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Incremental sheet metal forming (ISMF) is one of the most innovative flexible processes for small volume production of complex sheet metal components. Formability of titanium grade 2 sheets is limited at room temperature and can be improved by forming at elevated temperature. Therefore, warm ISMF process has been explored to enhance the material formability. In this paper, thermal model has been proposed to predict the effect of temperature on the formability of sheet metal in warm ISMF process. Sine law has been used to determine the final thickness of the formed sheets. Experimental investigations on titanium grade 2 sheet at warm temperature has been carried out to study the effects of incremental depth, wall angle, and temperature on formability, geometrical accuracy, and thickness reduction during warm ISMF process using Taguchi L9 orthogonal array. Based on the experimental results, it was found that titanium grade 2 sheets formed with incremental depth of 0.1 mm and temperature of 300 °C showed higher formability with geometrical deviation of 1.52% and thickness reduction of 37.90%. Predictions of thermal model are validated by experimental work, and it has been found that experimental results are in good agreement with the thermal model. Analysis of variance (ANOVA) was used to identify the percentage contribution of each process parameters. To analyze the fracture behavior of the formed component, fractography study has been carried out using scanning electron microscopy (SEM).

Chromium(III)-doped nickel–ferrite nanoparticles, with the general formula Ni0.5Co0.5CrxFe2−xO4 (x = 0.0, 0.10, and 0.20), were prepared by the sol–gel method. The prepared samples were sintered at 700°C for 5 hr. The XRD result showed that the prepared samples are in single-phase partially inverse cubic spinel ferrite structures with space group Fd3m. From the XRD characterization, the average crystallite size for all samples decreased from 39.54 to 30.42 nm and the lattice parameters are found to be 0.8324, 0.8320, and 0.8314 nm for x = 0.0, 0.10, and 0.20, respectively. The energy dispersive X-ray (EDX) spectroscopy analysis confirmed the presence of all ions as per the stoichiometric ratios. The vibrating sample magnetometer measurements revealed that the saturation magnetization (Ms), remnant magnetization (Mr), and coercive fields are found to be decreased with increasing concentration of Cr3+ ions. The UV–vis spectroscopy analysis showed that the energy bandgap (Eg) increased with increasing the concentration of Cr3+ ion from 1.61 to 1.96 eV. The Fourier transform infrared spectra show the two main absorption bands at 407–424 cm−1 and 547–588 cm−1 corresponding to stretching vibrations of metal–oxygen in the octahedral and tetrahedral sites, respectively.

We studied the community composition of microzooplankton (MZP) from the surface waters off Candolim, Goa. The MZP communities were examined for the year 2013, covering different seasons and four stations (Near-shore: G3 & G4, offshore: G5 & G6). A total of 30 species belonging to 24 genera were recorded, which include loricate ciliates (LC: 14 species of 13 genera), aloricate ciliates (ALC: 5 species of 3 genera), heterotrophic dinoflagellates (HDS: 11 species of 8 genera), and copepod nauplii. The MZP abundance in the coastal waters varied spatially irrespective of different seasons, with higher abundance in the offshore stations (G5 & G6, 38–127 cells L-1) and lower abundance in the near-shore stations (G3 & G4, 20–97 cells L-1). The MZP community composition showed the dominance of HDS (16–85%) in the near-shore stations during most of the seasons and inferiority during NEM (16–18%). Moreover, all the coastal waters (near and offshore) were dominated by HDS (58–85%) during spring inter-monsoon. The dominant species of HDS were Dinophysis apicata , Dinophysis caudata , Prorocentrum micans , Protoperidinium breve , Protoperidinium latistriatum , and Protoperidinium granii. The statistical analysis (Canonical correspondence analysis and Spearman’s rank correlation) depicts that the MZP abundance and community composition were mainly controlled by salinity ( r = 0.4–0.7). Whereas the dominance of HDS in the coastal waters could be the reason for its mixotrophic nature and diverse feeding mechanism. Thus, a strong positive correlation between the HDS and LC ( r = 0.73–0.92) showed the feeding ability of HDS in their relative community.

