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The title compound was synthesized and structurally characterized. Theoretical IR, NMR (with the GIAO technique), UV, and nonlinear optical properties (NLO) in four different solvents were calculated for the compound. The calculated HOMO–LUMO energies using time-dependent (TD) DFT revealed that charge transfer occurs within the molecule, and probable transitions in the four solvents were identified. The in silico absorption, distribution, metabolism, and excretion (ADME) analysis was performed in order to determine some physicochemical, lipophilicity, water solubility, pharmacokinetics, drug-likeness, and medicinal properties of the molecule. Finally, molecular docking calculation was performed, and the results were evaluated in detail.

Various polyvinyl chloride thin films containing captopril and several metal (cobalt, copper, and nickel) oxide nanoparticles were produced. Low concentrations of both captopril (0.5% by weight) and metal oxides (0.01% by weight) were used to produce transparent films. The role played by both captopril and metal oxide nanoparticles as ultraviolet blockers for photodegradation of polyvinyl chloride was investigated. The addition of both metal oxides and captopril to polyvinyl chloride films enhances the stability of polymeric materials more than captopril alone. Observation of weight loss, changes in infrared spectra and surface morphology of blends on irradiation showed that a combination of captopril and nickel oxide nanoparticles efficiently blocks ultraviolet light and provides a high level of protection to polyvinyl chloride.

Purpose. Smoking has a negative effect on health and ocular tear film. The purpose of the current study is to investigate the correlation between the TearLab and I-Pen osmolarity scores in smokers and compare them with those of non-smoking healthy males. Methods. Thirty male smokers (25.3 ± 2.2 years) participated in the study. An age-matched (22.9 ± 2.0 years) control group of non-smoking healthy males (N = 30) was also recruited for comparison purposes. The ocular surface disease index (OSDI) was completed first, followed by the TearLab and I-Pen osmolarity measurements. Results. The median TearLab osmolarity score was lower (P < 0.001) than that obtained using the I-Pen in both the study and the control groups. The OSDI scores and osmolality measurements were higher (P < 0.001) in smokers than in the control subjects. In the smoker group, there were moderate correlations between the OSDI scores and the measurements obtained using the TearLab (Spearman’s correlation coefficient, r = 0.463; P = 0.010) and I-Pen (r = 0.449; P = 0.013) systems. In addition, there was a strong correlation between the osmolarity scores obtained from the TearLab and I-Pen systems in smokers (r = 0.911; P < 0.001). Conclusion. The I-Pen scores in smokers were significantly higher than those obtained using TearLab. The TearLab scores showed small variations compared with those obtained using I-Pen. A strong correlation was found between the TearLab and I-Pen scores in smokers. The osmolarity TearLab and I-Pen scores were significantly higher in smokers compared with normal eye subjects.

Curcumin can be isolated from plants (Curcuma longa) and it belongs to the ginger family. It exhibits many useful properties and acts as an antioxidant. The aim of the current study was to prepare eight curcumin analogues and investigate their antioxidant activities to inhibit the thermal degradation of low-density polyethylene (LDPE). The carbonyl index (CI) was measured to test the effectiveness of the curcumin analogues. Various doses (0.5, 1, 2, 4, and 6% wt/wt) of a mixture containing LDPE and curcumin analogues were prepared, and the CI was measured. The eight curcumin analogues were found to have good to excellent antioxidant activity against the degradation of LDPE. It was clear that the curcumin analogue derived from vanillin and acetone has the highest antioxidant activity. The density functional theory study was conducted for the eight curcumin analogues to test their reactivity and stability. Again, the global reactivity descriptors analysis showed that compound derived from vanillin and acetone was the most reactive compound to inhibit thermal degradation of LDPE.

As poly(vinyl chloride) (PVC) photodegrades with long-term exposure to ultraviolet radiation, it is desirable to develop methods that enhance the photostability of PVC. In this study, new aromatic-rich diorganotin(IV) complexes were tested as photostabilizers in PVC films. The diorganotin(IV) complexes were synthesized in 79–86% yields by reacting excess naproxen with tin(IV) chlorides. PVC films containing 0.5 wt % diorganotin(IV) complexes were irradiated with ultraviolet light for up to 300 h, and changes within the films were monitored using the weight loss and the formation of specific functional groups (hydroxyl, carbonyl, and polyene). In addition, changes in the surface morphologies of the films were investigated. The diorganotin(IV) complexes enhanced the photostability of PVC, as the weight loss and surface roughness were much lower in the films with additives than in the blank film. Notably, the dimethyltin(IV) complex was the most efficient photostabilizer. The polymeric film containing this complex exhibited a morphology of regularly distributed hexagonal pores, with a honeycomb-like structure—possibly due to cross-linking and interactions between the additive and the polymeric chains. Various mechanisms, including direct absorption of ultraviolet irradiation, radical or hydrogen chloride scavenging, and polymer chain coordination, could explain how the diorganotin(IV) complexes stabilize PVC against photodegradation.

Three polyphosphates were used as inhibitors for poly(vinyl chloride) (PVC) photodegradation. The polyphosphates were added to PVC at a concentration of 0.5% by weight. The PVC films (40 µm thickness) were irradiated at room temperature with ultraviolet (UV) light for up to 300 h. The changes in PVC films after irradiation were monitored by Fourier transform infrared spectroscopy, weight loss, viscosity-average molecular weight determination, and atomic force microscopy. These changes were very noticeable in the blank PVC films compared to the ones obtained when additives were used. The polyphosphates can inhibit the PVC photodegradation through direct absorption of UV light, interactions with PVC chains, and acting as radical scavengers.

