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By tailoring and optimizing the structure of core or shell material, complete alteration of properties of the material can be obtained. Herein, we have reported synthesis of CaCu3Ti4O12@CoFe2O4particles through the chemical co-precipitation route. CaCu3Ti4O12@CoFe2O4particles consist of CaCu3Ti4O12(~ 200 nm) as a core and CoFe2O4as a shell of 2.5 nm. The prepared composites are characterized with appropriate characterization tools. The morphological results confirm the proper formation of core shell structure where CaCu3Ti4O12and CoFe2O4act as a core and shell, respectively. The greater CCTO content composites exhibited promising relative permittivity of 8.2 × 103at 700 °C sintering temperature (8 h) at frequency 40 to 8 MHz. When CaCu3Ti4O12@CoFe2O4undergoes heat treatment, it leads to the removal of oxalic acid. However, a weight loss of 8.3% is obtained for CCTO-coated composites that is quite low as compared to ~ 11% weight loss obtained in pristine CFO. The removal of organic groups significantly contributed to the increase in dielectric properties. These results imply that the development of CaCu3Ti4O12@CoFe2O4core shell structure paves the wave for high-performance devices.

This work presents a comprehensive study on the dielectric properties of shellac-based composites with varying filler concentrations of (SiC) and iron (Fe) particles, complemented by scanning electron microscopy (SEM) analysis. Shellac, a natural biopolymer known for its excellent film-forming abilities, biodegradability, and insulating properties, was chosen as the matrix material. The dielectric properties, including permittivity and dielectric loss, are measured by LCR Meter across a frequency range from 100 Hz to 8 MHz to evaluate the effects of filler concentration. This study reveals that the incorporation of SiC and Fe particles significantly enhances the dielectric constant and exhibits complex frequency-dependent behavior in dielectric loss. SEM analysis provided insights into the microstructural changes induced by the fillers, correlating with the observed dielectric properties. The results indicate that the dielectric performance of shellac composites can be effectively tailored through the precise control of SiC and Fe particle concentrations, attributed to interfacial polarization and Maxwell-Wagner-sillars effects. This work underscores the potential of shellac composites as sustainable, high performance dielectric materials for advanced electronic applications, contributing to the development of eco-friendly electronic devices.

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Purpose: The study aims to investigate the propagation of inhomogeneous waves in a material with triple porosity. Methods: The mathematical equations describing the motion of harmonic plane waves in a material with triple porosity have been solved. The solution is derived as Christoffel equations. The propagation of plane harmonic waves may be explained through two equations, which are obtained by solving the Christoffel equations. One of them provides the velocity of longitudinal waves. The other provides a lone shear wave in triple-porosity medium. A general inhomogeneous propagation is considered through a particular specification of complex slowness vector for any of these five attenuated waves. The inhomogeneity of an attenuated wave is represented through a finite non-dimensional parameter. The specification of a wave's slowness vector is utilized to compute its phase velocity and attenuation for an arbitrary value of this inhomogeneity parameter. Results: The numerical example is considered to compute the propagation characteristics (velocity, attenuation) of each of the five inhomogeneous waves in the triple-porosity medium. The impact of various factors, such as hydrate gas saturation, wave-induced fluid flow, solid Poisson ratio, inhomogeneity parameter, frequency, porosity, critical porosity, depth, and coordination number is investigated on the phase velocities and attenuations of the five waves mentioned above. Conclusions: The findings reveal that these waves' phase velocities and attenuation coefficients are more sensitive to gas hydrate saturation and frequency than other factors.

ABSTRACTNumerical model of a wideband band reject filter using closed rectangular loop resonator is presented using transmission lines. The prototype design of wide band reject filter centred at 3 GHz with lower cut-off frequency of 2 GHz and upper cut-off frequency of 4 GHz is fabricate from the optimal values obtained from the numeric model on a substrate (FR4) with a dielectric constant of 4.3, loss tangent of 0.02–0.03 and substrate height of 1.6mm. For bidirectional operations, the length-to-width ratio of filter is 2:1. The impedance of the transmission line which is connected between input and output ports is taken as double the feed line impedance while the impedance of the other half wavelength is considered as four times the feed line impedance. The design has obtained bandwidth of more than 60%. It is observed that the full wave electromagnetic results are in good agreement with the experimental and numerical results.

