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This paper proposes a state feedback output tracking Model Reference Adaptive Control (MRAC) to control the power of a nuclear reactor. A linearized version of nuclear reactor dynamics based on point kinetics modeling, with parameter uncertainties, is utilized for the control studies. Normalized negative gradient algorithm is used to update the controller gains adaptively. Stability of the closed loop system is established through Lyapunov analysis and Barbalet’s lemma. Performance of controller is validated through non linear simulation studies.

For the first time, a hybrid nanoparticle system of nanodiamond (ND) and cerium oxide (ceria) is used as a reinforcement material in order to enhance the γ-radiation stability of polysulfone (Psf) host membrane matrix. Control Psf and Psf–(ND + Ce) hybrid membranes are synthesized and characterized, with the loading of each nanomaterial varying from 0.25 to 0.5 wt%. The membranes are exposed to γ-radiation at different doses (up to 1000 kGy) and the effect of radiation on the Psf matrix is evaluated. Gel permeation chromatography studies confirm that the average molecular weight of the hybrid membranes is restored to a reasonable extent, in contrast to the control Psf membrane, which is reduced by 45% at a radiation dose of 1000 kGy. The optimum loading of ND and ceria in the membrane matrix is found to be 0.5% each, which offers a remarkable ∼10-fold enhancement of radiation stability compared to the control Psf membrane, making it a novel membrane material for potential applications in radioactive environments. The enhanced stability of the optimum hybrid membrane is due to the ability of ND and ceria in scavenging the secondary eaq− and OH˙ radicals, respectively, generated due to the radiolysis of water, as confirmed by the free radical scavenging studies.

We report, for the first time, the development of gamma radiation resistant polysulfone (Psf)-nanodiamond (ND) composite membranes with varying concentrations of NDs, ranging up to 2 wt% of Psf. Radiation stability of the synthesized membranes was tested up to a dose of 1000 kGy. To understand the structure-property correlationship of these membranes, multiple characterization techniques were used, including field-emission scanning electron microscopy, atomic force microscopy, drop shape analysis, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, gel permeation chromatography, positron annihilation spectroscopy, and small angle X-ray scattering. All the composite membranes exhibited enhanced radiation resistance properties, with 0.5% loading of NDs as the optimum. Compared to the radiation stability of Psf membranes up to a dose of 100 kGy, the optimum composite membranes are found to be stable up to a radiation dose of 500 kGy, owing to the unique surface chemistry of NDs and interfacial chemistry of Psf-ND composites. Experimental findings along with the Monte Carlo simulation studies confirmed a five times enhanced life-span of the composite membranes in an environment of the intermediate level radioactive waste, compared to the control Psf membrane.

Increased postprandial glucose (PPG) is associated with high glycated haemoglobin levels and is an independent risk factor for cardiovascular diseases. The aim of this study was to compare PPG increments in Asian versus non-Asian adults with type 2 diabetes (T2D), who were insulin-naïve or insulin-experienced, from the phase 3 insulin degludec/insulin aspart (IDegAsp) clinical trials.This was a post hoc analysis of data from 13 phase 3, randomised, parallel-group, open-label IDegAsp trials in patients with T2D. The pooled baseline clinical data were analysed for insulin-naïve and insulin-experienced groups; and each group was split into subgroups of Asian and non-Asian patients, respectively, and analysed accordingly. Baseline self-monitored blood glucose (SMBG) values at breakfast, lunch and the evening meal (before and 90 min after each meal) were used to assess PPG increments. The estimated differences in baseline SMBG increment between the Asian and non-Asian subgroups were analysed.Clinical data from 4750 participants (insulin-naïve, n = 1495; insulin-experienced, n = 3255) were evaluated. In the insulin-naïve group, the postprandial SMBG increment was significantly greater in the Asian versus the non-Asian subgroup at breakfast (estimated difference 28.67 mg/dL, 95% confidence interval [CI] 18.35, 38.99; p 0.0001), lunch (17.34 mg/dL, 95% CI 6.47, 28.21; p = 0.0018) and the evening meal (16.19 mg/dL, 95% CI 5.04, 27.34; p = 0.0045). In the insulin-experienced group, the postprandial SMBG increment was significantly greater in the Asian versus non-Asian subgroup at breakfast (estimated difference 13.81 mg/dL, 95% CI 9.19, 18.44; p 0.0001) and lunch (29.18 mg/dL, 95% CI 24.22, 34.14; p 0.0001), but not significantly different at the evening meal.In this post hoc analysis, baseline PPG increments were significantly greater in Asian participants with T2D than in their non-Asian counterparts at all mealtimes, with the exception of the evening meal in insulin-experienced participants. Asian adults with T2D may benefit from the use of regimens that control PPG excursions.NCT02762578, NCT01814137, NCT01513590, NCT01009580, NCT01713530, NCT02648217, NCT01045447, NCT01365507, NCT01045707, NCT01272193, NCT01059812, NCT01680341, NCT02906917.

