Assimilation of Zinc Metal Ion With Hydroxyapatite for Impedance Studies

The aim of the present work is to examine the doping outcome of Zn metal ions on hydroxyapatite for different concentrations (0.2, 0.4, 0.6, and 0.8). The samples for the pure and Zn doped HAp are synthesized by wet chemical precipitation method. The properties and the particle size are identified by using XRD. The functional bands of PO, CO and OH are analyzed through FTIR and the surface morphology and particle shapes are studied through SEM. The elemental analysis such as zinc, calcium and phosphates are analyzed by EDAX. All the designed elements are studied and confirm the (Ca+Zn)/PO ratio is nearly 1.67 and no other elements were identified in this study. The morphological particles of needle shape and the nanoscale particle size and shapes are studied by using TEM. The electrical conductivity of the synthesized ZnHAp ceramic is mainly related to width of the channel and the polarizability. The frequency dependence of the electric and dielectric properties was studied by using impedance spectroscopy.

Assimilation of Zinc Metal Ion With Hydroxyapatite for Formation and Dielectric Studies

The aim of the present work is to investigate the doping effect of Zn metal ions on hydroxyapatite for different concentrations (0.2, 0.4, 0.6, and 0.8). The samples for the pure and Zn doped HAp are synthesized by wet chemical precipitation method. The properties and the particle size are identified by using XRD. The functional bands of PO, CO and OH are analyzed through FTIR and the surface morphology and particle shapes are studied through SEM. The elemental analysis such as zinc, calcium and phosphates are analyzed by EDAX. All the designed elements are studied and confirm the (Ca+Zn)/PO ratio is nearly 1.67 and no other elements were identified in this study. The morphological particles of needle shape and the nanoscale particle size and shapes are studied by using TEM. The electrical conductivity of the synthesized ZnHAp ceramic is mainly related to width of the channel and the polarizability. The dielectric loss and nyquist plots were studied by using impedance spectroscopy.

Valorization of Rice Straw via Hydrotropic Lignin Extraction and Its Characterization

Rice straw hydrotropic lignin was extracted from p-Toluene sulfonic acid (p-TsOH) fractionation with a different combined delignification factor (CDF). Hydrotropic lignin characterization was systematically investigated, and alkaline lignin was also studied for the contrast. Results showed that the hydrotropic rice straw lignin particle was in nanometer scopes. Compared with alkaline lignin, the hydrotropic lignin had greater molecular weight. NMR analysis showed that β-aryl ether linkage was well preserved at low severities, and the unsaturation in the side chain of hydrotropic lignin was high. H units and G units were preferentially degraded and subsequently condensed at high severity. High severity also resulted in the cleavage of part β-aryl ether linkage. 31P-NMR showed the decrease in aliphatic hydroxyl groups and the increasing carboxyl group content at high severity. The maximum weight loss temperature of the hydrotropic lignin was in the range of 330–350 °C, higher than the alkaline lignin, and the glass conversion temperature (Tg) of the hydrotropic lignin was in the range of 107–125 °C, lower than that of the alkaline lignin. The hydrotropic lignin has high β-aryl ether linkage content, high activity, nanoscale particle size, and low Tg, which is beneficial for its further valorization.

The Effect of the Chorion on Size-Dependent Acute Toxicity and Underlying Mechanisms of Amine-Modified Silver Nanoparticles in Zebrafish Embryos

As the worldwide application of nanomaterials in commercial products increases every year, various nanoparticles from industry might present possible risks to aquatic systems and human health. Presently, there are many unknowns about the toxic effects of nanomaterials, especially because the unique physicochemical properties of nanomaterials affect functional and toxic reactions. In our research, we sought to identify the targets and mechanisms for the deleterious effects of two different sizes (~10 and ~50 nm) of amine-modified silver nanoparticles (AgNPs) in a zebrafish embryo model. Fluorescently labeled AgNPs were taken up into embryos via the chorion. The larger-sized AgNPs (LAS) were distributed throughout developing zebrafish tissues to a greater extent than small-sized AgNPs (SAS), which led to an enlarged chorion pore size. Time-course survivorship revealed dose- and particle size-responsive effects, and consequently triggered abnormal phenotypes. LAS exposure led to lysosomal activity changes and higher number of apoptotic cells distributed among the developmental organs of the zebrafish embryo. Overall, AgNPs of ~50 nm in diameter exhibited different behavior from the ~10-nm-diameter AgNPs. The specific toxic effects caused by these differences in nanoscale particle size may result from the different mechanisms, which remain to be further investigated in a follow-up study.

THE EFFECT OF TiO2 AS ADDITIVES ON PROPERTIES OF COMPOSITE MgO FOR BONE REPAIR

Magnesium oxide (MgO) is regarded as a biocompatible material. A composite material fromMgO oxide prepared by mixing MgO powder with TiO2 (rutile phase) (2, 5, 10)Wt.% usingpowder metallurgy technique. It is used to be bioceramic material. The compressed sampleswere dried and sintered at (1200) ᵒC. porosity measurement showed that the porositydecreasing with increasing TiO2% . X-ray showed the presence of Mg2TiO4 in the compositestructure of MgO with (5, 10)%TiO2 samples.The mechanical study showed an increasing in compressive strength, hardness, wearresistance and biodegradation resistance with increasing TiO2% content in the limit of usedpercentage. The prepared composite material didn’t present antibacterial activity whileprevious researches showed opposite result because of using nanoscale particle size of MgO.

Facile synthesis, morphology and photoluminescence of a novel red fluoride nanophosphor K2NaAlF6:Mn4+

A novel red-emitting fluoride phosphor, K2NaAlF6:Mn4+, with nanoscale particle size was synthesizedviaa cation exchange route.

SnO2Nanoparticle-Based Passive Capacitive Sensor for Ethylene Detection

A passive capacitor-based ethylene sensor using SnO2nanoparticles is presented for the detection of ethylene gas. The nanoscale particle size (10 nm to 15 nm) and film thickness (1300 nm) of the sensing dielectric layer in the capacitor model aid in sensing ethylene at room temperature and eliminate the need for microhotplates used in existing bulk SnO2-resistive sensors. The SnO2-sensing layer is deposited using room temperature dip coating process on flexible polyimide substrates with copper as the top and bottom plates of the capacitor. The capacitive sensor fabricated with SnO2nanoparticles as the dielectric showed a total decrease in capacitance of 5 pF when ethylene gas concentration was increased from 0 to 100 ppm. A 7 pF decrease in capacitance was achieved by introducing a 10 nm layer of platinum (Pt) and palladium (Pd) alloy deposited on the SnO2layer. This also improved the response time by 40%, recovery time by 28%, and selectivity of the sensor to ethylene mixed in a CO2gas environment by 66%.