It is desirable to exploit biomass energy along with coal and petcoke through gasification, and understanding the differences between petroleum coke (petcoke), coal and biomass gasification behaviour becomes very essential. Consequently, present investigation compares gasification components of petcoke, sawdust and high ash coal with their physico-chemical properties under isothermal conditions in CO2atmosphere in the temperature range of 1173–1623 K. Physico-chemical characterisation includes proximate and ultimate analyses, porous structure analysis by Brunauer-Emmett-Teller (BET) surface area from nitrogen (N2) adsorption isotherm, ash composition analysis and ash fusion temperature. The effects of temperature and nature of different solid fuels on gasification reactivity have been discussed. Gasification kinetics has been investigated using two nth-order kinetic models, such as homogeneous model (HM) and shrinking core model (SCM). Influence of diffusion resistance on gasification behaviour of different solid fuels is also reported. Thus, the present study will be helpful to realise the effects of high ash in gasification behaviour as well as in designing and modelling of the suitable gasifier and to establish optimum gasification conditions for petcoke, biomass and high ash coal.

In this study, a total of 118 genotypes, including 90 wild accessions belonging to AA genome (O. glaberrima, O. barthii, O. nivara, O. rufipogon, O. longistaminata, O. meridionalis, O. glumaepatula) and CC genome (O. officinalis), 19 non-basmati genotypes and nine basmati cultivars were analyzed for their protein content and grain characteristics in brown rice. The protein content in wild rice accessions was appreciably high as 20.8% followed by non-basmati and (11.5%) and basmati (11%) cultivars. Thousand-grain weight and grain breadth (GB) were highest in wild rice accessions (30.4gm and 2.9 mm), while grain length and L: B were highest in basmati cultivars (8.9 mm and 6.2). Fractionation of storage proteins and SDS gel electrophoresis revealed that significant differences in the protein content between the wild rice species and cultivated rice genotypes were mainly due to differences in their glutelin contents and high molecular weight glutelin polypeptides. The presence of characteristic bands in selected accessions is a useful parameter for identification of rice germplasm. The wild species that had high protein content has potential to increase the nutritional quality of rice through interspecific crosses in future breeding programs.

BackgroundWe examined the associations between the 6-year incidence of age-related macular degeneration (AMD) and vision-related quality of life (VRQoL), and the contribution of presenting visual acuity (VA), in an Asian population.MethodsFundus images from the Singapore Chinese Eye Study, a population-based cohort study (baseline: 2009–2011; follow-up: 2015–2017), were graded using a modified Wisconsin age-related maculopathy grading system. Incident AMD was defined as no baseline AMD in both eyes and early/late AMD in the worse eye at follow-up. Presenting VA was assessed using the logarithm of the minimum angle of resolution chart at 4 m under standard lighting conditions with habitual correction. Multiple linear regression models determined the associations between AMD incidence with changes in the Rasch-transformed scores of the Reading, Mobility and Emotional VRQoL domains of the 32-item Impact of Visual Impairment (IVI-32) questionnaire, adjusted for traditional confounders. The contribution of presenting VA to changes in VRQoL was also estimated.ResultsOf the 2251 participants without AMD at baseline (mean age (SD): 57.7 (9) years, 51.4% women), 101 (4.5%) and 11 (0.5%) developed incident early and late AMD at follow-up, respectively. Incident late AMD was associated with significant 30.3%, 32.5% and 30.9% decrements in Reading, Mobility and Emotional IVI scores, respectively. The contribution of presenting VA ranged between 1.62% and 4.35% of the observed decrements. No significant associations were noted with incident early AMD.ConclusionIncident late AMD had a substantial impact on all aspects of VRQoL, with presenting VA contributing only minimally to this longitudinal relationship.

Our study compared the diagnostic accuracy of the 10% alcohol–formalin cell-block (CB) technique against traditional smears (CS) in serous effusions over 1 year. CB outperformed CS by detecting 7 missed cases and diagnosing 177 benign, 5 suspicious and 26 malignant cases compared to CS's 180 benign, 9 suspicious and 19 malignant cases. Using histopathology as a gold standard, CB showed a sensitivity of 96.4%, specificity of 98.3% and diagnostic accuracy of 98.1%, significantly higher than CS's 79.3% sensitivity, specificity of 97.7% and 95.2% accuracy. Using a 10% alcohol–formalin method, CB also excelled in cytomorphological characterization, especially in background elements, cellularity and cellular architecture. CB offered improved diagnostic accuracy and allowed extra sections for additional tests. In resource-constrained settings, combining CS and CB enhances cytological assessment.

