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Synthesis and characterization of ion‐imprinted resin for selective removal of UO2(II) ions from aqueous medium
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In this work, uranyl ion-imprinted resin based on 2-(((4-hydroxyphenyl)amino)methyl)phenol was synthesized by
condensation polymerization of its uranyl complex in presence of resorcinol and formaldehyde cross-linkers Numerous
instrumental techniques including elemental analysis, Fourier transform infrared spectroscopy, ultraviolet, 1H
along with 13C nuclear magnetic resonance spectroscopy have been employed for complete characterization of
the synthesized ligand and its uranyl complex Additionally, the obtained ion-imprinted and non-imprinted resins
were investigated using scanning electron microscope and Fourier transform infrared spectroscopy The effects of
various essential parameters such as pH, temperature and contact time on removal of uranyl ions have been examined,
and the results indicated that the obtained resin exhibited the optimum activity at pH 5 Furthermore, the adsorption
process was spontaneous at all studied temperatures and followed the second-order kinetics model Also,
Langmuir adsorption isotherm exhibited the best fit with the experimental results with maximum adsorption capacity
1393 mg/g Moreover, the selectivity studies revealed that the ion-imprinted resin exhibited an obvious affinity
toward the uranyl ions in presence of other metal ions compared with the non-imprinted resin Copyright © 2015
John Wiley & Sons, Ltd
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PEO/PVDF Nanocomposites Preparation with Functionalized Single Walled Carbon Nanotube
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System of PEO/PVDF blend with functionalized single walled carbon nanotubes (SWCNTs-COOH) were prepared The enhanced material properties realized in conventional polymer nanocomposites using different techniques were discussed The results showed that SWNTs-COOH were covalently linked with the blend through OH and C-C bonds The intensities of some characteristic vibrational bands for those SWCNTS blends are decreased due to amorphous regions of the prepared samples The results data are augmented with increases of SWCNTS and the possibility of SWCNTs-COOH to be attached with OH group in the side chain of the polymeric matrices The interaction between SWCNTs and the blend results in decreasing crystallinity with rich amorphous phase The amorphous nature is responsible for higher conductivity The estimated values of the energy gap were increased due to charge transfer complexes Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) illustrated that SWNTs were well dispersed into the polymeric matrix and wrapped with polymer chains The properties of the blend were enhanced by the presence of SWNTs
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Synthesis and characterization of photo-crosslinkable4-styryl-pyridine modified alginate
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In this article photo-crosslinkablestyryl-pyridine modified alginate (ASP-Alg) was prepared and entirely investigated utilizing different instrumental techniques such as Elemental analysis, Fourier transform infrared (FTIR),13C and 1H nuclear magnetic resonance (NMR), ultraviolet-visible light (UV-vis), X-ray diffraction (XRD) spectra and scanning electron microscope (SEM)
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synthesis, characterization and biological evaluation of novel 1-N-Substituted Thiocarbomoyl-3- ferrocenyl-2-pyrazoline Derivatives
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System of PEO/PVDF blend with functionalized single walled carbon nanotubes (SWCNTs-COOH) were prepared The enhanced material properties realized in conventional polymer nanocomposites using different techniques were discussed The results showed that SWNTs-COOH were covalently linked with the blend through OH and C-C bonds The intensities of some characteristic vibrational bands for those SWCNTS blends are decreased due to amorphous regions of the prepared samples The results data are augmented with increases of SWCNTS and the possibility of SWCNTs-COOH to be attached with OH group in the side chain of the polymeric matrices The interaction between SWCNTs and the blend results in decreasing crystallinity with rich amorphous phase The amorphous nature is responsible for higher conductivity The estimated values of the energy gap were increased due to charge transfer complexes Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) illustrated that SWNTs were well dispersed into the polymeric matrix and wrapped with polymer chains The properties of the blend were enhanced by the presence of SWNTs
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Synthesis, characterization and biological evaluation of some novel nitrogen and sulphur containing organometallic heterocycles
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A series of some novel sulphur and nitrogen containing ferrocenyl linked heterocyclic
