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Bamboo fibres, which are widely regarded as a contemporary environmentally sustainable resource, have been utilised in various industries including construction materials and packaging sectors. Malaysia possesses a diverse array of bamboo species, rendering it a significant resource for exploration. Five out of the 69 bamboo species discovered in Malaysia were selected for their suitability and availability in the pulp and paper industry, considering properties such as high cellulose content and long fibers. The objective of this study is to conduct a comprehensive analysis of the morphological, physiochemical, thermal, and chemical properties of five specific bamboo species that are often found in Malaysia: Gigantochloa scortechinii (GS), Gigantochloa wrayi (GW), Gigantochloa levis (GL), Schizostachyum grande (SG) and Dendrocalamus asper (DA). Selected from a pool of 69 species based on their availability, these various types of bamboo were subjected to analysis using advanced scientific techniques such as Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), and X-ray Diffraction (XRD). Furthermore, a chemical composition study was performed to clarify the presence of cellulose, hemicellulose, lignin, and ash in all five species. By employing various analytical methodologies, this study investigates and records the properties offered by the bamboo species, providing a significant contribution to the comprehension and knowledge of their potential applications across diverse disciplines. This holds relevance as all five bamboo species are readily available but remain underutilized for further applications in various fields especially in packaging industries. [ABSTRACT FROM AUTHOR]

Background: Researchers, prompted by the toxicity and side effects associated with cisplatin, are exploring alternative approaches for developing transition metal-based anticancer agents. Employing a green biochemical approach, we transformed Nickel pyridine dicarboxylic acid compounds into the nanoscale using the aqueous extract of Macrotyloma uniflorum (horse gram). Results: Characterization of the biosynthesized nanoparticles involved electronic and IR spectroscopy. A scanning electron microscope revealed a predominant spherical shape for most Nickel nanoparticles (Ni-NPs), with XRD patterns indicating particle sizes ranging from approximately 30–150 nm. The nanoparticles were evaluated for their free radical scavenging efficiency and in vitro anti-malignant properties against HeLa and A549 cancer cell lines. Numerical optimization of the DPPH and MTT assays was conducted using response surface methodology (RSM), focusing on the effects of 3,4-pyridine dicarboxylic acid (ML1), 2,4-pyridine dicarboxylic acid (ML2), nickel nanoparticles concentration, and temperature. In this investigation, the incorporation of Horse Gram seed extract (Macrotyloma uniflorum) has unveiled its abundance in phenolic and flavonoid compounds, widely acknowledged for their robust antioxidant activity in the existing literature. Conclusion: The present study highlights the potential for refining the bio-toxicity and biochemical attributes of Ni-NPs to pave the way for a new generation of versatile anticancer agents with clinically established efficacy. Notably, the anticipated data closely corresponds with experimental outcomes, reinforcing the trustworthiness and validity of the RSM model for examining anticancer and antioxidant properties in this context. ML2 exhibited heightened antioxidant and anticancer activities in comparison to ML1 nanoparticles. [ABSTRACT FROM AUTHOR]

In order to enhance storage capacity and prevent electrical short circuits in electrochemical storage devices, it is essential and challenging to design and build Lithium ion batteries with flexible solid polymer electrolyte possessing strong ionic conductivity. This study details the use of solution-cast technique to create nano composite doped lithium solid polymer electrolytes (n-LSPEs), from polymer complex of poly (vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP), polyethylene oxide (PEO), and Lithium trifluoromethanesulfonate (LiCF3SO3), with nano ZrO2 (n-ZrO2). Electrochemical impedance spectroscopy (EIS) was utilised to describe the ionic conductivity values in presence of alternating fields. The ionic conductivity of n-LSPEs are enhanced nearly four times (1.54 × 10─1 mS/cm to 5.996 × 10─1 mS/cm) due to addition of n-ZrO2. By incorporating chronoamperometry (CA) and cyclic voltammetry (CV), we were able to analyse the transference number, ionic strength, and the accumulation of charge carriers in optimized n-LSPE membrane. Scanning electron microscope (SEM) images of n-LSPE membranes reveal a structure that is consistent with interconnecting pores between the polymer complex and the nano filler. The stable monoclinic phase of n-ZrO2 interaction with polymer segmental motion was confirmed by X-ray diffraction (XRD). By examining Fourier transform infrared spectroscopy (FTIR), we performed a quick analysis of the complexation of functional group investigations, bond length and force constant calculations, interaction of functional groups of n-LSPE films. Our FESD's discharge characteristics were investigated at 4.8 mA average discharge current for 25 hours, as indicated by a 0.04C rating. [ABSTRACT FROM AUTHOR]

