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In this research, the study of two dopants, strontium oxide and manganese oxide were thoroughly investigated based on the elastic properties for the purpose of high strength glass application. The melt quenching technique method was used to synthesize two series of borotellurite glass systems doped with manganese and strontium. Elastic measurement, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the prepared glass samples. The increment of molar volume confirmed the theory that molar volume is inversely proportional to the density parameters. A broad hump was observed during XRD as the samples shows pure amorphous nature. In FTIR, the vibrations of the functional group of the tellurite network were recorded such as TeO4 trigonal bipyramids and TeO3 trigonal pyramids, by addition of both dopants. On the other hand, ultrasonic velocity was used to determine the elastic moduli of the glass such as bulk modulus, shear modulus, longitudinal modulus, Young’s Modulus, microhardness and Poisson’s ratio which showed decreasing and increasing trends with the increased concentration of MnO2 and SrO respectively. It is also inferred that strontium oxide has better elastic properties than manganese oxide.

This work presents the effect of erbium oxide in tellurite glass on the intensity parameters, emission and upconversion to be used as laser glass. We select 0.04 mol fraction of erbium oxide in tellurite glass as it gives the optimum results for glass stability, luminescence and intensity parameters. The structural arrangement of glass matrices was revealed by XRD analysis. The amorphous structural arrangement was found and there was no crystalline structure existed in the glass matrix. The FTIR analysis revealed the existence of TeO3 non-bridging oxygen which has important role in the shifting of the optical parameters. The Judd–Ofelt analysis (intensity parameters, Ωλ = 2, 4, 6) were studied by applying nine transition states obtained from UV–Vis-NIR absorption spectrum which were 4G11/2 + 2H9/2 + 4F5/2 + 4F7/2 + 2H11/2 + 4S3/2 + 4F9/2 + 4I9/2 + 4I11/2. The obtained results for the intensity parameters were in accordance by the following trends Ω2 > Ω4 > Ω6. A broad red emission at 648 nm was found with excitation state of 380 nm. Four emission peaks were found from upconversion emission spectrum as follows; 381 nm, 420 nm, 466 nm and 560 nm which correspond to 4G11/2 → 4I15/2, 4F3/2 → 4I15/2, 4F7/2 → 4I15/2 and 4S3/2 → 4I15/2. The prominent emission for upconversion was 560 nm which produce yellow emission. Based on these results, erbium doped boro-tellurite glass is capable to be utilized as red, blue and green glass lasers. The absorption and emission cross sections and optical gain factor have been carried out by using Mc-Cumber theory.

A system of bio-silica borotellurite glasses was fabricated based on the chemical formula [(TeO2)0.7 (B2O3)0.3]1-x (SiO2)x with x = 0.1, 0.2, 0.3, and 0.4 using the melt-quenching technique using silica (98.548% SiO2, from rice husk), TeO2 (Alfar Aeser, 99.9%) and B2O3 (Alfar Aeser, 99.9%). Measurements and characterizations such as density and molar volume measurements, XRD analysis, FTIR, and UV–Vis spectroscopes were performed on the studied glasses. The objective was to determine the glasses’ applicability in optoelectronics, non-linear optics, and laser technologies through polarizability, linear electric susceptibility, and optical basicity study. Apart from confirming the amorphous nature of the glasses, the XRD analysis identified the presence of a crystalline phase of tellurium oxide (α-TeO2) formed. The FTIR spectral study revealed the presence of TeO3, BO3, and SiO4 structural units in the studied glasses. The refractive index (2.3026 – 2.2651), molar polarizability (8.0696 – 9.4334 A3), oxide ion polarizability (3.2970 – 3.6202 A3), electronic polarizability (0.2296 – 0.2335 A3), dielectric constant (5.1307 – 5.3019), optical basicity (0.6719 – 0.7998), metallization criterion (0.410853 – 0.420714) and electric susceptibility (0.3286 – 0.3422 esu) of the glasses were presented. With the high refractive index and favourable electronic/oxide ion polarizability as well as good electric susceptibility, the glasses have shown great potential for optical fibre and laser applications. Metallization criterion value falls in the range of glasses with great potentials for non-linear optical application. The dielectric value suggests the glasses represent wideband semiconducting glasses believed to be good for application in microelectronic substrates fabrication.

Carbon-based materials such as graphene oxide are known as attractive candidate to improve the current optoelectronic and laser devices. In this work, neodymium nanoparticles doped zinc-tellurite glass coated with graphene oxide (GO) denoted as ZBTNd (NPs)-GO was prepared via low-cost melt-quenching method and simple spray coating method. The structural properties of the glass system had been carried out by using X-ray diffraction (XRD) and confirmed its amorphous structural arrangement with non-existence of crystalline structure. The TeO3 and BO3 structural units were found dominant in tellurite glass network as determined by Fourier transforms infrared spectrometer (FTIR). High number of oxygen functional groups and stacked of graphene layers on the glass surface were revealed by field scanning electron microscopy (FESEM) and Raman spectroscopy. The optical band gap energy values were found to decrease in the range of 2.665–2.405 eV along with dopant concentration. In the meantime, the refractive index values were found more than n > 2.00 and fall in the range of 2.12 to 2.20. The electronic polarization was calculated by using Lorentz-Lorentz equation and found in the range of 6.516 to 7.211 A 3. Based on these results, the improvements on optical properties of tellurite glass have been made to be used in laser application.

Peat is commonly described as a soil that is possess to high rate of compressibility due to present of high organic substance derived from plant origins. Peat soil naturally associated with settlement and consolidation characterized by its high initial void ratio, organic content and water holding capacity. This paper presents the performance of peat soil treated with powdered melamine urea formaldehyde resin (MUF-P) in term of compression and consolidation behaviour under standard compressibility test. In this study, series of one-dimensional oedometer test were carried out with the load increment method from 12.5 to 400 kPa after 24 hours of each loading. Peat soils under high moisture condition were mixed with MUF-P within 3 days of stipulated periods of curing times. The results indicate that increasing the MUF-P proportion has improved the compressibility characteristics of peat soil. The result shows the values of compression index (Cc) decreased from 4.12 to 0.9, and secondary compression index (Cα) were also decreased from the range of 0.026 to 0.320 to the range of 0.080 to 0.161 with the increase of peat MUF-P proportions up to maximum 350 kg/m3.

The DC conductivity of Eu3+ ions embedded in lead boro-tellurite glasses has been accomplished as a function of temperature in the range of 343–483 K. The Cole-Cole (Impedance) plots of glasses contained only one perfect semicircle at different temperatures. This realizes the material's conductivity which presumes an ideal Debye type relaxation. In the Cole-Cole plot at 483 K, the semicircle is well defined and fitted into an equivalent parallel RC circuit. The DC conductivity exhibits the Arrhenius behavior and compositional dependence. The DC activation energy (Edc) was estimated for all samples by using linear regression analysis. The values range from 0.202 to 0.231 eV.

