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In-situ reduction of plutonium and uranium for the separation of U/Pu is suitable for pl utoniumrich fuels such as FBR fuels. The mathematical basis for a computer program PUSEP (Plutonium Uranium Solvent Extraction Program) for the analysis of partitioning cycle of PUREX process involving in-situ electrochemical reduction of uranium and plutonium is described in the present investigation. Model equations have been developed on the basis of the idealized model for mixer settlers incorporating distribution coefficients and redox reactions of the species involved and solved numerically to obtain concentration profiles of components. The validity of the model equations and associated computer program is tested by carrying out experiments in a proto type 20-stage electrolytic ejector mixer-settler operating without diaphragm for the electro reduction of uranium. The stage-wise experimental concentration profiles of U(VI), U(IV) and nitric acid were obtained and compared with the theoretical predictions. A reasonably good agreement is achieved between experimental and predicted concentration profiles. [ABSTRACT FROM AUTHOR]

Ternary nanocomposites, including graphene oxide (GO), hydroxyapatite (HAP), and cadmium selenite (CdSe) have been encapsulated into nanofibrous scaffolds of polylactic acid. These compositions were indexed as HAP@PLA (C1), CdSe@PLA (C2), HAP/CdSe@PLA (C3), HAP/GO@PLA (C4), and HAP/CdSe/GO@PLA (C5). Structural confirmation is executed by XRD and XPS techniques, while FESEM performs morphological characteristics. CdSe and GO dopants cause a significant increase in nanofiber diameter, HAP/GO@PLA (C4), showing thin surface fibers with fiber diameter up to 3.1 μm, followed by HAP/CdSe/GO@PLA (C4) composite that belongs to filament size up to 2.1 μm. On the other hand, the mechanical properties reveal that the dual dopant composites HAP/CdSe@PLA (C3) and HAP/GO@PLA (C4) hit the maximum tensile fracture values with 1.49 ± 0.3 and 0.99 ± 0.2 MPa. Further, the ternary C5 composite represents the lowest contact angle of 86.1 ± 3.7°. The antibacterial activity increased from 32.4 ± 9.7 and 28.4 ± 6.5% to be 85.3 ± 4.6 and 88.1 ± 5.6% for C1 and C5, respectively, against both E. coli and S. aureus in dark conditions. Moreover, the antibacterial potency enhanced from 75.4 ± 7.6 to be 83.5 ± 6.5 from dark to light conditions against E. coli for the composition of PLA containing the binary composition of HAP/CdSe. [Display omitted] • Nanocomposites of hydroxyapatite, graphene oxide, and CdSe have been incorporated into electrospun polylactic acid (PLA). • The average roughness has increased significantly from 71 to 158 nm for HAP, and the ternary HAP/CdSe/GO into PLA. • The antibacterial increased from 32.4±9.7 % to 85.3±4.6 % for C1 and C5, against E. coli and S. aureus in dark conditions. • The antibacterial potency enhanced from 75.4±7.6 to be 83.5±6.5 from dark to light conditions against E. coli. [ABSTRACT FROM AUTHOR]

• Vanadate ions have been incorporated into hydroxyapatite (HAP) lattice with different concentrations using the co-precipitation technique. • Vanadate dopants cause a considerable effect on lattice parameters whereas the a-axis expands from 9.483 Å to 9.602 Å, while c-axis plunges from 6.916 Å to 6.853 Å for x = 0.0 and 0.6, respectively. • The average roughness increased with vanadate concentration from 30.3 nm and achieved around 53.8 nm for the lowest and the highest additional vanadate. • The cell viability was enhanced for V-HAP and reached its highest value of 99.4 %. • The highest vanadate concentration exhibited the highest antibacterial with inhibition zone of 10.4 and 9.5 mm against E. coli and S. aureus, respectively. Different contributions of vanadate ions have been incorporated into hydroxyapatite (HAP) lattice with different concentrations using the co-precipitation technique. Vanadate ions have introduced a structural change of the HAP formula to be as: [Ca 10 (PO 4) 6-x (VO 4) x (OH) 2 ]; whereas 0.0≤x≤1.2. Vanadate dopants have a considerable effect on lattice parameters, whereas the a-axis starts from 9.483 Å and expands to its maxima of 9.602 Å. However, the c-axis begins with 6.916 Å and plunges to 6.853 Å for x = 0.0 and 0.6, respectively. Moreover, the compositions showed higher thermal stability till x = 1.0; then, it declined sharply. The thermodynamic parameters accompanied by the thermal degradation process have been calculated using Coats–Redfern and Horowitz–Metzger methods. Both dehydration and decomposition kinetics show endothermic, non-spontaneous, and slow decomposition reactions. The cell viability was enhanced for V-HAP and reached its highest value of 99.4 %. The highest vanadate concentration, the more effective as antibacterial material, whose inhibition zone reaches its maximum values of 20.4 ± 1.5 and 19.5 ± 1.3 mm against E. coli and S. aureus respectively. Subsequently, these types of biomaterials could be suggested for potential clinical applications. [ABSTRACT FROM AUTHOR]

