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The surfaces of Fe3 O 4 nanoparticles were modified with [3-(2,3 epoxypropoxy)propyl]trimethoxysilane and polyethylenimine (PEI) and then manganese acetate was loaded on Fe3 O 4@PEI and the resultant Fe3 O 4@PEI.Mn nanoparticles applied as a heterogeneous nanocatalyst. The prepared Fe3 O 4@PEI nanoparticles were characterized by FTIR, powder X-ray diffraction, TGA, VSM, SEM and TEM. The EDAX analysis was used to identify the elemental composition of the prepared Fe3 O 4@PEI.Mn nanoparticles. The catalytic activity and selectivity of the Fe3 O 4@PEI.Mn was examined in cyclohexene, ethyl benzene and toluene oxidation reaction with 30 % aqueous H2 O 2 as an oxidant. Furthermore, the effect of reaction parameters such as kinds of solvents, temperature, oxidant amount and catalyst reusability were investigated. Results show that the original properties of the nanoparticles were well preserved and also good activity and reusability were observed in the oxidation of cyclohexene, ethyl benzene and toluene. Moreover, this heterogeneous catalyst can be recovered with a magnetic field and reused for several times without noticeable loss of catalytic activity.

Pd-doped anatase TiO 2 nanoparticles were synthesized by a modified sol–gel deposition technique. The synthetic strategy is applicable to other transition and post-transition metals to obtain phase-pure anatase titania nanoparticles. This is important in the sense that anatase titania forms the most hydroxyl radicals (compared to other polymorphs like rutile, brookite, etc.) for better photocatalytic performance. XRD and Raman data confirm the phase-pure anatase formation. Doping of Pd 2+ into Ti 4+ sites (for substitutional doping) or interstitial sites (for interstitial doping) creates strain within the nanoparticles and is reflected in the XRD peak broadening and Raman peak shifts. This is because of the ionic radii difference between Ti 4+ (∼68 pm) and Pd 2+ (∼86 pm). XPS data confirm the formation of high surface titanol groups at the nanoparticle surface and a large number of loosely bound Ti 3+ –O bonds, both of which considerably enhance the photocatalytic activity of the doped nanoparticles. A comparative study with other metal doping (Ga) shows that TiO 2 : Pd nanoparticles have more Ti 3+ –O bonds, which enhance the charge transfer rate and hence improve the photocatalytic activity compared to other transition and post-transition metal-doped titania nanostructures.

Nanotechnology has opened up new opportunities for the design of nanoscale electronic devices suitable for developing high-performance biofuel cells. Glucose-based biofuel cells as green energy sources can be a powerful tool in the service of small-scale power source technology as it provides a latent potential to supply power for various implantable medical electronic devices. By using physiologically produced glucose as a fuel, the living battery can recharge for continuous production of electricity. This review article presents how nanoscience, engineering and medicine are combined to assist in the development of renewable glucose-based biofuel cell systems. Here, we review recent advances and applications in both abiotic and enzymatic glucose biofuel cells with emphasis on their “implantable” and “implanted” types. Also the challenges facing the design and application of glucose-based biofuel cells to convert them to promising replacement candidates for non-rechargeable lithium-ion batteries are discussed. Nanotechnology could make glucose-based biofuel cells cheaper, lighter and more efficient and hence it can be a part of the solutions to these challenges.

High-energy ultrasound irradiation has been used for the synthesis of a new copper(II) coordination supramolecular compound, [Cu2(μ-O2CCH3)2(μ-OOCCH3)(phen)2](BF4) (1), ("phen" is 1,10-phenanthroline) with nano-rods morphology. The new nano-structure was characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), FT-IR spectroscopy and elemental analyses. Compound 1 was structurally characterized by single crystal X-ray diffraction. The utilization of high intensity ultrasound has found as a facile, environmentally friendly, and versatile synthetic tool for the supramolecular coordination compounds.

Graphene quantum dots (GQDs), synthesised via controlled carbonisation of citric acid, were reduced by hydrazine hydrate and then used as hydrogen cyanide (HCN) gas sensors. Checking of the reduction step by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) techniques revealed that most of the oxygen-containing functional groups were removed from the GQDs. It was observed the reduction process is necessary for sensitising of GQDs for HCN gas. The electrical resistance of the reduced GQDs was increased as a result of their exposure to HCN gas. Accepting a p-type semiconducting characteristic for GQD material, the above-mentioned behaviour suggested electron donation from HCN to GQD. The sensor response to HCN gas was reversible, suggesting a reversible adsorption/desorption phenomenon of HCN to the GQDs. The response as well as the recovery time of the sensor was different depending on the HCN concentration tested. The developed sensor showed linear HCN resp...

The 1:1 imine intermediate generated by the addition of a primary amine to cyclohexanone trapped by N-isocyaniminotriphenylphosphorane (NICITPP) in the presence of aromatic carboxylic acids and the corresponding iminophosphorane intermediate was formed. Disubstituted 1,3,4-oxadiazole derivatives are formed via intramolecular aza-Wittig reaction of the iminophosphorane intermediate. The reactions were completed in neutral conditions at room temperature (18-26°C). The disubstituted 1,3,4-oxadiazole derivatives were produced in excellent yields.

