Search

Predictive maintenance, facilitated by smart devices and cyber infrastructure, is used for essential equipment like power transformers, enhancing power grid stability and reducing operating costs. As part of predictive maintenance, machine learning (ML) methods are employed to predict the remaining useful life (RUL) of power transformers, which can be vulnerable to cyber-attacks, especially data contamination attacks. Hence, this work introduces false data injection (FDI) attacks in ML-based RUL prediction and investigates the impacts on lifetime prediction. Three different attack templates of FDI attacks are implemented to corrupt the input data of extreme gradient boosting (XGBoost), extra trees (ETs) and random forest (RF)-based lifetime predictor models, where single attack templates are found severe compared to a mixed attack template of FDI attacks. Also, adversarial training is presented as a countermeasure, where the adversarially trained XGBoost model outperforms the other two models under normal conditions and cyber-attacks. Experiment results indicate that the lifetime prediction errors of the proposed model in all scenarios can be maintained at about 6 and 3 in terms of RMSE and MAE, respectively. • Introducing cyber-attacks on ML-based power transformer lifetime predictors. • Investigating the severity of single and mixed models of FDI attacks on predictors. • Presenting a comparative analysis of predictors under normal cases and cyber-attacks. • Proposing an adversarial training-based countermeasure to mitigate the severity. [ABSTRACT FROM AUTHOR]

• Exploring PLS in energy research, revealing applications and addressing challenges. • Tackling limitations in PLS implementation, considering confounding variables, sample sizes, and integration. • Beyond replication issues, focusing on reliability, multi-physics phenomena, and optimized designs. • Balancing thermal, fluid, and electrical factors, enhancing PLS performance across energy applications. • Innovative fabrication techniques, scaling up PLS production for efficient, cost-effective energy solutions. Lattice structures, with their exceptional characteristics such as high specific strength and stiffness, thermal insulation, and biocompatibility, find a wide range of applications including bio-medical, thermal, automobile and aerospace industry. This study explores their potential for energy research, provides an overview of Periodic lattice structure (PLS) design and fabrication, and classifies them based on their energy function. It aims to provide insights into the potential applications, advancements, challenges, and future directions related to PLS implementation in energy research. The study categorized the recent advances and challenges of using PLS in energy conversion, storage, and transport applications and examines the challenges and limitations associated with them. The challenges and limitations include problems related to study design, reproducibility, sample sizes, multi-physics phenomena, integration with other energy storage components, interdisciplinary research, manufacturing accuracy, durability, scalability, and economic feasibility. Future research directions are suggested to address these challenges and opportunities, such as evaluating PLS performance on a broader scale, developing accurate modeling techniques, investigating underlying mechanisms, utilizing multi-physics modeling tools, examining long-term performance, exploring practical applications, and exploring alternative fabrication methods. [ABSTRACT FROM AUTHOR]

Machine learning provides a probabilistic framework for metabolic pathway inference from genomic sequence information at different levels of complexity and completion. However, several challenges, including pathway features engineering, multiple mapping of enzymatic reactions, and emergent or distributed metabolism within populations or communities of cells, can limit prediction performance. In this article, we present triUMPF (triple non-negative matrix factorization [NMF] with community detection for metabolic pathway inference), which combines three stages of NMF to capture myriad relationships between enzymes and pathways within a graph network. This is followed by community detection to extract a higher-order structure based on the clustering of vertices that share similar statistical properties. We evaluated triUMPF performance by using experimental datasets manifesting diverse multi-label properties, including Tier 1 genomes from the BioCyc collection of organismal Pathway/Genome Databases and low complexity microbial communities. Resulting performance metrics equaled or exceeded other prediction methods on organismal genomes with improved precision on multi-organismal datasets. [ABSTRACT FROM AUTHOR]

In this study, a novel technique is applied to recover the pyrolysis products (bio-oil, char, and non-condensable gas) from algal biomass (E. compressa) by utilizing solar energy. To observe the parametric effect on product distribution, the temperature was varied from 250 to 600 °C, heating rate of 20–100 °C/min, particles feed size of <0.5–2.5 mm and sweeping gas flow rate of 3–15 liter per minute (lpm). The maximum solar bio-oil yield of 38.12 wt% was obtained at 400 °C, 9 lpm, <0.5 mm and 20 °C/min. The non-condensable gas evolution rate increase with a rise in temperature except for CO 2. The bio-oils were characterized and their economic feasibility was evaluated by proximate, ultimate and GC-MS analysis whereas char product was characterized by proximate and FTIR. The gaseous products were analyzed by micro-gas chromatography (GC). The products yield and their characteristics highly dependent on temperature variation. The products possess high energy contents which are a potential alternative fuel. The energy upgrading factor, and solar to chemical conversion efficiency was also calculated. Operating range: 300-600 °C, 20-100 °C/min, < 0.5–2.5 mm and 3–15 lpm. Image 1 • Utilization of solar energy in pyrolysis of algal biomass is a novel technique. • Temperature has a drastical effect on product distribution. • A maximum bio-oil yield of 38.12 wt% at 400 °C, 9 lpm, < 0.5 mm and 20 °C/min. • Products (bio-oil, char and no-condensable gas) calorific value successfully upgraded. • Products characteristics were within ASTM and potential for alternative fuel. [ABSTRACT FROM AUTHOR]

