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The construction industry had approached a critical limit which led to the increase of cement production. The production of cement would cause a broader environmental implication. Cement production is a major source of carbon dioxide emission. Carbon dioxide gas contributes about 63.33% of global warming since the production of one ton of cement would emit about one ton of carbon dioxide to the environment. To mitigate this issue, the research community has investigated the use of waste materials that possess similar chemical properties with cement content as a material for partial cement replacement. The use of rice husk ash has shown to be a contending candidate in the literature. Therefore, this paper attempts at reviewing the performance of rice husk ash as partial cement replacement. It could be observed from the literature that concrete with 5% up to 15% of rice husk ash showed an equivalent performance to ordinary concrete in compressive, flexural, and tensile strength. Thus, rice husk ash can be used as a material replacement in concrete and reduces pollution that originates from cement production and open burning of rice husk.

Membrane heat exchangers were used for moisture and heat recovery from a hot and humid natural gas stream in indirect contact with an air stream. A plate membrane module with spiral channels on each side was designed to configure gas and air streams in co-current and counter-current flow. Two types of membranes, a commercial kraft paper, and a laboratory-made thin-film composite membrane, were used as the module core. The thermal efficiency and the water recovery from the humid gas were calculated and compared under different operating conditions. At a unit flow ratio of air/gas, the greatest effectiveness was achieved at a methane flow of 100 cm3/min, but water recovery increased at higher gas flows. For the counterflow configuration, an air/methane flow ratio of 2 was sufficient to achieve the highest total effectiveness and water recovery; however, larger air/gas ratios were beneficial to improve heat and moisture transfer for the co-current configuration. The highest water recovery by the kraft paper and composite membrane was achieved (approximately 15 mgH2O/cm2.h) for the input gas with the highest humidity. The dehumidification performance of kraft paper as a porous and hydrophilic membrane was slightly better than that of the composite membrane containing a dense hydrophilic polymer thin film in most cases. A relatively low heat transfer coefficient was found for the module, which was increased by using higher gas flow rates at higher humidity conditions.

Coconut Shell is a waste product derived from agriculture which is utilized as bio adsorbent for treating the wastewater discharged from electroplating industries. The physio chemical characterization of raw waste water and batch adsorption study using coconut shell charcoal (CSC) with a reference to effluent characterization is conducted to identify the potential contaminant and efficiency of adsorbent. The parameters such as effective particle size of adsorbent, contact time and dosage influencing the treatment efficiency of zinc and potassium which are identified as the potential contaminant in the waste water. Increase in dosage and specific surface area with reduced particle size increases the treatment efficiency up to the approved level, beyond which the portion adsorbed which remains constant. It is apparent that a dosage of 15 g/l and duration of 90 min is satisfactory to remove 90% of phosphate and 97% of zinc for 150 µm particle size. The adsorption equilibrium data were tailored well with the Freundlich isotherm for the removal of zinc and potassium. The baseline study is manifested the potential of CSC in the reduction of zinc and potassium from the industrial waste water.

Acid pretreatment is one of the most widely used fractionation processes for lignocellulosic biomass. In this study, effect of mineral acids (SA, HA, and NA) on recovery of reducing sugar from coconut coir was studied. The independent variables such as reaction time (X1, min) and concentration of acid (X2, % w/w) were optimized using Response Surface Methodology (RSM) for maximum yield of reducing sugar. In this study, 10% w/v of coir was pretreated under various conditions of X1 and X2 by maintaining a constant temperature (121oC). A maximum reducing sugar yield greater than 55% was observed for acid pretreatment.

Microalgae-bacteria symbiotic association can provide many competitive advantages over the pure axenic culture of microalgae to obtain biofuel. This system significantly reduces an important technical constraint, including associated capital cost with the infrastructure required for maintaining pure microalgae culture. The current study aims to compare the symbiotic growth of Tetraselmis indica - Pseudomonas aeruginosa consortium with axenic growth of Tetraselmis indica in dairy wastewater (DWW). The extraction and optimization of chlorophyll-a were also investigated. The overall maximum chlorophyll-a recovery of 29.106 ± 0.045 mg L−1 was obtained through the sonification as extractant method with methanol as an extraction solvent. The chlorophyll-a content of consortium cultivated in DWW higher than the axenic pure microalgae culture (APMC). The maximum biomass yield of the consortium was achieved as 1454.88 mg L−1, which is much higher than APMC growth in DWW by 38.80%. On the 10th day, the consortium removed 87.49%, 83.76%, and 79.83% of chemical oxygen demand (COD), total dissolved nitrogen (TDN), and total dissolved phosphorus respectively. The higher biomass growth and wastewater nutrient removal exhibited by the symbiotic microalgae-bacteria consortium can be utilized in biofuel technology.

Bentonite is a favourable candidate as a sealing material in the deep geological repository to safe storage of highly radioactive nuclear waste in several countries. The high swelling characteristic made bentonite famously type of clay that extracted from smectite group with the main mineral is montmorillonite that has a double diffusion layer. The benefits of sodium bentonite like Wyoming bentonite has proven in the industry. Research on modifying the properties of calcium bentonite to high swelling clay like sodium bentonite for it be able to benefit the industry has been done. Most of the research attempted to improve the workability of calcium bentonite as an alternative material for replacing sodium bentonite in construction industry; however, very little is known about using raw calcium bentonite to improve weak soil subgrades. This paper highlighted the usage of calcium bentonite adapted in construction industry especially in soil stabilization activity and some experimental analysis has been made on the type of calcium bentonite found in British Columbia mine.

21 p.-14 fig. In Memoriam Prof. Kilian Muñiz (R.I.P.). Excellent person, great heart., The innate immunity TLR4/MD-2 system is a membrane receptor of paramount importance as therapeutic target. Its assembly, upon binding of Gram-negative bacteria lipopolysaccharide (LPS), and also dependent on the membrane composition, finally triggers the immune response cascade. We here combine ab-initio calculations, molecular docking, all-atom molecular dynamics simulations, and thermodynamics calculations to provide the most realistic and complete 3D models of the active full TLR4 complex embedded into a realistic membrane to date. Our studies reveal functional and structural insights into the transmembrane domain behavior in different membrane environments, the ectodomain bouncing movement, and the dimerization patterns of the intracellular TIR domain. Our work provides TLR4 models as reasonable 3D structures for the (TLR4/MD-2/LPS) 2 architecture accounting for the active (agonist) state of the TLR4, and pointing to a signal transduction mechanism across cell membrane. These observations unveil relevant molecular aspects involved in the TLR4 innate immune pathways and will promote the discovery of new TLR4 modulators., This work was financially supported by the Spanish Ministry for Science and Innovation (grants CTQ2014-57141-R, CTQ2017-88353-R, and PID2020-113588RB-I00; grants BES-2012-053653 for L.P.R., BES-2015-071588 for J.G.C. and PRE2018-086249 for A.M.R.), and the European Commission Marie Sklodowska-Curie actions (H2020-MSCA-ITN 642157 “TOLLerant”).

