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Tris [2-phenylpyridinato-C2, N]iridium(III) ( I r (p p y) 3 ) thin films were deposited by thermal evaporation technique at room temperature. These films were examined before and after being irradiated by ultraviolet (UV) radiation for 5, 30, and 60 min. The structural analysis of powder, pristine, and UV-irradiated films has been investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and infrared spectroscopy. The crystallite size values for pristine and irradiated films are examined using XRD spectra. Furthermore, these data correspond with the data of SEM images which supports the impact of UV radiation on the change of surface aggregation. Three distinct bands can be observed on the absorption spectrum of the films under study: the Soret (B-band), N-band, and C-band, with absorption maxima at 3.67, 4.56, and 4.80 eV, respectively. After 60 min. of the radiation exposure, the optical gap, Eg was slightly changed by approximately 0.18 eV. A few important optical characteristics for the pristine film have been calculated, including the strength of the electronic dipole (q2), the molar-extinction coefficient (ξmolar), the strength of the oscillator (f) for pristine and UV–irradiated films. Ir(ppy)3 film displays homogeneity even after UV irradiation, making them suitable for optoelectronic devices such as UV photodetectors. [ABSTRACT FROM AUTHOR]

Biodegradable films based on a blend of Peruvian tunta starch (TS) and tara gum (TG) (95:5) reinforced with TS nanocrystals (NC) were prepared using the casting method. The effect of ultraviolet (UV)-irradiation time (60 and 120 min) and the NC concentration (0, 5, and 10 g/100 g biopolymers) on the physicochemical and disintegrability properties of nanocomposite TS:TG films were investigated. Tensile strength and Young's modulus were increased from 4 to 14 MPa and 14 to 600 MPa, respectively; meanwhile, the elongation was reduced by about 90% by increasing NC amount, mainly at lower UV-time. The color parameters and the UV–vis light barrier showed a significant (p <.05) variation mainly due to the NC effect. The higher the NC content, the lower the moisture barrier (p <.05). Neither NC nor UV time significantly impacted the moisture content, water solubility, crystallinity, or chemical composition. SEM micrographs showed a roughness increase in the films' microstructure with a marked difference among treatments. All films were disintegrated more than 80% after 5 days of burying under composting conditions. The UV-irradiation combined with TS nanocrystal reinforcement caused a significant enhancement of some TS:TG films' properties, suggesting their possible use as eco-friendly packaging. [ABSTRACT FROM AUTHOR]

It is widely recognized that polyester (PET) fibers with swelling properties are necessary for advanced applications of PET fibers in waterproof fabrics. This study presented the UV‐initiated methods to graft polyacrylamide (PAM) hydrogel on the surface of PET fibers. In the one‐step method, PET fibers are impregnated with a mixed solution of the photoinitiator benzophenone (BP) and the monomer acrylalkylamine (AM). Then, the PET fiber was directly exposed to UV light. In the two‐step method, PET fibers were first impregnated with a photoinitiator solution to generate BP radicals. Then, the fibers impregnated with a monomer solution before being grafted by UV light. Both two methods ultimately achieve PAM gelation‐modified PET fibers. The chemical composition and surface structure were detected by Fourier transform infrared spectroscopy and scanning electron microscope. The findings demonstrate that the PAM hydrogel was successfully grafted on the PET fibers through one‐step method or a two‐step method. In addition, the properties of the grafted PET fibers were evaluated by grafting yield, contact angle, and swelling test. The study indicated that the modified PET fibers via a two‐step method exhibited a superior grafting yield up to 29.3% (PET‐2n) and 54% (PET‐2) compared to the one‐step technique (PET‐1). It was shown that the grafting efficacy of PET fibers modified by two‐step method is better than one‐step method. The static contact angles of PET fibers by UV‐Induced were all reduced. For instance, the contact angles of PET‐2n were decreased from 115° to 62.9°; and the two‐step modified PET fiber after acetone cleaning (PET‐2) decreased from 115° to 60°. It was suggested that the hydrophilicity of the modified PET fibers significantly increased. In addition, the research shows that the gelation‐modified fibers were all possessed swelling properties. [ABSTRACT FROM AUTHOR]

Abstract Background Admission to a room previously occupied by patients carrying environmentally robust pathogens implies an increased risk of acquiring those pathogens. Therefore, ‘No-touch’ automated room disinfection systems, including devices based on UV-C irradiation, are discussed to improve terminal cleaning. It is still unclear if clinical isolates of relevant pathogens behave differently under UV-C irradiation compared to laboratory strains used in the approval process of disinfection procedures. In this study we analysed the susceptibility of well characterized clonally divergent vancomycin-resistant enterococci (VRE) strains, including a linezolid-resistant isolate, against UV-C radiation. Methods Susceptibility against UV-C of ten clonally divergent clinical isolates of VRE was determined in comparison to the commonly used test organism Enterococcus hirae ATCC 10541. Ceramic tiles contaminated with 105 to 106 colony forming units/25 cm² of the different enterococci were positioned at a distance of 1.0 and 1.5 m and irradiated for 20 s, resulting in a UV-C dose of 50 and 22 mJ/cm², respectively. Reduction factors were calculated after quantitative culture of the bacteria recovered from treated and untreated surfaces. Results Susceptibility to UV-C varied considerably among the strains studied, with the mean value of the most robust strain being up to a power of ten lower compared to the most sensitive strain at both UV-C doses. The two most tolerant strains belonged to MLST sequence types ST80 and ST1283. The susceptibility of the laboratory strain E. hirae ATCC 10541 ranged between the most sensitive and most tolerant isolates for both irradiation doses. However, for UV-C dose of 22 mJ/cm², the reduction of the most tolerant isolate of ST1283 was statistically significantly lower compared to E. hirae ATCC 10541. The most susceptible strains belonged to the MLST sequence types ST117 and ST203. Conclusions These results indicate that UV-C doses reported in the literature are sufficient for the reduction of commonly used reference strains of enterococci but could be insufficient for the reduction of tolerant patient VRE-isolates in a hospital setting. Therefore, for future studies, the most tolerant clinical isolates should be used to validate automated UV-C devices or longer exposure times should be expected to ensure efficacy in the real world.

