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The zero-valent iron (ZVI) immobilized in an alginate microsphere was prepared by using sodium alginate as a support material. The characteristics of the Fe

To investigate the effect of hydrophobic and hydrophilic polypropylene hollow fiber membranes (PPHFMs) applied in membrane bioreactors (MBR), the fouling behaviors of membrane surfaces and pores have been tested. The structural and morphological features on the membrane surface were characterized using attenuated total reflection-Fourier transform infrared spectroscopy, field emission scanning electron microscopy, atomic force microscope, energy dispersive X-ray spectroscopy and laser granularity distribution analysis. The results showed that significantly more polysaccharide, protein and inorganic ingredients were accumulated in the original membrane compared to the hydrophilic membrane. Furthermore, it was found that the pore size influenced the particle distribution and accumulation, such that smaller pore size membranes tended to contain fewer pollutants and a narrow size distribution. Under a constant flux of 11.5 L/m2 h, the transmembrane pressure (TMP) varied narrowly between 38 and 53 KPa....

Poly(vinylidene fluoride) (PVDF)/1-butyl-2,3-dimethylimidazolium Tetrafluoroborate ([BMMIm][BF4]) flat sheet membranes were made via thermally induced phase separation (TIPS) melt technology, and [BMMIm][BF4]) was used as a diluent. The prepared membranes were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) and etc. Furthermore, [BMMIm][BF4] as a liquid-diluent was effectively recovered by vacuum distillation. In conclusion, this work may provide a green and sustainable preparation method to produce PVDF membranes via TIPS.

The polypropylene (PP) fibers were chosen as substrate materials. Functional fibers containing iron were prepared by UV irradiation-coordination method, and then Pd/Fe bimetallic composite catalytic fibers were prepared by replacement reaction and used for the removement of N-nitrosodimethylamine (NDMA). The effect of monomer concentration, the pH of the reaction system and reaction temperature on NDMA catalytic degradation was investigated. The results indicate that the degradation rate of NDMA can reach 69.97% when the AA monomer concentration is 20%, which is the best catalytic reduction effect of composite catalytic fiber on NDMA. The pH of solution and reaction temperature can not greatly influence the catalytic reduction of NDMA.

Fluorescent DNA probes based on the fluorescence resonance energy transfer (FRET) were presented in this paper when AuNPs were as the energy acceptors and CdTe quantum dots and CdTe/SiO2 core/shell nanoparticles were as the energy acceptors, respectively. The DNA probes were prepared when energy donors and acceptors were conjugated with two single-stranded complementary oligonucleotides and hybridized with each other and the fluorescent intensity of probes could be decreased. The quenching efficiency of DNA probe was about 67 % when CdTe QDs were as the energy donors, while that of DNA probe was about 75 % when CdTe/SiO2 fluorescent core/shell nanoparticles were as the energy acceptors, which indicated that CdTe/SiO2 core/shell nanoparticles were suitable donors compared with CdTe QDs in DNA probe field.

Marcoporous silica hollow microspheres were prepared by poly (acrylic acid)@poly (ethyleneglycol dimethacrylate-co-4-vinylpyridine) (PAA@P(EGDMA-co-VPy)) composite particles with raspberry-like structure as the template. P(EGDMA-co-VPy) and PAA microspheres were prepared by distillation precipitation polymerization respectively. The raspberry-like organic composite polymer particles were obtained through the self-assembly of PAA microspheres on P(EGDMA-co-VPy) microspheres. Then, Silica layer was coated on the composite particles with Stöber method in an alkaline environment. The marcoporous silica hollow microspheres were received after the calcination to remove the organic template. The diameter of the marcoporous silica hollow microspheres, hollow inner core and the pore size of silica layer was about 2.0 μm, 1.5 μm and 20-130 nm, respectively.

This study reports inorganic nanoparticles modified molecular beacons as fluorescent DNA biosensors. MBs were modified by using CdTe quantum dots as energy donors and 4-(4'-(dimethylamino) phenylazo) benzoic acid, black hole quencher 1 and Au nanoparticles as energy acceptors, respectively. CdTe quantum dots were linked to molecular beacons when 1-ethyl-3-(3-dimethylaminopropyl) carbodi-imide hydrochloride was added. The fluorescence intensity of the modified molecular beacons decreased tremendously compared to the fluorescence intensity of CdTe quantum dots, which indicated that the fluorescence resonance energy transfer occurred between the donors and acceptors. The results indicated that this type of molecular beacons has high specificity and can be used to distinguish complementary DNA and its mutants.

