Microscope-energy Dispersive X-ray Spectrometer Research Articles

Novel nontoxic electrochemical method for the detection of cefadroxil in pharmaceutical formulations and biological samples

The current study represented a novel nano-silver amalgam pastes microelectrode (nano-Ag-APME) as a suitable alternative for the assay of cefadroxil contents in pharmaceutical formulations and biological specimen. The proposed electrode prepared in a plastic tip of micropipette tied with the nano-silver amalgam pastes mainly comprise of silver nano-powder and pure mercury (1:9, w/w). The commercial silver nanopowder and nano-silver amalgam paste were characterized using scanning electron microscope–energy dispersive X-ray spectrometer and X-Ray Diffraction (XRD). These analyses depicted that nano-Ag amalgam paste formed Ag-Hg clusters consisting of a crystalline solid. The EDX analysis showed that all the chemical composition of the starting materials (silver nanopowder) consisted of the nano-Ag amalgam paste having Ag and Hg only. The optimization of different characteristics such as voltammetric modes, pH, type of supporting electrolytes, electrolyte volume, stirring rate, accumulation potential, and accumulation time for the determination of cefadroxil by SW-AdSV examined in detailed. The proposed method based on the square-wave stripping voltammetry for the measurement of cefadroxil at pH 4 in Britton–Robinson buffer, manifested a well-defined reduction peak at −0.160 V. The comparative study of SW-AdSV and spectrophotometric methods showed the linear response for CFL at a linear dynamic ranged from 0.033–0.304 and 10–70 µM, respectively. The analytical performance for the quantification of CFL by the SW-AdSV method was significantly good as compared to the spectrophotometric method (p < 0.01). Moreover, it has been indicated that the SW-AdSV is more sensitive and selective for precise routine analysis of CFL than the spectrophotometric method.

Micro-structural study of colored porcelains of Changsha kiln using imaging and spectroscopic techniques

Changsha kiln was an ancient factory from the Tang Dynasty (618–907 CE) to the Five Dynasties (907–960 CE), famous for its colored porcelain production. It was one of the pioneer sites to master the poly-color technique at high temperature. In this work, by using Energy Dispersive X-Ray Fluorescence (EDXRF), Raman spectroscopy and Scanning Electron Microscopy Energy Dispersive X-ray Spectrometer (SEM-EDS), the composition and structure of two of its emblematic colored glazes were studied. The results confirmed that the chromogenic elements of brown and green colored glazes are well iron and copper respectively. They also revealed a significant presence of hematite (α-Fe2O3) phase with dendritic shape close to the glaze surface and oddly a substantial amount of ε-Fe2O3 phase at the body/glaze interface. It is the second type of ancient Chinese glaze in which the very rare and metastable iron(III) oxide polymorph was found. No Cu-based particle was identified in green glaze. The green color is certainly due to Cu2+ dispersed in the glassy matrix. Our study confirmed that Cassiterite (SnO2) was used as opacifier compound to obtain opaque green color.

Synthesis and Magneto–Thermal properties of NiPd nanoparticles

In this study, two NiPd magnetic alloys, i.e., Ni30Pd70 and Ni50Pd50, were synthesized for use in magnetic hyperthermia. The alloys were synthesized using the polyol method and identified using a powder X-ray diffractometer (XRD), transmission electron microscope (TEM), scanning electron microscope–energy dispersive X-ray spectrometer, and vibrating sample magnetometer. The magneto–thermal properties were determined using a fiber optic thermometer and induction heating system.The average crystal sizes of the Ni30Pd70 and Ni50Pd50 alloys were determined to be 3.48 ± 0.04 nm and 2.47 ± 0.11 nm, respectively, based on the XRD patterns. The magnetization measurements indicated that Ni30Pd70 sample exhibited paramagnetic property while the Ni50Pd50 alloy shows superparamagnetic and ferromagnetic behaviors at room temperature. The magnetization versus temperature measurements showed that the blocking temperature of the Ni30Pd70 alloy was less than 10 K and the blocking temperature of the Ni50Pd50 alloy was around 155 K. The specific absorption rate values were calculated to range between 0.2 and 7.6 W g−1 based on magneto-thermal experiments under the AC magnetic field ranging from 8.7 to 23.7 kA/m.