In recent years, agricultural wastes cause serious pollution to the environment. Agricultural residues can be used to produce value-added products in order to control environmental pollution, therefore these wastes are a promising feedstock as it has many advantages such as wide range of source, low cost and renewable. Rice straw and lemongrass leaves which are the renewable sources for the production of many useful products such as xylose. The aim of this study is to compare the content of xylose produced from rice straw and lemongrass leaves, in order to obtain highest yield of xylose and to optimize the acid hydrolysis time, concentration of sulphuric acid, liquid–solid ratio and the power of the microwave towards the maximum extraction of xylose. Microwave assisted acidic hydrolysis method was used to extract xylose from rice straw and lemongrass leaves. The acid hydrolysis of both rice straw and lemongrass was performed at different time (1–5 min), acid concentration (1%–5%), liquid solid ratio (1:30, 2:30, 3:30, 4:30 and 5:30) and power (160 W, 320 W, 480 W, 640 W, 800 W). The results obtained indicate that the yield of xylose from rice straw (2.98 g/L) via the microwave assisted is slightly higher than lemongrass (2.91 g/L) with optimum conditions of 3 min of hydrolysis time, 2% of sulphuric acid concentration, 1:30 of liquid solid ratio and 320 W of microwave power. Meanwhile, the optimum conditions for lemongrass leaves are 4 min of hydrolysis time, 4% of sulphuric acid concentration, 2:30 of liquid solid ratio and 480 W of microwave power. Thus, rice straw has slightly higher capability in production of xylose compared to lemongrass.

Drilling Slurry or drilling mud is used to stabilize the drilled wellbores. Unfortunately, its disposal on land renders the soil infertile, while its coagulation with aluminium salts poses potential health risks. Here, two natural coagulants: Moringa oleifera and Benincasa hispida were investigated as potential sustainable alternatives to chemical coagulants. These are cost-effective, highly biodegradable, and safe from the human health point of view. Various forms of these substance: seed powder, de-oiled seed powder, and seed oil were used to minimize the drilling mud slurries. For the turbidity removal, the best efficiency of 99.71% was obtained by using de-oiled seed powder of Benincasa hispida whereas the total solids removal efficiency of 94.19% was obtained by using de-oiled seed powder of Moringa oleifera at an optimum dosage of 10 g/l. These results are comparable to those obtained by using alum, thus confirming the effectiveness of the natural coagulants for management of drilling slurries.

Dyes derived from coconut (Cocos nucifera) husk have materialised as an important substitute to synthetic dyes. However, better extraction techniques are needed to leach out the natural colourants from this plant. The influence of sodium hydroxide (NaOH) concentration (0.2 to 0.8 M) and time of extraction (2 to 10 min) on the maximum extraction yield of natural dye from the mesocarp and exocarp of C. nucifera have been studied. The results indicate a significant (p

The huge packaging application of non-degradable plastics has created a severe threat to the present civilization. This work emphasizes on low density polyethylene/corn starch biopolymer sheets production. Biodegradability assessment was done under alkali, acid, compost pit soil, garden soil and vegetable waste environment for one year. Enhancement in starch content by 60% in the matrix improved the Young’s modulus and stiffness from 251.79−422.42 MPa and 17763.34–27481.87 N/m respectively. Highest increase in weight loss percent from 1.26% for virgin LDPE to 13.18% for the sample LC5 (LDPE-16 g, Starch-24 g) was observed in garden soil. The degradation was also reported by morphological non-uniformness (SEM images) and drop in mechanical properties like tensile strength from 7.9 to 2.12 MPa in vegetable waste environment. Increase in haze from 97.20 to 99.8% and decrease in transmittance from 68.40 to 28.20% in vegetable waste for sample LC5 confirmed the optical degradability of the sheets.

Various detrimental effects of petroleum-based lubricants have encouraged the use of vegetable oil as a replacement due to its better lubricity and environmental friendliness. This study evaluated the performance of virgin and emulsified vegetable oil as cutting fluid for the turning of titanium alloy with ceramic inserts. The performance was determined using signal to noise (S/N) ratio with few input parameters such as lubricant type, cutting speed, feed rate, and depth of cut. Palm oil and coconut oil were used as the vegetable oil. The virgin oil was mixed with a portion of water to produce emulsified oil. The machining operation applied minimum quantity lubrication (MQL) throughout the experiment. The performance of each type of oil was evaluated in terms of S/N ratio for cutting temperature, and chip reduction coefficient, and percentage of cutting tool wear in order to obtain the best cutting condition. Results showed that the virgin palm oil had better performance on the cutting temperature, tool wear, and chip reduction coefficient. Furthermore, the virgin coconut produced better performance compared to emulsified coconut oil. Hence, it is concluded that virgin vegetable oils perform better as cutting fluid compared to emulsified vegetable oil.

The present study reports the effectiveness of natural plant materials - fenugreek as a coagulant, with okra and Aloe vera as flocculants, to treat palm oil mill effluent (POME). The treatment process was modelled using Central Composite Design (CCD) of the Design Expert software. Standard jar tests were used to determine the important treatment parameters such as pH, coagulant dosage and flocculant dosage on the removal efficiencies and they were optimized with Response Surface Methodology (RSM). The optimum condition obtained from RSM was established for pH, coagulant dosage and flocculant dosage as pH 4, 22.24 g/L and 16.77 mL/L respectively for fenugreek-okra, and pH 4, 24.13 g/L and 20 mL/L respectively for fenugreek-Aloe vera. Removal efficiencies of TSS, TUR and COD were 88.19%, 78.35% and 30.56% respectively for fenugreek-okra and 83.40%, 82.78% and 32.95% respectively for fenugreek-Aloe vera. Results obtained from characterisation shows that the coagulation – flocculation process was ruled by inter-particle bridging as the dominant mechanism.

The liquid green hydrocarbons (LGHs) fuel was collected from waste tube-tyres by the pyrolysis process using FeCO3 a catalyst; it was conducted at 23 to 370 °C. The LGHs fuel were characterized by FT-IR, 1H NMR, GC × GCMS, Parameters of diesel, and ICP. Fractions of LGHs, gases, and residues were obtained from 100 gm, 98 gm, and 95 gm waste tube-tyres with 0 gm, 2 gm, and 5 gm. Waste tube-tyres whose rates of conversion percentage in LGHs 50%, 52%, and 56% gases were 12.52%, 10.52%, and 13.55% residues were 37.48%, 26.48%, and 30.45%. Sulfur percentage, and 23 types of metal elements were obtained in LGHs were less than their standard limits. Physicochemical properties of LGHs fuel were found to be close their standard limits.