compounds were synthesized by multistep reactions and evaluated for in vitro antimicrobial activity
against 15 ATCC strains out of which 8 were bacterial (Pseudomonas aeruginosa, Streptococcus
bovis, Enterococcus faecalis, Klebsiella pneumoniae, Escherichia coli, Enterobacter cloacae,
Methicillin-resistant Staphylococcus aureus and Streptococcus mutans) and 7 were fungal
(Candida albicans, Candida dubliniensis, Candida glabrata, Candida parapsilosis, Candida tropicalis,
Candida kefyr and Candida krusei) strains The results clearly depict that the compounds (1–12) gave
an average antimicrobial activity against the tested strains with an exception of compound 12 which
stood out in terms of its activity against the tested organisms All these compounds gave a range of
MIC value between 32–64 lg/ml against S bovis, E coli and C tropicalis except compound 12
which gave a MIC of 16 lg/ml against each of them The MIC values of all these compounds
against biofilm forming P aeruginosa and S mutans were 64–256 lg/ml and 64–128 lg/ml
respectively which is apparently high, concluding that these compounds hold immense potential
to be employed as a two in one formulation of antibacterial as well as antifungal agents
ª 2015 The Authors Production and hosting by Elsevier BV on behalf of King Saud University This is
an open access article under theCCBY-NC-NDlicense
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Novel Pyrazoline‐based Organometallic Compounds Containing Ferrocenyl and Quinoline units: Synthesis, Characterization and Microbial susceptibilities
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Some novel pyrazoline‐based organometallic compounds were synthesized as
new leads in antimicrobial chemotherapy The structures of compounds were
elucidated by different spectroscopic techniques and elemental analyses All
compounds were investigated for in vitro antimicrobial studies against fifteen
ATTC bacterial and fungal strains The microbial susceptibility of these compounds
revealed that all the tested compounds gave good minimum inhibitory
concentration (MIC) values against the tested organisms that are either similar
or even better than the reference drugs amoxicillin and fluconazole, which gave
MIC values 8‐64 μg/ml against bacterial and 64 μg/ml against fungal strains,
respectively Among all compounds, compound (4d)
1‐(5‐(4‐chlorophenyl)‐3‐ferrocenyl‐4,5‐dihydropyrazol‐1‐yl)‐2‐quinolin‐8‐yloxy)
ethanone, emerged out the most promising antimicrobial organometallic derivative
with MIC values against all the strains ranging from 8‐32 μg/ml Other
compounds gave a range of MIC values between 16‐64 μg/ml against S bovis,
16‐32 μg/ml against E coli, and C tropicalis except compound (4d) which gave
MIC 8 μg/ml against S bovis and E coli, whereas 32 μg/ml against C tropicalis
Collectively, these compounds gave a lower MIC value between 32‐64 μg/ml
against both of the biofilm forming strains namely, P aeruginosa and S
mutans The results of microbial susceptibility concluded that these novel
organometallic compounds are new leads in antimicrobial chemotherapy and
can be very useful for further optimization work on microbial chemotherapy
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Chiral separation of (±)-methamphetamine racemate using molecularly imprinted sulfonic acid functionalized resin
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In the present study, a sulfonic acid functionalized enantio-selective resinous material was developed for effective chiral separation of (±)-methamphetamine racemate R-methamphetamine-sulfonamide phenolic derivative was first prepared and fully characterized utilizing instrumental and spectroscopic techniques
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Influence of hydroxyapatite nanoparticles on the properties of glass ionomer cement
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tGlass ionomer cement (GIC) is an important restorative dental biomaterial which is uti-lized in filling, lining and adhesion restoration The aim of this work is the enhancementof the mechanical, morphological, antibacterial and fluoride release properties of the glassionomer cement by incorporation of different wt% of nano hydroxyapatite powder (HA)The result of this work refers to that, the addition of nano-HA to GIC enhance its fluorideion release, compressive strength and antibacterial effect against Streptococcus mutans andthe bacterial inhibition zone reached to about 86 mm when 8% HA wt% is used This sug-gests that addition of nano-HA particles to GIC to produce GIC-HA hybrids which can beused as suitable materials for improving its fluoride ion release, mechanical properties andinhibiting residual bacteria in dentine© 2018 Brazilian Metallurgical, Materials and Mining Association Published by ElsevierEditora Ltda This is an open access article under the CC BY-NC-ND license(
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Preparation of photo-crosslinkable cinnamate modified hyaluronic acid for immobilization of horseradish peroxidase
