scholarly journals Physicochemical and Adsorption Characteristics of Divinylbenzene-co-Triethoxyvinylsilane Microspheres as Materials for the Removal of Organic Compounds

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2396
Author(s):  
Alicja Bosacka ◽  
Małgorzata Zienkiewicz-Strzalka ◽  
Małgorzata Wasilewska ◽  
Anna Derylo-Marczewska ◽  
Beata Podkościelna
Keyword(s):  
Organic Compounds ◽  
Spherical Shape ◽  
Kinetic Studies ◽  
Inorganic Materials ◽  
Molar Ratio ◽  
Water And Wastewater Treatment ◽  
Molar Ratios ◽  
X Ray Scattering ◽  
Complementary Techniques ◽  
Saxs Analysis

In this work, organic-inorganic materials with spherical shape consisting of divinylbenzene (DVB) and triethoxyvinylsilane (TEVS) were synthesized and investigated by different complementary techniques. The obtained microspheres may be applied as sorbent systems for the purification of organic compounds from water. The hybrid microspheres combine the properties of the constituents depending on the morphologies and interfacial bonding. In this work, the influence of the molar ratio composition of crosslinked monomer (DVB) and silane coupling agent (TEVS) (DVB:TEVS molar ratios: 1:2, 1:1 and 2:1) on the morphology and quality of organic-inorganic materials have been examined. The materials were analysed using small angle X-ray scattering (SAXS) analysis, low-temperature nitrogen sorption, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) to provide information on their structural and surface properties. Moreover, thermal analysis was performed to characterize the thermal stability of the studied materials and the adsorbent-adsorbate interactions, while adsorption kinetic studies proved the utility of the synthesized adsorbents for water and wastewater treatment.

scholarly journals A novel potential nanophototherapeutic based on the assembly of an amphiphilic cationic β-cyclodextrin and an anionic porphyrin

2017 ◽  
Vol 21 (04-06) ◽  
pp. 398-405 ◽  
Author(s):  
Antonino Mazzaglia ◽  
Norberto Micali ◽  
Valentina Villari ◽  
Roberto Zagami ◽  
Rosa Maria Pennisi ◽  
...  
Keyword(s):  
Molar Ratio ◽  
Organic Film ◽  
Time Resolved Fluorescence ◽  
Distribution Profile ◽  
Time Resolved ◽  
Molar Ratios ◽  
Complementary Techniques ◽  
Biological Environment ◽  
Aging Phenomena ◽  
Tumoral Cells

The development of cyclodextrin nanoassemblies as useful carriers for photosensitizer drugs (PS) delivery in biological environment is a topic of increasing interest. In this paper, we present a spectroscopic investigation on a nanosystem based on an amphiphilic cationic β-cyclodextrin derivative (CD-N) and an anionic porphyrin (TPPS). Nanoassemblies were prepared by hydration of an organic film containing the two species. The system was characterized by complementary techniques such as UV-vis, stationary and time-resolved fluorescence, and Dynamic Light Scattering (DLS) at different TPPS/CD-N molar ratios. Time-resolved fluorescence data showed that, at all the investigated molar ratios, TPPS is present both as self-aggregated species and monomers forming supramolecular adducts with CD-N. Moreover, DLS measurements evidenced families of aggregates having hydrodynamic radii ranging between 50 and 350 nm and the size distribution profile depending on the TPPS/CD-N molar ratio. At the highest CD-N concentration, the hydrodynamic radii of the aggregates were nearly the same as those of neat CD-N in the absence of TPPS (50 nm). No aging phenomena were registered, pointing out the high stability of these nanoassemblies in aqueous solution for at least a month. Preliminary studies on the internalization in tumoral cells and subsequent irradiation for PDT application were carried out. The results support the feasibility of these nanoaggregates to promote PS internalization in HeLa cells, inducing cell death upon visible light irradiation.

scholarly journals Kinetics of Arsenic Removal in Waste Acid by the Combination of CuSO4 and Zero-Valent Iron