• Hydroxyapatite modified with different additional vanadium ions has been fabricated using a precipitation method. • Direct and indirect bandgaps achieved around 3.9 and 4 eV at x = 0.0 and decrease, reaching 3.82 and 3.94 eV at x = 1.2, respectively. • Methylene blue removal efficiency is rising with vanadate ions attained its max at x = 1.2 recorded 97.2% after 120 min of continuous exposure to visible light radiation. Degradation of pollutants, including organic dyes via photocatalysis technique, has attracted great concern last decade. Thus, modified hydroxyapatite (HAP) with vanadate ions (V O 4 3 − ) has been fabricated using the co-precipitation method at different vanadate contributions. The obtained compositions have been investigated upon their structure, morphology, and optical properties. The structural calculations indicated that a-axis increased from 9.483 to 9.562 Å for the lowest and the highest additional vanadate ions. Moreover, the average roughness developed from 30.5 to 56.3 nm upon the vanadate insertion. Moreover, the direct bandgap decreased from 3.9 to 3.82 eV upon the additional vanadate ions, while the refractive index increased slightly from 1.86 to 1.87. Further, the removal of methylene blue through aqueous solutions has been examined and showed that the removal effectiveness increased from 89.3 to 97.2% after 120 min of irradiation using visible light. These modified HAP crystals could encourage their utilization for potential applications incusing water treatment, besides their usages for biomedical applications. [ABSTRACT FROM AUTHOR]

• ZnO nanoparticles from organic salt was entrapped onto Bio-MOF. • Polyaniline was used to decorate the Bio-MOF. • Complete depletion of ciprofloxacin fluoroquinolone antibiotic under visible-light irradiation. • The prepared PAN/Bio-MOF was tested against different microbes. Conductive polymeric polyaniline (PAN) was encapsulated through biocompatible Bio-Metal-organic frameworks (MOF) containing Zinc oxide nanoparticles (ZnONPs) from organic salt. The prepared PAN@ZnONPs/MOF investigates the photocatalytic antimicrobial property and the depletion of ciprofloxacin (CIP) under visible-light irradiation. It was found that PAN has formed as fibrous network diameters 20 nm and a wide range of lengths, while pure MOF was like a rough rode shape with diameters about 55−130 nm. The surface roughness was promoted with the combination of PAN with MOF and the maximum height of the roughness achieved around 572 nm. The CIP depletion potential was studied to reach 97.2 % after 70 min under visible-light irradiation. The antimicrobial behavior exhibited better inhibition zone under light (18 ± 2.1 mm) compared to dark treatment (15 ± 0.9 mm) against tested microbes; S. aureus , E. coli , C. albican and A.niger. This indicates the highly prompted ability of MOF containing ZnONPs for disinfection and sterilization applications. [ABSTRACT FROM AUTHOR]

Due to its nutritional value, and taste, minced beef meat (MBM) is highly valuable therefore is susceptible to economically motivated adulteration. High-throughput adulteration detection methods are required to guarantee the authenticity and safety of the MBM. Hyperspectral imaging (HSI) in the 400–1000 nm spectral range, in tandem with multivariate analysis, was evaluated to demonstrate the feasibility of developing generic models to detect minced beef meat adulterated with other types of meats. Partial least squares regression (PLSR) method, the ensemble Monte Carlo variable selection method (EMCVS), a range of spectral pre-treatments, and combinations of any two of them were evaluated to predict the amount of MBM in each prepared sample scanned. The beef prediction model was developed using data from MBM adulterated with minced chicken and turkey meats and validated with data from MBM adulterated with pork meat at adulteration levels ranging from 0 to 51% at approximately 3% increments. Good prediction results were obtained using the EMCVS, on the asymmetric least squares (AsLs) + Standard Normal variate (SNV) pre-treated reflectance spectra (Rp2 0.96, RMSEP 2.9% and RPD 5.4) with 23 selected wavelengths. An independent set of MBM samples adulterated with lamb and duck meat were then prepared similarly at concentrations ranging from 3 to 21% to test the developed method. Good results were obtained in the full range (R2p 0.94, RMSEp 3.92%, RPDp 3.83) and excellent prediction results (R2p 0.95, RMSEp 2.78%, RPDp 5.29) were obtained with 9 optimum wavelengths (484, 508, 593, 596, 602, 736, 739, 924 and 960 nm). PLS discriminant analysis (PLS-DA), the EMCVS and spectral pre-treatments were used to discriminate MBM from other adulterants and achieved almost perfect classification for calibration, cross-validation, and prediction using 12 selected spectral bands. This study developed a high-throughput generic minced meat adulteration prediction and discrimination method based on selected spectral bands that can be used to further develop low-cost portable sensors for the digital sorting of adulterated MBM, and demonstrates the feasibility to develop generic models to detect minced beef meat adulterated with other types of meat. • A generic calibration model was developed for adulteration detection in minced beef. • Calibration performance improved after band selection. • Image processing algorithm was developed to show the level of adulteration. [ABSTRACT FROM AUTHOR]