This paper presents research work about the design and fabrication of a 44-layer optical reflective notch filter. The performance of the fabricated notch filter was studied at normal (0°) and oblique (45°) incidence angle. In addition, the paper also discusses a three-layer broadband antireflective coating on both sides of the multilayer stack to suppress the ripples in the passband region. The thickness-modulated reflective stack of the filter was designed by using the materials ${{\rm Al}_2}{{\rm O}_3}$Al_2O_3 (1.63) and ${{\rm SiO}_2}$SiO_2 (1.46). Optimization of the multilayer stack was carried out by using the damped least-squares algorithm. The theoretical and experimental results from the ion-assisted e-beam deposited samples for single notch reflective filters are presented. Good agreement in the design and experimental results was observed when the deposition process was controlled by time of evaporation. Further, the filter was characterized for the optical properties by using a UV-VIS-NIR spectrophotometer, surface morphology and protective properties using field emission scanning electron microscopy, a coherence correlation interferometer, and water contact angle.

The aim of our case–control study was to determine expression of VEGFA mRNA in placentae of preeclamsia (PE) versus uncomplicated pregnancy to further clarify its differential expression in pregnancy hypertensive disorders. The PE group was subdivided into severe and non-severe; those with or without HELLP syndrome and placental VEGFA characteristics were compared for these cohorts. Additionally, the neonatal and maternal outcomes were recorded. The quantification of placental VEGFA was done using quantitative real-time PCR and results were expressed as fold change. Out of 42 PE cases, 23 (55%) were non-severe and 19 cases (45%) were severe PE. Out of 19 severe PE patients, 8 (42%) were HELLP syndrome (complete HELLP) and remaining 11 (58%) were non-HELLP severe PE. Compared to controls, the true fold change in PE, HELLP, non-HELLP, severe PE, non-severe PE was − 2.186, − 13.333, − 6.698, − 8.950 and 1.466, respectively. Our results showed a lowered VEGFA expression in PE placentae compared to uncomplicated controls. The finding of initial increase of VEGFA in non-severe PE and subsequent marked lowering in HELLP strengthens the existing hypothesis of decompensated VEGF being a major role player in PE.

AimsDiabetes is a major public health problem in migrants and ethnic minorities worldwide. We determined the incidence and risk factors of diabetic retinopathy (DR) in migrant Indians living in Singapore.MethodsWe included data from 759 Indian adults with diabetes, who participated in the baseline (aged 40–80 years, 2007–2009) and 6-year follow-up 2012–2015 of the Singapore Indian Eye Study. Retinal photographs were graded for the presence and severity of DR using modified Airlie House Classification. Incidence was assessed in participants who were free of DR at baseline visit (n=501), while progression in those with DR but free of proliferative DR at baseline visit (n=189). Risk factors included demographic, lifestyle, socioeconomic, family history, genes, duration of diabetes, glycaemic control, insulin use, ocular and clinical factors.ResultsThe 6-year age-standardised DR incidence and progression were 21.89% and 33.45%, respectively. HbA1c (risk ratio (RR) 1.41, 95% CI 1.28 to 1.55 per unit increase), current smoking (RR 1.63, 95% CI 1.02 to 2.62) and insulin use (RR 2.63, 95% CI 1.44 to 4.82) were associated with higher incidence, whereas estimated cerebrospinal fluid pressure (RR 0.90, 95% CI 0.82 to 0.98) and body mass index (BMI) (RR 0.74, 95% CI 0.60 to 0.93) were associated with lower incidence of DR. Higher HbA1c (RR 1.26, 95% CI 1.13 to 1.42), BMI (RR 1.26, 95% CI 1.02 to 1.56) and estimated cerebrospinal fluid pressure (RR 1.11, 95% CI 1.02 to 1.21) were associated with DR progression. The population attributable risk of HbA1c >8% was 41.29% and 49.63% for DR incidence and progression.ConclusionDR incidence and progression in migrant Indians living in Singapore was more than double that reported in Indians living in urban India. Consistent with past studies, poor glycaemic control was an important predictor for incidence and progression of DR.