Ceramic materials based on mullite, cristobalite, and zircon phases prepared with different zinc and copper additions using the co-precipitation method and followed by calcination at 500 °C for 2 h are investigated. The effectiveness of these substrates against bacteria was tested against Gram-positive and Gram-negative pathogenic strains: Staphylococcus aureus , Bacillus subtilus , Escherichia coli , Pseudomonas putida, and Enterobacter aerogenes . The obtained nanoparticles with different crystal sizes were subjected to various types of characterization, including structural by X-ray diffraction (XRD), morphology by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) transmission electron microscopy (TEM), optical analysis by Raman spectroscopy. SEM images showed a change in the shape of the ceramic nanocomposites after adding zinc and copper to become similar to flake structures. This addition was detected by EDS analysis, where the first sample was found to contain 1.49 at.% Cu and 7.41 at.% Zn. The TEM image confirmed that the kaolin grains were in the form of nanotubes and were coated with spherical nanograins after adding ZrO 2 , Zn, and Cu. The newly developed ceramic compound, consisting of mullite–zircon–zinc oxide–copper oxide with a primary source, kaolin DD3, was found to be more effective than its predecessors. It gave unprecedented anti-activity for many types of bacteria (Gram-positive and Gram-negative). Given the shape flake-like of the new ceramic compound, it provides a wider effective area through micro-tubes to the granules. It has a high percentage of holes that allow bacteria to be attracted and placed inside. A maximum inhibition zone of 38.1 ± 0.1 mm was obtained with S. aureus for DD3 + ZrO 2 /ZnO (28 wt.%)/CuO (2.8 wt.%), a zone of 29.2 ± 0.2 mm with P. putida ; for DD3 + ZrO 2 /ZnO (14.28 wt.%)/CuO (5.37 wt.%) and an inhibition zone of 28.85 ± 0.15 mm was obtained with B. subtilis for DD3 + ZrO 2 /ZnO (14.28 wt.%)/CuO (5.37 wt.%). The ceramic DD3 + 38% ZrO 2 possesses 33% of the holes, which represents the largest percentage in this compound and, therefore, is primarily responsible for the effect that occurs during biological application. All samples showed a high antibacterial activity, which increased with the addition of Zn:Cu and decreased with the increase in grain size. Ions and reactive oxygen species (ROS) release released into the cellular environment present a huge obstacle to dynamic membrane transport and lead to DNA damage and, ultimately, cell necrosis or apoptosis, which was effective for the inhibition of bacterial growth.

Poly(vinyl chloride) (PVC), a polymer widely used in common household and industrial materials, undergoes photodegradation upon ultraviolet irradiation, leading to undesirable physicochemical properties and a reduced lifetime. In this study, four telmisartan organotin(IV) compounds were tested as photostabilizers against photodegradation. PVC films (40-µm thickness) containing these compounds (0.5 wt%) were irradiated with ultraviolet light at room temperature for up to 300 h. Changes in various polymeric parameters, including the growth of hydroxyl, carbonyl, and alkene functional groups, weight loss, reduction in molecular weight, and appearance of surface irregularities, were investigated to test the efficiency of the photostabilizers. The changes were more noticeable in the blank PVC film than in the films containing the telmisartan organotin(IV) compounds. These results reflect that these compounds effectively inhibit the photodegradation of PVC, possibly by acting as hydrogen chloride and radical scavengers, peroxide decomposers, and primary photostabilizers. The synthesized organotin(IV) complexes could be used as PVC additives to enhance photostability.

Five Schiff bases derived from melamine have been used as efficient additives to reduce the process of photodegradation of poly(vinyl chloride) films. The performance of Schiff bases has been investigated using various techniques. Poly(vinyl chloride) films containing Schiff bases were irradiated with ultraviolet light and any changes in their infrared spectra, weight, and the viscosity of their average molecular weight were investigated. In addition, the surface morphology of the films was inspected using a light microscope, atomic force microscopy, and a scanning electron micrograph. The additives enhanced the films resistance against irradiation and the polymeric surface was much smoother in the presence of the Schiff bases compared with the blank film. Schiff bases containing an ortho-hydroxyl group on the aryl rings showed the greatest photostabilization effect, which may possibly have been due to the direct absorption of ultraviolet light. This phenomenon seems to involve the transfer of a proton as well as several intersystem crossing processes.

Three organotin complexes containing furosemide as a ligand (L), Ph3SnL, Me2SnL2 and Bu2SnL2, were synthesized and characterized. Octahedral geometry was proposed for the Me2SnL2 and Bu2SnL2, while the Ph3SnL complex has trigonal bipyramid geometry. The synthesized organotin complexes (0.5% by weight) were used as additives to improve the photostability of poly(vinyl chloride), PVC, (40 μm thickness) upon irradiation. The changes imposed on functional groups, weight loss and viscosity average molecular weight of PVC films were monitored. The experimental results show that the rate of photodegradation was reduced in the presence of the organotin additives. The quantum yield of the chain scission was found to be low (9.8 × 10−7) when Ph3SnL was used as a PVC photostabilizer compared to controlled PVC (5.18 × 10−6). In addition, the atomic force microscope images for the PVC films containing Ph3SnL2 after irradiation shows a smooth surface compared to the controlled films. The rate of PVC photostabilization was found to be highest for Ph3SnL followed by Bu2SnL2 and Me2SnL2. It has been suggested that the organotin complexes could act as hydrogen chloride scavengers, ultraviolet absorbers, peroxide decomposers and/or radical scavengers.