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The desiccant wheel based air conditioning systems are superior over conventional vapour compression systems in terms of the efficiency and power consumption. Researchers are consistently focusing on the various aspects of the desiccant wheel such as the architecture of the wheel, effect of operating parameters on the performance of the wheel and the overall configuration of air-conditioning systems. For the simulations of the air-conditioning systems it is essential to have an accurately performing model of the desiccant wheel. Thus, for solving this purpose, the radial basis neural network is applied to forecast the performance of a desiccant wheel data. The input parameters are the inlet process air humidity, temperature, regeneration temperature, number of rotations per hour of the desiccant wheel and the ratio of the volume flow rates of the process air and the regeneration air. The output parameters are the temperature and humidity of the process air outlet stream. The model is able to predict the original data within ± 5% accuracy and the r-square value is obtained to be 0.9963. A parametric study presenting the variations of the process air outlet temperature and humidity with respect to the various input parameters is also included in the article.

Quinoline Schiff bases are notified for their extensive pharmacological applications which paved way for the continuous exploration of their properties by the chemists of various fields. The theoretical exploration of organic compounds finds new dimensions in the recent advances of science intend us to study the nonlinear optical behaviour of Schiff Bases. In this context, four series of substituted hydrazinoquinoline Schiff bases 1–4 [ 4-methyl-2-salicylidenehydrazinoquinoline (1), 4,6-dimethyl-2-salicylidene hydrazine quinoline (2), 6-chloro-4-methyl-2salicylidenehydrazinoquinoline (3), 4-methyl-6-methoxy-2-salicylidene hydrazine quinoline (4)] were synthesised and characterised by IR and 1H NMR spectral studies. The DFT studies of the synthesised compounds viz., Frontier Molecular Orbital analysis and first hyperpolarisabilty were carried out by using B3LYP functional 6-31G (d,p) basis level. From the DFT results, the first hyperpolarisability suggest that the studied compounds have good non-linear properties. The global reactivity descriptors value indicates that the synthesised compounds are hard with greater kinetic stability. Having lower band gap energy of 4.1 eV–3.73 eV and a low lying LUMO, the synthesised compounds might be a excellent NLO candidate and also act as superconductors, and may have prospective used in both technological as well as pharmaceutical related applications.

Titanium alloys, especially Ti–6Al–4V, were reported as a promising biomaterial featuring excellent corrosion resistance and good biocompatibility, but it lacks anti-infection capacity and osseointegration. In this work, we aimed to improve the bio-functions and corrosion resistance of AT-Ti-6Al–4V by applying cerium incorporated hydroxyapatite using a spin coater. The triple layer of Ce-HAP coatings was systematically accumulated using different speeds such as 2000, 3000 and 4000 RPM, which were sintered for 2 h at 500 °C. XRD and SEM-EDS characterize the developed Ce-HAP coatings to confirm the phase formation and surface morphology. The Colony Forming Unit confirms that Ce-HAP coatings exhibited significant inhibition efficiency towards the pathogens. In vitro bioactivity study evaluated in SBF indicates excellent apatite layer formation on Ce-HAP coatings. The cell viability studies using MG-63 cells showed good cell proliferation and attachments on a coated implant. The electrochemical properties of coatings were analysed by EIS and the result displayed pronounced anti-corrosion property. This study suggests that the cerium incorporated HAP promotes bioactivity with rapid osteointegration and presented higher corrosion resistance that makes it essential for the desired biomedical applications.

Cubic phase of MgO nanoparticles were prepared by microwave-assisted combustion synthesis and investigated for the removal of toxic dyes like Congo Red (CR) and Trypan blue (TB). The crystallite size of the MgO nanoparticle was calculated to be 18 nm from XRD pattern. The sample was further characterized by FTIR, TGA and FESEM techniques. The dyes were subjected to prototypical batch adsorption process, including investigation of different parameters like MgO dosage, dye concentration, solution pH, agitation speed and temperature. It was found that, 0.2 g of MgO NPs showed maximum removal efficiency for both the dyes (more than 98%), having 25 ppm of dye concentration at an acidic pH (3–4). The maximum loading capacity of MgO NPs was obtained to be 136 mg/g and 132 mg/g for CR and TB, respectively. Different thermodynamic parameters like ΔG0, ΔH0 and ΔS0 were measured. The negative ΔH0 and the positive ΔS0 values for both the dyes correspond to an exothermic process and an increase in randomness of the adsorbent and dye. The isotherm analysis exhibited that the Freundlich model fits better to the experimental equilibrium data, suggesting heterogeneous surface of the nanoparticles. Whereas, the kinetic data revealed a pseudo 2nd order rate for adsorption process.

Semiconducting nanowires with modulated structures are potential candidates for application in nanoelectronics and photonics devices and are crucial for the fundamental understanding of electron tr...

In recent years, photocatalysis and photoelectrocatalysis (PEC) have emerged as efficient strategies for facing the energy crisis and environmental pollution. In this regard, the very suitable and exciting material, graphitic carbon nitride (g-C3N4), has drawn spectacular attention because of its fascinating physicochemical properties. However, its practical application in the field of photocatalysis and PEC is still a bottleneck due to its narrow solar energy absorption range, low surface area, which provides less active sites, low electronic conductivity due to deficient CN donor density, poor electron–hole separation efficiency, insufficient redox potentials, and difficulty in the formation of thin films due to its poor dissolution in common solvents. To optimize the redox potential and provide effective spatial charge separation, Z scheme systems are being fabricated by imitating the natural photosynthesis process. In this review, the historical development of g-C3N4-based Z scheme systems is summarized along with their construction, synthesis, and various photocatalytic and PEC applications. g-C3N4-based Z scheme systems, such as the redox mediator solution-phase Z scheme, solid-state Z scheme, and direct Z scheme, and their characterization methods have been discussed briefly. Also, the methodology for the detection of Z scheme charge transfer processes has been explored. Lastly, conclusions and various future perspectives regarding the challenges in the construction and progress of the Z scheme photocatalytic systems are presented.

The photosensitivity of amorphous chalcogenide thin films brings out light-induced changes in the nonlinear and linear optical parameters upon sub-bandgap and bandgap laser irradiation. The present work reports the in situ laser irradiated changes in the optical properties of As50Se40Sb10 thin films. The thermally evaporated film showed an exponential decrease in optical bandgap and increase in Urbach energy. The decay rate of the bandgap was 6.24 min and growth rate of Urbach energy was 6.67 min respectively. The dynamics of photo-induced changes were observed from the changes in linear refractive index and its dependent parameters such as 3rd order nonlinear susceptibility, nonlinear refractive index, dispersion and dielectric parameters. The conversion of heteropolar to homopolar bonds induced the photodarkening mechanism that changed the dispersion parameters. The decrease in Ed and Eo reduced the oscillator strength along with the zero-frequency dielectric constant. The optical and electrical conductivity changed significantly with time. The changes were saturated with time which brings stability in the film properties that is useful for various optical applications. However, no structural and compositional changes upon laser irradiation were noticed from the X-ray diffraction and EDX studies respectively. The surface homogeneity was checked from the FESEM picture.

