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• Microchip shows semi-mobile C. elegans respond to electric field (electrotaxis). • Electrotaxis of tail-trapped worms is towards the cathode with head. • Electrotaxis of head-trapped worms is also towards the cathode with tail. • 6-OHDA affects the electrotaxis of semi-mobile Parkinson disease (PD) model worms. • L-dopa treatment rescues both neurodegeneration and electrotaxis in PD worms. Microfluidic-based electrotaxis assay is a quantitative movement phenotyping technique for behavioral studies on Caenorhabditis (C.) elegans which is currently space-consuming and limited for cell imaging. To address these limitations and show applications in Parkinson's Disease (PD) studies, we introduce a novel microfluidic device to investigate the electrotaxis of semi-mobile C. elegans and image them immediately after the behavioral assay. The device consisted of an electrotaxis screening channel integrated with a perpendicular tapered microchannel that was used for worm tail or head trapping for electrotaxis screening and full-body immobilization for neuron imaging. Semi-mobile C. elegans with trapped tails demonstrated electrotaxis orientation towards the cathode. Interestingly, the response of head-trapped worms was also with the tail towards the cathode, implying the involvement of the mid-body to tail sensory neurons in electrotaxis. Moreover, semi-mobile C. elegans electrotaxis assay time is 3-folds shorter and 20-folds less space-consuming, compared to our freely moving assay. This makes the technique amenable to parallelization for the design of multi-worm electrotaxis and neuronal screening devices. For biological application to PD studies, we showed that human α-synuclein protein accumulation or exposure to neurotoxin 6-OHDA affected the electrotaxis phenotypes of semi-mobile worms. Moreover, L-DOPA rescued the electrotaxis of 6-OHDA exposed worms. The above behavioral effects of 6-OHDA and L-DOPA corresponded well with the degeneration of dopaminergic neurons and rescue of dopamine transmission, confirmed by on-chip fluorescent imaging. Our technique can be used for PD pathology studies and potentially for other neurobehavioral disorders modeled in C. elegans. [ABSTRACT FROM AUTHOR]

• Collision avoidance algorithm for a cable-driven parallel mechanism is suggested. • The desired trajectory is preserved while avoiding collisions between the cables. • The direct kinematics resolution considers a linear displacement of the reels. • An optimization of the linear displacement is considered in the problem resolution. Cable driven parallel mechanisms (CDPMs) have attracted much attention due to their many advantages over conventional parallel mechanisms, such as the significantly large workspace and the dynamics capacity. One of the main issues involved in designing CDPMs is avoiding cable-cable collision, especially when an operator is sharing the same workspace with the moving parts of the mechanism. This paper aims to model and simulate a reconfigurable fully constrained CDPM and solve the forward and inverse kinematics given that the attachment points on the rails move up and down in real time, unlike conventional CDPMs where the attachment points are firmly fixed on specific positions on the rails. The new idea of reconfiguration is then used to avoid interference between two cables in real time by moving one cable's attachment point on the frame to increase the shortest distance between them while keeping the trajectory of the end effector unchanged. This new approach was tested by creating a simulated intended cable interference trajectory, hence detecting and avoiding cable collision using the proposed real time reconfiguration while maintaining the end effector trajectory. [ABSTRACT FROM AUTHOR]

This experiment aimed to ascertain whether adding chitosan-oligosaccharides (COS) to the diet will affect Mandarah laying hens' productivity and reproductive efficiency. At the age of 34 weeks, 120 laying hens and 12 cocks of the Mandarah chicken strain were separated into four groups, each consisting of 30 hens and three cocks. The 1st group served as a control group, receiving only a basic diet. The 2nd, 3rd, and 4th experimental groups received 0.1, 0.2, and 0.5 g/kg of chitosan-oligosaccharides as an addition to the base diet, respectively. According to the findings of this study, the majority of the analyzed attributes differed significantly between treatment groups. Comparing the COS-treated birds to the control birds, the COS-treated birds significantly increased egg production, improved feed conversion, Haugh unit score, shell thickness, fertility, hatchability, ovary weight, and the number of yellow ovarian follicles as well as blood estradiol-17β (E2) and testosterone concentrations. Furthermore, compared to the other treated groups, introducing COS at a level of 0.1 g/kg diet resulted in the best laying rate, egg mass, and feed conversion. The highest percentage of fertility, hatchability of hatching eggs, ovary weight, number of yellow ovarian follicles, and serum E2 concentration was also found in birds fed COS at a dose of 0.2 g/kg feed. In addition, compared to the control diet, COS treatment at 0.1, 0.2, and 0.5 g/kg enhanced relative economic efficiency by 464.43, 457.41, and 352.75%, respectively. It is concluded that chitosan improves economic efficiency, reproductive performance, productivity in laying hens, and overall health when used at 0.1 g/kg diet. [ABSTRACT FROM AUTHOR]