The disposal of non-biodegradable synthetic plastic wastes is linked with air, land, and marine pollutions. Incineration of plastic wastes released toxic substances into the air while recycled plastics end up accumulated in landfill and dumped into the ocean. In this study, novel sugar palm starch reinforced with sugar palm crystalline nanocellulose was blended with poly(lactic acid) (PLA) with various formulations to develop alternative materials potentially substituting conventional plastics. X-ray diffraction analysis demonstrated broad amorphous scattering background with minor diffraction peaks at 2θ of 19.4° and 22° associated with VH-type and B-type crystal structure for all blend bionanocomposites samples. Higher solubility rates were observed for PLA20TPS80 (96.34%) and PLA40TPS60 (77.66%) associated with higher concentration of plasticizers providing extra space in the polymer chains to be penetrated by water molecules. Increasing PLA content was not necessarily enhancing the water vapor permeability rate. Dynamic mechanical analysis presented a significant increment in storage modulus (E′) for PLA60TPS40 (53.2%) compared to the trivial changes of PLA70TPS30 (10%) and PLA80TPS20 (0.6%). However, significant improvement in impact strength occurred only at PLA40TPS60 (33.13%), and further addition showed minor improvement between 12 and 20%. Overall, it is noted that PLA60TPS40 demonstrated adequate functional properties to be used in food packaging application.

Soft soils pose abundant engineering issues due to its low bearing capacity and shear strength. Comprehensive study on soft soil’s physical properties such as shear strength and ability to store water (porosity) could help in devising the optimum ground improvements and foundations techniques. Therefore, physical properties of soft marine clay in Nibong Tebal were thoroughly studied using 2-Dimensional Resistivity Imaging (2-DRI) method in conjunction with porosity measurements, standard penetration test values (SPT-n) and particle size distribution (PSD) analysis. The 2-DRI profile depicts three lithologies, which are unsaturated topsoil, saturated soft clayey soil and saturated sandy soil in the area. The soft soil extends up to 32 m in thickness where it overlies the sandy layer and could be correlated back to lithology profile from borehole record. Additionally, soil samples were collected at three locations along the survey line for porosity measurements via saturation porosimetry method. The samples demonstrate that the clay layer has a very large porosity range and signifies that the soil will compress tremendously under load. On the other hand, SPT-N values of the soft clay is also very low; thus, could be classed as very soft to soft cohesive soil with very low shear strength as compared to a higher range SPT-n values of the sandy layer. The PSD result also compliments the 2-DRI, porosity and SPT results to show distinct differences between topsoil and the soft clay layer in terms of the presence of fine grains. These results further indicate that the thick upper layer is not capable of bearing immense loads such as high-rise infrastructures due to the soil’s high porosity and low shear strength. Hence, the area must undergo ground remediations prior to any infrastructure developments on the land.

Introducing a zinc stannate, ZnSnO3 (ZTO), layer on hydrothermally grown 3D-zinc oxide (ZnO) nanosheet thin films has been proven to have a quenching effect on the photoluminescence emissions, indicating very slow recombination of photoinduced electron-hole pairs in photoelectrochemical water splitting (PEC) reactions. Motivated by this, the ZnO/ZTO bilayer system has been used as the electron transport layer for copper indium gallium sulfide (CIGS)-based photoelectrodes in PEC applications. Furthermore, the poor photoresistivity of CIGS has been improved via indium sulfide (In2S3) deposition. Consequently, the photoelectrode obtained from the inverted configuration, ZnO/ZTO/CIGS/In2S3, has generated a photocurrent density of 6.4 mA cm-2 at 0.4 V (vs Ag/AgCl), exceeding the performance of ZnO NS/CIGS/In2S3 photoelectrodes by three folds. The highest ABPE and IPCE efficiencies have been calculated as 4.2% and 57%, respectively. More importantly, two cost-effective nonvacuum techniques for large-scale thin film fabrications such as chemical bath deposition (CBD) and ultrasonic spray pyrolysis (USP) methods have been adopted to acquire photoelectrodes with inverted configurations providing an advantageous approach for low-cost photoelectrode design for sustainable energy production. Copyright © 2020 American Chemical Society.

The melt-quenching method was used to synthesize a series of neodymium-doped zinc tellurite glass systems. The ultrasonic velocities, elastic moduli and other elastic parameters of the prepared glasses showed non-linear variations with an increase of Nd2O3 in the glass system. The non-linear variation is associated with the presence of non-bridging and bridging oxygen caused by the network modifier of Nd2O3. Theoretical data sets for the elastic properties of the glass systems were obtained by using the Makishima and Mackenzie theory and the Rocherulle, bond compression and ring deformation models. The values retrieved for the elastic moduli by using the Makishima and Mackenzie, and Rocherulle models are in great agreement with the corresponding experimental data. The recorded bond compression model data for the glass has much higher values for elastic moduli when compared to the corresponding experimental values. Therefore, in this glass system, only the bond compression model is not favoured.

[(TeO2)0.7(B2O3)0.3]1-x (BaO)x, x = 0.00, 0.05, 0.10, 0.20, 0.25, 0.30 and 0.35 mol fraction glass series were successfully synthesized by conventional melt quenching method. Amorphous phase of all samples was confirmed through X-ray diffraction while optical properties were determined using UV-VIS spectrophotometer. Fourier Transform Infrared (FTIR) analysis showed that the glass structure consisted of TeO3, TeO4, TeO6, BO3 and BO4 structural units. The optical band gap energy, Eopt which was calculated from Tauc’ plots decreased as the amount of BaO increases, whereas, the Urbach energy value increased. The increase in Urbach energy value was attributed to the increase of defects in glass structure. The refractive indices of glass were found to increase along with the increased amount of BaO, due to the high polarization and high density of host material and glass modifier. The molar polarizability, αm, oxide ion polarizability, αo2- and optical basicity, Λ of the glasses are calculated by Lorentz-Lorenz equation. The glasses were found to possess αm values between 8.106 – 8.489 Å3, and αo2- values between 3.303 to 4.772. Meanwhile, optical basicity increases from 0.115 to 0.893.

In this paper, the spectroscopic characteristics of two series of TeO2–B2O3 glass systems which were successfully synthesized using the conventional melt quenching method were investigated. The compositions of these two glass series are: [(TeO2)70 (B2O3)30]100-x (Bi2O3)x, and [(TeO2)70 (B2O3)30]100-x (BaO)x,. The effects of adding Bi2O3 and BaO on the structural and optical properties of the glass system were studied. The results demonstrate that the boron–boron separation decreases as the Bi2O3 and BaO content increases, as the glass modifier has a higher molecular weight than the glass network TeO2–B2O3. The shifts in the absorption peak shown in the FTIR spectra are dependent on the glass composition. The analysis shows that the structural units, TeO3, TeO4, TeO6, BO3 and BO4, are found in the glass sample. The optical band gap energy, Eg, calculated from Tauc’s plots, decreases as more Bi2O3 and BaO are added. In contrast, the Urbach energy value rises, implying that more defects exist in the glass structure. Both the absorption edge shift into higher wavelength and the decrease in the Eg values were attributed to the restructuring of the glass network and modifier. The shift was also enhanced by the progressive increase in the concentration of non-bridging oxygen atoms. Due to the high polarization and density of the host material and glass modifiers, the refractive indices were also observed to increase with higher content of Bi2O3 and BaO. Despite the fact that the results of the two glasses showed relatively similar trends, the study concluded that Bi2O3 glass is preferable for photonic applications.

