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Nanotechnology has gained momentum in recent years in the field of drug delivery, including nanomedicine and nano-delivery systems. Several applications such as biological agents, chemotherapeutic agents and immunotherapeutic agents are used for the treatment of a number of diseases. This review compiles an updated summary on recent developments in this emerging field of nanomedicines and nanotechnology-based drug delivery systems. The study of nanostructured drug delivery systems helps to understand the efficient transport and controlled release of drugs to the diseased tissues of living organisms. This has stimulated the authors to highlight recent advances in smart nanocarriers composed of biopolymeric nanoparticles such as liposomes, dendrimers, and hydrogels. This review also highlights some critical issues in the design of nanocarrier systems for biomedical applications.

NiCr–Cr3C2 coatings are widely used for high temperature and tribological applications due to their high hardness, oxidation, and wear resistance properties. In the present investigation, an attempt is made to further enhance the hardness and adhesion strength of NiCr–Cr3C2 coatings by reinforcing them with multi-walled carbon nanotubes. The carbon nanotubes (3–7 wt%) with varying weight percentages were mixed with NiCr–Cr3C2 using a planetary ball rolling mill and sprayed on SA213 T12 (T12 alloy steel tube) using a high-velocity oxy-fuel spraying process. The microstructures of mixed powder, coating cross-section, and fractured coating surface were characterized using a scanning electron microscope while X-ray diffraction was used for phase identification in the fractured coating surface. The coated samples were subjected to microhardness and adhesion strength tests according to ASTM E384 and ASTM D4541-09 standards. Out of all coatings, NiCr–Cr3C2/7% carbon nanotube composite coating showed the lowest porosity of 1.17%, highest microhardness, and adhesion strength of 563.8 HV and 55.8 MPa, respectively. A fracture analysis after a pull-off adhesion test revealed adhesion failure for NiCr–Cr3C2 coating and combined adhesion/cohesion failure for NiCr–Cr3C2/7% carbon nanotube composite coating.

Thermoset resin-based composite materials are widely used in the aerospace industry, mainly due to their high stiffness-to-weight and strength-to-weight ratios. A major issue with the use of thermoset resins in fiber composites is the process-induced residual stresses that are formed from resin chemical shrinkage during the curing process. These residual stresses within the composite material ultimately result in reduced durability and residual deformations of the final product. Polybenzoxazine (PBZ) polymer resins have demonstrated near-zero volumetric shrinkage during the curing process. Although the low shrinkage of PBZ is promising in terms of reduced process-induced residual stresses, little is known about the physical causes. In this work, Molecular Dynamics (MD) simulations are performed with a reactive force field to predict physical properties (gelation point, evolution of network, mass density, volumetric shrinkage) and mechanical properties (Bulk modulus, Shear modulus, Young's modulus, Poisson's ratio, Yield strength) as a function of crosslinking density. The MD modeling procedure is validated herein using experimental measurements of the modeled PBZ resin. The results of this study are used to provide a physical understanding of the zero-shrinkage phenomenon of PBZ. This information is also a critical input to future process modeling efforts for PBZ composites.

The design and synthesis of a highly sensitive and exceptionally selective surface-enhanced Raman scattering (SERS) substrate with an excellent reusable property are of significant interest because...

In the present attempt, order-to-disorder transition of oxygen vacancies and their correlation with ion transport mechanism in moderately (at.15%) and heavily (at. 30%) doped (Gd and Sm) ceria systems are explored by using a high-temperature X-ray diffraction (HT-XRD) and Raman and dielectrics spectroscopy techniques. Oxygen vacancies disordering is integrated with polarization phenomenon. The density of disordered oxygen vacancies and conducting ions is revealed by the imaginary part of electric modulus (M”). Relaxations of conducting ions are confirmed by M” as a function of frequency at various temperatures, and peak height M” curve is used to quantify the density of disorder states. HT-XRD study exhibits detectable mismatch in lattice parameter during expansion and contraction at particular temperature. The mismatch parameter is correlated to kinetic process induced in the samples caused by long-range disordering of oxygen vacancies. HT-Raman spectra confirm temperature-dependent disordering of oxygen vacancies. The energy of disordering of oxygen vacancies at grain and grain boundaries region is calculated from the slope of the log (fmax) versus 1000/T plots, where fmax is the frequency associated with M”max. Disordering energy at the grain boundary is more than grain in almost all systems. The temperature correspond to the order–disorder transition of oxygen vacancies is closely associated with oxy-ion conductivity. Arrhenius plot of conductivity depicts the kink in the slope of the conductivity curves for all ceria systems for the temperature ranges from 400 to 500 °C. The activation energy of conductivity in the temperature region of ordered oxygen vacancies is more than disordered oxygen vacancies. Conductivity maxima are associated with the density of disordered oxygen vacancies.