It has been established that UV radiation in doses of 453–6040 J/m2 has an effect on the decrease in the specific activity of free papain. Adsorption immobilization on a matrix of medium-molecular (200 kDa), high-molecular (350 kDa), and food (<100 kDa) chitosans and chitosan succinate promotes an increase in the stability of papain molecules with respect to UV irradiation in the dose range from 151 to 6040 J/m2 compared to the free enzyme. Modifications in the IR spectra of immobilized papain practically do not affect the bands caused by the protein component of the system: amide I, amide II, and amide III, so it can be postulated that the chitosan and chitosan succinate matrix act as a photoprotector for immobilized papain. The results obtained can be useful for pharmacology and medicine in the development of drugs that promote accelerated healing of the skin, as well as in the selection of conditions for UV sterilization of drugs containing papain. [ABSTRACT FROM AUTHOR]

L-ascorbic acid (LAA) and D-isoascorbic acid (DIAA) are two of the most important antioxidants in industrialized fruit products as mixed fruit juices, fruit concentrates, and jams, in which they are added as antioxidants and as a nutrient. Despite that, LAA may undergo oxidative- and photo-degradation during storage, compromising its concentration and activities in these food products. In this work we aimed to optimize a method for the identification and quantification of LAA and DIAA by high performance liquid chromatography with diode-array detection (HPLC-DAD) using a NH2 column and a pre-heated mobile phase. A further aim was to investigate if food packing actually protects fruit juices against LAA photodegradation. For the UV photostability test, samples were UV-irradiated at 1416 μW cm−2, at 28 ± °C, and with a radiation energy above 200 W h m−2. The optimized HPLC method provided complete peak resolution of vitamin C isomers in less than nine min run-time. At the end of photostability tests with fruit juices and jellies packaged in polyethylene terephthalate and glass bottles or flasks, L-ascorbic acid was undetectable, suggesting that the packages did not provide effective protection against vitamin C photodegradation. To the best of our knowledge, vitamin C photostability in fruit products was previously unreported.

Background: Admission to a room previously occupied by patients carrying environmentally robust pathogens implies an increased risk of acquiring those pathogens. Therefore, 'No-touch' automated room disinfection systems, including devices based on UV-C irradiation, are discussed to improve terminal cleaning. It is still unclear if clinical isolates of relevant pathogens behave differently under UV-C irradiation compared to laboratory strains used in the approval process of disinfection procedures. In this study we analysed the susceptibility of well characterized clonally divergent vancomycin-resistant enterococci (VRE) strains, including a linezolid-resistant isolate, against UV-C radiation. Methods: Susceptibility against UV-C of ten clonally divergent clinical isolates of VRE was determined in comparison to the commonly used test organism Enterococcus hirae ATCC 10541. Ceramic tiles contaminated with 105 to 106 colony forming units/25 cm² of the different enterococci were positioned at a distance of 1.0 and 1.5 m and irradiated for 20 s, resulting in a UV-C dose of 50 and 22 mJ/cm², respectively. Reduction factors were calculated after quantitative culture of the bacteria recovered from treated and untreated surfaces. Results: Susceptibility to UV-C varied considerably among the strains studied, with the mean value of the most robust strain being up to a power of ten lower compared to the most sensitive strain at both UV-C doses. The two most tolerant strains belonged to MLST sequence types ST80 and ST1283. The susceptibility of the laboratory strain E. hirae ATCC 10541 ranged between the most sensitive and most tolerant isolates for both irradiation doses. However, for UV-C dose of 22 mJ/cm², the reduction of the most tolerant isolate of ST1283 was statistically significantly lower compared to E. hirae ATCC 10541. The most susceptible strains belonged to the MLST sequence types ST117 and ST203. Conclusions: These results indicate that UV-C doses reported in the literature are sufficient for the reduction of commonly used reference strains of enterococci but could be insufficient for the reduction of tolerant patient VRE-isolates in a hospital setting. Therefore, for future studies, the most tolerant clinical isolates should be used to validate automated UV-C devices or longer exposure times should be expected to ensure efficacy in the real world. [ABSTRACT FROM AUTHOR]

The construction site is the leader in the number of injuries, among which a significant proportion are falls from a height. When carrying out work at height, PPE (personal protection equipment) and CPE (collective protection equipment) are used, which can be made of metal or synthetic polymers. Unlike metals, synthetic polymers are less resistant to processes occurring when working in atmospheric conditions. The aim of the work is to increase the safety of PPE users and attract more people related to occupational safety to the problem. In the course of the work, articles containing information about the processes occurring in polymer synthetic materials were analyzed. Data were obtained on the relationship of these processes to each other and their combined effect on the rate of change in the chemical composition of the material. In the end, conclusions were drawn about the deterioration of the physico-chemical properties of materials after exposure to weathering condition.

Optical isomers of short peptide Lysine-Tryptophan-Lysine (Lys-{L/D-Trp}-Lys) and Lys-Trp-Lys with an acetate counter-ion were used to study photoinduced intramolecular and intermolecular processes of interest in photobiology. A comparison of L- and D-amino acid reactivity is also the focus of scientists' attention in various specialties because today, the presence of amyloid proteins with D-amino acids in the human brain is considered one of the leading causes of Alzheimer's disease. Since aggregated amyloids, mainly Aβ42, are highly disordered peptides that cannot be studied with traditional NMR and X-ray techniques, it is trending to explore the reasons for differences between L- and D-amino acids using short peptides, as in our article. Using NMR, chemically induced dynamic nuclear polarization (CIDNP) and fluorescence techniques allowed us to detect the influence of tryptophan (Trp) optical configuration on the peptides fluorescence quantum yields, bimolecular quenching rates of Trp excited state, and the photocleavage products formation. Thus, compared with the D-analog, the L-isomer shows a greater Trp excited state quenching efficiency with the electron transfer (ET) mechanism. There are experimental confirmations of the hypothesis about photoinduced ET between Trp and the CONH peptide bond, as well as between Trp and another amide group. [ABSTRACT FROM AUTHOR]