Global processes of urban growth lead to severe environmental impacts such as temperature increase with an intensification of the urban heat island effect, and hydrological changes with far reaching consequences for plant growth and human health and well-being. Urban trees can help to mitigate the negative effects of climate change by providing ecosystem services such as carbon storage, shading, cooling by transpiration or reduction of rainwater runoff. The extent of each ecosystem service is closely linked with the tree species as well as with a tree's age, size, structure and vitality. To evaluate the ecosystem services of urban trees, the process-based growth model CityTree was developed which is able to estimate not only tree growth but also the species-specific ecosystem services including carbon storage, transpiration and runoff, shading, and cooling by transpiration. The model was parametrized for the species small-leaved lime (Tilia cordata), robinia (Robinia pseudoacacia), plane (Platanus × acerifolia) and horse chestnut (Aesculus hippocastanum). The model validation for tree growth (stem diameter increment, coefficient of correlation = 0.76) as well as for the water balance (transpiration, coefficient of correlation = 0.92) seems plausible and realistic. Tree growth and ecosystem services were simulated and analyzed for Central European cities both under current climate conditions and for the future climate scenarios. The simulations revealed that urban trees can significantly improve the urban climate and mitigate climate change effects. The quantity of the improvements depends on tree species and tree size as well as on the specific site conditions. Such simulation scenarios can be a proper basis for planning options to mitigate urban climate changes in individual cities. Unlabelled Image • Climate change and increasing urbanization will clearly affect the urban climate. • Ecosystem services of urban trees can mitigate urban climate changes. • An urban tree growth model is introduced which is able to simulate these services. • Growth is calculated process based in dependence on environmental conditions. • Ecosystem services strongly depend on species, tree age and tree size. [ABSTRACT FROM AUTHOR]

Abstract Summer mortality of some bivalve species is often associated with the change of environmental temperature. This study compares the response of immunological parameters to temperature change in three marine bivalves: Pacific oyster Crassostrea gigas , Mediterranean mussel Mytilus galloprovincialis and mud cockle Katelysia rhytiphora. Each species was exposed to three temperatures, 15 °C, 20 °C and 25 °C for 14 days. The total haemocyte count (THC), phagocytosis, reactive oxygen species (ROS) and the activity of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) were used as indicators to measure the response of each species to different temperatures. The highest temperature (25 °C) significantly increased the THC and phagocysis of haemocytes in all species. The SOD and CAT activities in the haemocytes of M. galloprovincialis and K. rhytiphora rapidly increased with temperature elevation, concomitantly with the increase of ROS ions. In contrast, the increases of ROS and SOD in C. gigas only occurred from 20 °C to 25 °C, suggesting that this intertidal species is more adaptive to different temperature levels. This study indicates that the activities of antioxidant enzymes can reflect the immune response of marine bivalves to thermal stress. Intertidal species such as Pacific oysters have a greater tolerance to thermal stress than subtidal species (e.g. Mediterranean mussel) and demersal species buried in sand (e.g. cockle). Highlights • Antioxidant enzymes in the haemocytes reflect a response of bivalves to thermal stress. • Thermal stress increases haemocyte number and phagocytic activity. • Intertidal species tolerate more thermal stress than subtidal or buried demersal species. [ABSTRACT FROM AUTHOR]

The main objective of this investigation is to compare catalytic activity of three different catalysts derived from chicken waste. The prepared catalysts were characterized by DTG, SEM, BET, XRD, and FT-IR. The effect of catalysts (chicken manure, chicken bone, and egg shell) on biodiesel yield (from E. compressa algal oil) were evaluated by varying calcination temperature, reaction temperature, molar ratio, catalyst amount, mixing speed, reaction time, and water content in methanol. The maximum biodiesel yield was obtained for egg shell catalyst-95% while for chicken bone catalyst −94% and chicken manure catalyst −85% at 9:1 M, 5% (w/w) of catalyst amount, 65 °C, 2% water content, and 400 rpm for 3 h. The chicken bone catalyst is highly active in reaction but in presence of water content (max. 2%) in methanol egg shell shows higher biodiesel yield performance. The recovered catalyst can be used maximum three times with a slight deviation. The quality of biodiesel merged with standards value. The conversion of waste raw materials into valuable resources make this method a cost-effective and reveals a recyclable procedure for the production of biodiesel. [ABSTRACT FROM AUTHOR]

Highlights • Water hyacinth biomass was used as a potential novel feedstock. • The max. yield of bio-oil 44.9 wt%, at 350 °C, 30 °C/min and <0.5 mm at 6 lpm. • Products yield strongly influenced by temperature. • Syngas evolutionary behavior was analyzed. • Bio oil and char can be used as a low-grade fuel/chemicals. Abstract In this investigation, the effect of operating parameters on product distribution for the conversion of water hyacinth into most valuable product bio oil as well as char and gases are investigated. To observe the parametric effect on product distribution, the temperature was varied 300–600 °C, heating rate 10–50 °C/min, particle size of the feed <0.5–2.5 mm and carrier gas nitrogen flow rate 0–12 lpm. The highest bio-oil yield of 44.9 wt% was obtained at 350 °C, 30 °C/min, particle feed size less than 0.5 mm and 6 lpm. The results show that the product yield is strongly influenced by the temperature variation whereas weakly affected by the heating rate. The biomass and the products were characterized by ultimate, proximate, DTG, FTIR, 1H NMR, and GC–MS. Syngas evolution increase with the increase of temperature except CO 2. The quality of bio-oil is perspective as a source of value-added chemicals and char is a promising source for the production of carbonaceous materials as well as solid fuel. [ABSTRACT FROM AUTHOR]

