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Quality of life in postostomy surgery patients: A new cross-sectional questionnaire.
In this work, rubber composites were fabricated by incorporation of manganese-zinc ferrite alone and in combination with carbon-based fillers into acrylonitrile-butadiene rubber. Electromagnetic parameters and electromagnetic interference (EMI) absorption shielding effectiveness of composite materials were examined in the frequency range 1 MHz-3 GHz. The influence of ferrite and fillers combination on thermal characteristics and mechanical properties of composites was investigated as well. The results revealed that ferrite imparts absorption shielding efficiency to the composites in tested frequency range. The absorption shielding effectiveness and absorption maxima of ferrite filled composites shifted to lower frequencies with increasing content of magnetic filler. The combination of carbon black and ferrite also resulted in the fabrication of efficient EMI shields. However, the EMI absorption shielding effectiveness was lower, which can be ascribed to higher electrical conductivity and higher permittivity of those materials. The highest conductivity and permittivity of composites filled with combination of carbon nanotubes and ferrite was responsible for the lowest absorption shielding effectiveness within the examined frequency range. The results also demonstrated that combination of ferrite with carbon-based fillers resulted in the enhancement of thermal conductivity and improvement of mechanical properties.A self-healing waterborne polyurethane (WPU) materials containing dynamic disulfide (SS) bond was prepared by introducing SS bond into polymer materials. The zeta potential revealed that all the synthesized WPU emulsions displayed excellent stability, and the particle size of them was about 100 nm. The characteristic peaks of N-H and S-S in urethane were verified by FTIR, and the chemical environment of all elements were confirmed by the XPS test. Furthermore, the tensile strength, self-healing process and self-healing efficiency of the materials were quantitatively evaluated by tensile measurements. The results showed that the self-healing efficiency could reach 96.14% when the sample was heat treated at 70 °C for 4 h. In addition, the material also showed a good reprocessing performance, and the tensile strength of the reprocessed film was 3.39 MPa.A new type of economical covalent organic framework material(COF), namely resin based covalent organic framework material, was prepared by combining resin and covalent organic framework material by hydrothermal synthesis, which was based on the preparation of traditional COF material(TpBD COF). The properties of the material and covalent organic framework material were compared in the way of characterization, and the possible reaction mechanism was analyzed. The solid phase extraction separation (SPE) ability of this material for four kinds of phenolic endocrine disrupting compounds (bisphenol F, bisphenol A, octylphenol and nonylphenol) in beverage samples was investigated. The results showed that the prepared COF materials had abundant internal channels, ordered structure, large specific surface area (TpBD COF 814.6 m2/g and resin based COF 623.9 m2/g) and good thermal stability (pyrolysis temperature was 443 °C and 437 °C, respectively). Solid phase extraction experiments demonstrated that the two COF mateThis paper presents the results of a comparative evaluation of the tensile strength behaviors of parts obtained by additive manufacturing using fused filament fabrication (FFF) technology. The study investigated the influences of the deposition printing parameters for both polymers and fiber-reinforced polymers. Polymeric materials that are widely used in FFF were selected, including acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), and nylon. Carbon and glass continuous fibers were used to reinforce the nylon matrix in composite materials. The study utilized two manufacturing methods. Polymers were manufactured using an Ultimaker 2 Extended+ device and the fiber-reinforced polymer specimens were obtained using a Markforged Mark Two printer. The entire set of specimens was eventually subjected to destructive monoaxial tensile tests to measure their responses. The main goal of this study was to estimate the effect of the different infill patterns applied (zig-zag, concentric, and four different orientations lines) on the mechanical properties of pure thermoplastic materials and reinforced polymers. Results show a spectacular increase in the tensile stress at break, which for polymers reaches an average value of 27.53 MPa compared to 94.51 MPa in the case of composites (increase of 70.87%). A similar increase occurs in the case of tensile stress at yield with values of 31.87 MPa and 105.98 MPa, respectively, which represents an increase of 69.93%. The influence of the infill of the fiber is decisive, reaching, in the 0-0 arrangement, mean values of 220.18 MPa for tensile stress at break and 198.26 MPa for tensile stress at yield.Complex engineering challenges are revealed in the wind industry; one of them is erosion at the leading edge of wind turbine blades. Water jet erosive wear tests on carbon-fiber reinforced polymer (CFRP) and glass-fiber reinforced polymer (GFRP) were performed in order to determine their resistance at the conditions tested. Vacuum Infusion Process (VIP) was used to obtain the composite materials. Eight layers of bidirectional carbon fabric (0/90°) and nine glass layers of bidirectional glass cloth were used to manufacture the plates. A water injection platform was utilized. The liquid was projected with a