Recombinant human platelet-derived growth factor-BB (rhPDGF-BB) promotes soft tissue and bone healing, and is Food and Drug Administration-approved for treatment of diabetic ulcers and periodontal defects. The short half-life of topical rhPDGF-BB protein application necessitates bolus, high-dose delivery. Gene therapy enables sustained local growth factor production. A novel gene activated matrix delivering polyplexes of polyethylenimine (PEI)-plasmid DNA encoding PDGF was evaluated for promotion of periodontal wound repair in vivo . PEI-pPDGF-B polyplexes were tested in human periodontal ligament fibroblasts and human gingival fibroblasts for cell viability and transfection efficiency. Collagen scaffolds containing PEI-pPDGF-B polyplexes at two doses, rhPDGF-BB, PEI vector or collagen alone were randomly delivered to experimentally induced tooth-supporting periodontal defects in a rodent model. Mandibulae were collected at 21 days for histologic observation and histomorphometry. PEI-pPDGF-B polyplexes were biocompatible to cells tested and enzyme-linked immunosorbent assay confirmed the functionality of transfection. Significantly greater osteogenesis was observed for collagen alone and rhPDGF-BB versus the PEI-containing groups. Defects treated with sustained PDGF gene delivery demonstrated delayed healing coupled with sustained inflammatory cell infiltrates lateral to the osseous defects. Continuous PDGF-BB production by nonviral gene therapy could have delayed bone healing. This nonviral gene delivery system in this model appeared to prolong inflammatory response, slowing alveolar bone regeneration in vivo .

A novel nitrogen rich energetic salt Melamine-melaminium 2-acetyl benzoate dihydrate (MMH + AB − 2) has been grown by slow evaporation method at room temperature. Single crystal X-ray diffraction studies reveals that the grown synthesized salt crystallizes in the centrosymmetric space group `c 2yc’ of the monoclinic system. The lattice parameters were established as a  = 12.286(3) (Å), b  = 18.934(4) (Å), c  = 18.515(4) (Å), α  =  γ  = 90 ∘ Å , and β  = 95.26 ( 3 ) ∘ Å , volume of the unit cell V  = 4288.9 (15) (Å) 3 . The intermolecular hydrogen bond N–H···N, N–H···O, C-H···O, and O–H···O type interactions stabilize the structure and lead to the three-dimensional network. Fourier Transform Infrared and Raman Spectra were used to study the compound's structural groups. FT-NMR studies confirm the structure of the grown MMH + AB −2 crystal. The optical properties of the crystal were investigated using UV–Visible spectroscopy measurements. In the UV region, excitation begins at 200 nm, with the first absorption peak observed at a wavelength of 272.53 nm, followed by a second peak at 281.41 nm. The cut-off wavelength is 300 nm. The theoretical and experimental refractive index values are 2.84 and 1.69, respectively. The energy band gap value obtained from Tauc’s plot from UV–Vis data is 4.070 eV. Optical studies, such as refractive index and band gap measurements, were conducted to assess the material’s transparency. HOMO–LUMO transitions and its energy gap are computed to be 5.614 eV and other related molecular properties have also been calculated to reveal the optical properties. In the PL study, excitation starts at a wavelength of 350 nm and the emission peak occurs at 387.94 nm, located in the ultraviolet region. Natural Bond Orbital (NBO) analysis has been performed on MMH + AB −2 compound to analyze the stability of the molecule arising from hyperconjugative interactions and charge delocalization. The highest stabilization energy, calculated to be 173.12 kcal/mol, is for the interaction between the lone pair on the N11 atom and the antibonding orbital of the C5 atom and 124.34 kcal/mol is for the interaction between the lone pair on the N3 atom and the antibonding orbital of the C5 atom. Molecular Electrostatic Potential (MEP) has been performed by DFT -B3LYP/6-311+G (d, p) basis set and the total electron density of the molecule ranges from -7.529 × 10 –2 to + 7.529 × 10 –2 e.s.u.. Dielectric studies further supported its suitability for electronic applications by highlighting its dielectric constant and loss factor. Electrical conductivity tests demonstrated the compound's potential as a semiconductor material. Additionally, the crystal packing behavior of MMH + AB −2 was analyzed statistically using Hirshfeld Surface Analysis and the molecular packing of the crystal strongly depends on H–H hydrogen bond interactions, which account for 39.8% of all intermolecular interactions in the studied system. The computed first order hyperpolarizability β tot  = 377.570 × 10 −31  e,s.u reveals that the present compound MMH + AB −2 has SHG efficiency 101.25 times of Urea and 55.11 times that of KDP.

