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The purpose of this study is to investigate the effect of a horizontal web splice on a power plant ceiling girder (CG) with transverse stiffeners. Case study is conducted through two ceiling girders, viz. (1) a girder made of steel having a yield stress of 410 MPa in the flanges and end stiffeners and 250 MPa at the web and intermediate stiffeners, and (2) a girder made of steel having a yield stress of 350 MPa in flanges and end stiffeners and 250 MPa in the web and intermediate stiffeners. The design of horizontal splice is done by considering the horizontal shear at splice location, compressive force in splice flange, and various failure criteria of connectors and other elements. Design methodology followed in IS 11384: 1985, Code of practice for composite construction in structural steel and concrete, Bureau of Indian Standards Manak Bhavan New Delhi, India, 1985 and IRC 22: 2008, Standard specifications and code of practice for road bridges, section VI: composite construction (Limit State Design). (Third Revision), Indian Roads Congress, New Delhi, 2008 for composite construction is applied for the design of horizontal splice (stiffeners), which nearly provides the same design results. “Average Shear Force Method” is employed in the design of horizontal splice in CGs. Non-linear finite-element analysis was carried to identify the optimum location of the horizontal splice using the commercial general purposed finite-element analysis tool ABAQUS®. Three different locations of horizontal splice such as 0.3dw, 0.4dwand 0.5dwfrom top were considered in the analysis. Based on the numerical results, it is concluded that the horizontal splice provided at 0.5dwsignificantly enhances the ultimate load-carrying capacity, ductility and bending stiffness of the girder.

The construction sector plays a crucial part in the nation’s growth in economic and furthermore faces growing concerns about its environmental impact. To address this, the construction industry has grown interested in life cycle assessment studies as concerns about sustainability and environmental conservation improved during the past few decades. Life cycle assessment (LCA) has evolved as a striking technology for assessing the environmental impact of products and processes in their whole life cycle. As a result, to fill this gap in the literature, a thorough and comprehensive assessment of the LCAs in the subject domain is required. The review dives into the diverse applications of LCA in construction including the assessment of building materials, construction procedures, and whole structural systems. It accentuates the significance of LCA in directing preferable materials, optimizing construction designs, and informing decision-making for ecologically conscious construction practices. Furthermore, the review explores the challenges of adopting LCA in the construction industry. Besides, the paper focuses on the potential benefits of LCA implementation in the construction area. LCA supports the reduction of carbon footprints, resource consumption, and waste creation by identifying environmental hotspots and possibilities for improvement, eventually promoting sustainable construction practices, and fostering the transition to a greener built environment. This study aims to shed a spotlight on the relevant state of LCA research as well as key terms, and developing areas in the construction. The research results of this study significantly benefit both industrial professionals and the scientific community by presenting an in-depth overview of the current status, developing concepts including challenges, as well as emerging fields of LCA in the construction sector. Furthermore, researchers interested in this topic would find this study a beneficial and valuable reference and guidance.

This article reviews the various housing schemes implemented in India post-independence. This year marking the 75 years of independence, the demand for affordable housing for economically weaker sections and low-income group are at stake in the country. In achieving “Housing for all” in the rapidly urbanizing Indian context, Textile reinforced concrete (TRC) technology promises to be environmentally and economically “affordable” consuming significantly fewer quantities of building materials with high embodied energy. Textile reinforced concrete is the most durable, lightweight, and highly ductile structural component with its non-corrosive textiles replacing the conventional steel reinforcement used, and it can be the most feasible solution to the problem of implementing affordable housing in urban India. TRC has been an excellent solution for the retrofitting and strengthening of existing infrastructures paving its progressive research direction of using this as a load-bearing structural component. With a substantially lower carbon footprint than conventional RCC structures, TRC offers better potential for sustainability. Furthermore, this article proposes a futuristic direction to enhance the research on the application of TRC as a structural component for prefabricated low-cost housing.

This experimental investigation employing leaching characteristics of concrete made with E-waste plastic [high-impact polystyrene (HIPS)] was carried out using the toxicity characteristic leaching procedure (TCLP). The heavy metals, such as Cd, Cu, Zn, and Pb, were analyzed from concrete with varying percentages of HIPS (0 %, 10 %, 20 %, 30 %, 40 %, and 50 %) at various ages, such as 28, 60, and 90 days. The concentrations of Cd in the TCLP extracts of all the samples were found to be lower than the regulatory level of 1 mg/l at 28, 60, and 90 days. The Cu, Zn leachate content decreased with curing, and all samples were found well below the prescribed level of 100 mg/L and 500 mg/L, respectively. The concentrations of Pb in the TCLP extracts of all the samples were found to be lower than the regulatory level of 5 mg/L at 28, 60, and 90 days. The results are also compared with Resource Conservation and Recovery Act (RCRA) prescribed limits for Cd, Cu, Zn, and Pb, which are 0.5 mg/L, 130 mg/L, 500 mg/L, and 1.5 mg/L, respectively, and which are within limits.