Tellurite glass is a model material having superior features for several applications. It can be considered as a potential host matrix for different oxides, and this paper aims to study the effects of TeO2/B2O3 substitution on synthesis, physical, optical and radiation shielding properties of ZnO–Li2O-GeO2-Bi2O3 glasses produced by melt quenching technique. The physical and optical features of the fabricated glasses were experimentally investigated by determining pivotal parameters such as density, XRD, tellurium ion concentration (Ni), linear refractive index (no), polaron radius (rp) and inter nuclear distance (ri). Moreover, the relative radiation deposition within the glasses was assessed via the attenuation coefficients (e.g. MAC), specific gamma ray constant (ᴦ), total stopping power (TSP), neutron cross sections, and dose rate (D). Our results suggest that both TeO2 and B2O3 additives have a significant effect on the fundamental properties of the ZnO–Li2O-GeO2-Bi2O3 glasses. It also found that the lower thicknesses of the present glasses are required to provide the same level of shielding than ordinary, ilmenite, steel scrap, hematic-serpentine, ilmenite-limonite and basalt-magnetite concretes, RS253-G18 and RS360 glass shields. Therefore, presently investigated glasses are promising photon shields in different technological applications of gamma- and x-rays.

The aim of the study was to investigate the hybrid robust optimization planning approach in intensity-modulated proton therapy (IMPT) of craniospinal irradiation (CSI).Five IMPT-based adult CSI plans in supine position were created using Raystation treatment planning system (TPS) modelled for Proteus plus proton therapy system. A hybrid planning strategy was implemented, where clinical target volume was robustly optimized (RB) for set up uncertainties and planning target volume was optimized for target coverage using minimax algorithm in the TPS. Beam angle selection, optimization, and dose calculation approach were carefully performed to ensure optimum organ at risk (OAR) sparing, even with potential setup and range errors. The complementary dose gradients in junctions were generated using spot assignment and RB technique. Dosimetric outcomes in both nominal plan and the 16 error scenarios (±3 mm setup and 3.5% range) were analyzed using standard dose volume histogram.This planning approach resulted in a homogeneous dose distribution in the target volume of CSI, including the junction regions, by explicitly reducing number of robust optimization scenarios. The proposed technique was also able to achieve excellent coverage to cribriform plate with lower lens doses and minimal dose to other OARs. Target and OAR doses in the nominal plans as well as in the worst case scenarios with setup and range errors were able to meet the predefined clinical goal.This proposed planning technique is efficient, robust against the uncertainties. It could be adopted in other proton therapy centers.

Food preservation technologies are currently facing challenges in prolonging the shelf life of perishable food products. The uses of edible films and coatings developed from food biopolymers have advanced significantly during the last few years. Edible packaging is consumable and made from food-grade biopolymers, including lipids, proteins, and polysaccharides from plants, animals, and marine life or food processing by-products. Here we review natural polymer and bioactive compounds integrated into edible films and coatings, and their effects on food quality attributes. We present preparation techniques for edible films and coatings, and properties such as antimicrobial, antioxidant, physical, and sensory. Recent trends on film composition, nanotechnology in edible films, and safety concerns are reviewed.

The novel Cu2P2O7 and Cu2P2O7@PPy electrode materials have been synthesized by a simple hydrothermal method. The fabricated electrode materials were characterized by XRD, FESEM, BET and XPS techniques to evaluate the structural, morphological, textural and chemical composition of the samples. Monoclinic structure with novel blade and honeycomb-like morphologies of Cu2P2O7@PPy composite sample was identified by XRD and FESEM studies. The BET surface area and BJH pore size of the Cu2P2O7@PPy composite sample were calculated to be 117.2 m2/g and 18.5 nm, which is higher than that of the Cu2P2O7 sample (83.5 m2g−1 and 34.2 nm). The electrochemical results suggest that the fabricated electrode exhibits high specific capcitance of 765 Fg−1at 1 Ag−1 current density. The capacitance retention of composite electrode delivers 99.6% after 6000 cycles. The fabricated ASC cell has a huge capacitance of 115 Fg−1 and capacitive retention of 92 % after 6000 cycles at a low current density of 1 Ag−1. In addition, the cell has a 39.8 WhKg−1 high energy density and a current density of 3582 Wkg−1at 1 Ag−1.

