Stability of Polymeric Membranes to UV Exposure before and after Coating with TiO2 Nanoparticles

The combination of photocatalysis and membrane filtration in a single reactor has been proposed, since the photocatalytic treatment may degrade the pollutants retained by the membrane and reduce fouling. However, polymeric membranes can be susceptible to degradation by UV radiation and free radicals. In the present study, five commercial polymeric membranes were exposed to ultraviolet (UV) radiation before and after applying a sol–gel coating with TiO2 nanoparticles. Membrane stability was characterized by changes in hydrophilicity as well as analysis of soluble substances and nanoparticles detached into the aqueous medium, and by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and energy-dispersive X-ray spectrometry (EDS) for structural, morphological, and elemental distribution analysis, respectively. The TiO2 coating conferred photocatalytic properties to the membranes and protected them during 6 h of UV radiation exposures, reducing or eliminating chemical and morphological changes, and in some cases, improving their mechanical resistance. A selected commercial nanofiltration membrane was coated with TiO2 and used in a hybrid reactor with a low-pressure UV lamp, promoting photocatalysis coupled with cross-flow filtration in order to remove 17α-ethinylestradiol spiked into an aqueous matrix, achieving an efficiency close to 100% after 180 min of combined filtration and photocatalysis, and almost 80% after 90 min.

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Fullerene-like Nanoparticles of WS2 as a Promising Protection from Erosive Wear of Gun Bore Nozzles

Current Nanoscience ◽

10.2174/1573413715666181217115448 ◽

2020 ◽

Vol 16 (1) ◽

pp. 62-70 ◽

Cited By ~ 1

Author(s):

Narimane Rezgui ◽

Danica Simić ◽

Choayb Boulahbal ◽

Dejan Micković

Keyword(s):

Mass Loss ◽

Solid Lubricant ◽

Erosive Wear ◽

Mechanical Resistance ◽

Protective Function ◽

Protective Layers ◽

Total Mass Loss ◽

Mass Losses ◽

Before And After ◽

Tube Life

Background: Erosive wear causes increase in the bore diameter of firearms barrels and nozzles. Most responsible factors for this erosion are friction and heat generated during the shot. Protection from erosive wear is very important for gun tube life cycle, and various protection methods are used: adding phlegmatizers in gunpowder composition or applying protective layers on the gun bore inner surface. Objective: In this research, a possibility is examined to protect the surface of a nozzle exposed to gunpowder erosion applying a layer of tungsten disulfide fullerene-like nanoparticles, IF-WS2, known as outstanding solid lubricant of a great mechanical resistance. Methods: Nanoparticles on the nozzle surface before and after the gunfire tests were observed using scanning electron microscopy/energy dispersive X-ray spectroscopy. Gunfire tests were performed on designed erosion device. Temperatures in the defined position near the affected surface were measured with thermocouples and compared for the nozzles with and without nanoprotection, as well as the nozzle mass loss after each round. Results: For the sample with IF-WS2 lower temperatures after firing and lower mass losses were observed. Mass loss after first round was 25.6% lower for the sample with protective nanoparticles layer, and the total mass loss was about 5% lower after five rounds. After the first round the nozzle without IF-WS2 was heated up to a temperature which was for 150.8°C higher than the nozzle with IF-WS2. Conclusion: Protective function of IF-WS2 is the most pronounced for the first round. The observed results encourage its further application in firearms gun bores protection.

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Strength Development and Elemental Distribution of Dolomite/Fly Ash Geopolymer Composite under Elevated Temperature

Materials ◽

10.3390/ma13041015 ◽

2020 ◽

Vol 13 (4) ◽

pp. 1015 ◽

Cited By ~ 4

Author(s):

Emy Aizat Azimi ◽

Mohd Mustafa Al Bakri Abdullah ◽

Petrica Vizureanu ◽

Mohd Arif Anuar Mohd Salleh ◽

Andrei Victor Sandu ◽

...

Keyword(s):

Elevated Temperature ◽

Fly Ash ◽

Portland Cement ◽

Ordinary Portland Cement ◽

Raw Materials ◽

Liquid Sodium ◽

Strength Development ◽

Elemental Distribution ◽

Distribution Analysis ◽

Geopolymer Composites

A geopolymer has been reckoned as a rising technology with huge potential for application across the globe. Dolomite refers to a material that can be used raw in producing geopolymers. Nevertheless, dolomite has slow strength development due to its low reactivity as a geopolymer. In this study, dolomite/fly ash (DFA) geopolymer composites were produced with dolomite, fly ash, sodium hydroxide, and liquid sodium silicate. A compression test was carried out on DFA geopolymers to determine the strength of the composite, while a synchrotron Micro-Xray Fluorescence (Micro-XRF) test was performed to assess the elemental distribution in the geopolymer composite. The temperature applied in this study generated promising properties of DFA geopolymers, especially in strength, which displayed increments up to 74.48 MPa as the optimum value. Heat seemed to enhance the strength development of DFA geopolymer composites. The elemental distribution analysis revealed exceptional outcomes for the composites, particularly exposure up to 400 °C, which signified the homogeneity of the DFA composites. Temperatures exceeding 400 °C accelerated the strength development, thus increasing the strength of the DFA composites. This appears to be unique because the strength of ordinary Portland Cement (OPC) and other geopolymers composed of other raw materials is typically either maintained or decreases due to increased heat.

