Photoinduced hydrophilicity and photocatalytic decomposition of endocrine-disrupting chemical pentachlorophenol on hollandite

2003 ◽  
Vol 18 (5) ◽  
pp. 1046-1053 ◽  
Author(s):  
Toshiyuki Mori ◽  
Mamoru Watanabe ◽  
Hiromitsu Nakajima ◽  
Masaru Harada ◽  
Kenjiro Fujimoto ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Properties ◽  
Aromatic Compounds ◽  
Photocatalytic Decomposition ◽  
Hydroxyl Groups ◽  
Endocrine Disrupting Chemical ◽  
Oxidative Decomposition ◽  
Uv Illumination ◽  
Endocrine Disrupting ◽  
Photoinduced Hydrophilicity

Surface properties and photocatalytic oxidation reactions on the hollandite-type compound K2Ga2Sn6O16 (KGSO) were examined for photoinduced hydrophilicity and oxidative decomposition of an endocrine-disrupting chemical, pentachlorophenol (C6Cl5OH, PCP), under ultraviolet (UV) illumination. The thin films and mesoporous powders of hollandite were used for examination of surface properties and photocatalysis, respectively. The photoinduced surface property was examined by measurement of the contact angle of water, ortho-chlorophenol (o-C6H4ClOH), and toluene on the surface of KGSO. The contact angle of H2O and o-C6H4ClOH decreased to 0° under UV illumination. The toluene showed little change in contact angle under UV irradiation. It is concluded that the surface of KGSO shows photoinduced hydrophilicity for H2O and aromatic compounds with hydroxyl groups (−OH). In addition, KGSO clearly showed a photo-oxidative decomposition of PCP under weak UV illumination at room temperature. The decomposition speed of C6Cl5OH on KGSO was much faster than that on previous reported nano-sized SnO2 photocatalysts. It is expected that photo-oxidative decomposition of aromatic compound will be controlled by a combination of optimum composition of the hollandite phase and control of the morphology of the hollandite particles. This suggests that hollandite would be a promising photocatalyst for decomposition of aromatic compounds in endocrine-disrupting chemicals.

scholarly journals Endocrine disrupting chemical-associated hair product use during pregnancy and gestational age at delivery: a pilot study

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Emma V. Preston ◽  
Victoria Fruh ◽  
Marlee R. Quinn ◽  
Michele R. Hacker ◽  
Blair J. Wylie ◽  
...  
Keyword(s):  
Preterm Birth ◽  
Black Women ◽  
Pilot Study ◽  
Gestational Age ◽  
Endocrine Disrupting Chemical ◽  
Product Use ◽  
Frequent Use ◽  
Increased Risk ◽  
Endocrine Disrupting ◽  
Gestational Age At Delivery

Abstract Background Prenatal endocrine disrupting chemical (EDC) exposure has been associated with increased risk of preterm birth. Non-Hispanic Black women have higher incidence of preterm birth compared to other racial/ethnic groups and may be disproportionately exposed to EDCs through EDC-containing hair products. However, research on the use of EDC-associated hair products during pregnancy and risk of preterm birth is lacking. Therefore, the objective of this pilot study was to estimate associations of prenatal hair product use with gestational age at delivery in a Boston, Massachusetts area pregnancy cohort. Methods The study population consisted of a subset of participants enrolled in the Environmental Reproductive and Glucose Outcomes (ERGO) Study between 2018 and 2020. We collected self-reported data on demographics and hair product use using a previously validated questionnaire at four prenatal visits (median: 12, 19, 26, 36 weeks’ gestation) and abstracted gestational age at delivery from medical records. We compared gestational age and hair product use by race/ethnicity and used linear regression to estimate covariate-adjusted associations of product use and frequency of use at each study visit with gestational age at delivery. Primary models were adjusted for maternal age at enrollment and delivery method. Results Of the 154 study participants, 7% delivered preterm. Non-Hispanic Black participants had lower mean gestational age at delivery compared to non-Hispanic White participants (38.2 vs. 39.2 weeks) and were more likely to report ever and more frequent use of hair products. In regression models, participants reporting daily use of hair oils at visit 4 had lower mean gestational age at delivery compared to non-users (β: -8.3 days; 95% confidence interval: -14.9, -1.6). We did not find evidence of associations at earlier visits or with other products. Conclusions Frequent use of hair oils during late pregnancy may be associated with shorter gestational duration. As hair oils are more commonly used by non-Hispanic Black women and represent potentially modifiable EDC exposure sources, this may have important implications for the known racial disparity in preterm birth.

Increasing Storage Modulus, Contact Angle and Surface Tension of Airway Mucus Increases Clearance by Simulated Cough Through a Model Trachea

2010 ◽  
Author(s):  
Anpalaki J. Ragavan ◽  
Cahit A. Evrensel ◽  
Peter Krumpe
Keyword(s):  
Surface Tension ◽  
Contact Angle ◽  
Storage Modulus ◽  
Surface Properties ◽  
Respiratory Diseases ◽  
Interactive Effects ◽  
Altered Surface ◽  
Human Trachea ◽  
Tension Increase ◽  
And Storage

Altered surface and viscoelastic material properties of mucus during respiratory diseases have a strong influence on its clearance by cilia and cough. Combined effects of the surface properties (contact angle and surface tension) and storage modulus with relatively unchanged viscosity on displacement of the simulated mucus aliquot during simulated cough through a model adult human trachea is investigated. For the mucus simulants used in this study contact angle and surface tension increase significantly as storage modulus increase while viscosity remains practically unchanged. Displacement of mucus simulant aliquots increased significantly with increasing storage modulus (and contact angle) at a given cough velocity in the range between 5 meters/second (m/s) and 30 m/s with duration 0.3 s. Results suggest that the interactive effects of elasticity and surface properties may help facilitate mucus displacement at low cough velocities.