A thin film of cobalt selenide is deposited on the fluorescence tin oxide-coated glass surface material using a simple chemical growth technique. In this article, we report on the study of photoelectrochemical characteristics (PEC), including current–voltage, capacitance–voltage characteristics, photovoltaic power output, and spectral response in dark and light conditions. For the above parameter study, we prepared using cobalt selenide and carbon electrode (using polysulfide as electrolyte), the battery configuration is expressed as n-CoSe/NaOH (1 M) + Na2S (1 M) + S (1 M)/C (graphite). The performance of the cobalt selenide thin film material the resulted values of respective series (RS) and shunt (RSh) resistance 2.280 kΩ and 1.224 Ω, respectively. The efficiency and fill factor of these PEC cells were found to be 0.899 and 28.72%. The junction ideality value are found to be (nD) is 0.69 in the dark and 2.72 in the light (nL). The M–S plots are constructed using C−2 against applied bias voltage (with respect to SCE) for CoSe PEC cell. The positive slope of the M–S plot confirms n-type conductivity of the CoSe films. The carrier density values of the samples obtained from the M–S plots varied from 3.48 × 1014 cm−3.

Obtaining high-strength aluminium alloy welded joints considering the effect of tool geometry and process parameters still needs attention. In this study, AA7075-T651 aluminium alloy plates were jo...

Lacidipine is a calcium channel blocker used in treatment of cardiac arrhythmia. Several methods had been reported for the estimation of lacidipine from bulk and formulations. Here in this an attempt is made to summarize the different methods used along with their specifications. Every method reported for the analysis had its own advantages over the other methods. As per the industrial scalability HPLC is the most useful and effective method for the estimation of Lacidipine from bulk and formulations.

An active antioxidant film was fabricated by using polyvinyl alcohol (PVA) and corn starch (ST) and incorporated with and 3, 5, 10, and 20% (v/v) coconut shell extract (CSE) and sepiolite clay (SP) for the first time. The microstructure and physical properties of prepared films were characterized and examined. The addition of sepiolite clay to PVA improved the elongation break 15.57 to 69.24%, and water vapor permeability increased with the addition of CSE. In addition to CSE to films, the antioxidant activity properties of the films were enhanced up to 80%. Further, increasing the amount of CSE slightly affected the color of the active films. The thermal properties of films were enhanced with the addition of CSE and SP. The dispersion of SP in the PVA matrix was affected by an increase in CSE concentration in the PVA matrix. Remarkably, PVA-ST film-based sachets successfully improved the oxidative stability of packaged soybean oil. Our results suggest PVA-ST film containing CSE and sepiolite clay can be utilized as a novel antioxidant packaging material in the food processing industry.

Aim of research paper is to compare and briefly describe about the advantage and limitations of solid storage structure by using Staad Pro Structural software. Solid storage structures are considered as special structures as its design is based on the properties of materials stored. The pressure exerted by the stored material on the side of a bin varies with the processes and arrangements of filling and emptying operations. Due to this variation, it is extremely difficult to analyze the pressure exerted on the walls of the bins. In our research work, we are designing the RCC solid storage structure located in all seismic zones with the help of structural software Staad Pro. The design concept include, all dimensions of structural component based on trial and error method, using Equivalent lateral force method in term of Comparison of different models of concrete solid storage structure for earthquake such as nodal displacement, stress and vertical or horizontal pressure on walls etc. for volume of 180 m3. All the designs have been based on the recommendations of I.S 4995 -1974 (part 1&2) and I.S 456 – 2000 codes, Based on these designs, that dimension of solid storage structures shows least amount of concrete and steel. Main objective of our research work is to compare of different models of concrete solid storage structure for earthquake in terms of nodal displacement, stress and vertical or horizontal pressure on walls etc.

Nanoparticles of Mn-substituted NiCuZn ferrite with an elemental composition Ni0.5−xMnxCu0.2Zn0.3Fe2O4 was synthesized by the sol–gel auto-combustion technique. Structural and electrical characteristics were analyzed by the X-ray diffraction (XRD), scanning electron microscopy, dielectric, permeability, and impedance spectroscopy measurements. Rietveld-refined XRD patterns reveal single phase with cubic symmetry of the prepared samples. The dielectric parameters such as dielectric constant and loss have been examined at room temperature and are explained in the light of Maxwell–Wagner interfacial polarization. Complex permeability analysis has been used to separate grain and grain boundary in the studied samples. Saturation magnetization, complex permeability, and dielectric constant of NiCuZn ferrite increased up to a certain level of Mn substitution. The results obtained could be of interest for the research of compositionally altered NiCuZn soft ferrites for ferrite-core application.