In the present work, a thermal treatment technique is applied for the synthesis of CexSn1−xO2 nanoparticles. Using this method has developed understanding of how lower and higher precursor values affect the morphology, structure, and optical properties of CexSn1−xO2 nanoparticles. CexSn1−xO2 nanoparticle synthesis involves a reaction between cerium and tin sources, namely, cerium nitrate hexahydrate and tin (II) chloride dihydrate, respectively, and the capping agent, polyvinylpyrrolidone (PVP). The findings indicate that lower x values yield smaller particle size with a higher energy band gap, while higher x values yield a larger particle size with a smaller energy band gap. Thus, products with lower x values may be suitable for antibacterial activity applications as smaller particles can diffuse through the cell wall faster, while products with higher x values may be suitable for solar cell energy applications as more electrons can be generated at larger particle sizes. The synthesized samples were profiled via a number of methods, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR). As revealed by the XRD pattern analysis, the CexSn1−xO2 nanoparticles formed after calcination reflect the cubic fluorite structure and cassiterite-type tetragonal structure of CexSn1−xO2 nanoparticles. Meanwhile, using FT-IR analysis, Ce-O and Sn-O were confirmed as the primary bonds of ready CexSn1−xO2 nanoparticle samples, whilst TEM analysis highlighted that the average particle size was in the range 6−21 nm as the precursor concentration (Ce(NO3)3·6H2O) increased from 0.00 to 1.00. Moreover, the diffuse UV-visible reflectance spectra used to determine the optical band gap based on the Kubelka–Munk equation showed that an increase in x value has caused a decrease in the energy band gap and vice versa.

The melt-quenching method was employed in order to fabricate a series of erbium-doped and silver-doped zinc tellurite glass systems with the chemical composition of [(TeO2)0.7 (ZnO)0.3]1−x (Er2O3)x and [[(TeO2)0.7 (ZnO) 0.3]0.96 (Er2O3)0.04]]1−y (Ag2O)y at different molar fraction of x and y = 0.01, 0.02, 0.03, 0.04 and 0.05. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, density and optical measurements were utilized to characterize the provided glass samples. At room temperature, all the results of XRD, FTIR, density and optical properties are tabulated respectively. An amorphous nature of glass samples is proven by the XRD spectra for both glass series. The analysis of FTIR spectra displays the existence of functional vibration of tellurite network. It is observed that the density of both glass system increases with the addition of dopants into the glass system. In erbium-doped glass series, the value of molar volume is found to be directly proportional to the density. This in turn results in the creation of excess free volume due to the difference of bond length between erbium and tellurite. As in the case of silver-doped glass series, it is observed that the value of molar volume is inversely proportional to the density. The optical properties of the prepared glasses were identified by UV–VIS analysis. The optical absorption spectra reveal the fundamental absorption edge for both glass series which shifts to higher wavelength as the content of dopants increases. The values of direct and indirect band gap decrease while the Urbach energy and refractive index of erbium-doped zinc tellurite glass are viewed to increase as the concentration of dopants is included in the glass sample. This may be due to the presence of non-bridging oxygen within the vitreous network of the glass sample. Meanwhile in silver-doped glass series, the band gaps are found to be non-linearly decreased while the Urbach energy and refractive index are viewed to be non-linearly increased when the concentration of dopants are added into the zinc tellurite glass system. As a whole, the trends for respective parameters can be correlated to the presence of non-bridging oxygen within the vitreous network of the glass sample.

Self-compacting concrete (SCC) refers to high strength concrete which will compact under its own weight and does not require external vibration. This paper gives a review on the journals to study the effect of metakaoiln in SCC. The metakaolin is used as a replacement of cement and it is obtained from natural Kaolin clay. Metakaolin helps to increase the compressive strength, spilt tensile strength, flexural strength and also the fresh properties. The use super plasticizer greatly improves pump-ability and the slump value. GLENIUM B233 is a new generation based super plasticizer which is based on modified polycarboxylic ether. The fresh properties such as pump ability and workability and the durability properties of super plasticizer in SCC with metakaolin are discussed. Keywords: Self-Compacting Concrete, Metakaolin, GLENIUM B233, Superplasticizer, Polycarboxylic Ether

This study reports a seeding-layer free synthesis of nanostructured three-dimensional zinc oxide (3D-ZnO) thin films via a simple and cost-effective chemical bath deposition method (CBD) followed by their sensitization with inorganic perovskite halide semiconductors for luminescence-based applications. The emission abilities of pristine ZnO nanostructures have been enhanced with the incorporation of CsPbBr3 in the cubic crystal phase, which is proven to be a highly stable member of the inorganic halide perovskite family. Additionally, the transformation of CsPbBr3 nanocrystals into Cs4PbBr6–CsPbBr3 composite structure has been attained by altering the (i) CsBr content and (ii) crystallization temperature during the perovskite synthesis step, resulting in a remarkable luminescence increase for the overall structure by ~17 folds. A detailed evaluation of defect contents and carrier lifetimes of pristine and perovskite deposited ZnO thin films have been conducted via time-resolved photoluminescence spectroscopy showing an improved electron transfer especially for Cs4PbBr6–CsPbBr3 deposited ZnO thin films.

Recently, many scientists and polymer engineers have been working on eco-friendly materials for starch-based food packaging purposes, which are based on biopolymers, due to the health and environmental issues caused by the non-biodegradable food packaging. However, to maintain food freshness and quality, it is necessary to choose the correct materials and packaging technologies. On the other hand, the starch-based film’s biggest flaws are high permeability to water vapor transfer and the ease of spoilage by bacteria and fungi. One of the several possibilities that are being extensively studied is the incorporation of essential oils (EOs) into the packaging material. The EOs used in food packaging films actively prevent inhibition of bacteria and fungi and have a positive effect on food storage. This work intended to present their mechanical and barrier properties, as well as the antimicrobial activity of anti-microbacterial agent reinforced starch composites for extending product shelf life. A better inhibition of zone of antimicrobial activity was observed with higher content of essential oil. Besides that, the mechanical properties of starch-based polymer was slightly decreased for tensile strength as the increasing of essential oil while elongation at break was increased. The increasing of essential oil would cause the reduction of the cohesion forces of polymer chain, creating heterogeneous matrix and subsequently lowering the tensile strength and increasing the elongation (E%) of the films. The present review demonstrated that the use of essential oil represents an interesting alternative for the production of active packaging and for the development of eco-friendly technologies.