Hot pressing represents a promising consolidation technique for ball-milled bismuth telluride alloys, yet deep investigations are needed to understand its effect on the thermoelectric properties. This paper studies the effect of hot-pressing parameters (temperature and pressure) on the thermoelectric properties of the n-type Gr-Bi2Te2.55Se0.45 nanocomposite. Ultra-high pressure, up to 1.5 GPa, is considered for the first time for consolidating Bi2(Te,Se)3 alloys. Results from this study show that increasing the temperature leads to changes in chemical composition and causes noticeable grain growth. On the contrary, increasing pressure mainly causes improvements in densification. Overall, increments in these two parameters improve the ZT values, with the temperature parameter having a higher influence. The highest ZT of 0.69 at 160 °C was obtained for the sample hot-pressed at 350 °C and 1 GPa for 5 min, which is indeed an excellent and competitive value when compared with results reported for this n-type Bi2Te2.55Se0.45 composition. [ABSTRACT FROM AUTHOR]

Unconventional treatments can provide a modification to convert ash waste into valuable materials that can be used in various applications. This study focuses on bottom ash (BA) collected from a local incineration plant and characterizes its chemical composition before and after pretreatment by coating with polymers. The toxicity-characteristic leaching procedure (TCLP) was used to identify selected heavy metal leaching after treatment with vinyl-terminated polydimethylsiloxane (PDMS) of different molecular weights. BA coatings were incorporated in two ratios, 0.5% and 1%, by milling to avoid heavy metal leaching. The results showed that all the coating batches had reduced concentrations of copper (Cu), manganese (Mn), and zinc (Zn), whereas the concentrations of chromium (Cr) and cadmium (Cd) showed higher amounts of BAV34 (0.5%) and BAV25 (1%). The treated BA with GP demonstrated percentages of reduction of 70%, 65%, 80%, 75%, 90%, and 80% for Cu, Mn, Ni, Zn, Pb, and Cd, respectively. The milling procedure reduced the particle size of the coated ash. Hydrophobicity was observed in all coating batches compared to untreated BA. The thermogravimetric analysis (TGA) results showed variations between BA and treated BA, which confirmed that PDMS caused surface modification. These features have potential significance for extending the use of coated ash as a sustainable material for construction applications. • The leachability of heavy metal was investigated by Toxicity-characteristic leaching procedures (TCLP). • Coating by PDMS, and milling methods are a potential pretreatment for BA. • Surface modification impacted the hydrophobicity and the leachability of heavy metal. • The best coated formulation was indicated with GP and BV25 (1%) coatings. [ABSTRACT FROM AUTHOR]

The development of highly efficient and durable anode materials for ethanol electro-oxidation remains a challenge. Herein, we report the synthesis of Pt 1−x−y Ir x Ni y nanocrystals via one-step procedure by ultrasonic-assisted co-reduction of the metal precursors using ascorbic acid as a mild reducing agent and pluronic F127 as a structure directing agent. The catalytic performance of this ternary catalyst towards electrochemical oxidation of ethanol was examined and compared to its mono and binary Pt counterparts (Pt, Pt 1−x Ir x , and Pt 1−y Ni y) that are synthesized by the same method. TEM analysis showed a porous nanodendritic structure for the synthesized ternary electrocatalyst with an average size of 20 ± 1 nm. The electrochemical measurements revealed an electrochemically active surface area, ECSA, of 73 m2 g−1. The as-synthesized ternary electrocatalyst showed an improved catalytic activity towards ethanol oxidation in 1 M KOH with a measured mass activity of 3.8 A mg−1 which is 1.7, 2.0, and 3.2 times higher than that of Pt 1−x Ir x , Pt 1−y Ni y , and Pt, respectively. Additionally, the Pt 1−x−y Ir x Ni y nanocrystals expressed high poisoning tolerance (j f / j b = 4.5) and high durability compared to its mono and binary counterparts. Unlabelled Image • Pt 1-x-y Ir x Ni y nanocrystals were synthesized using one-step approach at room temperature. • The as-synthesized ternary electrocatalyst expressed porous nanodendritic morphology. • The ethanol electro-oxidation performance of Pt 1-x-y Ir x Ni y towards is superior compared to mono and binary counterparts. • Ternary Pt 1-x-y Ir x Ni y nanocrystals displayed outstanding poisoning tolerance and stability. [ABSTRACT FROM AUTHOR]

