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In a recent paper Azhar et al., (Mater. Res. Innov. ) claim to have grown a tris (thiourea) potassium barium sulphate (TTPBS) crystal, which according to them is a novel NLO bimetallic crystal. In this comment, we prove that the so called TTPBS is a dubious crystal. In addition, we show that the so called barium thiourea chloride (Raju et al Mater. Res. Innov, 2016) thiourea barium chloride (Mahendra et al Optik 2017) and calcium bis(thiourea) chloride (Anis et al Optik 2016) single crystals are all dubious materials and do not contain any alkaline-earth metal but are simply thiourea. [ABSTRACT FROM AUTHOR]

Mechanical strength of insulation paper was the key factor for the life of large oil-immersed transformer. To more accurately assess the life of the insulation paper, the aging mechanisms of transformer insulation paper were analysed and a new method using the activation energy was proposed to access the paper's life. Then the life prediction model was defined. Accelerated aging tests of transformer oil-paper insulation samples were executed under different temperatures. According to the test results, the parameters of life prediction model were found out. So, the life of insulation paper under the working condition could be calculated. In the end, an example of insulation paper life evaluation was given to illustrate the effectiveness of this method. [ABSTRACT FROM AUTHOR]

C.I. Pigment Red 48 : 2 (P.R.48 : 2) and C.I. Pigment Red 57 : 1 (P.R.57 : 1) composite particles encapsulated with three kinds of polyethylene (PE), which had different molecular chain structure, were prepared by dispersion polymerisation method. The modified pigments were characterised by Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), UV–Vis spectroscopy and chroma. The modified particles were dispersed in Isopar L : C2Cl4 = 1 : 1 and then successfully incorporated in an electrophoretic display cell, and P.R.48 : 2/high-density polyethylene (HDPE) particles, which had electron-withdrawing groups and coating materials with high crystallinity and without short-chain branches, had the best properties and their highest contrast ratio on the same device was found to be 2.67, which was better than those of pigments modified with others PE. [ABSTRACT FROM PUBLISHER]

Earlier, magnetic cellulose fibre was successfully produced by lumen loading and in situ coprecipitation methods. But never before had magnetic paper or magnetic sheets been produced from paddy straw and recycled paper as their substrates. The main properties needed to produce these green magnetic sheets are natural fibres possessing lumen, a hollow cylindrical shape along the fibres. Although magnetic particles can be introduced outside of this lumen, it interferes with inter-fibre bonding, leading to low-grade paper properties and making loading processes very crucial. This journal describes the properties of paddy straw and recycled paper in terms of lumen possession and the lumen's ability to be loaded with magnetic particles. The results obtained show that when using lumen, the loading technique is better than that using the in situ coprecipitation method, and paddy straw has better magnetic particle loading ability than recycled paper. [ABSTRACT FROM AUTHOR]

The effect of nanosilica particles on the water resistance of a polyurethane/nanosilica composite coated paper substrate was investigated. The polyurethane/nanosilica composite coating was prepared by dispersing nanosilica powder into solvent-based polyurethane using high mechanical stirring force. Paper substrate was coated with polyurethane/nanosilica composite using a Rod Mayer technique. Various compositions of polyurethane/nanosilica composite coatings on paper substrate were prepared. The total thickness of the paper coated with polyurethane/nanosilica composite was 0·3 mm. The field emission scanning electron microscopy images indicated that the presence of nanosilica has improved the surface roughness and porosity of paper substrate. The addition of nanosilica in polyurethane coating had increased the water resistance ability of the coated paper. It was demonstrated that polyurethane/nanosilica-6% shows better water resistance and exhibits better thermal stability than the nanocomposites with lower nanosilica loading. Fourier transform infrared spectroscopy result shows that there was no chemical reaction between nanosilica and polyurethane. [ABSTRACT FROM AUTHOR]

Air stable silver nanoparticles (NPs) at a high concentration (up to 0·2M) were synthesised by the reduction in Ag+ ions with glucose in cetyltrimethylammonium bromide (CTAB) solutions, for preparing nano-Ag ink applicable for direct writing on photo paper using a gel ink pen. The reaction was performed at room temperature, and the input of extra inert gas was not necessary. The UV/vis spectrum exhibited an absorption band at 413 nm, revealing the formation of Ag NPs. By the analysis of X-ray diffraction (XRD), the resultant particles were confirmed to be pure Ag with a face centred cubic structure. From the (high resolution) TEM analysis, it was found that the mean diameter of Ag NPs was 16·5 nm, and the morphology of the particles exhibited highly crystalline nature. In addition, the excess of CTAB was effective in reducing the aggregation and size of the Ag NPs and in improving their air stability. The reduced size and enhanced air stability of the Ag NPs resulted in an improved particle density upon sintering, which was mainly responsible for the increased conductivity of the Ag patterns. The resistivity of Ag patterns sintered at 160°C for 2 h was 6·8±0·8 μΩ cm, 4·2 times the bulk resistivity. A sample paper based electrode and circuits were successfully made, and all of them exhibited excellent flexibility and good conductivity, which can be used as part of some flexible electronic devices, such as triboelectronic generator, solar cells and radio frequency identification antenna, etc. [ABSTRACT FROM AUTHOR]

The graphene paper fabricated through an electrochemical exfoliation and filtration process provides high quality and massive graphene sheets in an ink form synthesised using artificial graphite as starting material. The product is mainly composed of bilayer and few layer graphene. Their lateral size can be up to >10 μm, and the quality determined by Raman spectroscopy is better than reduced graphene oxide. The cross-plane and in-plane thermal conductivity of the graphene paper can reach 5·5 and 3300 W m−1 K−1 measured by the direct method and the thermoelectric method respectively. [ABSTRACT FROM AUTHOR]