A novel nano-cauliflower-shaped lead(II) metal-organic coordination polymer, [Pb(mu-2-pinh)N-3 H2O](n) (1), was synthesized using an ultrasonic method. The nanostructure was characterized by scanning electron microscopy (SEM), X-ray powder diffraction, IR spectroscopy, elemental analysis, and thermal analysis. The compound was structurally characterized by single-crystal X-ray diffraction. The coordination compound takes the form of a zig-zag one-dimensional polymer in solid state. The coordination number of the lead(II) ions is six (PbN4O2) with three nitrogen atoms and one oxygen atom from two linker organic ligands, as well as one oxygen from coordinated water and one nitrogen atom from terminal coordinated azide anion. It has a stereo-chemically active lone electron pair, and the coordination sphere is hemidirected. The zig-zag 1D chains interact with neighbouring chains through weak interactions, creating a 3D supramolecular metal-organic framework. Lead oxide nanoparticles were obtained by thermolysis of the new nano coordination compound at 180 A degrees C with oleic acid as a surfactant. The morphology and size were further studied using SEM. Natural bond orbital analyses demonstrate the electronic properties of the lead centre and other atoms. University of Qom National Research Foundation of Korea - NRF-2015-002423 Polish Ministry of Science and Higher Education for the Faculty of Chemistry of Wroclaw University of Technology

We report the fabrication of self-organized titania (TiO2) nanotubes (TNTs) with controlled pore diameters (140–20 nm) by anodization for the application of electrochemical capacitor electrodes. The areal capacitances obtained for 140 nm TNTs as 0.23/0.13 mF cm–2 at a scan rate of 1/5 mV s–1 and it is enhanced to 5.5/2.9 mF cm–2 (at the same scan rates) by controlling the pore diameter to 20 nm. In this study, role of pore diameter in the capacitance behavior of TNTs is explained on the basis of effective surface area and presence of oxygen vacancies/titanium interstitials. With a decrease in the pore diameter, the surface area-to-volume ratio (and hence, active surface sites) increases, which leads to greater dissociation of Ti4+ into Ti3+ under high temperature annealing and thus brings more nonstoichiometric defects like Ti3+ interstitials and oxygen deficiency within the lower dimensional TNTs. This manifests higher charge conductivity and greater electrochemical performance of TNTs with lower diamete...

A novel chemiluminescence (CL) system is introduced based on the oxidation of carminic acid by KMnO4 in acidic conditions. CdS quantum dots (QDs) were synthesized using a facile hydrothermal method which efficiently enhanced the intensity of the CL system. A possible mechanism for the proposed system is presented using the kinetic curves, CL spectra, photoluminescence (PL), and ultraviolet-visible (UV-Vis) analysis. The emission intensity of the KMnO4-carminic acid-CdS QDs system was quenched in the presence of a trace level of cloxacillin. Based on this quenching effect, a novel and sensitive flow injection CL method was developed for determining cloxacillin concentrations. At optimal experimental conditions, the decreased CL intensity had a good linear relation with the cloxacillin concentration in the range of 0.008 to 22.0 mg L(-1). The detection limit (3σ) was 5.8 µg L(-1). The precision of the method was calculated by analyzing samples containing 4.0 mg L(-1) of cloxacillin (n=11), and the relative standard deviations (RSD%) were 2.08%. The feasibility of the method is also demonstrated for determining cloxacillin concentrations in environmental water samples and a pharmaceutical formulation.

We prepared pure and samarium-doped ZnS (SmxZn1−xS1+0.5x) nanoparticles via hydrothermal process at 160 °C for 24 h. XRD analysis shows that the particles were well crystallized and corresponds to a cubic sphalerite phase. SEM and TEM images indicate that the sizes of the particles were in the range of 20–60 nm. The photocatalytic activity of Sm-doped ZnS nanoparticles was evaluated by monitoring the decolorization of Reactive Red 43 in aqueous solution under visible light irradiation. The color removal efficiency of Sm0.04Zn0.96S and pure ZnS was 95.1% and 28.7% after 120 min of treatment, respectively. Among the different amounts of dopant agent used, 4% Sm-doped ZnS nanoparticles indicated the highest decolorization. We found that the presence of inorganic ions such as Cl−, CO32− and other radical scavengers such as buthanol and isopropyl alcohol reduced the decolorization efficiency.

Terbium-doped cadmium sulfide nanoparticles with different terbium contents were successfully synthesized via sonochemical route. The prepared samples were characterized by X-ray diffraction, scanning electron microscopy, photoelectron X-ray spectroscopy, and UV–Vis diffuse reflectance spectroscopy techniques. The as-prepared nanocatalyst were used for sonocatalytic degradation of Methylene Blue. Among the different amounts of dopant, 8 % Tb-doped CdS showed the highest sonocatalytic activity. The order of inhibitory effect of radical scavengers was 1, 4 Benzoquinone > SO3 2− > CO2 3−> I−. The effects of various parameters such as initial dye concentration, catalyst loading, ultrasonic power, and the presence of radical scavengers were investigated.

A convenient one-pot synthesis of chromene derivatives from the three-component reaction of triphenylphosphine and dialkyl acetylenedicarboxylate and 2-hydroxybenzaldehyde derivatives in the presen...

Pure and Sm-doped ZnO nanoparticles were synthesized applying a simple sonochemical method. The nanocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) techniques which confirmed the successful synthesis of the doped sonocatalyst. The sonocatalytic degradation of Acid Blue 92 (AB92), a model azo dye, was more than that with sonolysis alone. The 6% Sm-doped ZnO nanoparticles had a band gap of 2.8 eV and demonstrated the highest activity. The degradation efficiency (DE%) of sonolysis and sonocatalysis with undoped ZnO and 6% Sm-doped ZnO was 45.73%, 63.9%, and 90.10%, after 150 min of treatment, respectively. Sonocatalytic degradation of AB92 is enhanced with increasing the dopant amount and catalyst dosage and with decreasing the initial AB29 concentration. DE% declines with the addition of radical scavengers such as chloride, carbonate, sulfate, and tert-butanol. However, the addition of enhancers including potassium periodates, peroxydisulfate, and hydrogen peroxide improves DE% by producing more free radicals. The results show adequate reusability of the doped sonocatalyst. Degradation intermediates were recognized by gas chromatography-mass spectrometry (GC-MS). Using nonlinear regression analysis, an empirical kinetic model was developed to estimate the pseudo-first-order constants (kapp) as a function of the main operational parameters, including the initial dye concentration, sonocatalyst dosage, and ultrasonic power.