Background/aimsTo assess the independent impact of diabetic retinopathy (DR) on three domains of vision-related quality of life (VRQoL) in a Chinese Singapore population.MethodsThe Singapore Chinese Eye Study (n=3353; 2009–2011) was a population-based, prospective, cross-sectional study conducted at the Singapore Eye Research Institute. The study population included 292 adults with diabetes, with and without DR. DR (better eye) was categorised as presence and absence of any DR; severity of DR (no vision-threatening DR (VTDR); severe non-proliferative DR (NPDR); PDR and/or clinically significant macular oedema and VTDR). Our main outcome was VRQoL which was measured using Rasch-calibrated scores from the ‘Reading’, ‘Mobility’ and ‘Emotional’ domains of the Impact of Vision Impairment questionnaire. The relationship between DR and VRQoL was assessed using multiple linear regression models.ResultsOf the 292 individuals (mean age 61.35 ± 9.66 years; 55.8% male), 201 (68.8%), 49 (16.8%), 20 (6.8%), 22 (7.5%) and 27 (9.2%) had no DR, minimal-mild NPDR, moderate-severe NPDR, PDR and VTDR, respectively. Any DR and VTDR were independently associated with 6% and 12% worse Reading scores and 7% and 18% poorer Emotional well-being, respectively, compared with those without DR. These associations persisted after separate adjustment for visual impairment and presenting visual acuity. No significant difference was found in the Mobility domain between persons with and without DR.ConclusionsWe documented that DR, particularly VTDR, was independently associated with restrictions in Reading and Emotional well-being. Understanding factors underlying the detrimental DR-VRQoL relationship may optimise rehabilitation outcomes for individuals with DR.

A design technique for multiple stop band graded index filters is proposed in this paper using quintic apodization function and by superimposing refractive index profiles optimized for different wavelengths in visible portion of electromagnetic spectrum (400, 500 and 600 nm). The optical performance of the filters is simulated using the Filmstar™ design software for double and triple stop band filters. The results are compared for constant and varying peak-to-peak refractive index. The aim of this work is to attain equal reflectance values at all desired wavelengths (~85%). The results show that reflectance performance for equal peak amplitude for double band and triple band filters is obtained as ~86 and 83%, respectively for each stop band wavelengths when peak-to-peak refractive index is varied.

•Characteristic cool white light emanating Ba5Zn4Gd8O21: Dy3+ nanophosphors are fabricated for first time via urea assisted solution combustion method.•Crystal structure and phase purity investigations is made by Rietveld Refinement Technique.•Decay lifetime, quantum efficiency, non-radiative rates and energy bang gap of the Dy3+ activated nanocrystals have been calculated effectively.•CIE coordinates, color purity and CCT values certify their cool white light emitting property thus proves them a potential agent for solid state lighting, display and laser devices.

Abstract: Dynamic light scattering (DLS) studies were carried out to investigate the aggregation behavior of 1.1M solutions of tributyl phosphate (TBP), N,N-dihexyl octanamide (DHOA) and of N,N-dihexyl decanamide (DHDA) in n-dodecane equilibrated with varying concentrations of nitric acid (0.1–6M) and of Th (10–200g/L). There was a gradual increase in thorium extraction with increased aqueous phase acidities. A significant enhancement in the aggregate sizes was observed with increasing concentration of thorium in the organic phase. The effect of 1-octanol as phase modifier was also investigated on the aggregation behavior of extracted species for TBP system. [Copyright &y& Elsevier]

Distribution studies on Th(IV), Pa(V), U(VI) and Pu(IV) were carried out employing tri-n- butyl phosphate (TBP) and N,N-dihexyl octanamide (DHOA) as extractants under proposed advanced heavy water reactor (AHWR) spent fuel feed conditions. DHOA was found promising for selective extraction of U/Pu over Pa and Th as compared to TBP. Both Pu and Th formed trisolvated species with DHOA at 4 M HNO3. Batch solvent extraction experiments were carried out for selective extraction of U and Pu from simulated AHWR spent fuel dissolver solution using 0.36 M DHOA and 0.18 M TBP dissolved in n-dodecane as solvents. Quantitative extraction of uranium and plutonium was achieved under experimental conditions leaving bulk of thorium in the raffinate. The co-extracted thorium from the organic phase was proposed to be scrubbed using 4 M HNO3. A series of non-salt forming reductants were evaluated for their suitability for the partitioning of plutonium. Uranium from the Pu lean organic phase was proposed to be stripped using 0.01M HNO3. The extraction behavior of fission products was also examined under the simulated AHWR spent fuel feed solution. Based on these observations, a reprocessing scheme has been proposed for the reprocessing of three component U, Pu and Th system arising out of the irradiated (Th, Pu)O2pins.

Solvent extraction studies carried out at BARC, India on the evaluation of N,N-dialkyl amides as alternative extractants to tri-n-butyl phosphate (TBP) for reprocessing of spent fuel have suggested that straight chain N,N-dihexyloctanamide (DHOA) is promising alternative to TBP for the reprocessing of irradiated uranium based fuels. This paper presents the batch as well as mixer settler studies for uranium and plutonium extraction/stripping to evaluate DHOA visa-vis TBP for the reprocessing of Pu rich fuels. These studies showed that uranium extraction using DHOA as extractant was comparable to that of TBP; however, it displayed better stripping behavior than TBP. Plutonium extraction behavior was better in the case of DHOA as compared to that of TBP. However, Pu stripping data indicated towards the need of reducing agent in the stripping cycle for both the extractants.