The iron doped brushite (Fe-DCPD) nano particles were synthesized via co-precipitation method with Fe concentrations (0 ≤ x ≤ 1) in steps 0.2. The influence of iron concentration on the crystallinity, particle shape, morphology, optical, magnetic and electrical properties was investigated. The results showed that iron doping content is the crucial factor in the variation of physical properties. The particle shape changed from spheres at x = 0.2 to be fiber network at x = 0.8. The saturation magnetization (M s ) increased from 0.4 (emu/g) at x = 0.2 to 1.6 (emu/g) at x = 0.8 which is considered more than four times with a considerable decrease of coercive field. [ABSTRACT FROM AUTHOR]

[Display omitted] • Au@Se core–shell nanoparticles fabricated via laser ablation technique. • Au@Se core–shell nanoparticles incorporated into PCL nanofibrous scaffolds. • The surface roughness behavior heightened with SeNPs addition. • The antibacterial activity grows up reaching 8.3 ± 0.8, and 8.0 ± 0.8 for E. coli and S. aureus , respectively. • Au@Se@PCL polymeric blends could recommend in medical applications. Au@Se core–shell nanoparticles were obtained via laser ablation technique to be incorporated into polycaprolactone (PCL) nanofibrous scaffolds for wound healing applications at different contributions of Se nanoparticles (SeNPs). The synthesized layers were inspected via X-ray diffraction (XRD) and Fourier transformed infrared (FTIR). Additionally, microstructural and surface morphology were followed with different SeNPs contributions before and after fibroblast culturing. Moreover, Selenium dopant is affected Maximum roughness valley depth while it starts from 0.31 µm at Au@0.0Se@PCL reaching 0.457 µm at Au@12Se@PCL; however, after culturing starts from 0.3833 µm reaching 0.41 µm. Besides, the antibacterial activity was screened, showing the absence of inhibition zones in free selenium composition; however, it grows up reaching 8.3 ± 0.8, and 8.0 ± 0.8 for E. coli and S. aureus , respectively at the maximum contribution of selenium. SeNPs contributed composites show higher cell viability than Selenium free composite that it reaches its max in Au@8.0Se@PCL, recording 95.3 ± 2.3%. Composites show an excellent Wound dressing capability that its performance is directly proportional to selenium content. This significant enrichment of antibacterial activity and cell viability could recommend these composites for additional research in medical applications. [ABSTRACT FROM AUTHOR]

Polymer-based electrospun nanofibrous scaffolds containing polycaprolactone (PCL) were encapsulated with co-doped hydroxyapatite (HAP). The modification of HAP includes co-doped thallium (Tl+)/vanadate (V O 4 3 −) at different contributions of Tl+ ions. The obtained powdered and nanofibrous phases have been investigated upon their structure, morphology, and microstructure. The investigation of the surface morphology indicated that the scaffolds were formed in networked nanofibers with diameters around 0.2–0.8 μm to 43–80 nm for the lowest and the highest Tl ions contents through nanofibers. Besides, the maximum height of the roughness (R t) increased from 190.2 to 242.7 nm for the powdered compositions, while it started from 395.9 nm and increased to 861.0 nm for the nanofibers scaffolds. Furthermore, the mechanical properties were tested and showed that the toughness increased from 0.56 ± 0.11 to 2.52 ± 0.83 MJ/m3. The contact angle was measured and exhibited a decreasing behavior starting from 101.2 ± 2.5 to 87.6 ± 4.3°. In addition, the antibacterial potency was examined, and the inhibition zone increased up to 21.4 ± 1.1 and 20.4 ± 1.2 mm against E. coli and S. aureus , respectively. The in vitro culturing of human fibroblasts cell line through the scaffolds showed that the cells were spread and grew robustly upon the compositional variation. • Nanofibrous scaffold containing polycaprolactone (PCL) was encapsulated with co-doped hydroxyapatite (HAP). • The modification of HAP was carried out using co-doped thallium (Tl+)/vanadate (V O 4 3 −). • The surface morphology indicated that the scaffolds were formed in networked nanofibers. • The mechanical properties showed that the toughness was enhanced owing to the encapsulation and modification. • The antibacterial potency of nanofibrous scaffold was enhanced against E. coli and S. aureus. [ABSTRACT FROM AUTHOR]