Laboratory experiments were conducted to find out the efficacy of different crude extracts and fractions of Couroupita guianensis(Lecythidaceae) against Spodoptera litura(Fabricius). Results revealed that hexane, chloroform and ethyl acetate extracts of C. guianensisshowed larvicidal and pupicidal activities against S. litura. Maximum larvicidal activity (68.66%) was observed in hexane extract at 5.0% concentration followed by chloroform and ethyl acetate extracts, and least LC50value of 2.64% was observed in hexane extract. A 100% pupicidal activity was observed in hexane extract. Based on the efficacy of crude extracts, the effective crude extract (hexane extract) was further fractionated and subjected to screening for biological activities against S. litura. Among the eight fractions isolated from the hexane extract, fraction 8 showed maximum antifeedant activity (81. 8%) and larvicidal activity (76.9%) at 1000-ppm concentration; this fraction showed least LC50value of 375.92 ppm for larvicidal activity. Cent per cent pupicidal activity was recorded. Reduced midgut and hemolymph protein contents were observed at 1000 ppm of fraction 8. Histopathological studies revealed that fraction 8 severely damaged the midgut cells of S. litura. This fraction could be used to develop botanical formulation to control agricultural pests.

Pure and Co-doped gallium nitride (GaN) (5 and 8 mol%) nanocrystals were synthesized by nitridation of Ga–EDTA.NH4and Co–Ga–EDTA.NH4complexes. Pure and 5 mol% cobalt-doped GaN did not show any impurity phases in the X-ray diffraction and Raman analysis, whereas 8 mol% Co-doped GaN show secondary phase formation. Transmission electron microscopic study revealed the broad crystal size distribution ranging from 10 to 140 nm. Cathodoluminiscence spectra measured at 20 K shows the suppression of GaN band edge emission with increasing Co concentration. Magnetic measurements of Co-doped GaN revealed a ferromagnetic behavior up to room temperature. The saturation magnetization value increases with increasing impurity phase separation. X-ray photoelectron spectroscopy revealed evidence on the oxidation states of cobalt and excludes the possibility of Co clusters in the doped samples.

ZnO nanostructures were deposited on GaN (0001), Al2O3(0001), and Si (100) substrates using a high-pressure pulsed laser deposition (PLD) method. Vertically aligned hexagonal−pyramidal ZnO nanorods were obtained on the Al2O3and Si substrates whereas interlinked ZnO nanowalls were obtained on the GaN substrates. A growth mechanism has been proposed for the formation of ZnO nanowalls based on different growth rates of ZnO polar and nonpolar planes. Both ZnO nanorods and nanowalls exhibit a strong E2Hvibration mode in the micro-Raman spectra. The corresponding fluorescence spectra of ZnO nanorods and nanowalls showed near band emission at 3.28 eV. The ZnO nanorods grown on the Si substrates exhibited better crystalline and optical properties compared with the ZnO structures grown on the GaN and Al2O3substrates. The high aspect ratio, good vertical alignment, and better crystallinity of the ZnO nanorods with tapered tips exhibited promising field emission performance with a low turn-on field of 2 V/μm, a high current density of 7.7 mA/cm2, and a large field enhancement factor.

The paper is concerned with the tension field action in webs of steel-concrete composite plate girders. A three-dimensional finite element model has been used to carry out nonlinear analyses on composite plate girders. The results obtained from the finite element analyses are compared with those from experiments. It is observed from the comparative study that the proposed nonlinear finite element model is capable of predicting the ultimate load behaviour of steel-concrete composite plate girders to an acceptable accuracy. Results are presented to explain the development of the tension field action in the webs and to illustrate a measure of the contribution by the concrete slab acting compositely with the girder to the changes in tension field compared to a plain steel girder.

Lattice parameter calculations and ice nucleation studies for the Agl-Cul-Kl system are reported. Using the vacuum fusion method, samples of different compositions were prepared. The formation of cubic solid solution for these samples was confirmed by X-ray diffractograms. It was found that the solid solution of Agl, Cul and Kl having the mol % composition of 60:20:20 has the highest nucleation temperature, -1.70° C, far greater than the nucleating temperature of pure Agl, Cul and Kl.

The crystallinity and solar cell efficiency of Al0.22Ga0.78As layers grown on Si substrates have been studied by varying the thermal cycle annealing (TCA) temperature. The optimum TCA temperature to obtain an Al0.22Ga0.78As layer with long minority carrier lifetime and high conversion efficiency has been presented. The active-area conversion efficiency of an Al0.22Ga0.78As solar cell on a Si substrate as high as 10.2% has been obtained under AM0 and 1 sun conditions.

The concentration of arsenic atoms from Ga + Bi mixed solvent has been calculated in the range of 0.4 to 100 at% of bismuth for different saturation temperatures corresponding to the cooling rates of 0.32, 1 and 10 K min—1 at a constant equilibrium temperature of 1023 K using appropriate boundary conditions. It has been observed that the thickness of the epitaxial layer for 0 to 20% of bismuth has been found to be very high due to the immiscible region. The change in arsenic concentration in the mixed Ga–Bi–As solution has been observed to be dependent on the bismuth composition and compared with our theoretical values. The simulated layer thickness value agrees well with the experimental results obtained by the authors.

The liquidus isotherms for the Ga-As-Bi system were determined at 973 and 923 K in the Ga-As-GaAs region. The liquid phase epitaxial growth of GaAs from Ga-As and Ga-As-Bi solutions were investigated. The addition of ten atomic percent of Bi to the Ga-As solution increase the growth rate of the grown epilayers nearly 4.4 times than in the case of GaAs layers from Bi solution. Above 9 at.% of Bi in Ga solution the problems associated with the edge growth were almost eliminated. Optical measurements at 4.2 K revealed that Bi does not alter the band gap energy value of the GaAs epitaxial layers. The photoluminescence (PL) intensity and full width at half maximum (FWHM) revealed the good quality of undoped GaAs epilayers from Bi solvents compared to that of Ga solvents even though the purity of the Bi was relatively less.