UV-digital printing belongs to the commonly used method for custom large-area substrate decoration. Despite low surface energy and adhesion, transparent polymer materials, such as polymethylmethacrylate (PMMA) and polycarbonate (PC), represent an ideal substrate for such purposes. The diffuse coplanar surface barrier discharge (DCSBD) in a novel compact configuration was used for substrate activation to improve ink adhesion to the polymer surface. This industrially applicable version of DCSBD was prepared, tested, and successfully implemented for the UV-digital printing process. Furthermore, wettability and surface free energy measurement, X-ray photoelectron spectroscopy, atomic force and scanning electron microscopy evaluated the surface chemistry and morphology changes. The changes in adhesion of the surface and of ink were analyzed by a peel-force and a crosscut test, respectively. A short plasma treatment (1-5 s) enhanced the substrate's properties of PMMA and PC while providing the pre-treatment suitable for further in-line UV-digital printing. Furthermore, we did not observe damage or significant change of roughness affecting the substrate's initial transparency.

The leaves of Ligustrum robustum have been applied as Ku-Ding-Cha, a functional tea to clear heat and remove toxins; and served as a folk medicine to deal with diabetes, obesity, and hypertension. Trans-p-hydroxycinnamic acid and its esters, which were isolated from the leaves of L. robustum, might be a new resource to prevent diabetes and its complications because of their strong -glucosidase and fatty acid synthase (FAS) inhibitory activities and antioxidant effect. However, the quantitative analytical method for trans-p-hydroxycinnamic acid and its esters in the leaves of L. robustum hasn’t been reported so far. In addition, it was difficult and troublesome to analyze no less than 34 trans-p-hydroxycinnamic acid esters by usual HPLC. Therefore, a new HPLC-UV method using hydrolyzation with sodium hydroxide for quantitation of trans-p-hydroxycinnamic acid and its esters in the leaves of L. robustum was developed in the present study. The optimal hydrolyzation conditions were as follows: 1 mL sodium hydroxide aqueous solution (1 M) was added into 1 mL the extract of L. robustum and incubated at 80 °C for 2 h , and then 1 mL hydrochloride (1 M) solution was added. HPLC analysis was performed in reverse phase mode using a C-18 column, eluting with methanol-0.1% acetic acid aqueous solution (40:60, v/v) in isocratic mode at a flow rate of 1.0 mL/min, and detecting at 310 nm. The analytical method was simple and rapid, which simplified greatly the analytical process. The method was validated in terms of linearity, limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy. High linearity was demonstrated with correlation coefficient of 1.000 for trans-p-hydroxycinnamic acid. The LOD and LOQ values were 1.55 and 4.69 μg/mL, respectively. The relative standard deviations (RSD) of intra-day and inter-day variabilities for trans-p-hydroxycinnamic acid were less than 2%. The percentage recovery of trans-p-hydroxycinnamic acid was 101.2% ± 0.8%. Finally, the proposed method was applied successfully to the determination and comparison of the contents of trans-p-hydroxycinnamic acid and its esters in various extracts of the leaves of L. robustum. The 60%-70% ethanol extracts of L. robustum showed the highest contents of free trans-p-hydroxycinnamic acid (3.96-3.99 mg/g), and the 50%-80% ethanol extracts of L. robustum displayed the highest contents of trans-p-hydroxycinnamic acid esters (202.6-210.6 mg/g). The method can be applied also to the quality control of the products of L. robustum.

Modification the biodegradable matrix was carried by graft-copolymerization polylactide with methacrylic acid of various concentrations. Ultraviolet irradiation with different exposure times to the samples was chosen as the initiator of copolymerization. In the experiment the effect of ultraviolet light on polylactide and graft copolymerization was investigated: the resulting samples were studied by viscosimetry, gravimetry, FTIR, static cation- exchange capacity analysis . The conditions for obtaining grafted copolymers and the dependence of the characteristics on the reaction conditions are established.

The purpose of water treatment through ultraviolet (UV) radiation is to interrupt the development and multiplication of microorganisms by preventing their growth and reproduction.Ultraviolet treatment has become a very affordable solution to produce clean water of optimal quality in regions where access to drinking water is essential. The experimental water treatment unit is powered by a photovoltaic (PV) source. It incorporates a discharge lamp used to generate ultraviolet radiation, which is harnessed to address bacteriological issues related to water quality. This lamp is continuously powered by a photovoltaic (PV) source through an inverter and an electronic ballast. The water treatment system also includes a motor pump designed to draw contaminated water from the input reservoir, a flow control valve to adjust flow rates as needed, and a filter aimed at enhancing the quality of the contaminated water. The water circulates between the input reservoir (contaminated water) and the output reservoir (treated water) through the UV lamp. The relationship between the intensity of the UV lamp and the water flow rate can ensure an adequate water quality.