Selected technological characteristics and bioactive compounds of juice pressed directly from the mash of whole Opuntia dillenii cactus fruits have been investigated. The impact of pulsed electric fields (PEF) for a non-thermal disintegration on the important juice characteristics has been evaluated in comparison to microwave heating and use of pectinases. Results showed that the cactus juice exhibited desirable technological characteristics. Besides, it also contained a high amount of phenolic compounds being the major contributors to the overall antioxidant activity of juice. HPLC-DAD/ESI-MS n measurements in the fruits’ peel and pulp showed that isorhamnetin 3- O -rutinoside was determined as the single flavonol found only in the fruit’s peel. Treating fruit mash with a moderate electric field strength increased juice yield and improved juice characteristics. Promisingly, the highest release of isorhamnetin 3- O -rutinoside from fruit’s peel into juice was maximally achieved by PEF. [ABSTRACT FROM AUTHOR]

In this work tungsten disulphide nanostructures loaded with platinum-oxide (PtO), or palladium-oxide (PdO) were grown directly onto alumina substrates. This was achieved using a combination of aerosol-assisted chemical vapour deposition (AA-CVD) method with atmospheric pressure CVD technique. At first, tungsten oxide nanowires loaded with either PtO or PdO nanoparticles were successfully co-deposited via AA-CVD followed by sulfurization at 900 °C in the next step. The morphological, structural, and chemical characteristics were investigated using FESEM, TEM, XRD, XPS and Raman spectroscopy. The results confirm the presence of PdO and PtO in the WS 2 host matrix. Gas sensing attributes of loaded and pristine WS 2 sensors were investigated, at room temperature, towards different analytes (NO 2 , NH 3 , H 2 etc.). Both pristine and metal-oxide loaded WS 2 gas sensors show remarkable responses at room temperature towards NO 2 detection. Further, the loaded sensors demonstrated stable, reproducible, ultrasensitive, and enhanced gas sensing response, with a detection limit below 25 ppb. Additionally, the effect of ambient humidity on the sensing response of both loaded and pristine sensors was investigated for NO 2 gas. The response of PtO loaded sensor considerably decreased in humid environments, while the response for pristine and PdO loaded sensors increased. However, slightly heating (at 100 °C) the sensors, suppresses the influence of humidity. Finally, the long-term stability of different sensors is investigated, and the results demonstrate high stability with repeatable results after 6 weeks of gas sensing tests. This work exploits an attractive pathway to add functionality in the transition metal dichalcogenide host matrix. • Tungsten disulphide nanostructures loaded PtO, or PdO were successfully grown by coupling AACVD and CVD methods. • The fabricated sensors were investigated thoroughly towards NO2, NH3, H2S, H2 and CO at room temperature. • Loaded sensors demonstrated ultrasensitive and enhanced NO2 gas sensing responses, with a detection limit below 25 ppb. • The fabricated sensors showed high stability with repeatable results after 6 weeks of gas sensing tests. [ABSTRACT FROM AUTHOR]

