In this work, the degradation of cefalexin, norfloxacin, and ofloxacin was examined via various advanced oxidation processes (AOPs). Direct photolysis by ultraviolet (UV) and vacuum ultra violet ...(VUV) was less effective for the degradation of fluoroquinolone antibiotics such as norfloxacin and ofloxacin than that of cefalexin. Both hydrogen peroxide (H2O2) and potassium persulfate (K2S2O8) assisted UV/VUV process remarkably enhanced fluoroquinolone degradation. The addition of K2S2O8 was superior to H2O2 under VUV irradiation, with the best removal efficiency of norfloxacin and ofloxacin being almost 100% within 3 min in the presence of VUV/K2S2O8. The ofloxacin degradation rate was accelerated as concentrations of H2O2 and K2S2O8 was increased to 3 mM, but the degradation rate was slightly decreased with excess H2O2 (>3 mM). The performance of modified VUV processes (i.e., VUV/H2O2 and VUV/K2S2O8) was inhibited at highly alkaline condition (pH 11). The co-existence of halides (Cl− and Br−) enhanced antibiotics degradation via the modified VUV processes, but the reaction was almost unaffected in the presence of single halides. This study demonstrated that modified VUV processes (especially VUV/K2S2O8) are efficient for eliminating fluoroquinolone antibiotics from water, which can be considered as a clean and green method for the treatment of antibiotics-containing industrial wastewater.
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•There was greater degradation of CEX, NOF, and OFX by K2S2O8 than H2O2.•The effectiveness of chemical agents was promoted by VUV irradiation.•Co-existence of Cl− and Br− synergistically enhanced the antibiotics degradation.•Optimal concentrations of K2S2O8 and H2O2 were predicted by Box-Behnken analysis.
The variation of the CA of the SPS at −5 °C.
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•The anti-icing behavior of static and dynamic low-temperature droplet on as-prepared surfaces was investigated.•Compared with the HPS, HS ...and pure Cu surface, the SPS had the best anti-icing performance.•This work offers a theoretical guidance for anti-icing application of microelectronic materials.
The anti-icing behavior of static and dynamic low-temperature droplets on the surface of microelectronic material was investigated. The ZnO-coated superhydrophobic surface (SPS), hydrophobic surface (HPS), hydrophilic surface (HS) and pure Cu surface were prepared by hydrothermal method and ultraviolet light irradiation. Under the static and dynamic anti-icing condition, the SPS had excellent anti-icing ability before −20 °C. Even if the temperature was −20 °C, the SPS still have longest delayed icing time when compared with other three surfaces. This work offers a theoretical guidance for anti-icing application of microelectronic materials.
Over the last decade, ultraviolet light-emitting diodes (UV LEDs) have attracted considerable attention as alternative mercury-free UV sources for water treatment purposes. This review is a ...comprehensive analysis of data reported in recent years (mostly, post 2014) on the application of UV LED-induced advanced oxidation processes (AOPs) to degrade organic pollutants, primarily dyes, phenols, pharmaceuticals, insecticides, estrogens and cyanotoxins, in aqueous media. Heterogeneous TiO2-based photocatalysis in lab grade water using UVA LEDs is the most frequently applied method for treating organic contaminants. The effects of controlled periodic illumination, different TiO2-based nanostructures and reactor types on degradation kinetics and mineralization are discussed. UVB and UVC LEDs have been used for photo-Fenton, photo-Fenton-like and UV/H2O2 treatment of pollutants, primarily, in model aqueous solutions. Notably, UV LED-activated persulfate/peroxymonosulfate processes were capable of providing degradation in DOC-containing waters. Wall-plug efficiency, energy-efficiency of UV LEDs and the energy requirements in terms of Electrical Energy per Order (EEO) are discussed and compared. Despite the overall high degradation efficiency of the UV LED-based AOPs, practical implementation is still limited and at lab scale. More research on real water matrices at more environmentally relevant concentrations, as well as an estimation of energy requirements providing fluence-based kinetic data are required.
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•Recent studies on UV LEDs-induced AOPs for water treatment are reviewed.•WPE of UV LEDs is a key parameter for applications.•Most works deal with TiO2-based photocatalysis using UVA LEDs.•UV/PS/PMS, UV/H2O2, photo-Fenton-(like) processes using UVB/UVC LEDs are presented.•Energy efficiency and energy requirements are compared and discussed.
Light-emitting diode (LED) lights have recently been applied in controlled environment agriculture toward growing vegetables of various assortments, including microgreens. Spectral qualities of LED ...light on photosynthesis in microgreens are currently being studied for their ease of spectral optimization and high photosynthetic efficiency. This review aims to summarize the most recent discoveries and advances in specific phytochemical biosyntheses modulated by LED and other conventional lighting, to identify research gaps, and to provide future perspectives in this emerging multidisciplinary field of research and development. Specific emphasis was made on the effect of light spectral qualities on the biosynthesis of phenolics, carotenoids, and glucosinolates, as these phytochemicals are known for their antioxidant, anti-inflammatory effects, and many health benefits. Future perspectives on enhancing biosynthesis of these bioactives using the rapidly progressing LED light technology are further discussed.