Effect of low-temperature plasma treatment and γ-irradiation on the surface properties of thin films based on polylactic acid

2020 ◽  
Vol 6 ◽  
pp. 40-55
Author(s):  
N.M. Ivanova ◽  
◽  
E.O. Filippova ◽  
A.N. Aleinik ◽  
V.F. Pichugin ◽  
...  
Keyword(s):  
Thin Films ◽  
Contact Angle ◽  
Low Temperature ◽  
Polylactic Acid ◽  
Surface Properties ◽  
Polar Component ◽  
Low Temperature Plasma ◽  
Plasma Exposure ◽  
Γ Irradiation ◽  
Temperature Plasma

Effects of the low-temperature plasma exposure, γ-irradiation, and joint g-irradiation and plasma exposure on the structure and surface properties of thin films based on polylactic acid (PLA) have been investigated. Films were obtained by the method a solvent-casting. It has been shown that films based on polylactic acid have topographically different sides: a smoother inner side and embossed outer one. PLA films have properties close to those hydrophobic, with a contact angle in the range of 70°-73° regardless of the surface side and belong to a weakly polar materials. The combined effect of plasma and gamma radiation slightly changes the surface topography. The effect of low-temperature plasma on the surface of the films leads to a decrease in the contact angle by 13°-55° (9-11%) and an increase in surface energy due to the polar component. The results of in vivo experiments on rabbits are presented. Biomicroscopy, optical coherence tomography, morphological and electron microscopic examination of the cornea after implantation of initial and radiation and plasma treated films showed that implantation of the films in the anterior chamber is not accompanied by a pronounced inflammatory reaction and increased intraocular pressure, while maintaining the morphological structure of the cornea almost unchanged.

Wood-Polymer Composite Prepared by In Situ Synthesis of Copolymer within Wood and its Dimensional Stability

2010 ◽  
Vol 150-151 ◽  
pp. 1-5
Author(s):  
Yong Feng Li ◽  
Chi Jiang ◽  
Duo Jun Lv ◽  
Xiao Ying Dong ◽  
Yi Xing Liu
Keyword(s):  
Contact Angle ◽  
Porous Structure ◽  
Polymer Composite ◽  
Dimensional Stability ◽  
Value Added ◽  
Hydroxyl Groups ◽  
Wood Polymer ◽  
Volume Swelling ◽  
Wood Polymer Composite

In order to improve the value-added applications of low-quality wood, a novel Wood-Polymer Composite was fabricated by in-situ synthesis of copolymer from monomers within wood porous structure. The structure was characterized with SEM and FTIR, and its dimensional stability was also tested. The SEM observations showed that copolymer filled up wood pores and contact tightly with wood matrix, indicating strong interactions between them. FTIR analysis indicated that when the monomers copolymerized in situ wood porous structure, they also reacted with wood matrix by reaction of hydroxyl groups and ester groups, indicating chemical bond between the two phases, which is agreement with SEM observations. The volume swelling efficiency and contact angle of such composite were higher than those of wood, respectively, indicating good dimensional stability involving volume swelling efficiency and contact angle. Such composite could be potentially applied in fields of construction, traffic and indoor decoration.

Novel Strategy for Antifouling Paints with Zero Endocrine Disrupting Chemical (EDC) Elution based on Interpenetrating Polymer Networks (IPNs)

2005 ◽  
Vol 873 ◽  
Author(s):  
Masanobu Naito ◽  
Takashi Nakai ◽  
Takuma Kawabe ◽  
Kenji Mori ◽  
Daisuke Furuta ◽  
...  
Keyword(s):  
Polymer Networks ◽  
Three Dimensional ◽  
Silica Matrix ◽  
Interpenetrating Polymer Networks ◽  
Repellent Activity ◽  
Antifouling Paints ◽  
Endocrine Disrupting Chemical ◽  
Endocrine Disrupting ◽  
Novel Strategy ◽  
Fouling Organisms

AbstractEnvironmentally friendly organic-inorganic hybrid materials with repellent activity against marine fouling organisms have been developed using interpenetrating polymer networks (IPNs), composed of a three-dimensional silica matrix of tetraethoxysilane (TEOS) and chain-like polymers, such as poly(methylmethacrylate) (PMMA) and poly(vinylacetate) (PVAc). The repellent activity of the IPNs reached a maximum of approximately 90% relative to that of tetrabutyl tin oxide (TBTO). Simple bioassays using blue mussels and algae were used to screen out the adequate proportions of those components.

Study on lignin-free lignocellulosic biomass and PSF-PEG membrane compatibility

BioResources ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 1063-1075
Author(s):  
Abiodun A. Amusa ◽  
Abdul L. Ahmad ◽  
Jimoh K. Adewole
Keyword(s):  
Contact Angle ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Lignocellulosic Biomass ◽  
Biomedical Applications ◽  
Composite Membranes ◽  
Hydroxyl Groups ◽  
Chemical Pretreatment ◽  
Physical And Chemical ◽  
Porosity Measurements

Lignocellulosic biomass was delignified by combining physical and chemical pretreatment techniques. Then, a polysulfone-polyethylene glycol blend, which was compatible with the lignin-free biomass (0 wt% to 3.0 wt%), was used to fabricate composite membranes. The presence of hydroxyl groups after the pretreatment was evaluated via Fourier transform infrared spectroscopy. The rheology of the polymer solutions was assessed via the viscometric method. Also, the hydrophobicity of the fabricated membranes was determined using contact angle and porosity measurements. The fabricated membranes with near superhydrophobic properties (a contact angle of approximately 140°) based on this study revealed that contactor systems and biomedical applications would benefit from this modification.

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