Kazi Nazrul University (KNU) is a Public university in Asansol, West Bengal. The university has been named after the poet Kazi Nazrul Islam. The university was established under the Kazi Nazrul University Act, 2012. Assent of the Governor was first published in the Kolkata gazette, extraordinary 16 August 2012.
The linear coordination polymers (CPs){[Mo2(DIppF)2(mu-EE'CC6H4CEE')]}infinity (EE' = OO, 2; OS, 3; SS, 4; and DIppF = N,N'-di(2,6-diisopropylphenyl)formamidinate) have been synthesized by reacting [Mo2(DIppF)2(mu-Cl) {Cl2Li(OEt2)}] (1) and potassium terephthalate or potassium dithioterephthalate or piperidium tetrathioterephthalate in dry THF-methanol mixed solvent. These are the first examples of linear CPs integrated with formamidinate supported quadruply bonded dimolybdenum units. The crystal structure of CP 2, established by Xray diffraction study, shows that the redox active trans-[Mo2(DIppF)2]2+ units equatorially linked via terephthalate ligands to form the one dimensional chain. The spectroscopic (UV-Vis-NIR, NMR) and electrochemical (CV, DPV) properties of the CPs are reported. Density functional theory (DFT) studies rationalize that the HOMO-LUMO energy gap, which is attributed to metal-bridging ligand interaction, decreases from 2 to 4 and thus responsible for electronic interaction among [Mo2] units. This work expands the synthetic foundation of linear CPs with tuneable redox and charge transport properties in quadruply bonded dimetal frameworks.
Hydraulic stowing using fly ash offers a sustainable alternative to river sand but is limited by slow settling and drainage during early placement. This technical note evaluates the influence of small gypsum additions (0–6 wt
A key aspect of large scale mining is an accurate identification of rocks and ores. This study focuses on classifying various rock types, including igneous (basalt, granite), sedimentary (coal, limestone, sandstone, shale), and metamorphic (marble, quartzite), along with ores such as iron (hematite, magnetite, limonite, siderite), copper (chalcopyrite), aluminum (bauxite), and lead (galena). Data are collected from various locations in India. The classification process involves two steps: grain boundary detection using cellular automata (CAs) and classification using convolutional neural networks (CNN). A proposed cellular automaton (CA) based algorithm enhances grain visibility and generates refined images that serve as input to the CNN models. Two CNN models, referred to as Model-I and Model-II, are proposed for rock and ore classification, respectively. To enhance feature extraction and improve classification accuracy, a self-attention module is incorporated before the fully connected layer in Model-II. Comparative analysis shows Model-I achieves high accuracy for rock classification (97.8
Concrete overlays are widely adopted as a rehabilitation strategy to restore structural capacity and extend the service life of deteriorated flexible pavements. The structural performance of such composite systems is governed by the mechanical interaction between overlay and substrate, interface bonding condition, and thermo-mechanical stresses developed under traffic loading. This study presents a mechanistic structural response based methodology for determining the required thickness of cement concrete overlay placed over an in-service bituminous pavement. The existing pavement structure is transformed into an equivalent elastic foundation system using back-calculated effective modulus of subgrade reaction derived from ASTM-based correlations. The overlay thickness is determined by equating combined wheel load induced bending stress and temperature-induced warping stress with the flexural capacity of concrete. Both bonded and unbonded interface conditions are analytically modelled to evaluate composite action and stress transfer mechanisms. Results indicate that interface bonding significantly enhances load-sharing behaviour and reduces required overlay thickness. Unbonded overlays require substantially greater thickness due to reduced composite stiffness and increased tensile stress demand. Overlay thickness increases with slab panel size and temperature differential, while improved subgrade strength reduces thickness requirement. The proposed method shows good agreement with IITPAVE simulations and established recommendations of NCPTC and ACI guidelines, demonstrating its reliability as a mechanistically consistent alternative approach for concrete overlay design.
The progressive depletion of high-grade hematite necessitates the utilisation of lean-grade resources through innovative beneficiation and ironmaking routes. In this research, tailings from a tungsten mine, e.g. lean-grade hematite ore, were upgraded via jigging and statistically optimised using a Box-Behnken design to evaluate the effects of particle size, pulsation frequency, and time on total grade recovery. Due to extensive and progressive mining, most tungsten deposits have been depleted, leaving behind vast quantities of tailings that now represent a potential lean-grade hematite resource. Quadratic regression models with high coefficient of determination (R2 > 0.95) accurately predicted process outcomes, while ANOVA confirmed that particle size and pulsation frequency were the dominant factors. Response surface analysis revealed optimum conditions that maximised iron recovery with minimal silica and alumina contamination. The optimised concentrate underwent carbothermic reduction and smelting, producing metallic iron with uniform microstructure confirmed by XRD, FESEM-EDAX, and FTIR. Finer particle size (75 mu m), higher temperature (1050 degrees C), and longer duration (60 min) enhanced the extent of reduction (EOR) and degree of metallisation (DOM). This integrated beneficiation-smelting route offers a sustainable pathway for efficient utilisation of lean hematite resources.
