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ABSTRACTDevelopment of various alternative routes for the direct reduction of iron-ore (DRI) and production of sponge irons becomes a necessity today to reduce carbon dioxide (CO2) gas emissions in industrial iron & steel (I&S) making processes. Therefore, the main objective of this work is focused to reduce the carbon footprint in DRI production by eliminating fossil fuel consumption. The reduced iron could be used to melt in the electric arc furnace (EAF) to produce liquid steel by minimising direct scrap addition. Indeed, this paper shows an advanced physical model of a hydrogen fuel shaft furnace for the direct reduced iron-making process by fundamental development of technology with essential modifications in its working principle. This processing technology is hypothetically designed with knowledge of theoretical literature inputs and wisdom of iron and steel-making experience. In this model of a shaft furnace, a scientific approach is designed based on the dissociation of molecular-hydrogen gas (H2+) obtained by water electrolysis and ionisation of the hydrogen gas (2H+) and is incorporated for a high degree of gas adsorption and metallisation during chemical reduction of iron ore (Fe2O3) pellets. The steps involved in the working principle of the new design shaft furnace are simulated and modelled suitably for the existing Midrex furnace operation, which is generally used for DRI production. This approach could be tried using 100% dissociated hydrogen ionic gas (2H+, H+) for future direct reduced iron making by water electrolysis and hydrogen ionisation. Moreover, the reformed reducing gases (CH4–H2–CO) used in the Midrex process can be replaced by the ionised hydrogen gases as an advancement.

Over the past decade, oxy-fluoride glasses are the subject of investigation by many researchers. Calcium fluoride incorporated alumina-bismuth borate glasses reinforced with minute quantity of copper ions have been synthesized by melt-quenching process and the amorphous nature is approved by X-ray diffraction (XRD) spectra. The samples are further analyzed, to know the effect of Al2O3on CaF2-Bi2O3-B2O3–CuO glasses, with the help of density, molar volume, optical, electron paramagnetic resonance (EPR), and Raman and Fourier transform infrared (FTIR) spectra. A decreasing trend was observed in density values with increasing Al2O3even though the relative density of Al2O3is higher than the CaF2. This decrease in density is attributed to the larger bond length of Al-O in AlO4units as compared to B-O bond length in BO3and BO4units. The bandgap values estimated from optical absorption spectra were found to increase with Al2O3content, indicating the decrement in the number of non-bridging oxygens. Spin-Hamiltonian parameters g‖>g⊥>ge(ge= 2.0023) and A‖>A⊥are of the opinion that the Cu2+ions were taken the positions of octahedral sites with tetragonal distortion and ground state being dx2-y2orbital. FTIR and Raman spectra suggested that these glasses are composed of BiO6, BO3, BO4, and alumina polyhedral.

To evaluate the effect of In2O3on (30-x) BaO-69B2O3-xIn2O3-1CuO (x= 0.5, 1.0, 1.5, 2.0 and 2.5 mol%) glasses are described for their spectroscopic properties as well as physical and optical qualities. Bragg’s peak-free X-ray diffractograms confirmed the samples’ non-crystalline character. The increase of In2O3mole percent in the glasses has caused non-linear fluctuations in the physical parameters such as density and molar volume. Urbach energy measurements and optical band gaps have shown modest inflections with In2O3composition. The 2B1g→ 2B2gtransition is responsible for the broad distinctive absorption band seen in optical absorption spectra caused by the Cu2+spin probe. The spin-Hamiltonian parameters’ non-linear variation with indium oxide content suggests that the ligand field strength surrounding Cu2+ions in glass samples has changed. Bonding parameter values are determined using EPR and optical absorption spectrum data, and it is discovered that they are ionic in nature. According to FTIR tests, when the amount of indium oxide in the glass grew, a small percentage of BO3units were converted into BO4units. Indium oxide in these glasses appears to generate notable modifications in the electrical conduction, transparency, and semiconducting behavior, according to the behavior of their optical, physical, and spectroscopic qualities.