Recently, the development of cathode materials for Na-ion batteries has gained much attention due to the abundance, low cost, and easy availability of resources. Apart from the usual metal oxides, multi-electron redox materials grabbed attention due to their high energy density and practical capacity with long cycle life. Polyoxometalates (POMs) are inorganic clusters of higher valent metals, and act as electron sponges with multi-electron redox properties. Herein we report a Keggin-type polyoxometalate [PMo10V2O40]5− with Na+ and H+ counter cations as a cathode material for Na-ion batteries. Further the formation of POM is evidenced by PXRD, FT-IR, flame photometry and XPS studies. In Na-POM, Na+ ions in the intercluster cavities provide a better pathway and easy diffusion during the charge/discharge process, and contribute to better electrochemical properties than H-POM. The DFT studies further explore the detailed mechanistic pathway of Na+ ions around the clusters in the normal and super-reduced states. Na-POM enables better cycling stability and capacity retention with a specific discharge capacity of 123 mA h g−1 at 0.1C rate at room temperature.

In this research work, rice husk ash has been used as an admixture and the strength properties have been studied. The influence of 15% rice husk ash on strength properties has been compared with normal M30 concrete. The water cement ratio has been kept constant as 0.45. Strength tests like compressive strength, split tensile strength, flexure strength has been carried out at 28 days for normal concrete and 15% rice husk ash replaced concrete mix. For practical application of rice husk ash, reinforced beams were cast with normal concrete and rice husk ash. Both the beams were checked for load deflection. From strength tests, rice husk ash mix gave good compressive strength, split tensile strength and flexure strength values. Test on reinforced beam indicated that rice husk ash beam gave higher ultimate load value compared to normal M30 concrete beam.

As the civilization is evolving and rapid growing modernization many technical advancements has been made, which resulted in depletion of natural resources. One of the main natural construction materials is river sand, the demand for the stand increasing day-by-day. To meet the desired needs at economical ways partial usage of coir pith may be used. The outer fibre, which is taken out from the dried coconut husk is named as coir pith. These fibres are commonly discarded as an agricultural waste product. Dumping of huge quantity of coir pith in fertile or any good quality land creates numerous health problems and these lands get disturbed both physically and chemically due to its less deterioration in soil. The major properties of coir pith are an excellent moisture retention material even after drying. Enhancing internal curing maintains uniform temperature and retained all over the process of concrete to reduce or completely rid of certain crack problems like thermal shrinkage. The process of maintaining the moisture content inside the concrete for a particular period gives or enhance mechanical strength and thus it was names as curing period of concrete. This concrete possesses greater physical resiliency that withstands compression better, resulting in greater compressive strength, also 100% degradable, organic and a renewable resource and also making it economical. This paper describes various methods adopted to partially replace coir pith to fine aggregate and suggest some of the methods for utilizing coir pith in construction industry. Experimental analysis to find the physical and strength properties of coir pith are done. Comparatively treated coir pith gives better result than untreated coir pith on the basis of strength and bonding property with concrete.

The nanoscale memristor device SPICE modeling is significant for memristive circuits and neuromorphic system design applications. In this paper, a novel modified piece-wise linear (PWL) window function proposed for the nonlinear property of the memristor SPICE model. The PWL window function used here can address the shortcoming of the parabola and Heaviside- step function based typical window functions proposed in the literature, those are established by symmetrical functions. However, in most of the typical window functions, the monotonically increasing and the asymmetrical functions have not been addressed. Also, using this PWL-window function based memristor model, a binary-weighted memristor-based artificial synaptic circuit has been designed. The performance of the device model demonstrated by the efficiency of designed artificial synapse sensitivity to the external input signal.

Phosphorus, sulfur, and boron doped graphitic carbon nitride were successfully synthesized by solid-state calcination of melamine, as precursor of g-C3N4 and ammonium dihydrogen phosphate [NH4(H2PO4)], thiourea (CH4N2S), and boric acid (H3BO3) as dopant. The as synthesized materials were further subjected to chemical exfoliation using hydrochloric acid as exfoliating agent. The different physicochemical properties of the synthesized materials were well characterized by means of Powder X-ray diffraction (PXRD), UV–Visible diffuse reflectance absorption spectra (UV-DRS), photoluminescence spectra (PL), and electrochemical measurement. Boron doping into the bulk CN lattice enhance the absorption of light, electron-hole separation as revealed from absorption and PL emission spectra. From the photocurrent and impedance spectra it is clear that boron doping not only enhances the photocurrent value but also decreases the charge transfer resistance of the parent material. All synthesised materials were tested for photocatalytic hydrogen evolution reaction, out of which CNB shows highest rate of hydrogen generation (18.2 μmolh−1) which is around three times more than that of g-C3N4.

Four mononuclear cobalt (II) complexes of substituted hydrazino quinoline Schiff bases 1(a–d) were synthesised and characterized by UV, IR, NMR and TGA studies. The geometry of cobalt complexes 1(a–d) unambiguously attested as distorted octahedral’ and the ligand was coordinated through NNO donor fashion of tridentate nature. Structure of the proposed complexes were optimized using Density Functional theory (DFT) with Gaussian 09/ Gauss view software. Mulliken charges, global softness and electrophilicity index were derived for the optimized structure and the energy of highest occupied orbital (HOMO) and lowest unoccupied orbital (LUMO) and energy gap were calculated. The photophysical properties of the synthesised complexes were analyzed by UV–Visible and photoluminescence spectral studies, the results revealed that the emission bands centered in the range of 445–455 nm with higher luminescence intensity and relatively large Stoke’s shift observed (198 nm–215 nm) in the absorption and emission shoed a promising novel material towards OLED’S.

