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Due to photoirradiation-induced deterioration, poly(methyl methacrylate) (PMMA), a thermoplastic that is extensively used and valued for its transparency and adaptability, performs less well in a variety of applications. This extensive analysis looks at creative approaches to improve the photoirradiation stability of PMMA, mostly concentrating on pendant modification techniques. The first sections of the paper explain the importance of stability in PMMA, describe the difficulties caused by photoirradiation, and state the goals of the review. An in-depth analysis of PMMA, including its attributes, traits, and many uses, prepares the reader for the investigation of stability improvement methods that follow. The literature review section explores previous research on PMMA stability, pointing out knowledge gaps and areas needing more research. After that, the focus turns to pendant customization and offers a thorough explanation, illustrations, and change procedures. An extensive analysis is conducted on many pendant modification methods, such as photostabilizing nanoparticles, hindered amine light stabilizers, and grafting of benzotriazole derivatives. Comparative evaluations draw attention to the advantages and disadvantages of each method. Optical devices, automotive components, and architectural glazing are identified as domains in which modified PMMA exhibits exceptional performance. [ABSTRACT FROM AUTHOR]

Poly (vinyl chloride) (PVC) films modified with ethylenediamine (en) and doped by nanoparticles (TiO2, ZnO, NiO, and MgO). A mixture of 0.5 g PVC/en dissolved in THF and 0.01 wt % of nanoparticles were used in doping PVC to produce the nanocomposite films. All modified PVC films were characterized by different analysis techniques such as Fourier Transform Infrared (FTIR), Nuclear Magnetic Resonance Spectrometer (NMR), diffusive reflectance spectroscopy (DRS), X‐ray diffraction analysis (XRD), and scanning electron microscopy (SEM). The DRS was used to analyse the scattered IR energy of the samples at wavelengths between (250–1350 nm). The optical properties and oscillator strength were also studied, the transmittance and reflectance values declined for the PVC films, and the absorption coefficient was observed between (79–89 %). The direct energy gap decreased from 4.6 to 1.9, and the indirect energy gap reduced from 4.3 to 1.9. The XRD exhibited a semi‐crystalline structure and the SEM test exhibited a porous structure of all samples. The Urbach energy was increased from 0.8772 eV to 14.712 eV, single oscillator energy (Eo ${{E}_{o}}$) was also increased from 6.38 eV to 13.69 eV and the dispersion energy (Ed) ${{(E}_{d})}$ increased from 23.40 eV to 70.63 eV. Moreover, the surface roughness parameters Ra and Rq of the PVC films in modified and doping were increased from 3.86 nm to 8.14 nm, and 5.08 nm to 10.10 nm respectively. So, PVC results show increased optical properties after modification with en and doping by NPs are used in the light conversion and aerospace industries. [ABSTRACT FROM AUTHOR]

Poly(vinyl chloride) (PVC) films were synthesized by incorporating organic groups, specifically amino groups derived from ethylene di-amine (en). The casting process was employed, with tetrahydrofuran (THF) utilized as the solvent. The incorporation of 4 metal oxide nanoparticles (NPs), namely MgO, ZnO, NiO and TiO2, was carried out to enhance the stability of the films during light exposure. The effect of UV radiation dose was significant. Subsequent exposure of the PVC films to ultraviolet light enabled the evaluation of resulting damage through various analytical and morphological techniques. The utilization of infrared spectroscopy and weight loss study suggested that the films incorporating additives exhibited less harm and little alterations on the surface, as compared to the unaltered film. Among the modified films, the PVC-en/TiO2 NPs film exhibited the highest resistance against the photodegradation process, as evidenced by the data derived from FTIR spectra, weight loss measurements, and surface morphology analyses. Titanium dioxide nanoparticles have been good PVC photostabilizer because of its capacity to block ultraviolet (UV) radiation. The atomic force microscopy (AFM) photographs of the PVC-en/TiO2 NPs film after irradiation revealed a smooth surface, exhibiting a roughness factor (Rq) of 34.3, in contrast to the PVC (blank) which had a roughness factor of 282.2. SEM images for irradiated PVC films reveal the existence of cracks, cavities, protrusions, blemishes and formless, uneven surfaces. Microscopic images revealed that the surface of untreated PVC films exhibited significantly more pronounced damage and anomalies following irradiation compared to modified PVC films incorporating nano-metal oxides. [ABSTRACT FROM AUTHOR]

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Exposure to ultraviolet radiation triggers a photooxidative deterioration mechanism in plastics, resulting in bond breakage, release of volatile substances, overall weight reduction, generation of free radicals, and loose crosslinking. The aim of this study was to obtain a plant extract with appropriate concentration and use it to protect polyvinyl chloride (PVC) from photodegradation. PVC films containing different concentrations of naringin that were already extracted and TINUVIN 622 as a commercial stabilizer were investigated in this paper. UV light was used to irradiate PVC films for 300 h to test the photostability. After radiation, infrared spectra, weight loss, molecular weight reduction, and surface morphology examination for PVC films were studied. In comparison to blank film, the photodegradation of PVC films was significantly reduced by the naringin and TINUVIN 622 photostabilizers. The role of photostabilizers includes deactivating excited states (as quenchers), functioning as effective light filters (pigments and absorbers), scavenging radicals, and decomposing hydroperoxides. [ABSTRACT FROM AUTHOR]