Calculating polarizabilities of large clusters with first-principles techniques is challenging because of the unfavorable scaling of computational cost with cluster size. To address this challenge, we demonstrate that polarizabilities of large hydrogenated silicon clusters containing thousands of atoms can be efficiently calculated with machine learning methods. Specifically, we construct machine learning models based on the smooth overlap of atomic positions (SOAP) descriptor and train the models using a database of calculated random-phase approximation polarizabilities for clusters containing up to 110 silicon atoms. We first demonstrate the ability of the machine learning models to fit the data and then assess their ability to predict cluster polarizabilities using k-fold cross validation. Finally, we study the machine learning predictions for clusters that are too large for explicit first-principles calculations and find that they accurately describe the dependence of the polarizabilities on the ratio of hydrogen to silicon atoms and also predict a bulk limit that is in good agreement with previous studies.

The effect of dry grinding on the oxidation features of 304L stainless steel (SS) in simulated primary water of BWR and PWR was studied. The objective is to demonstrate the influence of mechanical surface treatments on surface state and oxidation behavior of the SS. Thus, the oxide formed on a ground surface and two polished surfaces (down to 2400 with SiC emery paper and with colloidal silica) had been compared. Subsurface characterizations were first performed to describe the microstructural modification induced by the surface treatment. Then, the morphology and the composition of the oxides' duplex structure were characterized by either scanning electron microscopy, transmission electron microscopy or X-Ray photoelectron spectrometry. Finally, the reactivity of the oxidized surfaces was determined ex-situ by a recently developed electrochemical technique based on electrochemical Impedance spectroscopy and Mott-Schotcky approach. The mechanical surface treatment mainly influences the thickness and doping density of the inner oxide; and the composition and morphologies of the outer oxide-hydroxide precipitates in terms of shape and size. This work evidences that the thinner the inner oxide, the higher the doping density. Besides, the impact of the considered environment on oxidation features is also discussed.

Agroindustrial wastes and by-products from crops can be used for the extraction of valuable components such as pectins, contributing to sustainability and environmental protection. Pectins are complex polysaccharides of the plant cell-walls where fulfill important biological functions, showing high hydration capacity, swelling, thickening, and gelling effects. These features are also of technological interest to the food and pharmaceutical industries. Pectin extraction by conventional techniques involves high-temperature stages and the use of mineral acids which cause deteriorating reactions, loss of functionality, and decreased yield. The acidic and/or alkaline waste streams generated produce environmental pollution and additional costs for effluent treatments. Ultrasound-assisted extraction of pectin allows using less solvent and reduces the environmental impact in terms of energy and time. The present paper reviews some selected bibliography published in the last years concerning the pectin isolation from agroindustrial by-products by means of ultrasound-assisted techniques. A brief revision about pectin structure including the latest results published in relation to interactions with other cell-wall polymers is presented to understand to what extent pectins are modified by the extractive conditions used. The incidence of ultrasound on the yield, chemical structure, molecular weight, and functional properties is discussed concluding that more systematic studies that consider not only the yield but also the process conditions, the chemical composition of the extractant, the chemical structure and functionality of the product, are necessary to have a solid database for process optimization. Moreover, ultrasound combined with other non-conventional techniques can help achieve an efficient extraction, minimizing non-desired changes.

Pectins from Araca (Psidium cattleianum Sabine) fruit pulp were extracted, purified and isolated, obtaining the Araca Purified Pectin (APP) under its sodium form. Yield was found 3.5% w/w of the initial dried material. From titration, monosaccharide analysis after total hydrolysis and 1H and HSQC NMR analyses, it was established that the pectins are formed of long galacturonic acid blocks (HG) partially methylated (degree of methyl-esterification – DM = 55.9 mol%) and acetylated (2 mol%) and RG-I blocks with side chains containing mainly arabinose and galactose. No gelation was observed in presence of calcium for the unmodified APP. Then, pectins were treated in alkaline conditions to de-esterify progressively the initial sample down to DM = 0 after 60 min of treatment. Each sample obtained was characterized by SEC and NMR demonstrating the stability of the main chains, where Rha, GalA and Mw remained unchanged independently of the length of alkaline treatment. One of this sample (APP-15) was selected to test the gelling ability and rheological behavior. The gel was formed by dialysis against 1 mol L−1 CaCl2 and its rheological study allows to conclude that a homogeneous physical gel is formed stabilized by cooperative GalA−-Ca+2 junctions.

Pectins extracted from sugar beet pulp are promising additives for the food and beverage industry due to their good emulsifying properties. However, the relationship between molecular structure and emulsifying properties is still not fully understood; thus, systematic optimization of pectin extraction for a better emulsifying activity is not possible. In this study, we assess the underlying relationship between molecular structure and emulsifying properties by linking relevant structural parameters of 43 acid-extracted sugar beet pectins to their emulsifying properties. Sugar beet pectins with distinct structural characteristics were produced by acid extraction using varying conditions. The extracted polysaccharides were used as emulsifying agents in oil-in-water emulsions. Resulting droplet sizes were measured to correlate molecular characteristics with emulsifying properties. Analyses of protein content, degree of methylation, degree of acetylation, mean molecular weights, and trans-ferulic acid contents showed that these parameters affect the emulsifying properties to some degree, but cannot fully explain the differences observed among all pectins. However, a linear correlation between the proportion of neutral sugar side chains and droplet sizes was observed. The influence of galactose (18–30 mol%) was negligible, but increasing amounts of branched arabinans (up to 57 mol% arabinose) positively affected the emulsification result. Based on these results, it can be concluded that particularly branched arabinan side chains play an important role in the sugar beet pectin-based stabilization of emulsions. Thus, the arabinose content appears to be a suitable indicator to estimate the emulsifying properties of acid-extracted sugar beet pectins.

