Morphological changes and the content of free carboxyl groups in bovine collagen (type I) film under the influence of trypsin, hydrochloric acid (HCl) and ethylenediaminetetraacetic acid (EDTA) were studied. Incubation with trypsin and HCl was found to cause some delamination of the film and the appearance of some low-density spots. Incubation with EDTA did not cause any morphological changes. ...

The retention of copper (Cu) in saline–alkali soil (SAS) during long-term application biogas residue (BR) with a high concentration Cu raises concerns. In this work, the fate was detected using adsorption isotherms, scanning electron microscope—energy dispersive spectrometer, Fourier transform infrared X-ray diffraction, isothermal titration calorimetry, photoelectron spectroscopy, and microzon...

Isolated soil humic acid (HA) and commercial Aldrich HA were derivatized by esterification with methanol-thionyl and acetylation with acetic anhidride, in order to obtain derivatives with selectively blocked carboxyl and phenol groups, respectively. Results obtained by FT-IR spectroscopy and potentiometry show that the methanol-thionyl procedure is a selective, specific and efficient route for ...

Copolymers of methacrylic acid and natural terpene monomers (α-pinene; β-pinene; ∆3-karene) with the molecular weight (0.3–0.5)∙104 a content carboxyl groups 14.5–16.3 % were synthesized. For synthesized copolymers, hydrodynamic radius Kuhn segment, which characterizes flexibility polymer chain, determined, as well Huggins constant in aqueous saline solutions, concentration regions for formatio...

The stability mechanism and thermal properties of the system alumina-anionic polyacrylamide (PAM) was studied. The polymer's adsorption properties in dependence on the following parameters solution pH (in the range 3-9), temperature (in the range 15-35 °C), and carboxyl groups' content in the PAM chains (in the range 5-30 %) were examined. The turbidimetry method was applied for determination o...