To achieve the silk transfer printing with reactive dye, novel transfer printing paper was prepared by coating the special paste. The impacts of each ingredient in the paste on the printing property of transfer paper were investigated. Results showed that hot-melt adhesive agent (soluble polyester, ES-1) influenced the extent of dye transfer during the hot-press process significantly; thickener (sodium alginate, SA), fixing alkaline agent (NaHCO3), and humectants (urea, glycerin and dicyandiamide) had their own contributing effects to the extent of dye fixation during the steaming. Optimal printing property was achieved when using the paste containing ES-1 6%, SA 3%, NaHCO3 1%, glycerin 2·5%, urea 2·5% and dicyandiamide 2%. The paste displayed a shear thinning behaviour and low thixotropy. The transfer paper had a good storing stability and can absorb the dye ink evenly and rapidly. The printed silk possessed a good colour fastness but its handle decreased slightly. [ABSTRACT FROM AUTHOR]

The forest tree had become beneficial as the major source of raw materials for paper production. However, the main concern is the dwindling forest tree resources. Fibre substitution from non-wood sources can overcome this problem. The abundance of napier grass is characterized as agro waste material, and has a high potential to become one of the substitution fibres. The objective of this work was to analyse the chemical composition of napier grass and to investigate the morphological properties of napier grass fibre. The chemical composition of the fibre was analysed by the TAPPI test method, chlorination method and Kuchner-Hoffner method. The results indicate the potential of napier grass as a fibre. The napier grass morphology showed a condensed composition of fibre structure under a scanning electron microscope. This study of napier grass indicated the suitability for promoting the green technology in developing an eco-friendly product. [ABSTRACT FROM AUTHOR]

In order to study the use of drying models in vacuum-infrared drying, an experiment was conducted to investigate the drying process of cherry pips at different temperatures of 60°C, 70°C and 80°C, drying characteristic curves were constructed and analysed using 6 types of thin layers, and effective diffusion coefficients, moisture content and activation energy were calculated. The results showed that the drying temperature has a greater influence on the drying rate of cherry pits, and the drying time decreases with increasing drying temperature. The main drying step occurs in the downward drying stage. Comparison of the fitting results of the six thin layer drying models presented in this paper showed that Wang and Singh's model fits better for cherry pips (${{\rm{R}}^2} \gt 0,9996$ R 2 > 0 , 9996) and the predicted values of the model agree well with the experimental values. These values are suitable for describing the drying characteristics of cherry pips under any conditions. T. [ABSTRACT FROM AUTHOR]

In the present work, Al-doped (0, 1, 2 and 3%) ZnO nanoparticles (NPs) are synthesised by green combustion method (GCM) using Terminalia Catappa seeds (TCS) extract as a novel fuel. For the synthesis Zinc nitrate and Aluminum nitrate are used as precursor and dopant respectively. The synthesised NPs are characterised by XRD, FTIR, UV-vi and impedance spectroscopy. The XRD analysis shows decrease in crystallite size varies between 40 to 26 nm as dopant increases. The FTIR spectrum reaffirms the formation of Zn-O bonding structure at 454.28 cm−1. UV-Vi spectroscopic studies show the optical band gap of 3.63, 3.53, 3.22 and 3.19 eV for Al doped (0, 1, 2 and 3%) ZnO NPs. Thermal analysis for the synthesised Al-doped (0, 1, 2 and 3%) ZnO nanoparticles are analysed using TGA/DTA studies. The Electrical characteristics are studied at various temperatures (50 to 350°C) by varying frequency (10 Hz to 8 MHz). In low frequency regions, dielectric constant and dielectric loss increases with rise in temperature. The constant AC conductivity is observed in lower frequencies and increases for higher frequencies for all doped ZnO NPs. ZnO NPs prepared with 2% of doping exhibit improved structural and electrical properties. Hence these ZnO NPs may be used as sensing material for vibration sensor. Highlights: This paper focus on green synthesis of undoped and Al-doped ZnO nanoparticles by combustion method. ZnO nanoparticles are synthesised using zinc nitrate precursor, Aluminium nitrate as dopant and Terminalia catappa seed extract as fuel. Effect of Al (0, 1,2 and 3%) doping on microstructural, optical, thermal and electrical properties of ZnO nanoparticles are investigated. The green synthesised doped and undoped ZnO nanoparticles exhibit hexagonal wruzite structure with high crystallinity. The FTIR spectrum reaffirms the formation of Zn-O bonding structure at 454.28 cm-1 The optical band gap is found to be 3.63, 3.53, 3.22 and 3.19 eV for 0, 1,2 and 3% of Al doped ZnO nanoparticles respectively. AC conductivity of ZnO nanoparticles is found to be increased with 2% of Al doped ZnO nanoparticles. Result shows an improved structural, optical and electrical performance for 2% Al doped ZnO nanoparticles and hence these nanoparticles are suitable material for sensors, organic light emitting diodes and liquid crystal displays. [ABSTRACT FROM AUTHOR]