Processes ◽  
2019 ◽  
Vol 7 (7) ◽  
pp. 401 ◽  
Author(s):  
Yunhao Xi ◽  
Yongguang Luo ◽  
Jingtian Zou ◽  
Jing Li ◽  
Tianqi Liao ◽  
...  
Keyword(s):  
Arsenic Removal ◽  
Reaction Order ◽  
Kinetic Studies ◽  
Zero Valent Iron ◽  
Molar Ratio ◽  
Molar Ratios ◽  
Before And After ◽  
Shrinking Core ◽  
Kinetics Of ◽  
Waste Acid

In this study, we investigated the kinetics of arsenic removal from waste acid by the combination of zero-valent iron (ZVI) and CuSO4. ZVI samples were characterized by X-ray diffraction and scanning electron microscopy before and after arsenic removal; the results showed that after the arsenic removal reaction, As2O3 and magnetite phases were detected on the surface of these samples. Kinetic studies were carried out under different reaction temperatures, with different CuSO4 concentrations, and with different iron to arsenic molar ratios (Fe/As). The kinetic data of the arsenic removal were fitted to different kinetic models. The fitting results showed that the arsenic removal process could be described by the shrinking core model, controlled by residual layer diffusion. The apparent activation energy of the reaction was 9.0628 kJ/mol, the reaction order with the CuSO4 concentrations was −0.12681, and the reaction order with the molar ratio of iron to arsenic (Fe/As) was 3.152.

scholarly journals Photocatalytic Reduction of CO2 to Methanol Using a Copper-Zirconia Imidazolate Framework

Catalysts ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 346
Author(s):  
Sonam Goyal ◽  
Maizatul Shima Shaharun ◽  
Ganaga Suriya Jayabal ◽  
Chong Fai Kait ◽  
Bawadi Abdullah ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Catalyst Support ◽  
Oxidation Potential ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Optimum Parameters ◽  
Reduction Of Co2 ◽  
Enhanced Yield

A set of novel photocatalysts, i.e., copper-zirconia imidazolate (CuZrIm) frameworks, were synthesized using different zirconia molar ratios (i.e., 0.5, 1, and 1.5 mmol). The photoreduction process of CO2 to methanol in a continuous-flow stirred photoreactor at pressure and temperature of 1 atm and 25 °C, respectively, was studied. The physicochemical properties of the synthesized catalysts were studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy. The highest methanol activity of 818.59 µmol/L.g was recorded when the CuZrIm1 catalyst with Cu/Zr/Im/NH4OH molar ratio of 2:1:4:2 (mmol/mmol/mmol/M) was employed. The enhanced yield is attributed to the presence of Cu2+ oxidation state and the uniformly dispersed active metals. The response surface methodology (RSM) was used to optimize the reaction parameters. The predicted results agreed well with the experimental ones with the correlation coefficient (R2) of 0.99. The optimization results showed that the highest methanol activity of 1054 µmol/L.g was recorded when the optimum parameters were employed, i.e., stirring rate (540 rpm), intensity of light (275 W/m2) and photocatalyst loading (1.3 g/L). The redox potential value for the CuZrIm1 shows that the reduction potential is −1.70 V and the oxidation potential is +1.28 V for the photoreduction of CO2 to methanol. The current work has established the potential utilization of the imidazolate framework as catalyst support for the photoreduction of CO2 to methanol.

scholarly journals Pilot study on the effects of preservatives on corneal collagen parameters measured by small angle X-ray scattering analysis

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Susyn Joan Kelly ◽  
Lizette duPlessis ◽  
John Soley ◽  
Frazer Noble ◽  
Hannah Carolyn Wells ◽  
...  
Keyword(s):  
Small Angle ◽  
Collagen Fibril ◽  
Diameter Distribution ◽  
X Ray ◽  
X Ray Scattering ◽  
Saxs Analysis ◽  
Triton X ◽  
Fibril Diameter ◽  
Corneal Collagen ◽  
Ray Scattering