Super duplex stainless steel (UNS S32750) butt joints were prepared using ER2594 and ER2595 electrodes by shielded metal arc welding (SMAW) process. The heat input used during welding was in the range of 0.75–0.81 kJ/mm. Microstructure and texture across the weldments were investigated using optical microscope, scanning electron microscope, and electron backscattered diffraction. The solidification mode in the fusion zone (FZ) was found to be ferritic, and the microstructure mainly consisted of Widmanstatten austenite (WA), grain boundary austenite (GBA), and inter-granular austenite (IGA). The base metal (BM) had ~ 50% ferrite and 50% austenite. The ferrite proportion changed significantly in FZ and heat-affected zone (HAZ) after welding. Austenite in the BM showed strong Brass ({110} ), Cu ({112} ), Goss ({110} ), and S ({123} ) components, while ferrite showed strong α (RD// ) and γ (ND// ) fibres. The texture of ferrite was stronger than that of austenite. The austenite and ferrite in the FZ (cap pass) obeyed Kurdjumov–Sachs (K–S) orientation relationship. Further, the hardness of ER2595 weldments was found to be higher than that of ER2594 weldments.

Simple and time efficient hydrothermal method was employed to obtain phase pure anatase TiO2 and Co2+-TiO2 nanoparticles (NPs) as an efficient visible light active photocatalyst. The phase purity, morphology, optical property, and compositions were confirmed by various characterization techniques. The XRD analysis confirms the polycrystalline nature for Co2+-TiO2 photocatalyst. Raman peaks at 398, 516.89 and 640 cm−1 affirmed anatase Co2+-TiO2 NPs and XPS analysis reveals substitution of Ti4+ with Co2+ ions in TiO2 NPs. The 1.61 wt.% Co2+-TiO2 NPs has bandgap value of 2.95 eV which specifies the efficiency of material for the absorption of visible light. The obtained TiO2 and Co2+-TiO2 materials were explored for photocatalytic degradation of MG under UV, visible and direct sunlight. The removal of MG was confirmed using COD analysis. The obtained visible light active (1.61 wt.%) Co2+-TiO2 showed 82% removal of MG under direct sunlight.

In the present work, experimental investigation on single-phase liquid flow in straight and zigzag microchannels is performed. The objectives are to investigate experimentally, the effect of influe...

When hydrogen isotopes are present in stoichiometric ratio of 2:1 with oxygen in inert gas such as helium, catalytic combustion is the most promising option to reduce the concentration of hydrogen isotopes and to minimize the associated safety hazards. This is the case, when deuterium and oxygen is formed during radiolysis of heavy water in moderator circuit of Pressurized Heavy Water Reactors (PHWR) and mixed with helium in the cover gas system. In order to design the catalytic reactor for recombination of deuterium and oxygen, the data on catalytic combustion kinetics under the similar process conditions are essential. However, the catalytic combustion data is generally reported for combustion of hydrogen in air, where oxygen is available in excess. The studies on the kinetics of catalytic combustion of deuterium where oxygen is present in stoichiometric ratio of 2:1 in an inert gas medium such as helium, is very scarce. In the present study, the multi-step reaction mechanism of catalytic combustion of hydrogen in presence of platinum catalyst is analyzed for the present process conditions. Based on the analysis, a simple rate expression is proposed for the present process conditions of catalytic combustion of deuterium. Further, 0.5% platinum catalyst is prepared on a stainless steel Dixon ring support with an objective to achieve better heat transfer characteristics and lesser reduction in the catalytic activity due to water adsorption. The kinetic data is generated using a differential packed bed reactor operating in a closed loop. The experiments were conducted at different temperatures using a stoichiometric mixture of deuterium and oxygen in helium. The rate constant for the above proposed model is estimated based on the experimental data at different temperatures. Further, the activation energy and frequency factor are determined and the activation energy for the present catalyst is found to be on the lower side in comparison to literature data.

In the present study, organically modified Montmorillonite clay with polar moiety, the Cloisite 30B, is used for preparation of Hydroxyl terminated polybutadiene (HTPB)-clay nanocomposites (HCN) by dispersion of nanoclay in polymer matrix under high shear mixing. The nanocomposites thus prepared are evaluated in composite propellants as inhibitor material for their functional utility. Several inhibition formulations containing 5 wt%-15 wt% of nanoclay, with or without the conventional filler Sb2O3, were prepared. All these formulations were evaluated for their physical, mechanical, thermal, and ablative properties. Ablation rate and density of the compositions containing Cloisite 30B is around 23% and 5% lower respectively in comparison of the base composition. Strain capability of these compositions is twofold higher than that of base composition. These compositions have also been evaluated for their smoke generation tendency by measuring infra red (IR) attenuation in the wavelength range 1.3 μm–5.6 μm and 8 μm–13 μm and thereby compared with the base composition. The corresponding results confirmed that the compositions containing Cloisite 30B as filler have much lower IR attenuation than compositions with conventional filler, Sb2O3. Replacement of 5% Sb2O3 by nanoclay showed 8% reduction in IR attenuation rate which further reduced to 16% on replacement of 15% of Sb2O3. Interfacial bonding of HCN based inhibitors is also comparable or even better than conventional inhibitors. Precisely, the nanoclay composites with Cloisite 30B as filler exhibit all desirable properties of an inhibitor.