Amorphous Li3PS4 (LPS) solid-state electrolytes are promising for energy-dense lithium metal batteries. LPS glass, synthesized from a 3 : 1 mol ratio of Li2S and P2S5, has high ionic conductivity and can be synthesized by ball milling or solution processing. Ball milling has been attractive because it provides the easiest route to access amorphous LPS with a conductivity of 3.5 × 10−4 S cm−1 (20 °C). However, achieving the complete reaction of precursors via ball milling can be difficult, and most literature reports use X-ray diffraction (XRD) or Raman spectroscopy to confirm sample purity, both of which have limitations. Furthermore, the effect of residual precursors on ionic conductivity and lithium metal cycling is unknown. In this work, we illustrate the importance of multimodal characterization to determine LPS phase and chemical purity. To determine the residual Li2S content in LPS, we show that (1) XRD and 31P solid state nuclear magnetic resonance (ssNMR) are insufficient and (2) Raman loses sensitivity at concentrations below 12 mol% Li2S. Most importantly, we show that 7Li ssNMR is highly sensitive. Using 7Li ssNMR, we investigate the effect of ball milling parameters and develop a robust and highly reproducible procedure for pure LPS synthesis. We find that as the residual Li2S precursor content increases, LPS conductivity decreases and lithium metal batteries exhibit higher overpotentials and poor cycle life. Our work reveals the importance of multimodal characterization techniques for amorphous solid-state electrolyte characterization and will enable better synthetic strategies for highly conductive electrolytes for efficient energy-dense solid-state lithium metal batteries.

In this present article, zinc oxide nanoparticles (NPs) have been synthesized by a greener approach using Acacia concinna fruit extract via sol–gel technique. These biosynthesized ZnO NPs were characterized by XRD, SEM, FTIR, BET and HRTEM techniques. The XRD pattern revealed the samples are crystalline and having hexagonal ZnO phase with wurzite type structure. The morphology of zinc oxide nanoparticles were analysed by SEM, which suggested that the particles are in agglomerated form and porous in nature. The adsorption of Congo red dye by using these ZnO NPs was investigated extensively. The kinetics, thermodynamics and adsorption isotherm data were obtained from the batch experiment analysis of the Congo red dye, where the efficiency of adsorption of the sample was found to be ∼ 92%. The kinetics data analysis, indicated the adsorption process to be of pseudo-second order type. The Freundlich isotherm was found to be best fitted with R2 = 0.998, signifying a multilayer adsorption. Thermodynamic parameters, ΔH0 and ΔS0 were calculated. The negative value of ΔH0 (−5.644 kJ/mol) corresponded to an exothermic adsorption process and the positive value of ΔS0 (0.0108 J mol−1 K−1) signified the increased randomness at the interface of the adsorbate and the adsorbent.

Dopants and impurities can adsorb to surfaces and grain boundaries in ceramics, influencing the sintering kinetics and grain boundary mobility during processing. Ca is a common impurity in alumina that promotes grain growth at concentrations below the solubility limit, in contrast to the commonly observed solute-drag effect. Knowledge of the Ca solubility limit at temperatures relevant to processing is important to control microstructural evolution. Here we report on the experimentally measured solubility limit of Ca in α-alumina at 1400 °C and 1500 °C from equilibrated and quenched samples using standardized wavelength dispersive spectroscopy to be 32 ± 3 ppm and 45 ± 3 ppm, respectively. Together with the previously measured Ca solubility limit at 1600 °C, the enthalpy (0.95 eV per Ca) and vibrational entropy (-7.35 × 10−4 eV K-1 per Ca) of solution were determined. A negative vibrational entropy of solution indicates coulombic interactions between the Ca cations and charge compensating defects in α-alumina.

Biofilm and thrombus formation on surfaces results in significant morbidity and mortality worldwide, which highlights the importance of the development of efficacious fouling-prevention approaches. In this work, novel highly robust and superhydrophobic coatings with outstanding multiliquid repellency, bactericidal performance, and extremely low bacterial and blood adhesion are fabricated by a simple two-step dip-coating method. The coatings are prepared combining 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FAS-17)-coated hydrophobic zinc oxide and copper nanoparticles to construct hierarchical micro/nanostructures on commercial polyurethane (PU) sponges followed by polydimethylsiloxane (PDMS) treatment that is used to improve the binding degree between the nanoparticles and the sponge surface. The micro/nanotextured samples can repel various liquids including water, milk, coffee, juice, and blood. Relative to the original PU, the superhydrophobic characteristics of the fabricated sponge cause a significant reduction in the adhesion of bacteria (Staphylococcus aureus) by up to 99.9% over a 4-day period in a continuous drip-flow bioreactor. The sponge is also highly resistant to the adhesion of fibrinogen and activated platelets with ∼76 and 64% reduction, respectively, hence reducing the risk of blood coagulation and thrombus formation. More importantly, the sponge can sustain its superhydrophobicity even after being subjected to different types of harsh mechanical damage such as finger-wiping, knife-scratching, tape-peeling, hand-kneading, hand-rubbing, bending, compress-release (1000 cycles) tests, and 1000 cm sandpaper abrasion under 250 g of loading. Hence, this novel hybrid surface with robustness and the ability to resist blood adhesion and bacterial contamination makes it an attractive candidate for use in diverse application areas.

SPICE models are constructed for memristive devices to form associated biophysical neuron circuit models such as the Hodgkin–Huxley (HH) type II excitability neuron circuit model, the HH type III excitability neuron circuit model, the simplified HH neuron circuit model, the Morris–Lecar neuron circuit model, and the memristive based direct-current (DC) circuit model. Rigorous nonlinear circuit-theoretic principles are also applied to analyze the different behaviors of the generic memristor Na $$^{+}$$ -ion, K $$^{+}$$ -ion, and Ca $$^{++}$$ -ion channels forming these biophysical neuron circuit models. Detailed explanations and clarifications are presented on the memristive HH type II and HH type III axonal excitabilities based on mathematical analysis as well as the circuit models. This is done from the perspective of the spike patterns generated by both of these biophysical neuron circuit models. Moreover, various experimental studies have revealed a synchronous brain state known as gamma rhythms that are responsible for sensory, memory, and motor processes. This suggests that understanding how the gamma oscillation (30–100 Hz) is generated in the brain will be extremely important to unravel the link between the activity of an individual neuron and the cognitive processing achieved by a population of networked neurons. We thus also study the dynamics of an interconnected excitatory–inhibitory (E–I) network population, which is ubiquitous in the brain. Utilizing biophysical models of the E–I network, we investigate the generation of pyramidal-interneuronal network gamma (PING) rhythms caused by the external input to the network and the connectivity heterogeneities. The results reveal that synchronous strong PING and sparsely firing weak PING rhythms are generated based on the network connectivities and external input heterogeneities in simulations of 100 memristive HH type II excitability neurons forming an E–I network.