The purpose of this study was to develop fast dissolving tablets of Aceclofenac using different concentration of super disintegrants. Fast dissolving tablets of Aceclofenac were prepared by dry granulation technique using croscarmellose sodium together with avicel ph as superdisintegrants. The porous granules were then compressed in to tablets by direct compression technique. These tablets were evaluated for drug content, weight variation, friability, hardness, wetting time and dispersion time. All the formulations showed low weight variation with dispersion time less than 90 seconds and rapid in vitro dissolution. The drug content of all the formulations was within the acceptable limits. The optimized formulation showed good release profile i.e. maximum drug being released at all-time intervals compared to other trial batches. It was concluded that fast dissolving tablets with improved dissolution could be prepared by dry granulation method of tablet. Keywords: Aceclofenac, fast dissolving tablet, dry granulation, super disintegrants.

This is the first study undertaken towards development of mixed-matrix membranes (MMMs) with enhanced radiation resistant attributes by reinforcement of nanostructured Gd2Zr2O7 (GZO) within polysulfone (Psf) host-matrix. The study describes synthesis and characterization of GZO in disordered, defect-fluorite structure, having average crystallite size of 31(±3) nm. Membranes prepared with different loading of GZO (up to 2 w/w% of Psf) are exposed to γ-radiation up to a dose of 1000 kGy in aqueous environment. The effect of radiation on the structural, mechanical, and thermo-oxidative properties of MMMs has been compared with that of radiation-sensitive Psf membrane. The ultrafiltration performance of the (un)irradiated Psf and MMMs reveal that an optimum reinforcement of GZO at 1 (w/wPsf)% offers ~10 times radiation resistant MMM, compared to that of Psf membrane. The MMM with 1 (w/wPsf)% GZO was rolled into 2512 spiral configuration and a highly-compact device was developed for treatment of radioactive effluent. Based on the flux decline behaviour over 18 months duration, the fouling behaviour of the MMM module was modelled. The life-span of the MMM was predicted based on the absorbed radiation dose, GZO leaching study, and fouling behaviour. It is proposed that GZO mitigates a fraction of the impinged γ-energy in swapping of the Gd3+ and Zr4+ sites, which protects the polymeric host-matrix in-situ from radiation induced degradation. The abundance of Gd3+ and Zr4+ associated with polar O2− over the impregnated GZO further stabilizes MMMs through scavenging of the oxidizing and reducing radiolysed products of water. Thus, we report a smart approach to develop novel MMM with greater life-expectancy against high-energy radiation and further fabricate a membrane-based device for management of liquid radioactive waste.

This paper proposes a machine vision scheme for denoising, feature space gradient preserving, and detecting weld defects in noisy weld X-radiography images; particularly, for the images that are in low-contrast and contain noises. The detection of small weld defects present on noisy image is extremely difficult in non-destructive testing through machine vision. The presence of high gradient magnitude and the low intensity in the feature space of a noisy image are the main characteristics of weld defects. These characteristics can be considered to refine and obtain noise-free images for detection of weld defects. This study proposes a modified anisotropic diffusion model, which considers a local probability value of gray-level and an adaptive threshold parameter in diffusion coefficient function to adjust the implication of low edge gradient of the feature space from the noisy image. Furthermore, an entropy based stopping criterion has been introduced to terminate the diffusion process. This proposed model is compared with the existing models, and its performance is evaluated through Mean Square Error (MSE), Signal-to-Noise Ratio (SNR), Peak Signal-to-Noise Ratio (PSNR), Entropy (E) and Mean Structural Similarity (MSSIM) measures. Experimental results confirm the reliability of the proposed model.