Recently, many studies trended to develop new glass systems to serve for various radiation applications. In this article, we report on the radiation attenuation and shielding performance of the Er/Cd/Li/Gd/Si glass system in the chemical form of 50SiO2·30Li2O·(19 − x)CdO·1Gd2O3·xEr2O3 (here, 0 ≤ x ≥ 2.5 mol%). The shielding performance (LAC, MAC, MFP, EAC, HVL, EBF, EABF, and FNRC) is investigated by using the Monte Carlo method (via Geant4 simulations) and theoretical calculations (via Phy-X approach). The obtained results indicate that the Er2O3 addition has a significant influence on the attenuation performance of the present glasses. We also found that the maximum (minimum) value of MAC is obtained at photon energy of 15 keV (10 meV) with the corresponding value of 20.537 (0.028), 22.525 (0.0283), 24.44 (0.0287), 26.286 (0.0290), and 28.067 (0.0293) cm2/g for SLGC-E1, SLGC-E2, SLGC-E3, SLGC-E4, and SLGC-E5 respectively. This rivals the performance of commercial glass shields (RS-253), concretes (ordinary and barite), and recently developed and studied glass (TBZP10 glass). It can be concluded that the SLGC-E5 glassy material has promising attenuation properties to use for the radiation shielding applications.

Materials with magneto-electric (ME) properties are of great importance because of their demand in electronic industries. Three dimensional nano-particles of the ME-composites having the general formula (1-x)CoCr0.3Fe1.7O4(CCFO)+(x)BaTiO3(BTO) (x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) were obtained by comprising the piezoelectric-BTO and piezomagnetic-CCFO phases. The individual phases of CCFO and BTO were synthesized separately by ultrasonic irradiation assisted sonochemical and sol-gel routs. X-ray diffraction patterns (XRD) confirmed the well-crystalline nature of both the phases. BTO and CCFO phases were under tensile strain as confirmed by the variation in lattice constants with varying proportion of BTO and CCFO. An energy-dispersive X-ray spectroscopy spectrum confirmed the phase purity of the samples and stoichiometric concentration of elements. Magnetic properties were investigated by M − H loop measurements and dielectric properties by using RF impedance analyzer. Dielectric constant increased with the increasing percentage of BTO. The maximum value of ME coefficient (24.7 mV/cm⋅Oe) is observed for the 60%CCFO+40%BTO sample. The obtained results were discussed in the light of grain size, strain and the basic properties of the individual phases. The prepared materials can be applicable in electronic devices where high magneto-electric coefficient is desirable.

Introduction: The quality control parameters of in-house-produced 90Y-Acetate from high-level liquid waste (HLLW) using supported liquid membrane (SLM) technology were validated and compared with t...

Background: Tuberculosis (TB) continues to be among the leading causes of high mortality among developing countries. Though a seemingly effective treatment regimen against TB is in place, there has been no significant improvement in the therapeutic rates. This is primarily owing to the high drug doses, their associated side-effects, and prolonged treatment regimen. Discontinuation of therapy due to the severe side effects of the drugs results in the progression of the infection to the more severe drug-resistant TB. Objectives: Reformulation of the current existing anti TB drugs into more efficient dosage forms could be an ideal way out. Nanoformulations have been known to mitigate the side effects of toxic, high-dose drugs. Hence, the current research work involves the formulation of Isoniazid (INH; a first-line anti TB molecule) loaded chitosan nanoparticles for pulmonary administration. Methods: INH loaded chitosan nanoparticles were prepared by ionic gelation method using an anionic crosslinker. Drug-excipient compatibility was evaluated using DSC and FT-IR. The formulation was optimized on the principles of Quality-by-Design using a full factorial design. Results: The obtained nanoparticles were spherical in shape having an average size of 620±10.97 nm and zeta potential +16.87±0.79 mV. Solid-state characterization revealed partial encapsulation and amorphization of INH into the nanoparticulate system. In vitro release study confirmed an extended release of INH from the system. In vitro cell line-based safety and efficacy studies revealed satisfactory results. Conclusion: The developed nanosystem is thus an efficient approach for antitubercular therapy.