Numerous studies have explored the behaviors of ZnO–TiO2 nanoparticles resulting through various routes of fabrication. To date, the utilization of thermal treatment method to convey ZnO–TiO2 nanoparticles has never been considered. In the present study, binary (ZnO)x(TiO2)1−x NPs were effectively blended by using thermal treatment technique. Zinc nitrate and titanium(IV) propoxide with polyvinylpyrrolidone, PVP, were utilized to set up the samples. Energy-dispersive X-ray (EDX) spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction (XRD) spectroscopy, ultraviolet–visible (UV–Vis) spectrophotometer transmission electron microscopy (TEM) and photoluminescence spectroscopy were utilized to examine the impact of changing the molar proportion to the structure and optical features of (ZnO)x(TiO2)1−x NPs. The XRD spectra revealed that after calcination, the amorphous sample had transformed into crystalline nanoparticles. The prepared (ZnO)x(TiO2)1−x NPs average diameter was around 25.922–28.531 nm according to TEM analysis. The analyzation of UV–Vis spectroscopy determined the optical measurements parameters including the energy gap and Urbach energy of binary (ZnO)x(TiO2)1−x NPs. The optical energy gap varied in the range of 3.2496–3.2863 eV as the molar ratio increases from x = 0.24 to x = 0.72. The enhancement within the nanoparticles optical properties suggests a good potential for photocatalysis application.

In this paper, flexible and deployable double-sided linear-to-circular polarizers designed on polydimethylsiloxane are proposed for the first time to the best of our knowledge. ShieldIt textile is used as the conducting element of the two designs based on two different unit cell arrays: a loaded circular patch unit cell or an unloaded circular patch unit cell, both backed by a generic rectangular element on its reverse side. This is in contrast to conventional frequency-selective structure-based linear-to-circular polarizers implemented using rigid substrates, which are multi-layered and requires inter-layer physical spacing. This complicates their implementation using flexible substrates and in a deployable format. Upon implementation of this double-sided polarizer, their final performances are evaluated in terms of the phase difference, conversion efficiency, 3-dB axial ratio (AR), and ellipticity bandwidth (from 40° to 45°). Measurements indicated good agreements with simulations, and both structures exhibited more than 90% of conversion efficiency from 2.34 to 3 GHz (for the loaded circular unit cell) and from 2.36 to 3 GHz (for the unloaded circular unit cell). In terms of ellipticity, a bandwidth of 8.67% is observed for the unloaded design and 13.82% for the loaded design. The unloaded structure exhibited a fractional 3-dB AR bandwidth of 36.36% (from 1.98 to 2.86 GHz) in simulations, and 32.64 % (from 2.00 to 2.78 GHz) when evaluated experimentally. Conversely, the loaded design showed only 12.58%. An equivalent circuit model is proposed and validated via a comparison between the circuit and full-wave simulations. Finally, the performances of these polarizers are also assessed under different bending conditions due to the use of flexible materials, prior to the proposal of a suitable deployment mechanism.

Synthetic plastics are severely detrimental to the environment because non-biodegradable plastics do not degrade for hundreds of years. Nowadays, these plastics are very commonly used for food packaging. To overcome this problem, food packaging materials should be substituted with "green" or environmentally friendly materials, normally in the form of natural fiber reinforced biopolymer composites. Thermoplastic starch (TPS), polylactic acid (PLA) and polybutylene succinate (PBS) were chosen for the substitution, because of their availability, biodegradability, and good food contact properties. Plasticizer (glycerol) was used to modify the starch, such as TPS under a heating condition, which improved its processability. TPS films are sensitive to moisture and their mechanical properties are generally not suitable for food packaging if used alone, while PLA and PBS have a low oxygen barrier but good mechanical properties and processability. In general, TPS, PLA, and PBS need to be modified for food packaging requirements. Natural fibers are often incorporated as reinforcements into TPS, PLA, and PBS to overcome their weaknesses. Natural fibers are normally used in the form of fibers, fillers, celluloses, and nanocelluloses, but the focus of this paper is on nanocellulose. Nanocellulose reinforced polymer composites demonstrate an improvement in mechanical, barrier, and thermal properties. The addition of compatibilizer as a coupling agent promotes a fine dispersion of nanocelluloses in polymer. Additionally, nanocellulose and TPS are also mixed with PLA and PBS because they are costly, despite having commendable properties. Starch and natural fibers are utilized as fillers because they are abundant, cheap and biodegradable.

The utilization of indium sulfide (In2S3) photo-electrodes in an all-vanadium photoelectrochemical redox flow battery system has been investigated. The In2S3-based photo-electrodes have been prepared via the ultrasonic spray pyrolysis (USP) method. The thickness of the In2S3 photoelectrodes has been altered via increasing the pass number of the USP nozzle from 25 to 75 passes. Each pass delivers 6 mu L.cm(-2) of the precursor solution. Within the scope of the photoelectrochemical oxidation on the In2S3, the vanadium couples of VO2+/V3+ have been proven to be promising redox species. The maximum charge separation and quantum efficiencies of 46% and 20% have been calculated, respectively.

This chapter contains sections titled: 1. Introduction 2. Chalcopyrite I?III?VI2 Semiconductors 3. Cu?Based Kesterite (I2?II?IV?VI4) Semiconductors 4. Concluding Remarks

In this research, the melt-quenching method was used to synthesize a series of zinc tellurite glass systems doped with erbium oxide with the chemical composition of [(TeO2)0.7 (ZnO)0.3]1−x (Er2O3)x at different molar fraction, x = 0, 0.01, 0.02, 0.03, 0.04 and 0.05. X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, density, molar volume, elastic and optical measurements were used to characterize the prepared glass samples. At room temperature, the result of the XRD, FTIR, density, elastic and optical properties were all recorded. An amorphous nature of glass samples is proven by the XRD spectra. The analysis of FTIR spectra shows the presence of functional vibration of tellurite network. It is observed that the density of the glass system increase with the molar fraction of Er2O3. The value of molar volume is found to be directly proportional to the density. Thus, the increment in the density value causes the increment of the molar volume due to the increase of erbium concentration. This in turn results in the creation of excess free volume due to the difference of atomic radius between erbium and tellurite. On the other hand, ultrasonic velocity was used to determine the elastic moduli of the glass systems. The elastic moduli such as longitudinal modulus, shear modulus, bulk modulus and Young's modulus give a fluctuating trend against the concentration of Er2O3. The increase of the elastic moduli is due to the mix former effect. In contrast, the decrease of the elastic moduli is due to the breakdown of Er2O3 in the zinc tellurite glass system which weakens the glass structure of the ternary tellurite system. The optical properties of the prepared glasses were determined by UV–vis analysis. The optical absorption was recorded at room temperature in the wavelength ranging from 220 nm to 800 nm. The optical absorption spectra reveal that fundamental absorption edge shifts to higher wavelength as the content of erbium oxide increase. The values of direct and indirect band gap have been calculated and are observed to decrease with the increase content of erbium oxide. However, the Urbach energy, refractive index, molar refraction and electronic polarizability are shown to be increased with an addition content of erbium oxides.

