scholarly journals Comparative Evaluation of the Photodegradation of Stearic Acid by TiO<sub>2</sub> - Modified Cement Under UV Irradiation Through Water Contact Angle and Absorbance Studies

2020 ◽  
Vol 9 (1) ◽  
pp. 1 ◽  
Author(s):  
Aniedi Nyong ◽  
Edet Nsi ◽  
Joachim Awaka-Ama ◽  
Godwin Udo
Keyword(s):  
Contact Angle ◽  
Stearic Acid ◽  
Water Contact Angle ◽  
Uv Irradiation ◽  
Comparative Evaluation ◽  
Water Contact

Hydrophobic Performance of Core/Shell Nanoarrays Modified by Stearic Acid

2020 ◽  
Vol 15 (2) ◽  
pp. 264-268
Author(s):  
Hongxing Han ◽  
Lin Pan ◽  
Manying Zhang ◽  
Lei Zhao ◽  
Zhifeng Liu
Keyword(s):  
Contact Angle ◽  
Stearic Acid ◽  
Water Contact Angle ◽  
Zno Nanorods ◽  
Hydrophobic Surface ◽  
Optical Transmittance ◽  
Surface Hydrophobicity ◽  
Core Shell ◽  
Water Contact ◽  
Angle Measurements

In this paper, we successfully prepare hydrophobic surface of ZnO/ZnS nanorods arrays modified by stearic acid. The morphology, microstructure, optical transmittance and self-cleaning property are examined by SEM, XRD, UV-vis and water contact angle measurements, respectively. The ZnO/ZnS core/shell nanoarrays shows a higher value of water contact angle in compare with that of pure ZnO nanorods arrays. After treatment by stearic acid, the resulting ZnO/ZnS nanostructure exhibits the best hydrophobicity with water droplets about 146.5 . The results show that the surface hydrophobicity of ZnO/ZnS nanoarrays can be improved by using stearic acid with low-surface-energy.

scholarly journals Influence of Annealing and UV Irradiation on Hydrophilicity of Ag- Nanostructured Thin Films

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Fanming Meng ◽  
Zhaoqi Sun ◽  
Xueping Song
Keyword(s):  
Crystal Structure ◽  
Thin Films ◽  
Contact Angle ◽  
Water Contact Angle ◽  
Uv Irradiation ◽  
Annealing Time ◽  
Irradiation Time ◽  
Ambient Air ◽  
Water Contact ◽  
Nanostructured Thin Films

Ag-TiO2nanostructured thin films with silver content of 5 vol% have been deposited on silicon, glass, and quartz substrates by RF magnetron sputtering and annealed in ambient air at 900°C for 15, 30, 60, 90, and 120 min. Their crystal structure, surface morphology, and hydrophilicity have been characterized by X-ray diffractometer, atomic force microscope, and water contact angle apparatus, respectively. The influence of annealing time and UV irradiation time on hydrophilic property of Ag-TiO2thin films have been studied in detail. It is shown that annealing time influences crystal structure of Ag-TiO2thin films. The unannealed film is amorphous and shows poor hydrophilicity. With the increase of annealing time from 15 to 120 min, the grain-size slowly increases and tends to uniformity. A suitable annealing time can significantly enhance the hydrophilic behavior of Ag-TiO2films. Water contact angle decreases with the increase of irradiation time. The mechanism of hydrophilicity has been proposed and can be attributed to the increase of oxygen anion radicals and reactive center of surface .

Effects of Ultraviolet (UV) Treatment on the Properties of Black Tilapia Fish Skins Gelatin

2020 ◽  
Vol 1010 ◽  
pp. 465-470
Author(s):  
Norhasikin Ismail ◽  
Maizlinda Izwana Idris ◽  
Hasan Zuhudi Abdullah
Keyword(s):  
Contact Angle ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Water Contact Angle ◽  
Uv Irradiation ◽  
Functional Group ◽  
Gel Strength ◽  
Fish Gelatin ◽  
Uv Treatment ◽  
Water Contact

The aim of the study is to investigate the effects of ultraviolet (UV) treatment on the properties of black tilapia fish skins gelatin. The fish gelatin were investigated in terms of gel strength, functional group and the water contact angle of the gelatin. The UV treatment were irradiated with UVA and UVC at different time (0.5, 1.0, 1.5 and 2.0 h). The gel strength of gelatin gel significantly increases after UV irradiation for both UVA and UVC sample. The water contact angle of the gelatin was categorized as hydrophobic for both gelatin that treated with UVA and UVC which the angle >65°. The interactions and characteristic of functional groups for gelatin that treated with UV were analyzed via Fourier Transform Infrared Spectroscopy (FTIR). Results indicated that employing UV irradiation as an alternative method to enhance some of the quality attributes of fish gelatin.

scholarly journals Thermoinduced and Photoinduced Sustainable Hydrophilic Surface of Sputtered-TiO2 Thin Film

Coatings ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1360
Author(s):  
Sangbin Park ◽  
Younghwa Yoon ◽  
Sehyun Lee ◽  
Taejun Park ◽  
Kyunghwan Kim ◽  
...  
Keyword(s):  
Thin Film ◽  
Contact Angle ◽  
Water Contact Angle ◽  
Uv Irradiation ◽  
Tio2 Thin Film ◽  
Maintenance Cost ◽  
Tio2 Films ◽  
Hydrophilic Surface ◽  
Water Contact ◽  
Defect Sites

