Total Electron Detachment and Induced Cationic Fragmentation Cross Sections for Superoxide Anion (O2−) Collisions with Benzene (C6H6) Molecules

In this study, novel experimental total electron detachment cross sections for O₂⁻ collisions with benzene molecules are reported for the impact energy range (10–1000 eV), as measured with a transmission beam apparatus. By analysing the positively charged species produced during the collision events, relative total ionisation cross sections were derived in the incident energy range of 160–900 eV. Relative partial ionisation cross sections for fragments with m/z ≤ 78 u were also given in this energy range. We also confirmed that heavier compounds (m/z > 78 u) formed for impact energies between 550 and 800 eV. In order to further our knowledge about the collision dynamics governing the fragmentation of such heavier molecular compounds, we performed molecular dynamics calculations within the framework of the Density Functional Theory (DFT). These results demonstrated that the fragmentation of these heavier compounds strongly supports the experimental evidence of m/z = 39–42, 50, 60 (u) cations formation, which contributed to the broad local maximum in the total ionisation observed from 550 to 800 eV. This work reveals the reactivity induced by molecular anions colliding with hydrocarbons at high energies, processes that can take place in the interstellar medium under various local conditions.     

Resolving Deep Sub-Wavelength Scattering of Nanoscale Sidewalls Using Parametric Microscopy

The quantitative optical measurement of deep sub-wavelength features with sub-nanometer sensitivity addresses the measurement challenge in the semiconductor fabrication process. Optical scatterings from the sidewalls of patterned devices reveal abundant structural and material information. We demonstrated a parametric indirect microscopic imaging (PIMI) technique that enables recovery of the profile of wavelength-scale objects with deep sub-wavelength resolution, based on measuring and filtering the variations of far-field scattering intensities when the illumination was modulated. The finite-difference time-domain (FDTD) numerical simulation was performed, and the experimental results were compared with atomic force microscopic (AFM) images to verify the resolution improvement achieved with PIMI. This work may provide a new approach to exploring the detailed structure and material properties of sidewalls and edges in semiconductor-patterned devices with enhanced contrast and resolution, compared with using the conventional optical microscopy, while retaining its advantage of a wide field of view and relatively low cost.     

Reduction of chlorophenols and sludge management from paper industry wastewater using electrocoagulation process

ABSTRACT

In this study, electrocoagulation (EC) was used to determine the optimum conditions on the basis of maximum chemical oxygen demand (COD) and color removal. At the optimum conditions chlorophenols (CPs), biological oxygen demand and total organic carbon (TOC) were determined. The biodegradability of wastewater was increased significantly with 63% COD, 98% color, 61% TOC and overall 65.51% reductions in CPs. Further, the electro-coagulated sludge was characterized by using different analytical techniques to assist the physicochemical and elemental phases, to find-out better management option, reusability for plant growth and safe disposal. Additionally, aluminum content (70.62%) was successfully recovered from sludge.     

Synthesis of Self-Healing Bio-Based Tannic Acid-Based Methacrylates By Thermoreversible Diels–Alder Reaction

This investigation reports the effective use of the Diels–Alder (DA) click reaction in the preparation of self-healing bio-based dendritic methacrylates having reactive furfuryl functionality. Bio-based methacrylates were synthesized by modifying tannic acid with glycidyl methacrylate and furfuryl functionality was introduced by atom transfer radical polymerization with varied amount of furfuryl methacrylate monomer. The thermoreversible network was successfully achieved by DA and retro-DA reaction between the furfuryl groups and a bifunctional maleimide crosslinker, bismaleimide. This process was studied by nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and solvent exposure tests. Differential scanning calorimetry analysis was used to determine the endothermic retro-DA reaction in the DA adduct. The self-healing property of the above crosslinked material was demonstrated by monitoring the repair of a scratch in the polymer film upon heating and cooling. This was analyzed by scanning electron microscopy. POLYM. ENG. SCI., 60:140–150, 2020. © 2019 Society of Plastics Engineers     

Structure,properties, and applications of polyacrylonitrile/carbon nanotube (CNT) fibers at low CNT loading

Bi-component, polyacrylonitrile (PAN)/carbon nanotube (CNT) fibers were processed, at different core-sheath area ratios, by gel spinning. A percolated CNT network at 10 wt% CNT in the sheath enhanced electrical conductivity as compared to the neat PAN fiber, while PAN polymer in the core contributed to the good mechanical properties. Fibers with relatively thin sheath allowed overall CNT loading as low as 3.7 wt% to be made with good electrical conductivity, and PAN stabilization by Joule heating was demonstrated. Such fibers with combined good mechanical properties and electrical conductivity can also potentially be used for electrical heating of fabrics, for making smart textiles, and for electromagnetic interference shielding.     