Environmental stresses are increasing over time adversely affecting crop productivity. To face these stresses, plants adopt endogenous mechanisms, but they are not enough in most cases. Therefore, the effect of exogenous application of proline, silicon (Si) or methionine on growth and yield criteria, leaf physio-biochemical properties and leaf anatomical structure of cowpea plants grown under three levels of water deficit (W 0 ; 60, W 1 ; 40 and W 2 ; 20% of soil water holding capacity) was investigated. The water level W 0 was adequate to optimum cowpea plant growth and specified as a control. Results obtained indicated that growth criteria (i.e., shoot dry weight, plant height, leaf area and number of branches per plant), yield characteristics (i.e., dry seed weight and biological yield per plant, and 100-seed weight), contents of leaf chlorophylls a and b , total carotenoids, shoot and seed nutrients (i.e., N, P and K), and leaf relative water content and membrane stability index were significantly decreased, while activity of leaf antioxidant enzymes such as peroxidase (POX), superoxide dismutase (SOD) and catalase (CAT), content of leaf proline and electrolyte leakage, and shoot Si were significantly increased under water deficit stress (W 1 and W 2 ) conditions compared to the control (W 0 ). However under water deficit stress, foliar application of proline, Si or methionine seemed to overcome the harmful effects of water deficit stress, at varying degrees, on the abovementioned cowpea plants characters, which were improved, compared to the corresponding controls. The Si was the most helpful one, where it increased growth criteria (i.e., shoot dry weight, plant height, leaf area and number of branches per plant), yield characteristics (i.e., dry seed weight and biological yield per plant, and 100-seed weight), contents of leaf chlorophylls a and b , total carotenoids, shoot and seed nutrients (i.e., N, P and K), and leaf relative water content and membrane stability index, and further increased shoot Si content and leaf antioxidant enzyme activities of cowpea plants compared to those of either proline or methionine application. For leaf anatomical features, the width of midvein and xylem, and the thickness of midvein, phloem and xylem tissues, and palisade and spongy tissues of leaf blade were decreased with increasing the water deficit stress; however, foliar spray of Si improved all histological features compared to those of untreated plants. [ABSTRACT FROM AUTHOR]

Deposition of Ni via autocatalytic (electroless) plating inevitably contains a specific amount of P (usually 6–10 wt.%) due to the use of hypophosphite reducing agent in the autocatalytic reaction. The focus of this study is to investigate the effect of P content on the solderability between pure Sn and a Au/Ni– x P/Cu pad, where x was 6 wt.% (10.8 at.%), 8 wt.% (14.1 at.%), and 10 wt.% (17.4 at.%). We found that the intermetallic compound (IMC) species formed at the interface between solder and Ni– x P and the Ni– x P pad's depletion both strongly depended on x . The P-dependent Ni– x P depletion was ascribed to various IMC formations. The dependence of the IMC species on the P content can be rationalized using a Ni–P–Sn isotherm. Additionally, high-speed ball shear test showed that the difference in the interfacial microstructures arising from various x values might significantly affect the mechanical properties of solder joints. These findings revealed that the P content in the Ni–P platings is a very important factor of solderability. [ABSTRACT FROM AUTHOR]

The ensemble Kalman filter is, due to its computational efficiency, becoming more and more popular as a method for estimating both model states and parameters in hydrologic modeling, also for nonlinear state propagation models. In the ensemble Kalman filter the calculation of the error correlations, and hence the filter update, is done based on the ensemble of model evaluations and can therefore be strongly influenced by a few ensemble members with extreme values. With nonlinear state propagation models, extreme values can be a common phenomenon that can be, especially if there are nonlinearities between the observed variable and the modeled states, problematic during the filter update. An illustrative example of this problem is shown using an unsaturated flow model where the modeled states are pressure heads and observations are water content. It is demonstrated that the ensemble Kalman filter can in this case yield a deterioration of state predictions. We discuss the normal score transform and the transform with the retention function applied to the model states in order to mitigate this problem. It is shown that both transforms improve the estimation of the model states and parameters. [ABSTRACT FROM AUTHOR]

Absolute partial and total electron ionization cross sections for uracil in the gas phase as a function of energy up to 500 eV are measured using the well-known relative flow technique (RFT). These measurements have significant consequences for the study of radiation damage, tests of several theoretical models and application of the RFT for molecules existing in solid form at room temperature. Also presented are the thresholds for the formation of various fragment ions from uracil and the comparison of total ionization cross section with the existing results. [ABSTRACT FROM AUTHOR]

No matter how vigilantly an experiment is performed, errors always there inside the experimental results. Since the results of laser based optical experiments are somewhat loftier in precision, commonly, sources of errors are mistreated. However, ample error scrutiny is vital in quantifying of physical parameters of liquids such as Soret and diffusion coefficients. There are two types of experimental errors, explicitly, systematic error and random error. Systematic error is associated to the apparatus and cannot be enhanced by recurrent experiments. Frequent systematic errors in Mach–Zehnder Interferometer (MZI) techniques originate from stability of laser wavelength, resolution of the electronics component etcetera. Random error is interrelated to the variation in the equivalent measurements of repeating experiment. Resolution of electronic components likewise constructs random errors by providing diverse values in the recurring experiment. Foremost, random error of MZI is caused by the environmental circumstances such as nonconformity of background light, air temperature, and air humidity. In this current amendment, a meticulous error analysis has been accomplished for evaluating thermodiffusion or Soret coefficients of hydrocarbon binary mixtures. Based on our knowledge, such a completed error scrutiny for measuring Soret coefficients using MZI does not yet exist in the literature. Study reveals that the utmost error of measuring Soret coefficient using MZI is less than 0.22%. [ABSTRACT FROM AUTHOR]

Abstract: BRAF is one of the most commonly mutated proto-oncogenes and plays a significant role in the development of numerous cancers of high clinical impact. Due to the commonality of BRAF mutations, a number of BRAF inhibitors have been developed as tools in the management of patients with cancers dependent on the action of mutant BRAF to drive cellular proliferation. In this review, we examine the current state of clinical trials and laboratory research concerning BRAF inhibitors in development and available for clinical use. We contrast the effectiveness of type-I and type-II BRAF inhibitors, the former typically showing much more restricted inhibitory selectivity and greater patient response rates. [Copyright &y& Elsevier]

Abstract: Ever since the discovery of the Soret effect, numerous experimental and theoretical works have been accomplished to understand the phenomena in terms of scientific interpretation. There is published review articles existed focusing in different aspects of Soret effect such as, experimental techniques, theoretical approaches, and combination of both theoretical and experimental approaches. However, most of the articles focused on recent or short era only. It is essential for the novice researchers to have historical or chronological database of the works already done by others. In the contemporary study, a historical database of experimental and theoretical works has been offered. Major challenges, limitations, and technical hitches of performing experiments on ground (earth) condition has been selected, and cautiously deliberated. Contemporary experimental works performed in microgravity environment have been incorporated. All of the experimental methodologies and theoretical models have been addressed briefly. However, because of its popularity remarkable attention has been focused on the experiments with optical techniques, and theoretical models based on non-equilibrium thermodynamics. [Copyright &y& Elsevier]