Conditions have been optimized for selective removal of protactinium by solvent extraction from short-cooled spent fuel dissolver solution and from high-level waste solution under simulated conditions employing diisobutyl carbinol (DIBC) as extractant. These studies include: effect of acidity, extractant and thorium concentration on the extraction behavior of protactinium. Selectivity of the extractant for protactinium has been investigated with respect to U, Pu, Th, and the fission/activation products. These studies suggest that 40% DIBC (~2.02 M) solution in n-dodecane can be employed for the recovery of protactinium from short-cooled spent fuel dissolver solution and from high-level waste solutions. Extraction of Pa increased with aqueous phase acidity due to the formation of protonated species of DIBC, [H(DIBC)1-2]+and anionic Pa(OH)2(NO3)4]-species. There was an enhancement in Pa extraction at lower acidities (<4 M HNO3) with increased Th concentration (up to 200 g/l) beyond which a decrease was observed. At 200 g/l Th in 4 M HNO3, the separation factor (SF) values of Pa over U and Th are ~100, >105, respectively. DIBC displays good fission/activation product decontamination under the conditions of these studies.

ABSTRACTDistribution studies on Th(IV), Pa(V), U(VI) and Pu(IV) were carried out employing tri-nbutyl phosphate (TBP) and N,N-dihexyl octanamide (DHOA) as extractants under proposed advanced heavy water reactor (AHWR) spent fuel feed conditions. DHOA was found promising for selective extraction of U/Pu over Pa and Th as compared to TBP. Both Pu and Th formed trisolvated species with DHOA at 4 M HNO3. Batch solvent extraction experiments were carried out for selective extraction of U and Pu from simulated AHWR spent fuel dissolver solution using 0.36 M DHOA and 0.18 M TBP dissolved in n-dodecane as solvents. Quantitative extraction of uranium and plutonium was achieved under experimental conditions leaving bulk of thorium in the raffinate. The co-extracted thorium from the organic phase was proposed to be scrubbed using 4 M HNO3. A series of non-salt forming reductants were evaluated for their suitability for the partitioning of plutonium. Uranium from the Pu lean organic phase was proposed to be stripped using 0.01M HNO3. The extraction behavior of fission products was also examined under the simulated AHWR spent fuel feed solution. Based on these observations, a reprocessing scheme has been proposed for the reprocessing of three component U, Pu and Th system arising out of the irradiated (Th, Pu)O2pins.

ABSTRACTSolvent extraction studies carried out at BARC, India on the evaluation of N,N-dialkyl amides as alternative extractants to tri-n-butyl phosphate (TBP) for reprocessing of spent fuel have suggested that straight chain N,N-dihexyloctanamide (DHOA) is promising alternative to TBP for the reprocessing of irradiated uranium based fuels. This paper presents the batch as well as mixer settler studies for uranium and plutonium extraction/stripping to evaluate DHOA vis a-vis TBP for the reprocessing of Pu rich fuels. These studies showed that uranium extraction using DHOA as extractant was comparable to that of TBP; however, it displayed better stripping behavior than TBP. Plutonium extraction behavior was better in the case of DHOA as compared to that of TBP. However, Pu stripping data indicated towards the need of reducing agent in the stripping cycle for both the extractants.

ABSTRACTConditions have been optimized for selective removal of protactinium by solvent extraction from short-cooled spent fuel dissolver solution and from high-level waste solution under simulated conditions employing diisobutyl carbinol (DIBC) as extractant. These studies include: effect of acidity, extractant and thorium concentration on the extraction behavior of protactinium. Selectivity of the extractant for protactinium has been investigated with respect to U, Pu, Th, and the fission/activation products. These studies suggest that 40% DIBC (∼2.02 M) solution in n-dodecane can be employed for the recovery of protactinium from short-cooled spent fuel dissolver solution and from high-level waste solutions. Extraction of Pa increased with aqueous phase acidity due to the formation of protonated species of DIBC, [H(DIBC)1−2]+and anionic Pa(OH)2(NO3)4]–species. There was an enhancement in Pa extraction at lower acidities (⩽4 M HNO3) with increased Th concentration (up to 200 g/l) beyond which a decrease was observed. At 200 g/l Th in 4 M HNO3, the separation factor (SF) values of Pa over U and Th are ∼100, >105, respectively. DIBC displays good fission/activation product decontamination under the conditions of these studies.

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