In this paper, we use hydrothermal technique to synthesise the nanoparticle of praseodymium, cerium telluride (Pr0.2Ce0.5Te0.2) using 0.2 mol of praseodymium (III) oxide (Pr2O3), and 0.5 mol of cerium (III) nitrate hexahydrate (Ce(NO3)3.6 H2O) and 0.2 mol of Te(NO3)4and evaluate how varying annealing temperature influences the material's optical, structure, morphology, and electrical characteristics. The XRD pattern reveals a polycrystalline structure with 2theta angle of 8.418°, 9.644°, 11.037°, 13.824°, 16.442°, 19.151°, 22.262°, 40.938°. Corresponding to the diffraction peaks (011), (012), (111), (121), (114), (200), (211), (311) it was observed that the praseodymium cerium telluride nanoparticles display a significant nanoflake structure. It was observed that the size of the large nanoflakes decreased. When subjected to annealing, the surface energy of the material increased due to the presence of nanoparticle clusters. The nanoparticle that underwent annealing at 400°C was found to be more susceptible to agglomeration due to the strains that resulted from the high-temperature treatment. Praseodymium cerium telluride is highly absorbent, especially in the ultraviolet and blue light ranges. The unannealed praseodymium cerium telluride nanoparticles have a bandgap energy of 2.75 eV, which is observed to narrow down to a range of 2.61–2.37 eV as the temperature for annealing is increased. Research Highlight: The XRD pattern reveals a polycrystalline structure. The praseodymium cerium telluride nanoparticles display a significant nanoflake structure. The unannealed praseodymium cerium telluride nanoparticles have a bandgap energy of 2.75 eV. The bandgap energy for the annealed nanoparticles is 2.61–2.37 eV. [ABSTRACT FROM AUTHOR]

In this paper, a novel route for the utilisation of petroleum coke gasification ash in the preparation of autoclaved-aerated concrete (AAC) is presented. The waste ash along with quartz sand, cement, lime, and gypsum are used as the primary raw materials, with aluminium powder paste serving as the pore-forming agent. The effect of incorporating petroleum coke gasification ash on the dry density and thermal conductivity of the resulting AAC was investigated. The results indicate that the thermal insulation performance of AAC is significantly enhanced by reducing the thermal conductivity coefficient upon the addition of treated petroleum coke gasification ash. At a 40% ash content, the AAC exhibits remarkable performance that meet the requirements of A2.5B05 in GB 11,968-2006, with compressive strength higher than 2.5 MPa and dry density lower than 525 kg m−3. Furthermore, the study examined the optimal calcium silicon ratio after the addition of the ash, with the results demonstrating that AAC prepared with a ratio of 0.25–0.26 exhibits the best compressive strength and dry density. The present study offers a novel perspective on waste management, which carries substantial significance for both the environmental and construction industries. [ABSTRACT FROM AUTHOR]

In this paper, the optical, structural and electrical properties of pure and magnesium-doped TiO2 nanoparticles (NPs) of different cycles (2, 4, 6 and 8 cycles) were explored systematically. The magnesium-doped TiO2 was synthesised through successive ionic layer adsorption and reaction (SILAR) and deployed into dye sensitised solar cells. The effects of the MgO barrier layer was evaluated. The results show enhanced optical properties with MgO coating with a diminished band gap energy. The X-ray diffraction studies show that the anatase phase was preserved after doping and the dopant does not change the crystalline phase of the TiO2. The SEM results show well-dispersed morphology. For the device with 4 SILAR cycles of MgO, gains in open-circuit voltage, current density and simultaneous increase in efficiency were observed which is attributed to improved charge collection efficiency as electrons diffusing through TiO2 have a better chance of reaching the electrode before recombining. At greater SILAR cycles (6 and 8), losses in photocurrent caused net decrease in efficiencies. The results presented in this report implies that the modification of TiO2 with a metal oxide (MgO) can result to good photon management. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have evolved into a viable potential alternative energy source due to their cost-effectiveness and simple fabrication techniques. Despite the immense research interest attracted by PSCs, their rooftop application remains constrained by their low efficiency and hysteretic nature. To address these issues, in this paper, the introduction of silver metallic nanoparticles (AgNPs) with plasmonic effect was achieved by an experimental approach to stimulate the generation and transport of charge carriers, which subsequently results to minimal hysteresis and broadband-enhanced plasmonic devices. Due to the far-field light scattering effect, AgNPs improve the light-trapping of the devices. As a result, electrical characteristics and light absorption are significantly enhanced, leading to broadband increase in photovoltaic performance. With the introduction of one coating cycle of AgNPs, the highest power conversion efficiency (PCE) of the perovskite solar cells increases from a reference value of 4.543 to 10.856%. The fill factor (FF) of such a device was 0.650, the current density (Jsc) was 18.998 mA/cm2, and voltage (Voc) was 0.879 V. This device shows an improvement of ~139.0% in PCE, ~61.7% in FF, ~43.7% in Jsc and ~2.8% in Voc over the pristine device that lacks AgNPs. The findings of this study contribute to further insight and understanding of plasmonic PSCs by offering useful references and recommendations for PSCs with noble metal NPs incorporation. [ABSTRACT FROM AUTHOR]

The present paper attempts to fabricate the functionally graded materials (FGMs) with two dissimilar metals using Gravity Die Casting (GDC) with and without an interfacing layer. AZ91D and Al7075 alloys are used in this study as base metals. The Zn layer is used as interfacing material to prepare the FGMs. The interfacial microstructures of the said FGMs reveal α-Mg, Al5Mg11Zn4, and MgZn2 compounds. The absence of a Zn interface layer revealed harmful Al-Mg intermetallics such as Al12Mg17, Al3Mg2, and Mg5Al8. The microstructural examination reveals that the presence of the Zn interface protects the diffusion of Al particles with Mg particles. Further studies on the Zn interfacing layer increased the microhardness value, whereas FGMs without interface showed increased shear and impact strength. [ABSTRACT FROM AUTHOR]