Nanomaterials potentially minimize the inherent trade-off between productivity and selectivity of membranebased ultrafiltration (UF) process. A comparative study on the reinforcement effect of pristine carbon nanotubes (CNTs) of three different configurations, viz. single-walled (SWNT), double-walled (DWNT) and multi-walled (MWNT), and their carboxylated counterparts, onto a polysulfone (Psf) host matrix of mixed-matrix UF membranes is illustrated herein. The varying structural features of carboxylated CNTs, probed by XPS analysis, underpin the enrichment of CNTs with oxygen rich functionalities following the trend of MWNT > DWNT > SWNT. The membranes with enhanced hydrophilicity and altered electrokinetics substantiate the efficacy of facilitated reinforcement of functionalized CNTs over the pristine ones. Variations in surface topography and mechanical feature of the membranes elucidate that carboxylation influences the interfacial chemistry by enhancing the dispersion stability of MWNTs more profoundly than its configurational counterparts like SWNTs and DWNTs, and concurrently alters its distribution within the membranous matrix. The enhanced ultrafiltration performances, as achieved by twofold enhancement in solvent fluxes without compromise in the solute rejection capabilities (~89–90% toward PEG, Mw: 35 kDa), confirm the potential of carboxylated CNTs in leading to development of high-performance mixed-matrix membranes.

HIx decomposition step of the Iodine-Sulphur (IS) thermochemical process for hydrogen production is the most critical step. The Coated Wall Membrane Reactor (CWMR) is an important configuration that can be used for carrying out HI decomposition. The present study uses Computational Fluid Dynamics (CFD) as a tool to assess the performance of a CWMR that ensures higher conversion for HI decomposition, which in turn positively affects the overall thermochemical efficiency of the IS process. The effects of various operating parameters, geometry and properties on conversion are studied. The results show that using a CWMR instead of a coated wall reactor (CWR) leads to significant process intensification by coupling reaction and separation in a single unit and enhancing conversion of the reaction. The operating parameters having significant impact on conversion are identified. Comparison of a CWMR with a Packed Bed Membrane Reactor (PBMR) shows that the PBMR gives higher conversion (at least 6%) than the CWMR for the entire range of parameters considered. For very low space velocity, high membrane permeability and low reactor diameters, conversions in PBMR and CWMR are almost the same.

A distinctive and impactful idea has been materialized to develop high-performance mixed-matrix ultrafiltration (UF) membranes using non-solvent induced phase inversion technique, utilizing various optimized compositions of polymer – polysulfone (Psf) and bactericidal nanostructured material, i.e., silver nanoparticles (Ag-nps). Membranes in sheet-configuration with high void volumes were synthesized employing large amount of polyvinyl pyrrolidone (PVP) as porogen. The resultant porous morphology and surface chemistry, i.e., surface hydrophilicity and electrokinetic features were assessed by instrumental techniques. The notable separation performances were observed as the membranes exhibited very high solvent throughput with reasonable anti-microbial activity. It has been substantiated that the nanoparticles upon impregnation within such a benign matrix of polymer exerted more pronounced mechanistic role towards anti-microbial efficacy on Escherichia coli, since as a survival mechanism the bacteria undergoing flagellar locomotory motion started experiencing negative chemotactic responses under the modified circumstances. With an objective of applying the salient features of such membranes, the facile methodical attempt was utilized in fabricating a domestic water purification device, with the membrane in candle-configuration for treatment of environmentally relevant aquatic media. It has been corroborated that our impactful approach towards development of an efficient water purification methodology (solvent throughput: 2500 LMH/bar and bacterial rejection: 99.99%) confirms the significance of membrane technology as a green and sustainable process with provision of easy scale up, energy and cost efficiency.

An algorithm that projects image intensity along a radial line oriented at a specific angle enables the recognition of vehicular license plates at odd angles. The algorithm determines orientation angle, rotates the image to a horizontal perspective, and removes image noise from rotation to achieve recognition accuracy as high as 98 percent.