The levels of hydrogen peroxide ($${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 ) in human blood is of great relevance as it has emerged as an important signalling molecule in a variety of disease states. Fast and reliable measurement of $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 levels in the blood, however, continues to remain a challenge. Herein we report an automated method employing a microfluidic device for direct and rapid measurement of $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 in human blood based on laser-induced fluorescence measurement. Our study delineates the critical factors that affect measurement accuracy—we found blood cells and soluble proteins significantly alter the native $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 levels in the time interval between sample withdrawal and detection. We show that separation of blood cells and subsequent dilution of the plasma with a buffer at a ratio of 1:6 inhibits the above effect, leading to reliable measurements. We demonstrate rapid measurement of $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 in plasma in the concentration range of 0–49 µM, offering a limit of detection of 0.05 µM, a sensitivity of 0.60 µM−1, and detection time of 15 min; the device is amenable to the real-time measurement of $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 in the patient’s blood. Using the linear correlation obtained with known quantities of $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 , the endogenous $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 concentration in the blood of healthy individuals is found to be in the range of 0.8–6 µM. The availability of this device at the point of care will have relevance in understanding the role of $${\mathrm{H}}_{2}{\mathrm{O}}_{2}$$ H 2 O 2 in health and disease.

Six different lithium bismuth boro-tungstate glasses with chemical composition 20Li2O-(20-x)Bi2O3-xWO3-60B2O3 (x = 0, 1, 2, 3, 4 and 5 mol%) were produced by the quenching method. Then, the glasses were investigated by means of their optical, mechanical, chemical durability and gamma ray shielding properties. Measured values of density and ultrasonic velocities were used to determine the elastic properties of the glasses. The optical band gap determined using the absorbance spectrum fitting (ASF) model was found to decrease under Bi2O3/WO3 substitution. The presence of BO3, BO4, BiO6, and WO4 structural groups in the glasses was confirmed by Fourier transform infrared spectroscopy (FTIR). The dissolution rate in the glass 20Li2O–15Bi2O3–5WO3–60B2O3 (LBWB5) was found to be 10 times lower than 20Li2O-20Bi2O3– 60B2O3. Mass attenuation coefficients (MAC) values of the produced glasses were determined using the MCNPX Monte Carlo code and Phy-X/PSD program. The photon attenuation parameters such as half value layer (HVL), mean free path (MFP), effective atomic number (Zeff), exposure buildup factor (EBF) and energy absorption buildup factor (EABF) were also studied. The obtained results showed that Bi2O3/WO3 substitution has a direct impact on the photon attenuation abilities of produced glasses. More specifically, HVL values increased from 0.252 × 10−2 cm for LBWB0 glass to 0.275 × 10−2 cm for LBWB5 glass. However, different trends were observed for the photon buildup factors for the produced glasses. It can be concluded that the produced glasses have promising structural, optical, and photon attenuation properties to be used for gamma shielding applications.

The growing interest in metal–organic frameworks (MOFs) in both industrial and scientific circles has increased in the last twenty years, owing to their crystallinity, structural versatility, and controlled porosity. In this study, we present three novel MOFs obtained from the 1, 3, 5-tris (1H-benzo[d]imidazole-2-yl) benzene (TIBM) organic linker. The formed TIBM crystal powders were characterized by scanning electron microscopy (SEM) to estimate the morphology of the particles, powder X-ray diffraction (XRD) to confirm the crystal structure, Brunauer–Emmett–Teller (BET) method for structural analysis, and thermogravimetric measurements to examine the thermal stability. The TIBM-Cu MOF showed excellent CO2 (3.60 mmol/g) adsorption capacity at 1 bar and 298 K, because of the open Cu site, compared to TIBM-Cr (1.6 mmol/g) and TIBM-Al (2.1 mmol/g). Additionally, due to the high porosity (0.3–1.5 nm), TIBM-Cu MOF showed a considerable CO2/N2 selectivity (53) compared to TIBM-Al (35) and TIBM-Cr (10).

The thermo-acoustic engine is a device that operates on the temperature difference created across the regenerator mesh through hot and cold heat exchangers which produce the oscillations. Computati...

Transition metal oxides have promising candidates for supercapacitors application owing to its excellent theoretical capacitance, eco-friendly and good redox reaction feature. In this work, Nano-knotnet type cobalt oxide as an electrode material has been synthesized by a cost-effective and simple chemical bath deposition (CBD) method for supercapacitors application. The structural and morphological studies of these electrode materials were evaluated by using X-ray diffraction (XRD) and scanning electron microscopy (SEM) respectively. XRD studies showed that the cobalt oxide thin films were well-crystallized, pure, and face-centered cubic phases with average crystallite size 29.64 nm. The electrochemical behaviour of the cobalt oxide electrodes was characterized by using cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD) in 1 M NaOH aqueous electrolyte. GCD exhibited the maximum specific capacitance 322 F g−1 at a current density of 1 mA cm−2 with 84.16% retention of the specific capacitance value after 10 mA cm−2 current density. The CV and GCD measurements demonstrated binderless cobalt oxide is a promising electrode for supercapacitors application.

