As the "vector" of heavy metals in the aquatic environment, microplastics (MPs) have a great influence on the migration and transformation of heavy metals. In this study, the adsorption of polypropylene (PP), polyethylene (PE) and polystyrene (PS) on two models of heavy metals after UV aging and environmental variables (ionic coexistence, pH, salinity, and fulvic acid) were comprehensively explored on adsorption. The results show that new oxidation functional groups are formed and their hydrophilicity is enhanced after MPs aging.
View Article and Find Full Text PDFMetal effects on the gas sensing behavior of metal complexes of 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin (THPP) thin film was investigated in terms of detecting NO gas by the planar optical waveguide. For this purpose, several THPP and metal complexes were synthesized with different central metal ions: Co(II), Ni(II), Cu(II), and Zn(II). Planar optical gas sensors were fabricated with the metalloporphyrins deposited on K ion-exchanged soda-lime glass substrate with the spin coating method serving as host matrices for gas interaction.
View Article and Find Full Text PDFThe sensing behavior of a thin film composed of metal-free 5, 10, 15, 20-tetrakis (p-hydroxy phenyl) porphyrin and zinc phthalocyanine complex towards m-xylene, styrene, and HCl vapors in a homemade planar optical waveguide (POWG), was studied at room temperature. The thin film was deposited on the surface of potassium ion-exchanged glass substrate, using vacuum spin-coating method, and a semiconductor laser light (532 nm) as the guiding light. Opto-chemical changes of the film exposing with hydrochloric gas, m-xylene, and styrene vapor, were analyzed firstly with UV-Vis spectroscopy.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2021
Optical waveguide gas sensor with bromocresol purple (BCP) nano-film (70-80 nm) composited with silicone deposited on surface of K-ion exchanged glass slide was fabricated and applied to detect amine gases released during mutton spoilage to test mutton freshness with the help of laser light (632 m). Gas sensing measurements (output light intensity vs. time) proved its high selectivity and good sensitivity (0.
View Article and Find Full Text PDFIn this work, sodium dodecyl benzene sulfonate (SDBS) was used as a dispersing agent; a WO nanoparticle suspension was used as a sensing material. The SDBS-WO thin film/Sn-doped glass optical waveguide sensor element was prepared by spin coating. The sensing material was characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and field-emission scanning electron microscopy (FESEM).
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
February 2015
Surfaces of natural sand particles were modified with (3-chloropropyl) trichlorosilane, so that bridging groups were introduced on the surfaces of natural sand particles; By grafting polyacrylonitrile onto the modified surfaces of the natural sand particles, a novelpolyacrylonitrile/natural sand composite material was prepared from the acrylonitrile, the azobisisobutyronitrile, the divinylbenzene and the modified natural sand particles, which are as functional monomer, initiator, either skeleton monomer or cross-linking agent and carrier respectively; the composite materials were characterized by using infrared spectroscopy and scanning electron microscopy; On the FTIR spectrum, the main characteristic peaks of various functional groups including nitrile, benzene ring, and silicon hydroxyl, which were from functional monomer, cross-linking agent and carrier respectively, were observed. On the SEM, two different cross section morphologies having different density which were from acrylonitrile and modified sand particles were observed; This proved that the polyacrylonitrile was decorated on modified sand particles during our preparation process. After preparing the composite materials, micro-column of separation and preconcentration was prepared using the composite materials as filler; the adsorption of some toxic heavy metal ions onto the composite materials was observed by flame atomic absorption spectrometry (FAAS); The results show that the adsorption of Pb2+ onto the composite materials was more stronger than the absorption of other toxic heavy metal ions, therefore, in this paper, the adsorption of Pb2+ onto the composite materials was mainly studied, at room temperature, when pH and flow rate of solution were 5.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
June 2012
The crosslinked polymer beads was synthesized by free emulsion polymerization using maleic anhydride and styrene. The chemical structure and morphology of the polymer beads were analyzed using FTIR and SEM. And the dynamic adsorption properties of beads for Pb(II) was studied by atomic adsorption spectrometry(AAS).
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
November 2011
The present research was aimed at the study of adsorption properties of lead ion on natural sand particle (NSP) by FAAS and at the development of NSP as an adsorbent used in the removal and preconcentration of lead(II) ion in aqueous solution by adsorption. Particle structure and size distribution, surface morphology, specific surface area, functional radical of NSP and adsorption properties of lead ion onto NSP and factors which affect the adsorption capacity were analyzed using FTIR, SEM, NSA and FAAS. The adsorption condition such as acidity of solution, flow rate and time etc were optimized.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
June 2011
With lead ion template, acrylic acid as functional monomer, potassium persulfate as initiator, strytrene as framework monomer, lead ion imprinted polymers (Pb(II)-IIPs) were prepared using free emulsion polymerization method. The structure and morphology of the polymers were analyzed by UV-spectra, FTIR and scanning electron microscopy. The adsorption/ desorption and selectivity for Pb2+ were investigated by flame atomic absorption spectrometry (FAAS) as the detection means.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
April 2010
The crosslinked polymer polyacrylonitrile was synthesized by suspension polymerization using acrylonitrile and divinylbenzene. It has been used as adsorbent of some toxic heavy metals in environmental waters. Its adsorption for metals and the factors which affect the adsorption capacity were studied by atomic absorption spectrometry (AAS).
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
June 2008
The rapid and direct method of selection of the matrix modifier for the determination of trace lead in soil watered with waste water by graphite furnace atomic absorption spectrometry under the best matrix modifier selected has been developed. The effect of the matrix modifiers including NH4 Hz2PO4, (NH4)3PO4, NH4CI, Pd-Mg, NH4H2PO4+MgNO3+NH4NO3 etc. was determined by using graphite furnace atomic absorption spectroscopy.
View Article and Find Full Text PDFGuang Pu Xue Yu Guang Pu Fen Xi
December 2005
A rapid and sensitive method for the sequential determination of Cr(VI) and Cr(III) in water samples based on flame atomic absorption spectrometry with TOA-benzene extraction separation system has been developed. In the H2SO4 medium. Cr(VI) in sample solution was extracted into the organic phase by using the TOA-Benzene and Cr(III) remained in the water phase.
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