A simple protocol for the preparation of nickel–cobaltite and graphene–nickel–cobaltite composites is described in this paper. Nickel–cobaltite-reduced graphene oxide (NiCo-RGO) nanoparticles are produced by self-combustion of urea–nitrate complexant. Graphene, as expected, inhibits the nanoparticles from clumping together. The production of complex during synthesis is confirmed by electrochemical and spectroscopic analyses of the composites. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to investigate the electrocatalytic oxidation of nitrite on a (NiCo-RGO) graphite electrode. The DPV approach demonstrated a linear range of 60–860 μM, with detection limits of 18.0 μM. For nitrite determination, the method's sensitivity was around 0.06767 μA μM−1 cm−2. Interference, stability, and repeatability were also checked on the sensor. DPV techniques were utilised to examine nitrite levels in soil and juice samples. [ABSTRACT FROM AUTHOR]

In this paper, a simple chemical method in the presence of glycine is described to fabricate the hierarchical structure of MgAl-based Layered Double Hydroxides (Gly-LDH), served as high-performance adsorbent for Methyl orange (MO). To elucidate the effect of glycine on the adsorption capacity, the MgAl-LDH intercalated with CO32- anions was also prepared by urea hydrolysis method (Ur-LDH). The as-synthesised nanostructures were characterised by X-ray diffraction (XRD), Thermogravimetry/Differential Scanning Calorimetry (TG–DSC), Fourier transform infrared spectroscopy (FTIR), and Scanning Electron Microscopy (SEM),. The results demonstrated that the glycine intercalated LDH exhibited high adsorption capacity for MO dye compared with MgAl-LDH obtained by urea hydrolysis method. Adsorption isotherm data for MO adsorption on Gly-LDH at 300 K and acidic pH fitted well to the Langmuir isotherm model with a maximum adsorption capacity of 800 mg/g. l. The sorption mechanism indicates that MO molecules could be sorbed onto Gly-LDH via electrostatic attraction, and ion exchange. [ABSTRACT FROM AUTHOR]

This paper deals with one competent light trapping structure of metamaterials embedded p-Si/n-ZnO-based thin solar cell assisted by different simulation studies. Through this article, the author exposed the credibility of ZnO as multidimensional material with dual utility to serve as anti-reflective coating with active material of this heterojunction solar cell. Additionally, dielectric metamaterial like silica nanoparticles on top of the structure enhanced the photon cultivation efficiency of the device. Further through this work, the author tries to validate the simulated structure in real world by the process of simple fabrication technique, which also offers same optical responses already given by theoretical studies. This investigation also confirms the metamaterial property of the monolayer silica nanoparticles in higher angle of incidence of light, which validates its utility in solar cell where injection of photon is needed throughout the day.. [ABSTRACT FROM AUTHOR]

In this paper, the hardness and wear properties of pure ceramic particles like silicon carbide, boron carbide and graphite are considered in micron size with the reinforced aluminium LM30 metal matrix composites. The stir casting setup is used to prepare the matrix alloy of different compositions i.e. 2, 4 and 6 % of silicon carbide, boron carbide and graphite respectively. The rate of wear in E24 steel disc is found by placing a pin over disc wear test machine under the dry condition. This paper is intended to study the hardness and wear characteristics of all the casted ceramics. The results show that hardness and wear of casted ceramics with RA-MMC has increased in loading and in unloading conditions. Further, it is proved that casting material after stir casting attains a better wear rate and hardness due to better dispersal of micro powder. [ABSTRACT FROM AUTHOR]

In the present paper, aqueous extracts ofAlchemilla Vulgaris (Aslan Pençesi) leaves have been used to prepare Fe3O4 nano-flakes accompanied by calcination at 400°C. The various properties of biosynthesised Fe3O4 nano-flakes were investigated using UV–Visible, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), X-Ray diffraction (XRD), cyclic voltammetry, thermogravimetric (TG), and differential thermal analysis (DTA) respectively. The SEM study reveals the formation of flake-like structure with a diameter of 85 nm and a thickness of 9 nm respectively. The DTA curve shows two endothermic peaks corresponding to the decomposition of organic matter and the deoxidation of FeO (Wustite) to α-Fe, respectively, and their activation energy values were found to be 5.73 and 16.43 kJ/moles, respectively. The green synthesised magnetite nano-flakes is proved to be an excellent electrocatalyst for the electro-oxidation of ascorbic acid. The effect of scan rates, the concentration of the modifier, and the analyte was also investigated. [ABSTRACT FROM AUTHOR]

The aim of the present paper is to develop of a new sol–gel synthesis route for production of phosphate-based glasses in TiO2-NiO-P2O5 systems. The structure of the prepared glasses was investigated by ICP-AES, density methods, FTIR and RAMAN spectroscopy, XRD, 31P MAS-NMR and DSC, that confirmed successful synthesis and production of phosphate-based glasses. Glasses in the TiO2- NiO- P2O5 system with a high TiO2 and NiO content of up to 12.5 mol% were synthesized in this study. XRD analysis confirms that all glass specimens with nickel are amorphous. Investigation of ternary glasses with the general formula of (70-x)TiO2-xNiO-30P2O5, whit x = 0, 2.5, 5, 7.5, 10 or 12.5 where revealed, substituting Nickel in place of titanium significantly extend the stability and prolongs the lifetime of these glasses, which opens else numerous of potential applications. [ABSTRACT FROM AUTHOR]

