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Trends show that strategies for effective utilization of food wastes will emerge as a key field of research and markets shortly. In this study, for the first time, 3D printing technology, an emerging approach for food customization, was used to prepare nutrient-rich noodles from peel wastes obtained from potato processing industries. The study involves the characterization of material properties for 3D printing. Based on the analysis, the fine fractions of potato peel were found to exhibit better printability than the coarse fractions. Whole wheat flour and potato peel powder were used to formulate the material supply (60:40), and extrusion printing conditions for the in-house developed CARK printer were optimized at 600-mm/min printing speed, 600-rpm extrusion motor speed, and 6-bar pressure for a 1.28-mm-diameter nozzle. Consumer acceptance of the 3D printed and post-processed instant noodles were on par with the market product; with an energy value of 414.39 kcal/100 g, the formulated noodles can be a good choice for breakfast. Importantly, the concept provides new insights to improved utilization of food waste streams; 3D printed foods can be nutrient-rich as well as customized to any shape or layering for enhanced product acceptability. Further, the technology can be conveniently scaled up and the approach is sustainable.

A detailed investigation was conducted to study the concurrent effect of temperature and strain rate on the microstructure evolution in Ti–5Al–3Mo–1.5V dual-phase Titanium alloy. By applying varying strain rates from $$10^{-3} $$ to 10 $$\hbox {s}^{-1}$$ between 1098 and 1298 K at an interval of 50 K, isothermal compression characteristics and microstructural changes were recorded. The sizes of globules, concentrated predominantly at the lamellar kinks, were found to be inversely proportional to the strain rate. Further, a dynamic material model was employed to assess and plot the processing map displaying the safe hot working regime. The apparent hot-working activation energy in the $$\alpha +\beta $$ and $$\beta $$ phase field was 636 kJ/mol and 379 kJ/mol, respectively. A higher activation energy than the self-diffusion threshold of the $$\alpha +\beta $$ and $$\beta $$ field was attributed to lamellae breakup and dynamic recrystallization in the respective phase fields. The microstructure analysis and identified softening mechanisms further helped in concluding the safe hot working regime to be 1248 K and 10 $$^{-3}$$ $$\hbox {s}^{-1}$$ .

In the present study, graphene nanoplatelets (GNPs: 1–2 wt. %) reinforced TiN coating were successfully fabricated over titanium alloy using a reactive shroud plasma spraying technique. All coatings were completely oxide free, while the addition of GNPs suppressed the non-stoichiometric TiN0.3 phase. Improvement of 19%, 18% and 300% in hardness, elastic modulus and fracture toughness was achieved by mere addition of 2 wt. % GNP. The addition of GNP in TiN also reduced the wear volume loss and the wear rate of the coatings for the entire range of temperature (293–873 K). Moreover, GNPs also manifested the coefficient of friction (COF) of the coating. Post wear characterization revealed that the presence of GNP throughout the wear track even at 873 K. The multi-layer structure of GNPs assisted in long term lubricity to the surface and increased the wear resistance of the coating.

The article presents the results of tests to assess stretchability of commercial purity titanium sheet. The plastic strain ratio (r value) indicates strong normal anisotropy and weak planar anisotropy in the plastic properties. The forming limit diagram (FLD), determined by hemispherical punch stretching, exhibits limiting strains that are large at the smallest strain ratios, low at plane strain, and minimum at a strain ratio close to equibiaxial stretching. Hill’s criterion for localized necking, in conjunction with a best fit constitutive equation from the tensile test and the quadratic Hill’s yield surface, predicts the negative minor strain region of the FLD well. However, fracture as the mechanism limiting the deformation cannot be ruled out, especially as the negative minor strain region extends to the positive side with a minimum in the positive side. The increase in limit strains in the positive minor strain region beyond the minimum and the plane strain condition occurring in full dome stretching are explained as “anomalies” due to planar anisotropy. Electron backscatter diffraction (EBSD) studies show a strong basal texture that intensifies when deformed under plane strain and equibiaxial conditions. Under uniaxial tension, the basal plane texture changed to $$ \left\{ {0001} \right\}\left\langle {11\bar{2}0} \right\rangle $$ texture. Twinning is also found to be more under uniaxial tension. Trends in the mechanical properties correlate well with the EBSD results.

An investigation was conducted to understand the role of microstructure on the asymmetry of mechanical properties in quasi-static tension and compression in a two-phase titanium alloy Ti-5Al-3Mo-1.5V. Different microstructures were obtained (lamellar colony, basketweave and martensitic) on adopting different cooling rates after solution treatment in single phase β region. The microstructure with martensite exhibited higher strain to failure and lower yield strength than basketweave. Detailed TEM microstructural analysis helped reveal the existence of compression twins and strain-induced phase transformation in compression and tension tests respectively, both of which are relatively rare to be observed in two-phase titanium alloys.

