Microwave hydrothermal synthesis,characterisation, and catalytic performance of Zn1−x Mn x O in cellulose conversion

Wurtzite-type Zn_1?x Mn _x O (x = 0, 0.03, 0.05, 0.07) nanostructures were successfully synthesised using a simple microwave-assisted hydrothermal route and their catalytic properties were investigated in the cellulose conversion. The morphology of the nanocatalysts is dopant-dependent. Pure ZnO presented multi-plate morphology with a flower-like shape of nanometric sizes, while the Zn_0.97Mn_0.03O sample is formed by nanoplates with the presence of spherical nanoparticles; the Zn_0.95Mn_0.05O and Zn_0.93Mn_0.07O samples are mainly formed by nanorods with the presence of a small quantity of spherical nanoparticles. The catalyst without Mn did not show any catalytic activity in the cellulose conversion. The Mn doping promoted an increase in the density of weak acid sites which, according to the catalytic results, favoured promotion of the reaction.     

Effect of the electrodeposition potential on the photoelectroactivity of the SnS/Sb2S3 thin films

Journal of Solid State Electrochemistry - The present work outlines a simple and novel approach to obtain nanostructured and heterostructured SnS/Sb2S3 thin films. This material showed enhanced...     

Correction to: Interlaboratory Reproducibility of Contour Method Data Analysis and Residual Stress Calculation

Experimental Mechanics - The original version of this article has been corrected to include authors middle initials in the author list. The details given in this correction are correct.     

Speckle interferometry methods for displacement and strain measurements using photorefractive crystal

Photorefractive crystals offer several attractive features such as high resolution and in situ processing. As the images are erasable, these crystals are suitable for read–write applications and hence find potential use in speckle photography, image processing and holography. The barium titanate (BaTiO₃) crystal as recording medium has been extensively used as a novelty filter for real-time in-plane displacement measurements employing two-beam coupling configuration. This paper presents new optical configurations in speckle shear photography to measure in-plan displacement and the strain in real time using BaTiO₃ crystal as recording medium. Speckle photography studies are made using a simple two-beam coupling configuration. In speckle shear photography, a diffused object illuminated with two parallel narrow laser beams is imaged inside the crystal, and a pump beam is added at this plane. The speckle patterns due to each beam and the pump beam produce index gratings. When the object is deformed, the speckle patterns shift consequently. We now have four speckle fields: two generated from the interaction of pump beam with the index gratings and two pertaining to deformed states directly transmitted through the crystal. Thus, the fields from respective points on the object interfere after passage through the crystal and produce the Young's fringe patterns. Due to strain, the fringes in each pattern are of different width and orientation, resulting in the generation of a Moiré pattern. The strain is obtained from the width and orientation of the fringes in the Moiré pattern. The experiments are conducted on a specimen with a notch, which is subjected to tensile loading. The in-plane displacement is measured separately in another experiment. The above studies are carried out at Nd–Yag laser.     

Purity assessment using the mass balance approach for inorganic in-house certified reference material production at Inmetro

Accreditation and Quality Assurance - The production of Certified Reference Materials (CRMs) is one of the essential activities of the National Institute of Metrology, Quality and Technology...     

Mössbauer study of spin-glass Fe x Zn1−x F2 system

⁵⁷Fe Mössbauer effect measurements in the diluted Ising antiferromagnet Fe _x Zn_1?x F₂ withx=0.25 andx=0.57 at temperatures between 4.2 and 55 K, are reported. DC suceptibility measurements show a spin-glass (SG) phase at low temperatures forx≤0.31. Our Mössbauer spectra show a phase transition to a SG state with antiferromagnetic order (AFSG) forx=0.25 and only antiferromagnetic order forx=0.57.     

Novel fabrication route for carbon-free and dense CuInSe2 (CIS) thin films via a non-vacuum process for solar cell application

Carbon-free CuInSe₂ (CIS) thin film with a dense microstructure has been prepared using a novel non-vacuum based fabrication route. Cu_xS_y and In₂Se₃ binary nanoparticles, approximately 10 nm in size, were synthesized by a low temperature colloidal process. The precursor film was deposited using the coating ink formulated with the binary nanoparticles and pyridine, and then annealed in the rapid thermal annealing (RTA) chamber at 540 °C for 15 min under selenium (Se) atmosphere. Scanning electron micrographs, X-ray diffraction patterns and Raman spectra showed a phase pure carbon-free and dense CIS thin film was prepared in this method. A solar cell device fabricated using this CIS thin film showed the following photovoltaic characteristics: V_OC = 350 mV, J_SC = 24.72 mA cm⁻², FF = 38.73% and η = 3.36% under standard AM 1.5 condition.     

Scanning electron microscopy of Ancylostoma spp. dog infective larvae captured and destroyed by the nematophagous fungus Duddingtonia flagrans

The interaction between the nematode-trapping fungus Duddingtonia flagrans (isolate CG768) against Ancylostoma spp. dog infective larvae (L₃) was evaluated by means of scanning electron microscopy. Adhesive network trap formation was observed 6 h after the beginning of the interaction, and the capture of Ancylostoma spp. L₃ was observed 8 h after the inoculation these larvae on the cellulose membranes colonized by the fungus. Scanning electron micrographs were taken at 0, 12, 24, 36 and 48 h, where 0 is the time when Ancylostoma spp. L₃ was first captured by the fungus. Details of the capture structure formed by the fungus were described. Nematophagous Fungus Helper Bacteria (NHB) were found at interactions points between the D. flagrans and Ancylostoma spp. L₃. The cuticle penetration by the differentiated fungal hyphae with the exit of nematode internal contents was observed 36 h after the capture. Ancylostoma spp. L₃ were completely destroyed after 48 h of interaction with the fungus. The scanning electron microscopy technique was efficient on the study of this interaction, showing that the nematode-trapping fungus D. flagrans (isolate CG768) is a potential exterminator of Ancylostoma spp. L₃.