Pd-Decorated Tungsten as Pt-Free Bimetallic Catalysts for Hydrogen Oxidation Reaction in Alkaline Electrolyte

Developing Pt-free catalysts for hydrogen oxidation reaction (HOR) in alkaline solution is becoming a key challenge in the development of anion exchange membrane fuel cells and electrochemical reactors. Herein, we present the preparation, HOR activity, and stability of Pd-decorated tungsten (Pd-d-W) catalysts. The Pd-d-W catalysts were prepared by the chemically activated surface of tungsten nanoparticles by Pd ions. The resultant bimetallic catalysts consisted of crystalline phases of both Pd and W nanoparticles. The CO stripping voltammograms and H-desorption (H_des) peak potential of hydrogen desorption in Pd suggests that the enhancement of HOR catalytic activity observed in Pd-d-W catalyst can be ascribed to the modification of electronic property of Pd and availability of OH_ad near-surface Pd atoms.     

Optical,electrical, mechanical,and thermal properties and non-isothermal decomposition behavior of poly(vinyl alcohol)–ZnO nanocomposites

Iranian Polymer Journal - Poly(vinyl alcohol) (PVA) nanocomposites incorporated with ZnO nanofiller were prepared and examined to study the influence of nanofiller on their properties. All the...     

Synthesis,characterization of β-CD based novel hydrogels with dual objectives of drug release and dye removal

Iranian Polymer Journal - In our recent work, we have reported on hydrogels devoid of cross-linkers. After observing the successful swelling and water retention properties, we have introduced...     

Ag2O–Al2O3–ZrO2 Trimetallic Nanocatalyst for High Performance Photodegradation of Nicosulfuron Herbicide

Topics in Catalysis - In the present study, Ag2O–Al2O3–ZrO2 based trimetallic oxide nanocatalyst was designed using simple microwave assisted reduction method. It was characterized...     

Gui-A-Gra Attenuates Testicular Dysfunction in Varicocele-Induced Rats via Oxidative Stress,ER Stress and Mitochondrial Apoptosis Pathway

Gui-A-Gra, a commercial insect powder from Gryllus bimaculatus, is registered as an edible insect by the Korean food and drug administration. The aim of this study was to investigate the effect of Gui-A-Gra on testicular damage induced by experimental left varicocele in male Sprague Dawley rats. A total of 72 rats were randomly divided into the following six groups (12 rats in each group): a normal control group (CTR), a group administrated with Gui-A-Gra 1.63 gm/kg (G1.63), a group administrated with Gui-A-Gra 6.5 gm/kg (G6.5), a varicocele (VC)-induced control group (VC), a VC-induced group administrated with Gui-A-Gra 1.63 gm/kg (VC + G1.63), and a VC-induced group administrated with Gui-A-Gra 6.5 gm/kg (VC + G6.5). Rats were administrated 1.63 or 6.5 gm/kg Gui-A-Gra once daily for 42 days. Indicators of sperm parameters, histopathology, reproductive hormones, oxidative stress, endoplasmic reticulum (ER) stress, inflammation, and mitochondrial apoptosis were analyzed to evaluate effects of Gui-A-Gra on VC-induced testicular dysfunction. Gui-A-Gra administration to VC-induced rats significantly (p < 0.05) increased sperm count and sperm motility, Johnsen score, spermatogenic cell density, serum testosterone, testicular superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase, GPx4, and steroidogenic acute regulatory protein (StAR) level. Moreover, pretreatment with Gui-A-Gra significantly (p < 0.05) decreased terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) positive cells/tubules, serum luteinizing hormone (LH), serum follicle-stimulating hormone (FSH), testicular tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), malondialdehyde (MDA), reactive oxygen species (ROS)/reactive nitrogen species (RNS) level, glucose-regulated protein-78 (Grp-78), phosphorylated c-Jun-N-terminal kinase (p-JNK), phosphorylated inositol-requiring transmembrane kinase/endoribonuclease 1α (p-IRE1α), cleaved caspase-3, and BCL2 associated X protein: B-cell lymphoma 2 (Bax: Bcl2) ratio in VC rats. These results suggest that protective effects of Gui-A-Gra on VC-induced testicular injury might be due to its antioxidant, anti-inflammatory, and androgenic activities that might be mediated via crosstalk of oxidative stress, ER stress, and mitochondrial apoptosis pathway.