Simultaneous removal process of SO2 and NO from flue gas using vacuum ultraviolet light (VUV)/heat/peroxymonosulfate (PMS) in a VUV spraying reactor was proposed. The key influencing factors, active ...species, reaction products and mechanism of SO2 and NO simultaneous removal were investigated. The results show that vacuum ultraviolet light (185 nm) achieves the highest NO removal efficiency and yield of ▪ and ▪ under the same test conditions. NO removal is enhanced at higher PMS concentration, light intensity and oxygen concentration, and is inhibited at higher NO concentration, SO2 concentration and solution pH. Solution temperature has a double impact on NO removal. CO2 concentration has no obvious effect on NO removal. ▪ and ▪ produced from VUV-activation of PMS play a leading role in NO removal. O3 and ·O produced from VUV-activation of O2 also play an important role in NO removal. SO2 achieves complete removal under all experimental conditions due to its very high solubility in water and good reactivity. The highest simultaneous removal efficiency of SO2 and NO reaches 100% and 91.3%, respectively.
•VUV/heat/PMS system was used to simultaneously remove NO and SO2.•▪/▪ produced by VUV activation of PMS play a main role in NO removal.•O3/▪ produced by VUV activation of O2 play an important role in NO removal.
•Synthesis of a low molecular weight PS incorporating a photostabilizer additive.•The synthesized copolymer was used as a macroadditive in films of PS, HIPS and ABS.•The macroadditive did not cause ...significant changes in mechanical properties.•A mitigation of UV accelerated degradation process was observed for PS and ABS films.•The macroadditive offers a promising alternative to conventional stabilizers.
Photostabilizer additives are employed to shield polymer materials from ultraviolet (UV) degradation. One category of such additives includes ultraviolet light absorbers (UVA), which absorb radiation and dissipate it within the polymer network as heat. These additives are typically incorporated into the polymer during processing, but they can pose challenges such as low miscibility and migration of the additive to the polymer's surface. A viable solution to these issues is the synthesis of polymers with additives chemically connected to the polymer chain. This work investigates the copolymerization of styrene with the additive 2-3-(2H-benzotriazol-2-yl)-4-hydroxyphenylethyl methacrylate (BHEM), resulting in the formation of PS-BHEM. This copolymer was then utilized in commercial polymers (PS, HIPS, and ABS) to mitigate degradation, with a comparative analysis of its effectiveness against the commercial stabilizer Tinuvin P. The copolymerization process yields a 92 % product, and the presence of BHEM is confirmed through SEC analysis. Accelerated weather degradation tests indicate that the incorporation of PS-BHEM enhances the UV stabilization of commercial ABS without altering the mechanical properties of the polymers.
Visible light has been used therapeutically in dermatology for years for a variety of cosmetic and medical indications, including skin rejuvenation and the treatment of inflammatory and neoplastic ...conditions, among others. Until recently, visible light was thought to be relatively inert compared to its spectral neighbors, ultraviolet and infrared radiation. However, recent literature has described the ability of visible light to cause erythema in light skin and pigmentary changes in individuals with darker skin types. Concern surrounding its potentially damaging cutaneous effects has been raised in both the medical community and social media outlets. In this article, we provide an evidenced-based review describing what is currently known about visible light, focusing on its role in dermatologic diseases including disorders of hyperpigmentation such as melasma and postinflammatory hyperpigmentation.
Although ultraviolet‐C light‐emitting diode (UVC‐LED) has proven antimicrobial effectiveness doses needed to reach it cause adverse effects on the physicochemical quality of fish, and thus, ...optimization studies are crucial to boost its industrial application. This study aimed to identify optimal UVC‐LED conditions for maximum shelf life extension with the least possible quality changes of refrigerated stored tilapia fillets from a central composite rotatable design (CCRD). UVC‐LED powers (1, 1.38, and 1.58 mW/cm2) and times (500, 1800, and 2700 s) were set on the CCRD, which generated 11 treatments, including three replicate experiments. Treatments were analyzed for total aerobic psychrotrophic count, lipid oxidation, instrumental color, and texture parameters on days 0, 2, 4, 7, 11, and 14. The UVC‐LED affected shelf life and physicochemical parameters in a nonlinear fashion. UVC‐LED‐treated fish had increased shelf life by 2.80–4.76 days and increase or decrease in lipid oxidation (0.025–0.276 mg of malondialdehyde MDA/kg), total color change (∆E = 3.47–9.06), and hardness (1.31–8.51 N) over the refrigerated storage depending on specific UVC‐LED conditions applied. The optimal UVC‐LED condition was 0.97 mW/cm2 with 2503.6 s (2428.50 mJ/cm2), which increased the fillet's shelf life by 2.5‐fold (2 days) while maintaining quality closer to the original throughout refrigerated storage, resulting in ∆E < 5, an increase of only 0.05 mg of MDA/kg, and preservation of the decrease in hardness by 3.38 N compared to its control counterparts. Therefore, it represents an eco‐friendly technology that can easily scaled industrially to enhance the sustainable fish production chain.
