Materials Discovery最新文献

Recent years have witnessed growing demand for cost-effective natural bioproducts for therapeutic applications. In this work, cardamom husk was processed and turned into a protective shield for the hydrogel-drug conjugate. The seedless cardamom husk comprises of crude fibers and offers effective protection to the encapsulated hydrogel-drug matrix against degradation. Sodium alginate (SA) and gelatin were the biodegradable polymers utilized, while naproxen sodium (hydrophilic) and piperine (hydrophobic) were used as model drugs. The polymer-drug blend encased in this husk was engineered to give a long hour, zero-order release kinetics for both types of drugs. The hydrogel-drug conjugate was carefully optimized to achieve a controlled release with minimal or no use of cross-linkers. The viscosity of sodium alginate was used in such a way that the synthesis of a cross-linker free hydrogel-drug blend can be a reality. The husk was also found to be stable near sterilization temperatures. This research not only focusses on an available resource in nature but also showcases the role of modern methodology to convert this resource (cardamom husk) into a protective shield for a polymeric blend carrying drug molecules.

The addition of γ-Al₂O₃ support into the CuMnOx catalyst enhances the dispersion capacity as compared to unsupported CuMnO_x catalysts. There exist strong interactions between the copper, manganese oxide and γ-Al₂O₃ support. The effect of γ-Al₂O₃ on the dispersion, active states and reduction behavior of surface supported CuMnOx catalysts have been investigated by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), Scanning electron microscopy with energy-dispersed X-ray (SEM-EDX) and Brunauer Emmett Teller (BET) analysis. The characterization results confirm that Cu⁺, Mn²⁺ and Al mostly existed on the effective surface sites of the CuMnOx/γ-Al₂O₃ catalysts. These results indicate that there is a synergistic interaction between the copper, manganese and aluminum oxide, which is responsible for the high catalytic activity of CO oxidation reactions. In the CuMnOx/γ-Al₂O₃ catalysts, the 40%CuMnOx/γ-Al₂O₃ catalyst shows the highest catalytic activity for complete oxidation of CO at 130 °C temperature. The main aim of this paper is to find the optimum percentage of γ-Al₂O₃ support into the CuMnOx catalyst for total oxidation of CO at a low temperatures. Using γ-Al₂O₃ support in the CuMnOx catalyst lowers the cost without sacrificing the performance.

Titania nanotube (TNT) arrays with the length to diameter ratio of 85:1 were synthetized after anodizing the specimens at the anodizing voltage of 55 V for 2 h. Ultrasonic cleaning procedure in deionized water caused the formation of micro-cracks, clusters of TNT bundles and distortion of the nanotubes; however, acetone medium decreased the risk of fracture and the formation of clusters. To control the drug delivery rate, chitosan polymer was deposited on the surface of TNTs using dip-coating process. The total release of TNTs with 0, 0.29 and 0.45 μm chitosan coating thickness was about 6, 8 and 12 days, respectively.

The CuMnAgOx catalyst was prepared by the deposition-precipitation method and followed by calcination at 300 °C, which showed excellent activity and stability for carbon monoxide (CO) oxidation at low temperature. This paper describes the kinetics of catalytic air oxidation of CO over the CuMnAgOx catalyst and their kinetics data were collected in a plug flow tubular reactor. The data were collected under the following reaction conditions: 100 mg catalyst, 2.5% CO in air, total flow rate maintained 60 ml/min and temperature range 25–30 °C. The CO oxidation followed in a different reaction mechanism at a broad range of experimental temperature. A better tool for measuring the performance of CuMnAgOx catalyst for CO oxidation is the activation energy for the process and it’s used for the modeling and design of the catalytic converter. The data were fitted into the power law rate equation. The frequency factor and activation energy were found to be 2.7790 × 10⁵ (g mol)/(gcat h) and 16.977 kJ/g mol, respectively.