Gas storage is an important branch of technology that has many economic and environmental aspects. This technique could save gas to the need time and contribute to solving the CO2 and global warming problems. In this work, the structure and physicochemical properties of the prepared palladium complex were characterized in the solid and solution states using spectroscopic techniques. These examination methods include ultraviolet-visible (UV-Vis), Fourier transform infrared (FTIR), metal and elemental analyses, and measurements of magnetic susceptibility and conductivity at room temperature. Also, findings on the surface morphology and surface area were provided via Field emission scanning electron microscopy (FESEM) and Brunauer-Emmett- Teller (BET) techniques, respectively. High-pressure adsorption measurements were investigated by storing carbon dioxide, and the results proved that such materials own remarkable gas adsorption properties that make them a good option for gas separation and storage. Gases uptake at 323 K for the complexes leads to the highest CO2 uptake. The prepared material could pave the road for further exploitation of similar materials. [ABSTRACT FROM AUTHOR]

Films of polyvinyl chloride with oxide nanoparticles (MgO, NiO, TiO2, and ZnO) and clarithromycin were prepared. Oxide nanoparticles were used in low concentrations (0.01% by weight) along with clarithromycin. The analysis of oxide nanoparticles and clarithromycin as UV blockers for PVC photodegradation investigations into weight loss, surface morphology, and IR changes, revealed that titanium oxide, especially, protects PVC from harmful ultraviolet light. [ABSTRACT FROM AUTHOR]

A new traiazole derivative (4-amino-5-(((5-methyl-1H-benzo[d]imidazol-2-yl)thio)methyl)-2,4-dihydro-3H-1,2,4-triazole-3-thiol, (L), was employed as a chelating ligand to form a dibutyltin chloride complex and improve the poly(vinyl chloride) (PVC) properties. The doped PVC films were characterized via FT-IR, UV-Vis spectrum, elemental analyses (C, H, N, and M (metallic)), and magnetic susceptibility and conductivity measurements. These characterizations were conducted at room temperature, and it was disclosed that the chelating ligand rules as a bidentate chelate. The photostabilization examination of plain and L-doped PVC films was conducted in the presence of ambient air using the accelerating weather tester, where the doping ratio was fixed to 0.5 wt.%. The photostabilization performance of the additive was evaluated by tracking the indexes of carbonyl (ICO), polyene (IPO), and hydroxyl (IOH), and weight loss relationship with irradiation time. It was noticed that the values of ICO, Ipo, and IOH increased as the irradiation time increased, where this improvement relied on the presence of the Bu2SnL complex. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 virus (COVID-19), the cause of coronavirus disease, has several variations. Some are thought to be particularly important or have been said to be so, because of their potential for greater transmissibility, Virus pathogenicity has grown, or vaccinations against them have become less effective. These mutations have a role in the COVID-19 pandemic's persistence. The B.1.1.529-Omicron variant, found in many coronavirus cases reported in South Africa discovered late 2021, having a surprisingly great number of mutations which raise a concern toward the spreadablity of this variant and severity of illness in comparison to other corona virus variants as well as the effectivity of the available vaccinations. This review summarizes of the most recent information and the answers to most of the world's questions about Omicron. [ABSTRACT FROM AUTHOR]

This review highlighted the analysis techniques of hydroxamic acid (HAs) and Organotin (IV) Hydroxamates. Different isomerism, keto and enol form, as well as, intra and inter hydrogen bonding are confirmed through spectroscopic studies. In addition all organotin (IV) complexes geometries were studied and explained in this review depending on different analysis techniques done by researchers. Our study is not unique but it gives your attention to be more concern if you will deal with these types of compounds regarding to the functional groups, isomerism, structural information and its geometry. [ABSTRACT FROM AUTHOR]

No hay vida sin libertad—"There is no life without freedom"—read a sign at a rally demanding the closure of the T. Don Hutto Residential Center in Taylor, Texas, in November 2015. The rally was held in support of 27 women imprisoned in the detention center who had launched an indefinite hunger strike. Fleeing state and intimate partner violence and persecution in their home countries, the women detained in the Hutto detention center were driven to strike after suffering months of abysmal living conditions and inhumane treatment at the hands of U.S. Immigration and Customs Enforcement (ICE). In this article, I analyze 11 letters composed by some of the #Hutto27 detainees. Conceptualizing the letters as testimonios that serve as powerful testaments to trauma, anguish, and, ultimately, solidarity through defiance, I argue that the letters construct a feminist archive of resistance—one which allows a glimpse into the affective life of detention. [ABSTRACT FROM AUTHOR]

A study was performed on 60persons31 of them are hypertensive their age ranged between (46-75) and 29 subjects as control (non hypertensive) with age ranged between (40-73) years were investigated to assess the correlation between salivary fibronectin and serum fibronectin in both hypertensive patients and control. The results shows that the level of salivary fibronectin was significantly (P ≤ 0.05) higher in hypertensive patients (40.19± 7.122 ng/ml) compared to control (22.827 ± 5.414ng/ml). Mean of serum fibronectinis significantly (P ≤ 0.05) higher in hypertensive patients (70.965±14.99 ng/ml) compared to control (60.068±13.6 ng/ml).A correlation study showed that salivary fibronectin was positively correlated with serum fibronectin in both hypertensive patients and controls(P ≤ 0.05). We can conclude that salivary fibronectin represent serum fibronectin because they positively correlated in both hypertensive patients group and control. [ABSTRACT FROM AUTHOR]