As the global semiconductor market is growing steadily, the need for optimization of the man-ufacturing process is paramount. For example, in the process of transferring the semiconductor chips to the substrate, each chip needs to be individually separated from the dicing tape via a plunger. In this process, however, the fixed chip is not easily removed from the tape due to strong adhesion, and the chip can become damaged if it is forcibly pulled out. Therefore, the present paper reports the development of functional adhesive tapes that initially adhere strongly to the semi-conductor chip on the dicing tape but can be easily removed after transfer. The fabricated functional tape has an initial adhesion of 350 gf, which enables firm fixing of the semiconductor chip to be transferred, and a final adhesion of 0.8 gf after UV curing, thereby facilitating removal of the chip without damage after transfer. Therefore, the fabricated functional tape is expected to contribute to the optimization of the semiconductor manufacturing process and is expected to be useful in the semiconductor package manufacturing process.

Highly transparent, conductive nanosheets are extremely attractive for advanced optoelectronic applications. Previously, we have demonstrated that transparent, conductive Au nanosheets can be prepared by UV irradiation of Au nanoparticle (AuNP) monolayers spread on water, which serves as the subphase. In this study, we show that this UV irradiation technique can easily be extended as a nanosheet modification method by using subphases containing metal ions. That is, aqueous solutions containing Au and Ag ions are effective in modifying Au nanosheets. HAuCl4 solutions increased Au nanosheet thickness, which improved conductivity, but reduced transparency. On the other hand, use of aqueous AgNO3 and CH3COOAg solutions yielded Au-Ag hybrid nanosheets; however, their morphologies depended on the electrolytes used. Homogeneous Au-Ag nanosheets from AgNO3 and AuNPs covered with an Ag nanosheet from CH3COOAg were also produced. Further, these Au-Ag hybrid nanosheets had high conductivity without reduced transparency. Therefore, this UV irradiation method, modified by adding metal ions is quite effective at improving and diversifying properties of Au nanosheets.

The manuscript presents the optical properties of directly deposited films of gold nanoparticles (AuNPs) prepared by ultrasonic spray pyrolysis technology. Four samples were produced, with an AuNPs deposition time of 15 min, 30 min, 1h and 4h on the glass substrate. The morphological characterization of the deposited films showed that the size of the first deposited AuNPs is between 10 and 20 nm, while with a longer duration of the deposition process, larger clusters of AuNPs grow by coalescence and aggregation. The prepared layers were optically characterised with Ultraviolet–visible spectroscopy (UV-vis) and ellipsometry. The ellipsometric measurements showed an increasingly denser and thicker effective thickness of the AuNPs layers. The extinction spectra display a clear local surface plasmonic resonance (LSPR) signature (peak 520-540 nm), indicating the presence of isolated particles in all samples. For all AuNPs layers, the imaginary part of both ε// and ε⏊ is dominated by a central peak around 2.2 eV corresponding to the LSPR of isolated particles and a high-energy shoulder due to Au interband transitions. It is shown that, as the density of particles increases, the extinction cross section grows over the whole spectral range where measurements are taken. Thus response can be explained with an enhanced electromagnetic response among AuNPs, that can be connected to the increase of particle density but also by the formation of clusters and irregular structures.

Copper(II), nickel(II) and zinc(II) complexes of various peptide fragments of tau protein were studied by potentiometric and spectroscopic techniques. All peptides contained one histidyl residue and represented the sequences of tau(91-97) (Ac-AQPHTEI-NH2), tau(385-390) (Ac-KTDHGA-NH2) and tau(404-409) (Ac-SPRHLS-NH2). Imidazole-N donors of histidine were the primary metal binding sites for all peptides and all metal ions but in case of copper(II) and nickel(II) the deprotonated amide groups were also involved in metal binding by increasing pH. The most stable complexes were formed with copper(II) ion but the presence of prolyl residues resulted in significant changes in the thermodynamic stability and speciation of the systems. It was also demonstrated that nickel(II) and especially zinc(II) complexes have relative low thermodynamic stability with these peptides. Copper(II) catalyzed oxidation of the peptides was also studied. In the presence of H2O2 the fragmentation of peptides can be detected in all cases. In the simultaneous presence of of H2O2 and ascorbic acid the extent of the fragmentation of the peptide is less preferred, and the formation of 2-oxo-histidine also occurs.

