Simple and Rapid Determination of Small Amounts of Sulphate in Cellulose Nitrate

Oxidative decomposition of cellulose nitrate was brought about by simple wet-ashing in a beaker with nitric acid and the digest-residue was further oxidised with 30% hydrogen peroxide, followed by evaporation to dryness. Interferences arising from use of hydrogen peroxide were later avoided by digesting with nitric acid and Evaporation to dryness. Complete oxidation was achieved in approximately one hour. The digests allow rapid sulphate determination by the lead nitrate-dithizone titration method. The method was greatly successful for analyzing both the unstabilized cellulose nitrates and those carefully stabilized materials.     

Efficient implementation of vector Preisach-type models using orthogonally coupled hysteresis operators

Vector hysteresis models are regarded as helpful tools that can be utilized in the simulation of multidimensional field-media interactions. Recently, substantial efforts have been focused on the refinement of vector Preisach-type models of hysteresis. The purpose of this paper is to present a computationally efficient vector Preisach-type hysteresis model constructed from only two scalar models having orthogonally inter-related elementary operators. Such a model is implemented via a linear neural network (LNN) fed from the outputs of discrete Hopfield neural network (DHNN) blocks having step activation functions. With this DHNN-LNN configuration, it is possible to carry out the identification process using well-established widely available algorithms. Details of the model, its identification, and experimental testing are presented.     

Tailoring of oxidized starch's adhesion using crosslinker and adhesion promotor for the recycling of fiberboards

The growing interest in recycling waste medium density fiberboards (MDFs) is driving the development of new adhesives that provide sufficient adhesion, and allow disintegration of the waste MDFs. Described in here is the preparation of adhesives based on oxidized starch (OS) in combination with blocked-polymeric 4-4 diphenylmethane diisocyanate (B-pMDI) as a crosslinker and poly(vinyl alcohol) (PVA) as an adhesion promotor for the recycling of waste MDFs. The  COOH groups of OS were reacted with  NCO groups of B-pMDI to form amide linkages, and the  CHO groups were reacted with  OH groups of PVA through hydrogen bonding. Further, when applied as an adhesive, the OS formed ester linkages with  OH of MDF fibers. As the results, MDF bonded with 1% B-pMDI/15% PVA/OS adhesive had an internal bonding strength of 0.13 MPa, 0.01 mg L⁻¹ of formaldehyde emission (FE), and 12% of degree of fiber disintegration. These results demonstrate that the B-pMDI/PVA/OS adhesive is a possible alternative to the current urea–formaldehyde resins for the recycling of waste MDFs into recycled MDFs without FE. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47966.     

Initial Magnetic Permeability of M-Type BaFe<Subscript>12</Subscript><Emphasis Type="Italic">O</Emphasis><Subscript>19</Subscript>-Polystyrene Composite

We reveal the potential effect of inclusion of M-type BaFe₁₂ O ₁₉ (BaM) particles in polystyrene (PS) polymer. BaM particles are attached rather well to a PS matrix with variable sizes and shapes. It demonstrated that the incorporation of BaM particles into a PS polymer would largely increase the initial magnetic permeability of BaM. Furthermore, it is significantly larger than corresponding values of commercially sintered MnZn ferrite. Therefore, BaM-PS composite imposes itself as a potential material in several applications such as flux amplifier and inductors.     

High Performance of UiO-66 Metal–Organic Framework Modified with Melamine for Uptaking of Lead and Cadmium from Aqueous Solutions

Journal of Inorganic and Organometallic Polymers and Materials - In this paper, UiO-66 metal–organic framework (MOF) was prepared by a hydrothermal method and modified consequently with...     

Calculation of heating power generated from ferromagnetic thermal seed (PdCo-PdNi-CuNi) alloys used as interstitial hyperthermia implants

High quality heating device made of ferromagnetic alloy (thermal seed) was developed for hyperthermia treatment of cancer. The device generates sufficient heat at room temperature and stops heating at the Curie temperature T _c. The power dissipated from each seed was calculated from the area enclosed by the hysteresis loop. A new mathematical formula for the calculation of heating power was derived and showed good agreement with those calculated from hysteresis loop and calorimetric method.     

Enhanced Antimicrobial Activity of Biocompatible Bacterial Cellulose Films via Dual Synergistic Action of Curcumin and Triangular Silver Nanoplates

Curcumin and triangular silver nanoplates (TSNP)-incorporated bacterial cellulose (BC) films present an ideal antimicrobial material for biomedical applications as they afford a complete set of requirements, including a broad range of long-lasting potency and superior efficacy antimicrobial activity, combined with low toxicity. Here, BC was produced by Komagataeibacter medellinensis ID13488 strain in the presence of curcumin in the production medium (2 and 10%). TSNP were incorporated in the produced BC/curcumin films using ex situ method (21.34 ppm) and the antimicrobial activity was evaluated against Escherichia coli ATCC95922 and Staphylococcus aureus ATCC25923 bacterial strains. Biological activity of these natural products was assessed in cytotoxicity assay against lung fibroblasts and in vivo using Caenorhabditis elegans and Danio rerio as model organisms. Derived films have shown excellent antimicrobial performance with growth inhibition up to 67% for E. coli and 95% for S. aureus. In a highly positive synergistic interaction, BC films with 10% curcumin and incorporated TSNP have shown reduced toxicity with 80% MRC5 cells survival rate. It was shown that only 100% concentrations of film extracts induce low toxicity effect on model organisms’ development. The combined and synergistic advanced anti-infective functionalities of the curcumin and TSNP incorporated in BC have a high potential for development for application within the clinical setting.