We report here a checklist of tintinnids (loricate ciliates) for the coastal zone of India. Based on available literature (1978 to 2017), a total of 25 stations were studied from 5 distinct areas of Indian coastal waters. A total of 151 species of 33 genera belonging to 14 families of tintinnids were documented. Diversity patterns of tintinnids were recorded higher along the west coast (30 genera and 106 species) than the east coast of India (20 genera and 93 species). Among tintinnids families, the Codonellidae (2 genera and 52 species, 20%) and the Tintinnidae (8 genera and 21 species, 19%) are the major contributors to the total tintinnids diversity in the Indian coastal zone.

The aim of this work was to investigate the structure, optical and magnetic properties of bismuth-doped cobalt ferrite nanoparticles (Co Bi x Fe 2 O 4 , x = 0, 0.05, 0.10) prepared by the sol-gel technique. X-ray diffraction indicated that the prepared samples were cubic spinel with space group Fd 3 m . The crystallite size, lattice parameter, and unit cell volume decreased with increasing bismuth ion content, which was explained by the difference in ionic radii. Magnetic measurements at room temperature using a vibrating-sample magnetometer showed a decrease in saturation magnetization, remanent magnetization, and coercive field from 76.92, 41.84 emu/g, 288.79 Oe to 34.62, 18.43 emu/g, 186.58 Oe, respectively, as the concentration decreased from x = 0 to 0.10. Spectroscopic measurements in the UV–visible region confirmed that the band gap increased from 2.252 to 2.321 eV as x increased from 0 to 0.10. The prepared samples were a semiconductor magnetic material and were used in a high magneto-optic recording device.

MOXIE is a technology demonstration that addresses the Mars 2020 (Perseverance) objective of preparing for future human exploration by demonstrating In Situ Resource Utilization (ISRU) in the form of dissociating atmospheric CO 2 into O 2 . The primary goals of the MOXIE project are to verify and validate the technology of Mars ISRU as a springboard for the future, and to establish achievable performance requirements and design approaches that will lead to a full-scale ISRU system based on MOXIE technology. MOXIE has three top-level requirements: to be capable of producing at least 6 g/hr of oxygen in the context of the Mars 2020 mission (assuming atmospheric intake at 5 Torr, typical of Jezero Crater, and 0 ∘ C , typical of the rover interior); to produce oxygen with > 98 % purity; and to meet these first two requirements for at least 10 operational cycles after delivery. Since MOXIE is expected to operate in all seasons and at all times of day and night on Mars, these requirements are intended to be satisfied under worst-case environmental conditions, including during a dust storm, if possible.

In this study, we reported the synthesis of pure ZnO and Mg-doped ZnO (Mg-ZnO) nanoparticles by simple co-precipitation method and studied the ethanol sensing activity of the synthesized nanostructures. XRD analysis illustrates that the synthesized ZnO and Mg-doped ZnO nanoparticles (NPs) possess hexagonal wurtzite structure and the average crystallite size is calculated to be 29 nm and 33 nm, respectively. The FT-IR spectra of pure and Mg-doped ZnO NPs confirm that the presence of bands appeared near 400 cm-1 for Zn-O and the bands at 622 cm-1 can be attributed to Mg-O stretching modes. The band gap energy estimated from the absorption spectra for ZnO and Mg-ZnO NPs, respectively, at 3.26 eV and 3.32 eV, displays the considerable optical property. Further, we observed that the UV-Vis spectroscopic data exhibits high absorbance in the UV range for the prepared samples. The SEM images clearly display the needle-like morphology of the synthesized samples. Dynamic light scattering analysis shows average particle size of 110 nm. The ethanol sensing measurements were carried out with 100 ppm concentration, and the linear responses from ZnO and Mg-ZnO NPs-based sensors are detected in the working temperature of 350°C. The obtained results demonstrated that the synthesized Mg-ZnO nanostructures have improved conductivity with larger active surface area for the most promising application in the ethanol sensing activity.