We report in situ fabrication of oxide-free titanium nitride (TiN) coating by conventional plasma spraying technique. Complete oxide free TiN coating without using low pressure or vacuum environment was achieved by using the N2 shroud with plasma spraying. X-Ray diffraction and Transmission electron microscope confirmed the absence of any traces of oxide in the coating. Coating showed exceptionally higher mechanical properties (H: ∼18 GPa; E: ∼317 GPa). Outstanding reduction of ∼15 times in wear rate and ∼4 times in corrosion rate was observed compared to bare substrate (i.e. Ti-6Al-4V).

A β-solidified nearly lamellar γ-TiAl ( α 2 + γ ) based alloy was investigated to understand the evolution of microstructure during hot isothermal compression test at 1050 °C (below eutectoid). Cylindrical samples were compressed to different true strains up to 60%. The deformed samples were then characterized using scanning electron microscopy (SEM), electron backscattered diffraction (EBSD) and transmission electron microscopy (TEM) to understand the active deformation mechanisms. Dynamic flow softening behavior, i.e., dynamic recrystallization (DRX) type flow was observed. While no new strain induced phases were observed, there were minor changes in the phase fractions as a function of strain. Kinking and bending of lamellae at certain areas in the microstructure of compressed samples were predominant. Preliminary analysis by TEM indicated the presence of twinning in both γ and β phases.

In present study dissimilar metal joints between austenitic stainless steel (modified SS321) and α-Ti alloy (Ti-5Al-2.5Sn ELI) were produced by solid-state diffusion bonding process performed at different temperatures (750–950 °C) in vacuum. The effects of bonding temperature, time and pressure on interface microchemistry and microstructure were analyzed and subsequently the local hardness of interface layer(s) and the bond (shear) strength of the joints were evaluated. The results indicate the formation of four layers comprised of intermetallic phases viz. σ, χ, λ + Fe2Ti + FeTi and β-Ti at the joint interface, and their width increased with increase in the bonding temperature and time. The maximum shear strength of ~348 MPa, which is ~65% of the shear strength of SS321, was noted for the joint formed at the bonding temperature of 850 °C. This was achieved primarily due to complete collapse of surface asperities making intimate contact at the joint surface with formation of optimal width of interface layers having minimum embrittlement effect. The fractography of the specimens failed under shear loading revealed the transition of failure of the joints from featureless brittle fracture to mixed mode of ductile-brittle failure to quasi-cleavage brittle fracture with increasing the bonding temperature. Furthermore, it was noticed that the bonded joint specimens failed either through χ (layer 2) or λ + Fe2Ti + FeTi (layer 3). Interestingly, the optimized diffusion bonding parameters of the dissimilar metal joints of SS321/Ti-5Al-2.5Sn ELI have yielded different shear strength levels for the similar metal joints of SS321/SS321 (~35% of base alloy) and Ti-5Al-2.5Sn ELI/Ti-5Al-2.5Sn ELI (75% of base alloy).

The catalytic reduction of methylene blue was studied using biosynthesised gold-silver (Au-Ag) alloy nanoparticles (NPs). The fungal biomass of Trichoderma harzianum was used as a reducing and stabilising agent in the synthesis of Au-Ag alloy NPs. The synthesised NPs were well characterised by UV-vis spectroscopy, dynamic light scattering, X-ray diffraction, transmission electron microscopy, energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy. The plausible synthesis mechanism involved in the formation of Au-Ag alloy NPs was also discussed with diagrammatic representation. A series of experiments was performed to investigate the catalytic activity of the as-prepared Au-Ag alloy NPs and found that the alloy NPs show excellent catalytic activity.

The present work reveals the simple and rapid biomimetic approach for the synthesis of hydroxyapatite (HAp) nanofibers using yeast extract. The photocatalytic activity of the HAp nanofibers was investigated using methylene blue (M.B.) dye in a photocatalytic reactor. The synthesis of HAp nanofibers was confirmed by X-ray diffraction (XRD), Energy dispersive X-ray spectroscopy (EDX), Transmission electron microscopy (TEM), Selected-area electron diffraction (SAED) and Fourier transform infrared spectroscopy (FTIR). The photocatalytic activity of the HAp nanofibers was evaluated using reaction kinetics and its plausible mechanism was also studied. The results affirm that HAp nanofibers have suitable capability for degradation of M.B.