The rapid development of technology has brought about a revolution in healthcare stimulating a wide range of smart and autonomous applications in homes, clinics, surgeries and hospitals. Smart healthcare opens the opportunity for a qualitative advance in the relations between healthcare providers and end-users for the provision of healthcare such as enabling doctors to diagnose remotely while optimizing the accuracy of the diagnosis and maximizing the benefits of treatment by enabling close patient monitoring. This paper presents a comprehensive review of non-invasive vital data acquisition and the Internet of Things in healthcare informatics and thus reports the challenges in healthcare informatics and suggests future work that would lead to solutions to address the open challenges in IoT and non-invasive vital data acquisition. In particular, the conducted review has revealed that there has been a daunting challenge in the development of multi-frequency vital IoT systems, and addressing this issue will help enable the vital IoT node to be reachable by the broker in multiple area ranges. Furthermore, the utilization of multi-camera systems has proven its high potential to increase the accuracy of vital data acquisition, but the implementation of such systems has not been fully developed with unfilled gaps to be bridged. Moreover, the application of deep learning to the real-time analysis of vital data on the node/edge side will enable optimal, instant offline decision making. Finally, the synergistic integration of reliable power management and energy harvesting systems into non-invasive data acquisition has been omitted so far, and the successful implementation of such systems will lead to a smart, robust, sustainable and self-powered healthcare system. [ABSTRACT FROM AUTHOR]

This experiment investigated the influence of different synbiotic processing methods on the intestinal bacterial count, morphology and histological status of developed male Mandarah chicks. Two hundred and ten male Mandarah line chicks aged 1 d were randomized to receive one of 7 chicks. The method and dose for 1-time synbiotics administration to the day-old chicks were as follows: G1: chicks on basal diet received no treatment (control); G2: 0.25 mL synbiotics sprayed; G3: 0.50 mL synbiotics sprayed; G4: 0.25 mL of synbiotics are added to drinking water; G5: 0.50 mL of synbiotics are added to drinking water; G6: 0.25 mL of synbiotics dripped into the mouth; and G7: 0.50 mL of synbiotics dripped into mouth drops. Lactic acid bacteria (LAB) were significantly increased (P<0.0001) compared to the control group and other treated groups and had the maximum values after the use of synbiotics via drinking water (0.25 or 0.50 mL). Furthermore, when comparing the treated birds (G4, G5) with the control birds, the Escherichia coli concentration in the drinking water containing synbiotics was significantly lower. In addition, treated chickens at (G7) showed a higher duodenum, ileum villus height (VH) , and VH. - Ileum crypt depth (CD) ratio compared to other groups. In addition, birds treated with 0.50 mL of synbiotics in drinking water (G5) performed better in duodenum, ileum, CD and VH. - CD ratio than the other groups. Meanwhile, intestinal tract length and visceral pH did not differ significantly between groups. It can be concluded that the use of 0.25 mL of synbiotics in drinking water can improve the overall health of birds. [ABSTRACT FROM AUTHOR]

Abstract: Cryogenic high energy ball milling was used to synthesize nanocrystalline Cu and Cu99.5Zr0.5 alloys by mechanical alloying and consolidation by hot pressing at 550°C temperature. The grain size stability of nanocrystalline Cu is improved by the Zr addition. Microstructural characterization using X-ray diffraction and transmission electron microscopy provided evidence for the formation of a Cu–Zr alloy solid solution with nanocrystalline size after hot pressing. The alloy exhibited a higher hardness (3.31GPa), and shear strength (550MPa) than nano-crystalline pure Cu however, the electrical resistivity is increased in the alloy. [Copyright &y& Elsevier]

Mechanical attrition—the mechanical alloying or milling of powders—is a very versatile and potent method of obtaining nanocrystalline or ultrafine grain structures with enhanced properties. This article presents three examples of enhanced properties obtained by materials in which the grain size has been reduced to the nanoscale or ultrafine scale by ball milling and consolidation of powders. Very high strength/hardness—the highest hardness yet reported for crystalline Mg alloys—for a ball milled Mg97Y2Zn1 alloy is due in part to the nanocrystalline grain structure, along with nanoscale precipitates. A ternary Cu-base alloy with a low stacking fault energy was found to have both high strength and good ductility in a nanocrystalline material synthesized by the in situ ball milling consolidation method. This is another example that shows nanocrystalline materials need not be brittle. It is shown that bulk thermoelectric materials with superior properties can be produced by the ball milling and consolidation of powders to provide an ultrafine grain structure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanofiller dimensionality governs the thermoelectric properties of Bi 2 Te 3 composites. • The ZT enhancement of these composites is mostly preeminent to 2D nanofillers. • Superior thermoelectric properties are attained using doped Bi 2 Te 3 matrixes. This review paper summarizes and discusses the effect of nanosized fillers on bismuth telluride nanocomposites for thermoelectric applications. Classified into various dimensions based on electron confinement in space, the nanofiller effect on the figure-of-merit value is studied. By combining experimental data with theoretical models, the mechanisms for enhancing the thermoelectric properties were proposed. The outcomes of this review paper suggest that doped bismuth telluride composites (doped with selenium for n-type or antinomy for p-type) offer better thermoelectric properties compared to undoped composites. Moreover, improvements in undoped bismuth telluride composites are exclusive for the n-type only. The figure-of-merit value for bismuth telluride composites is less than two, where the 2D nanofillers show optimum ZT improvements. Nevertheless, the inconsistency of reported data in the thermoelectric area is a problem that must be addressed to have more control over the precision of the reported results for a better understanding of the concepts in this field. [ABSTRACT FROM AUTHOR]

