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The selection of disperse dye is one of the most important factors in supercritical fluid carbon dioxide dyeing. In particular, PET fiber, which is widely applied to supercritical fluid dyeing, has a hydrophobic property and a low affinity with other ionic dyes, so it is very important to prepare criteria for the selection of disperse dyes. In this study, the affinity between PET fibers and six dyes was predicted by three methods, and the reliability of the proposed prediction methods was verified through experimental analysis after the supercritical dyeing process. The three methods used to predict the affinity of dyes to PET fibers are IOB (inorganic organic balance), chemical potentials, and surface free energy. To verify the reliability of the proposed prediction method, affinity and dyeability were evaluated through experiments. As a result of the experiment, disperse red 167 among the dyes used showed the best affinity and dyeability with PET, and similar results were also obtained through prediction methods. [ABSTRACT FROM AUTHOR]

In this study, the antimicrobial and photodegradation properties of nylon fabric were improved by chemical treatment using 3-mercaptopropyltrimethoxysilane (3-MPTMS), which binds to photocatalyst TiO2, on a nylon fabric surface. The nylon fibers were impregnated with a solution containing isopropanol, titanium dioxide (TiO2), and 3-MPTMS at optimum ratios, and then stirred for 90 min. To remove the nonreactive impurities, the sample was washed twice with isopropanol and distilled water, and then dried. The TiO2 concentration, agitation temperature, and time were varied to determine suitable coating conditions for attachment to the nylon surface; the resulting properties were confirmed by scanning electron microscopy/energy dispersive spectroscopy. To evaluate the antimicrobial and photodegradation properties of TiO2, antimicrobial tests were conducted using the microbial reduction method and contact angle tests. The fiber contamination rate was measured by computer color matching after the sample was contaminated with methylene blue. Moreover, the antimicrobial activity of Staphylococcus aureus and Escherichia coli strains on the treated nylon was investigated. [ABSTRACT FROM AUTHOR]

Microbial processes can affect the environmental behavior of priority radionuclides, and understanding these reactions is essential for the safe management of radioactive wastes and can contribute to the remediation of radionuclide-contaminated land. Underlying mechanisms that can control radionuclide solubility in biogeochemical systems can range from biosorption and biomineralization process, through direct (enzymatic) and indirect redox transformations. The mechanisms of enzyme-mediated reduction of problematic actinides, in principal, uranium (U), but including neptunium (Np), plutonium (Pu) and Americium (Am), are described in this review. In addition, the mechanisms by which the fission products technetium (Tc), cesium (Cs), and strontium (Sr) are removed from a solution by microorganisms are also described. The present review discusses the status of these microbiological processes, and the potential for cost-effective and scalable in situ remediation of radioactive waste. [ABSTRACT FROM AUTHOR]

Obesity is the fifth leading cause of death globally. At least 2.8 million adults die each year as a result of being overweight. Therefore, the development of an efficient lipid inhibitor for the biological effects of obesity is highly needed. The discovery of bioactive compounds from food is one possible way to control obesity and to prevent or reduce the risks of various obesity-related diseases. In this study, we found that 7,3′,4′-trihydroxyisoflavone from Korean soybean paste has remarkable anti-obesity activity in vitro and in vivo. Treatment with 7,3′,4′-trihydroxyisoflavone significantly reduced the adipose tissue weight to 1.6/100 g of body weight in high-fat mice. In addition, in 7,3′,4′-trihydroxyisoflavone-treated mice, a significant reduction in the serum triglyceride and T-cholesterol was observed at 29 and 37 %, respectively. These results support the hypothesis that 7,3′,4′-trihydroxyisoflavone is expected to create a therapeutic interest in its use for the treatment of obesity. [ABSTRACT FROM AUTHOR]

Two highly supercritical CO-soluble, poly(vinyl acetate) (PVAc)-based macro-reversible addition-fragmentation chain transfer (RAFT) agents were synthesized. The RAFT agents were used for the first time in RAFT/macromolecular design via the interchange of xanthates (MADIX) and polymerization of vinyl acetate (VAc) and vinyl pivalate (VPi) in supercritical carbon dioxide (scCO). A homopolymer PVAc and a block copolymer PVAc- b-PVPi made by RAFT/MADIX polymerization were characterized, and the effects of time and RAFT agents on polymerization were examined. For the 8.4 wt% RAFT agent in VAc, the molecular mass (M) of homopolymer PVAc was 26,000 g mol and PDI was 1.35. For the copolymerization of VPi using 9.8 wt% PVAc-RAFT agent in VPi for 24 h, the M and PDI of PVAc- b-PVPi reached 32,400 g mol and 1.42, respectively. These results suggest that the polydispersity can be controlled during the clean production of PVAc and PVPi by RAFT/MADIX polymerization in scCO. [ABSTRACT FROM AUTHOR]

Here, we present a simple method for controlling the density of Au nanoparticles (Au NPs) on a modified silicon substrate, by destabilizing the colloidal Au NPs with 3-mercaptopropyltrimethoxylsilane (3-MPTMS) for microelectromechanical-system-based applications to reduce tribological issues. A silicon surface was pretreated with a 3-MPTMS solution, immediately after which thiolated Au NPs were added to it, resulting in their uniform deposition on the silicon substrate. Without any material property change of the colloidal Au NPs, we observed the formation of large clusters Au NPs on the modified silicon surface. Analysis by scanning electron microscopy with energy dispersive X-ray spectroscopy indicated that the addition of 3-MPTMS resulted in an alternation of the chemical characteristics of the solution. Atomic force microscopy imaging supported the notion that silicon surface modification is the most important factor on tribological properties of materials along with ligand-modified Au NPs. The density of Au NPs on a silicon surface was significantly dependent on several factors, including the concentration of colloidal Au NPs, deposition time, and concentration of 3-MPTMS solution, while temperature range which was used throughout experiment was determined to have no significant effect. A relatively high density of Au NPs forms on the silicon surface as the concentrations of Au NPs and 3-MPTMS are increased. In addition, the maximum deposition of Au NPs on silicon wafer was observed at 3 h, while the effects of temperature variation were minimal. [ABSTRACT FROM AUTHOR]