The starch isolated from Pouteria campechiana seeds and pulp is the novel underutilized tropical fruit resource. Pouteria campechiana seed starch (PCSS) had higher amylose content (33.65%), peak viscosity (PV) (4612 cP), breakdown viscosity (BDV) (1993 cP), pasting temperature (Tp) (74.45 °C), gelatinization enthalpy (ΔH) (11.06 J/g), gel adhesiveness (−5.15 g-s), relative crystallinity (Rc) (22.68%), and short-range molecular order (0.740) than Pouteria campechiana pulp starch (PCPS) (16.63%, 4288 cP, 544 cP, 70.95 °C, 8.43 J/g, −10.22 g-s, 17.65%, and 0.675, respectively). Contrastingly, PCSS had lower final viscosity (FV) (3651 cP), setback viscosity (SBV) (1032 cP), gel hardness (173.69 g), water absorption capacity (WAC) (95.21%), and average particle size (7.26 μm) than PCPS (5763 cP, 2019 cP, 243.39 g, 122.86%, and 9.21 μm, respectively). PCSS and PCPS had A-type crystalline structures. A principal component analysis disclosed significantly positive correlations between 1047/1,022, amylose, Rc, Tp, ΔH, and Pt (p

After cellulose, pectin is the most abundant plant polysaccharide. For decades pectins have been industrially produced from two types of raw material (citrus peel and apple pomace, by-products from juice industry). However, it has been demonstrated that several unutilised and discarded wastes from agricultural, agroindustry and food industry have potential to produce gelling pectins in accordance with the purity criteria set by FAO and EU. The increasing demand for natural-based ingredients for materials, food and health pointed out for the need of growing the pectin production.

Addition of fibre hydrocolloids to diets is expected to result in altered rates of digesta passage due to structuring effects, and the localised production of short chain fatty acids (SCFA) as fermentation products. However, it is not known whether these effects are similar for extracted and intrinsic plant cell wall fibre types. The purpose of this study was to determine the effect of isolated (apple) pectin and fruit (mango) pulp on gastric emptying (GE), passage rate, and SCFA production along the porcine gastrointestinal (GI) tract. Thirty pigs were fed a starch-based diet with or without addition of either pectin or mango pulp over a 21-day intervention trial. Indigestible solid phase constant markers as well as solid and liquid phase pulse markers (fed 2, 4 or 6 h prior to sampling) were fed to measure apparent mean retention time (aMRT) and GE, respectively. The GI tract was divided into nine sections and analysed for digesta contents, marker recovery and SCFA production. The control diet showed significantly faster GE of the liquid digesta phase compared to solid phase, while the addition of pectin significantly delayed GE of the solid phase. The addition of pectin and mango pulp each increased digesta water content, and the pectin diet significantly decreased aMRT along the small intestine. SCFA content was increased significantly in both isolated pectin and mango pulp diets, particularly in the caecum and large intestine, with the isolated pectin diet favouring butyrate production and the mango pulp diet favouring propionate production.

The synthesis of metallic Nanoparticles (NPs) has gathered utmost interest over the past decades thank to their distinctive properties that build them applicable in several fields further as including science and technology. This main methods utilized in their synthesis are non-environmental friendly. This review paper describes the green methods within the synthesis of biogenic NPs further as their mechanisms involving various plant extracts which are non toxic, environment friendly and value effective. The natural plant extracts contains metabolites like flavonoids, terpenoids, polyphenols, alkaloids, etc which acts as both reduction and stabilization agents for synthesizing biogenic NPs with desired shape and size. During this review paper the employment of assorted plant extracts additionally the employment of bacteria, fungi, proteins within the biogenic synthesis of NPs has been delineated shortly. Ultimately the importance and applications of biogenic NPs has also been expressed.

Magnesium is one of the largely available elements in the earth's crust. It has a low structural density with high specific strength. This unique material property has forced an increase in the use of magnesium and its alloys in various applications pertaining to industrial sector, automobiles, aerospace and biomedical. Since magnesium is a highly reactive metal, it is prone to higher rate of corrosion as compared to its counterparts. Thus, it is essential to analyze the corrosion behavior of magnesium and its alloys in its applications. An appropriate process is to be followed in the design and development of magnesium alloys which overcome the limitations of magnesium and enhance the desired material properties in accordance to their applications. This review paper summarizes the importance of magnesium and its material properties. The influence of various alloying elements on the mechanical properties of magnesium is reviewed. The broad classification of Mg alloys and their behavioral trends are detailed. The corrosion behavior of magnesium and the influence of corrosion products on the material characteristics of magnesium, in aqueous medium, are discussed. The manufacturing techniques of magnesium alloys along with the secondary techniques are also covered. The various applications and the limitations of magnesium in these applications are covered. A complete section is dedicated towards detailing the recent trends of magnesium (Mg) alloys, i.e., the biodegradable nature and applications of Mg alloys. The influence of biocorrosion on Mg alloys and techniques to overcome it have been deliberated. This paper provides a thorough review on recent developments of magnesium with respect to engineering applications.

Carbon origami has been recently reported to enable the fabrication of lightweight, 3D and architected shapes of carbon materials using renewable cellulose paper as the carbon precursor. Here, we characterize the effect of different processing variables on the mechanical stiffness of carbon origami shapes. The study is conducted using a Miura-ori pattern. The processing variables studied here include the geometrical features of the unit cell of a Miura-ori pattern, carbonization conditions, and thickness of the cellulose paper. Change of the carbonization environment exhibits a stronger impact on the density and mechanical properties of the carbon origami structure, compared to the effect of final temperature of the carbonization process. Furthermore, the elastic modulus exhibited a proportional relation to a design angle α and an inversely proportional relation to a folding angle β. The elastic modulus of a carbon Miura-ori further increases with the thickness of the paper used for fabrication of the precursor origami shape. We compare the mechanical stiffness obtained from all the variables, which shows that a combination of α and β exhibits the most dominant effect. Combination of all these effects can potentially lead to fabrication of a carbon origami shape that can exhibit mechanical stiffness superior to state-of-the-art cellular materials at a given low density. Further optimization of the processing parameters is needed to achieve such a carbon origami structure.

This paper delineates a single-step production method of nanostructured diiron boride (Fe2B) and its structural, magnetic and magnetothermal properties. Structurally Fe2B resembles the tetragonal copper aluminide, CuAl2. The samples of nanostructured Fe2B were synthesized by milling Fe and B powders without any pre-treatment. Single phase Fe2B nanoparticles were successfully produced with the crystallite sizes of 68 and 46 nm after milling the powders for 10 h and 20 h, respectively. The saturation magnetization of the samples was found to decrease with increased milling time indicating that the surface spin disorder plays a crucial role in the magnetic properties. The highest saturation magnetization (Ms) of 141 emu/g with low coercivity (Hc) of 48 Oe was obtained for the 10 h milled sample of Fe2B, whereas the 20 h milled sample exhibited Ms and Hc as 129 emu/g and 149 Oe. This paper also presents a detailed information on the total and atom projected densities of state functions as well as the magnetic moment contribution of the individual atoms of Fe and B in Fe2B explaining the strong room temperature ferromagnetic properties contributed by the large number of unpaired 3 d electrons in Fe. The magnetothermal properties of the as-made Fe2B nanocrystals of high magnetic moment were investigated by measuring the rise in temperature as a function of time in the presence of AC magnetic fields. The magnetic Fe2B nanocrystals show significant thermal response with the high specific absorption rate of 172 W/g, demonstrating the advantages of using Fe2B nanocrystals for the application in magnetic fluid therapy for hyperthermia.