A tridentate N,O-donor, 1,3-bis(3,5-dimethylpyrazol-1-yl)propan-2-ol (HL), has been employed to synthesize cyano-bridged complexes and six heterometallic complexes with [Cu2L2] or [Cu2L2(H2O)] have been generated by using slow diffusion. With slightly different synthetic conditions, subtle variations in the crystal structures of the complexes occur. [Cu2L2][Fe(CN)5NO]⋅2CH3CN (1) and [Cu2L2][Fe(CN)5NO]⋅H2O (2), synthesized in different solvents with the same precursor, exhibit a very similar 1-D zig-zag chain motif in different space groups, P21 and P-1, respectively. Similarly, [Cu2L2(H2O)][Ni(CN)4]·H2O (3) and [Cu2L2][Ni(CN)4]⋅H2O (4), synthesized with different diffusion methods, feature trinuclear and 1-D zig-zag chain structures, which indicates a solvent effect of water. [Cu2L2(H2O)]2[Cu2L2][W(CN)8]2·8H2O (5) is composed of two [W(CN)8]3− and three [Cu2L2]2+ units. In the octanuclear structure, [W(CN)8]3− and one [Cu2L2]2+ bridge and the other two [Cu2L2]2+ are terminal to stop extending the 1-D stru...

Calcium polyacrylate/alginate (CPA/A) hybrid polymer microspheres with the imprinting of bovine serum albumin (BSA) were prepared via Ca2+ crosslinking of sodium polyacrylate (SPA), BSA and sodium alginate (SA) in inverse suspension. The specific rebinding properties of BSA imprinted hydrogel microspheres (CPA/A MIPMs) were investigated by controlling pH value from the viewpoint of adjusting the process of gelling, removing template and rebinding. The optimized pH values in gelling, removing template and rebinding process was 4.1, 8.3 and 4.2, respectively.

In order to improve the water flux of PVDF hollow-fiber membrane, acrylic acid (AA) was grafted onto PVDF membrane matrix through electron beam irradiation in isopropanol/water aqueous solution. The grafting conditions were optimized and the effects of grafting parameters were investigated. Fourier transform infrared attenuated total reflection spectroscopy (FTIR-ATR) was used to characterize the chemical changes of the PVDF matrix. The morphological behaviors have been estimated using field emitting scanning electron microscopy (FESEM). The present study suggested that the grafting degree played a dominant role in the water flux of AA grafted PVDF membrane (PVDF-g-AA). The pure water flux of grafted membrane increased to 467.8 L/m2h, nearly two times than the original membrane.

In this work, an acrylic-polypropylene grafting copolymer (PP-g-AA) was prepared by 60Co γ-rays irradiation grafting with acrylic acid (AA) onto polypropylene (PP) fiber. The esterification PP-g-AA fiber (PP-g-COOR) was prepared by the esterification of PP-g-AA with C8 alcohol via SOCl2 as the intermediate. The PP-g-COOR fiber was utilized to adsorb and enrich trace dibutyl phthalate (DBP) in water. The results indicated that PP-g-COOR fiber exhibited a good adsorption property of DBP. The adsorption property of PP-g-COOR fiber was greatly enlarged 25 times than the PP-g-AA. The distribution coefficient of DBP on PP-g-COOR fiber depended on the pH values of aqueous phase and the initial concentration of DBP. In general, the PP-g-COOR fiber was better for the adsorption and enrichment of DBP.

Calcium phosphate/polyacrylate/alginate hybrid polymer microspheres with bovine serum albumin (BSA) embedded and coated on the surface were prepared with (NH4)2HPO4, sodium polyacrylate (SPA) and sodium alginate (SA) via Ca2+ crosslinking in inverse suspension. Rebinding behaviors of the microspheres were evaluated. The factors influencing the imprinting efficiency (IE) of imprinted microspheres were also studied, including the concentration of CaCl2, template content and pH values in rebinding solutions. Selectivity tests showed that the imprinted microspheres exhibited good recognition property for the template protein.

A weak acid cation exchange fiber was prepared by γ-ray pre-radiation induced grafting of acrylic acid (AA) onto polypropylene (PP) non-woven without removal of the polymerization inhibitor in acrylic acid. The factors influenced the grafting degree were discussed, such as radiation dose, initiator concentration, monomer concentration, storage time and bath ratio. It is found that the initiator 2, 2'-Azobisisobutyronitrile (AIBN) was necessary for the increased grafting of AA without removing the inhibitor in AA.

A novel photoresponsive hydrogels of poly(acrylamide-co-acrylamido azobenzene) (p(AAm-co-AAAB)) consisting of acrylamide (AAm) and acrylamido azobenzene (AAAB) was prepared via a free-radical copolymerization route by using 2,2’-azobisisobutyronitrile (AIBN) as initiator, and N,N-methylene bisacrylamide (MBAA) as a crosslinking agent. The photoresponsive behaviors were studied. The variations of volume and swelling ratio of p(AAm-co-AAAB) hydrogels under UV or visible light irradiation indicated that PAAm hydrogels have no UV light sensitivity, but with the increase of the time of UV irradiation, the volume and swelling ratio of p(AAm-co-AAAB) hydrogels decreased, and then increased with the extending of the time after UV irradiation for the isomerization. The results disclosed that the copolymer hydrogels possess good photoresponsive property to UV irradiation, and the photoresponsive behavior is reversible with the transformation between UV and visible light irradiation.

