キレート多孔性膜を用いる有機ゲルマニウム化合物ｐ．ｔ‐ＣＥｔＧｅＯの回収

High-speed recovery of germanium in a convection-aided mode using functional porous hollow-fiber membranes

Preparation of an extractant-impregnated porous membrane for the high-speed separation of a metal ion

Water/acetone permeability of porous hollow-fiber membrane containing diethylamino groups on the grafted polymer branches.

Continuous synthesis of nano-drug particles by antisolvent crystallization using a porous hollow-fiber membrane module

Preparation of Aliquat 336-impregnated porous membrane

Adsorption of o-xylene and p-xylene from water by SWCNTs

Development of novel acid–base ions exchanger for basic dye removal: phosphoric acid doped pyrazole-g-polyglycidyl methacrylate

An epoxy-group-containing polymer brush anchored onto the pore surface of a porous hollow-fiber membrane, followed by the introduction of ionizable groups, extends due to mutual electrostatic repulsion, and holds proteins in multilayers. This phenomenon provides novel insight into the static structure and dynamic behavior of the charged polymer brush, and enables highly efficient protein recovery, chiral separation, and enzymatic reaction. Various proteins were recovered using the porous hollow-fiber membranes immobilizing the charged polymer brush at a higher rate and higher capacity compared to bead-packed column because of convection of the protein solution through the pores and multilayering of the proteins in the polymer brush.

Studies on uptake behavior of Hg(II) and Pb(II) by amine modified glycidyl methacrylate–styrene–N,N′-methylenebisacrylamide terpolymer

This paper describes a cycloisomaltooligosaccharide glucanotransferase (CITase)-multilayer-immobilized porous hollow-fiber membrane used as an enzyme bioreactor. Dextran, a substrate with an average molecular mass of 43000, is converted into seven- to nine-glucose-membered cycloisomaltooligosaccharides, effective as a preventive for dental caries, aided by convective transport of the substrate to the vicinity of the enzyme through the pores. Epoxy-group-containing graft chains were uniformly appended onto the surface of pores throughout a porous hollow-fiber membrane by radiation-induced graft polymerization. Subsequently, a diethylamino group was introduced, as an anion-exchange moiety, to the graft chains, which caused the chains to expand toward the interior of the pores due to mutual electrostatic repulsion. The expanding graft chain provided multilayer binding sites for CITase. Fifty-five milligrams of adsorbed CITase per gram of membrane is equivalent to the degree of multilayer binding of 5. Finally, 80% of the multilayer-adsorbed CITase was immobilized via enzymatic cross-linking with transglutaminase to prevent the leakage of enzymes. CITase, with a degree of multilayer immobilization of 4, produced the target cycloisomaltooligosaccharides at a conversion yield of 55% in weight at 310 K during permeation by the dextran solution at a space velocity defined as the permeation rate divided by membrane volume of 6 per hour.

Study on the local atomic structure of germanium in organic germanium compounds by EXAFS

In this study, the preparation of core/shell Ag@Fe3O4 nanoparticles (NPs) and its potential application toward highly sensitive electrochemical detection of furazolidone (FZD) have been reported. UV–visible spectroscopy, X-ray diffraction, scanning electron microscopy, and Zeta sizer are systematically carried out to confirm the formation, size distribution, and composition of Ag@Fe3O4 NPs. By computing the electrochemical characteristic parameters such as electrochemically active surface area (ECSA), electron-transfer resistance (Rct), standard heterogeneous rate constant (k0), adsorption capacity (Γ), and electron transfer rate constant (ks), the Ag@Fe3O4-modified electrode possessed remarkably enhanced electrochemical sensing performance for FZD determination compared to the unmodified screen-printed electrode (SPE). This enhancement of electrochemical activity can be attributed to the fast electron transfer kinetics and great adsorption capacity that arise from the synergistic coupling between the good electrical conductivity of the core AgNPs and the porosity of the protective Fe3O4 shell. Under optimum conditions, the Ag@Fe3O4-based electrochemical nanosensor exhibited not only high sensitivity toward FZD detection of 1.36 μA μM−1 cm−2 in the linear ranges from 0.5–15 μM and 15–100 μM, and low detection limit of 0.24 μM but also long-term stability, repeatability, and anti-interference ability. The applicability of the proposed sensing platform in honey and milk samples was also investigated.

The Maranhao lowlands present a diversified amount of wild animals, insects, and plants. The population has a food source based mostly on fishing, family farming, cattle, and buffalo farming. In this context, it is essential to investigate the anthropic impacts present in this environment. This work aims to verify the bioavailability in the adsorption of the potentially toxic metals Cu2+ and Cd2+ in natural and anthropized soils of the Maranhao lowlands. Soil samples were collected from two phytogeographic zones in Maranhao, the Cajari, and Viana municipalities. Determinations of organic matter, organic carbon, pH, PCZ, and quantification of the adsorbed metals in soil samples were carried out. The results showed that the pH and zero charge point (ZPC) parameters produced effects on the studied metal ions' adsorption capacity. The elements Cu2+ and Cd2+ described the adsorption favorably, with Cu2+ having greater adsorption capacity and bioavailability.

ZIF-8@Zn-MOF-74 core–shell metal–organic framework (MOF) with open metal sites: Synthesis, characterization, and gas adsorption performance

Effect of hydrophobic modification on carbon dioxide absorption using porous alumina (Al2O3) hollow fiber membrane contactor