In this study, MgO–BaO–B2O3–Fe2O3glasses were synthesized using the conventional melt and quench method, and the role of BaO and MgO in dictating their structural, physical, and optical properties was investigated. The fast neutrons, electrons, and heavy charged radiation transmission abilities of the glasses were delineated with the aim of evaluating their capacity to act as radiation insulators. The density of the glasses decreased from 3.40 g/cm3to 2.89 g/cm3as the MgO content increased. Also, the obtained optical bandgap increased from 1.90 eV to 2.20 eV with the increase of MgO in the MBBFe glasses. The stopping powers of electrons vary from 1.39 to 11.01 MeVcm2/g, 1.41–11.37 MeVcm2/g, 1.43–11.69 MeVcm2/g, 1.44–11.87 MeVcm2/g and 1.46–12.05 MeVcm2/g for glasses with MgO contents of 0 (MBBFe0), 5 (MBBFe1), 10 (MBBFe2), 12.5 (MBBFe3), and 15 (MBBFe4) mol%, respectively. Generally, the increase in the MgO content of the glasses led to increased mass stopping powers of the protons, alpha particles, and carbon ions. The replacement of BaO with MgO compromised the thermal neutron interaction probabilities of the present glassy specimens. The MBBFe-0 glass had the best thermal neutron interaction cross sections. The fast neutron removal cross-section of the glasses was within the range of 0.1037–0.1070 cm−1with MBBFe-3 having the highest value and MBBFe-4 the least. The increase in the BaO suppresses photon buildup within the glass system. The MBBFe-glasses displayed good physical and optical properties, photon and neutron shielding abilities, which makes them attractive for diverse shielding and optical functions.

Stainless steels such as ferrritic, austenitic, martensitic and duplex stainless steels are well known for their corrosion resistance to varying extents. Among these, austenitic stainless steels exhibit superior corrosion resistance and better ductility for formability. Therefore, the ability to give simple to intricate shapes in this grade of steel brings their potential for a wide range of applications. However, the meta-stable austenite in AISI 304 is known to undergo a strain induced martensitic (SIM) transformation during conventional rolling at room temperature. This strain induced martensite causes reduction in ductility and limits formability of stainless steel. Therefore, wavy rolling technique was developed to strengthen the stainless steel through microstructural refinement. In the current study, wavy rolling with 1.5 mm amplitude was conducted on 1 mm thick stainless steel sheet to different cycles ranging from 1-4. These rolled samples were characterized by optical and Atomic Force Microscopy (AFM) with resolutions down to the nanolevel. This AFM tool is in a position to bring out the details of grain refinement and topographical roughness emerging from crystalline and microstructural defects like orientation, precipitation, stacking faults, deformation bands, slip lines and shear bands with progress in rolling as referred by the number of rolling cycles here. The structural development is semi-quantitatively related to the degree of deformation and its effect on tensile properties during wavy rolling cycle. Keywords: Structural properties; Roughness; Deformation; Wavy rolling.

Micro and Nano Features of Microstructural Properties along with Micro-Cracks and Voids, which Severely Affect the Strength and Toughness of the Material, Were Studied in Commercial EN9 Steel Round Product by Using Atomic Force Microscopy (AFM). this Has Overcome the Limitations of Optical and Scanning Microscopy. the Aim of the Present Work Is to Characterize the Pearlite Matrix Properties for Nanoscale Results as Pearlitic Morphology and Lamellae Play a Significant Role in Influencing the Mechanical Properties. it Is Also Shown that the Atomic Force Microscope Is a 3D Characterizing Tool which Can Facilitate Visualizing the Adjacent Corners in Alternate Layers of Ferrite-Cementite Lamellae. it Is Also Noted that the Micro-Sized Cracks Exist at the Weak Interfaces between the Ferrite and Cementite Lamellae, which Would Limit the Work Hardening Property of Pearlite and Thus Reduce the Ultimate Tensile Strength Significantly. in Addition, Phase Transformation from γ-Phase to Pearlite Was Schematically Predicted and Discussed as Evident from Microstructural Characterization.

The continuous use of heavy metal contaminated sewage sludge as a fertilizer can result in transfer and accumulation of toxic metals from sludge to soil. The subsequent uptake and accumulation of metals in the edible parts of vegetative tissue results in a direct pathway into the human food chain. Speciation study has great importance for monitoring the entry of heavy metals into the human food chain as these are associated in a variable manner in different phases (or species). To assess the extent of heavy metal contamination of soils and also of the vegetables grown on soil amended with sludge, speciation studies were carried out using BCR sequential extraction scheme proposed by European Commission. The vegetables that were grown on sludge amended agricultural fields were analyzed for toxic heavy metals to assess the extent of uptake of heavy metals by different plants. This study reflects the extent of contamination of soil and vegetation due to application of sludge as manure and element transfer to the human food chain.

Most of the title compounds (VII) exhibit moderate antibacterial activities, but only compound (VIIc) possesses moderate antifungal activities.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.