Abstract: B-Raf is one of the more commonly mutated proto-oncogenes implicated in the development of cancers. In this review, we consider the mechanisms and clinical impacts of B-Raf mutations in cancer and discuss the implications for the patient in melanoma, thyroid cancer and colorectal cancer, where B-Raf mutations are particularly common. [Copyright &y& Elsevier]

Highlights: [•] Measurement of thermodiffusion coefficient using interferometry. [•] Measurement of thermodiffusion coefficient using theoretical approach. [•] Digital Image processing. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tunable structural colors are realized using an Au/Si 3 N 4 /Al trilayer structure. • Arc plasma deposition (APD) is employed to control the morphology of the Au layer. • Bruggeman's EMA can be used for estimating the refractive indices of APD Au layers. • Changing the Au coverage and Si 3 N 4 layer thickness yields a wide range of colors. Structural colors have diverse applications in optical filters, surface decoration, photovoltaics, and digital displays. In this study, an arc plasma deposition (APD) method was employed for fabrication of the top Au layer in the asymmetric Fabry–Perot cavity structure of Au/Si 3 N 4 /Al. With an increasing number of APD pulses (n P), the morphology of the Au layer gradually changed from a dispersion of nanoparticles (NPs) to a nanoporous film and then to a dense film, which in turn led to a change in the refractive index of the Au layer. The structural colors of the Au/Si 3 N 4 /Al structure were mainly governed by the interference effect. The optical constants of the NP-dispersed and nanoporous Au layers could be reasonably estimated based on Bruggeman's effective medium approximation. When the Au layers deposited with different n P were combined with dielectric Si 3 N 4 layers of various thicknesses (h d), the full range of color hue with a wide range of color chroma could be realized using the Au/Si 3 N 4 /Al trilayer structure. The color hue was predominantly governed by h d , and the color chroma gradually increased with n P for a given value of h d. [ABSTRACT FROM AUTHOR]

Abstract: Refractive index is one of the most important physical properties of transparent solid, liquid and gas. Accurate knowledge of refractive index is highly relevant to correlate with concentration, temperature, wavelength and pressure in non-intrusive experiments carried in transparent fluids. It can be used for the identification and characterization of pure materials, for the measurement of concentration of multi-component mixtures etc. In this current scope, refractive indices of five binary mixtures decane (C10H22)–isobutylbenzene (IBB), decane (C10H22)–1,2,3,4tetrahydronaphthalene (THN), dodecane (C12H26)–isobutylbenzene (IBB), dodecane (C12H26)–1,2,3,4tetrahydronaphthalene (THN) and isobutylbenzene (IBB)–1,2,3,4tetrahydronaphthalene (THN) have been measured using both Mach–Zehnder interferometer and a multi-wavelength Abbemat refractometer. Temperature and concentration coefficient of refractive indices or so called contrast factors as well as their individual correlation to calculate refractive indices have been presented for wide range of visible spectrum i.e., 436nm to 657nm. Comparison with available literature data and mixing rules shows that new correlation can predict the experimental data with some acceptable error. [Copyright &y& Elsevier]

The present study is an attempt to describe the size frequency distribution, length weight relationships and fecundity estimates of long-spined Sea Urchin, Diadema setosum from the Pulau Pangkor, Peninsular Malaysia. In total 101 specimens of  D. setosum were collected from the inter-tidal reef of Pulau Pangkor of Parek during the breeding season in May–August, 2010. Individual total length (TL) was measured using digital slide calipers and individual body weight (BW) was taken using a digital balance. Mean length of D. setosum was estimated as 59.66 mm and the mean weight was 101.68 g. Among the 101 specimens, 52 were males and 49 were females, indicating a sex ratio of male to female of 1:0.94. The logarithmic form of length-weight relationship of D. setosum was Log W = −1.3977 + 1.9049*Log TL, while the exponential form of equation obtained for the length-weight relation was W = 0.04*TL1.9049. The value of regression co-efficient (r2) estimated for the species was 0.63. The mean fecundity was estimated at 7,313,600 (±567,992) with a range between 6,290,000 and 7,980,000 eggs. Analysis of the relationship between the absolute fecundity (F) and total length (TL), and also between the fecundity and drained body weight (DW), revealed a linear regression model with a positive and significant relationship. This study presents results on the total length-body weight relationships and fecundity estimates of this Sea Urchin from Pulau Pangkor, Peninsular Malaysia for the first time. [ABSTRACT FROM PUBLISHER]

Abstract: The effervescent atomization from an industrial Coker feed nozzle is compared for two different gas densities (air and mixed gas of 81.4vol.% helium/18.6vol.% nitrogen) at equivalent operating temperatures. The application is to observe the similarity of lab tests using air at 20°C to the industrial process using steam at 300–400°C. The effects of operating conditions, such as gas to liquid mass ratio, mixing pressure and void fraction on the flow regime, bubble size, and droplet size distribution were also examined in this study. The experiments were performed using mixtures of water with air or mixed gas, which resulted in gas to liquid mass ratios ranging from 1% to 4%. Stroboscopic back scattered imagery (SBSI) indicates that the average bubble size inside the nozzle conduit is similar when air and water are used as the process fluids, when compared to the case when mixed gas and water are used as the process fluids. Under similar conditions, the Phase Doppler Particle Anemometer (PDPA) data indicate that the droplet size in the spray is similar when using either mixed gas or air as the atomization gas. Experimental results obtained by high-speed video shadowgraphy (HSVS) indicate that the flow pattern inside the nozzle feeding conduit was slug flow with a tendency to attain annular flow with increased air to liquid mass ratios. Thus, from the experimental results it is evident that the smaller molecular weight of the mixed gas versus air (8.4 versus 29) does not significantly reduce the bubble (<±10% difference) and droplet size (<±1.5% difference), indicating a weak dependence of the gas phase density on two-phase atomization. This confirms that laboratory experiments on effervescent nozzles using air have reliable similarity to systems that use high temperature steam for the gas phase. [Copyright &y& Elsevier]