A sensitive, rapid and simple flow-injection chemiluminescence (CL) system based on the light emitted from KMnO4-cadmium sulfide quantum dots (CdS QDs) reaction in the presence of cetyltrimethylammonium bromide (CTAB) in acidic medium was developed as a CL probe for the sensitive determination of atenolol. Optical and structural features of CdS QDs capped with l-cysteine, which synthesized via hydrothermal approach, were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), and UV-Vis spectroscopy. The CL intensity of KMnO4-CdS QDs-CTAB was remarkably enhanced in the presence of trace level of atenolol. Under optimum experimental conditions, there is a linear relationship between the increase in CL intensity of KMnO4-CdS QDs-CTAB system and atenolol concentration in a range of 0.001 to 4.0 mg L(-1) and 4.0 to 18.0 mg L(-1), with a detection limit (3σ) of 0.0010 mg L(-1). A possible mechanism for KMnO4-CdS QDs-CTAB-atenolol CL reaction is proposed. To prove the practical application of the KMnO4-CdS QDs-CTAB CL method, the method was applied for the determination of atenolol in spiked environmental water samples and commercial pharmaceutical formulation. Furthermore, corona discharge ionization ion mobility spectrometry (CD-IMS) technique was utilized for determination of atenolol.

The sonochemically synthesized Ho-doped ZnO nanoparticles were characterized by XRD, SEM, TEM, and XPS techniques. The sonocatalytic degradation of Reactive Orange 29 (RO29) was greater than that with sonolysis alone. DE% declines with the addition of chloride, carbonate, sulfate, and tert-butanol as radical scavengers. Addition of potassium periodate, peroxydisulfate, and hydrogen peroxide as enhancers improves DE%. The results demonstrate proper reusability of the doped sonocatalyst. Degradation intermediates were identified by gas chromatography–mass spectrometry (GC–MS). Using nonlinear regression analysis, an empirical kinetic model was developed to predict the pseudo-first-order constants (kapp) as a function of the operational parameters.

Molecular dynamics simulations were performed to investigate the separation of copper and mercury ions as heavy metals from aqueous solution through the functionalized pore of a boron nitride nanosheet (BNNS) membrane. The considered system was comprised of a BNNS with a functionalized pore located in the centre of a simulation box containing an aqueous ionic solution of copper chloride and mercuric chloride. An external voltage was applied along the simulated system in order to produce a separation of heavy metals using pore of BNNS. A functionalized pore of BNNS was obtained by passivating each nitrogen and boron atoms at the pore edge with a fluorine and hydrogen atom, respectively. Our results show that the voltage caused the Cu2+ and Hg2+ cations to pass selectively through the functionalized pore of the BNNS. This selective behaviour of the BNNS is due to the potential of the mean force of each ion. The potential of the mean force of the heavy metals shows that the heavy metals ions met an energy barrier and could not pass through the functionalized pores of the BNNS. By applying a voltage to the system, they overcame the energy barrier and crossed the pores. We calculated the radial distribution function of ion-water and its integrations; the ion retention time; the hydrogen bond; and the autocorrelation function of the hydrogen bond. Using these parameters, the structure of the water molecules and ions were investigated in the system.

Undoped and doped PbTe nanoparticles with neodymium (Nd) and ytterbium (Yb) ions were hydrothermally synthesized and deposited on anodized TiO2 nanotube (TNT) arrays to form hybrid binder-free TNT electrodes for supercapacitor. The as-prepared TNT electrodes were characterized by XRD, SEM, and XPS. Besides, BET method was used to confirm the surface area of as-synthesized nanoparticles. Among TNT electrodes, the one with Yb-doped PbTe exhibited enhanced capacitance (0.93 mF/cm2 at 10 mV/s, 2.16 mF/cm2 at 5 µA/cm2) and low resistance (4.68 Ω), along with good stability (~93%). Overall, TNT in combination with Yb-doped PbTe nanoparticles could provide an ideal platform for efficient delivery of capacitance.

The nanorods of a new Pb(II)-chloride metal-organic coordination polymer, [Pb2Cl2Q2]n(1)(HQ= 8-hydroxyquinoline) was synthesized using the sonochemical synthesis. The characteristics of the compound were determined via the elemental analysis, single-crystal X-ray analysis, scanning electron microscopy (SEM), IR spectroscopy, and powder X-ray diffraction (PXRD). The X-ray structure indicated that the compound included a 2-dimensional polymer in the solid-state with two different centers of Pb(II). Two coordination numbers (6 and 7) with two coordination spheres (symmetrical and unsymmetrical) were observed for the lead (II) centers. The structure showed a self-assembly capability with several weak interactions, such as H-bonds and π–π interactions. Sonochemical results showed the uniform, rod-like morphology of the title compound. The computational DFT results demonstrated that the HOMO (highest occupied molecular orbital) was confined primarily between one Cl– anion and Pb centers, whereas the LUMO (lowest unoccupied molecular orbital) was roughly delocalized on the Q− ligand N and O atoms comprising the other Cl– anions. The estimated gap of HOMO–LUMO was 3.708 eV and the composite was highly shock-sensitive. The α-PbO nanostructures were produced by thermolysis of 1 at 180 °C via oleic acid as a surfactant.

We prepared novel Raman substrates for the sensitive detection of submicron-sized plastic spheres in water. Anisotropic nanostar dimer-embedded nanopore substrates were prepared for the efficient identification of submicron-sized plastic spheres by providing internal hot spots of electromagnetic field enhancements at the tips of nanoparticles. Silver-coated gold nanostars (AuNSs@Ag) were inserted into anodized aluminum oxide (AAO) nanopores for enhanced microplastic (MP) detection. We found that surface-enhanced Raman scattering (SERS) substrates of AuNSs@Ag@AAO yielded stronger signals at the same weight percentages for polystyrene MP particles with diameters as small as 0.4 μm, whereas such behaviors could not be observed for larger MPs (diameters of 0.8 μm, 2.3 μm, and 4.8 μm). The detection limit of the submicrometer-sized 0.4 μm in our Raman measurements were estimated to be 0.005% (∼0.05 mg/g =50 ppm) along with a fast detection time of only a few min without any sample pretreatments. Our nano-sized dimensional matching substrates may provide a useful tool for the application of SERS substrates for submicrometer MP pollutants in water.