Single crystals L– Histidine Cadmium Bromide (LHCdBr) have been grown successfully by solution growth method. Transparent crystal was obtained in the period of 2 weeks. The single crystal X-ray diffraction shows that the crystal is triclinic in structure. Powder X-ray diffraction analysis was carried to identify the intense peak. The various functional groups present were confirmed by Fourier Transform Infrared spectroscopy. By using Energy Dispersive X-ray Spectroscopy studies presence of elemental composition was confirmed. From the optical studies the cut-off length is found to be 315 nm. The mechanical properties of the LHCdBr crystal have been analysed. The dielectric study was carried out and reported in this paper. By the Kurtz powder method the second harmonic generation was confirmed and it is 0.9 times greater than that of KDP crystal. LHCdBr shows good antibacterial activity against various standard bacterial strains (E. coli, Shigella flexneri, Salmonella typhi and Staphylococcus aureus). [ABSTRACT FROM AUTHOR]

Composites of conducting polymers with transition metal complexes (TMCs) present a fascinating combination of properties for targeted applications. This paper reports the synthesis of PPy/Octacyanotungstate composite by oxidative chemical polymerisation method. XRD and FTIR analysis confirmed the synthesis of composite and have been found to exhibit enhanced thermal stability over that of pure polypyrrole (PPy). From I-V characteristics using different models of conduction, PPy follows SCLC (space charge limited conduction) at lower voltages and as voltage increases it starts to follow Ohmic behaviour. In composite, however, the behaviour is Ohmic at lower voltages and as voltage increases exponential rise of current takes place which is consistent with Richardson Schottky or Poole Frankel model. [ABSTRACT FROM AUTHOR]

This paper describes the results of solution casting technique derived PVP polymer electrolytes with different concentrations of Fe3+ ion as the dopant. Thermogravimetric curves of the pure and Fe3+ doped PVP polymer films show three distinct steps of weight loss. X-ray diffraction patterns indicate an enhanced amorphous nature of the polymer electrolyte with the increase in dopant concentration. SEM elucidates the surface morphology of the system. The optical band gaps of the films showed a decreasing trend with increasing dopant concentration. The FTIR spectra confirmed the complexation between the Fe3+ ions and the host polymer in terms of changes in intensity and certain bands position. The maximum ionic conductivity of 5.62 × 10−8 Scm−1 at 303 K has been observed for 5 mol% Fe3+ ions doped PVP sample. Hence, the observed properties of pure and Fe3+ ions doped PVP polymer electrolytes look very desirable and promising for battery applications. [ABSTRACT FROM AUTHOR]

The paper deals with the surface modification of a heterogeneous cation-exchange membrane with the application for electrodialysis, electrodeionisation, and electrolysis. CM(H)-PP (cation exchange membrane based on polyethylene binder) membrane was covalently attached with poly(divinylbenzene-co-4-vinylbenzylchloride). We have achieved better properties than commercially available heterogeneous ion-exchange membranes in the field of chemical, electrochemical properties by the formation of layer. Ion-exchange capacity was determined with maximum value 2.99 meq g−1 dry matter, area resistance 9.9 Ω cm2 and specific resistance 149 Ω cm, permselectivity 93.4%. [ABSTRACT FROM AUTHOR]

Developing earth-abundant-electrocatalysts for water-splitting reactions is of great importance to curb contemporary energy demands and to address the important issues such as global warming, pollution and etc. State-of-the-art electrocatalysts (Pt, RuO2 and IrO2) remain the first choice for water electrolysis, however, their high-cost, scarcity and poor stability motivate researchers for the search of abundant, inexpensive and stable enough electrocatalysts for long-term operations. Recently nickel chalcogenides have emerged as a promising substitute for state-of-the-art electrocatalysts, owing to their excellent physiochemical aspects such as high electronic conductivity, chemical stability, specific surface area and porosity. This review paper describes the different parameters to evaluate the electrocatalytic activity, followed by different synthesis methods and strategies employed for the synthesis of nickel chalcogenides. Furthermore, this review provides an overview of some of the important investigations and developments on nickel chalcogenides for water-splitting reactions. At last, the challenges and opportunities for the future exploration of these nickel chalcogenides are put forward and discussed. [ABSTRACT FROM AUTHOR]

The g-C3N4 nanosheets, CdS NPs, and g-C3N4/CdS composite were fabricated using sonochemical method for the efficient photocatalytic degradation of CV dye, MCP pesticide and catalytic reduction of 4-NP using NaBH4 as a reducing agent. The synthesized nanocatalysts were characterized by various physicochemical techniques. The g-C3N4/CdS composite was capably degradation of CV and MCP, and catalyze the reduction of 4-NP to 4-AP in the presence of NaBH4 very efficiently with good recyclability up to five cycles than g-C3N4 and CdS NPs. Further, the temperature effect on the catalytic reduction of 4-NP using g-C3N4/CdS composites was also studied. The catalytic reduction reaction follows the pseudo-first-order kinetics. The corresponding rate constants increased with the temperature, revealing activation energy of 26.42 kJ/mol. The scavenging radicals from the antioxidant activity of the synthesized composites were determined by DPPH method. In addition, the synthesized composites showed good antibacterial and antifungal activities using paper disc method. [ABSTRACT FROM AUTHOR]

This paper aims to evaluate the influence of surface area and amount of nano silica (NS) on the performance of concrete with different water/binder (w/b) ratios. For this purpose, 63 different mixes were produced using three NS having three differentsurface areas (52, 250 and 500 m2/g) and w/b ratios (0.4, 0.5 and 0.6). Compressive strengths , workability, water absorption and the microstrcture of concrete mixtures were measured and analysed. and the optimum ratio for each type was determined. The results indicated that the performance of NS particles in concrete is significantly dependent on its amount and surface area as well as w/b ratio. As the w/b ratio increased, a better performance was observed for all types of NS used, whilst NS having 250m2/g surface area was found to be the most effective. The optimum amount of NS ranged from 2 to 5%, depending on NS surface area. [ABSTRACT FROM AUTHOR]