This study deals with WC-12Co coatings deposited by cold spraying on 13Cr4Ni steel hydraulic turbine blades. The coatings were deposited under different pressure conditions such as 25, 30, 40 bar at 800 °C, and 50 bar at 900 °C. The microstructural evolution under different pressure conditions and the effect of temperature variation were investigated using a scanning electron microscope (SEM) equipped with energy-dispersive x-ray spectroscopy (EDS) and x-ray diffraction analysis (XRD). In addition, the microhardness analysis of the coatings showed that the WC-12Co coating deposited at 40 bar 800 °C had the highest (270 HV) hardness which was a good attribute for anti-wear applications in hydraulic turbine blades according to most tribological theories. [ABSTRACT FROM AUTHOR]

Nanoparticles of tin oxide (SnO2) doped with iron oxide (α-Fe2O3) and Europium oxide (Eu2O3) were synthesized through the solid-state synthesis method. The phase analysis confirms the tetragonal rutile phase for all samples using X-ray diffraction (XRD). The luminescence intensity and expansion of lattice depend on doping percentage, which validates the successful blending of Fe and Eu in SnO2 lattice. The lattice dislocation and strain are calculated using the Williamson–Hall (WH) parcel, which also supports the development of the grain boundary in the doped samples. An increase in a large number of recombination centers leads to quenching in optical spectra by using the photoluminescence (PL) spectrum, and the shift in the band gap estimated from UV–visible absorption spectra confirms the impact of the grain boundary. A vibrating sample magnetometer (VSM) under the physical properties measurement system (PPMS) confirms room temperature ferromagnetism RTFM, and a scanning electron microscope (SEM) showed clear images of grain boundaries. Conductivity studies show an increase in resistance to Fe/Eu doping. Among all the tailored samples, Sn(1−x)Fex/EuO2, for x = 0.04 wt. % and 0.02 wt. % proved as a potential candidate for magneto-opto-electronic, i.e., spintronics device applications. [ABSTRACT FROM AUTHOR]

Dried sandstone slurry (DSS) is generated during mining and processing of stone and is accounted as man-made hazardous waste material, contaminating the environment in nearby areas. The use of DSS in self-compacting concrete (SCC) was studied by partially substituting pozzolana Portland cement at different percentages. This represents the recycling element of the 3 R's of the environment (reduce, reuse and recycle). Mechanical and permeability properties were evaluated and the microstructure of SCC analysed with respect to a control mixture which is without sandstone slurry. Mechanical and permeability parameters were found to relate each other. With increased replacement of DSS, the porosity and hence the sorptivity coefficient of SCC also increased and its compressive strength decreased. The higher porosity caused a significant increment in the depth of carbonation. Scanning electron microscope (SEM) and X-ray diffraction (XRD) showed decreased calcium-silicate-hydrate (C–S–H) gel formation as the replacement percentage of DSS increased. This, along with the increased porosity and permeability, degraded the mechanical properties of SCC. The rapidly developing construction sector in India must meet the following indispensable criteria: low environmental impact at improved structural performance, economy and speed of construction. Utilization of sandstone waste is highly recommended from the above viewpoint. [ABSTRACT FROM AUTHOR]

The diminution of the natural sources in the form of dredging the riverbanks and blasting the mountain ranges has always dented the balance of the ecosystem which in turn results in disasters as well at times. This alarming situation accelerates the global warming, threatens the biota life in riverbanks, diminishes the ground water level, harms the aquatic life, and affects the growth of agriculture. This study is an attempt to synthesis fine aggregates from the industrial byproducts, namely, fly ash and GGBS through the process of geopolymerization. This enables the formation of aluminosilicate networks upon the addition of the alkaline activator solution (Na2 SiO3 + NaOH) into the byproducts. The dry mix is then allowed for oven drying as well as air drying to accelerate the geopolymerization process. The fly ash-geopolymerized fine aggregate (F-GFA) and the GGBS-geopolymerized fine aggregate (G-GFA) were noted to exhibit adequate physiochemical and mechanical properties in par with the natural sand. The production of GFA is considered eco-friendly process since it ceases the extensive usage of river sand and incorporates the effective usage of industrial byproducts (fly ash and GGBS), thereby minimizing the land pollution and its consequent harmful hazards. Though the F-GFA and G-GFA showcased higher water absorption ratio than the natural sand due to the presence of unreacted fly ash and GGBS particles, the complete replacement of fine aggregate with geopolymerized sand initiated the adequate compressive strength attainment up to 90% of natural sand, by reacting with the lime expelled out of the hydration process of cement in the mortar specimens developed in this experimental study. The geopolymer itself is hydrophilic in nature, and it will also aid for the higher water absorption ratio of the polymer sand. The microstructure of the samples was further examined through optical microscope, scanning electron microscope, and X-ray diffraction analysis in order to corroborate the experimental results of this study. The results thus obtained strongly recommend the potential of the F-GFA and G-GFA as an ideal replacement material for natural sand. [ABSTRACT FROM AUTHOR]