The present study demonstrates a simple, cost effective and selective method for colorimetric detection of mercury(II) ions using gold nanoparticles (AuNPs) synthesized by non-pathogenic and agriculturally considerable fungal biomass of Trichoderma harzianum ( T. harzianum ). The synthesized nanoparticles were characterized by UV–vis spectroscopy (UV–vis), dynamic light scattering (DLS), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The as-synthesized AuNPs were used further for the selective optical detection of Hg 2+ ions. The color of AuNPs solution changes in the presence of Hg 2+ ions and also a substantial change in the surface plasmon resonance (SPR) of nanoparticles was observed even at minute concentration of Hg 2+ ions. The sensitivity and selectivity of AuNPs towards Hg 2+ ions was also analyzed in the presence of Pb 2+ , Zn 2+ , Cd 2+ , Fe 3+ , Ni 2+ , Ca 2+ , Mn 2+ , Al 3+ , Co 2+ and Na + ions. The mechanism of colorimetric detection of Hg 2+ ions was also discussed along with diagrammatic representation.

We demonstrate a novel, unprecedented and eco-friendly mode for the biosynthesis of zinc oxide (ZnO) nanoflowers at ambient room temperature using Bacillus licheniformis MTCC 9555 and assessed their photocatalytic activity. The photocatalytic degradation of methylene blue (MB) dye was analyzed under UV-irradiation. An enhanced photocatalytic activity of ZnO nanoflowers was obtained compared to the earlier reports on ZnO nanostructures and other photocatalytic materials. The mechanism behind the enhanced photocatalytic activity was illustrated with diagrammatic representation. It is assumed that due to larger content of oxygen vacancy ZnO nanoflowers shows enhanced photocatalytic activity. Photostability of ZnO nanoflowers was analyzed for consecutive 3 cycles. The size and morphology of ZnO nanoflowers have been characterized by SEM, TEM and found to be in the size range of 250 nm to 1 μm with flower like morphology. It was found that ZnO nanoflowers was formed by agglomeration of ZnO nanorods. Further the EDX established the presence of the elemental signal of the Zn and O. XRD spectrum of ZnO nanoflowers confirmed 2θ values analogous to the ZnO nanocrystal. FTIR analysis was carried to determine the probable biomolecules responsible for stabilization of ZnO nanoflowers. The plausible mechanism behind the synthesis of ZnO nanoflowers by Bacillus licheniformis MTCC 9555 was also discussed with diagram representation.

Objective of the study To assess the saccular function using the vestibular evoked myogenic potential (VEMP) test in children with severe to profound sensorineural hearing loss. Methods 15 children (12 males and 3 females) with severe to profound sensorineural hearing loss in the age range of 4–12 years constituted the study group. 10 children (6 males and 4 females) with normal hearing constituted the control group. All the children were evaluated for saccular function by using the vestibular evoked myogenic potentials (VEMP). Results For study group the mean P1 and N1 latencies values were 15.12 ms and 23.86 ms, respectively. For control group the mean P1 and N1 latencies were 15.39 ms and 23.68 ms. The comparison of mean P1 and N1 latencies values between study and control groups revealed no significant difference (p > 0.05). Furthermore, the mean amplitude values of VEMP responses for study and control groups were 75.78 μV and 160.51 μV, respectively. The comparison mean amplitude values between study and control groups revealed statistically significant difference (p

The present work demonstrates the photocatalytic activity of biologically synthesized cadmium sulfide (CdS) nanoparticles, using the fungal biomass of Trichoderma harzianum. The photocatalytic activity of the nanoparticles was determined upon the degradation of methylene blue (M.B.) in a photocatalytic reactor and the residual concentration was monitored using UV-Vis spectroscopy. The mechanism behind the photocatalytic activity was discussed with a diagrammatic representation. The synthesized CdS nanoparticles were characterized by UV-Vis spectroscopy, Transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The UV-Vis spectrum of the CdS nanoparticles suspension showed an absorption peak at 332 nm. The photocatalytic activity of the CdS nanoparticles was evaluated using reaction kinetics. The energy band gap of the synthesized CdS nanoparticles was estimated by absorbance spectra. TEM analysis showed that the particles are formed on the nano scale and have a spherical morphology. X-ray diffraction analysis showed intense peaks which correspond to the crystalline nature of CdS. Fourier transform infrared spectroscopy provided clear evidence of the presence of proteins as probable biomolecules responsible for the stabilization of the CdS nanoparticles.

The present study demonstrates the biosynthesis of silver nanoparticles using Trichoderma koningii and evaluation of their antibacterial activity. Trichoderma koningii secretes proteins and enzymes that act as reducing and capping agent. The biosynthesized silver nanoparticles (AgNPs) were characterized by UV–Vis spectroscopy, dynamic light scattering (DLS), transmission electron microscopy (TEM) and x-ray diffraction (XRD). UV–Vis spectra showed absorbance peak at 413 nm corresponding to the surface plasmon resonance of silver nanoparticles. DLS was used to find out the size distribution profile. The size and morphology of the AgNPs was determined by TEM, which shows the formation of spherical nanoparticles in the size range of 8–24 nm. X-ray diffraction showed intense peaks corresponding to the crystalline silver. The antibacterial activity of biosynthesized AgNPs was evaluated by growth curve and inhibition zone and it was found that the AgNPs show potential effective antibacterial activity.