Semiconducting iron disilicide, β-FeSi2, has its application in thermoelectric generators using p-type and n-type semiconducting β-FeSi2. It is useful for energy conversion (waste heat energy to electrical energy) in the temperature range between 200 and 900 °C. The peritectoid and eutectoid reaction responsible in the formation of β-FeSi2 phase are very sluggish. This research work focuses on shortening of sintering period and thus conserving energy required for complete transformation of various phases to β-FeSi2. Total time required for the synthesis along with the sintering cycle is relatively less (about 20 h) than the other processes (other process durations varying from 37 h to 504 h) studied earlier. An innovative sintering cycle was developed to achieve nearly complete β-FeSi2 phase formation. p-type and n-type semiconducting β-FeSi2 were characterized for thermoelectric properties.

High strength, excellent corrosion resistance, and low density are the main properties that make titanium attractive for a variety of applications such as the production of airframes, engine components, steam turbine blades, superconductors, missiles, etc. Machining of titanium alloy by conventional machines causes the problems such as chipping and premature tool failure, deflections of the work-piece, increases the temperature at the tool-work piece interface, etc. Hence under such circumstances, nonconventional Die sink Electrical Discharge Machining (EDM) process can be alternative to overcome such problems. The primary aim of this paper is to investigate the effects of process parameters (factors) on material removal rate (MRR) in the EDM process. The process parameters considered for this investigation are current (C), voltage (V), pulse on time (Ton), and pulse off time (Toff) for EDM machining of titanium (grade-2) alloy with copper as an electrode material. The experiments were designed with the Taguchi method, orthogonal array L9. The maximum MRR obtained was 0.073 mm3/min with the voltage of 40 V, current of 8A, pulse on at 60 µs, and pulse off at 9 µs respectively. While the secondary aim of this research is to investigate the effect of process parameters on fatigue strength of titanium (grade-2) alloy. During fatigue test it was observed, fatigue strength decreases with an increase in current and pulse on time.

Continuous-drive rotary friction welding was performed to join cylindrical specimens of carbon steel (EN24) and nickel-based superalloy (IN718), and the microstructures of three distinct weld zones—the weld interface (WI)/thermo-mechanically affected zone (TMAZ), the heat-affected zone (HAZ), and the base metal—were examined. The joint was observed to be free of defects but featured uneven flash formation. Electron backscatter diffraction (EBSD) analysis showed substantial changes in high-angle grain boundaries, low-angle grain boundaries, and twin boundaries in the TMAZ and HAZ. Moreover, significant refinement in grain size (2–5 μm) was observed at the WI/TMAZ with reference to the base metal. The possible causes of these are discussed. The microhardness profile across the welded joint shows variation in hardness. The changes in hardness are ascribed to grain refinement, phase transformation, and the dissolution of strengthening precipitates. The tensile test results reveal that a joint efficiency of 100% can be achieved using this method.

Electrical discharge machining (EDM) has emerged as one of the most preferred options for high precision machining of very hard materials. Complex contours and intricate slots are produced in a variety of parts by this approach. Considerable research has been dedicated to several aspects of EDM. This work concentrated on analysis of the effect of EDM processes parameters on performance measures such as material removal rate (MRR), tool wear rate (TWR) and surface roughness. In the present study experiments were designed using response surface methodology. Moreover the analysis of variance was performed for MRR, TWR and surface roughness, along with the empirical models which shows the R2 value as 86.79%, 72.80% and 83.47% respectively.

From the last two decades the application of Friction Stir Welding (FSW) process is increased in industry due to its advantages such as ecofriendly and improved mechanical properties over the metal inert gas welding and tungsten inert gas welding. In FSW joint is fabricated by the heat generated using rotating, non-consumable tool, whereas the material remains in solid state. In the present work, the mechanical behavior of Aluminum 7075-T651 alloy (AA7075-T651) FSW joints were investigated in terms of surface roughness, ultimate tensile strength (UTS), and microhardness. Investigations were carried out by varying the welding processes parameters, namely the tool rotation at 1000, 1400, and 2000 rpm, and at two levels of welding speed of 20 and 28 mm/min. FSW experiments were performed under dry conditions using a tool having conical pin geometry. Experimental investigations showed a higher value of UTS for FSW joints at tool rotation of 1400 rpm and welding speed of 20 mm/min. the higher value of microhardness and lowest surface roughness at weld bead was observed at lower tool rotation of 1000 rpm. This study suggests further works on the mechanical behavior of high strength AA7075-T651 FSW joint considering the effect of tool geometry and hybrid welding techniques.