• Different milling times affected the structural defects in graphene and its distribution in the n-type Bi 2 Te 2.7 Se 0.3 matrix. • Long milling time induced higher levels of structural defects in graphene and reduced the composite's electrical conductivity • Ten minutes of mechanical milling was the optimum time to enhance the thermoelectric properties of the composite. • The improved ZT is attributed to the low level of structural defects and reduced agglomeration of graphene in the composite. This study examines the effects of the structural integrity of graphene on the thermoelectric properties of n-type bismuth telluride alloy. Graphene/Bi 2 Te 2.7 Se 0.3 composites were prepared via mechanical alloying and spark plasma sintering techniques. Different graphene concentrations (0.05 and 0.5 wt%) and addition times (20 hrs, 10 mins, and 1 min) were considered. The thermoelectric properties were measured, and the results showed that the milling time affects graphene structure as well as its agglomeration. It is revealed that the optimum time to add the two-dimensional filler is during the last phase of mechanical milling as it will preserve graphene's structure and boost the electrical conductivity. It is also shown that as the milling time of graphene increases, the Seebeck coefficient improves. Even though an increase in the thermal conductivity is expected due to the high electrical conductivity, a clear reduction in the lattice thermal conductivity part was obtained due to the increased scattering at the new interfaces. The figure-of-merit for the optimum sample with 0.05 wt% graphene added in the last 10 mins of milling had an improvement of 19% at room temperature reaching a value of 0.5, and 25% at 160 °C achieving a final value of 0.81. [ABSTRACT FROM AUTHOR]

• Tin Selenide/Graphene nanoplatelets (SnSe/GNPs) nanocomposite is synthesized by ball milling and hot pressing. • Milling time has a significant effect on enhancing the distribution of graphene within the matrix. • Homogeneous distribution of graphene enable decoupling the Seebeck coefficient and the electrical conductivity. • Homogeneously distributed graphene provides a continuous path for carriers to move, hence enhancing the carrier mobility. • Optimum milling time has a significant effect on enhancing the power factor of SnSe/GNPs nanocomposite. [Display omitted] Tin selenide graphene nanocomposites (SnSe/GNPs) were fabricated with high-energy ball milling and hot pressing by varying the milling time of graphene. The effect of ball milling time on the graphene integrity and the dispersion homogeneity was investigated and the consequential variation in electrical properties of SnSe/GNPs were analyzed. The evolution of graphene sheets during milling as well as the crystal structure of SnSe/GNPs nanocomposites were systematically studied by X-ray diffraction, Raman analysis, scanning electron microscopy, and transmission electron microscopy. It has been proven that graphene was able to keep its crystallinity at short milling times, but it exhibits agglomeration and poor dispersion within the matrix. However, long milling time has a significant effect on increasing the disorders on graphene structure while it provides well dispersion of graphene. The calculated power factor increases with the addition of graphene and with increasing graphene milling time. The increased power factor is attributed to the homogeneous distribution of graphene, which results in a significant increase in electrical conductivity. At 773 K, the lowest power factor value was reported for the 1-min graphene-milled sample, whereas a 40% enhancement was reported for the 2-h graphene-milled sample. Across a wide temperature range (298–720 K), the 12-h graphene-milled sample shows the best performance owing to the simultaneous increase of electrical conductivity and Seebeck coefficient. These findings indicate the positive effect of milling time on the distribution of graphene, which in turn enables graphene to form a continuous net for carriers to move. This study could provide a greater understanding of the control factors of the mechanical milling process for preparing SnSe/GNPs nanocomposites in order to take full advantage of graphene's extraordinary properties by improving its distribution within the tin-selenide- based composite. [ABSTRACT FROM AUTHOR]