Practical Application
The high fish perishability is a global concern due to food safety risks and waste generation impacting the environment adversely, especially nowadays, where fish production and consumption have increased, and there are more evident efforts to sustainable production. UVC‐LED is an eco‐friendly technology with proven antimicrobial effectiveness but doses needed to reach this effect enhance oxidative degradation. Despite that, optimization studies concerning the maximum shelf life extension while retaining the physicochemical quality of refrigerated stored fish are a gap in the literature and a barrier to its industrial application. Our findings are helpful in sustainably enhancing the fish production chain.
Background Psoriasis vulgaris is a chronic recurrent inflammatory skin disease and psoriatic lesions have shown leucocyte infiltration.
Objectives We aimed to study C‐reactive protein (CRP) and ...leucocyte activation markers/inhibitors as potential monitors of psoriasis vulgaris.
Methods A cross‐sectional (n = 73) and a longitudinal study (before, at 3, 6 and 12 weeks of therapy; n = 47) was performed; 10 patients started topical treatment, 17 narrow‐band ultraviolet light B (NBUVB) and 20 psolaren associated to UVA (PUVA); psoriasis severity was defined by Psoriasis Area and Severity Index (PASI).
Results Compared with control (n = 38), we found higher CRP levels, total leukocyte/neutrophil count, elastase, lactoferrin and α1‐antitrypsin. Increasing PASI was linked to increasing CRP and a trend to higher elastase and lactoferrin, suggesting that worsening enhances inflammatory response with neutrophil activation. CRP correlated with PASI, total leucocytes, neutrophils, elastase, lactoferrin and α1‐antitrypsin. NBUVB and PUVA presented similar effects.
Conclusion We propose CRP as a useful marker of psoriasis severity that could be used to monitor psoriasis and its treatment, and, together with PASI and elastase, could also be used as a global index of severity.
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•UVA-irradiated FeIII-NTA complex was adopted to activate Oxone at neural pH.•UVA/FeIII-NTA/Oxone process led to a rapid degradation of crotamiton in water.•SO4•− was the dominant ...radical in UVA/FeIII-NTA/Oxone process.•SO4•− preferentially attacked on the amide and methyl groups of the CRMT molecular.
This study demonstrated an efficient activation of Oxone by ultraviolet light A-irradiated FeIII-nitrilotriacetate complex to induce the generation of sulfate and hydroxyl radicals (i.e., SO4•− and HO•) under initial neutral pH. The important parameters such as the solution pH, the molar ratio of nitrilotriacetate:FeIII, the dosages of Oxone and FeIII-nitrilotriacetate complex were evaluated in terms of the degradation kinetics of an emerging contaminant Crotamiton. The results indicated that fast degradation rates of crotamiton were achieved under initial circumneutral conditions (e.g., pH 5.0–7.0), with apparent rate constants at 0.0936–0.1287 min−1 (the ultraviolet light fluence-based rate constants at 0.48–0.66 J−1 cm2). In addition, the optimal molar ratio of nitrilotriacetate:FeIII was determined as 1:1, larger ratios decreased the degradation rate of crotamiton due to the competition effect of nitrilotriacetate on SO4•−. The suitable dosages of Oxone and FeIII-nitrilotriacetate complex were determined as 0.5 mM and 0.1 mM, respectively. Under the given optimal conditions, more than 99% degradation efficiency of crotamiton was achieved at an ultraviolet light fluence of 3.90 J cm−2, better than those results obtained by the activation of S2O82− and H2O2. The results of quenching tests (tert-butyl alcohol and 2-propanol as scavengers) suggested that SO4•− and HO• contributed ~65% and 35% to the degradation of crotamiton, respectively. Furthermore, the identified intermediates includes hydroxy-crotamiton, dihydroxy-crotamiton, aldehyde-crotamiton, aldehyde-dihydroxy-crotamiton, N-ethyl-2,3-dihydroxy-N-(o-tolyl)butanamide, (E)-N-ethyl-N-phenylbut-2-enamide, 2-(ethylamino)benzaldehyde and/or 2-(o-tolylamino)acetaldehyde, and (E)-N-ethylbut-2-enamide. The results indicated that the SO4•− preferentially attacked on the amide and methyl groups of crotamiton. This work provided insight into the efficacy, radicals formation and mechanism on the activation of Oxone by ultraviolet light A-irradiated FeIII-nitrilotriacetate complex, offering an alternative approach for advanced water treatment.
