PubMed · 13123345
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
W SCHULZE-BRUGGEMANN, G STRIETZEL. 1953. [Experiments regarding intrathoracic perlon plombe].. https://pubmed.ncbi.nlm.nih.gov/13123345/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
The flexibility and simplicity of stir bar sorption extraction (SBSE) have been combined with the selectivity of molecularly imprinted polymers (MIP). Stir bars were coated reproducible with a 180 microm film formed from a formic acid solution of nylon-6 polymer either nonimprinted or imprinted with monocrotophos. Time sorption profiles were measured for the extraction of monocrotophos from dichloromethane at the concentration of 10-200 micromol/L levels with both types of films in order to compare extraction characteristics. The results indicated that the MIP coated layer showed remarkable high affinity toward monocrotophos and equilibrium adsorption was attained rapidly (60 min) in contrast to free standing molecularly imprinted polymer in which equilibrium adsorption was normally attained after several hours. The stir bars coated with MIP films were capable of extracting four structural analogues of monocrotophos from dichloromethane solution, which suggests that both the amino group and PO part of these molecules is responsible for interaction with the imprinted polymer. Evidence was also presented by FT-IR analysis that the amide-hydrogen-bonding interaction between the MIP-coated films and monocrotophos was originated for monocrotophos recognition. To achieve selective extraction of monocrotophos from sample, stir bars coated with MIP films were washed with 10% (v/v) acetic acid/methanol and methanol. Clean extracts and yields of 95% were obtained, demonstrating the suitability of stir bar coated with MIP films for the analysis of environmental and biological samples. Compared with traditional MIP and SBSE, the MIP-coated film showed not only the high selectivity but also the rapid equilibrium adsorption.
Grafting of poly(N-vinylcaprolactam) side chains onto a hydrophilic dextran backbone was found to provide the dextran with new, thermoresponsive properties in aqueous solutions. Depending on its solution concentration, the resulting dextran derivative could exhibit a temperature-induced phase-transition and critical transition temperature (T(c)). Different anions and cations of added salts, including five potassium salts and five alkali-metal chlorides, were observed to influence the T(c) value of its aqueous solution. Except for potassium iodide, all added salts were found to lower the T(c) value. The addition of the surfactant, cationic cetyltrimethylammonium bromide or anionic sodium dodecyl sulfate, resulted in an increase of the T(c) value. With the help of the Coomassie Brilliant Blue dye as a polarity probe, the formation of hydrophobic aggregates above the T(c) was revealed for this new dextran derivative in aqueous solution.
An exfoliated polyamide 6 (PA6)/layered double hydroxide (LDH) nanocomposite has been successfully prepared via an in situ intercalative polymerization procedure. The original LDH surface is hydrophilic. After an ion exchange reaction of LDH with sodium stearate (SS), the organic anions intercalated into the interlayer space of LDH, adopting a double-layer inclined structure, and the surface of the organic-modified LDH became hydrophobic. An exfoliated PA6/LDH nanocomposite has been obtained via in situ intercalative polymerization. Its microstructure was characterized by a combination of wide-angle X-ray diffraction (WAXD) and transmission electron microscopic (TEM) techniques. The positively charged inorganic platelets of LDH were dramatically exfoliated and homogeneously dispersed in the PA6 matrix.