Nanodiamond (ND) particles of different size (10, 250, and 500 nm) were used as filler materials for preparation of polysulfone-nanodiamond (Psf-ND) mixed-matrix membranes (MMMs), with loading of each ND particle varying from 0.1 to 2 wt% of polymer. Control Psf and MMMs were irradiated up to a γ-radiation dose of 1000 kGy. The effect of ND size was investigated on morphology, surface and mechanical properties, and performance of membranes in γ-radiation environment. The membranes were characterized by surface and cross-section SEM images, AFM, water contact angle studies, GPC, UTM, pure water permeability, and solute (PEO, 100 kDa) rejection measurements. The 10 nm sized ND enhanced the stability and performance of MMM up to 0.5% loading, while higher loading of it led to agglomeration of ND, and in-turn the deterioration of membrane performance. ND with larger particle size (250 and 500 nm), though dispersed homogeneously in the membrane matrix, but resulted in interfacial defects between ND and Psf host membrane matrix. The MMM with an optimum 0.5% loading of ND10 particles offered ~5 times enhanced radiation stability, as compared to that of control Psf membrane. This is the first of its kind study reported herein that provides an insight into the effect of ND particle size in altering the radiation resistance behaviour of MMMs.

License plate recognition is a computer vision method that identifies vehicles from their license plates. The most crucial step of such a system is accurate localization of the plate. The authors propose a system for automatic recognition that has three phases: image capture, plate localization, and license plate number recognition. They tested their methodology on 40 different car models with different types of license plates.

The salient features of a nanostructured carbonaceous material like graphene or graphene oxide have provided innovative alternatives for the development of nanocomposite membranes with better selectivity without having a compromise in throughput, which as a result have a promising role to play in desalination and water purification. Here, nanostructured reduced graphene oxide (nRGO) is synthesized from graphite powder and characterized. Using non-solvent induced phase inversion technique, a series of nanocomposite ultrafiltration (UF) membranes are developed by in situ impregnation of the as synthesized nRGO in polysulfone (Ps) polymer matrix with variation of nRGO from 1 to 8 w/w%. The physicochemical features and transport properties offered by the membranes are evaluated. Structural characterization of the Ps–nRGO composite UF membranes is done by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The variation in porous morphology of the membranes upon impregnation of nRGO is evaluated by scanning electron microscopy. Variation in skin surface topography is analyzed by atomic force microscopy. The change in surface hydrophilicity is evaluated by contact angle studies. The thermal and mechanical properties of the membranes are assessed by thermogravimetric analysis and tensile strength measurements, respectively. The studies reveal that an optimum loading of nRGO (2 w/w%) in the Ps matrix resulted in membranes with elimination of the trade-off between the flux and selectivity that exists with the conventional UF membranes. In addition, the optimum loading of nRGO resulted in membranes with improved thermal and mechanical stability. Thus, nRGO as an emerging potential nanofiller can lead to the development of an ideal membrane with desirable attributes.

Nanotechnology is a potential augmentation to the existing water purification technologies. Four different types of functional nanomaterials, like carbon nanotubes, metal/metal oxide nanoparticles, dendrimers and zeolites, are currently under evaluation for water purification application. Nanomaterials offer excellent opportunities because of high surface area (surface/ volume ratio), but the challenge is to build up an integrated scalable system. Membranes, because of being energy-economic and having the ability to get associated to different processes as a pretreatment or post-treatment stage, fi nd tremendous applications in the field of water purification. Nanostructured materials serve as a wonderful tool towards development of high flux, high selective membranes. Here attempts are made to develop biofouling resistant membrane. Nanoparticles of silver, copper and silver–copper mixture were impregnated on to the polysulfone host matrix and the biofouling resistance behavior of each membrane surface wa...