Polymeric blends of carboxymethyl cellulose (CMC)/polyvinyl alcohol (PVA) doped with gold nanoparticles (AuNPs) were fabricated via casting technique, while the AuNPs were injected through the films by pulsed laser ablation technique. The obtained films were characterized using FTIR, FESEM besides optical and electrical investigations. The morphological features of the as-synthesized films show that compositions were formed as agglomerated grains with dimensions around 13.1–17.4, 8.7–12.6, 4.8–6.8, 13.5–23.2 and 5.8–9.7 μm, while AuNPs were shown as rod shapes with dimensions 1.2 × 0.19 μm for length and diameter. The maximum height of the roughness (R t) showed elevated values upon the additional AuNPs starting from 162.4 nm reaching to 345.1 nm for the lowest and highest contributions of AuNPs. Moreover, the direct-bandgaps were reduced with rising of AuNPs contribution starting from 5.08 to 4.88 eV. The applied electric field induced a formation of space charge polarization through the fabricated films correlated with the modification with AuNPs. Hence, compositional changes of bio-polymeric films provoke a great improvement for optoelectrical behaviors accompanied with morphological features. • CMC/PVA/AuNPs film well prepared by using casting process. • UV–visible showed the appearing of SPR absorption peak of the embedded AuNPs. • Both ε′ and ε'' values were increased with increase the laser ablation time. • Electrical conductivity approve CMC/PVA/AuNPs for electrical applications. [ABSTRACT FROM AUTHOR]

• AuNPs were synthesized from carboxymethyl cellulose and showed an extensive absorption peak at 528 nm. • Antioxidant was examined and the maximum trapping capacity (241.1 ± 13.22 mg/g) was reached at AuNPs content of 106.25 mg/ml. • The ratio of viable cells for AuNPs by HEK 293 T cell lines was reduced to 75.1 ± 3.8% at an approximated concentration of 500 μg / ml. • P. aeruginosa was the most susceptible bacterium to AuNPs with maximum inhibition zones of 50% whereas B. subtilis at 2 mg/l concentration of AuNPs. Gold nanoparticles (AuNPs) are widely used in the diagnosis and treatment of diseases owing to their environmental friendliness and controllability due to their compatibility and high potency in drug delivery. Here, AuNPs were prepared from carboxymethyl cellulose (CMC) and showed an extensive absorption peak at 528 nm owing to the characterized Plasmon Surface Resonance. TEM measurement affirms that the Au particles had spherical shapes accompanied by a uniform distribution and a size of approximately 12-20 nm. Otherwise, SEM images showed that the AuNPs were configured in agglomerated spherical shapes and the crystalline phase was evident from SAED images and spikes in the XRD model. Vigorous antioxidant was tested using the DPPH scavenger analysis and the produced maximum trapping capacity (241.1 ± 13.22 mg/g) was reached at an AuNPs content of 106.25 mg/mL. The ratio of viable cells for AuNPs by HEK 293 T cell lines was reduced to 75.1 ± 3.8% at an approximated concentration of 500 μg / mL. Besides, the antibacterial potency was examined after one day of exposure to (E. coli and P. aeruginosa) and (S. aureus and B. subtilis). AuNPs were toxic against all selected bacteria. P. aeruginosa was the most susceptible bacterium to AuNPs with maximum inhibition zones of 50% whereas B. subtilis at 2 mg/L concentration of AuNPs takes the lowest percentages of inhibition zone with 30% compared to 25% for antibiotic standard. These extraordinary behaviors of AuNPs exhibits the manipulation of nanoparticles is highly recommended for universal use in the treatment of skin and wounds. [ABSTRACT FROM AUTHOR]