The occurrence of antibiotic resistant microorganisms in poultry litter is due to the increasing use of antibiotics. Poultry litter is used as a fertilizer for its high nutrient content. The presence of antibiotic resistant microorganisms in poultry litter makes its handling, amendment and application as fertilizer a challenging task. This study is designed to evaluate the antibiotic susceptibility and plasmid profiling of beta-lactamase producing multi-drug resistant Staphylococcus aureus in poultry litter. Sample collected from a poultry farm was screened for the presence of Staphylococcus aureus strains. The in vitro antibiotic susceptibility test by disk diffusion method were carried out in all the isolates. All the isolates were highly susceptible to oxacillin and gentamycin and intermediate for erythromycin and were completely resistant to vancomycin and penicillin. The isolated Staphylococcus aureus strains showed beta-lactamase activity which is the basis for the resistance to beta-lactum antibiotics. These strains when exposed to curing agent namely ethidium bromide, the beta-lactamase activity was lost. Results indicate that Staphylococcus aureus isolated from poultry litter are beta-lactamase producers and relatively resistant to commonly used antibiotics. The resistance among the isolated strains is found to be plasmid-mediated. The outcome of our present study exercises both usefulness in shaping the existing antibiotics prescription and thus helps to reduce or prevent the development of multiple drug resistant microorganism.

Hypothesis: Previous works have shown that many-body interactions induced by dispersants with increasing correlation length will generate a diminishing two-phase region [Soft Matter 14, 6921 (2018)]. We conjecture that the attenuation of the depletion attraction due to many-body interactions is a ubiquitous phenomenon in medium-induced interactions. We propose mixtures of colloidal particles and rod-like polymers as a feasible experimental system for verifying these predictions, since the intra-molecular correlations are not screened in a good solvent for rod-like polymers as they are in flexible polymers. The length of the rods can grow and become the dominant length scale that determines the range of the depletion interactions for the imbedded non-adsorbing particles. Simulations: We study many-body depletion forces induced by polymerizing rod-like polymers on spherical non-adsorbing colloids, using Metropolis Monte Carlo simulations. We also employ a simple mean-field theory to further justify our numerical predictions. Findings: We demonstrate that the phase diagram displays the same qualitative features that have previously been predicted by many-body theory, for mixtures containing flexible polymers under theta solvent conditions. The contraction of the particle two-phase region that we observe, as the correlation length increases beyond some specific value, could be a signature of the weakening of the depletion caused by many-body effects.

Cross-linked polymer electrolytes containing structurally dynamic disulfide bonds have been synthesized to investigate their combined ion transport and adhesive properties. Dynamic network polymers of varying cross-link densities are synthesized via thiol oxidation of a bisthiol monomer, 2,2'-(ethylenedioxy)diethanethiol, and tetrathiol cross-linker, pentaerythritol tetrakis(3-mercaptopropionate). At optimal loading of lithium bis(trifluoromethane-sulfonyl-imide) (LiTFSI) salt, the ionic conductivities (σ) at 90 °C are about 1 × 10

Hydrogen sulfide (H2S) is an endogenous gasotransmitter in the human body involved in various physiological functions including cytoprotection, maintaining homeostasis, and regulation of organ development. Therefore, H2S-releasing polymers that can imitate endogenous H2S release can offer great therapeutic potential. Despite decades of research, the use of H2S donors in medical device applications is mostly unexplored largely due to the challenge of the steady H2S release from a suitable polymeric platform that does not compromise the normal cellular functions of the host. In this work, an exogenous H2S release system was developed by integrating sodium sulfide (Na2S), a common H2S donor, into a medical-grade thermoplastic silicone-polycarbonate-urethane polymer, Carbosil 20 80A (hereon as Carbosil), via a facile solvent evaporation technique. The spatial distribution and nature of Na2S in Carbosil were characterized through X-ray diffraction (XRD) spectroscopy and field emission scanning electron microscopy (FESEM) with energy-dispersive spectroscopy (EDS), indicating an amorphous phase shift upon incorporating Na2S in Carbosil. The composite, Na2S-Carbosil, is responsive in physiological conditions, resulting in sustained H2S release measured for 3 h. In vitro cellular responses of 3T3 mouse fibroblasts, human lung epithelial (HLE), and primary human umbilical vein endothelial cells (HUVEC) were investigated. Fibroblast cells showed cell proliferation in 24 h and complete cell migration in 42 h in vitro. The Na2S-Carbosil composites were cytocompatible toward HUVEC and HLE cells. This study provided important in vitro proof of concept that warrants potential use of these H2S-releasing platforms in engineering biomedical devices, tissue engineering, and drug delivery applications.

An alkaliphile bacterial strain designated as CH11 was isolated from the sediments of Chilika Lake, Odisha. The isolate showed stupendous growth and production of α-amylase at pH 10.0. Through 16S rRNA gene based molecular technique this isolate was identified as Bacillus cereus strain SP-CH11 having GenBank Accession No. KT992791. Homogenous ~55 kDa extracellular α-amylase was extracted with 241.304, 26.26 and 3.2-fold acceleration in specific activity, purification fold and yield respectively. The alkaline α-amylase AA11 was further characterized. At pH 9.0 the purified enzyme AA11 was highly stable while retaining 88–100% functional viability at temperature range from 35 to 65 °C, confirming its thermostability nature. It showed stability with powdered and liquid detergents at 7 mg/mL and 100-fold dilutions respectively. AA11 efficiently removed the starch stain from cotton fabrics. The findings of this study indicate that the isolate CH11 is a source of novel alkaline α-amylase that has promising application in food and detergent industries.

The present work shows the effect of annealing conditions on the linear and nonlinear optical properties of two-year-old thermally evaporated 800 nm As40Se50Ge10 thin films. The aging effect in this film is clearly noticeable as compared with the old observation. The two-year-old films were annealed at different temperatures like 373, 413, 453 and 493 K for 1 h. The optical parameters were calculated from the optical transmittance and reflectance spectra measured at normal incidence of light by spectrometer in the 500–1000 nm range. The linear refractive index (n) and extinction coefficient (k) were decreased with annealing temperature. The observation reveals the increase in optical band gap with increase in annealing temperature while the width of the tail in the gap has an opposite behaviour. The oscillator energy, dispersion energy, dielectric constant, the loss factor, and optical conductivity were discussed in detail. The nonlinear refractive index and optical susceptibility were calculated by using Miller's formula which decreased with annealing temperature. The changes in both linear and nonlinear optical parameters with annealing temperature showed that annealing temperature can be considered as a useful factor for controlling the optical properties of As40Se50Ge10 chalcogenide films which could be the candidate for numerous photonic applications. The structural study was done by X-ray diffraction and Raman spectroscopy.

Electro-discharge machining (EDM) is a widely used process for manufacturing industries. It is a non-conventional machining process, where material is removed by the thermal energy of the generated electrical sparks between the electrode and workpiece. It is generally used to machine high strength temperature-resistance alloys which are difficult-to-machine. Titanium alloys being a difficult-to-machine alloy, is generally used for parts in aero-space industries, thus its machining should have a higher material removal rate, lower tool wear rate with better surface finish. To achieve these suitable machining responses the process is successfully optimized using Technique for Order Preference by Similarity to Ideal Solution (TOPSIS).