Metal-graphene nanocomposites and plasmonic metal nanoparticles are two nanoscience fields of a rapidly growing interest due to their potential in advanced applications. In this study, we combine both fields by synthesizing plasmonic aluminum-lithium-graphene nanosheets (Al–Li-GNSs) with anisotropic morphologies using a simple ball-milling technique. Structural analysis using SEM and TEM revealed that the Al–Li-GNSs nanoparticles are single-crystals with a hexagonal platelet-like morphology of a ∼300–500 nm diagonal and a ∼60 nm thickness. Electron diffraction analysis indicated that the as-milled platelets have an FCC structure with (111) top and bottom facets and revealed the presence of 1/3(422) and 1/3(220) forbidden reflections. UV–Vis spectroscopy of the hexagonal Al-based nanoplatelets was found to exhibit plasmonic resonance absorption bands in the UV region at a wavelength of 214 nm and 345 nm. In this report, we confirm the feasibility of building epitaxial plasmonic metal-graphene systems inside bulk metal-graphene composites using a simple milling process. [Display omitted] [ABSTRACT FROM AUTHOR]

This study aimed to determine the influence of dietary mannan-oligosaccharides (MOS) on the immune system, hematological traits, blood biochemical parameters, and histological state of laying hens. At 34 wk of age, The Mandarah chicken strain's 120 laying hens and 12 cocks were divided into 4 groups, each with 30 hens and 3 cocks. The first group performed as a control group, which nourished on a basal diet. The second, third, and fourth experimental groups received 0.1, 0.2, and 0.5 g/kg of MOS and a base diet, respectively. Birds obtained MOS at numerous doses significantly (P ˂ 0.05) raised serum levels of immunoglobulin Y (IgY), immunoglobulin M (IgM), and avian influenza (AI) antibodies compared to control birds. Furthermore, adding MOS at a level of 0.1 g/kg diet significantly improved the immune response of the control group. Additionally, compared to the control group, treated birds with MOS at various dosages did not significantly enhance hematological parameters such as red blood cells (RBCs), white blood cells (WBCs), hemoglobin, and hematocrit. Compared to control birds, birds fed MOS at all levels exhibited considerably lower serum cholesterol, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) values. Also, compared to other treated birds, MOS-treated birds displayed improved histological examination of the small intestine, isthmus, and testis compared to the control group, particularly in birds fed MOS at 0.1 and 0.2 g/kg diet. It could be concluded that using MOS at 0.1 or 2 g/kg diet can successfully improve the physiological performance and overall health of laying hens. [ABSTRACT FROM AUTHOR]

This experiment aimed to examine the effect of chitosan-oligosaccharides (COS) supplementation in laying hens' diets affected their immune response, hematological characteristics, blood biochemical parameters, and histological status. At the age of 34 wk, 200 laying hens and 20 cocks of the Mandarah chicken strain were allotted into four groups, each consisting of 50 hens and five cocks. The first group acted as a control group, fed on a basal diet. The second, third, and fourth experimental groups each received 0.1, 0.2, and 0.5 g/kg of COS in addition to a base diet. Birds received COS at various dosages had significantly (P ˂ 0.05) increased serum concentration of immunoglobulins, avian influenza, and Newcastle disease antibodies compared with the control birds. Moreover, adding COS at level 0.2 g/kg diet insignificantly enhanced immune response than the rest of the treatment groups. Also, treated birds with COS at different levels had insignificantly improved hematological parameters such as red blood cells, white blood cells, hemoglobin and hematocrit compared to the control group. Birds fed COS at all levels had significantly decreased serum cholesterol, triglycerides, Ca++ and alanine aminotransferase concentrations compared with control birds. In addition, compared to the control group, chitosan-treated birds showed enhanced histological examination of the small intestine, isthmus, and testis, notably in birds given COS at 0.1 g/kg diet compared to other treated birds. Cocks fed COS at all levels improved testicular tissues and increased the number and diameter of seminiferous tubules compared with control birds Morphological examination of the ileum showed increased villi number, height, and crypt depth. It is possible to conclude that laying hens' physiological performance and general health can be effectively improved by using chitosan at 0.1 or 2 g/kg diet levels enhanced immune response. [ABSTRACT FROM AUTHOR]