Poly(p-phenylenediamine- co–o-aminophenol) nanostructure thin film [PpPDoAP]TF was synthesized and prepared as a thin film with ≅ 100 ± 2 nm using the spin-coating method. Different characterization techniques for [PpPDoAP]TF like FTIR, UV–Vis spectroscopy, and optical properties have been studied. The resulted x-ray diffraction (XRD) and scanning electron microscope (SEM) data have been employed to study interface composites. Density function theory (DFT) was used for optimization by DMol3 and CASTEP. Spectroscopic and structural characteristics for the thin film have confirmed the chemical composition and XRD observations revealed the same crystal structure. Combined between experimental and TDD-DFT data, the average crystallite size and composite interface are 71.87 nm and orthorhombic symmetry (a = 7.38(2); b = 18.09(6); c = 26.09(4) Å and α = β = γ = 90°) with space group (Pmcn) for the thin film. It is found that the calculated energy gap by DFT and experimental method are 2.523 and 2.504 eV, respectively. The electronic transition of [PpPDoAP]TF has direct allowed transition. Besides, the optoelectrical parameters have been calculated for the film like n(λ), k(λ), dielectric constant, and optical conductivity. CASTEP simulated values are consistent with the experimental values for optical parameters of [PpPDoAP]TF. The fabricated thin film can be used as a candidate material for optoelectronic devices and solar cells. [ABSTRACT FROM AUTHOR]

The authors reported the data found by FT-IR spectroscopy, ultrasonic velocities, DTA investigations of 5Al2O3 – 25Li2O – (70 − x) P2O5 – x TiO2, (0 ≤ x ≤ 25 mol%) of the prepared glass samples. From FT-IR spectroscopy has been indicated the titanate doped phosphate glasses increase the produce of non-bridging oxygens. By ultrasonic velocities has been indicated that these velocities are decreased as well as elastic-moduli and density by the concentration of titanate. This behaviour due to decreasing the density, cross-link density, and increase in molar volume. By DTA the values of (Tg), (Tc) and (Tp) decrease this is due to a decrease the bond strength. A parent glass–ceramics of these glasses have been prepared, and investigate by XRD and SEM. The parent glass–ceramic of these glasses have been prepared and investigate by XRD. Li2P2O6 (lithium orthophosphate) crystalline phase is showed in glasses-free titanate and transformed into LiPO3 in glasses containing titanate. The surface morphology of glass–ceramic has been checked by scanning electron microscope and showed a nearly unchanging surface in glasses-free titanate and large interstitial pores in glasses containing titanate. [ABSTRACT FROM AUTHOR]

Glass samples with the compositions xFe2O3-35SiO2-35B2O3-10Al2O3-(20 − x) Na2O (0 ≤ x ≤ 1 mol.%) were designed and assembled by melting quenching technique. These samples were investigated by XRD, optical, mechanical, thermal, and FT-IR spectroscopy studies. FT-IR spectra reveal that these glasses are built up of BO3, BO4, and octahedral [FeO6]. The present glasses exhibited the increase in density, thermal parameter values, ultrasonic velocities, elastic moduli, optical band gap (Eopt), and refractive index of the prepared glasses. The corresponding glass-ceramic of these glasses was prepared by controlling heat treatment and investigated with XRD, mechanical, SEM, and TEM. The present glass-ceramics exhibited the increase in density, ultrasonic velocities, and elastic moduli; these values are larger than those of the parent glasses. XRD exhibited the crystalline phases of selected glass-ceramics samples. The transmission electron microscope (TEM) exhibited the grain size of glass-ceramics in nano-size and range between 63.9 and 165 nm. The scanning electron microscope (SEM) exhibited backscattered electron images of the produced glass-ceramics. It is observed that crystalline texture contains relatively large interstitial pores, demonstrating the residual glassy matrix. [ABSTRACT FROM AUTHOR]