In this research, efficient and novel catalysts based on hierarchical carbon nanohorns-titanium nanoflowers have been prepared by one-pot solvothermal process. Hydrogen generation from dye-contaminated water and dye degradation along with electrochemical supercapacitance performance have been investigated using the synthesized hierarchical catalyst to produce 4500 μmol g−1 h−1 of hydrogen from the photocatalytically generated aqueous methylene blue and methyl orange dyes, which were degraded up to 90% under natural solar light irradiation. These results offer a new path to generate hydrogen from the aqueous dyes. The catalysts electrode showed 164.6 F g−1 supercapacitance at 5 mV s−1 scan rate, which is nearly 1.3 and 1.65-times higher than that of pristine titanium nanoflower and carbon nanohorns electrodes, respectively. Such superior results were achieved due to good crystallinity, improved optical absorption strength, strong chemical composition between the two components, and hierarchical morphology as demonstrated from XRD, UV-DRS, TEM, XPS, and Raman spectral characterizations.

The undoped and indium doped SnSe (In-SnSe) thin films were successfully prepared by the two-stage process (sputtering and rapid thermal annealing process). The physical properties of the prepared thin films were investigated. Crystallographic patterns of the undoped and doped SnSe thin films showed the single-phase orthorhombic-SnSe. The diffraction peaks slightly shifted towards the higher diffraction angles as well as Raman peaks also shifted towards higher Raman shift by doping of indium. Morphology of the In-SnSe films changed significantly by changing the indium percentage. The optical bandgap of SnSe and In-SnSe films was varied in between 1.06 eV and 1.50 eV, and the electrical properties of In-SnSe films were significantly changed with dopant concentration. The obtained physical properties of In-SnSe thin films are suitable for solar cell device fabrication.

Herein, TiO2 nanoparticles were immobilized on the ceramic surface using the sol-gel dip-coating method, which confirmed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Then, a semi-batch reactor containing the prepared ceramic plates, which irradiated by the various UV lights was used for the degradation of the albendazole (ALZ) and metronidazole (MTZ) pharmaceuticals by the photocatalytic ozonation process. The control experiments were performed to compare the photocatalysis, ozonation, photo-ozonation and photocatalytic ozonation processes under the same operational conditions with the UV-A, UV-B and UV-C irradiations. The synergistic effect of photocatalysis and ozonation was observed; moreover, the results revealed that the UV-A/TiO2/O3 had the highest efficiency for the ALZ and MTZ degradation owing to the synergistic heterogeneous reactions (SHRs), which led to more reactive oxygen species (ROS). The MTZ and ALZ degradation were probed by monitoring the dissolved ozone, oxygen and hydrogen peroxide concentrations during the various processes including the UV-A/TiO2/O3 process. The obtained results disclose that the ALZ degradation is lower than the MTZ due to its resistant nature with more direct attacks of the ozone in the bulk solution compared to the MTZ. Furthermore, the various compounds as the holes (h+) and ROS scavengers or ozone solubility enhancers were added to the reaction bulk to investigate the exact mechanism of the photocatalytic-ozonation. Eventually, the degradation intermediates of the pharmaceuticals generated in the photocatalytic-ozonation process were successfully recognized by the Gas chromatography-mass spectrometry (GC-MS) and the possible degradation paths were suggested for the degradation of pollutants considering the responsible ROS in each case.

Cu2SnSe3 thin films were prepared by the two-stage process (metal layers deposited by direct current-sputtering + selenization of metal layers by rapid thermal annealing). The effect of selenization temperature (350 °C-550 °C) on the physical properties of Cu2SnSe3 was investigated thoroughly. The formation of single-phase Cu2SnSe3 was confirmed by the X-ray diffraction patterns of the selenized films at 550 °C. The Raman modes at 181 cm−1 and 231 cm−1 confirmed the formation of single-phase Cu2SnSe3 at 550 °C and the presence of secondary phase identification was also investigated. The compositional and morphological analysis was investigated using energy-dispersive X-ray spectrometer and field emission scanning electron microscopy measurements, respectively. The optical properties of selenized films were measured by the ultraviolet-visible spectroscopy and the calculated results showed the bandgap values in the range 0.9-1.44 eV. The Hall Effect measurement showed that the values of carrier concentration were decreased and the resistivity was increased with increasing of selenization temperature.

In this study, the electrocoagulation of perfluorooctanoic acid (PFOA) in water using an iron (Fe) electrode was investigated. The effects of the current density, stirring speed, and electrolyte concentration (NaCl) on the corresponding removal rates of PFOA were examined. An increase in the current density from 2.4 to 80.0 mA cm−2 led to a significant increase in the removal efficiency of PFOA from 10.0 to 100.0% within 6 h. Formate (HCOO−) ions and three shorter-chain perfluorocarboxylates (i.e., perfluoropentanoic acid; PFPeA, perfluorohexanoic acid; PFHxA, and perfluoroheptanoic acid; PFHpA) were observed as organic byproducts during the electrocoagulation of PFOA, indicating that the C-C bond between C7F15 was first broken down and then was degraded into short carbon-chain compounds by PFOA decomposition. 65% of fluorine recovery as fluoride ions and organic fluorine in shorter-chain byproducts (PFPeA, PFHxA, and PFHpA) with 60% of total organic carbon (TOC) removal was achieved within 6 h during electrocoagulation, while the complete removal of PFOA was achieved. Our results imply that electrocoagulation using Fe electrode can effectively degrade PFOA into shorter-chain byproducts with significant mineralization.