Numerous efforts have been made to understand and enhance the thermoelectric properties of bismuth telluride alloys. However, limited studies have been reported to investigate the corrosion behavior of these alloys and their suitability for industrial applications. This paper examines the corrosion behavior of three different bismuth telluride alloys prepared by induction melting: pristine Bi 2 Te 3 , n-type Bi 2 Te 2.55 Se 0.45 , and p-type Bi 0.6 Sb 1.4 Te 3. The electrochemical response of the samples is tested in 3.5 wt% NaCl solution at room temperature. Potentiodynamic polarization curves (Tafel plots) revealed that the n-type sample formed a passive layer compared to the pristine and the p-type samples, which showed pitting corrosion. The different trends observed in the samples were related to their evolved microstructures, where fingerprint-like features in the pristine and the p-type samples showed high susceptibility to pitting corrosion. In contrast, a unique needle-like microstructure of the n-type samples acted as nucleation sites for passive layer formation causing higher corrosion resistance in this sample. • Electrochemical response of undoped and doped Bi 2 Te 3 produced by induction melting was studied in 3.5 wt% NaCl solution. • The electrochemical response significantly depends on the microstructural features of the Bi 2 Te 3 alloys. • Fingerprint-like features in undoped Bi 2 Te 3 and Sb-doped alloys showed high susceptibility to pitting corrosion. • The needle-like microstructure of the Se-doped Bi 2 Te 3 acted as nucleation sites for passive layer formation, causing high corrosion resistance. [ABSTRACT FROM AUTHOR]

Interest in nanocrystalline (nc) aluminum-lithium (Al-Li) alloys is motivated by the demand for lightweight and high-performance materials for light-weighting applications and superior fuel consumption. Nonetheless, nc metals, including Al are thermally unstable, which hinders their technological applications. In this study, we explore the effect of combining dilute amounts of strontium (1.0 at% Sr) and graphene nanoplatelets (1.0 wt% GNPs) to investigate the thermal stability of a nc Al-Li alloy. Ball milling was used to prepare four samples: Al-Li, Al-Li-Sr, Al-Li-GNPs, and Al-Li-Sr-GNPs, to systematically investigate the role of each added element. Isothermal annealing was conducted at different temperatures to investigate the thermal stability. Despite maintaining a nanometric grain size and high hardness of 70 nm and 1.1 GPa, respectively, after annealing at 773 K for 1 h, the Al-Li-Sr-GNPs sample suffered the most significant grain growth and the highest drop in hardness when compared to the Al-Li-Sr and Al-Li-GNPs samples. Microstructural investigations suggested that competing effects resulting from the spontaneous reaction of both Sr and GNPs with Al at higher temperatures resulted in a declining thermal stability efficiency. The formation and distribution of the rod-like Al 4 C 3 phase at the grain boundaries stood in the way of proper Sr diffusion after annealing and caused the agglomeration of the Al 4 Sr phase. [Display omitted] • The thermal stability of nc Al-Li alloy was studied through Sr and GNPs additions. • The Al 4 Sr and Al 4 C 3 formed at the GBs contributed to the improved thermal stability. • Rod-like Al 4 C 3 formed at the grain boundaries prevented the proper Sr segregation. • Agglomeration of the Al 4 Sr resulted in a declined thermal stability efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] We combined descriptor-based analytical models for stiffness-matrix and elastic-moduli with mean-field methods to accelerate assessment of technologically useful properties of high-entropy alloys, such as strength and ductility. Model training for elastic properties uses Sure-Independence Screening (SIS) and Sparsifying Operator (SO) method yielding an optimal analytical model, constructed with meaningful atomic features to predict target properties. Computationally inexpensive analytical descriptors were trained using a database of elastic properties determined from density functional theory for binary and ternary subsets of Nb-Mo-Ta-W-V refractory alloys. The optimal Elastic-SISSO models, extracted from an exponentially large feature space, give an extremely accurate prediction of target properties, similar to or better than other models, with some verified from existing experiments. We also show that electronegativity variance and elastic-moduli can directly predict trends in ductility and yield strength of refractory HEAs, and reveals promising alloy concentration regions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Nanostructured diamond die pressed onto Si and Ge samples to replicate 500nm pitch features. [•] Fast nanocoining procedure was successful in replicating features at 1600 features per second. [•] Nanofeatures were replicated without local fracture. [•] Forces were measured during indentation for both materials. [•] Micro-Raman measurements provided evidence of pressure induced phase transformation. [ABSTRACT FROM AUTHOR]