An improved understanding of the grain growth kinetics in Erbium-doped Barium Titanate (BTE), has attracted great interest in its applications in photonic and electronic devices. To study the effects of doping and thermal treatment on the physical properties of films, the chemical surface, structural phase, grain size and fluctuations of the grain boundary of BTE films were analyzed and then their effects on the activation energy of the grain growth of the BTE films were revealed. BTE thin films were deposited on Si(100) substrates by electron beam physical vapor deposition (EB-PVD). XRD pattern analysis of the BTE films revealed a tetragonal crystal structure. Williamson–Hall analysis was used to confirm the tensile strain of the BTE thin films. The experimental results indicate that the Er doping in BaTiO3 show strong response by increasing the activation energy of the grain growth and increasing the grain size of the BTE films, while fluctuations of the surface roughness of the BTE films from 0.47 nm to 24.80 nm were also observed. Thin films: BTE2, BTE3, and BTE6 exhibit a grain growth exponent (n) of 5.71, 6.50, and 8.22 that respectively suggest a surface diffusion-controlled grain growth in these films. The activation energies for the grain growth came about 6.63, 6.95 and 19.7 kJ/mol for BTE2, BTE3 and BTE6, respectively, which were close to the values reported for the activation energy in BaTiO3. This was consistent with the high grain boundary density of the BTE films, which was responsible for the mechanism of surface diffusion and point defects. This behavior has been observed in case of BaTiO3, but for Erbium-doped barium titanate it has never been reported.

Novel zinc alumina bismuth borate glass system was fabricated according to the empirical formula x(ZnO)–5(Al2O3)–30(BiO3)–65-x(B2O3) with x = 0, 5, 10, 15, 20, 25 and 30 mol% using conventional glass melt-quenching technique. The structural, elastic and shielding properties of the ZnO–Al2O3–BiO3–B2O3 glasses were examined by X-ray diffraction (XRD), density, molar volume, ultrasonic velocities, and EPICS2017 simulation. The glass structure's amorphous phase was confirmed by XRD measurement. From the density measurement, the addition of ZnO will increase the density from 4.275 to 5.018 g/cm3 and the molar volume decreased from 44.479 to 38.595 cm3/mol. In addition, the OPD is decreased from 67.45 to 62.19 mol/cm3. The elastic properties approximated from measured shear (VS) and longitudinal (VL) ultrasonic velocities indicated that the decrease of B2O3 in glass network cause the rigidity of glasses increased from 2300 to 2621 m/s and 4082–4540 m/s when the ZnO content increased. Meanwhile, the longitudinal (L), shear (G), bulk (K) and Young's (E) modulus increased from 71.23 to 103.43 GPa, 22.61–34.47 GPa, 41.08–57.47 GPa and 57.29 and 86.18 GPa. Besides, Poisson's ratio decreased from 0.267 to 0.250 and micro hardness increased from 3.51 to 5.75 GPa. The EPICS2017 simulation program is used to determine the radiation shielding of the glasses. The results show a very interesting results where the replacement of B2O3 by ZnO causes an improvement of the attenuation competence for the glasses.

In the recent past, significant research effort has been dedicated to examining the usage of nanomaterials hybridized with lignocellulosic fibers as reinforcement in the fabrication of polymer nanocomposites. The introduction of nanoparticles like montmorillonite (MMT) nanoclay was found to increase the strength, modulus of elasticity and stiffness of composites and provide thermal stability. The resulting composite materials has figured prominently in research and development efforts devoted to nanocomposites and are often used as strengthening agents, especially for structural applications. The distinct properties of MMT, namely its hydrophilicity, as well as high strength, high aspect ratio and high modulus, aids in the dispersion of this inorganic crystalline layer in water-soluble polymers. The ability of MMT nanoclay to intercalate into the interlayer space of monomers and polymers is used, followed by the exfoliation of filler particles into monolayers of nanoscale particles. The present review article intends to provide a general overview of the features of the structure, chemical composition, and properties of MMT nanoclay and lignocellulosic fibers. Some of the techniques used for obtaining polymer nanocomposites based on lignocellulosic fibers and MMT nanoclay are described: (i) conventional, (ii) intercalation, (iii) melt intercalation, and (iv) in situ polymerization methods. This review also comprehensively discusses the mechanical, thermal, and flame retardancy properties of MMT-based polymer nanocomposites. The valuable properties of MMT nanoclay and lignocellulose fibers allow us to expand the possibilities of using polymer nanocomposites in various advanced industrial applications.

The extraction of CaO from waste eggshell can be used to produce new product known as calcium borate glass doped manganese (IV) oxide. A tertiary (B2O3)0.6 [(CaO)0.4]1-x (MnO2)x glass system with 0.010 ≥ x ≥ 0 M fraction were prepared using conventional melt-quenching technique. XRF spectroscopy confirms CaO as the main constituent in the calcined eggshell. XRD spectra unveils the two amorphous humps of the glass samples. FTIR analysis reveals the typical features of CaCO3 and B2O3 network. The density has opposite behaviour with molar volume as MnO2 content increases. Next, the optical band gap and refractive index are evidencing the formation of non-bridging oxygen in the glass matrix. The present glass system also has low polarizability, acidic in nature and have tendency to metallizing. The elastic properties of glass samples were determined using the ultrasonic technique. Elastic moduli such as longitudinal modulus, shear modulus, Young's modulus, bulk modulus, Poisson's ratio and hardness of the glass system were discussed.

Six glass samples composes the (70-y) B2O3-15TeO2-10Na2O-5PbO-yEu2O3, where y = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5 mol%, have been synthesized by conventional melt quenching technique. The properties such as the structural, thermal and spectroscopic properties were studied by employing the suitable characterizations tools, such as X-ray diffraction, differential scanning calorimetry, Raman spectroscopy, fourier transform infrared spectroscopy, magic angle spinning nuclear resonance spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The XRD, SEM and EDS confirm non-crystalline nature, microstructural and homogeneous, absence of impurity of glass samples, respectively. The DSC data reveals the good thermal stability of glasses. The FT-IR and Raman studies reveal the contribution of boron and tellurium in the network of prepared glasses, the presence of BO3, and BO4, a small amount of six-member boroxol rings, TeO3 and TeO4 structural groups. The MAS-NMR studies reveal the presence of quadrupolar interaction of BO4 and quadrupolar broadening of BO3 in all glasses and it also discloses the fact that only a small amount of BO4 is converted into BO3 during structural evolution.

Zinc oxide (ZnO) nanostructures were synthesized in the form of nanoparticles, nanoflowers and nanourchins. Structural, electronic and optical characterization of the samples was performed via standard techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence, Raman and ultraviolet-visible (UV-Vis) spectroscopy. Point defect structures which are specific to each morphology have been investigated in terms of their concentration and location via state-of-the-art electron paramagnetic resonance (EPR) spectroscopy. According to the core-shell model, all the samples revealed core defects; however, the defects on the surface are smeared out. Finally, all three morphologies have been tested as electrode materials in a real supercapacitor device and the performance of the device, in particular, the specific capacitance and the storage mechanism, has been mediated by the point defects. Morphology-dependent defective ZnO electrodes enable the monitoring of the working principle of the supercapacitor device ranging from electric double-layer capacitors (EDLC) to pseudo-supercapacitors. © 2020 The Royal Society of Chemistry.