In the present research, groups of nanolayered structures and nanohybrids based on organic green dyes and inorganic species are designated to act as fillers for PVA for inducing new optical sites and increasing its thermal stability through producing polymeric nanocomposites. In this trend, different percentages of Naphthol green B were intercalated as pillars inside the Zn-Al nanolayered structures to form green organic-inorganic nanohybrids. The two-dimensional green nanohybrids were identified by X-ray diffraction, TEM and SEM. According to the thermal analyses, the nanohybrid, which has the highest amount of green dyes, was used for modifying the PVA through two series. In the first series, three nanocomposites were prepared depending on the green nanohybrid as prepared. In the second series, the yellow nanohybrid, which was produced from the green nanohybrid by thermal treatment, was used to produce another three nanocomposites. The optical properties revealed that the polymeric nanocomposites depending on green nanohybrids became optical-active in UV and visible regions because the energy band gap decreased to be 2.2 eV. In addition, the energy band gap of the nanocomposites depended on yellow nanohybrids was 2.5 eV. The thermal analyses indicated that the polymeric nanocomposites are thermally more stable than that of the original PVA. Finally, the dual functionality of organic-inorganic nanohybrids that produced from the confinement of organic dyes and the thermal stability of inorganic species converted the non-optical PVA to optical-active polymer in a wide range with high thermal stability

Sunscreens are topical preparations containing one or more compounds that protect humans from ultraviolet (UV) light. This review focuses on analytical methods, particularly liquid chromatography, aimed at identifying and determining UV filters (UVFs) in environmental and marine biota matrices. A literature review was done using NIH (PubMed and Medline), FDA and EPA databases, Google Scholar, and Federal Regulations. This retrospective literature review is focused on the last five years. UVFs quantification in environmental and biological matrices showed a wide array of methods where liquid chromatography is predominant. The scientific literature identified a large variety of analytical methodologies that are compared in this review, to evaluate the better results in terms of limits of quantification and the possibility to identify as many analytes as possible simultaneously.

Abstract: Peptide pools composed of short amino acid sequences have proven to be versatile tools in various research areas and clinical applications. They are powerful tools for epitope mapping, immunotherapy, and vaccine development. Their importance lies in their ability to map complex protein structures, enabling a comprehensive understanding of immune responses and facilitating the identification of potential therapeutic agents. The application of peptide pools also extends to the field of personalized medicine, offering tailored solutions for diseases such as cancer and infectious diseases. Peptide pools are complex mixtures of immunostimulatory antigens primarily intended for T-cell stimulation. They are commercially available in many different compositions and variants. However, unlike other reagents that consist of only one or a few compounds, peptide pools are highly complex products with limited stability. This makes their quality control a major challenge. Quantitative peptide analysis usually requires sophisticated methods, in most cases isotope-labeled standards and reference materials. None of these are routinely available for these products. Synthesis and purification of all labeled peptides might be required. Usually, this approach would be prohibitively laborious and expensive. Therefore, an approach is needed to provide a practical and feasible method for quality control of peptide pools. With insufficient quality control, the use of such products could lead to incorrect experimental results, which would worsen the well-known reproducibility crisis in the biomedical sciences. Here we propose the use of ultra-high performance liquid chromatography (UHPLC) with two detectors, a standard UV detector (at 214 nm) for quantitative analysis and a high-resolution mass spectrometer (HRMS) for identity confirmation. To be cost-efficient and fast, quantification and identification are performed in one chromatographic run. An optimized protocol is shown, and different peak integration methods are compared and discussed. This work was performed using a peptide pool known as CEF, which consists of 32 peptides derived from cytomegalovirus (CMV), Epstein-Barr virus (EBV) and influenza virus, ranging from 8 to 12 amino acids in length.