Raw pineapple leaf fibers (PALFs) were chemically modified by scouring, NaOH treatment, and bleaching (NaClO2). The graft copolymerization of synthetic acrylonitrile monomer onto bleached PALFs was carried out in aqueous medium using potassium persulfate (K2S2O8/FeSO4) as a redox initiator. The maximum grafting level at optimum conditions, namely, monomer concentration, initiator concentration, catalyst concentration, reaction time, and temperature have been determined. The main objective of this study is to decrease the amorphous region of lignocellulose in PALFs and improve its hydrophobic nature by incorporation of synthetic polymer of polyacrylonitrile and mechanical properties. The modified and grafted fibers were characterized by Fourier transform infrared spectroscopy, scanning electron microscope, thermogravimetric analysis, and X-ray diffraction study techniques. The moisture content and tensile strength properties were also evaluated for their environmental and mechanical performances. [ABSTRACT FROM AUTHOR]

Abstract: In this study, CuO/CeO2 catalysts with a Cu content ranging from 5% to 40% were synthesized by sol–gel Pechini method and were tested in a fixed-bed reactor for water gas shift (WGS) reaction. The catalysts were characterized by XRD, N2 adsorption isotherms at 77K (S BET) and H2-TPR. Based on the catalytic activity results, 10% CuO/CeO2, identified to be the most active catalyst, was deposited inside finger-like regions of an Al2O3 hollow fibre support for the further development of both catalytic hollow fibre micro-reactor (CHFMR) and catalytic hollow fibre membrane micro-reactor (CHFMMR) where Pd or Pd/Ag membrane was coated on the outer layer of the Al2O3 hollow fibre using a single or multilayer electroless plating (ELP) technique. The prepared catalytic membranes were characterized by SEM, EDX, and pure H2 and Ar permeation. Also, a comparative study of the CO conversion obtained in the WGS reaction as a function of the reaction temperature (from 200°C to 500°C) in a fixed-bed reactor, a CHFMR, a Pd-CHFMMR and a Pd/Ag-CHFMMR, was performed showing that the conversion was highest in the Pd/Ag-CHFMMR. [Copyright &y& Elsevier]

Abstract: Structural and magnetic properties of a series of polycrystalline spinel type ferrites with the nominal chemical composition Li x Mg0.40Ni0.60−2x Fe2+x O4, where x=0.0–0.3 in steps of 0.05, were investigated thoroughly. The formation of spinel structure was confirmed by X-ray diffraction analysis. Lattice constants and average grain diameters increased with increase in Li content. The real part of the initial permeability (μ / i ) is found to increase not only with increase in Li content up to x=0.25 but also with the increase in sintering temperature up to 1100°C. However, it decreases for further increase in sintering temperature except for x=0 and 0.05 compositions. The grain size dependent μ / i is also observed clearly in this research. From the magnetization as a function of applied magnetic field plots, it is clear that all samples exhibit ferrimagnetic state at room temperature and have a low saturation field. The magnetization obtained is explained with the help of redistribution of cations in the tetrahedral and octahedral sites and spin canting due to weakening of exchange interaction. [Copyright &y& Elsevier]

Abstract: Al2O3 hollow fibres fabricated by phase-inversion, followed by sintering at different temperatures (1350, 1400 and 1450°C) have been employed for the further development of a novel catalytic hollow fibre micro-reactor (CHFMR). After depositing with a 10%CuO/CeO2 catalyst, the catalytic activity of the CHFMR has been compared with that of a conventional fixed-bed reactor using water gas shift (WGS) as a sample reaction. The deposition of catalyst into the finger-like voids was carried out using the sol–gel Pechini method. The Al2O3 hollow fibres were characterized before and after catalyst deposition by BET surface area analysis, Hg porosimetry and SEM–EDS. The catalytic activity tests were performed at P =1atm and between T =200 and 400°C. It has been observed that the dispersion of the 10%CuO/CeO2 catalyst within the Al2O3 hollow fibres is strongly dependent on the physical and chemical properties of the fibre surface, which are determined by the sintering temperature. Finally, an increase of 20% in the CO conversion of the WGS reaction was observed for the CHFMR when compared with a conventional fixed-bed reactor, since the finger like structure of Al2O3 hollow fibres (D p =10μm) acts as a micro-reactor and improves the heat and mass transfer, and the mixing of gases during the reaction. [ABSTRACT FROM AUTHOR]

Abstract: This article describes development of a catalytic hollow fibre membrane micro-reactor (CHFMMR) for high purity H2 production. Asymmetric Al2O3 hollow fibres produced by a phase-inversion and sintering technique were employed as a single substrate for both coating of the Pd membrane and impregnation of the 30%CuO/CeO2 catalyst. The Pd membrane was first deposited onto the outer layer of Al2O3 hollow fibre using the electroless plating (ELP) technique, followed by impregnation of the 30%CuO/CeO2 catalyst into the inner finger-like structure of the substrate using the sol–gel Pechini method. Performance of the proposed reactor was carried out using water gas shift (WGS) reaction as a sample reaction. A comparative study of conversion obtained in the WGS reaction as a function of the reaction temperature (from 200°C to 500°C) in a fixed-bed reactor, a catalytic hollow fibre micro-reactor (CHFMR) and the CHFMMR using different flow rates of a sweep gas (from 45 to 70ml/min) was performed, concluding that the conversion is the highest in the CHFMMR. It is important to highlight that, at 500°C and a sweep gas flow rate of 75ml/min, a conversion of 17% higher than the corresponding thermodynamic equilibrium conversion was achieved in the CHFMMR. In the operation of the CHFMMR, high purity H2 has been obtained in the shell side, which was 78% of the total H2 produced in the WGS reaction. [ABSTRACT FROM AUTHOR]