CdS as an n–type layer plays an important role in the fabrication of solar cells. Cd1-xCoxS thin-films with variable Co doping levels (x = 0 to 0.06) were deposited on glass and indium tin oxide-coated (ITO) glass substrates by simple and inexpensive chemical bath deposition. The effects of Co doping on the structural, optical, morphological, elemental, and vibrational properties of CdS films were systematically examined. XRD results revealed that Co concentrations increase and the crystallite size of the film decreases from 20.4 to 13.6 nm due to the incorporation Co in Cd sites. The optical bandgap was reduced from 2.44 to 2.32 eV due to the incorporation of Co, which was found with a UV–Vis spectrophotometer. Urbach energy, refractive index and extinction coefficient of all deposited films was estimated, and the results were discussed. The intensity of PL peaks was reduced by increasing the Co concentration in the red region. The resistivity and carrier concentration were measured from Hall measurement system and the film current density was increased from 7 to 26 mA/cm2 by cobalt doping.

Now-a-days metallic biodegradable biomaterial (MBB) has taken more attention by research people. From last few decades an enormous research has been done in magnesium, zinc and iron based MBB. Magnesium and zinc based alloys are now in final implementation stage whereas iron based alloys still in research stage. To take iron based alloys to the implement stage, a lot of research has been done by many research people for different aspects from last few decades. Among all iron based alloys, Fe-35Mn is one of them which show higher degradation rate in vitro as well as in vivo studies. In this study, effect of average particle size varies (from 30 to 80 µm) on degradation behavior and was completely investigated of the above alloy which is being prepared via powder metallurgy route. Fe-35Mn alloy pellets were sintered in a tube furnace at 1200 °C under Ar-5%H2 atmospheric pressure. SEM and DLS particle size analysis showed that 3 h milling time was the optimum time for the milling of initial powder sample. Smaller average particle size (35 µm) was responsible for uniform corrosion of Fe-35Mn alloy. Optical microscope analysis showed uniform corrosion on the surface of the sample. XRD results were also showed anti-ferromagnetic behavior as γ-Fe phase was present after sintering. Sintered density and porosity were calculated for each sample and showed that 3 h milling time particle size has higher porosity which affects the degradation rate during vitro study. Hardness results depicted 3 h alloy sample had better micro hardness value (143 ± 4Hv). Almost 34% porosity and 5.068 g/cm3 sintered density sample showed better corrosion rate (1.065 mm/yr) than pure iron (0.16 mm/yr) during static immersion test.

Mineral admixture concrete is proved to be beneficial to enhance strength and resistance of concrete against aggressive chemical environment. However, water binder (w/b) ratio is the major responsible factor to govern all the concrete material properties. So, for a strong and durable concrete, it is imperative to design a proper mix with suitable w/b ratio. The present study investigates the effects of w/b ratio on the compressive strength and acid resistance property of mineral admixture incorporated concrete. Fly ash (FA) and crusher dust (CD) were used in concrete as partial cement replacement at the level of 20%, 40%, and 60% to cast concrete cube of size (150 × 150 × 150) mm3 using three w/b ratios of 0.35, 0.38 and 0.4. The fresh concrete properties, the compressive strength of the different types of concrete samples at 365 days of water curing and the acid (5% H2SO4) resistance of those water cured concrete samples after 365 days of acid exposure have been investigated to study the impact of w/b on the strength and acid resistance properties of concrete. Full factorial DOE with ANOVA was conducted to determine the significance of the concrete type and w/b ratio on strength and strength loss of concrete under acid exposure. In addition, the Grey relational Analysis and the Response Surface Methodology (RSM) have been also used to find the impact of w/b ratio towards simultaneous optimization of strength and % strength loss on acid exposure to concrete.

In the current review, the failure analysis of gas turbine blades and to overcome those failures the development of materials have been discussed. The properties of a gas turbine blades should have exhibit have been reported in the current review. In addition to the above, the importance of coating in gas turbine blade has been listed. After the brief investigation of the failure analysis and materials developed it is observed that still there are some properties to be developed to obtain an optimum gas turbine blade.

Turning is one of the essential contact machining processes, which is often used to produce smooth profiles. However, mass machining of mild steel material with high speed steel is found to be challenging even using suitable coolant due to the inadequate process parameter sets affected by improper parametric correlation. Therefore, this work demonstrates the parametric optimization of turning for desired responses using Fuzzy-TOPSIS analysis. Taguchi method was used to design the experiments using L9 orthogonal array and the effect of each parameter on material removal rate, surface roughness and specific energy consumption while machining was studied collectively.

The excellent properties such as high strength to weight ratio and biocompatibility possessed by Titanium make it a highly beneficial material. Titanium is used in aerospace, armor plating, naval ships, missiles and surgical implants. In addition, the allotropic transformation nature of this metal further gives a wider scope of applications. The basic objective of this study is to review various aspects of titanium and titanium-based alloys used as orthopedic implants. An in-depth study on β-Titanium alloys is carried out with an aim to understand the dependency of mechanical properties and phases on the alloy composition with respect to biomedical applications. A comprehensive approach has been made to understand the design and synthesis procedure of the alloys.

Aluminium alloy-based metal matrix composites (AMMCs) have been considered as a potential material in various engineering and industrial applications due to their excellent combination of physical, mechanical and tribological properties. Reinforcing with different filler materials into the metallic matrix improves the hardness, stiffness, specific strength, wear resistance and fatigue properties of the materials in contrast with the conventional materials. The characteristics of aluminium alloy-based composite solely depend upon the type of fillers, interfacial bonding and different processing parameters. In this work, metal matrix composites have been fabricated by reinforcing Al2O3 in AA5754 matrix employing stir casting method. Mechanical characterisation, as well as the sliding wear test were carried out. The effect of the varying process parameters on the sliding wear properties has been investigated using Taguchi method and Grey Relational Analysis (GRA).

Surface integrity is an important feature of machined parts which has direct impact on their fatigue life as well as tribological properties. Surface roughness and residual stresses induced during machining are critical in determining surface integrity of a machined part. Turning process can induce triaxial residual stress in products which could be either tensile or compressive in nature. In this work, grey relational analysis is performed for multi optimization of different components of residual stress along with surface roughness based on experimental data taken from a given literature. Levels of influence of each of the cutting parameters namely feed rate, cutting speed, depth of cut, work piece hardness and tool edge geometry are found out for the multi objective optimization problem and optimum combinations of parameters are predicted. Observations are compared against available literature and limitations of current study and scope of further study are discussed.