Abstract Objective Small angle X-ray scattering (SAXS) analysis is a sensitive way of determining the ultrastructure of collagen in tissues. Little is known about how parameters measured by SAXS are affected by preservatives commonly used to prevent autolysis. We determined the effects of formalin, glutaraldehyde, Triton X and saline on measurements of fibril diameter, fibril diameter distribution, and D-spacing of corneal collagen using SAXS analysis. Results Compared to sections of sheep and cats’ corneas stored frozen as controls, those preserved in 5% glutaraldehyde and 10% formalin had significantly larger mean collagen fibril diameters, increased fibril diameter distribution and decreased D-spacing. Sections of corneas preserved in Triton X had significantly increased collagen fibril diameters and decreased fibril diameter distribution. Those preserved in 0.9% saline had significantly increased mean collagen fibril diameters and decreased diameter distributions. Subjectively, the corneas preserved in 5% glutaraldehyde and 10% formalin maintained their transparency but those in Triton X and 0.9% saline became opaque. Subjective morphological assessment of transmission electron microscope images of corneas supported the SAXS data. Workers using SAXS analysis to characterize collagen should be alerted to changes that can be introduced by common preservatives in which their samples may have been stored.

scholarly journals Lipozyme 435-Mediated Synthesis of Xylose Oleate in Methyl Ethyl Ketone

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3317
Author(s):  
Maria Carolina Pereira Gonçalves ◽  
Jéssica Cristina Amaral ◽  
Roberto Fernandez-Lafuente ◽  
Ruy de Sousa Junior ◽  
Paulo Waldir Tardioli
Keyword(s):  
Oleic Acid ◽  
Methyl Ethyl Ketone ◽  
Molar Ratio ◽  
Methyl Ethyl ◽  
Sugar Ester ◽  
Molar Ratios ◽  
Emulsion Capacity ◽  
Ping Pong ◽  
Commercial Sugar ◽  
Repeated Use

In this paper, we have performed the Lipozyme 435-catalyzed synthesis of xylose oleate in methyl ethyl ketone (MEK) from xylose and oleic acid. The effects of substrates’ molar ratios, reaction temperature, reaction time on esterification rates, and Lipozyme 435 reuse were studied. Results showed that an excess of oleic acid (xylose: oleic acid molar ratio of 1:5) significantly favored the reaction, yielding 98% of xylose conversion and 31% oleic acid conversion after 24 h-reaction (mainly to xylose mono- and dioleate, as confirmed by mass spectrometry). The highest Lipozyme 435 activities occurred between 55 and 70 °C. The predicted Ping Pong Bi Bi kinetic model fitted very well to the experimental data and there was no evidence of inhibitions in the range assessed. The reaction product was purified and presented an emulsion capacity close to that of a commercial sugar ester detergent. Finally, the repeated use of Lipozyme 435 showed a reduction in the reaction yields (by 48 and 19% in the xylose and oleic acid conversions, respectively), after ten 12 h-cycles.

scholarly journals Biosynthesis of CeO2 Nanoparticles Using Egg White and Their Antibacterial and Antibiofilm Properties on Clinical Isolates

Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 584
Author(s):  
Shalendra Kumar ◽  
Faheem Ahmed ◽  
Nagih M. Shaalan ◽  
Osama Saber
Keyword(s):  
Bacterial Infections ◽  
Antibacterial Properties ◽  
Spherical Shape ◽  
Inhibition Zone ◽  
Egg White ◽  
Ceo2 Nanoparticles ◽  
Inorganic Materials ◽  
Ambient Conditions ◽  
Uniform Size ◽  
Tem Analysis

Bio-inspired synthesis is a novel and attractive environmentally friendly route to generating inorganic materials. In this work, the preparation of CeO2 NPs using egg white and investigation of their antibacterial properties both in liquid and solid growth medium against Escherichia coli and Staphylococcus aureus bacteria were reported. The CeO2 nanoparticles were characterized using X-ray diffraction (XRD), Field emission transmission electron microscope (FETEM), UV-Vis, Raman, and antibacterial measurements. The results from XRD and TEM analysis showed that the prepared nanoparticles were a single phase in the nano regime (5–7 nm) with spherical shape and uniform size distribution. Optical properties reflected the characteristics peaks of CeO2 in the UV-Vis range with a bandgap ~2.80 eV. The antibacterial activity of the synthesized NPs was achieved under ambient conditions with different bacteria and the results showed that the properties were different for both the bacteria. The highest activity with an inhibition zone of about 22 mm against S. aureus was obtained as compared with the 19 mm zone of inhibition obtained with E.coli. This finding will be of major significance that indicates a possibility to develop CeO2 NPs as antibacterial agents against extensive microorganisms to control and prevent the spread and persistence of bacterial infections.