Engineered metal-oxide nanoparticles have greatly been used in various bio-applications, but their physicochemical properties change dramatically within a bio-system. Therefore, the development of new metal-oxide nanoparticles and proper understanding of their toxicity profile in bio-environment are very important for advancement of cancer-related diagnostic and therapeutic approaches. Nanostructured wide-bandgap semiconductors ZnSn(OH)6 and Zn2SnO4 are fabricated by one-pot hydrothermal synthesis and tested for the first time in anti-cancer treatments. The crystalline zinc-hydroxystannate is converted by high-temperature annealing into amorphous and then crystalline zinc-orthostannate, as confirmed by Rietveld refinement analyses. A dose-dependent cytotoxicity is observed when human cervical carcinoma cell lines are exposed to these nanomaterials, mainly due to the elevation of intracellular reactive-oxygen-species levels in the treated cells, which leads to oxidative stress and cell damage. The crystalline phases of the nanomaterials reveal better cell-killing efficacy due to the overlap of the conduction-band energy levels with the cellular redox potential, leading to favorable electron transfer from the biological redox couples to the conduction-band of the semiconductor nanoparticles, thus producing more reactive-oxygen-species for cell damage. Importantly, this higher reactive-oxygen-species production by the crystalline samples significantly reduces cancer cell migration and proliferation and decreases metastasis, which remains an unmet challenge in cancer therapy.

A wide range of heterogeneous catalysts has been used for degradation of dyes through various techniques, albeit, little is recognized about the productive activation of hydrogen peroxide (HP), persulfate (PS), and ozone over heterogeneous catalysts and under UV light irradiation. In this research, Cr and Ce were placed within the magnetite structure and the resultant nanoparticles were characterized by XRD, SEM, HRTEM, EDX, BET, VSM, DRS, XPS, and FT-IR analyses. The synthesized magnetic nanoparticles were used in a series of photocatalytic processes for the degradation of methylene blue dye (MBD) as a probe molecule. The Fe2.5Cr0.2Ce0.3O4 sample showed great performance in comparison with the other samples. The highest activity of Fe2.5Cr0.2Ce0.3O4 sample was described based on its ability to effectively actuate HP, PS, and ozone under UV light irradiation. The outcomes of the studied systems: catalyst, UV, and UV-catalyst alone and along with oxidants were well illustrated in contrast to one another. In this regard, the effects of HP and PS concentrations and ozone inlet flow rate were evaluated. The results postulated that the ozone-based systems had eminent efficiency in the degradation of MBD. In each process, the reusability of the Fe2.5Cr0.2Ce0.3O4 sample was studied and the superior stability of the catalyst was inferred. The mineralization efficacy of MBD was appraised by total organic carbon (TOC) and the order of TOC removal capacity was found as UV-catalyst-PS > UV-catalyst-ozone > UV-catalyst-HP. Eventually, GC–MS analysis of the oxidized samples confirmed the formation of 8 intermediates by the UV-catalyst-ozone system.

The main prerequisite of an active visible-light-driven photocatalyst is to effectively utilize the visible light to induce electron-hole (e

The aim of present study was to develop the novel methods for chemical and physical modification of superparamagnetic iron oxide nanoparticles (SPIONs) with polymers via covalent bonding entrapment. These modified SPIONs were used for encapsulation of anticancer drug doxorubicin. At first approach silane–grafted magnetic nanoparticles was prepared and used as a template for polymerization of the N-isopropylacrylamide (NIPAAm) and methacrylic acid (MAA) via radical polymerization. This temperature/pH-sensitive copolymer was used for preparation of DOX–loaded magnetic nanocomposites. At second approach Vinyltriethoxysilane-grafted magnetic nanoparticles were used as a template to polymerize PNIPAAm-MAA in 1, 4 dioxan and methylene-bis-acrylamide (BIS) was used as a cross-linking agent. Chemical composition and magnetic properties of Dox–loaded magnetic hydrogel nanocomposites were analyzed by FT-IR, XRD, and VSM. The results demonstrate the feasibility of drug encapsulation of the magnetic nanoparticles with NIPAAm–MAA copolymer via covalent bonding. The key factors for the successful prepardtion of magnetic nanocomposites were the structure of copolymer (linear or cross-linked), concentration of copolymer and concentration of drug. The influence of pH and temperature on the release profile of doxorubicin was examined. The in vitro cytotoxicity test (MTT assay) of both magnetic DOx–loaded nanoparticles was examined. The in vitro tests showed that these systems are no toxicity and are biocompatible. IC50 of DOx–loaded Fe3O4 nanoparticles on A549 lung cancer cell line showed that systems could be useful in treatment of lung cancer.

Biowaste, derived from cooking-oven-produced carbon nanoparticles (WCP), are incorporated into polyaniline (PANI) via in-situ chemical oxidative polymerization to achieve excellent electrochemical properties for application in supercapacitors. The WCP-PANI composite electrodes have shown high-performance charge storage, due to combinatorial effect of electrical double layer capacitance from WCP and pseudocapacitance from PANI. With increase in the WCP percolation, work function of PANI is increased, which improves the charge-trapping capabilities of composites. For such distinct charge-trapping mechanism, areal capacitance of the composite microelectrode remains near-constant with increase in scan rate or current density. This indicates the suppression of diffusion limitations at higher scan rates to considerably enhance the rate capability. Also, with increasing polymerization time, strong interaction in this conjugated system greatly improves the charge-transfer reaction between PANI and WCP. The areal capacitance of the composite electrode is found to increase more than 600 times over pure PANI electrode. Moreover, energy-power performance of the microelectrode reveals almost 550% increment in the power density with a mere 1% decrement in energy density. Such rationally synthesized WCP-PANI composite electrodes using biowaste carbon nanomaterials, provide opportunities for the development of next-generation green-supercapacitors with improved energy storage performance. proof published

A transient continuum model of the ODEP chip containing single circular particle inside is constructed based on multi-physical field coupling. The dielectrophoresis force and liquid viscous resistance acting on particle are calculated by employing the full Maxwell stress tensor. The coupled flow field, electric field and particle are solved by the arbitrary Lagrange–Euler (ALE) method simultaneously. The throughout dynamic process of particle in the ODEP chip is demonstrated, and the effect of several critical parameters on particle electrodynamics is illuminated. The additional disturbing effect of the photoconductive layer on the electric field as well as the micro-channel wall on the flow field is presented to clarify the particle motion in the vertical direction. The results in this study provide a detailed understanding of the particle dynamics in the ODEP chip.