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magnetic resonance (NMR) During the UV irradiation, the progress of the cross-linking reaction was monitored by the UV–vis light spectroscopy In addition, when the photo-induced cross-linking had accomplished, the morphological appearance of the hydrogel membrane was recorded using a scanning electron microscope (SEM)
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Synthesis and Characterization of Organo- Montmorillonite Clay and its Metal complexes for Polypropylene Clay Nano composites Applications
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1-acetylpyridinium Chloride-salicyolhydrazone (H2ACSH) was prepared from Salicylaldehyde and 1-acetylpyridinium
chloride hydrazide for using in modification of sodium montmorillonite clay in order to prepare organo - montmorillonite clay
(OMC) and its Zinc (OMC-Zn) and Zirconium (OMC-Zr) complexes in two different weight percentage (3 and 7 wt %)
Polypropylene /clay nanocomposites were prepared by melt intercalation technique using the prepared organo -
montmorillonite clay and its metal complexes The obtained nanocomposites were characterized by infrared absorption
spectroscopy (FTIR) and atomic force microscopy (AFM) to determine the morphology of obtained materials The thermal
behavior was evaluated from thermo gravimetric analysis (TGA) The combustion behavior of these intercalated ratios was
studied using cone calorimeter measurement to assess the PP/clay nanocomposites behavior during combustion The obtained
results indicate decreased flammability properties of PP/clay nanocomposites due to better char enhancement The new clay
provides an occasion for polymer / clay melt intercalation to obtain composites materials with important properties
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Nanocomposite Melt Spun PET fibers for Environmental Remediation
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POLYETHYLENE terphthalate /Montmorillonite clay nanocomposites were prepared after modification of Montmorillonite (MMT) clay using different concentration of Dimethyl di(hydrogenated tallow) ammonium chloride modifier The characterization of the prepared nanocomposites includes Fourier-transform infrared (FTIR), thermal gravimetric analysis (TGA) and scanning electron microscope (SEM) Fibers of pure polyethylene terphthalate (PET) and Polyethylene terphthalate/Montmorillonite clay nanocomposite (PET/MMT) were produced using melt spinning technique and the prepared fibers were characterized using thermal gravimetric in addition to SEM analysis The results show that the nanocomposite fibers have higher thermal stability than pure polyethylene terphthalate fibers in addition to high degree in homogeneity between PET and MMT clay in PET/MMT nanocomposite PET/MMT nanocomposite fiber with modified MMT 2% has been modified by grafting of MAA under variable conditions of monomer and initiator concentrations as well as grafting time and temperature The grafted fiber has been used in water treatment by removing of cationic dye under different conditions as pH values, and dye adsorption time
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Effect of thickness on structural and optical characteristics of Indium Phthalocyanine Chloride thin films for photodiode devices
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Indium phthalocyanine chloride, InPcCl, in the form of thin films were prepared
with different thicknesses by thermal evaporation technique X-ray diffraction
showed a hump at 2h = 28, which identified that the prepared InPcCl films
have an amorphous structure The particle size increased from 56 to 357 nm
with increased film thickness as indexed by Atomic Force Microscope technique
The transmittance and reflectance spectral distribution of InPcCl films
was measured through a range of 250–2500 nm of wavelength The optical
transition is indirectly allowed with two optical energy gaps (Eg1 = 137 eV and
Eg2 = 284 eV) for InPcCl thin films, which are smaller than other phthalocyanine
films The dispersion parameters were calculated for the different film thickness
of InPcCl films from refractive index analysis in the region of normal dispersion
The linear, third-order, non-linear refractive index and non-linear susceptibility
have also been measured The optical limiting response was evaluated for the
InPcCl films under the He–Ne laser and a green diode laser The InPcCl film of
thickness 95 nm exhibits the highest output power values and the normalized
power This advanced result will hopefully apply to the field of photodiode
devices in an industrial approach
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Amidoxime modified chitosan based ion-imprinted polymer for selective removal of uranyl ions
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Ion-imprinting strategy was utilized in the development of UO2(II) imprinted amidoxime modified chitosan
sorbent (U-AOCS) that can selectively remove UO2(II) from water First, cyanoactic acid was linked to the chitosan
–NH2 groups and then the inserted –CN groups were converted into amidoxime moieties, which chelate the