This study first describes a straightforward approach for the preparation of polymethacrylate‐based networks containing variable amounts of lipoates. For this purpose, butyl methacrylate and a 1,2‐dithiolane derivative of hydroxymethylmethacrylate are copolymerized in different ratios by free‐radical polymerization with the formation of linear network precursors. After optimizing the copolymerization conditions, the ultraviolet (UV)‐induced crosslinking behavior is studied. The latter is possible because of the presence of 1,2‐dithiolane moieties, which can be photolytically cleaved and recombined upon UV‐irradiation. The obtained networks are analyzed in terms of swelling degree, gel fraction, and rheological behavior. Then, network decrosslinking is achieved by immersing the networks in a reducing environment. Finally, successful preliminary coating experiments are conducted, demonstrating the potential applicability of the studied materials. [ABSTRACT FROM AUTHOR]

1-(1-Hydroxy-4-methyl-2-phenylazo)-2-naphthol-4-sulfonic acid is known as Calmagite. In this study, the degradation of Calmagite in H2O2/UV/US, H2O2/US, H2O2, and US processes were investigated separately and each was compared among themselves. The concentration of H2O2, initial dye concentration, pH, UV light, and also ultrasonic sound significantly influenced the degradation of Calmagite and these parameters were optimized. For the azo dye tested, more than 98% of degradation in H2O2/UV/US, H2O2/US, and H2O2 processes was reached in 20, 40, and 60 min, respectively in Britton Robinson buffer media at pH = 11.0. The proposed degradation pathways of Calmagite were established from the ·OH mediated degradation of this azo dye. The first-order rate kinetics best fit the degradation of Calmagite.

Food safety is crucial to the health and life of every individual. Triethylamine and formaldehyde, as key indicators for assessing the freshness of seafood, are increasingly important for food safety. Consequently, this study has developed a dual-gas sensor that is easy to operate and can rapidly detect both formaldehyde and triethylamine. The ZnO-MXene based gas sensors were prepared by a two-step electrostatic adsorption method. Under irradiation with 450 nm LED light, the sensors can detect formaldehyde gas at room temperature. By adjusting the temperature, it is possible to detect 100 ppm triethylamine in the dark at 160 ℃, with a response value of 28.2, which is 5.2 times that of the pure ZnO based sensors. Additionally, it exhibits good selectivity, excellent stability, and reproducibility. This paper also provides a detailed discussion of the sensing mechanism for detecting dual gases. It is significant for the development of dual-gas or multi-gas sensors and has potential applications in food safety testing and addressing complex changes in air environments. [Display omitted] • Unique dual-mode sensor to detect formaldehyde and triethylamine using ZnO/MXene sensing material. • Under UV light triggering and temperature regulation achieved dual gas detection. • Elucidation of sensing mechanism underlying excellent gas selectivity and response. [ABSTRACT FROM AUTHOR]

Cereal grains are a favorable habitat for aflatoxin- producing fungus to develop. the current investigation was carried out to evaluate the quantity and kind of contaminated imported grains and rice generated in the province of Shiraz, Iran. A total of 60 random rice samples were taken from paddy fields in October and November 2020. Aspergillus genera were detected using PCR. HPLC was used to determine the quantity and type of aflatoxin and mycotoxins in samples collected. Irradiation studies were carried out utilizing a collimated beam system with wavelengths ranging from 200 to 360 nm. The quality of rice was assessed using UV light therapy on some of the changed factors, such as amylose content, aroma, and brightness [P 70% decrease seen [P

Kinetic investigations of titanium-containing interpenetrating polymer networks (Ti-IPNs) formation based on cross-linked polyurethane and Ti-containing copolymer (Ti-CP) were carried out using differential calorimetry method. Analysis by the SAXS method revealed that the systems possessed nanosized regions of heterogeneity. The increase of (–TiO2–) fragments content led to increase of both overall level of heterogeneity and of Tg of Ti-СP component. Ti-IPNs are optically transparent with optical transparency coefficient value up to 90–91% at 650 nm. The reverse visible darkening at UV-irradiation was observed for Ti-IPNs, thereby allowing their application in optical data recording on exposure to laser radiation. [ABSTRACT FROM AUTHOR]

This research focuses on novel ecological materials for biomedical and cosmetic applications. The cellulose of bacterial origin is well suited for such purposes, but its functional properties must be modified. In this work, the blends of bionanocellulose and poly(vinyl alcohol), BNC/PVA, were prepared based on in situ and ex situ methodology combined with impregnation and sterilization, using different concentrations of PVA. The main purpose of this work was to check the influence of UV radiation and high temperature, which can be sterilizing factors, on the properties of these mixtures. It was found that the crystallinity degree increases in UV-irradiated samples due to the photodegradation of the amorphous phase. This changes the mechanical properties: the breaking stress and Young's modulus decreased, while the strain at break increased in most UV-irradiated samples. The surface morphology, which we observed by using AFM, did not change significantly after exposure, but the roughness and surface free energy changed irregularly in samples obtained by different methods. However, the effects induced by UV-irradiation were not so crucial as to deteriorate the materials' properties designed for medical applications. Thermogravimetric analysis exhibited good thermal stability for all samples up to at least 200 °C, which allows for the prediction of these systems also in industrial sectors. [ABSTRACT FROM AUTHOR]

Chitosan (Cs) doped with different proportion of copper nanoparticles (CuNPs) has been prepared using the casting method in an oven at T = 333 K. The optical properties of Cs/CuNPs have been investigated using different techniques such as, UV-Vis and FTIR spectroscopy. Many optical parameters such as optical band gap energy, oscillation energy, dispersion energy and lattice dielectric constant of all samples have been estimated. FTIR spectra of Cs and Cs/CuNPs have been investigated and the results revealed that, a broadness of OH groups in Cs/CuNPs has been observed. XRD measurements showed that, average of the particle size is approximately ~ 8.11 nm. Measurements of swelling showed that, the maximum swelling decreases linearly with increasing concentration of copper nanoparticles. The antibacterial activity of chitosan and Cs/CuNPs samples has been investigated against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia colii). The results revealed that, irradiated samples with UV-irradiation exhibited a greater activity in comparison to the non-irradiated samples. [ABSTRACT FROM AUTHOR]