pressure of 150 bar on the surface of the specimens through a nozzle. The samples were located at 65 mm from the nozzle at an impact angle of 75°, with an exposure time of 10, 20 and 30 min. SEM and optical microscopy were used to observe the damage on surfaces. A 3D optical profilometer helped to determine the roughness and see the scar profiles. The results showed that the volume loss for glass fiber and carbon fiber were 10 and 19 mm3, respectively. This means that the resistance to water jet erosion in uncoated glass fiber was approximately two times lower than uncoated carbon fiber.Due to the pressing problems of today's world, regarding both the finding of new, environmentally friendly materials which have the potential to replace classic ones, and the need to limit the accelerated spread of bacteria in hospitals, offices and other types of spaces, many researchers have chosen to develop their work in this field. Thus, biopolymeric materials have evolved so much that they are gradually becoming able to remove fossil-based plastics from major industries, which are harmful to the environment and implicitly to human health. The biopolymer employed in the present study, Arboblend V2 Nature with silver nanoparticle content (AgNP) meets both aspects mentioned above. The main purpose of the paper is to replace several parts and products in operation which exhibit antibacterial action, preventing the colonization and proliferation of bacteria (Streptococcus pyogenes and Staphylococcus aureus, by using the submerged cultivation method), but also the possibility of degradation in different environments. The biopolymer characterization followed the thermal behavior of the samples, their structure and morphology through specific analyses, such as TGA (thermogravimetric analysis), DSC (differential scanning calorimetry), SEM (scanning electron microscopy) and XRD (X-ray diffraction). The obtained results offer the possibility of use of said biocomposite material in the medical field because of its antibacterial characteristics that have proved to be positive, and, therefore, suitable for such applications. The thermal degradation and the structure of the material highlighted the possibility of employing it in good conditions at temperatures up to 200 °C. Two types of samples were used for thermal analysis first, in the form of granules coated with silver nanoparticles, and second, test specimen cut from the sample obtained by injection molding from the coated granules with silver nanoparticles.The effects of MXene on the crystallization behavior of β-nucleated isotactic polypropylene (iPP) were comparatively studied. The commonly used MXene Ti3C2Tx was prepared by selective etching and its structure and morphology were studied in detail. Then MXene and a rare earth β-nucleating agent (NA) WBG-II were nucleated with iPP to prepare samples with different polymorphic compositions. The crystallization, melting behavior, and morphologies of neat iPP, iPP/MXene, iPP/WBG-II, and iPP/MXene/WBG-II were comparatively studied. The crystallization behavior analysis reveals that a competitive relationship exists between MXene and WBG-II when they were compounded as α and β nucleating agents. In the system, the β-nucleation efficiency (NE) of WBG-II is higher than α-NE of MXene. The β-phase has relatively low thermal stability and would transform to α-phase when cooled below a critical temperature.Injection research using aluminum flakes has been conducted to realize metallic textures on the surface of plastic products. Several studies have focused on the effect of the orientation and quality of the flakes when using conventional injection molding methods; however, limited studies have focused on the foam injection molding method. In this study, we examined the orientation of aluminum flakes through foam injection with an inert gas and observed the changes in texture using a spectrophotometer and a gloss meter. The mechanical properties were also studied because the rigidity of the product, which is affected by the weight reduction that occurs during foaming, is an important factor. The results demonstrate that under foam injection molding, reflectance and gloss increased by 6% and 7 GU, respectively, compared to those obtained using conventional injection molding; furthermore, impact strength and flexural modulus increased by 62% and 15%, respectively. The results of this research can be applied to incorporate esthetic improvements to products and to develop functional parts.Glucose Transporter-1 (GLUT-1) is considered to be a possible intrinsic marker of hypoxia in malignant tumors, which is an important factor in radioresistance of laryngocarcinoma. We speculated that the inhibition of GLUT-1 expression might improve the radiosensitivity of laryngocarcinoma. GLUT-1 siRNA was designed to inhibit the GLUT-1 expression, but the high molecular weight and difficult drug delivery limited the application. Herein, we constructed a glycolipid polymer chitosan oligosaccharide grafted stearic acid (CSSA) to conjugate siRNA via electrostatic interaction. The characteristics of CSSA and CSSA/siRNA were studied, as well as the radiosensitization effect of siRNA on human laryngocarcinoma epithelial (Hep-2) cells. Compared with the traditional commercial vector LipofectamineTM2000 (Lipo), CSSA exhibited lower cytotoxicity, more efficiently cellular uptake. Incubating with CSSA/siRNA, the survival rates of Hep-2 cells were significantly decreased comparing with either the group before transfection or Lipo/siRNA. CSSA is a promising carrier for efficient siRNA delivery and radiosensitization of laryngocarcinoma.
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