International audience; Infrared cameras could serve automotive applications by delivering breakthrough perception systems for both in-cabin passengers monitoring and car surrounding. However, low-cost and high-throughput manufacturing methods are essential to sustain the growth in thermal imaging markets for automotive applications, and for other close-to-consumer applications which have a fast growth potential. Fast low cost infrared lenses suitable for microbolometers are currently already sold by companies like Umicore, Lightpath, FLIR… They are either made of a single inverse meniscus Chalcogenide glass or of two Silicon optics. In this paper, we explore hybrid systems with a large field of view around 40° combining Chalcogenide and Silicon in order to take advantage of both materials. Both are compatible with wafer-level process. Silicon optics can be manufactured by photolithography process and are expected to be more cost-effective than Chalcogenide ones. However they are constrained in shape and sag height. On the other hand, Chalcogenide optics can be collectively molded and could have more free shapes. They are thus more suitable to reach high-demanding performance. So hybrid designs could be seen as a compromise between cost and performance. In this paper, we show that fast lenses with diameter constraints to few millimeters to make affordable wafer-level process lead to small size detectors. As a consequence, the pixel pitch reduction of microbolometers is a key point to maintain a good resolution. Finally, strategies to improve the production yield of hybrid lenses are explored.

International audience; Thermomechanical simulation is challenging for the optimization and virtual monitoring of high temperature shape processes, such as SuperPlastic Forming (SPF) of Titanium alloys alike Ti-6Al-4V (TA6V). Part of this challenge is the accurate and process-representative knowledge of emissivity, which controls radiative heat transfer during the process. In this paper, the characterization of TA6V emissivity, with regards to its oxidation stage, is performed within the [600–1000 °C] thermal range. The main contribution of this work is the use of an in-house characterization bench, enabling the fast radiative heating of samples, and the control of oxide layers thicknesses ranging from 250 nm to 120 µm. An oxidation law is established thanks to post-mortem mass gain and oxide thicknesses measurement, and the various oxide phases are identified. Oxide thicknesses versus heating time were then calculated and implemented in the emissivity analysis. Two patterns are observed for oxide thickness versus temperature: below 900 °C, emissivity values are quasi-continuously increasing with oxide thickness, exhibiting an oxide layer mainly composed by TiO2, above 900 °C, emissivity values are also continuously increasing but with a different trend, due to the formation of alumina, confirmed by X-Ray Diffraction (XRD) measurements. Finally, the dependence of emissivity to temperature and oxide thickness emphasized in this paper constitutes a non-trivial mandatory input to increase the radiative heat transfer simulations codes accuracy.

This paper proposes a flexible ionization-conducted probe sensor for measuring detonation velocity produced by microcharges. Probe array structure is used to obtain multiple sets of data in finite charge length. Moreover, a flexible MEMS fabrication process based on Parylene interlayer is developed to achieve miniaturization and thin film of the probe and flexibility of the sensor. The detonation velocity measurements were performed on a booster explosive of 0.5mm×0.5mm and a primary explosive of 1mm×1mm. The experiment results suggest that an appropriate distance between two adjacent probe groups is 4mm, and the detonation velocity test system established in this paper is feasible for different microcharges. This study may lead to the development of effective methods for determining detonation velocity precisely of microcharges.

TlMeSe2 (Me: Tl, In) semiconducting compounds exhibiting chain structure have been attractive ternary materials in various technological devices. In the TlMeSe2 structure, Tl1+ is monovalent while Me3+ is trivalent ions. The present paper reports the results of spectroscopic ellipsometry measurements performed on Tl1+(Tl0.2In0.8)3+Se2 (abbreviated as Tl1.2In0.8Se2) single crystals which were grown by substituting thallium for indium. The measurements were performed for orientations of E//c and E丄c (E: electric field and c: optical axis). The analyses of ellipsometry data considering air-sample optical model presented the spectral dependencies of dielectric function, refractive index and extinction coefficient in the 1.2–5.0 eV range. Critical point energies of studied single crystal were obtained by fitting second-energy derivative spectra of dielectric function. The determined energies were compared with those of TlInSe2 to understand the effect of thallium-indium substitution in the compound. The crystal structure and atomic compositions of the constituent elements were also reported throughout the paper.

Single crystal silicon is an important material in the semiconductor industry. Slicing is the first process of silicon machining, and silicon is usually sliced by the diamond wire saw. Silicon is an anisotropic material. In slicing, properties of silicon at different positions contacting with the diamond grits on the diamond wire saw would be different. As a result, the cutting forces on the diamond grits in different positions would be different. The difference of cutting force would lead to the deviation of diamond wire saw in the direction of the wafer thickness and form surface shape deviation. The surface shape deviation would affect the amount of material removed in the subsequent process and the positioning accuracy of silicon crystal plane. In the condition that the diameter of the wafer is large or the wafer is ultra-thin, the influence of the surface shape deviation would be particularly serious. The (100), (110), (111), (112) and (120) crystal planes are studied in this paper. A diamond wire saw model considering the anisotropy of silicon is established and the sawing force is obtained. While the anisotropic properties of silicon are obtained by the coordinate transformation. The surface shape deviation of the wafer is then obtained based on the sawing force. Also, the shape of silicon the wafer is simulated. Based on the model established in this paper, the variation of the surface shape deviation with the feed angle of diamond wire saw is obtained. Experiments are carried out and the results are verified. According to the research results of this paper, certain feed angles of the diamond wire saw can be chosen to obtain the least surface shape deviation and reduce the influence of anisotropy of silicon.

The purpose of this paper is to investigate the DRAGON5 accuracy for studying a PWR pin-cell benchmark, using the ENDF/B-VIII.0 nuclear data library based on 172 energy groups, in DRAGLIB format. This paper focuses on the neutronic and burn-up analysis of the Uranium fuel using DRAGON5 transport code. The precision of the deterministic Code DRAGON5 was validated by comparing Results obtained from analysis of the UO2 pin cell high burn-up benchmark with previously published literature values. The results of a study showed good agreement. Maximum absolute difference in infinite multiplication factor between DRAGON5 and CASMO-4 is found to be 0.23% for UO2 pin cell benchmark. Furthermore, the isotopic inventories and activities have been calculated/evaluated versus the fuel burn-up (BU) time for the natural UO2 fuel, and the enriched UO2 fuel at 1.2 %.