Herein, reduced graphene-oxide-supported ZrO2 and Y2O3 (rGO-ZrO2 and rGO-Y2O3) nanocomposites were synthesized by hydrothermal method and used as the catalysts for photodegradation of picric acid. The structural and morphological properties of the synthesized samples were characterized by using an X-ray diffractometer (XRD), scanning electron microscope (SEM) with energy dispersive absorption X-ray spectroscopy (EDAX), UV-Vis spectrophotometer, Raman spectrophotometer and Fourier transformation infrared spectrophotometer (FT-IR) techniques. In this work, the wide band gap of the ZrO2 and Y2O3 was successfully reduced by addition of the reduced graphene oxide (rGO) to absorb visible light for photocatalytic application. The performance of as synthesized rGO-ZrO2 and rGO-Y2O3 nanocomposites in the photocatalytic degradation of picric acid were evaluated under UV light irradiation. The photodegradation study using picric acid was analyzed with different energy light sources UV (254, 365 and 395 nm), visible light and sunlight at different pH conditions (pH = 3, 7 and 10). The photocatalytic activity of rGO-ZrO2 and rGO-Y2O3 nanocomposites showed excellent photocatalytic activity under optimum identical conditions with mild variations in pH 3. Compared to rGO-Y2O3, the rGO-ZrO2 nanocomposite showed a better action, with a degradation percentage rate of 100, 99.3, 99.9, 100 and 100% for light conditions of UV-252, 365, 395, visible and sunlight, respectively. The excellent degradation efficiency is attributed to factors such as oxygen-deficient metal oxide phase, high surface area and creation of a greater number of hydroxyl groups. [ABSTRACT FROM AUTHOR]

The article describes a new method for synthesizing quantum dots copper sulfide (CuS QDs) based on the UV-irradiation technique (photolysis method). Our process allows producing high-quality, small-size, very low cost and short time. The crystal structure of CuS QDs was characterized using X-ray diffraction (XRD), which confirmed the synthesized sample's hexagonal shape. The structure of the manufactured product was examined using energy-dispersive X-ray spectroscopy (EDX), and the result revealed just copper (Cu) and sulfide (S) elements, indicating that the synthetic material was pure. The morphology, optical properties, and particle size were investigated by photoluminescence spectroscopy (PL), scanning electron microscope (SEM), and transmission electron spectroscopy (TEM). The particles sizes of the CuS QDs were found to be range between 5.4 to 9.1 nm. Finally, this method successfully synthesized CuS QDs through the results. [ABSTRACT FROM AUTHOR]

1-(1-Hydroxy-4-methyl-2-phenylazo)-2-naphthol-4-sulfonic acid is known as Calmagite. In this study, the degradation of Calmagite in H 2 O 2 /UV/US, H 2 O 2 /US, H 2 O 2 , and US processes were investigated separately and each was compared among themselves. The concentration of H 2 O 2 , initial dye concentration, pH, UV light, and also ultrasonic sound significantly influenced the degradation of Calmagite and these parameters were optimized. For the azo dye tested, more than 98% of degradation in H 2 O 2 /UV/US, H 2 O 2 /US, and H 2 O 2 processes was reached in 20, 40, and 60 min, respectively in Britton Robinson buffer media at pH = 11.0. The proposed degradation pathways of Calmagite were established from the OH mediated degradation of this azo dye. The first-order rate kinetics best fit the degradation of Calmagite. [ABSTRACT FROM AUTHOR]

Although evidence suggests that microplastic (MP) particles pose a risk to organisms, the effects of virgin and weathered MP should be evaluated separately as their effects may be different. In this work, we provide new information on the toxic potential of virgin and UV-weathered polyamide, one of the commonly used plastics worldwide. Polyamide MP particles were subjected to UV-weathering in wet conditions over 26 days in a customized irradiation chamber equipped with UV-C light tubes (15Weach, max. wavelength 254 nm). The toxicity of virgin and UV-weathered polyamide MP (< 180 mm in one dimension, 100 and 300 mg L-1) was evaluated by studying Daphnia magna reproduction in natural lake water spiked with MP, following the 21-day OECD 211 test guideline. In parallel, a nonionic surfactant Tween 20 (7 mg L-1) was added to the test medium to improve the suspendability of the MP. The results of the tests showed no adverse effects of either virgin or UV-weathered polyamide MP on the reproduction of D. magna. In addition, presence of Tween 20 in the test medium had no effects on the test Results. These results bring a new perspective on the potential long-term impact of polyamide particles on aquatic organisms, especially considering that the polyamide has received marginal attention in the ecotoxicological research. However, standard test endpoints (survival and reproduction) may still miss long-term adverse effects of insoluble e.g., plastic particles and additional studies may be necessary. [ABSTRACT FROM AUTHOR]

Although evidence suggests that microplastic (MP) particles pose a risk to organisms, the effects of virgin and weathered MP should be evaluated separately as their effects may be different. In this work, we provide new information on the toxic potential of virgin and UV-weathered polyamide, one of the commonly used plastics worldwide. Polyamide MP particles were subjected to UV-weathering in wet conditions over 26 days in a customized irradiation chamber equipped with UV-C light tubes (15 W each, max. wavelength 254 nm). The toxicity of virgin and UV-weathered polyamide MP (< 180 µm in one dimension, 100 and 300 mg L−1) was evaluated by studying Daphnia magna reproduction in natural lake water spiked with MP, following the 21-day OECD 211 test guideline. In parallel, a nonionic surfactant Tween 20 (7 mg L−1) was added to the test medium to improve the suspendability of the MP. The results of the tests showed no adverse effects of either virgin or UV-weathered polyamide MP on the reproduction of D. magna. In addition, presence of Tween 20 in the test medium had no effects on the test results. These results bring a new perspective on the potential long-term impact of polyamide particles on aquatic organisms, especially considering that the polyamide has received marginal attention in the ecotoxicological research. However, standard test endpoints (survival and reproduction) may still miss long-term adverse effects of insoluble e.g., plastic particles and additional studies may be necessary.