In this present work, we have focused on the effect of cobalt substitution in the nickel aluminate system. The aluminate samples were synthesized by the chemical precipitation method. The structural and optical properties of the NiAl2O4, CoAl2O4, and Ni0.5Co0.5Al2O4 samples were studied through X-ray diffraction and UV-DRS absorbance spectral analysis. The XRD pattern confirms the cubic phase with the space group of Fd-3 m through its analysis of the diffraction peaks. The UV absorption peaks around at 360, 480, 551, 580, and 621 nm extend the formation of NiAl2O4, CoAl2O4, and Ni0.5Co0.5Al2O4 system. The surface morphological images of the samples were scanned by using the scanning electron microscope. The room temperature magnetic nature of the aluminate samples was carried out using VSM, and the observed result reveals a weak ferromagnetic and super-paramagnetic nature for NiAl2O4 and Ni0.5Co0.5Al2O4, respectively. The temperature dependence impedance spectra and AC conductivity were measured using an impedance analyzer at selected temperatures, and that reveals the bulk resistance of the grain and the grain boundary region of the sample. The observed results were analyzed and discussed. [ABSTRACT FROM AUTHOR]

The paper presents the effect of liquid polymer on the geotechnical properties and microstructure of two fine-grained soil. Commercially available liquid polymer was used to stabilize a commercially available soil (Soil I, type ML) and natural soil (Soil II, type CH). Various physical properties test has been conducted to characterize the soils. The liquid polymer was mixed at various percentages (i.e. 2, 3, 4, and 5%) on dry weight basis. The polymer-stabilized soil samples were cured for 7, 14, and 28 days under confined and open-air environment. Unconfined Compressive Strength (UCS) test and California Bearing Ratio (CBR) test were conducted to evaluate the strength of polymer-stabilized soil. The results show that with the addition of polymer; UCS value for ML samples prepared at its OMC increases up to 75% in open-air environment and up to 14% in confined air environment. CH soil samples prepared at its OMC shows cracks while curing in open-air environment and there is no significant change of strength in confined air environment. For CH soil UCS samples were prepared with reduced moisture contents and cured in open air environment shows increase in UCS strength up to 10%. CBR test results shows that there was marginal increase (i.e. 14%) in CBR value for CH soil but a significant increase (i.e. 340%) in CBR value for ML soil. X-ray diffraction test was conducted for ML and CH to determine the mineralogical composition of virgin and liquid polymer-stabilized soil. It was observed that, no new minerals were formed with the addition of polymer. Scanning electron microscope test was also conducted to analyze the microstructure of the virgin and polymer-stabilized soils. [ABSTRACT FROM AUTHOR]

This paper characterizes the sugarcane bagasse ash as a pozzolan and investigates its influence on the hardened properties of concrete. In Pakistan, the sugar industry recycles raw bagasse for power generation, and as a result, tonnes of bagasse ash are produced every year. For this study, the bagasse ash sample was obtained from one of the local sugar mills of Pakistan. The physical, chemical and mineralogical of bagasse ash were investigated by employing X-ray diffraction (XRD), X-ray fluorescence and laser particle size techniques, while the microstructure was studied through scanning electron microscope. In addition, the evaluation of hardened properties like compressive strength, tensile strength, flexural strength and thermal conductivity was also carried out. Here, the concrete mixtures were prepared by replacing the cement with bagasse ash in the ratio of 5 to 30% (by weight). The chemical, physical and mineral results reveal that this local bagasse ash has all pozzolanic properties. The evidence of amorphous and crystalline phases was found in the XRD pattern, along with silicon dioxide (SiO2) which was recorded more than 70% in the ash. It was observed that the workability for bagasse ash-blended concrete mixtures increases with ash content. Furthermore, the bagasse ash mixtures with 10% substitution were found optimal for achieving higher compressive, flexural and tensile strength, while the thermal conductivity showed a consistent drop with higher ash content percentage. [ABSTRACT FROM AUTHOR]

The aim of this study was to find appropriate precipitation conditions (Ca/P ratio, pH and precipitation rate) for the synthesis of hydroxyapatite (HAP; Ca10(PO4)6(OH)2) and to determine the effect of precipitation conditions on its thermal behavior. Hydroxyapatite was synthesized by precipitation. Three ratios of Ca/P (1; 1.67; 3) were selected for the synthesis, then pH 7 and 12 was selected, and the ammonium dihydrogen phosphate precipitation rate was set to 2 mL min−1. The prepared powders were studied from the standpoint of particle size distribution, crystal size and morphology (optical microscope, scanning electron microscope), phase composition (X-ray diffraction analysis) and thermal stability in relation to the Ca/P ratio. [ABSTRACT FROM AUTHOR]