With the development of modern industrial production, it is difficult for a single industrial material to meet the needs of production development. Therefore, composite materials with many excellent properties appear, but because of their excellent properties, it is difficult to adopt conventional machining methods. In this paper, single-factor variable experiments of pulse width, peak current, flushing pressure and working fluid conductivity of 10% SiC reinforced aluminium matrix composite and titanium-magnesium-aluminium alloy were carried out by electrosparking machine tool to study the electrosparking properties of SiC. The results showed that the machining efficiency was improved by increasing pulse width, peak current, flushing pressure and working fluid conductivity in a certain range, and the machining efficiency tended to be stable or even decreased if the increase exceeded a certain range; the thickness of the recast layer decreased with the increase of flushing pressure, but increased with the increase of pulse width, peak current and working liquid conductivity and tended to be stable. [ABSTRACT FROM AUTHOR]

Studies were undertaken to produce reactive pozzolana i.e. metakaolin from four kaolinitic clays collected from different sources in India. This paper reports an investigation on the effect of mineralogy on the pozzolanic activity of fired kaolin clay samples. Samples are characterized by X-ray diffraction (XRD), Differential Thermal Analysis (DTA), Scanning Electron Microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) in order to determine their mineralogical composition and structural differences. Calcination of samples are carried out at 700°C and 800°C for one hour. The decomposition of kaolinite is recorded using methods of thermal analysis and FTIR. The resultant products are identified by XRD. The pozzolanic activity of the thermally treated samples is evaluated based on electrical conductivity. Pozzolanic activity of metakaolinite is strongly related to the crystallinity of the original kaolinite. Well-ordered kaolinite is transformed into less reactive metakaolinite. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study of the effects of surface modification and fibre types on the stabilisation of kaolin slurry. A pre-mixed solution of cationic surfactant – cetyltrimethylammonium chloride (CTAC), selected after preliminary screening based on the knowledge of the substrate, have been used for the surface modification of kaolin prior to stabilisation with different types of synthetic polypropylene (PP) fibres. The results show an improvement in the shearing resistance of kaolin when stabilised with different types, proportions, and lengths of fibres. At higher fibre content, there is an increase in the shearing resistance of the fibre-stabilised kaolin composites for the three categories of fibres tested. Furthermore, the shearing resistance of the CTAC-PP fibre composites converges as the confining stress increases from 160kPa to 480kPa. In general, the shearing resistance of surface modified kaolin stabilised with 5% fibre length is slightly higher than corresponding composites containing unmodified kaolin. [ABSTRACT FROM AUTHOR]

The paper considers a way of iron nitrides production in monolithic specimens. The relevance for iron nitrides production is conditioned by the promise in using phase Fe16N2 (α"-phase) as a hard-magnetic material due to the high value of the saturation magnetization (2.3 T at 4.2 K). By means of X-ray diffraction analysis, scanning electron microscopy, and magnetic parameter measurements, the study analyzes the structure and magnetic properties of metal alloy based on iron, obtained as a result of interaction between iron and boron nitride powders after their mixing, pressing, and heat treatment at 1550°C in the atmosphere of nitrogen. The heat treatment results in metal fragments exudation from the ceramic part of the briquette. The microstructure of the fragments is composed of primary deposited iron, eutectic colonies of Fe – iron boride type, and incorporation of iron nitrides. The obtained metal fragments are characterized by high coercivity (0.50 kOe). [ABSTRACT FROM AUTHOR]

Europium doped yttrium silicate phosphor material has been prepared using combustion method for large scale production. For this material, the emission characteristics, crystallite size and morphology have been analysed through PL, XRD and FE-SEM respectively. The prepared material belongs to the structure of α-Y2Si2O7 which is confirmed by XRD analysis and its average crystallite size found to be 37 nm. From PL analysis, the excitation peaks are observed at 260, 321, 363, 379, 384, 396, 412 and 416 nm. The broad band is centred at 260 nm is known as charge transfer band (CTB). Moreover, the emission peaks are observed at 579, 587, 590, 598, 612, 615, 620 and 699 nm. From the ratio between the intensity of magnetic and electric dipole transition (I587 nm and I620 nm), the preferred site of Eu3+ has been discussed in this paper. The relation between Eu3+ concentration and PL intensity is also discussed [ABSTRACT FROM AUTHOR]

This paper deals with the systematic investigation of microstructure, optical and magnetic properties of Co doped CaSnO3 nanostructures prepared by hydrothermal route. Detailed structural analysis using XRD, FTIR and Raman analysis reveals the formation of orthorhombic CaSnO3 with pnma space group. Optical absorption studies authenticates the tuning of optical band gap upto 1eV was achieved by varying Co concentration in Ca-Sn-O lattice. Presence of oxygen vacancies and defects in the grown nanostructures were supported by PL and EPR studies. Room temperature M-H loops implies clear occurrence of room temperature ferromagnetism in all the Co doped nanostructures and the saturated magnetization (Ms) increases with increase Co doping. The magnetization behaviour was explained based on F-centre exchange interactions mediated by oxygen vacancies. The overall findings open up a pathway to tune the ferromagnetism as well as bandgap of stannate systems by varying the concentration of transition metal dopant's. [ABSTRACT FROM AUTHOR]