The United States inventory of the spent nuclear fuel (SNF) is ~80,000 metric tons of heavy metal (MTHM) at the end of 2018, which contains ~131 tons of minor actinides (MAs) and ~669 tons of plutonium. This paper describes a conceptual design of an accelerator-driven subcritical (ADS) system for disposing of this SNF inventory by utilizing the 131 tons of MAs inventory and a fraction of the plutonium inventory for energy production and transmuting some long-lived fission products. An ADS system with a homogeneous subcritical fission blanket was first examined to define the main system parameters. A spallation neutron source is used to drive the fission blanket and it is generated from the interaction of a 1-GeV proton beam with a lead–bismuth eutectic (LBE) target. The fission blanket has a liquid mobile fuel using LBE as the fuel carrier. The fuel materials are dissolved, mixed, or suspended in the liquid fuel carrier. Monte Carlo simulations were performed for three fission blankets to determine the main concept parameters. The loaded amount of actinide materials in the LBE carrier is either 5, 7, or 10% of the total volume of the fission blanket, respectively. The plutonium fraction in the MAs of each fission blanket was selected so that the neutron multiplication factors of the three fission blankets are ~0.980. In addition, Monte Carlo burnup simulations using the MCB5 computer program were performed to analyze the performance of the three conceptual ADS systems. During operation, fresh fuel is fed into the fission blankets to adjust its subcriticality and to control the system power. The burnup results show that the total MA materials consumed are about 30.6, 35.3, and 37.2 tons, after operating the three fission blankets for 35 full-power years with 25-MW 1-GeV proton beam. Thus, the corresponding numbers of ADS systems to utilize the 131 tons of MA materials of the SNF inventory are 4.3, 3.7, or 3.5, respectively. ADS systems with tube bundles inserted in the fission blanket were analyzed to overcome the disadvantages of the homogeneous fission blanket concept. The liquid lead is used as the target material, the mobile fuel carrier, and the primary coolant to avoid the polonium production from bismuth. Physics and thermal–hydraulic analyses were coupled to determine the parameters of the heterogeneous fission blanket. The engineering requirements for a satisfactory performance of the HT-9 ferritic steel structure material have been realized. Two heterogeneous fission blanket concepts with the liquid lead mobile fuel inside or outside the tube bundles were considered. The heterogeneous fission blanket with the mobile fuel inside the tubes shows better performance than the fission blanket with mobile fuel outside the bundle tubes and it is presented in this paper. MCB5 and Serpent, the Monte Carlo burnup computer programs were both used to simulate the fuel burnup in the ADS concept with the mobile fuels inside the tubes for 35 full power years. The results show that five ADS systems can dispose of the total United States inventory of the spent nuclear fuel.

Chitosan (CS) is a natural and biopolymer that are suitable biomedical properties such as; biocompatibility, non-toxicity, biodegradability and bioactive polymer that’s reason with a very large application (fabrication of biomedical scaffolds, implants). Some of the biocompatible thermoplastic polymers (PLA, PEEK, PLGA, PE, PP, PMMA, PET and etc.) are most widely used in biomedical field as per their properties from last two decades. Poly-vinyl chloride (PVC) thermoplastic polymer are most widely used in medical field but there are some limitations of their uses. For enhancement of PVC thermoplastic polymers properties sometimes add some bioactive and biocompatible fillers or other bioactive thermoplastic polymers. In this review paper try to link and discussed about the possible reinforcement CS in PVC thermoplastic polymer for biomedical applications.

To clarify the anodic dissolution mechanism of Mg, the hydrogen evolution from pure Mg in acidic solutions under galvanostatic conditions were systematically measured. With increasing anodic current density, the cathodic hydrogen evolution rate decreased, and the anodic hydrogen evolution became faster while some surface area on the Mg was becoming dark under anodic polarization. Based on the surface analysis results and the generally accepted basic electrochemical equations, the evolution kinetics of hydrogen from Mg was deduced, and the most possible surface intermediate active species that could facilitate the anodic Mg dissolution and anodic hydrogen evolution were proposed. This paper further develops the model of incomplete film Mg+ dissolution, explains many reported experimental phenomena, and clarifies misunderstandings of current mechanism.

Silver nanoparticles are generally used in various products due to their distinctive and antibacterica activities. Nanosilver are used in electronics bio-sensing, clothing, cosmetics, sunscreen and medical devices but a large numbers of in vitro shows that AgNPs has toxic effects on various cultured mammalian cells. In this paper I reviewed about the toxicity effect of silver nanoparticles(AgNPs) on humans Health. In addition we studied to which content the silver ion fraction contribute the toxicity to cells. However by green formation of silver nanoparticles(AgNPs) the toxicity of silver nanoparticles can be reduced. More studies and research is required that confer AgNPs at lower toxicity only then their use would be proved useful in several industry biomedical contexts and for human health also. The ambition or goal of this review is to estimate the literature on the toxicity of silver nanoparticles. The aim of this review to inspire more studies in the field of toxicity of nanoparticles of silver or silver nanoparticles.

As a promising hydrogen storage material, the practical application of magnesium is obstructed by the stable thermodynamics and sluggish kinetics. In this paper, three kinds of NiTiO3 catalysts with different mole ratio of Ni to Ti were successfully synthesized and doped into nanocrystalline Mg to improve its hydrogen storage properties. Experimental results indicated that all the Mg-NiTiO3 composites showed prominent hydrogen storage performance. Especially, the Mg-NiTiO3/TiO2 composite could take up hydrogen at room temperature and the apparent activation energy for hydrogen absorption was dramatically decreased from 69.8 ± 1.2 (nanocrystalline Mg) kJ/mol to 34.2 ± 0.2 kJ/mol. In addition, the hydrogenated sample began to release hydrogen at about 193.2 °C and eventually desorbed 6.6 wt% H2. The desorption enthalpy of the hydrogenated Mg-NiTiO3-C was estimated to be 78.6 ± 0.8 kJ/mol, 5.3 kJ/mol lower compared to 83.9 ± 0.7 kJ/mol of nanocrystalline Mg. Besides, the sample revealed splendid cyclic stability during 20 cycles. No obvious recession occurred in the absorption and desorption kinetics and only 0.3 wt% hydrogen capacity degradation was observed. Further structural analysis demonstrates that nanosizing and catalyst doping led to a synergistic effect on the enhanced hydrogen storage performance of Mg-NiTiO3-C composite, which might serve as a reference for future design of highly effective hydrogen storage materials.