Abstract: A novel catalytic hollow fibre membrane microreactor (CHFMMR), consisting of a thin Pd layer and a 30%CuO/CeO2 catalyst supported on an asymmetric Al2O3 hollow fibre has been developed. In the preparation of the CHFMMR, the Pd layer was deposited on outer surface of the hollow fibre substrate by electroless plating first, followed by impregnation of 30%CuO/CeO2 catalyst in the finger pores located in the inner surface of the hollow fibre lumen by sol–gel coating. The catalytic activity of the CHFMMR was tested using water–gas shift (WGS) reaction and compared to that of a catalytic hollow fibre microreactor (CHFMR) and a conventional fixed-bed reactor. The catalytic activity tests were performed at 1atm and from 200°C to 500°C using different flow rates of sweep gas (from 50 to 75ml/min). The ratio between CO and H2O in the feed was 1 to 0.5 with a space velocity of 80lg−1 h−1. The conversion obtained in the CHFMMR is 35% higher than that in the conventional fixed-bed reactor. Furthermore, a conversion which was 17% higher than the corresponding thermodynamic equilibrium conversion was achieved in the CHFMMR, at 500°C with a sweep gas flow rate of 75ml/min. [ABSTRACT FROM AUTHOR]

Abstract: This is an experimental study of the effects of liquid viscosity (μL ) and surface tension (γ) on the size of droplets produced by an atomizer fed with a two-phase gas/liquid (TPGL) mixture. The nozzle is a one-quarter scale model of an industrial fluid coker nozzle used for bitumen upgrading. The primary objective of this study was to compare the Sauter mean diameter of the TPGL sprays for different μL and γ. Compressed air was used as the gas phase; the liquid phases were water, canola oil and a glycerine–water solution. The μL was varied from 1mPas to 67mPas, and γ was varied from 25mN/m to 61mN/m. The liquid flow rates were varied from 0.095L/s to 0.105L/s, and the gas-to-liquid ratio , by mass, was fixed at 2%, similar to the ratio used in commercial fluid coker nozzles. Fluid mixing pressures in the test were between 400kPa and 700kPa. The D 32 within the spray was measured using a Dantec 2D-Fibre mode Phase-Doppler-Particle-Anemometer (PDPA). With measurements performed at axial distances of 100 and 202mm from the nozzle orifice and within a spray radius of 40mm. The results showed that the 67-fold increase in μL results in 46μm increase in D 32 which roughly extrapolates to a power law relationship exponent of 0.11 (based on two points). In contrast, the 2.4-fold increase in γ indicates roughly 42μm increase in D 32, giving an exponent of −0.24. For both parameters the exponent is small, indicating weak dependence. The γ effects appear stronger, but the modest increase is barely exceeds the margin of error. [Copyright &y& Elsevier]

Abstract: Anion formation by electron impact from CF4 has been studied experimentally in the range 0–30eV electron energy. F− and CF3 − anions were observed while F2 − ions, if any, were below the detection limit. The resonance peaks for F− and CF3 − were measured to be 6.5 and 7.1eV, respectively. Only F− is produced via the ion pair formation channel and the yield varies monotonically with energy above the threshold. [Copyright &y& Elsevier]

Abstract: PAN fibers were fabricated using a solvent-free coagulation process and characterized using SEM and tensile testing. Eighteen weight percent of polymer solution was found to be the most suitable composition for fabrication process and consequently produced fibers with the best mechanical properties. The PAN fibers fabricated using a coagulation bath temperature of 13°C exhibited the highest Young''s modulus of 2.93GPa and the highest tensile strength. The number of nano-pores was significantly reduced due to low inward diffusion of non-solvent. [Copyright &y& Elsevier]

Abstract: The objective of this work was to produce renewable liquid fuel (bio-oil) from locally produced bagasse by pyrolysis in a batch feeding and fixed bed reactor. The experiments were performed at different temperatures ranging from 300 to 600°C. The bio-oil was collected from two condensers of different temperatures and defined as oil-1 and oil-2. The maximum total yield of bio-oil was found to be 66.0wt% based on bagasse. The carbon based non-condensable gases were CO, CO2, methane, ethane, ethene, propane and propene. The density and viscosity of oil-1 were found to be 1130kg/m3 and 19.32 centipoise and that were 1050kg/m3 and 4.25 centipoise for oil-2, respectively. The higher heating values (HHV) of them were 17.25 and 19.91MJ/kg, respectively. The pH of the bio-oils was found to be around 3.5 and 4.5 for oil-1 and oil-2, respectively. The water, solid and ash contents of oil-1 and oil-2 were determined and found to be around 15, 0.02 and 0.03wt% and 11, 0.01 and 0.02wt%, respectively based on bagasse. [Copyright &y& Elsevier]

Abstract: Conventional methods of perforation by shooting (PS) cannot achieve the expected wellbore productivity due to the presence of a region of reduced permeability around the perforation tunnel. Even though this phenomenon is well-known in the petroleum industry, few have attempted to quantify the damage due to PS. This paper quantifies the permeability damage followed by the recommendation of a novel perforation technique. This study has established that permeability of an open-hole is reduced in the range of 30%–75% due to the implementation of the PS technique. In order to remedy this problem, a new perforation technique called perforation by drilling (PD) has been proposed in this paper. To simulate a perforated completion, cylindrical sand samples with varying strength and porosity were prepared. These samples were perforated by the PS, PD and Casting techniques. Perforations created by the Casting techniques are considered to be representative of open-hole perforation tunnels. An important measure of flow efficiency or productivity of perforation completions can be referred to as skin factor (s) and productivity index (PI). In this paper, the performance of the PS, PD, and Casting technique was evaluated in terms of skin factors. Experimental results suggest that the skin factor is reduced substantially when the PS technique is replaced by PD technique resulting in significant improvement in PI. Finally, a mathematical model is used to predict permeability values with various perforation techniques. The mathematical model results agree closely with experimental observation. [Copyright &y& Elsevier]