Natural fibers are used as reinforcing materials in polymer composites due to some advantages such as renewable, low cost, environmentally friendly nature, and “good” strength and stiffness properties. Tensile, flexural, and impact testing are the typical major testing performed on natural fiber composites. In this presentation, sugar palm (Arenga pinnata [Wurmb] Merr.) fibers sized from macro- to nanometers, and their reinforcements with various polymer composites were reviewed. The matrix used was thermoplastic sugar palm starch (SPS) biopolymer. The incorporation of sugar palm fibers (SPFs) was due to the starch itself, which is poor in terms of processability and dimensional stability as well as weak mechanical properties in the final products. Therefore, improvement of these properties are done by incorporating these natural fibers as reinforcement. Considering the sustainability and environmental aspects, sugar palm tree-based biopolymer and natural fibers that are 100% renewable and biodegradable were fabricated. Overall, the reinforcement of plasticized SPS with SPF had enhanced the mechanical properties of the resultant composites. In addition, sugar palm-derived cellulose (SPC) composites were also prepared and used as reinforcing material for the improvement of the mechanical properties of SPS-based films. Further, bionanocomposites films were also prepared by collaborating SPS and sorbitol/glycerol with different nanofiber sugar palm nanocrystalline cellulose and nanofibrillated cellulose with compositions of 0–1.0 wt% using solution casting method. SPS nanocomposite films revealed increment in Young's modulus and tensile strength and with increasing nanofillers concentration from 0 to 1.0 wt%, respectively.

Currently, the harmful gas emission, rapid climate change, air and water pollution, and deterioration of earth's land surface are mainly produced by the aggressive utilization of petroleum-based plastic and the unmanaged garbage disposal including dumping and burning of polymeric products and substances. Many experts from throughout the globe revealed that the dumping of petroleum-based plastic and undecomposed materials is the main principle problem of environmental pollution. Hence, in order to overcome these challenging issues, biopolymers, such as starch, cellulosic-based polymer, and other biodegradable materials, are considered the most promising materials and as alternatives to non-biodegradable petroleum-based materials. This is due to their long shelf life properties such as resistance to enzymatic or chemical reaction and as they are biodegradable in nature. Starch is an abundantly available, highly biodegradable, cheap, and renewable biopolymer. However, some studies have found that the properties of starch biopolymer such as mechanical and water barrier are comparatively low than petroleum-based plastic. Therefore, nanofillers such as nanocellulose are introduced in order to overcome this issue. Nanocellulose has attracted huge attention due to its good physical and mechanical behaviors. In recent years, nanocellulose has also attracted the interest among researchers, since the technology capable to cater the environmental issues. This chapter explains the outline of current development in this particular field, including the isolation, characterization, behaviors, and various applications of nanocellulose reinforced starch biopolymer nanocomposites. Followed by explaining the distinctive properties of nanocellulose and its numerous preparation methods, an arranged introduction of various sources of nanocellulose reinforced biodegradable starch polymers is provided. Herein, nanocellulose reinforced starch biopolymer for engineering and interdisciplinary applications, comprising approaches for the transformation of various sources of cellulose to nanocellulose, and the technique of fabrication for their composites have been studied. Furthermore, the results of nanocellulose on the behavior of starch biopolymers are presented. Finally, the chapter summarizes with a new finding and innovation researches on nanocellulose reinforced starch biopolymer composites. In certain circumstances, an evaluation study was conducted between cellulose nanofiber and cellulose nanocrystals reinforced starch biodegradable polymers. Considering the vast amount of research on nanocellulose reinforced starch biopolymer composites, special highlights on such composites are allowed at the end of the review.

The use of polylactic acid (PLA) and polyhydroxyalkanoates (PHA) polymers in various advanced applications have been certified long time ago due to their promising properties. Processing methods of biodegradable thermoplastic polymer are similar to conventional thermoplastics but required adjustment on processing parameters or incorporations of compatibilizers. The differences in term of viscosity, melt flow rate, and melt strength have caused the existing processing parameters unsuitable for biopolymers. Thermal degradation is the normal issue needed to deal with, during biopolymer processing. Several important process methods, such as extrusion, injection molding, blowing molding, thermoforming, and 3D printing, have been discussed in this chapter for PHA and PLA biopolymers. Besides this, the developmental application of the biopolymers, especially in medical sector, has been reviewed in the last section of this chapter.

This work reports a one-pot chemical bath deposition (CBD) method for the preparation of selectively grown, morphology-tunable zinc oxide (ZnO) nanostructures provided via straightforward nanosecond fiber laser ablation. Nanosecond fiber laser ablation is different from lithographic methods due to its simple, time saving, and efficient film scribing abilities. Here, multiple morphologies of the ZnO nanostructures on the same substrate have been grown via laser ablation of the ZnO seeding layer. Selective and controlled ablation of the titanium layer, ZnO growth inhibitor, resulted in systematic growth of nanorod arrays, while the application of extensive fluence energies resulted in the penetration of the laser beam until the glass substrate induced the nanoflake growth within the same CBD environment. The laser penetration depth has been numerically investigated via COMSOL Multiphysics heat module simulations, and the optical variations between two nanostructures (nanorod and nanoflake) have been examined via Lumerical FDTD. The simultaneous growth of two morphologies served as an efficient tool for the enhancement of photoluminescence intensities. It increased the average charge carrier lifetimes of the thin films from approximately 2.01 to 9.07 ns under the same excitation wavelengths. The amplification in PL performances has been accomplished via the capstone of all-inorganic halide perovskite (IHP) deposition that brought a successful conclusion to lifetime responses, which have been increased by 1.4-fold. The development of IHP sensitized nanoscaled multimorphological ZnO thin films can, therefore, be used as potential nanomaterials for light-emitting-device applications.

The objectives of the present investigations are (1) to envisage a risk assessment plan for nonphospholipid-based topical ophthalmic emulsions with the help of failure mode and effect analysis (FMEA), (2) to screen the risky formulation and process variables by the Taguchi design, (3) to optimize systematically an emulsion formula by face-centered central composite design (CCD), (4) to incorporate cyclosporin A (0.05 or 0.1% w/w) into the optimized emulsions and predict the in vitro drug release kinetic via a particle diffusion-controlled mathematical model equation, and (5) to assess the emulsion's toxicity using in vitro hemolysis study. Through the risk priority number (RPN) scores of FMEA, half-normal and Pareto charts of the Taguchi design, 3D-response surface graphs, and overlay plots of CCD, the emulsion formula was systematically optimized. Irrespective of the two different drug loadings into optimized emulsions, the drug entrapment efficiency values ranged from 73.20 ± 0.13 to 74.42 ± 0.15%. The film diffusion or ion-exchange process fails to interpret the in vitro drug release kinetic profile. A permissible percentage hemolysis value of above 10% but below 25% guidance was observed for emulsions with or without cyclosporin A. The systematically optimized phospholipidless ophthalmic emulsions could further be exploited commercially for managing dry-eye syndrome.