Physical aspects of tobacco samples, used in some commonly available Indian brands of cigarettes, with emphasis on their magnetic characterization before and after they get burnt into ashes, are described. The present work highlights the ultrafine nature of the cigarette ashes and provides a compositional insight of their constituent particulate matters as revealed by the XRD and SEM studies. Based on the EDX spectra, elemental distributions of different tobacco samples, before and after they get burnt, are presented. In this work, magnetic measurements of the un-burnt tobacco samples are reported. An attempt is made to shed light on the origin of magnetism observed in these samples. [ABSTRACT FROM AUTHOR]

This paper presents the results of an experimental investigation on performance of fly ash-based geopolymer pastes at elevated temperature exposure. Geopolymer paste specimens having Si/Al in the range 1.7-2.2, manufactured by activating low calcium fly ash with a mixture of sodium hydroxide and sodium silicate solution were subjected to temperatures up to 900 °C. The effect of Si/Al ratio was studied on the basis of physical appearance, weight losses, residual strength, volumetric shrinkage and water sorptivity at different temperatures. Scanning electron microscopy along with energy dispersive X-ray and X-ray diffraction analysis were also conducted to examine changes in microstructure and mineralogy during the thermal exposure. Specimens gradually changed in colour from grey to light red accompanied by the appearance of small cracks as the temperature was increased to 900 °C. Loss of weight and volumetric strain due to elevated temperature exposure were higher in specimens manufactured with lesser Si/Al ratios. Geopolymer paste specimen containing maximum Si/Al of 2.2 performed best in terms of residual compressive strength after exposure to elevated temperatures. [ABSTRACT FROM AUTHOR]

This paper reports the liquefied petroleum gas (LPG) sensing of titanium dioxide (Qualigens, India). Scanning electron micrographs and X-ray diffraction studies of samples were done. SEM shows that the material is porous and has grapes-like morphology before exposure to the LPG. XRD patterns reveal the crystalline nature of the material. The crystallites sizes of the TiO were found in the range of 30-75 nm. Variations in resistance with exposure of LPG to the sensing element were observed. The average sensitivity for different volume percentages of gas was estimated. The maximum value of average sensitivity was 1·7 for higher vol.% of LPG. Percentage sensor response (%SR) as a function of time was calculated and its maximum value was 45%. Response time of the sensor was 70 s. The sensor was quite sensitive to LPG and results were found reproducible. [ABSTRACT FROM AUTHOR]

Higher productivity is registered with Flux cored arc welding (FCAW) process in many applications. Further, it combines the characteristics of shielded metal arc welding (SMAW), gas metal arc welding (GMAW), and submerged arc welding (SAW) processes. This article describes the experimental work carried out to evaluate and compare corrosion and its inhibition in SA 387 Gr.22 (2.25Cr-1Mo) steel weldments prepared by FCAW process with four different heat inputs exposed to hydrochloric acid medium at 0.1, 0.5, and 1.0 M concentrations. The parent metal, weld metal, and heat-affected zone are chosen as regions of exposure for the study carried out at 100 °C. Electrochemical polarization techniques such as Tafel line extrapolation (Tafel) and linear polarization resistance (LPR) have been used to measure the corrosion current. The role of hexamine and mixed inhibitor (thiourea + hexamine in 0.5 M HCl), each at 100 ppm concentration is studied in these experiments. Microstructural observation, hardness survey, surface characterization, and morphology using scanning electron microscope (SEM) and x-ray diffraction (XRD) have been made on samples to highlight the nature and extent of film formation. The film is found to contain Fe2Si, FeSi2, FeMn3, Fe7Mo3, Fe3O4, FeO, FeCr, AlO7Fe3SiO3, and KFe4Mn77Si19. [ABSTRACT FROM AUTHOR]

Coal is an important fuel used in boiler furnaces. There are problems like unburnt coal and solid wastes like ash contain arsenic, selenium, chromium and cadmium while using it. In order to avoid all such difficulties, aluminium metal powder in various grain sizes mixed with pulverized coal and burned. aluminium metal powder is one of the pyrotechnics having higher calorific value and low ignition temperature. The thermal behavior of aluminium powder along with coal is recorded in DTA. The collected ashes were tested in Scanning Electron Microscope and X-Ray Diffraction meter. The SEM results show that coal ash is having granular and regular structure. All the particles have a size range from 5 to 8 μm. On the other hand, the aluminium coal mixture ash shows a fibrous matrix and the particles are irregular. In XRD graph, the peaks in the graph show orientation of atoms in particular plane and angle. The coal ash has a lot of peaks, but the maximum count value reaches only to 340.97. However the value of counts reaches a maximum of 1,539.06 for aluminium ash. This denotes high atom orientation in a single lattice plane. [ABSTRACT FROM AUTHOR]