Anisotropic growth of ZnO nanorod arrays on ZnO thin films was achieved at a temperature of 90 degrees C by a surfactant-assisted soft chemical approach with control over size and orientation. ZnO thin films with c-axis preferred orientation had been achieved by the sol-gel technique. Lengths, diameters, and the degree of alignment of the ZnO nanorods were controlled by changing the experimental parameters. It was observed that the surfactant was essential to restrict the lateral growth of the nanorods, whereas the pH level of the reaction medium controlled the length of the nanorods. On the other hand, the orientation of the nanorods depended on the crystalline orientation of the film as well as the pH of the reaction medium. Room-temperature photoluminescence studies revealed that the ZnO nanorods with the best alignment exhibited the best emission property. The ZnO nanorods exhibited a strong UV emission peak at approximately 3.22 eV, ascribed to the band-edge emission. The field emission studies of the well-aligned nanorod arrays exhibited a low turn-on field of 1.7 V/microm to get an emission current density of 0.1 microA/cm(2).

CdS one-dimensional nanoforms such as nanowires, nanoribbons, network-like nanowires, pearl necklace type nanowires, helical-like nanowires, and nanowire arrays were formed on Si substrates by a simple thermal evaporation route. The shapes of the one-dimensional CdS nanoforms were controlled by varying the experimental parameters such as temperature and position of the substrates. Formation of the CdS one-dimensional nanoforms was initiated by the Au catalyzed vapor-liquid-solid technique, whereas the vapor-solid process played a crucial role in defining the shapes of the nanoforms. Different optical characterizations such as optical absorbance, photoluminescence, and Raman spectroscopy were adopted to explore the physical and structural quality of these CdS nanoforms.

Mixed-matrix membranes (MMMs) were developed by impregnating organofunctionalized nanoadditives within fouling-susceptible polysulfone matrix following the non-solvent induced phase separation (NIPS) method. The facile functionalization of nanoparticles of anatase TiO 2 (nano-TiO 2 ) by using two different organoligands, viz . Tiron and chromotropic acid, was carried out to obtain organofunctionalized nanoadditives, F T -nano-TiO 2 and F C -nano-TiO 2 , respectively. The structural features of nanoadditives were evaluated by X-ray diffraction, X-ray photoelectron spectroscopy, Raman and Fourier transform infrared spectroscopy, which established that Tiron leads to the blending of chelating and bridging bidentate geometries for F T -nano-TiO 2 , whereas chromotropic acid produces bridging bidentate as well as monodentate geometries for F C -nano-TiO 2 . The surface chemistry of the studied membranes, polysulfone (Psf): F T -nano-TiO 2 UF and Psf: F C -nano-TiO 2 UF, was profoundly influenced by the benign distributions of the nanoadditives enriched with distinctly charged sites ( − SO 3 − H + ), as evidenced by superior morphology, improved topography, enhanced surface hydrophilicity and altered electrokinetic features. The membranes exhibited enhanced solvent throughputs, viz . 3500–4000 and 3400–4300 LMD at 1 bar of transmembrane pressure, without significant compromise in their rejection attributes. The flux recovery ratios and fouling resistive behaviours of MMMs towards bovine serum albumin indicated that the nanoadditives could impart stable and appreciable antifouling activity, potentially aiding in a sustainable ultrafiltration performance.

We present the electronic transport characteristics of ternary alloy Cd(1-x)Zn(x)S nanowire networks in the dark and under white light illumination. Compared to the negligible dark current, we observed a photocurrent enhancement of up to four orders of magnitude at an intensity of 460 mW cm(-2). The time constant of the dynamic photoresponse is approximately 5 s. The current-voltage characteristics at different intensities show Ohmic behavior at low bias and space charge limited conduction (SCLC) at higher bias voltages. The SCLC behavior and slow time response indicate that the charge transport is dominated by tunneling at the percolating inter-nanowire junctions.

ZnO nanosheets, nanonails, and well-aligned nanorods were fabricated on Zn foils by a solvothermal approach using ethanol as the solvent. A lower synthesis temperature and a shorter time period favor the formation of nanosheets. By optimizing the synthesis temperature and time period, ZnO nanonails with a hexagonal cap and a long stem could be produced. A higher temperature was not favorable to produce uniform and smooth nanorods. Well-aligned ZnO nanorod arrays were produced with diameters within 100-250 nm and lengths up to approximately 6 microm when NaOH was added to the solvent. By optimizing the reaction parameters, the morphology, size, and orientation of the nanoforms could be tailored. The ZnO nanorods exhibit an excitonic strong UV emission and a defect-related broad green emission at room temperature. The defect-related green emission band decreased with the improvement of the degree of alignment of the nanorods.