Tetramethylguanidine-functionalized silica-coated iron oxide magnetic nanoparticles as a productive and reusable catalyst have been applied for the one-pot three-component synthesis of furanone derivatives (4a–o). In addition to the characterization of all products by FT-IR, $$^{1}\hbox {HNMR}$$ and $$^{13}\hbox {CNMR}$$ spectroscopy, single-crystal X-ray analysis of ethyl 5-oxo-2-phenyl-4-(phenylamino)-2,5-dihydrofuran-3-carboxylate product has been made. Easy recrystallization and good-to-excellent yields (81–92%) of furanone derivatives are notable characteristics of this procedure. The catalyst identification was performed using FT-IR, XRD, SEM, TEM and TGA techniques. It is worth noting that the nanocatalyst can be recycled with an external magnet and reused for several times. SYNOPSIS In this procedure, tetramethylguanidine-functionalized silica-coated iron oxide magnetic nanoparticles $$(\hbox {Fe}_{3}\hbox {O}_{4}\hbox {-TMG})$$ has been employed as an efficient, eco-friendly and reusable catalyst for one-pot three-component synthesis of furanone derivatives in a green solvent at $$40\,^{\circ }\hbox {C}$$ . The use of magnetic nanocatalyst is the superior feature of this method.

Human head and body lice attach their eggs respectively to human hair or clothing by female lice secreted glue that hardens into a nit sheath that protects the egg. In this study, a series of experiments were conducted to characterize the glue-like material of the nit sheath. Fourier transform infrared spectroscopy on embryo-cleared nit showed proteinaceous amide I bands. With this result, we determined the amino acid composition of the nit sheath proteins and performed similarity search against the protein products of the body louse genome to identify the candidate nit sheath proteins. The identified two homologous proteins newly named as louse nit sheath protein (LNSP) 1 and LNSP2 are composed of three domains of characteristic repeating sequences. The N-terminal and middle domains consist of tandem two-residue repeats of Gln-Ala and Gly-Ala, respectively, which are expected to fold into β-strands and may further stack into β-sheets, whereas the C-terminal domain contains multiple consecutive Gln residues. Temporal and spatial transcription profiling demonstrated that both LNSP1 and LNSP2 are most predominantly expressed in the accessory gland of females of egg-laying stage, supporting that they indeed encode the nit sheath proteins. Further adhesive property of recombinant partial LNSP1 suggests that both LNSP1 and LNSP2 may act as glues.

The dielectrophoretic (DEP) choking phenomenon is revisited for Janus particles that are transported electrokinetically through a microchannel constriction by a direct-current (DC) electric field. The negative DEP force that would block a particle with a diameter significantly smaller than that of the constriction at its inlet is seen to be relaxed by the rotation of the Janus particle in a direction that minimizes the magnitude of the DEP force. This allows the particle to pass through the constriction completely. An arbitrary Lagrangian-Eulerian (ALE) numerical method is used to solve the nonlinearly coupled electric field, flow field, and moving particle, and the DEP force is calculated by the Maxwell stress tensor (MST) method. The results show how Janus particles with non-uniform surface potentials overcome the DEP force and present new conditions for the DEP choking by a parametric study. Particle transportation through microchannel constrictions is ubiquitous, and particle surface properties are more likely to be non-uniform than not in practical applications. This study provides new insights of importance for non-uniform particles transported electrokinetically in a microdevice.

Viscoelastic solution is encountered extensively in microfluidics. In this work, the particle movement of the viscoelastic flow in the contraction–expansion channel is demonstrated. The fluid is described by the Oldroyd-B model, and the particle is driven by dielectrophoretic (DEP) forces induced by the applied electric field. A time-dependent multiphysics numerical model with the thin electric double layer (EDL) assumption was developed, in which the Oldroyd-B viscoelastic fluid flow field, the electric field, and the movement of finite-size particles are solved simultaneously by an arbitrary Lagrangian–Eulerian (ALE) numerical method. By the numerically validated ALE method, the trajectories of particle with different sizes were obtained for the fluid with the Weissenberg number (Wi) of 1 and 0, which can be regarded as the Newtonian fluid. The trajectory in the Oldroyd-B flow with Wi = 1 is compared with that in the Newtonian fluid. Also, trajectories for different particles with different particle sizes moving in the flow with Wi = 1 are compared, which proves that the contraction–expansion channel can also be used for particle separation in the viscoelastic flow. The above results for this work provide the physical insight into the particle movement in the flow of viscous and elastic features.

Reactions of N-isocyaniminotriphenylphosphorane (NICITPP) with 2-oxopropyl-1-benzenecarbothioate in the presence of aromatic carboxylic acids and primary amines proceed smoothly at room temperature...

Pr-doped ZnS nanoparticles with variable praseodymium contents were successfully synthesized via a hydrothermal process. The products were characterized by XRD, SEM, TEM, XPS, TGA and UV–vis techniques. The photocatalytic performance of the as-synthesized nanoparticles was investigated for the decolorization of Reactive Blue 19 solution under visible light irradiation. The highest decolorization was achieved with 3% Pr-doped ZnS nanoparticles. The order of inhibitory effect of radical scavengers was butanol > Cl− > CO32− > isopropyl alcohol. The Langmuir–Hinshelwood (L-H) adsorption and rate coefficients for the photocatalytic process were successfully established.

Water was used as an efficient green solvent for the synthesis of sterically congested 1,3,4-oxadiazoles derivatives via a one-pot, three-component reaction of various aromatic carboxylic acids, ac...

A simple and sensitive flow injection chemiluminescence (CL) method was developed for determination of nalidixic acid by application of CdS quantum dots (QDs) in KMnO4-morin CL system in acidic medium. Optical and structural features of L-cysteine capped CdS quantum dots which were synthesized via hydrothermal approach were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL), and ultraviolet-visible (UV-Vis) spectroscopy. Moreover, the potential mechanism of the proposed CL method was described using the results of the kinetic curves of CL systems, the spectra of CL, PL and UV-Vis analyses. The CL intensity of the KMnO4-morin-CdS QDs system was considerably increased in the presence of nalidixic acid. Under the optimum condition, the enhanced CL intensity was linearly proportional to the concentration of nalidixic acid in the range of 0.0013 to 21.0 mg L(-1), with a detection limit of (3σ) 0.003 mg L(-1). Also, the proposed CL method was utilized for determination of nalidixic acid in environmental water samples, and commercial pharmaceutical formulation to approve its applicability. Furthermore, corona discharge ionization ion mobility spectrometry (CD-IMS) method was utilized for determination of nalidixic acid and the results of real sample analysis by two proposed methods were compared. Comparison the analytical features of these methods represented that the proposed CL method is preferable to CD-IMS method for determination of nalidixic acid due to its high sensitivity and precision.