Petrosamine (1) – a colored pyridoacridine alkaloid from the Belizean sponge, Petrosia sp. that is also a potent inhibitor of acetylcholine esterase (AChE) – was investigated by spectroscopic and computational methods. Analysis of the petrosamine free energy landscapes, pKa and tautomerism revealed an accurate electronic depiction of the molecular structure of 1 as the di-keto form, with net charge of q = +1, rather than a dication (q = +2) under ambient conditions of isolation-purification. The pronounced solvatochromism (UV-vis) reported for 1, and related analogs, was investigated in detail and is best explained by charge delocalization and stabilization of the ground state (HOMO) of 1 rather than an equilibrium of competing tautomers. Refinement of the molecular structure of 1 by QM methods complements published computational docking studies to define the contact points in the enzyme active site that may improve design of new AChE inhibitors based on the pyridoacridine alkaloid molecular skeleton.

To improve efficacy and safety of sunscreen emulsions, UV‐filter skin permeation could be kept as low as possible by reducing UV‐filter content or changing emulsion composition. In this work, different lipid phase ratio (12, 14 and 16% w/w) were assessed for their ability to affect the technological and sensory properties of O/W emulsions in which bemotrizinol (BMTZ), a broad spectrum sunscreen agent, was incorporated free or loaded into nanostructured lipid nanocarriers (NLC) to reduce its release from the vehicle and, hence, its skin permeation. The following technological properties were evaluated in vitro by suitable methodologies: spreadability, viscosity, pH, occlusion factor, BMTZ release, sun protection factor (SPF). Sensory attributes were assessed by trained panelists in three different phases: before/during pick‐up, rub‐in, after application. Raising the lipid phase ratio led to an increase of viscosity and to a corresponding drop of spreadability while the incorporation of BMTZ‐loaded NLC determined a decrease of occlusion factor and an increase of SPF. No BMTZ release was observed from all emulsions. Sensory attributes were mainly affected by lipid phase ratio. These results suggest that lipid phase ratio and BMTZ incorporation into NLC could contribute to determine technological and sensory properties of O/W emulsions.

The development of photocurable compositions is in high demand for the manufacture of func-tional materials for electronics, optics, medicine, energy, etc. The properties of the final pho-to-cured material are primarily determined by the initial mixture, which needs to be tuned for each application. In this study we propose to use simple systems based on di(meth)acrylate, polyimide and photoinitiator for the preparation of new photo-curable compositions. It was es-tablished that a fluorinated cardo copolymide (FCPI) based on 2,2-bis-(3,4-dicarboxydiphenyl)hexafluoropropane dianhydride, 9,9-bis-(4-aminophenyl)fluorene and 2,2-bis-(4-aminophenyl)hexafluoropropane (1.00:0.75:0.25 mol) has excellent solubility in di(met)acrylates. This made it possible to prepare solutions of FCPI in such monomers, to study the effect of FCPI on the kinetics of their photopolymerization in situ and the properties of the resulting polymers. According to the obtained data, the solutions of FCPI (23 wt.%) in 1,4-butanediol diacrylate (BDDA) and FCPI (15 wt.%) in tetraethylene glycol diacrylate were tested for the formation of the primary protective coatings of the silica optical fibers. It was found that the new coating of poly(BDDA–FCPI23%) can withstand prolonged annealing at 200°C (72 h), which is comparable or superior to the known most thermally stable photo-curable coatings. The proposed approach can be applied to obtain other functional materials.

The photodegradation of azithromycin present was carried out in water using H2O2 under UV irradiation. The reaction variables considered in this study were the amount of H2O2 solution and the initial concentration of azithromycin to evaluate the performance of the photodegradation process. The azithromycin degradation was not observed in the dark during stirring for 20 minutes. The study showed efficient photodegradation of azithromycin using H2O2 as an oxidant in the presence of UV irradiation. The azithromycin degradation was affected significantly by the pH of the irradiated solution. The degradation was low at an acidic pH and showed an increasing trend as the pH changed to basic. The azithromycin degradation was increased with a higher amount (higher concentration) of H2O2. The degradation of azithromycin decreased with a higher concentration of azithromycin in the reacting solution. The highest degradation of AZT was achieved in 1 hour using a 1.0 ppm AZT solution containing 3 ml of H2O2. The experimental data obtained was well-fitted to zero-order reaction kinetics. The results of this study were found to be superior when compared with those reported in the literature, with photocatalysis using nanomaterials and photolysis using irradiation and H2O2. The UV/H2O2 system was found to be quite efficient for the photodegradation of azithromycin, and this system can be applied to degrade other organic pollutants present in industrial wastewater. To this point, such a study has not been reported specifically for AZT photodegradation.