A glass series of zinc tellurite was doped with erbium oxide and was successfully synthesized by employing a melt-quenching method. The glasses were prepared based on the chemical composition, [(TeO2)0.7 (ZnO) 0.3]1-x (Er2O3) x provided with different concentration of dopants, 0.01–0.05 M fraction. The structural and elastic properties of the samples were elucidated using equipment such as Fourier transform infrared (FTIR) and Ultrasonic equipment. By studying FTIR spectra, the presence of TeO4 at 601-623 cm−1 and non-existence of TeO3, ZnO and Er2O3 implies that these bonds have been altered. However, by implementing the deconvolution technique using Origin 6.0 software, the remaining functional groups have been found. Besides that, the elastic moduli and other elastic parameters of the glasses are generally found to vary with the increase of erbium oxide while the Poisson's ratio lies in the expected range of 0.2–0.3. A comparison is made between the respective elastic experimental and theoretical from 20.0 to 70.0 GPa which includes Makishima and Mackenzie, rocherulle, ring deformation and bond compression models. The outcome highlights that rocherulle model match well with the experimental elastic results using coefficient of determination, R2.

This paper presents a linear low-dropout (LDO) voltage regulator in 0.18-pm CMOS technology. The proposed LDO consists of voltage reference, error amplifier, pass device, output capacitor and resistive feedback network. A symmetrical operational transconductance amplifier (OTA) is implemented as an error amplifier and a PMOS transistor is used as a pass device to produce low dropout voltage and low quiescent current. The proposed design is simulated using Spectre simulator in Cadence software to verify its performances. The simulation results indicated that the LDO regulator achieves a regulated output voltage of 1.5 V with the ranges of supply voltage from 1.7 V to 2.0 V. The LDO regulator has a dropout voltage of 19.3 mV under maximum load current of 1.1 mA. The proposed LDO regulator is suitable for power management system.

Nowadays, active search for more efficient and improved glass material to be employed as laser host has been take place in order to have laser with enhanced performance. In this research, erbium oxide doped rice husk biosilicate zinc borotellurite glasses have been fabricated successfully via conventional melt quenching technique. XRD pattern reveals that the prepared glasses are amorphous in nature while FTIR spectra records the presence of Si-O-Si, TeO3, BO4 as well as BO3 vibrational groups in the fabricated glasses. Increasing density from 3.3505 g/cm3 to 4.1852 g/cm3 along with the rigidity of the glass as hinted in the values for elastic moduli from 55.0 GPa to 250.0 GPa is caused by the incorporation of erbium oxide that reduce the amount of non-bridging oxygen in the glass matrix. Three bands that are recorded in PL spectra correspond to the violet, blue and green emission.

Fiber is one of the famous waste material in this country and fibre also can be used in order to increase the mechanical properties of concrete. Mechanical properties of concrete will be testing such compression strength and splitting tensile strength. Concrete has low tensile strength due to the brittleness properties. The coconut coir fibre processed by using the fabricated. Then the coconut coir fibre will be a sink in sodium hydroxide for 1 week and in pure water for 2 weeks at room temperature. The authorities that are already going through under treatment gave coconut coir fibre and it had been cut into a size of 25mm to 30mm. Three different ratios used in this research, which is 3%, 4% and 5% of coconut coir fibre as an additive to the concrete. There will be two types of specimens, which are cube size of 100mm x 100mm and cylinder 100mm diameter with 200mm length. All the samples cured in a water tank for 7 and 28days. The rate that had been using for this compression strength and splitting tensile strength follow the British Standard (BS 1881-116:1983). This research outcome is the addition of coconut coir fibre with concrete to increase the compression strength of the cube sample but it has lower strength than normal concrete. Meanwhile, for the splitting tensile strength of this reinforced concrete with coconut coir fibre as an additive has higher strength than normal concrete. The result proved that the addition of fibre will increase the mechanical properties of concrete but at the same time, it will decrease the workability of concrete.

Laser micromachining provide significant effect in thin film solar industrial field especially in determining cell efficiency of each panels. However, there is an issue in determining scribing failure or defect on solar module. This research aims to investigate the defects of laser micromachining process in thin film solar module in manufacturing fields. Machine vision inspection system is used as inspection tools and to investigate the defect of laser micromachining in thin film solar cells. As a result, two major defects is define which is scribe line quality and scribe line position defects in every scribe line. By identifying the defect cause by laser micromachining through machine vision, quality control plan can be taken together to prevent reoccurrence.

Three-dimensional (3D) zinc oxide nanosheets (ZnO-NS), assembled on the FTO coated glass substrates after chemical treatment, have been achieved via a simple yet effective chemical bath deposition technique. The exploration of chalcogenide nanoparticle sensitization on ZnO-NS thin-film photoanodes led us to a spectacular enhancement in the photoelectrochemical conversion efficiency for solar-driven water splitting process as compared to the bare 3D-ZnO-NS. The maximum incident photon-to-charge carrier efficiency of bare 3D-ZnO-NS has been enhanced by approximately four folds as a result of cadmium sulfide (CdS) and cadmium selenide (CdSe) sensitization and the efficiency value have reached to 51% at 550 nm. Besides, the maximum charge injection and charge separation efficiencies of the ZnO eCdSe electrodes have been calculated as 93% and 64%, respectively. Numerical examination of the optical absorption and electrical field distribution has been performed via the finite-difference time-domain (FDTD) method in order to investigate the basis of the enhancement in the photoelectrochemical efficiencies of the 3D-ZnO-NS photoelectrodes. FDTD numerical simulation proved that the accumulation of rectangular 2D-nanosheets of ZnO in 3D-microspherical forms enhanced the light absorption significantly. Moreover, FDTD results also verified that the optical absorption of the ZnO electrodes has been extended from ultraviolet to visible region via CdS and CdSe nanoparticle deposition. (c) 2020 Elsevier B.V. All rights reserved.

Recently, the rapid growth in photonic field has increased the demand for nonlinear materials with higher performance and greater efficiency. Hence, a thorough investigation on the nonlinear optical properties of materials are essential and need to be done for possible future application of the material in photonic field as optical limiting or optical switching devices. Thus, through this research, the crucial parameters in nonlinear optical properties of zinc borotellurite glasses doped with lanthanum oxide and lanthanum nanoparticles were studied and investigated extensively. The two series of glasses were successfully fabricated via conventional melt-quenching technique. The fabricated samples were characterized by using Fourier Transform Infra-Red (FTIR) spectroscopy as well as Z-scan technique in order to study the structural and nonlinear optical properties of the glass systems. The existence of various amount of TeO4, TeO3, BO4 and BO3 in all the prepared glasses are proven through the observable absorption bands in the FTIR spectra. Inconsistent trends recorded for both nonlinear absorption coefficient and nonlinear refractive index might be associated with the simultaneous creation of bridging as well as nonbridging oxygen which eventually affect the values for both parameters. The figure of merit of the prepared glasses with values ranging from 0.055 to 0.267 which are smaller than one hints that the glass materials possess potential to be employed as all optical devices. 0.03 M fraction of lanthanum nanoparticles doped zinc borotellurite with FOM value larger than 1 has proven the ability of the respective glass to be employed as efficient all optical switching devices. The determined nonlinear optical parameters of the glasses should be able to provide sufficient and useful information on the fabricated glass samples for future application in photonic field.