In this paper, recent results regarding rare earth element doped with chalcogenide glasses for optical gain media such as amplifiers and lasers are reviewed. Rare earth Chalcogenide glasses are formed when chalcogen elements (S, Se, Te etc.) are mixed with new additive elements (Ge, Ga, Sb, As etc.) and also with rare earth elements (Er, Dy, Pd, Pr etc.) from periodic table and prepared by melt quench technique (MQT). Rare earth element doped with chalcogenide glasses has been emerged as a suitable candidate for applications in the numeral passive and active. Among various materials, chalcogenide glasses show significant improvement in their emission properties in the optical communication range and spectroscopic properties. Finally, rare earth doped chalcogenide and optical fibers show potential for high power mid-infrared gain medium and their spectroscopic properties as well.

The appearance of high-entropy alloys (HEAs) makes it possible for a material to possess both high strength and high ductility. It is with great potential to apply HEAs under extreme conditions such as in the penetration process. In this paper, experiments of WFeNiMo HEA and tungsten heavy alloy (WHA) projectiles penetrating medium-carbon steel were conducted by using the ballistic gun and two-stage light-gas gun that can accelerate projectiles to impact velocities ranging from 1162 m/s to 2130 m/s. Depth of penetration (DOP) at elevated impact velocities of HEA and WHA projectiles were obtained firstly. Combined with the macroscopic and microscopic analysis of the residual projectiles, the transition of the penetration mode of the WFeNiMo HEA projectile was identified systemically. The experimental results indicated that the penetration mode of the HEA projectile changes from self-sharpening to mushrooming with the increase of impact velocity, while for the WHA projectile, the penetration mode is always mushrooming. The microstructure of the residual HEA projectiles showed that the phases tangle with each other and the morphology of the microstructure of the phases differs in the two penetration modes. Besides, the evolution of shear bands and fractures varies in the two modes. The evolution of the microstructure of HEAs causes the sharp-pointed nose to disappear and the HEA projectile ultimately becomes blunt as the impact velocity increases.

Biodegradable magnesium alloys have excellent properties with respect to biodegradability, biocompatibility, and biomechanics, which may indicate a possibility of its application in intestinal stents. Investigation of Mg-Zn-Y-Nd alloy's application in intestinal stents has been performed. This study aims to investigate the degradation behavior of Mg-Zn-Y-Nd alloy intestinal stents coated with poly(L-lactide)/paclitaxel in the intestinal environment and its biocompatibility with intestinal tissue. In this paper, Mg-Zn-Y-Nd alloy's corrosion properties were evaluated by the immersion test in human feces, SEM and XRD, and animal tests. In vitro results showed that when the Mg-Zn-Y-Nd alloy was immersed in human feces for two weeks, its corrosion resistance could be improved by micro arc oxidation (MAO) and poly-l-lactide (PLLA) dual coating. Additionally, this result was also confirmed in vivo experiments by rabbit model. And animal tests also demonstrated that the Mg-Zn-Y-Nd alloy with MAO/PLLA/paclitaxel dual coating drug-eluting stents could inhibit the proliferation of local intestinal tissue around the stents. However, in vivo studies illustrated that the intestinal stents gradually degraded in rabbit model within 12 days. Considering the degradation rate of the stent was faster than expected in rabbits, the support performance of the scaffold requires further improvement.

Friction self-piercing riveting (F-SPR) process based on a pip die has been invented to solve the cracking problems in riveting high-strength and low-ductility light metals, such as magnesium alloys, cast aluminum, and 7 series aluminum alloys. In this paper, in order to solve quality issues caused by the misalignment between rivet and pip-die in F-SPR, a flat-die based F-SPR process was proposed and employed to join 1.27 mm-thick AA6061-T6 to 3 mm-thick AZ31B. The results indicate that a 1.0 mm die distance is effective to avoid rivet upset and insufficient flaring. As the feed rate increases, the heat input in the whole process decreases, resulting in a larger riveting force, which in turn increases both the bottom thickness and interlock amount. Besides, solid-state bonding, including Al-Mg intermetallic compounds (IMCs), Al-Mg mechanical mixture, and Al-Fe atom interdiffusion was observed at the joint interfaces. The upper Al layer was softened, but the lower Mg layer was hardened, and both sheets exhibited a narrowed affected region with the increase of feed rate, while the rivet hardness shows no obvious change. Three fracture modes appeared accompanying the variations in lap-shear strength and energy absorption as the feed rate increased from 2 mm/s to 8 mm/s. Finally, the F-SPR process using a flat die was compared to those using a pip die and a flat bottom die to show the advantage of flat die on coping with the misalignment problem.

Clay brick masonry unit (CBMU) walls are widely used in building structures, and its damage and protection under explosion loads have been a matter of concern in the field of engineering protection. In this paper, a series of full-scale experiments of the response characteristics of 24 cm CMBU walls unreinforced and reinforced with polyurea elastomer subjected to blast loading were carried out. Through setting 5.0 kg TNT charges at different stand-off distances, the damage characteristics of masonry walls at different scaled distances were obtained. The reinforcement effect of different polyurea coating thicknesses and methods on the blast resistance performance of masonry walls under single and repeated loads were also explored. Five failure grades were summarized according to the dynamic response features of masonry walls. Based on the stress wave propagation pattern in multi-media composite structures, the internal stress distribution of masonry walls were analyzed, and the division basis of the masonry walls’ failure grades was then quantified. Combined with Scanning Electron Microscope(SEM) images, the deformation characteristics of soft and hard segments of polyurea and effects of detonation products on microstructures were revealed respectively, which provides an important reference for the design and application of polyurea in the blast resistance of clay brick masonry walls.

With increasing ballistic threat levels, there is ever more demand on developing ceramic armor designs with improved performance. This paper presents finite element simulations that investigate the performance of silicon carbide ceramic with steel 4340 backing material and titanium alloy, graphite as buffer layers when subjected to normal and oblique impacts by a tungsten alloy long rod projectile (LRP). Depth of penetration from experimental measurements is compared with simulations to confirm the validity of constitutive, failure model parameters. Titanium alloy cover plate and graphite interface weak layer laterally spread the impact shock away from the SiC tile and reduces the amplification of the stress accumulation at the front surface of the SiC tile. The dwelling time increases before it penetrates into ceramic armor. Further, using AUTODYN® numerical simulations detailed parametric study is carried out to identify the minimum areal density armor for a given ballistic limit velocity. The equivalent protection factor for the bi-layer armor is a simple function of the cosine of the angle of impact.