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Imaging and Methotrexate Response Monitoring of Systemic Inflammation in Arthritic Rats Employing the Macrophage PET Tracer [18F]Fluoro-PEG-Folate

Contrast Media & Molecular Imaging ◽

10.1155/2018/8092781 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Durga M. S. H. Chandrupatla ◽

Gerrit Jansen ◽

Elise Mantel ◽

Philip S. Low ◽

Takami Matsuyama ◽

...

Keyword(s):

Systemic Inflammation ◽

Pet Imaging ◽

Ex Vivo ◽

Folate Receptor ◽

Tracer Uptake ◽

Response Monitoring ◽

Distribution Analysis ◽

Pet Tracer ◽

Systemic Inflammatory Disease ◽

Before And After

Background. In rheumatoid arthritis, articular inflammation is a hallmark of disease, while the involvement of extra-articular tissues is less well defined. Here, we examined the feasibility of PET imaging with the macrophage tracer [18F]fluoro-PEG-folate, targeting folate receptorβ(FRβ), to monitor systemic inflammatory disease in liver and spleen of arthritic rats before and after methotrexate (MTX) treatment.Methods. [18F]Fluoro-PEG-folate PET scans (60 min) were acquired in saline- and MTX-treated (1 mg/kg, 4x) arthritic rats, followed by tissue resection and radiotracer distribution analysis. Liver and spleen tissues were stained for ED1/ED2-macrophage markers and FRβexpression.Results. [18F]Fluoro-PEG-folate PET and ex vivo tissue distribution studies revealed a significant (p<0.01) 2-fold lower tracer uptake in both liver and spleen of MTX-treated arthritic rats. Consistently, ED1- and ED2-positive macrophages were significantly (p<0.01) decreased in liver (4-fold) and spleen (3-fold) of MTX-treated compared with saline-treated rats. Additionally, FRβ-positive macrophages were also significantly reduced in liver (5-fold,p<0.005) and spleen (3-fold,p<0.01) of MTX- versus saline-treated rats.Conclusions. MTX treatment reduced activated macrophages in liver and spleen, as markers for systemic inflammation in these organs. Macrophage PET imaging with [18F]fluoro-PEG-folate holds promise for detection of systemic inflammation in RA as well as therapy (MTX) response monitoring.

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Chaotization of Human Systems by Technical Electromagnetic Fields

Handbook of Research on Distributed Medical Informatics and E-Health ◽

10.4018/978-1-60566-002-8.ch035 ◽

2009 ◽

pp. 493-499

Author(s):

Manfred Doepp

Keyword(s):

Magnetic Field ◽

Skin Resistance ◽

Autonomous Systems ◽

Distribution Analysis ◽

Bell Curve ◽

Switching Phenomenon ◽

Significant Difference ◽

Before And After ◽

Reaction Patterns ◽

Synchronization Procedure

In our energy diagnostic department we noticed more and more cases with irrational stimulus-reaction- patterns and with a chaotic regulation state of the autonomous systems. We found an explanation by the ‘Switching phenomenon’. However, in addition to earlier results a new cause came up, it is the electrosmog exposure. We used three criteria to clarify the findings: A) a negative reaction on a pulsating magnetic field, B) a positive reaction on a brain synchronization procedure, and C) the frequency distribution analysis of skin resistance values approximated by a lognormal (order) or by a bell curve (chaos). A retrospective evaluation over 4 years (435 patients) was performed. Results: 1) a positive correlation between the criterium A) and a chaotic tendency in C), and 2) a significant difference between reactions before and after the synchronization procedure B). The hypothesis of an electrosmog-induced chaotization of autonomous systems becomes likely.

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Photocatalytic degradation of alachlor by TiO2 nanoparticles from aqueous solutions under UV radiation

Journal of Experimental Nanoscience ◽

10.1080/17458080.2019.1677891 ◽

2019 ◽

Vol 14 (1) ◽

pp. 116-128

Author(s):

Fatemeh Jamshidi ◽

Mansooreh Dehghani ◽

Saeed Yousefinejad ◽

Aboolfazl Azhdarpoor

Keyword(s):

Aqueous Solutions ◽

Photocatalytic Degradation ◽

Tio2 Nanoparticles ◽

Uv Radiation

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Lipid Profiles in Lyme Borreliosis: A Potential Role for Apheresis?