Abstract: The paper reports the fabrication and characterizations of PAN fibers fabricated using residence time in the range of 2–5s in the solvent-free coagulation process. The PAN fibers were characterized using SEM, FTIR-ATR and tensile testing. The SEM photographs revealed that the cross-section of PAN fiber for all samples were free from large voids. A residence time of 3s was found to be the most suitable residence time for fabricating the PAN fibers in the solvent-free coagulation bath. FTIR-ATR data suggest that the PAN fibers possessed better molecular orientation and exhibited the highest Young''s modulus of 2.55GPa. [Copyright &y& Elsevier]

The tilapia fish (Oreochromis niloticus) has an important place in the aquaculture of the developing world. It is also a very useful laboratory animal, and readily lends itself to the transgenic technology. Through the use of reporter genes, a range of potential gene promoters have been tested in tilapia, both through transient and stable expression of the reporter construct. Using the transgenic technology, growth enhanced lines of tilapia have been produced. These fish have no abnormalities and offer a considerable growth advantage for future exploitation. It is however crucial that transgenic fish, to be exploited in aquaculture, be sterile, and various methods of achieving sterility are considered. These include triploidy, gene knock out of crucial hormone encoding genes via homologous recombination, and knock down of the function of the same genes via ribozyme or antisense technologies.Transgenic tilapia also offer the potential for exploitation as biofactories in the production of valuable pharmaceutical products, and this is also discussed. [Copyright &y& Elsevier]

A combination of biodiesel with hydroxy is expected to be one of the most viable fuels to enhance engine performance besides stringent emission norms. In this study, biodiesel was produced from water hyacinth and injected into the engine along with HHO in a volumetric ratio of 40% (BD40). The test was performed in a 4-stroke cycle, single cylinder, and water cool CI engine to evaluate performance, emission, combustion, and heat loss characteristics. The maximum biodiesel yield of 87% was obtained at 1% KOH, 9:1 M ratio, 500 rpm, and 55 °C for 90 min. The engine results showed that a mixture of hydroxy and biodiesel blends caused an increment of BTE by 12.4% while reducing BSEC by 13.5%, HC by 48% and CO by 21.9% as compared to DF. However, the induction of hydroxy increased NOx emission by 47.3% at full operational mode. The peak HHR, peak cylinder pressure, and ID were higher for hydroxy operated engine. The supplementation of hydroxy increased heat loss through the cooling water, and the exhaust. Thus, the present investigation has proved that the induction of hydroxy with BD40 in the CI engine improves performance and reduces exhaust emission like CO and HC except for NOx. • The maximum yield of biodiesel is found to be 87% through transesterification. • The effect of hydroxy on engine performance, combustion, and heat loss is evaluated. • The addition of hydroxy improves BTE and BSEC by 12.4% and 13.5% respectively. • Hydroxy reduces CO and HC by 21.9% and 48% respectively but increases NOx by 47.3%. • Hydroxy increases HHR, cylinder pressure, ID, cooling and exhaust heat loss. [ABSTRACT FROM AUTHOR]

Presents a novel approach of speed control for a permanent magnet synchronous motor (PMSM) using on-line self-tuning artificial neural network (ANN). Motor dynamics and nonlinear load characteristics; Implementation of the complete drive system.

Presents a paper which identifies a novel technique to distinguish between magnetizing inrush and internal fault currents of a power transformer. Basing of the proposed differential algorithm on artificial neural network (ANN); Importance of transformer protection; Details on the experiment and its findings.

Reports on the design and implementation of a stand-alone digital relay, which can be modified easily to accommodate the protection of different types of transformers. Challenges faced by relay designers in the protection of three phase power transformers; Details on the digital relay system which was proposed in the paper.

Presents a modelling and controller design of an isolated diesel engine permanent magnet synchronous generator. Use of a fixed capacitor-thyristor controlled reactor scheme to regulate the generator terminal voltage; Analysis of the steady-state performance of a stand-alone permanent magnet synchronous generator.

• Structural Colouration on the stainless steel surface was done by Al 2 O 3 -Au thin film. • Wide range of structural colours were prepared by the amorphous Au nanocomposite thin film. • The colour range of the crystalline films were limited due to the enhancement of plasmonic effect. • Coluration by disordered films can be explained by polarizonic interference phenomenon. • Colouration by ordered films was explained by Bruggeman theory. Structural colouration of the stainless steel surface was studied by Au-Al 2 O 3 nanocomposite thin film coating. A wide range of colours was achieved by amorphous, i.e. disordered Au-Al 2 O 3 nano composite thin films where four different structural colours, i.e. magenta, blue, yellow-green and orange, were prepared by varying film thickness and composition. In this case, colours were easily tunable by adjusting the thickness of the film. The colouration mechanism of the amorphous films can be explained by polarizonic interference phenomenon. As the samples were annealed, the Au nanocomposite thin films were crystallized and the range of colours became limited to two colours only: dark yellow-green and light orange. During the annealing process, nanoparticles became enlarged and plasmonic effect caused the limitation of the colour range. Bruggeman theory was applied to predict the colours if the annealed samples. [ABSTRACT FROM AUTHOR]