scholarly journals Exploring the in meso crystallization mechanism by characterizing the lipid mesophase microenvironment during the growth of single transmembrane α-helical peptide crystals

2016 ◽  
Vol 374 (2072) ◽  
pp. 20150125 ◽  
Author(s):  
Leonie van 't Hag ◽  
Konstantin Knoblich ◽  
Shane A. Seabrook ◽  
Nigel M. Kirby ◽  
Stephen T. Mudie ◽  
...  
Keyword(s):  
Crystal Growth ◽  
Self Assembly ◽  
Lamellar Phase ◽  
Cubic Phase ◽  
Supporting Evidence ◽  
X Ray ◽  
X Ray Scattering ◽  
Standard Procedures ◽  
Helical Peptide ◽  
Saxs Analysis

The proposed mechanism for in meso crystallization of transmembrane proteins suggests that a protein or peptide is initially uniformly dispersed in the lipid self-assembly cubic phase but that crystals grow from a local lamellar phase, which acts as a conduit between the crystal and the bulk cubic phase. However, there is very limited experimental evidence for this theory. We have developed protocols to investigate the lipid mesophase microenvironment during crystal growth using standard procedures readily available in crystallography laboratories. This technique was used to characterize the microenvironment during crystal growth of the DAP12-TM peptide using synchrotron small angle X-ray scattering (SAXS) with a micro-sized X-ray beam. Crystal growth was found to occur from the gyroid cubic mesophase. For one in four crystals, a highly oriented local lamellar phase was observed, providing supporting evidence for the proposed mechanism for in meso crystallization. A new observation of this study was that we can differentiate diffraction peaks from crystals grown in meso , from peaks originating from the surrounding lipid matrix, potentially opening up the possibility of high-throughput SAXS analysis of in meso grown crystals. This article is part of the themed issue ‘Soft interfacial materials: from fundamentals to formulation’.

Preparation of CuO Nanopowder in Aqueous Solution by Applying Ultrasonic and its CO Gas Sensitivity

2007 ◽  
Vol 544-545 ◽  
pp. 901-904 ◽  
Author(s):  
Ji Bum Yang ◽  
Tae Gyung Ko ◽  
Sang Jin Jung ◽  
Jae Hee Oh
Keyword(s):  
Aqueous Solution ◽  
Gas Sensing ◽  
Spherical Shape ◽  
Particle Morphology ◽  
High Yield ◽  
Ambient Conditions ◽  
Gas Sensitivity ◽  
Molar Ratios ◽  
Naoh Solution ◽  
Co Gas

We report on a process in which CuO nanopowder was produced in a high yield by adopting ultrasonic in aqueous solution. In our experiment, CuCl2 solution was reacted with NaOH solution and NaNO2, at ambient conditions applying ultrasonic for 5 min. Precipitation was performed by varying the molar ratios of NaOH/CuCl2 and NaNO2/CuCl2. CuO nanoparticles of ~ 5 nm and spherical shape were obtained at the NaOH/CuCl2 of 2.0 and the NaNO2/CuCl2 of 0.097. Without ultrasonication, an amorphous phase was formed at these conditions. This indicates that sonochemical reaction facilitates direct formation of the nanosized CuO particles. In addition, the particle morphology varied from sphere through ellipsoid to needle forms depending on pH. In thick films prepared with the CuO powder for gas sensing, the maximum CO gas sensitivity reached 93 % at the temperature of 250 °C and depended linearly on CO concentration in log scale over the range of 10 ~ 104 ppm.

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