Evaluation of Antibacterial Effect by Using a Fibrous Grafted Material Loaded Ag Ligand

To obtain the safety of drinking water, an antibacterial material was prepared by loading silver (Ag) onto fibrous iminodiacetate (IDA) adsorbent, which was synthesized by radiation-induced graft polymerization of glycidyl methacrylate and subsequent chemical modification of the produced epoxy group to an IDA group (IDA-Ag). A total amount of loaded Ag on the IDA-Ag fabric was 0.4 mmol-Ag/g-fabric. From an observation of the IDA-Ag fabric cross section by a scanning electron microscope energy dispersive X-ray spectrometer, Ag was distributed to IDA layer uniformly. As a result of evaluating antibacterial effects by the column mode water flow test with stream water, the effective Ag concentration was monitored 0.05 ppm at irrespective flow rate which was functioned to the antibacterial performance. The antibacterial effects for general bacteria were indicated until BV (BV: steam water volume/IDA-Ag fabric volume) 6000, and for colitis germ legions were completely disinfected until BV 6000.

Investigation of Compositional Change of Inclusions in Martensitic Stainless Steel during Heat Treatment by Newly Developed Analysis Method

The most important subject in the steelmaking process is the control of non-metallic inclusions. Non-metallic inclusions with a high melting point do not deform during a hot working process because they are relatively hard. Hence, the inclusion composition should be controlled in order to achieve a low melting point to prevent product defects. Therefore, an MnO–SiO2-based inclusion is considered to be one of the preferred systems. Moreover, the heat treatment of austenitic stainless steel has been reported to influence the composition of MnO–SiO2-type inclusions; these inclusions change into MnO–Cr2O3-type, MnO–Nb2O5-type, and MnO–V2O3-type inclusions. In this study, we investigated the influence of heat treatment on the composition of the inclusions in the martensitic stainless steel. In general, a scanning electron microscope–energy dispersive x-ray spectrometer (SEM–EDS) is used for the quantitative analysis of inclusions; however, SEM–EDS cannot simultaneously analyze a large number of inclusions. Therefore, a new technique using the SEM–EDS along with the image analysis software “Particle Analysis” was used for the chemical analysis and the size measurement of a large number of inclusions (hereafter abbreviated as the PA method). The heat-treatment-induced compositional change of the inclusions in martensitic stainless steel was evaluated by using both the analysis methods.

Diffusion of chromium in chrysoberyl

Cr 3+ diffusion in chrysoberyl (BeAl 2O 4) irradiated by H + ions and electrons has been studied and compared with diffusion in non-irradiated samples. Chrysoberyl crystals were irradiated with 6 MeV H + ions to fluencies of 1×10 16 cm –2 for 25 min and with 10 MeV electrons to fluencies of 2×10 17 cm –2 for 1 h. Three different types of samples, which were doped with Cr 3+, were annealed in horizontal alumina tube furnaces by 50 K intervals in the temperature range from 1773 to 1923 K for 200 h. Scanning electron microscope–energy dispersive X-ray spectrometer (SEM–EDX) was used to measure the diffusion. Arrhenius equations for the diffusion coefficient for Cr 3+ in the temperature range 1773–1923 K were developed: Electron beam irradiated chrysoberyls, D cr=2.1×10 −5×exp (−482.3±18.2 kJ mol −1/ RT)m 2 s −1 Proton beam irradiated chrysoberyls, D cr=2.3×10 −3×exp (−545.4±25.0 kJ mol −1/ RT)m 2 s −1 Natural non-irradiated chrysoberyls D cr=2.2×10 −3×exp (−547.9±36.8 kJ mol −1/ RT)m 2 s −1 The results indicate that the chromium diffuses deepest into the electron beam irradiated chrysoberyls.

Identification of hydrated cement constituents using a scanning electron microscope energy dispersive X-ray spectrometer combination

Preliminary studies of the chemical composition of individual particles and local areas in hydrated cement pastes were carried out using a scanning electron microscope-energy dispersive x-ray spectrometer combination. Calibration curves prepared from a series of homogeneous cement and hydrated cement compounds were used, the analysis being carried out in terms of ratios of calcium oxide to silicon, sulfur, and aluminum oxides. Sulfur was distributed throughout the calcium silicate hydrate gel, except for regions thought to represent “inner” hydration product. Apparent mole ratios of calcium oxide to silica ranged generally between 2 and 3, considerably higher than had been expected. Various morphological features were interpreted in the light of their chemical compositions.