Suspension-feeding bivalves are the keystone species that affect the abundance and composition of phytoplankton communities. This study compares the food selectivity of oysters Crassostrea gigas (Thunberg, 1973), mussels Mytilus galloprovincialis (Lamarck, 1819), and cockles Katelysia rhytiphora (Lamy, 197) on natural particle assemblages in the laboratory using water collected from Coffin Bay, South Australia, in spring, summer, autumn and winter. The phytoplankton community was dominated by Bacillariophyceae (diatoms), Dinophyceae (dinoflagellates) , Synechococcus (cyanobacteria) , and picophytoplankton (2–5 μm) from September 2016 to August 2017. Diatoms and picoplankton, including cyanobacteria, were dominant in spring and summer, while dinoflagellates were dominant in autumn and winter. Oysters and mussels selectively fed on large food particles (e.g., diatom, dinoflagellate and large picoplankton > 2 μm) regardless of season, but mussels could access a wider size spectrum of food particles compared to oysters. In contrast, cockles selected for both large and small food particles (e.g., Synechococcus and small picoeukaryotes < 2 μm) and fed more efficiently on small particles than both oysters and mussels. Bacteria were more abundant in warmer seasons, but mussels and cockles selectively reduced bacterial abundance. The abundance of virus-like particles was not affected by season nor by filtration of any molluscan species. This study demonstrates that oysters and mussels utilise similar food sources, whereas cockles consume a large range of food particles. Additionally, these three molluscan species do not necessarily compete for food; hence, stocking multiple filter-feeding species in an ecosystem could exploit a wider spectrum of food particle size and increase system productivity. • Oysters and mussels utilise similar food sources in the water column, but cockles consume a large range of food particles. • Oysters, mussels and cockles do not necessarily compete for food. • Stocking multiple filter-feeding species in an ecosystem can effectively use a wider range of food particles. • The abundance of virus-like particles was not affected by any molluscan species. [ABSTRACT FROM AUTHOR]

Pseudophrynamine, lunacridine and the new compound 2-(2′,4′,6′-trimethyl-heptenyl)-4-quinozolone were isolated from the leaves of Zanthoxylum budrunga. [Copyright &y& Elsevier]

The miniaturization of electronic devices has facilitated increasing interest in new applications of wireless communication. In this paper, a new miniature microstrip fed boomerang-shaped patch antenna has been proposed and designed for a wireless sensor network (WSN) application. In this design, the proposed antenna possesses a wide bandwidth by loading of a boomerang-shaped patch; with a 50 Ω microstrip feed line and a partial ground plane. A one-step staircase slot is embedded in the ground plane to enhance the impedance matching over a wide frequency range. The antenna occupies a small size of 10 × 12 mm2, or 1.2 cm2. The simulated results are verified with measured results. The measured result shows that the achievable bandwidth of 69% (8.48–17.45 GHz). The antenna possesses stable radiation patterns and acceptable gain. The proposed low profile antenna is suitable to integrate with sensors for wireless sensor network in X-band and Ku band applications. [ABSTRACT FROM AUTHOR]

Four types of liquid‐metal‐based tunable capacitors with a high tuning range are demonstrated. The capacitors are easily fabricated by placing a pair of liquid‐metal‐filled tubes in contact with one another. Tunability is achieved by varying the length of the liquid metal in one of the tubes using a mechanical pump. Four different structures are demonstrated: parallel‐tube, folded‐tube, coil, and spiral capacitors. The highest measured tuning ratio is 42:1, and the highest change in capacitance per unit length of the pumped liquid metal is 0.07 pF/mm. [ABSTRACT FROM AUTHOR]

Plant extracts have recently been used as exogenous adjuvants to strengthen the endogenous plant defense systems when they grow under different environmental stresses, including salinity. The study aimed at determining the effects of seed soaking using licorice root extract (LRE) on photosynthesis and antioxidant defense systems, including transcript levels of enzyme-encoding genes in pea seedling grown under 150 mM NaCl-salinity. Salt stress reduced seedling growth, photosynthesis attributes, and K+ content, and increased oxidative stress (O 2 •‒ and H 2 O 2 , and MDA), Na+, and Cl−, along with an increase in antioxidative defense activities compared to control. However, LRE pretreatment enhanced seedling growth, photosynthetic attributes (chlorophylls, carotenoids, Fv/Fm, Pn, Tr, and gs), ascorbate and glutathione and their redox states, proline, soluble sugars, α-TOC, and enzyme activities compared to stressed control. LRE pretreatment also upregulated transcript levels of CAT -, SOD -, APX -, GR -, DHAR -, and PrxQ -encoding genes in salt-stressed seedlings, decreasing oxidative stress and Na+ and Cl− contents and increasing K+ content and K+/Na+ ratio. • Licorice root extract (LRE) improved growth of salt-stressed pea seedling. • Enzymatic and non-enzymatic antioxidants activities were improved by pretreatment using LRE. • LRE upregulated the transcript level of enzyme-encoding genes in pea seedlings under salt stress. • LRE effectively reduced oxidative stress (H 2 O 2 and O 2.•‒ levels) in salt-stressed pea seedlings. • LRE pretreatment effectively restored K+ content and reduced Na+ content, thus increasing K+/Na+ ratio. [ABSTRACT FROM AUTHOR]

An understanding of the transport and dynamics of two fluids in porous media, as well as the bubbly flow regime, is important for many engineering applications, such as enhanced oil recovery (EOR) method, drilling technology, multiphase production system, etc. In this respect, the dependence of capillary stresses on the excess free-energy of a thin interfacial layer formed by two immiscible fluids is not fully clear, particularly in porous media. Of particular interests are the closure models for interphase forces which often hinder the reliable prediction of the homogeneous flow regime. This article presents a multiphase Computational Fluid Dynamics (CFD) study of bubbles in homogeneous porous media to model the flow of oil and gas, and investigates a closure model that is based on the Allen-Cahn phase-field method, where the capillary stress is derived from the excess free-energy. The governing dynamics is simulated with the volume averaged Navier-Stokes equations extended for multiphase flow in porous media. The equations have been discretized by a wavelet transform method to accurately capture the topological change of the fluid-fluid interface. To validate the closure model for interphase forces, the results of the present phase-field method have been compared with that from experiments, as well as from reference numerical models. An excellent agreement among the results from present phase-field simulations, experiments, and some reference numerical simulations has been observed. The terminal velocity of the rising gas bubble in a liquid saturated porous medium, as well as in a pure liquid has been investigated. The bubble rising velocity in both cases have been compared with respect to the theoretical and experimental results. The study illustrates how the bubble dynamics in porous media depend on the excess free energy of a thin interfacial layer formed by two immiscible fluids. [ABSTRACT FROM AUTHOR]