Nano-structures of a new discrete coordination compound of divalent cobalt with the pyrazol (pzH) containing the terminal isothiocyanate anions, [Co(pzH)2(NCS)2] (1), with discrete molecular architecture in solid state was synthesized by a sonochemical method. The new nanostructure was characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray powder diffraction, IR, and elemental analysis. The supramolecular features in these complexes are guided and controlled by weak directional intermolecular interactions. The discrete molecules interact with each other through labile interactions creating a 3D supramolecular framework. The CoO nanoparticles were obtained by thermolysis of 1 at 180 °C with oleic acid as a surfactant.

Purpose – This paper aims to study the Improvements in self-cleaning property of the white acrylic water-based paint by addition of different percentages of three commercially available titanium dioxide (TiO2) nanoparticles as additives. Then, due to the risk of destruction of polymeric materials in the presence of nanoparticles, degradation of dry paint film samples was investigated for 15 days using two important chalking and yellowing factors. Finally, the TiO2-modified paint sample with the best performance and optimum percentage of TiO2 nanoparticles that produced desired self-cleaning and dry film properties was introduced. Design/methodology/approach – Self-cleaning and dry film properties of white acrylic water-based paint were investigated by addition of three various types of commercial available TiO2 nanoparticles (SSP-25, STA-100 and KA-100). X-ray diffraction, transmission electron microscopy and Brunauer–Emmett–Teller were used for characterization of TiO2 samples. Colorimetric tests in decolourization of C.I. Basic Red 46 (BR46) were used for determination of self-cleaning properties of TiO2-modified paints in comparison with unmodified paint sample. Also, paints defects such as chalking and yellowing were tested along two weeks. Findings – The results indicated that, in all types of TiO2 nanoparticles, by increasing the amount of TiO2 in modified paint, self-cleaning property of the samples was enhanced. The paint containing SSP-25 indicated better self-cleaning properties than others due to its larger surface area. However, its usage above 3.5 weight per cent caused yellowing and chalking defects in dried paint film. Practical implications – In this research, TiO2-modified paint sample with the best performance in both self-cleaning and mechanical properties was selected among the nine sets of prepared paint samples. All the materials used in this research such as acrylic resin and three types of TiO2 nanoparticles are of industrial grade. Therefore, the introduced TiO2-modified paint sample has the potential for the commercial production as a building exterior paint. Originality/value – In the present study, an attempt at introducing a self-cleaning paint sample with acceptable mechanical properties using three types of commercially available TiO2 nanoparticles as additives and industrial grade of acrylic resin which is the most commonly used water-based resin in building paints, as binder. As far as it was searched in the literatures, the parallel study of the self-cleaning and mechanical properties of paints has not been reported as noteworthy. Self-cleaning property of the acrylic water-based paint samples was investigated by adding three types of the commercially available TiO2 nanoparticles. Also considering the possible detrimental effects of TiO2 nanoparticles on polymeric materials and consequently on physical properties of the paint, chalking and yellowing factors in dried paint samples were evaluated.

Titania nanotubes (TNTs) synthesized by an anodization process were used as a basic substrate material to create different morphologies of quasi-1D (nanoribbons), 2D (nanoflakes), and 3D (nanoparticles) structures via an alkali-controlled hydrothermal route. Graphite oxide was introduced to the hydrothermal unit to fabricate graphene oxide/reduced graphene oxide–titania nanostructure hybrid materials. The presence of NaOH and graphene oxide in the hydrothermal environment had a profound effect on the surface morphology of the nanostructures. NaOH acted as both an etchant to convert TNT surfaces into low-dimensional structures and as a reducing agent to convert graphene oxide into reduced graphene oxide. Graphene oxide inhibited the etching rate to tune the surface morphologies into 1D, 2D, and 3D nanostructures. The electrochemical supercapacitance of all the nanostructures was characterized. Among the prepared samples, the nanostructured hybrid sample of reduced graphene oxide, titania nanoflakes, and TNT exhibited enhanced electrochemical performance with quite high specific capacitance. This superior electrochemical performance is attributed to the specific nanostructure, which provides short pathways for fast transport of salt ions and improved specific surface area for more adsorption sites for the formation of an electrical double layer, which leads to fast charge transfer.

The ultrasound-promoted one-pot multicomponent synthesis of substituted 3-pyrrolin-2-ones using citric acid as a green additive in a green solvent is reported. Citric acid catalyzed the reaction efficiently without the need for any other harmful organic reagents. Clean reaction profile, easy work-up procedure, excellent yields and short reaction times are some remarkable features of this method. The utilization of ultrasound irradiation makes this method potentially very useful, fast, clean and convenient.

Carbon-based conductive lines were directly patterned using an electrohydrodynamic (EHD) jet printing technique. We successfully dispersed multiwalled carbon nanotubes (MWCNTs) in a polar solvent through a size-sorting and blending process involving polystyrene sulfonate (PSS), and we fabricated a homogeneous MWCNT/PSS nano-composite ink for EHD printing. We demonstrated that EHD printing was affected by the type of solvent, which adjusted the surface tension of the MWCNT/PSS ink. Ethanol, with a lower surface tension compared to water, provided four different jetting modes, depending on the applied voltage and working distance. EHD-printed MWCNT/PSS conductive lines were used as source/drain (S/D) electrodes in organic field-effect transistors (OFETs). The resulting OFETs showed reliable performance with negligible hysteresis on chlorosilane-terminated polystyrene (PS-brush)-modified substrates.