Understanding the concept of light–matter interaction in organic–inorganic nanostructures such as graphene and metal-halide perovskites has been explored to realize photonic and optoelectronic devi...

To address the challenges of capacity fading and poor electronic conductivity of hard carbons as anode in Li-ion batteries (LIBs), we report here the catalytic graphitization of resorcinol–formaldehyde xerogel (RFX)-derived hard carbon via a single-step synthesis by incorporating two transition metal catalysts (Co and Ni) with different loadings (5 and 10%) at a modest temperature of 1100 °C. Loading of both the catalysts affects the extent of graphitization and other physiochemical properties that have a direct influence on the anodic performance of as graphitized RFX-derived hard carbon. A 10% Ni catalyst in RFX-derived carbon induces the highest degree of graphitization of 81.4% along with partial amorphous carbon and nickel phases. This improved crystallinity was conducive enough to facilitate rapid electron and Li-ion transfer while the amorphous carbon phase contributed to higher specific capacity, resulting in overall best anodic performance as ever reported for RFX-derived carbon. A specific capacity of 578 mAh/g obtained after 210 cycles at 0.2 C with coulombic efficiency greater than 99% confirms the potential of graphitized RFX-derived carbon as an anode for high-performance LIBs.

Analysis of transient thermoelastic temperature distribution of a thin circular plate and its thermal deflection under uniform internal heat generation is investigated. The upper and lower surfaces...

We investigate, in this analysis, the entropy generation characteristics associated with the transport of nanofluid in a microfluidic channel under the combined influences of applied pressure gradient and electrical forcing. In our study, the nanofluid is subjected to an asymmetric cooling at the channel walls, while the conductive transport of heat through the channel walls is also taken into account. We show that the underlying thermo-electro-hydrodynamics of nanofluids in the channel lead to entropy generation, attributed to the irreversibilities associated with heat transfer, viscous dissipation, and Joule heating effects. We establish that a non-trivial interplay among these irreversibilities gives rise to an optimum value of the geometrical parameter, viz. the channel wall thickness ( $$ \delta $$ ), and the thermophysical parameters, viz. the thermal conductivity of the wall $$ (\gamma ) $$ , Biot number (Bi), and the modified Peclet number ( $$ \overline{\text{Pe}} $$ ), leading to a minimum entropy generation rate of the system. Also, we unveil through this study that changes in the electroosmotic parameter $$ \bar{\kappa } $$ (representative of the EDL thickness) or the composition of the fluid ( $$ \phi $$ , the volume fraction of nanoparticles agglomerates) non trivially alter the optimum values of these parameters. Inferences drawn from this analysis may have consequences in the optimum design of thermal systems/devices, typically used for thermal management in micro-heat exchangers, micro-reactors, and micro heat pipes.

New highly sensitive optically stimulated luminescent phosphors with NaCl moiety and dopants Ca,Cu,P/Mg,Cu,P are developed. These phosphors show very high optically stimulated luminescence (OSL) sensitivity. The dose response for NaCl:Ca,Cu,P is linear up to 1.2 Gy and for NaCl:Mg,Cu,P is slightly sub linear from 0.2 Gy. These phosphors show 30% fading during first 4 and later signal gets stabilised with no further signal loss. These sensitive phosphors will find applications in radiation dosimetry using OSL.

Boron-based nanostructures are considered as alternative hydrogen storage material due to its large surface area, lightweight and chemical stability. In this work, the hydrogen storage capacity and structural evolution of titanium (Ti) atoms-decorated B40 fullerene are investigated using first-principles calculations. Our result shows that Ti prefers to absorb on the outside surface of the hexagonal and heptagonal cavities of B40 ring. The average binding energy (Ebinding) for 6 Ti atoms-decorated B40 structure is calculated as 5.71 eV. The interatomic distance between two neighbor Ti atoms (5.13–5.54 A) is larger than that of Ti2 dimer (~ 2.0 A) to prevent the aggregation of Ti atoms as well as Tin cluster formation. The average adsorption energies (Eadsorption) for (Ti–nH2)6B40 (n = 2–6) structures, within a range of 0.29–0.33 eV, prove that the structures are between chemisorbed and physisorbed states (0.2–0.6 eV). We have achieved a maximum gravimetric density (H2 wt%) of 9.3 wt% exceeding the 5.5 wt% goal set by the Department of Energy, USA, by the year 2020. In addition, ab initio molecular dynamics calculations have confirmed that the (Ti–6H2)6B40 structure is stable for the hydrogen adsorption under near-ambient temperature.

This work demonstrates the effect of different shapes and positions of a wavy flag vortex generator on the heat transfer in a rectangular channel using Computational Fluid Dynamics (CFD) analysis. ...