The emergence of antibiotic-resistant bacteria is the biggest threat to our society. The rapid discovery of drug resistant bacteria is very urgently needed to guide antibiotic treatment development. The current manuscript reports the design of a 2D–0D heterostructure-based surface enhanced Raman spectroscopy (SERS) platform, which has the capability for the rapid identification of the multidrug resistant strain of Salmonella DT104. Details of the synthesis and characterization of the heterostructure SERS platform using a two dimensional (2D) WS2 transition metal dichalcogenide (TMD) and zero dimensional (0D) plasmonic gold nanoparticles (GNPs) have been reported. The current manuscript reveals that the 2D–0D heterostructure-based SERS platform exhibits extremely high Raman enhancement capabilities. Using Rh-6G and 4-ATP probe molecules, we determined that the SERS sensitivity is in the range of ∼10−10 to 10−11 M, several orders of magnitude higher than 2D-TMD on its own (10−3 M) or 0D-GNPs on their own (∼10−6 to 10−7 M). Experimental and theoretical finite-difference time-domain (FDTD) simulation data indicate that the synergistic effect of an electromagnetic mechanism (EM) and a chemical mechanism (CM) on the heterostructure is responsible for the excellent SERS enhancement observed. Notably, the experimental data reported here show that the heterostructure-based SERS has the ability to separate a multidrug resistance strain from a normal strain of Salmonella by monitoring the antibiotic–pathogen interaction within 90 minutes, even at a concentration of 100 CFU mL−1.

In this work, gold nanoparticles (AuNPs) were synthesised using the fresh leaves extract of Pongamia pinnata (PLE) and characterized using various analytical techniques such as UV–visible spectroscopy, TEM, SEM, EDX, and XRD. UV–Visible spectra showed surface plasmon resonance (SPR) peaks in the range of 520–540 nm signifying the synthesis of colloidal AuNPs stabilised by PLE. Further, we investigated the cytotoxic effects of AuNPs against human cervical cancer cell line (HeLa). MTT assay screened IC50 value of 200 μg/mL at 24 h for AuNPs formed at varying HAuCl4 concentration. Flow cytometry measurements using H2DCFDA showed that the toxicity of AuNPs was attributed to the generation of reactive oxygen species (ROS). Besides, the in vitro anticancer activities of AuNPs were studied in HeLa cells by several assays which resulted in altered cell morphology, reduced potential of wound healing, inactive mitochondria due to loss of mitochondrial membrane potential (MMP) and cell cycle arrest. AuNPs showed dose-dependent selective toxicity towards HeLa cells and were non-toxic against human embryonic kidney cell line (HEK293). The study revealed an efficient, ecofriendly and simple method for synthesis of multifunctional AuNPs using green synthetic approach with high anticancer potential for cervical cancer cell line.

Guided by brain-like ‘spiking’ computational frameworks, neuromorphic computing—brain-inspired computing for machine intelligence—promises to realize artificial intelligence while reducing the energy requirements of computing platforms. This interdisciplinary field began with the implementation of silicon circuits for biological neural routines, but has evolved to encompass the hardware implementation of algorithms with spike-based encoding and event-driven representations. Here we provide an overview of the developments in neuromorphic computing for both algorithms and hardware and highlight the fundamentals of learning and hardware frameworks. We discuss the main challenges and the future prospects of neuromorphic computing, with emphasis on algorithm–hardware codesign. The authors review the advantages and future prospects of neuromorphic computing, a multidisciplinary engineering concept for energy-efficient artificial intelligence with brain-inspired functionality.

Background In recent years, research on food packaging is gaining momentum, primarily being driven by consumer preferences to food quality and food safety. Also, as food packaging plays a pivotal role in product selection at retail outlets, the interest on developing novel strategies in food packaging is on the rise. One such concept with huge potential in the food industry is intelligent packaging. Scope and approach The focus of this work is to provide an up-to-date information on intelligent tools such as indicators (thermal indicators, leak indicators, freshness indicators, pH indicators), sensors, radio frequency identification tags and other essential aspects of intelligent packaging systems as reported in literature and those that have gained commercial value for applications in the food supply chain. Key findings and conclusions Emphasizing the potential of intelligent packaging, a range of products, including muscle-based foods, and fruits and vegetables are discussed. Importantly, this work highlights research needs, particularly in terms of applications for liquid foods, which are the most perishable commodities.

An alkali-tolerant bacterial isolate CH7 was isolated from Chilika Lake sediments that produced α-amylase at high pH. It showed >15 mm zone diameter at pH 11.0 on agar plate containing 1% starch hence considered for study. It survived up to 10% NaCl concentration on nutrient agar plates. Taxonomically it was identified as Bacillus sp. strain SP-CH7 having GenBank Accession No. KU761266. Optimized alkaline α-amylase, AA7 showed 202.857 specific activity (IU/mg), 65.95 purification fold and 25.94 yield (%) respectively. Molecular weight was revealed by SDS-PAGE as 55 kDa. The Km value was 0.688 mg/mL and so was 2.342 IU/mL Vmax obtained for AA7 towards starch. This enzyme showed 92.79% and 91.14% stability at pH 11.0 and 13.0 respectively and up to 75 °C stability was also noted. Enzyme activity was stimulated by Co2+, Na+ and Ca2+. It was stable in presence of EDTA, SDS, all the powdered detergents as well as with liquid detergent “Ezee” which vouches for its potential application in Detergent industries.

Most high load-bearing implants are metallic alloys which contain toxic chemical components that might be released due to the corrosive environment of body fluids and load-bearing activity. Surface modification techniques do not guarantee biocompatibility. Hence, the bioactive surface of implants can be modified by coating the surface with a suitable material that addresses the needs of the patient. The choice and application process of the coatings should be determined based on the workability of the material and its physiochemical properties, such as the procedures involved and performance in avoiding removal of any desirable material properties that are helpful in the tissue regeneration process. Tailor-made coating materials prove very promising, as they might improve permanent implantations, make them more affordable and reduce the need for surgical revisions. The scope of the featured properties, such as addition of accelerated tissue regeneration, antibacterial properties and controlled release and removal of debris from the biological system to the metal implants makes coatings an ideal choice for surface modification of implants. This report reviews several options available for forming a biologically active layer over metallic surfaces that will interact with and produce desirable effects on host tissues.

In this research work, the effect of plasma treatment on cotton fabric prior to in-situ polymerization of polypyrrole is studied. Cotton woven fabric samples are, individually, pre-treated with argon and nitrogen plasma. Samples that were pre-treated with argon plasma and then subjected to in-situ polymerization of polypyrrole show higher conductance in comparison with the sample pre-treated with nitrogen plasma. This is attributed to the increased interfacial bonding of the pyrrole ring with the argon functional groups.