In this paper, the effects of bentonite(Bt) loading on the performances of bentonite filled acrylonitrile butadiene rubber (NBR/Bt) composites were reported. The cure characteristics, tensile properties, thermal properties and morphology of NBR/Bt composites were studied. As the Bt loading was increased, the curing time (t90) and scorch time (ts2) were reduced until 30 phr of Bt loading and increased with further increasing of Bt loading afterwards. However, the minimum torque (ML) and maximum torque (MH) increased with increasing Bt loading. The increasing char residue and decomposition temperature indicated an improvement of thermal properties of NBR/Bt composites with increasing Bt loading. Furthermore, the tensile fractured surface morphology of the NBR/Bt composites has shown increasing crack propagation with more surface roughness. Hence, resulted a better tensile strength, elongation at break and tensile modulus compared to the pure NBR particularly up to 90 phr of Bt loading. [ABSTRACT FROM AUTHOR]

This paper reports a method for producing α-Al2O3 at low temperatures by using a hydrothermal process and a seeding technique. White aluminum hydroxide precipitate prepared through a homogeneous precipitation method using aluminum nitrate and urea was peptized by using formic acid at room temperature to transform it into a transparent alumina sol. After the sol was hydrothermally treated, α-Al2O3 nanoparticle seeds were added to the sol. The sol containing the α-Al2O3 nanoparticles was transformed into an α-Al2O3-seeded alumina gel by drying at room temperature. The non-seeded alumina gel began to crystallize into α-Al2O3 at 500 °C. The α-Al2O3-seeding promoted the crystallization of the alumina gel to α-Al2O3. A remarkable α-Al2O3 crystallinity was achieved with an increase in α-Al2O3 content by weight in the final seeded alumina gel. Even with a content as low as 1%, the seeded alumina gel was partially crystallized to α-Al2O3 at a temperature as low as 400 °C. [ABSTRACT FROM AUTHOR]

Here and in the companion paper, the physical performance measurement, especially measurement units and physical dimensions of fractance and rules for fractors in series and parallel are discussed. The concept of fractance, as the fractional-order impedance of a fractor, arose following the successful synthesis of a fractional differentiator in an analogue circuit. Until now, however, the measurement units and physical dimensions of fractance have not been proposed. Motivated by this need, in this paper, I studied the electrical properties of fractor. In particular, the driving-point impedance function of the arbitrary-order fractor in its natural implementation is introduced. Through mathematical and physical analysis, the driving-point impedance function of the 1/2-order fractor is studied, following which the driving-point impedance function of the arbitrary-order fractor is proposed. This paper discusses fundamental issues, whereas Part II is devoted to the measurement units and physical dimensions of fractance and the rules for fractors in series and parallel. [ABSTRACT FROM AUTHOR]

Up to now, no effective physical performance measurements have been proposed for fractor, a promising circuit element, especially with regard to the measurement units and physical dimensions of fractance. Motivated by this need, in this paper, I study the physical performance measurement of fractor. In particular, the fundamental issues introduced in the companion paper (Part I) are combined with a proposal for the measurement units and physical dimensions of fractance, together with the rules for fractors in series and parallel, respectively. Through mathematical and physical analysis, I first propose the measurement units (Yi-Fei PU)−V and (Yi-Fei PU)V, for capacitive fractance and inductive fractance, respectively, as well as the physical dimensions of fractance. I then introduce the rules for fractors in series and parallel. [ABSTRACT FROM AUTHOR]

The specific property of the weathering steel is its ability to create a protective patina layer on its surface in favourable environments. The weathering steel can be used without any corrosion protection and has considerably lower corrosion rate than standard carbon steel. The analytical corrosion prediction model for the calculation of corrosion losses is introduced in this paper. Methodology and results of experimental atmospheric corrosion tests are presented in this paper as well. The paper explains the high degree of correlation dependence between corrosion losses and thickness of corrosion products on a road bridge over a railway track in the city of Ostrava. [ABSTRACT FROM AUTHOR]

The quantitative regression analysis of the mixture based on the terahertz spectrum is reported in this paper. The absorption spectrum and the refractive index spectrum of a mixture of benzoyl peroxide and polyethylene were obtained by calculation, and then a mixture of benzoyl peroxide and polyethylene was used experimentally, and then the spectrum obtained was preprocessed using the method of wavelet filter, first derivative model and second derivative model. Partial least squares regression and kernel partial least squares regression were applied to the modelling of the regression analysis of the original absorption spectrum, the first derivative model and second derivative model spectra, and a detailed performance evaluation is presented at the end of the paper. [ABSTRACT FROM AUTHOR]

In this paper, a copolymer containing photosensitive group was used as photo-alignment film through linearly polarised ultraviolet irradiation to a varying heating rate for an investigation of liquid crystal orientation. When the polymer film is exposed to linearly polarised ultraviolet, it can generate a polarisation-axis selective photoreaction. Then the thin film underwent thermally enhanced photoinduced molecular reorientation followed by subsequent annealing. Fixed exposure energy was 324 mJ cm−2 and annealing temperature was 98°C, heating rates varied from 5 to 30 S °C−1, a large anisotropy was generated. According to the method mentioned in the paper to calculate the enhanced ratio, the best heating rate is 20 S °C−1. [ABSTRACT FROM AUTHOR]

In this paper, the modified Hummers method was employed for preparing graphene oxide, which was reduced to graphene by using different reducing agents later. Meanwhile, various techniques have been performed to investigate the structure of the as-made graphene oxide and graphene. The paper aimed at improving the electrical conductivity of graphene. This work has paved the way for the future application in electrically conductive printing ink, and provided various effective measures for characterising graphene oxide and graphene. [ABSTRACT FROM AUTHOR]

