40-nm-thick sacrificial oxide by diluted HF solution was almost identical to that of an as-grown epilayer, the subsequent dry O2 oxidation resulted in a thinner SiO2 layer for the sample with the sacrificial oxidation in the ultrathin film regime (~3 nm). The metal-oxide-semiconductor (MOS) capacitor with sacrificial oxidation also exhibited a larger frequency dispersion in capacitance-voltage (C-V) characteristics, indicating that interface property had been degraded. However, when the oxide thickness reached about 10 nm, there was no difference in frequency dispersion with and without sacrificial oxidation. This means that the SiO2 growth in the initial stage of oxidation was significantly affected by the sacrificial oxidation treatment.

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Preparation of Graphite Oxide Containing Different Oxygen-Containing Functional Groups and the Study of Ammonia Gas Sensitivity

Sensors ◽

10.3390/s18113745 ◽

2018 ◽

Vol 18 (11) ◽

pp. 3745 ◽

Cited By ~ 7

Author(s):

Liming Luo ◽

Tongjiang Peng ◽

Mingliang Yuan ◽

Hongjuan Sun ◽

Shichan Dai ◽

...

Keyword(s):

Moisture Content ◽

Functional Groups ◽

Reaction Temperature ◽

Graphite Oxide ◽

Photoelectron Spectroscopy ◽

Raw Material ◽

Hydroxyl Group ◽

Hydroxyl Groups ◽

Gas Sensitivity ◽

X Ray

A series of graphite oxide samples were prepared using the modified Hummers method. Flake graphite was used as the raw material and the reaction temperature of the aqueous solution was changed (0 °C, 30 °C, 50 °C, 60 °C, 70 °C, 80 °C, and 100 °C). X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectral analysis, X-ray photoelectron spectroscopy, and contact angle tests were performed to characterize the structure, chemical bonding, type, and content of oxygen-containing functional groups of the graphite oxide samples. The results showed that the type and content of each oxygen-containing functional group could be controlled by changing the reaction temperature with the addition of water. As the temperature of the system increased, the degree of oxidation of the graphite oxide samples first increased and then decreased. Too high a temperature (100 °C) of the system led to the formation of epoxy groups by the decomposition of some hydroxyl groups in the samples, causing the reduction of oxygen-containing functional groups between the graphite layers, poor hydrophilic properties, and low moisture content. When the system temperature was 50 °C, the interlayer spacing of the graphite oxide samples was at its highest, the graphite was completely oxidized (C/O = 1.85), and the oxygen-containing functional groups were mainly composed of hydroxyl groups (accounting for approximately 28.88% of the total oxygen-containing functional groups). The high content of hydroxyl and carboxyl groups had good hydrophilic ability and showed the highest moisture content. The sample at 50 °C had better sensitivity to ammonia because of its high hydroxyl group and carboxyl group content, with the sample showing an excellent profile when the ammonia concentration was 20–60 ppm.

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