A facile microwave-assisted combustion method was adopted to synthesize pure ZnO and Mg-doped ZnO nanoparticles (NPs), and characterization of the NPs and the sorption behavior with Congo Red (CR) Azo dye was extensively investigated. The structure, morphology and chemical assay of the synthesized NPs were studied with respect to the pure and 2% Mg-doped ZnO samples. The X-ray diffraction pattern confirmed the presence of crystalline, cubic phase with fluorite structure of both the NPs. The morphological differences between the pure and Mg-doped ZnO NPs were evaluated by FE-SEM, which revealed that the NPs were in the nanoscale regime with irregular crystalline morphology having a grain size of ~18–45 nm. N2 adsorption/desorption isotherms measured at −196 °C suggested a Type II structure with limited hysteresis loops, likely due to some interparticle porosity. The BET SSA ZnO NPs obtained was found to be 32 m2 g−1, indicating about its potential in sorption processes. Batch adsorption study for the removal of CR carried out showed that, the Mg-doped NPs showed higher loading efficiency (125 mg·g−1) than the ZnO NPs (25 mg·g−1) counterpart. This was corroborated by the isotherm results in which the CR dye sorption followed a Freundlich Isotherm model for both undoped ZnO and Mg-doped ZnO NPs. The sorption of CR dye followed a pseudo-second order kinetics. The negative ΔG° (−31.91 and −109.41 kJ mol−1) showed the feasibility of the adsorption process. The ΔH° was determined as +13.74 kJ mol−1 and 50.7 kJ mol−1 for ZnO NPs and Mg doped-ZnO NPs respectively, confirming the endothermic nature of the adsorption for removing CR dye from the solution.

Modern crises in implantable or indwelling blood-contacting medical devices are mainly due to the dual problems of infection and thrombogenicity. There is a paucity of biomaterials that can address both problems simultaneously through a singular platform. Taking cues from the body's own defense mechanism against infection and blood clotting (thrombosis) via the endogenous gasotransmitter nitric oxide (NO), both of these issues are addressed through the development of a layered S-nitroso-N-acetylpenicillamine (SNAP)-doped polymer with a blended selenium (Se)-polymer interface. The unique capability of the SNAP-Se-1 polymer composites to explicitly release NO from the SNAP reservoir as well as generate NO via the incorporated Se is reported for the first time. The NO release from the SNAP-doped polymer increased substantially in the presence of the Se interface. The Se interface was able to generate NO in the presence of S-nitrosoglutathione (GSNO) and glutathione (GSH), demonstrating the capability of generating NO from endogenous S-nitrosothiols (RSNO). Scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) traced distribution of elemental Se nanoparticles on the interface and the surface properties were evaluated by surface wettability and roughness. The SNAP-Se-1 efficiently inhibited the growth of bacteria and reduced platelet adhesion while showing minimal cytotoxicity, thus potentially eliminating the risks of systemic antibiotic and blood coagulation therapy. The SNAP-Se-1 exhibited antibacterial activity of ∼2.39 and ∼2.25 log reductions in the growth of clinically challenging adhered Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. SNAP-Se-1 also significantly reduced platelet adhesion by 85.5% compared to corresponding controls. A WST-8-based cell viability test performed on NIH 3T3 mouse fibroblast cells provided supporting evidence for the potential biocompatibility of the material in vitro. These results highlight the prospective utility of SNAP-Se-1 as a blood-contacting infection-resistant biomaterial in vitro which can be further tuned by application specificity.

Li-ion batteries discover its way in developing new electrodes with recent advancements. In regardless, the new electrode materials necessity is to fulfill the high voltage operation with high current rate for Li-ion batteries. Hence, LiCoxV2O5 (x = 0.1, 0.3 and 0.5) were synthesized by one pot hydrothermal synthesis followed by post calcination. The powder X-ray diffractometer explains the formation of LiCoxV2O5 (x = 0.1, 0.3 and 0.5) with more than two phases as the cobalt concentration increases with increased grain size. FE-SEM and HR-TEM studies of the as-synthesized materials shows the formation of sphere and rod like morphologies. Cyclic voltammograms reveal an excellent redox peaks for Co and V, the redox peaks were observed between 2.0 and 4.5 V. LiCo0.1V2O5 material delivered high reversible capacity of 147mAh/g especially at high current density as well as withstand stable discharge capacity up to 50 cycles. The charge-discharge cycling of LiCo0.1V2O5 cathode materials at various rates 0.5C, 1C, 2C, 3C and 4C delivered specific discharge capacities of 147mAh/g, 129mAh/g, 113mAh/g, 98mAh/g and 85mAh/g with 96% columbic efficiency. Also it shows the lower charge transfer resistance with less interfacial properties, which contributed to the improved rate capability with stable cycling. Thus this material serves as promising cathode material for rechargeable Li-ion batteries.

Biomediated synthesis of gold nanoparticles (AuNPs) using plant extract is a favorable alternative to traditional physicochemical based methods. Biological synthesis assists in the generation of stable and biocompatible nanoparticles (NPs). The aim of the present work was to fabricate AuNPs using Pongamia pinnata leave extract. The synthesized AuNPs were characterized by various analytical techniques such as UV–visible spectroscopy, TEM, EDX, and XRD. Absorption spectra showed SPR peaks in the range of 520–540 nm signifying the formation of AuNPs stabilized by P. pinnata extract. The average size of NPs was found in the range 10–25 nm as obtained from TEM analysis. Moreover, the synthesized NPs showed antifungal activity. The antifungal activities of AuNPs were tested against oomycetes SR1 and BP1120. The MIC80 value was observed at the concentrations 1.6 and 0.8 mg/mL of AuNPs in SR1 and BP1120 fungus, respectively. The study revealed an efficient, eco-friendly and simple method for synthesis of stable AuNPs using green synthetic approach.

In this study, we propose a simple and versatile tri-modal (colorimetric, fluorometric, and electrochemical) means for detection of riboflavin using silver carbon dot (Ag@CD) nanoconjugates. Hydroxyl-rich carbon dot (CD) synthesized by microwave-assisted method using citric acid and PEG was used as reductant for Ag@CD formation. Effect of CD and AgNO3 concentration on Ag@CD synthesis was examined. Furthermore, we observed that the Ag@CD conjugates were capable of selectively detecting riboflavin. The sensing mechanism was based on aggregation of nanoconjugates as confirmed from scanning electron microscope micrographs. Red shifting of surface plasmon resonance peaks to around 550 nm concomitant with quenching and red shift of fluorescence peak was observed. Colorimetric assay showed a change in colour of assay mixture to red and detection limit of 2.5 µM was observed. In addition, electrochemical detection showed a high selectivity for riboflavin even in the presence of interfering analytes with a sensitivity of 1.56 µA/mM/cm2. This rationally designed tri-modal sensing platform offers simplicity of operation and faster detection which may be developed into a point-of-care diagnostic device.