[Display omitted] High Entropy Alloys (HEAs) are an increasingly dominant alloy design paradigm. The premise of entropic stabilization of single-phase alloys has motivated much of the research on HEAs. Chemical complexity may indeed help stabilize single alloy phases relative to other lower-entropy competing solid phases. Paradoxically, this complexity may de-stabilize these alloys against the liquid phase, potentially limiting the application space of HEAs at elevated temperatures. In this work, we carry out a comprehensive investigation of the phase stability in the fcc CoCrFeMnNiV-Al HEA space using a state of the art CALPHAD database. By using modern visualization techniques and statistical analysis we examine the trade-off between chemical complexity and stability against the liquid state and identify a potentially difficult to overcome barrier for development of high temperature alloys, at least within the conventional fcc HEA space. Limited experimental data seem to be consistent with this analysis. [ABSTRACT FROM AUTHOR]

Stacking Fault Energy (SFE) is an intrinsic alloy property that governs much of the plastic deformation mechanisms observed in fcc alloys. While SFE has been recognized for many years as a key intrinsic mechanical property, its inference via experimental observations or prediction using, for example, computationally intensive first-principles methods is challenging. This difficulty precludes the explicit use of SFE as an alloy design parameter. In this work, we combine DFT calculations (with necessary configurational averaging), machine-learning (ML) and physics-based models to predict the SFE in the fcc CoCrFeMnNiV-Al high-entropy alloy space. The best-performing ML model is capable of accurately predicting the SFE of arbitrary compositions within this 7-element system. This efficient model along with a recently developed model to estimate intrinsic strength of fcc HEAs is used to explore the strength–SFE Pareto front, predicting new-candidate alloys with particularly interesting mechanical behavior. [Display omitted] [ABSTRACT FROM AUTHOR]

In the present investigation, aluminum metal matrix composites (AMMs) reinforced with aluminum nitride (AlN) nanoparticulates at different volumetric ratios of (0, 0.5, 1, 1.5, and 2 vol.%) were manufactured via a microwave-assisted powder metallurgy technique. The morphological, physical, mechanical, and electrochemical properties of the produced billets were examined to reflect the impact of the successive addition of AlN into the aluminum (Al) matrix. The morphological analysis revealed the high crystalline patterns of the formation of the Al-AlN composites. The microstructural analysis confirmed the presence of the elemental constituents of Al and AlN particles in the fabricated composites, showing an enhanced degree of agglomeration in conjunction with the additional amount of AlN. Positive behavior exhibited by the micro- and nanohardness was noticeable in the Al-AlN composites, especially at the ultimate concentration of AlN in the Al matrix of a 2 vol.%, where it reached 669.4 ± 28.1 MPa and 659.1 ± 11 MPa compared to the pure Al metal at 441.2 ± 20 MPa and 437.5 ± 11 MPa, respectively. A declining trend in the compressive strength was recorded in the reinforced Al samples. The corrosion resistance of the AlN-reinforced Al metal matrix was estimated at 3.5 wt.% NaCl using electrochemical impedance spectroscopy and potentiodynamic polarization. The results reveal that the inclusion of 2.0 vol.%AlN led to the lowest corrosion rate.

This study investigates the simultaneous decoration of vertically aligned molybdenum disulfide nanostructure (VA-MoS 2 ) with Ag nanoparticles (NPs) and nitrogen functionalization. Nitrogen functionalization was achieved through physical vapor deposition (PVD) DC-magnetron sputtering using nitrogen as a reactive gas, aiming to induce p-type behavior in MoS 2 . The utilization of reactive sputtering resulted in the growth of three-dimensional silver structures on the surface of MoS 2 , promoting the formation of silver nanoparticles. A comprehensive characterization was conducted to assess surface modifications and analyze chemical and structural changes. X-ray photoelectron spectroscopy (XPS) showed the presence of silver on the MoS 2 surface. Scanning electron microscopy (SEM) confirmed successful decoration with silver nanoparticles, showing that deposition time affects the size and distribution of the silver on the MoS 2 surface.