The present review attempts to critically examine and evaluate research findings on mushrooms as sources of vitamin D and other nutraceuticals. Recently, there is a growing concern about diseases associated with the deficiency of vitamin D in humans. As people tend to stay indoors, in present times, due to the COVID‐19 pandemic, vitamin D levels are further affected. Research indicates vitamin D as a promising defensive or therapeutic agent against COVID, making this review more crucial. Mushrooms, as a rich source of vitamin D along with various bioactive compounds, perform a significant role in resolving health issues. Robust analyses of various strategies for enhancing vitamin D content in mushrooms holds significance in this study; moreover, this will help stakeholders of the mushroom industry in enriching the overall mushroom quality and human health. Mushroom‐based medicinal formulations and functional foods serve to deliver vitamins and nutrients to humans, thus helping to combat malnutrition and other health problems, especially in developing countries. Evidence from pre‐clinical and clinical analyses suggests that vitamin D2 bioavailability in mushrooms is comparable with vitamin D from other sources. The review also emphasises molecular findings from mushrooms related to genes responsible for morphology and metabolic production of pro‐vitamin‐D2. [ABSTRACT FROM AUTHOR]

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In this study, four ZnO thin films were deposited on FTO substrates using the sol–gel dip coating method to examine their microstructural, morphological, and optical properties through various techniques. Three of them were subjected to ultraviolet (UV) light, magnetic field (MF), and a combination of UV and MF during deposition, referred as ZnO: UV, ZnO: MF, and ZnO: (UV+MF), respectively. The results obtained showed that the simultaneous UV and MF exposure improved the crystallinity and surface homogeneity of the as-deposited film. Moreover, ZnO: (UV+MF) film exhibited an average transparency of 80% in the visible region and a high optical bandgap (3.67 eV). Room-temperature photoluminescence (PL) spectra revealed a weak UV emission and a strong violet emission peaks for all films. However, the violet emission intensity being lower in ZnO: UV and ZnO: MF films due to a reduction in zinc interstitials (Zn _i ) defects, The simultaneous UV and MF exposure did not reduce Zn _i defects, and the violet emission intensity was almost identical to that of the untreated film. These findings suggest that the ZnO: (UV+MF) film can be a promising candidate for the development of ultraviolet and violet lasers and light-emitting diodes.

Microplastics (MPs) are ubiquitously in ecosystem and have evoked wide attention. The potential risk of MPs to the ecosystems is associated with MPs and the additives such as Pb, which serves as a traditional stabilizer. However, the release of Pb from MPs remains largely unknown. In this study, we evaluated the release of Pb from recycled polyvinyl chloride (PVC) under UV-irradiation. The release process was dominated by two processes: H+ facilitated dissolution of Pb, and light-induced hydroxyl radical (·OH) caused C–H bond cleavage from PVC with the generation of alkyl radical. The effects of pH and coexisting low molecular weight organic acids (LMWOAs) were also evaluated. Lower pH speeds up the Pb release from MPs. The LMWOAs act as a filter of UV to restrain the Pb release. Overall, this study shows the release of Pb from recycled PVC MPs and indicates the potential risk of Pb to the environment. [ABSTRACT FROM AUTHOR]

For hydrogen-based energy systems development, purified hydrogen (H2) is a basic requirement and it can be achieved by using the H2-selective membranes. For having H2-selective membranes, it is a decent approach to embed the H2-sensitive materials in the polymeric membranes. Palladium (Pd) is one of the widely used materials for hydrogen-selective membranes due to its strong affinity towards H2 absorption. In the present work, we have used Pd nanoparticles in UV-functionalized track-etched polycarbonate (PC) membranes for better selectivity and permeability of H2 gas. In the UV-irradiation process of membranes, the photo-fries mechanism leads to the C-O bond breaking from the carbonate group of PC molecules and as a result, there is a high number of bond breaking. This phenomenon provides the more active sites for the attachment of Pd nanoparticles in comparison with the pristine PC membrane. The gas permeability of these membranes suggests that the selectivity of H2 over nitrogen (N2) and carbon dioxide (CO2) is increased by the addition of uniformly distributed Pd nanoparticles in the functionalized membranes. [ABSTRACT FROM AUTHOR]

Carrot is one of the most important horticultural crops, with an annual worldwide production exceeding 40 million tonnes. Carrots are sold either fresh intact or fresh-cut as minimally processed vegetables (MPV). In the postharvest supply chain, physiological disorders, fungal decay, and their combinations reduce the quality of fresh intact and MPV carrots. MPV carrots are more susceptible to quality changes than fresh intact carrots due to a higher loss of protective epidermis, greater number of wounded cells, and increased respiration rates. The current review summarizes different environmentally and human-friendly treatments applied in the postharvest supply chain to minimize the adverse effects of handling and storage on physiological disorders and fungal decay. Bitterness, white blush, and browning are the most critical physiological disorders of fresh and MPV carrots. Bitterness can be prevented by storing carrots in well-ventilated rooms without ethylene-producing fruit and vegetables, while white blush and browning can be controlled by the application of heat treatment, ultraviolet (UV)-irradiation, hydrogen sulfide (H 2 S), and edible films. Sclerotinia sclerotiorum , Botrytis cinerea , Alternaria radicina , and Berkeleyomyces spp. (formerly Thielaviopsis spp.) are important fungi causing carrot postharvest losses and waste. Fungal decay of carrots can be controlled by selecting healthy carrots and applying natural compounds, ozone (O 3), heat treatment, UV-irradiation, inorganic salt, and/or biocontrol agents, and their combinations. However, a successful combination of different sustainable treatment methods requires treatment compatibility, and -omics techniques may reveal the best combinations of sustainable treatment methods. [Display omitted] • Sustainable treatments for reducing carrot physiological disorders are discussed. • White blush occurs due to carrot dehydration and structural cell alterations. • Carrot browning can be reduced by the application of abiotic stresses. • Sustainable treatments for preventing carrot decay caused by fungi are discussed. [ABSTRACT FROM AUTHOR]