Hormone and Metabolic Research ◽

10.1055/a-0885-7169 ◽

2019 ◽

Vol 51 (05) ◽

pp. 326-329 ◽

Cited By ~ 2

Author(s):

Richard Straube ◽

Karin Voit-Bak ◽

A. Gor ◽

Til Steinmeier ◽

George P. Chrousos ◽

...

Keyword(s):

Lyme Disease ◽

Membrane Filtration ◽

Clinical Symptoms ◽

Causal Relation ◽

Pilot Trial ◽

Lipid Profiles ◽

Common Causes ◽

Before And After ◽

History Of ◽

Lipids And Lipoproteins

AbstractDyslipidemia and dyslipoproteinemia are common causes of metabolic and cardiovascular diseases. On the other hand, intracellular bacteria, such as Borrelia burgdorferi, utilize host lipids to survive and disseminate within the host. Recent data suggest that elevated lipids are a contributing factor to the maintenance and severity of Lyme disease and its complications. Here we review and discuss the role of lipids in Borreliosis and report on a pilot trial to examine the potential roles of circulating lipids and lipoproteins in patients with Borrelia infection. In this analysis we assessed the clinical and lipid profiles of 519 patients (319 women, 200 men) with a proven history of Lyme disease, before and after an extracorporeal double membrane filtration. Lipid profiles pre- and post-apheresis were analyzed in conjunction with clinical symptoms and parameters of inflammation. Circulating cholesterol, triglycerides, LDL, LP(a), and other inflammatory lipids were significantly reduced after the apheresis, while symptoms of the disorder and bioindexes of inflammation such as CRP improved. Further studies should be initiated to investigate the possibly causal relation between Lyme disease and circulating lipids and to design appropriate therapeutic strategies.

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Modification of Titanium Dioxide Nanoparticles with 3-(Trimethoxysilyl)propyl Methacrylate Silane Coupling Agent

Journal of Chemistry ◽

10.1155/2020/1381407 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Thuy-Chinh Nguyen ◽

Tien-Dung Nguyen ◽

Duc-Toan Vu ◽

Duc-Phuong Dinh ◽

Anh-Hiep Nguyen ◽

...

Keyword(s):

Electron Microscopy ◽

Tio2 Nanoparticles ◽

Coupling Agent ◽

Titanium Dioxide Nanoparticles ◽

X Ray Diffraction ◽

Nano Tio2 ◽

Propyl Methacrylate ◽

Transmission Electron ◽

Before And After ◽

Modification Of Titanium

This paper presents some characteristics, properties, and morphology of TiO2 nanoparticles (nano-TiO2) modified with various contents of 3-(trimethoxysilyl)propyl methacrylate (TMSPM) coupling agent. The treatment process was carried out in ethanol solvent at 50oC using ammonia as a catalyst for hydrolysis reaction of silane to silanol. Infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy, field emission scanning electron microscopy, dynamic light scattering, ultraviolet-visible spectroscopy, and X-ray diffraction methods were used for determination of the characteristics, properties of nano-TiO2 before and after treatment. In addition, the contact angle and grafting efficiency of TMSPM on the surface of TiO2 nanoparticles was also evaluated. The obtained results confirmed that TMSPM was grafted to the TiO2 nanoparticles, the agglomeration of nano-TiO2 was decreased, and surface of TiO2 nanoparticles became hydrophobic after modification by TMSPM.

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The Puncture and Water Resistance of Polyurethane- Impregnated Fabrics after UV Weathering

Polymers ◽

10.3390/polym12010015 ◽

2019 ◽

Vol 12 (1) ◽

pp. 15

Author(s):

Antonella Patti ◽

Domenico Acierno

Keyword(s):

Experimental Data ◽

Uv Radiation ◽

Water Resistance ◽

Uv Light ◽

Crosslinking Agent ◽

Waterborne Polyurethane ◽

Impregnation Method ◽

Polyurethane Dispersion ◽

Spectroscopic Analyses ◽

Before And After

Polyurethane is a polymer adaptable to different scientific and industrial requirements; nevertheless it is also extremely susceptible to UV radiation, which compromises the physical and mechanical functionality. In this framework, our study investigated the effect of waterborne polyurethane dispersion (WPUD) applied to a polyester (PET)-based fabric, through the impregnation method, on the puncturing and water resistance of the pristine material, before and after UV weathering. Results confirmed an increment of both features in the prepared fabrics, attributed to the PUR textile treatment; but a partially loss of the gained properties in the samples due to the UV weathering. In order to improve the efficiency of the impregnating dispersions, in protecting the durability of the treated materials, the addition of different UV light stabilizers, or/and of crosslinking agent into WPUD was also tested. From the experimental data, it can be concluded that formulations based on WPUD, containing both the crosslinker and UV organic absorber, have displayed an increment of their perforation and water resistance for the treated samples with respect to the starting textile, and contemporary have preserved the features against the UV light. Finally, microscopic and spectroscopic analyses have been performed as further characterization techniques of the samples surface.

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