In this report, the growth of zinc oxide (ZnO) nanocrystals with various morphologies, nanoflower, nanosheet, and nanorod, on flexible stainless steel (SS) foils to be utilized as photoanodes in photoelectrochemical (PEC) solar cells has been presented. It has been aimed to provide flexibility and adaptability for the next generation systems with the incorporation of SS foils as electrode into PEC cells. Therefore, physical deformation tests have been applied to the prepared ZnO thin film photoanodes. These thin films have been thoroughly characterized before and after straining for better understanding the relationship between the morphology, straining effect and photoelectrochemical efficiency. We observed a notable increase in the maximum incident photon-to-current efficiency (IPCE) and durability of all ZnO photoelectrodes after straining process. The increase in IPCE values by 1.5 and 2.5 folds at 370 nm has been observed for nanoflower and nanorod morphologies, respectively after being strained. The maximum IPCE of 69% has been calculated for the ZnO nanorod structures after straining. Bending of the SS electrodes resulted in the more oriented nanorod arrays compared to its flat counterpart, which improved both the light absorption and also the photo-conversion efficiency drastically. The finite-difference time-domain simulations have also been carried out to examine the optical properties of flat and bent ZnO electrodes. Finally, it has been concluded that SS photoanodes bearing ZnO semiconducting material with nanoflower and nanorod morphologies are very promising candidates for the solar hydrogen generator systems in terms of efficiency, durability, flexibility, and lightness in weight.

Glasses with chemical composition {[(TeO₂)0.7 (B₂O₃)0.3]0.8 [SiO₂]0.2}1-x {Sm₂O₃ NPs}x where x = 0.01 to 0.05 molar fraction have been fabricated using conventional melt-quenching method. Fourier transform infrared (FTIR) spectra reveal the presence of TeO3, SiO2 and BO3 structural units in the glass network. The existence of samarium oxide nanoparticles was recorded through high resolution transmission electron microscopy (HR-TEM) with particle size of 71.74 nm. Meanwhile, the optical properties of fabricated samples were determined by UV–vis analysis. The variation in the optical band gap identifies the modification in the glass network to the formation of bridging oxygen (BO) and non-bridging oxygen (NBO). Other optical parameter including refractive index, Urbach energy, electronic polarizability, oxide ion polarizability and optical basicity were determined. The metallization criterion values obtained is in the range of 0.403 to 0.409, which suggest that the glass material has a huge potential applications, in non-linear optics fields.

Peat soil is one of the abundant soft soil material vastly found in east costal area of Peninsular Malaysia. Soft soil can be treated using wet and dry mixing method for the purpose of deep stabilization method. It is either mixed thoroughly with conventional or nonconventional binder. Among other properties of concern in soil, stabilization is a strength of treated peat medium which is much likely dependant on condition of wet and dry mixture between binder and treated soil. Essentially, nonconventional binder such as Melamine Urea Formaldehyde (MUF) polymer resin has recently found a fresh look in this study intendedly for future possible application, especially for rapid application stabilization technique. This chapter presents the performance of two types of MUF resin, namely MUF powdered (MUF-P) and MUF liquid (MUF-L) resin which were tested to treat peat soil for determination of unconfined compressive strength (UCS), and elasticity modulus. Both type of resins were mixed with peat specimens as wet and dry binder for stipulated periods of curing times (1–7 days). Results showed that MUF-P resin had performed significantly to improve UCS of initially high moisture content of treated peat soil specimens for up to 287 kPa in a week. Improvement of elasticity modulus, E50 in term of secant modulus also noticeable within 7–14 days of curing periods. However, MUF-L has significantly improved UCS of treated specimens particular for air curing application at lower range of moisture content with significant improvement of up to 500 kPa within 7 days curing period.

Novel nanoporous catalysts from selective dissolution of alloys have been prepared for fast hydrogen generation from chemical hydrides. Pt and Ru have been used as precious metals in the alloys, while the nonprecious metal is Al. The alloy composition has been arranged by sputtering power of Al, which is varied from 200 to 400 W for Pt-Al and Ru-Al alloys. The influence of particle size on the sputtering power of Al has been demonstrated. The particle size of the Pt nanoparticle decreases from 900 to 90 nm when the sputtering power of Al is increased from 200 to 400W. However, the particle size of the Ru nanoparticle decreased from 610 to 55 with the same increase in Al sputtering power. The hydrolysis reaction rate of NaBH4 scales with the sputtering power of Al and has been raised from 20 to 90 L min(-1)g(catalyst)(-1) for Pt while it increases from 23 to 110 L min(-1) g(catalyst)(-1) for Ru. The BET analysis has demonstrated that the measured surface areas of the Pt and Ru nanoparticles are approximately 55.5 and 151 m(2) g(-1), respectively. Joint like morphology providing the porous structure has been clearly concluded by TEM analysis. The average pore sizes are 1 and 10 nm for the Ru and Pt nanoparticles, respectively. In this study, fast hydrogen generation with lower activation energies of 31.7 and 32.1 kJ mol(-1) has been achieved for the Pt and Ru nanoparticles, respectively. The critical parameters demonstrating the high catalytic activity in the hydrolysis reaction of NaBH4 are reported for the catalysts developed by the dealloying process. (c) 2018 Elsevier B.V. All rights reserved.

Keyword : Keyword: Speed of penetrations, CPT, Mackintosh probe, rate effect, shear strength Abstract. A wide range of industrial applications, on land and offshore, require the solution of time domain problems and an associated understanding of rate effects in clay soils. In recent decades many researchers have examined the correlation between shear strength of soils and variation of shear strain rate and it is generally accepted that the strength increases by 1-5% for each order of magnitude increase in shear strain rate. This paper discusses the effects of penetration rate on the penetration resistance (qc) by using cone penetration test (CPT) test setup. The research had been conducted at RECESS and cone penetration test were used in three selected range of rate which were 0.5 cm/s, 1cm/s and 5cm/s. In addition, Mackintosh probe test had been considered as comparison with CPT test for the unconfined compressive strength. The result shows different penetration rate influenced the soil shear strength. For the slowest rate (0.5 cm/s), the shear strength was approximately 0.15% less compared to the standard rate (2 cm/s). However, for the highest rate (5 cm/s), the shear strength was 0.22% more than the reference rate (0.5 cm/s). In conclusion, it is suggested that the RECESS clay soil influenced by the rate effect and in agreement with previous research findings.

Langmuir-Blodgett technique was applied to build optically homogeneous film of functionalized multi-walled carbon nanotubes (MWCNTs) on paper substrate. The palladium (Pd) nanoparticles were drop-casted onto MWCNTs network films before being exposed in hydrogen (H2) gas molecules environment under vacuum and atmospheric pressure at room temperature. The results demonstrate that the functionalized MWCNTs dispersed with Pd nanoparticles show good H2sensing response on paper substrate where the sensitivity of around 10 % was recorded at only 2 minutes exposure time.