Strain improvement has become an important strategy in large scale microbial fermentation processes to increase the production yield of enzymes at minimal cost. Here, ultraviolet (UV) irradiation-induced mutant strain of Bacillus cereus, identified using 16S rRNA molecular gene sequencing was subjected to cellulolytic potential screening before cultivating it for carboxymethyl cellulase (CMCase) production under submerged fermentation using a cost-effective plantain stalk–based medium. The enzyme was homogenously purified by a combination of ammonium sulphate precipitation and chromatographic techniques on both DEAE Sephadex A-50 anion-exchange and Sephadex G-100 size-exclusion columns. Sodium dodecyl sulphate polyacrylamide gel electrophoresis was used to determine the molecular weight. Remarkably, this 56 kDa purified cellulase was most active at 70°C and pH 6.0. The CMCase retained over 60% of initial activity after pre-incubation at 60°C for 3 h and was also very stable in both acidic and mild basic medium (pH 3.0-9.0). Cellulase activity was enhanced by Mn2+, Na+, Mg2+ and K+ but inhibited by Pb2+, Hg2+ and Cu2+ at 5 mM. The Km and Vmax of the enzyme with carboxymethyl cellulose are respectively, 3.25 mg/mL and 29.76 U/min/mg. The purified cellulase from B. cereus FOA-2 possesses remarkable properties for suitable application in biotechnological industries.

Polymers containing iminofuran (PIFs) are rarely reported due to the lack of simple and effective synthesis methods. In this work, a novel multicomponent cyclopolymerization (MCCP) of diisocyanides, activated alkynes, and 1,4‐dibromo‐2,3‐butanedione using catalyst‐free one‐pot reactions under mild conditions to prepare PIFs containing bromomethyl groups is reported. PIFs with good solubility and thermal stability are obtained with high Mws (up to 19 600) and good yields (up to 89.5%) under optimized polymerization conditions. The structure of the PIFs is characterized by nuclear magnetic resonance, Fourier transform infrared spectroscopy, and gel permeation chromatography. The photophysical properties indicate that polymers P1a2b3 and P1c2b3 have cluster‐triggered emission characteristics. Thin films made from PIFs quickly degrade under UV irradiation. Moreover, the obtained polymers are decorated with bromomethyl and carboxylate groups in the side chain, which can be postfunctionalized to prepare multifunctional materials, such as star branched polymers and biomedical carrier materials. Thus, this work not only enriches the field of polymerization based on isocyanates and activated alkynes but also provides a facile strategy toward functional iminofuran polymers. [ABSTRACT FROM AUTHOR]

Poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP)‐based gel polymer electrolyte (GPE) is considered one of the promising candidate electrolytes in the polymer lithium ion battery (LIB) because of its free standing, shape versatility, security, flexibility, lightweight, reliability, and so on. However, the pristine PVDF‐HFP GPE cannot still meet the requirement of large‐scale LIBs and other electrochemical devices due to its relatively low ionic conductivity and deterioration of mechanical strength caused by the incorporation of organic liquid electrolyte into the polymer matrix as well as high cost. In order to overcome above deficiencies of PVDF‐HFP based GPE, ultraviolet (UV)‐curable semi‐interpenetrating polymer network is designed and synthesized through UV‐irradiation technique, and the as‐prepared semi‐interpenetrating matrix is constituted by pentaerythritol tetracrylate polymer network and PVDF‐HFP. The ionic conductivity of the optimized GPE is as high as 5 × 10−4 S/cm and electrochemical window is up to 4.8 V at room temperature. Especially, the LIB prepared by GPE shows the high initial discharge specific capacity of 151 mAh/g at 0.5 C and good rate capability. Therefore, the semi‐interpenetrating GPE based on PVDF‐HFP exhibits a promising prospect for the application of rechargeable LIBs. [ABSTRACT FROM AUTHOR]

Storage conditions should be chosen so that they do not affect the action and stability of the active pharmaceutical substance (API), and excipients used in pharmacy. UV irradiation, increased temperature, and relative humidity can decompose storage substances by photolysis, thermolysis, and hydrolysis process, respectively. The effect of physical factors may be the decomposition of pharmaceutical substances or their inappropriate action, including pharmacological effects. Polymers of natural origin are increasingly used in the pharmaceutical industry. With this in mind, we evaluated the effect of storage conditions on the stability of gum arabic (GA) and tragacanth (GT). The influence of higher temperature, UV irradiation, and relative humidity on GA and GT was tested. Thermogravimetry (TG, c-DTA), colorimetric analysis, UV-Vis spectrophotometry, and optical microscopy were used as research methods. The TGA and c-DTA examination indicated that decomposition of GA starts at a higher temperature compared to GT. This indicate that gum arabic is more resistant to higher temperatures compared to tragacanth. However, the conducted analysis showed that gum arabic is more sensitive to the tested storage conditions. Among the tested physical conditions, both polymers were most sensitive to conditions of increased relative humidity in the environment.