To achieve self-cleaning at a low maintenance cost, we investigated the possibility of obtaining a sustainable hydrophilic surface of TiO2 thin film. As the hydrophilicity of TiO2 films fabricated by FTS has not yet been studied, we deposited TiOx using FTS, and then TiO2 was formed through additional treatment. Hydrophilic surfaces were obtained by thermoinduced and photoinduced methods. UV irradiation led to the conversion of Ti4+ to Ti3+ in the lattice structure and an increase in the number of OH groups on the surface, and annealing induced the formation of Ti3+ defect sites, as well as organic degradation and changes in the crystal structure. Through the annealing process, the water contact angle of as-deposited film was decreased from 78.7° to 35.7°, and crystallinity changed from amorphous to anatase. These changes contributed to the formation of a hydrophilic surface and reduced the water contact angle by up to 10.8°. After the formation of a hydrophilic surface through annealing and UV irradiation, the sample returned to its original state. We confirmed that the water contact angle of the returned sample was decreased through exposure to sunlight; it reduced the water contact angle of the returned sample by 15.2°. Thus, the results revealed that the crystallinity influences the hydrophilicity and its sustainability for TiO2 films under sunlight.

scholarly journals The Adverse Effects of TiO2 Photocatalycity on Paraloid B72 Hybrid Stone Relics Protective Coating Aging Behaviors under UV Irradiation

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 262
Author(s):  
Wenjuan Li ◽  
Junling Lin ◽  
Yaru Zhao ◽  
Zihe Pan
Keyword(s):  
Contact Angle ◽  
Adverse Effects ◽  
Tio2 Nanoparticles ◽  
Water Contact Angle ◽  
Uv Irradiation ◽  
Protective Coating ◽  
Irradiation Time ◽  
Polymer Coatings ◽  
Angle Measurement ◽  
Water Contact

The incorporation of photocatalytic nanomaterials into polymer coatings is used to protect stone relics from weathering. However, the photocatalytic nanomaterials might generate excess free radicals to degrade the polymer matrix. In this work, a certain amount of TiO2 nanoparticles were dispersed into Paraloid B72 and applied onto sandstone relics to explore the adverse effects of TiO2 nanoparticles on Paraloid B72 under ultraviolet (UV) irradiation. To fulfill this goal, the effects of TiO2 on pore formation and the structure of Paraloid B72 was studied by scanning electron microscopy (SEM). Moreover, the surface chemical composition, pore structure, surface roughness and surface wettability were explored via Fourier transform infrared (FTIR) spectroscopy, SEM, optical profilometer and water contact angle measurement under UV irradiation. Results showed that the incorporation of TiO2 nanoparticles prohibited the generation of pores in Paraloid B72 and there were no pores formed when the content of TiO2 exceeded 0.8 wt%. The water contact angle of origin Paraloid B72 and TiO2/Paraloid B72 decreased with the prolonging UV irradiation. Moreover, TiO2 nanoparticles were extracted from the matrix and the pores cannot be detected with the prolonging UV irradiation time under a higher content of TiO2. These research findings might promote the understanding of using photocatalytic nanomaterials in developing stone relics’ protective coating.

Long-Term Stable Metal Organic Framework (MOF) Based Mixed Matrix Membranes for Ultrafiltration

2020 ◽  
Author(s):  
Muayad Al-shaeli ◽  
Stefan J. D. Smith ◽  
Shanxue Jiang ◽  
Huanting Wang ◽  
Kaisong Zhang ◽  
...  
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Mixed Matrix Membranes ◽  
Recovery Ratio ◽  
Mixed Matrix ◽  
Water Contact ◽  
Membrane Performance ◽  
Metal Organic ◽  
Matrix Membranes

<p>In this study, novel <a>mixed matrix polyethersulfone (PES) membranes</a> were synthesized by using two different kinds of metal organic frameworks (MOFs), namely UiO-66 and UiO-66-NH<sub>2</sub>. The composite membranes were characterised by SEM, EDX, FTIR, PXRD, water contact angle, porosity, pore size, etc. Membrane performance was investigated by water permeation flux, flux recovery ratio, fouling resistance and anti-fouling performance. The stability test was also conducted for the prepared mixed matrix membranes. A higher reduction in the water contact angle was observed after adding both MOFs to the PES and sulfonated PES membranes compared to pristine PES membranes. An enhancement in membrane performance was observed by embedding the MOF into PES membrane matrix, which may be attributed to the super-hydrophilic porous structure of UiO-66-NH<sub>2</sub> nanoparticles and hydrophilic structure of UiO-66 nanoparticles that could accelerate the exchange rate between solvent and non-solvent during the phase inversion process. By adding the MOFs into PES matrix, the flux recovery ratio was increased greatly (more than 99% for most mixed matrix membranes). The mixed matrix membranes showed higher resistance to protein adsorption compared to pristine PES membranes. After immersing the membranes in water for 3 months, 6 months and 12 months, both MOFs were stable and retained their structure. This study indicates that UiO-66 and UiO-66-NH<sub>2</sub> are great candidates for designing long-term stable mixed matrix membranes with higher anti-fouling performance.</p>

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