UO2(II) ions and then the polymer chains were cross-linked by glyoxal The UO2(II) ions have been then eluted
leaving their matching recognition sites The prepared U-AOCS along with the control NIP displayed maximum
capacities toward the UO2(II) ions around 332 and 186 mg/g, respectively, and the isotherms were interpreted
better by the Langmuir model in both adsorbents Moreover, the selective uptake of the uranyl ions in multi-ionic
aqueous solutions containing the tetravalent Th(IV) ions, trivalent Al(III), Eu(III), and Fe(III) ions, beside the
divalent Pb(II), Co(II), Ni(II), Cu(II) ions confirmed the successful creation of a considerable UO2(II) ions
selectivity in the U-AOCS construction In addition, the U-AOCS adsorbent displayed economic feasibility by
maintaining around 95 % of its initial efficiency after the regeneration and reuse for 5 adsorption/desorption
cycles
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Linear and nonlinear optical characteristics of manganese phthalocyanine chloride/polyacetate sheet: Towards flexible optoelectronic devices
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Thin films of manganese phthalocyanine chloride (MnPcCl) were prepared using a thermal deposition onto a
polyacetate sheet substrate The structure analyses of the obtained MnPcCl thin films of different thicknesses
ranging from 55 to 125 nm were investigated using the X-ray diffraction technique The transmittance and
reflectance of MnPcCl thin films were measured at the normal incident light in the 200–2500 nm wavelength
range The absorption coefficient analysis revealed that the films were characterized by indirect allowed transition
with two energy gaps The Wemple-DiDomenico single oscillator model explained the refractive index’s
dispersion behavior, and dispersion parameters were calculated The third-order nonlinear optical susceptibility
(χ(3)) and nonlinear refractive index (n2) were determined using Miller’s principles Optical limiting behavior
was estimated using the He–Ne (633 nm) and green (533 nm) lasers power The obtained results indicate that
MnPcCl films are excellent nonlinear optical materials for optical limiters
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Thiosemicarbazide-modified/ion-imprinted phenolic resin for selective uptake of cadmium ions
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Cd(II)-imprinted Cd(II) resin obtained from a thiosemicarbazide derivative of salicylic acid was prepared and
evaluated for selective uptake of Cd(II) ions In the beginning, the thiosemicarbazide derivative of salicylic acid
(H2TCS) was developed as a functional ligand that was then coordinated with Cd(II) ions to obtain the Cdcomplex
[CdTCS(H2O)3] After the full investigation of the ligand and its complex, they copolymerized with
resorcinol in presence of formalin, and the obtained resinous material was eluted with 01 M HNO3 solution to
extract the polymer incorporated Cd(II) ions and finally produce the Cd(II) ions selective Cd-RTCS sorbent The
maximum cadmium ions capacity by the Cd-RTCS reached 164 ± 1 mg/g, which could be a relatively high and
promising value Also, the adsorption isotherms were interpreted better with the Langmuir model In addition,
the Cd(II) sorption using Cd-RTCS was tested in a competitive medium of Pb(II), Ni(II), Zn(II), and, Cu(II) ions
and the results indicated a considerable selectivity toward the Cd(II) ions over the coexisted metals
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Synthesis of photo-crosslinkable hydrogel membranes for entrapment of lactase enzyme
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Polyvinyl alcohol (PVA) cinnamate ester derivative (PVCN) was prepared by partial esterification of PVA using
cinnamoyl chloride with various extents and then was examined using different instrumental and spectral
techniques that confirm the chemical structure of the photo-active product The obtained PVCN derivatives were
casted in membranes that were able to cross-link when exposed to a strong UV light via 2π + 2π cycloaddition
reaction, which was traced by UV–vis light spectra The textures of the obtained membranes were then observed
by SEM after freeze-drying to evaluate the effect of esterification degree on the cross-linking density The PVCN
membranes were also utilized as carrier support to immobilize the lactase enzyme by entrapment method and the
immobilized lactase kept around 76% of its activity and presented remarkable thermal stability and resistance
toward the environmental pH disturbances compared to the soluble lactase Moreover, the kinetic parameters
obtained from the kinetic experiments demonstrated an observed decrease in the vmax values from 4035 to
2762 U mg 1along with an increase in the Km values from 0203 to 0432 mM upon the lactase entrapment,
which implies a depressed affinity between the lactase and its substrate However, after 8 reuse cycles, the
entrapped lactase still maintained around 85% of its activity revealing promising economic feasibility of the
utilized entrapment technique
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