Manganese-incorporated ZnS (MnxZn1-xS) nanorods were synthesized by a simple solvothermal process. Synthesized nanorods were single crystalline. Manganese incorporation in the ZnS lattice induces a phase transformation from hexagonal wurtzite to cubic zinc blende structure. The diameter of the nanorods increased with the increase of Mn concentration. Intense orange luminescence at approximately 585 nm was observed for the nanorods. Six-line hyperfine splitting was observed in the EPR spectra for lower Mn concentrations, whereas broad Lorentzian-shaped EPR spectra were obtained for higher Mn concentrations because of the Mn-Mn cluster formation at higher Mn concentrations.

Rapid synthesis of wurtzite ZnS nanowires and nanoribbons has been achieved by a simple thermal evaporation of ZnS powder onto Si substrate in the presence of Au catalyst. A vapor-liquid-solid process is proposed for the formation of the ZnS nanostructures. The flow rate of the inert carrier Ar gas along with the temperature play an important role in defining the morphology of the ZnS nanostructures. The morphological change of the ZnS nanostructures and their growth sequence were studied through scanning electron microscopy. Room-temperature photoluminescence measurements showed intense blue emission at approximately 398 nm from both the nanowires and the nanoribbons.

One-dimensional ZnO nanostructure arrays such as nanowires, nanonails, and nanotrees, have been synthesized by oxygen assisted thermal evaporation of metallic zinc on a quartz substrate over a large area. Morphological evolution of ZnO nanostructures at different time scales and different positions of the substrates have been studied by electron microscopy. A self-catalyzed vapor-liquid-solid (VLS) process is believed to be responsible for the nucleation and subsequently a vapor-solid process is operative for further longitudinal growth. The photoluminescence spectrum showed a weak UV and a broad green emission peak at 3.25 and 2.49 eV, respectively. The latter was attributed to the presence of zinc interstitial defects. Electrical resistivity as a function of temperature showed activated mechanisms to be present. The electrical response of the ZnO nanonail arrays to different gases (CO, NO 2 , and H 2 S) indicated that there could be possible application as gas sensors for this material.

Photoluminescence of large (150–200 nm) colloidal CdS nanoparticles in isopropanol was efficiently quenched by the electron donor molecule N,N-dimethylaniline (DMA). The quenching rates were found to be accelerated with improvement of the crystallinity of the CdS substrates. Electron-transfer from DMA to spherical CdS nanoclusters with 2–4 nm polycrystalline domains inside exhibited the slowest quenching rate (kq ∼ 0.65 × 1010 M−1 S−1). However the quenching rate was enhanced by ∼2 times (kq ∼ 1.2 × 1010 M−1 S−1) when crystal plane alignments were moderately improved. Further improvement of the quenching rate (kq ∼ 3.5 × 1010 M−1 S−1) was successfully achieved when the morphology of the CdS substrates was changed to nanorods. This enhancement is attributed to the single crystalline structure i.e. highly ordered crystal planes along the axis of the nanorod.

Careful optimisation of a safe and sustainable route for hydrogen production is a pressing need. Thermochemical processes employing water as raw material and nuclear/renewable energies as energy source are believed to be the best possible option in this direction, while alarming issues such as climate change and global warming are being taken into account. Amongst the well-identified cycles, the sulphur-iodine (S-I) thermochemical route assumes the highest thermal efficiency and the best one as regards its coupling to a high temperature nuclear reactor. Material development is the key issue to be addressed to realise successfully the potential of the S-I cycle. The most important area is development of gas-permeable membranes for enhancement of the equilibrium decomposition of HI, which is the most intricate step as far as the overall process efficiency is concerned. In order to overcome the low efficiency associated with the low equilibrium decomposition of HI, the authors intend to develop a hydrogen permselective membrane reactor. As a first step towards this development, a silica membrane of asymmetric nature was developed using sol-gel processing and dip coating, and characterised using scanning electron microscopy and a BET surface area analyser. A road map towards realising the successful emergence of the membrane reactor is discussed.