This paper describes the synthesis of La-doped SnO2 nanoparticles for resistive-type relative humidity sensors. The structural characterization of synthesized SnO2 nanoparticles was analyzed using X-ray Diffraction (XRD), that exhibited the formation of the tetragonal rutile structure of pristine and La-doped SnO2 nanoparticles with a decrease in crystallite size in presence of different doping levels. Further increase in doping concentration (at 5 M%) revealed the formation of the La2O3 phase due to the excess amount of lanthanum. The UV–Vis spectroscopy indicates the doping of lanthanum (La) improves the optical property of pristine SnO2. The morphological characterization demonstrates the spherical-shaped nanoparticles. The synthesized nanoparticles were tested for relative humidity (RH) sensing application over the range of 10–100% RH at room temperature. The doping of 3 M% La-doped SnO2 shows good sensitivity (95%) than pristine SnO2 nanoparticles. The fabricated 3 M% La-doped SnO2 sensor not only showed better sensitivity and linear range over 10–100%RH, but also exhibited rapid response (8sec) and recovery (13sec) time than the pristine and the others La-doped levels of SnO2 nanoparticles. This better humidity sensing response of 3 M% La-doped nanoparticles was achieved due to high carrier density and small crystallite size. This indicates 3 M% La-doped nanoparticles is a promising material for room temperature humidity sensing.

This present research paper discusses about the fabrication of metal matrix composite coating on AZ31B magnesium alloy substrate with Al, Co and TiN mixed precursor powders by gas tungsten arc (GTA) cladding process. Firstly, Co and TiN powders were mixed properly in the ratio of 1:1. Thereafter, three samples with different compositions of 20 wt% (Co + TiN)), 25 wt% (Co + TiN)), 30 wt% (Co + TiN)) and balance aluminium powder were developed by preplaced technique. The samples were heated by TIG torch at the optimized parameter as current of 110 Amp, voltage of 25 V, welding speed of 4.23 mm/s and thermal energy of 3.12 kJ/cm. After melting and solidification metallurgical bonding between coating and substrate occurs. The microstructure and chemical composition of the coated samples were analysed by field emission scanning electron microscope (FESEM) and energy dispersive spectroscopy (EDS) respectively. The micro hardness of coated samples were analysed by Vickers micro hardness testing. It was found that with increase in percentage content of Co + TiN the amount of microhardness increases. Furthermore, it was found that the value of maximum microhardness was 422 HV0.1, which was nearly seven times higher than that of the magnesium alloy substrate (64 HV0.1).

The passage of charged particles through ferroelectric medium produces localized changes in spontaneous polarization within the material. As the beam traverses the medium, it produces an electric field perpendicular to the direction of propagation of the beam. A theoretical approach is presented to estimate the electric field that is produced in the ferroelectric medium by passage of energetic electron beam and proton beam that can be probed to see the switching of ferroelectric domains. The transverse electric field produced by the 6 MeV electron beam is 183.6 MV/cm and for 25 MeV Proton beam is 14.79 MV/cm at a radial distance of 1 nm from the rectilinear path. This electric field so produced is large enough to cause the switching of ferroelectric domains. The method demonstrates a unique tool to probe the mechanism of ferroelectric domain switching along the large surface of the medium without any physical contact. This paper describes the method of theoretical estimation of transverse electric field and the ferroelectric domain switching time at and around phase transition of a known ferroelectric sample of Barium Titanate (BaTiO3) crystal.

We developed recently [A. Fert\'e, et al., J. Phys. Chem. Lett. 11, 4359 (2020)] a method to compute single site double core hole (ssDCH or K$^{-2}$) spectra. We refer to that method as NOTA+CIPSI. In the present paper this method is applied to the O K$^{-2}$ spectrum of the CO$_2$ molecule, and we use this as an example to discuss in detail its convergence properties. Using this approach, a theoretical spectra in excellent agreement with the experimental one is obtained. Thanks to a thorough interpretation of the shake-up states responsible for the main satellite peaks and with the help of a comparison with the O K$^{-2}$ spectrum of CO, we can highlight the clear signature of the two non equivalent carbon oxygen bonds in the oxygen ssDCH CO$_2$ dication., Comment: 16 pages, 7 figures, 7 tables

This paper report a new biodegradable epidermis of onion (Allium cepa) doped with low viscosity ionic liquid as novel electrolyte for EDLC application. The porous membrane used in present study was epidermis of onion (onion peel membrane) and low viscosity ionic liquid (IL) i.e. 1-ethyl 3-methyl imidazolium thiocynate. The electrical, structural, optical characterization was carried out in detail. The optical micrographs show addition in amorphosity with adding IL. Fourier transform infrared spectroscopy (FTIR) revealed the interaction between ionic liquid and membrane as well as composite nature of membrane electrolyte. Impedance spectroscopy revealed the twofold enhancement in conductivity value by doping IL. Electrical double layer supercapacitor (EDLC) has been fabricated using carbon nanotube (CNT). Cyclic voltammetry and low frequency impedance spectroscopy data further affirm the reasonable value of specific capacitance (Csp = 9.2F/g).

With the high competition in market, the increase in quality and reliability of gas sensors is highly desirable. Compatible gas sensors having high precision, high sensitivity, economical have attracted a lot of attention. For good gas sensing, research on sensing material have been broadly focused. An improvement in Nano technology and use of different materials has led to the development of efficient and effective gas sensors. The Nano- materials manifest properties that are incomparable with the granular polycrystalline counterpart. With the advancement in Micro and Nano technology, micro-sized gas sensors have been developed with great sensing performance. For detection of toxic gases various techniques are available but solid state gas sensors offer a wide spectrum of materials and their sensitivities towards various types of gases. Of all the solid state gas sensing materials, semiconductor metal oxide nanostructures are more preferable due to the stability of their oxides, high response, low cost for fabrication, response to wide range of chemicals etc. They are cost effective, reliable, and robust and have quick response time. In this paper we have studied about the semiconductor metal oxide gas sensors. The effects due to morphological structure on sensing properties are also discussed. The existing detailed literature survey on techniques and mechanisms for the nanostructures and their gas sensing ability are also involved.

Titanium and its alloys have become the ultimate choice for the next era of orthopedic implants such as Hip stem, acetabular cup, and orthopedic accessories. This critical review presents the challenges in fabrication and solutions (surface engineering) to successfully implement Ti alloys in biomedical industries successfully. A critical review on the application surface modification of Ti-alloy using thermal spray coatings has been reported. Hydroxyapatite (HA) has been used as vital biological coating-materials for load-bearing implant applications, mostly hip implants. Moreover, the research papers also present bibliometric analysis that reveals the researcher's information and their affiliation for significant contribution in the area of Ha-coatings on Ti-alloy using plasma spray techniques.