This study explores the effectiveness of peanut shell ash (PSA) as a catalyst for the removal of methylene blue (MB) using a synergistic photocatalytic process (UV/Fe-PSA/O3). The color and chemical oxygen demand (COD) removals were studied for ozonation and synergistic process, and the mechanism of the catalytic ozonation synergistic process was explained by studying the production of reactive oxygen species, such as hydroxyl radicals (HR), superoxide ion radicals (SOR), and hydrogen peroxide. The process comparison, scavenger effect, catalyst-dose effect, and pH effect were studied, and a mechanism was proposed. The synergistic process effectively performed 94% decolorization and 72.7% COD removal at pH 6 and 0.1 g Fe-PSA dose at room temperature. The pH studies showed effective performance of synergistic photocatalytic process at pH 4, 6, and 9, respectively, with the maximum efficiency at alkaline pH near the pHPZC of the catalyst. The process efficiency reduction by the addition of scavenger confirms that the UV-irradiated Fe-PSA based ozonation process follows a radical mechanism provoking the production of SORs and HRs. Therefore, it has been found that Fe-PSA/O3 irradiated with UV radiation can act as a cheap alternative process for treating dye composed wastewater. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) nanoparticles were grown on graphene oxide (GO) surface via reflux method. Electrophoretic deposition (EPD) process was employed to deposit graphene oxide/zinc oxide (GO/ZnO) nanocomposite on Al plate with 1 mg/ml of GO/ZnO suspension, 30 V and 3 min. X-ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), energy-dispersive X-ray spectrometry (EDX) and elemental mapping (MAP) investigation were used to characterize the samples. The hydrophobic and hydrophilic behavior of samples were obtained by heat treatment and UV irradiation, respectively. Heat treatment and UV-irradiation affect wettability of samples. Moreover, switchable wettability of samples was investigated. The WCA changes from 5° to 137° by heat treatment and vice versa by UV-irradiation. [ABSTRACT FROM AUTHOR]

Ti-containing interpenetrating polymer networks (Ti-IPNs) based on the cross-linked polyurethane, poly (hydroxyethyl methacrylate) and poly (titanium oxide) have been synthesized. First poly (titanium oxide) was synthesized by sol-gel method in the presence of 2-hydroxyethyl methacrylate at different molar ratio of Ti(OPri)4/H2O. The results of optical spectrophotometry show that the light transmission coefficients (T, %) of titanium-containing interpenetrating polymer networks were of 90,7-91,0% at λ=650 nm. According to EPR data, UV irradiation in the air at room temperature of Ti-IPN samples is accompanied by appearance of signal of paramagnetic centers with broad isotropic signal at g1= 2,010 and also noticeably splitted signals at g2 = 2,003 and g3 =1,967. First and second of them can be ascribed to the oxygen-containing "hole scavenger", while the third one is associated with the Ti3+ paramagnetic ions. The low rate of the electron-hole pair recombination at room temperature in the air demonstrates efficient separation of the charged particles in the hybrid material. Using nitroxyl spin probe (SP) it was revealed that UV-induced charge separation and subsequent charge recombination in Ti-IPNs is accompanied by compaction of macro chains in the hybrid system analysed. The observed changes in the permeability of the Ti-IPN for nitroxyl SP correlate with the measurements of the specific density and the results of the DSC for determining the heat capacity increment (ΔC). [ABSTRACT FROM AUTHOR]

Recent studies have focused on achieving sound osseointegration applying methods of surface reprocessing of dental implants using ultraviolet (UV) irradiation. However, there have been few reports on the effect of UV irradiation on osseointegration in both the short and long term, and experimental studies using the canine model do not exist. Therefore, the aim of this study was to determine the short- and long-term degree of osseointegration of dental implants according to UV irradiation using a histometric analysis in canine models. Four beagles were used for this study and 24 dental implants were placed. Six implants were inserted with flapless protocols in each mandible. Half of the implants were UV-irradiated prior to implantation. UV-treated and untreated implants were placed one after the other; implant stability was recorded using the implant stability test (IST) immediately after implantation and every seven days thereafter. Two of the beagles were sacrificed after four weeks and the other two after 12 weeks. The implants were removed in block sections and were evaluated histomorphologically and statistically. As a result, we found no statistically significant differences in the mean IST values and in bone-to-implant contact (BIC) in all groups at 4 and 12 weeks. [ABSTRACT FROM AUTHOR]

The ultraviolet rays (UV) have several effects on the organism. Especially the epidermis is strongly affected by UV exposure including expression of bioactive peptides. We explore the expression of peptides in the keratinocyte after UV-irradiation. Using peptide mass fingerprinting, we identified the prosecretin among the proteins, which increased after UV-irradiation. In addition, UV exposure induced expression of prosecretin mRNA and secretin-like immunoreactivity analyzed by real-time PCR and enzyme immunoassay, respectively. Moreover, the molecular forms of secretin-like immunoreactivity was evauated with gel filtration chromatography and westernblot analysis, resulting a large molecular forms of secretin-like immunoreactivity which presumed prosecretin by molecular weight. This study showed that UV-irradiation induced expression of prosecretin in keratinocyte. [ABSTRACT FROM AUTHOR]

Hydrogels, integrating diverse biocompatible materials, have emerged as promising candidates for bone repair applications. This study presents a double network hydrogel designed for bone tissue engineering, combining poly(ethylene glycol) diacrylate (PEGDA) and chitosan (CS) crosslinked through UV polymerization and ionic crosslinking. Concurrently, copper-doped mesoporous silica nanospheres (Cu-MSNs) were synthesized using a one-pot method. Cu-MSNs underwent additional modification through in-situ biomineralization, resulting in the formation of an apatite layer. Polydopamine was employed to facilitate the deposition of Calcium (Ca) and Phosphate (P) ions on the surface of Cu-MSNs (Cu-MSNs/PDA@CaP). Composite hydrogels were created by integrating varied concentrations of Cu-MSNs/PDA@CaP (25, 50, 100, 150, 200 μg/mL). Characterization unveiled distinctive interconnected porous structures within the composite hydrogel, showcasing a notable 169.6 % enhancement in compressive stress (elevating from 89.01 to 240.19 kPa) compared to pure PEGDA. In vitro biocompatibility experiments illustrated that the composite hydrogel maintained elevated cell viability (up to 106.6 %) and facilitated rapid cell proliferation over 7 days. The hydrogel demonstrated a substantial 57.58 % rise in ALP expression and a surprising 235.27 % increase in ARS staining. Moreover, it significantly enhanced the expression of crucial osteogenic genes, such as run-related transcription factors 2 (RUNX2), collagen 1a1 (Col1a1), and secreted phosphoprotein 1 (Spp1), establishing it as a promising scaffold for bone regeneration. This study shows how Cu-MSNs/PDA@CaP were successfully integrated into a double network hydrogel, resulting in a composite material with good biological responses. Due to its improved characteristics, this composite hydrogel holds the potential for advancing bone regeneration procedures. [ABSTRACT FROM AUTHOR]