Compatibility between the transformer oil and construction material should be considered in real transformer operation for equipment safety. In this study, we investigated the characteristics of the two types of naphthenic transformer oil and self-developed hydrogenated transformer oil by means of aging experiment with solid component of transformer, for instance, construction material, rubber seals, insulating varnish and insulating paper. It was suggested that the hydrogenated transformer oil performed much better in all of the compatibility tests, while the naphthenic transformer oil delivered detrimental results in rubber seal, paper degradation test and insulating varnish test. In addition, thermal stability experiment of the oil also indicated the better performance of hydrogenated oil than the naphthenic oil. This research study not only suggested the better compatibility of hydrogenated oil, but also provided the theoretical data for the potential use of hydrogenated oil in transformers. [ABSTRACT FROM AUTHOR]

Pattern recognition is a key issue in the field of textile computer aided analysis and design. Focusing on the non-stationarity of the fabric texture structure, a hybrid method combining two-dimensional mode decomposition with mean shift segmentation is proposed in this paper. Two-dimensional empirical mode decomposition is an adaptive image analysing technique, which uses intrinsic spatial scales instead of predefined basis functions to decompose a given image into a number of intrinsic modes. The first intrinsic mode preserves multiple patterns for an underlying fabric image, which is subsequently submitted to the mean shift clustering process in this paper. Simulation results have proved that the proposed mean shift algorithm in empirical mode domain is in accordance with human visual effect, and possesses the capability of clustering diverse patterns inherent in the textile in a fully unsupervised way. [ABSTRACT FROM AUTHOR]

Composite material has many advantages such as small specific gravity, high strength and good corrosion resistance. So it is widely used to the aircraft manufacturing industry. Composite material has a poor conductivity, lighting current is difficult to quickly to go out when subjected to lighting, resistance heat would cause serious heat damage and endanger the safety of aircraft flying. In this paper, the finite element analysis software is used simulate the thermal-electrical effect of carbon fibre epoxy composite plates when struck by lightning. Simulation results show that maximum potential of the composite is consistent with the trends of the exposed lighting current waveforms, lighting current goes along with the direction of the largest conductivity of the surface the composite plates, resistance heat generated by lighting current also mainly goes along the surface so that the thermal damage of the composite plate are concentrated on the surface. The thermal injury of the next layer in influenced by the angle of the upper layer. The thermal injury of the layer with 90° fibre angle is more serious, so the amount of the layer with 90° fibre angle should be as little as possible. The paper obtains the thermal damage distribution of the composite plate when struck by lighting and provides a reference for assessing the reliability of the composite exposed to lighting. [ABSTRACT FROM AUTHOR]

This paper discussed the reasons and the harms of high-speed railway's roadbed settlement in collapsible loess area. On the basis of the experimental simulation and mechanical analysis, the mechanism of fracture grouting is concluded, and a set of upper grouting test equipment is developed as well. Through a set of tests under different grouting pressures, and analyses on the soil's mechanical properties and displacement variations, a quadratic approximation formula is gained. Meanwhile, the mechanism for fracture grouting and the validity of laboratory simulation is tested and verified. In addition, the effect of fracture grouting on high-speed railway's roadbed consolidation in collapsible loess area is also got by fieldqs trial. The results of the current paper provide guide and reference for studying fracture grouting in collapsible loess area. [ABSTRACT FROM AUTHOR]

This paper discussed the reasons and the harms of high-speed railway's roadbed settlement in collapsible loess area. On the basis of the experimental simulation and mechanical analysis, the mechanism of fracture grouting is concluded, and a set of upper grouting test equipment is developed as well. Through a set of tests under different grouting pressures, and analyses on the soil's mechanical properties and displacement variations, a quadratic approximation formula is gained. Meanwhile, the mechanism for fracture grouting and the validity of laboratory simulation is tested and verified. In addition, the effect of fracture grouting on high-speed railway's roadbed consolidation in collapsible loess area is also got by fieldqs trial. The results of the current paper provide guide and reference for studying fracture grouting in collapsible loess area. [ABSTRACT FROM AUTHOR]

The objective of this experiment was to investigate the relationship between binder migration and ink penetration using atom force microscopy and laser scanning confocal microscopy. The different drying temperature was used to change binder migration. Binder migration was observed using atom force microscopy. Fluorescent ink was used to observe and characterise ink penetration and distribution by laser scanning confocal microscopy. Reconstructed images were used to describe ink penetration in the coated paper by laser scanning confocal microscopy. The results implied that it was reliable and effective using laser scanning confocal microscopy to characterise ink penetration depth and distribution uniformity. This method could not damage the specimen, and did not need fluorescent dye to stain the specimen. The results indicated that binder migration affected ink penetration depth and distribution evenness. More binder migration to the paper surface could not contribute to ink penetration and even ink absorption. [ABSTRACT FROM AUTHOR]

A new method for equivalent bending modelling of Sandwich Plate System considering the effect of adhesive proposed in this paper. The steel panel and the adhesive are equivalent to a laminated plate by using laminated plate theory, and the expressions of equivalent parameters are derived. Two equivalent methods, including the sandwich theory and the proposed method in the paper, are respectively used to build the model of Sandwich Plate System under three-point bending. According to the comparison between the numerical results and the experimental results, it is assumed that the proposed method is appropriate to study bending research of Sandwich Plate System composite steel. [ABSTRACT FROM AUTHOR]