Glutathione (GSH)-triggered drug releases of the anticancer drug mitoxantrone from a polyethylene glycol (PEG) (molecular weight: 5000) density-modulated drug delivery system up to 0.57 nm −2 of gold nanoparticles (AuNPs) were examined using bimodal spectroscopic imaging techniques of live-cell fluorescence imaging and surface-enhanced resonance Raman scattering (SERRS). Prolonged delivery amounts and sustained drug releases after introducing a high PEG density on AuNPs was supported by a cell viability test in HeLa cells. A subcutaneous in vivo test also indicated that the SERRS spectra could be observed only for the PEGylated AuNPs after external GSH treatment in consistent with the fluorescence measurements.

This study investigates nalidixic acid degradation via heterogeneous catalytic ozonation using clinoptilolite nanorods (CNs) as a novel nanocatalyst. Natural clinoptilolite microparticles (NCMs) were treated with a glow discharge plasma technique (GDP) to generate nanostructures. SEM, EDX, XRD, FT-IR, XPS, and BET were used to elucidate the morphology, chemical composition, and the microstructural properties of the NCMs and CNs. The SEM images of the untreated and plasma-treated clinoptilolite clarified that the morphology of the NCMs was converted to nanorods using the GDP technique. The catalytic performance of the NCMs and CNs in the heterogeneous catalytic ozonation of nalidixic acid was compared. The results demonstrate that in 60 min of the process, the removal efficiency is enhanced from 60.03% in the presence of NCMs to 91.08% when using the CNs. The effects of the main operational parameters and various reactive oxygen species (ROS) scavengers on the removal efficiency of nalidixic acid were thoroughly investigated. The main degradation by-products produced in the catalytic ozonation of nalidixic acid were identified by GC-MS. The ecotoxicity of nalidixic acid and the intermediate compounds formed in the process were evaluated using the aquatic species Lemna minor (L. minor).

Novel high-efficiency visible-light-sensitive Nd-doped CdTe nanoparticles were prepared with various doping concentrations of neodymium ion by a facile hydrothermal method. The reaction products were analyzed via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoelectron spectroscopy (XPS), and UV-Vis diffuse reflectance spectroscopy techniques. Red shift was seen in the absorption band edge peak in the UV-Vis absorbance spectrum with increasing Nd content. The XRD and XPS results confirmed that Nd ions successfully replaced Cd atoms and were incorporated into the crystal lattice of CdTe. SEM and TEM images indicated spherical structure and high crystallinity. Even at a very low Nd/CdTe molar ratio of 2 mol.%, Nd doping could greatly enhance the photocatalytic activity of CdTe. The photocatalytic activity of Nd-doped CdTe nanoparticles was evaluated by monitoring the decolorization of RRed 43 in aqueous solution under visible-light irradiation. The color removal efficiency of Nd0.08Cd0.92Te and pure CdTe were 83.14% and 14.32% after 100 min of treatment, respectively. Among different amounts of the doping agent, 8 mol.% Nd indicated the highest decolorization. The presence of radical scavengers such as Cl−, CO32−, SO42−, and buthanol was found to reduce the decolorization efficiency.

In this work, a Ca2+ selective PVC-membrane electrode, utilizing nano-sized Ca2+ imprinted polymers as the ionophore, was introduced. The imprinted polymer was prepared by precipitation polymerization in acetonitrile. Various types of commercially available functional monomers including methacrylic acid, acrylic acid and itaconic acid were tested for the synthesis of Ca2+-imprinted polymers. The networked polymers obtained were used as the ionophore of PVC membrane electrodes. The potentiometric responses of the electrodes, prepared using different imprinted polymers, showed that the type of functional monomers used had a crucial effect on the analytical characteristics of the related membrane electrode. The membrane electrode composed of itaconic acid based imprinted polymers showed better Nernstian slope and particularly better selectivity for Ca2+ determination. The effectiveness of itaconic acid for complex formation with Ca2+, in comparison to two other monomers (methacrylic acid and acrylic acid), was demonstrated by density functional theory-based calculations. The type of cross-linker agent had a definitive role in the performance of the related electrode. Divinyl benzene based imprinted polymers led to an electrode with no significant sensitivity for Ca2+; whereas, the utilization of ethylene glycol dimethacrylate led to a sensor with ideally Nernstian response. Other components of the membrane such as the plasticizer and ionic additive as well as the solution pH were evaluated and appropriate conditions were selected. The electrode showed a response time of 10 s with no memory effect. A dynamic linear range of 1 × 10−6–1 × 10−1 mol L−1, a Nernstian slope of 30.3 (±0.4) mV decade−1 and a detection limit of 7.5 × 10−7 mol L−1 were obtained for the electrode. The utility of the electrode was checked by its use as an indicator electrode in the determination of Ca2+ ions via complexometric titration by EDTA.

Two analytical approaches including chemiluminescence (CL) and corona discharge ionization ion mobility spectrometry (CD-IMS) were developed for sensitive determination of selegiline (SG). We found that the CL intensity of the KMnO4-Na2S2O3 CL system was significantly enhanced in the presence of L-cysteine capped CdS quantum dots (QDs). A possible CL mechanism for this CL reaction is proposed. In the presence of SG, the enhanced CL system was inhibited. Based on this inhibition, a simple and sensitive flow-injection CL method was proposed for the determination of SG. Under optimum experimental conditions, the decreased CL intensity was proportional to SG concentration in the range of 0.01 to 30.0 mg L(-1). The detection limit (3σ) was 0.004 mg L(-1). Also, SG was determined using CD-IMS, and under optimum conditions of CD-IMS, calibration curves were linear in the range of 0.15 to 42.0 mg L(-1), with a detection limit (3σ) of 0.03 mg L(-1). The precision of the two methods was calculated by analyzing samples containing 5.0 mg L(-1) of SG (n=11). The relative standard deviations (RSDs%) of the flow-injection CL and CD-IMS methods are 2.17% and 3.83%, respectively. The proposed CL system exhibits a higher sensitivity and precision than the CD-IMS method for the determination of SG.