The Nanomaterial is a pioneer in the field of modern research for its unique properties. Human exposure analysis is inevitable due to the rapid growth in technology. The concern for human welfare indicates a need for reduction of human exposure towards the radiation caused by the devices. The dielectric properties of the nanomaterials can be ideal for exploration in the field of biomedical engineering. Specific absorption rate (SAR) is a vital parameter for exposure analysis. This paper investigates the impact of Nanomaterials on the human exposure analysis. For this purpose, a dipole radiating structure operating at GSM frequency of 900 MHz and 1800 MHz are designed with conventional Copper material and compared with Carbon nanomaterials such as Graphene, Single-walled carbon nanotube (SWCNT) and Multi-walled carbon nanotube (MWCNT) for performance evaluation. Further, the specific absorption rate estimates absorption of radiation in IEEE Sam phantom human head with equivalent tissue properties. The comparison of calculated SAR with the radiating structures that are designed with the equivalent properties of that of Nanomaterials. The evaluation of Nanomaterial Antennas at the center frequency is estimated, and performance is evaluated. The designed Nanomaterials interact with IEEE SAM Phantom and SAR is calculated. The analysis of SAR impact with nanomaterials is investigated in this work.

The development of infection-resistant materials is of substantial importance as seen with an increase in antibiotic resistance. In this project, the nitric oxide (NO)-releasing polymer has an added topcoat of zinc oxide nanoparticle (ZnO-NP) to improve NO-release and match the endogenous NO flux (0.5-4 × 10-10 mol cm-2 min-1 ). The ZnO-NP is incorporated to act as a catalyst and provide the additional benefit of acting synergistically with NO as an antimicrobial agent. The ZnO-NP topcoat is applied on a polycarbonate-based polyurethane (CarboSil) that contains blended NO donor, S-nitroso-N-acetylpenicillamine (SNAP). This sample, SNAP-ZnO, continuously sustained NO release above 0.5 × 10-10 mol cm-2 min-1 for 14 days while samples containing only SNAP dropped below physiological levels within 24 h. The ZnO-NP topcoat improved NO release and reduced the amount of SNAP leached by 55% over a 7-day period. ICP-MS data observed negligible Zn ion release into the environment, suggesting longevity of the catalyst within the material. Compared to samples with no NO-release, the SNAP-ZnO films had a 99.03% killing efficacy against Staphylococcus aureus and 87.62% killing efficacy against Pseudomonas aeruginosa. A cell cytotoxicity study using mouse fibroblast 3T3 cells also noted no significant difference in viability between the controls and the SNAP-ZnO material, indicating no toxicity toward mammalian cells. The studies indicate that the synergy of combining a metal ion catalyst with a NO-releasing polymer significantly improved NO-release kinetics and antimicrobial activity for device coating applications. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 00A: 000-000, 2019.

Urinary catheterization is one of the most common medical procedures that makes a patient susceptible to infection due to biofilm formation on the urinary catheter. Catheter associated urinary tract infections (CAUTIs) are responsible for over 1 million cases in the United States alone and cost the healthcare industry more than $350 million every year. This work presents a liquid-infused nitric-oxide-releasing (LINORel) urinary catheter fabricated by incorporating the nitric oxide (NO) donor S-nitroso-N-acetylpenicillamine (SNAP) and silicone oil into commercial silicone Foley catheters through a two-stage swelling process. This synergistic combination improves NO-releasing materials by providing minimal SNAP leaching and a more controlled release of NO while incorporating the nonfouling characteristics of liquid-infused materials. The LINORel urinary catheter was successful in sustaining a controlled NO release over a 60 day period under physiological conditions with minimal SNAP leaching during the initial 24 h period, 0.49 ± 0.0061%. The LINORel-UC proved successful in reducing bacterial adhesion and biofilm formation for Gram positive Staphylococcus aureus (98.49 ± 2.06%) over a 7 day period in a drip flow bioreactor environment. Overall, this study presents a desirable combination that incorporates the antifouling advantages of liquid-infused materials with the active release of a bactericidal agent, an uncharted territory in aiding to prevent the risk of CAUTIs.

The present work reports the amorphous-crystalline phase transformation in thermally evaporated As50Se50 thin films upon annealing at below Tg (423 K) and above Tg (523 K). The structural transition was probed by XRD, Raman and X-ray photoelectron spectroscopy. The composition and surface morphology were probed by EDS and FESEM techniques. The transmittance and reflectance spectra over the wavelength range 500 nm–1200 nm were used to deduce the optical parameters. The various optical parameters of the as-prepared and annealed As50Se50 thin films were estimated and discussed in terms of density of defect states and disorders. The indirect optical energy gap decreased for the 423 K annealed film and abruptly increased for 523 K annealed film as compared to the as-prepared film. The Swanepoel envelope method, WDD model, and Sellemeire postulates were employed for the analysis of refractive index, static refractive index, oscillator energy, dispersion energy, oscillator wavelength and dielectric constant. The changes in the linear and nonlinear properties showed opposite behavior for the two annealed films. The non-linear refractive index and 3rd order susceptibility were found to be increased for 423 K annealed film and decreased for the 523 K annealed film. The optical as well as the electrical conductivity changed with annealing and the electrical susceptibility increased for 523 K annealed film. The tunable optical properties can be applied for several optoelectronic applications. The amorphous to crystalline structural transformation occurred at annealing above Tg. The 3rd order susceptibility was found to be more at 423 K annealing and less at 523 K annealing.

In vitro, cellular processing on polymeric surfaces is fundamental to the development of biosensors, scaffolds for tissue engineering and transplantation. However, the effect of surface energy and roughness on the cell–surface interaction remains inconclusive, indicating a lack of complete understanding of the phenomenon. Here, we study the effect of surface energy (Es) and roughness ratio (r) of a polydimethylsiloxane (PDMS) substrate on cell attachment, growth, and proliferation. We considered two different cell lines, HeLa and MDA MB 231, and rough PDMS surfaces of different surface energy in the range Es = 21–100 mJ m−2, corresponding to WCA 161°–1°, and roughness ratio in the range r = 1.05–3, corresponding to roughness 5–150 nm. We find that the cell attachment process proceeds through three different stages marked by an increase in the number of attached cells with time (stage I), flattening of cells (stage II), and elongation of cells (III) on the surface. Our study reveals that moderate surface energy (Es ≈ 70 mJ m−2) and intermediate roughness ratio (r ≈ 2) constitute the most favourable conditions for efficient cell adhesion, growth, and proliferation. A theoretical model based on the minimization of the total free energy of the cell–substrate system is presented and is used to predict the spread length of cells that compares well with the corresponding experimental data within 10%. The performance and reusability of the rough PDMS surface of moderate energy and roughness prepared via facile surface modification are compared with standard T-25 cell culture plates for cell growth and proliferation, which shows that the proposed surface is an attractive choice for efficient cell culture.