Spent Sulfite Liquor (SSL), a byproduct of sulfite pulp production, contains lignosulfonates (LS) dissolved in a liquid phase rich in sugars, and phenolic substances. This study investigates the effects of UV-irradiation on SSL as a microbial substrate. UV-irradiation of SSL resulted in the polymerization of LS. The molecular weight of LS increased from 1949 Da to 5637 Da (at 3 days of irradiation). FTIR spectroscopy revealed structural changes, including an increase in phenolic OH groups and the formation of β -O-4 ether linkages. Batch fermentations with Actinobacillus succinogenes demonstrated that UV-irradiated SSL led to higher succinic acid production and reduced by-product formation. By product formation was reduced from 0.90 g byproduct per g succinic acid to only 0.62 g in irradiated media. Although the initial lag phase was longer for irradiated SSL, acid production eventually exceeded that of non-irradiated SSL and standard medium. Ultimately, a concentration of 14.40 g L-1 with a yield of 0.56 g of succinic acid per gram of consumed sugar was attained. This represented an increase of 3.01 g L-1 compared to standard media. In conclusion, UV-irradiation upgraded SSL by a higher specificity of succinic acid and allowing better utilization of LS in various applications through polymerization, aligning with sustainable production goals. [Display omitted] • UV-irradiation enhances spent sulfite liquor value. • Irradiated lignosulfonates undergo polymerization and structural changes. • UV-treated sulfite liquor has higher succinic acid yield and reduced by-products. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of monolith via rapid UV -irradiation cryopolymerization. • Better adsorption capacity for Pd(II) in strong acidic condition. • Maximum adsorption capacity for Pd(II) was 155.5 mg g−1. • Have a better stability after temperature treatment and shelf life. • The designed monolith has better selectivity in coexisting metal cations. • Promising adsorption performance for Pd(II) in waste electronic materials. Recovering palladium rapidly and effectively from electronic waste materials presents a challenging and essential task, mainly due to the harsh acidic conditions. This study developed a highly porous and lightweight monolith to address this issue by enabling rapid and efficient palladium adsorption under acidic conditions. The monoliths were fabricated through a quick UV -irradiation cryopolymerization process. The resulting monoliths exhibited significantly enhanced palladium adsorption capacity, measuring at 155.5 mg g−1 , surpassing most previously reported data. The adsorbed concentrations of Pd(II) and other coexisting ions were determined using an Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES, VISTA-MPX, Varian). Various parameters such as pH , contact time, temperature, concentration, and selectivity were investigated to assess their impact on palladium adsorption. The material demonstrated superior selectivity for palladium ions in the presence of coexisting metal ions. Furthermore, the material's thermal stability was evaluated within the 25 – 100 °C range, revealing sufficient adsorption capacity at temperatures up to 100 °C , indicating its potential for implementation in harsh conditions. The synthesized monolith exhibited a shelf life of up to six months without degrading its adsorption performance. Moreover, the material retained its adsorption efficiency after multiple cycles of use. The effectiveness of palladium adsorption was also demonstrated in actual wastewater samples, further validating the material's practical application. Overall, this designed system showcases excellent adsorption performance and stability, making a valuable contribution to polymer chemistry and environmental science for recovering precious metals from wastewater. [ABSTRACT FROM AUTHOR]

In this work, ultraviolet irradiation was employed to assist in the preparation of a novel photocatalyst composite in the form of carbon dots/zeolite-4A/TiO 2 , using coal tailings as the source of silicon-aluminum and carbon. The composite was designed for the degradation of methylene blue under 500 W of UV light irradiation. Zeolite-4A was used as a support for the well-dispersed carbon dots and TiO 2 nanoparticles. The as-prepared composites were subjected to thorough characterization, confirming the successful formation of zeolite-4A with a cube structure, along with the loading of TiO 2 and coal-based CDs in the composites. The experimental results demonstrated that the UV-CZTs nanocomposites exhibited a remarkable removal efficiency of 90.63% within 90 min for MB. The corresponding rate constant was exceptionally high at 0.0331 min−1, surpassing that of the Dark-CZTs and pure TiO 2. This significant enhancement was possibly due to the synergistic effect of adsorption photocatalysis of the UV-CZTs, combined with the excellent electron-accepting capabilities of the coal-based CDs, which led to highly improved charge separation. An investigation of the spent photocatalyst's recyclability revealed that it retained a remarkable 82.94% MB removal efficiency after five consecutive cycles, signifying the stability of the composite. Trapping experiments also elucidated the primary reactive species responsible for MB degradation, which were identified as photo-generated holes and ⸱O 2 − species. By this process, the hydroxyl radicals generated in the system successfully promoted the transformation of coal tailings to coal-based zeolite and coal-based CDs. Coal-based zeolite served as an excellent carrier of titanium dioxide, which improved its dispersibility. The inhibition of e−-h+ recombination of titanium dioxide by introducing coal-based CDs improved the photocatalytic ability of titanium dioxide. Through this study, coal tailings, as a coal processing waste, were transformed into high-value materials, and relevant photocatalytic composite materials could be prepared with broad application prospects. • A novel preparation method of the composite photocatalysts assisted with ultraviolet-irradiation were proposed. • UV-CDs/Zeolite-4A/TiO 2 composite photocatalysts were prepared using coal tailings as silicon-aluminum source and carbon source. • UV-CDs/Zeolite-4A/TiO 2 were the most stable and reusable because zeolite-4A confined TiO 2 on its surface. • The ternary structure of CDs-Zeolite-TiO 2 enhanced the photocatalytic performance of UV-CDs/Zeolite-4A/TiO 2. [ABSTRACT FROM AUTHOR]