Polysulfone (PSf) hollow fiber ultrafiltration (UF) membranes were surface-modified by the UV-induced graft polymerization of 2-acrylamido-2-methylpropanesulfonic acid (AMPS). Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and scanning electron microscope (SEM) were employed to characterize the structural and morphological changes on the membrane surface. Water contact angle of PSf-g-AMPS membrane surface decreased to 15.45° when AMPS concentration was 2 wt.%, which was nearly 35° lower than that of the unmodified membrane. The results of streaming potential measurement at different pressures implied the negatively charged characteristic of the PSf-g-AMPS membrane. The flux of PSf-g-AMPS membrane increased about 60% as compared to original PSf membrane and the rejection of heparin sodium for PSf-g-AMPS membrane achieved 78%, which was about 4 times that of PSf membrane at 0.04 MPa.

The purpose of this paper was to evaluate the capacity of anion ion exchange fiber to uptake the heavy metal(Co2+、Cu2+、Zn2+、Cd2+、Pb2+、Ag+) from the water. A new polyamine-type ion exchange fiber(IEF) based on polyacrylonitrile (PAN) with higher exchange capacities was prepared by crosslinking through hydrazine hydrate, followed reacting with diethylene triamine. FT-IR analysis indicated that amine, imido, acylamino and carboxyl groups were introduced into PAN fiber through the surface modified reaction of cross linking and amination. The structures of the IEF were characterized by means of SEM. The results showed that the surface of fiber became rougher and thicker and more heterogeneous. The static and dynamic adsorption experiments demonstrated the high selective adsorption property of the IEF for Ag+ and Cu2+. Furthermore, the adsorption mechanism for the metal ions with IEF was investigated with the FT-IR spectra studies.

The mixture of CuCl2·2H2O and K3[Fe(CN)6] reacts with a series of flexible bis(pyrazole-1-yl)alkane ligands, Pz-(CH2)n-Pz (n = 1 for bpzm, n = 2 for bpze, n = 3 for bpzp, and n = 4 for bpzb), under hydrothermal conditions to produce four new copper(I) cyanide complexes: {[Cu2(CN)2(bpzm)]}n (1), {[Cu2(CN)2(bpze)]}n (2), {[Cu2(CN)2(bpzp)]}n (3), and {[Cu(CN)(bpzb)]}n (4), respectively. The X-ray analyses reveal that 1 exhibits a novel three-dimensional (3D) honeycomb-like framework, 2 shows a 2-fold interpenetration two-dimensional (2D) network, 3 exhibits a 3D structure, and 4 forms a 2D grid-like structure. An interesting odd−even phenomenon is observed in the complexes: when n is odd (n is the number of the CH2 spacer of ligands), the resulting complex exhibits a 3D framework, whereas when n is even, a 2D structure is generated. It could be explained that the numbers have a close relationship with dihedral angles among pyrazole rings of the ligands which have a great effect on the structures. Luminescent...

A novel type of weakly acidic cation exchange fiber have been prepared by 60 Co irradiation grafting with acrylic acid onto the polytetrafluoroethylene (PTFE) fiber. The exchange capacity of the grafted fiber is 3.06 mmol/g. The pH titration curve of the grafted fiber showed there is a sudden jump when pH is round 6–10, and the acidity of the grafted fiber is stronger than that of commercial weakly acidic exchange D-152 resin. The grafted fiber showed the excellent selectivity of static and dynamic adsorption for Cu 2+ , La 3+ and Pb 2+ when Mg 2+ , Ca 2+ , Cr 3+ , Co 2+ , Ni 3+ , Cu 2+ , Ag + , La 3+ , Pb 2+ were coexisted. The grafted fiber could be regenerated completely with almost equimolar diluted hydrochloric acid.

Macromolecularly imprinted calcium phosphate/polyacrylate/alginate (CP/PA/A) multi-hybrid polymer microspheres with the surface and embedded imprinting of bovine serum albumin were prepared with sodium alginate (SA), (NH4)2HPO4 and sodium polyacrylate (SPA) by using CaCl2 as gelling agent in inverse-phase suspension. Infrared spectrum analysis demonstrated that multihybrid components were produced in the microspheres. Rebinding dynamic of both imprinted microspheres proved a higher BSA rebinding relative to those nonimprinted ones. The specific surface area of CP/PA/A microspheres increased when compared with non-imprinted ones. The specific rebinding peak and imprinting efficiency cross point have appeared in rebinding dynamic curves, which showed remarkable difference in rebinding behaviours between surface and embedding imprinted microspheres.