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The nearby ( z = 0.031 ) TeV γ -ray emitter BL Lac object Mrk 421 has been observed with the TACTIC telescope for nearly 118 hours during 01 February to 26 April, 2012 (MJD 55958–56044). Detailed analysis reveals the detection of 529 ± 76 γ -rays with 6.9 σ significance above 850 GeV energy threshold during the period of 15–26 March, 2012 (MJD 56001–56013). Nearly simultaneous multiwavelength observations of the source also indicate a comparatively higher flux state during this period (MJD 56001–56013). In this paper, we present the study of Mrk 421 during this period in very high energy (VHE) domain along with the results from high energy (HE), X-ray, optical and radio observations. We reproduce the spectral energy distribution (SED) of the source during this period using the synchrotron and synchrotron self-Compton (SSC) process. The model parameters of the emission region of the source are found to be consistent with the values reported in the literature. [ABSTRACT FROM AUTHOR]

For the present study, glass fibre reinforced polymer (GFRP) composites and GFRP composites incorporated with 0.5 wt% and 1 wt% of graphene nano-platelets (GNPs) were prepared by hand lay-up method, coupled with compression moulding. The tribological testing was conducted in dry-sliding environment with a Pin-on-disc Tribo-Tester for a running time of 10 min and under applied load of 20 N, 40 N, 60 N and 80 N. The experiment data (610 data sets) were used while applying the Artificial Neural Network (ANN) technique. The experiment results were compared with the results obtained from the ANN. It showed that the ANN predicted the output parameters with an overall percentage error of less than 5 %. ANN predicted wear for all three composite samples had the mean square error (MSE) less than 2.2005 × 10 − 2 and the coefficient of determination (R2) greater than 99 %, whereas the ANN predicted coefficient of friction for all three composite samples had the MSE less than 5.057 × 10 − 5 and R2 greater than 90 %. During the course of the present investigation, the Field-emission Scanning Electron Microscope (FESEM) and Energy-dispersive X-ray Spectroscopy (EDS) analysis were also used to examine the wear mechanism. [ABSTRACT FROM AUTHOR]

Thermal plasma pyrolysis of radioactive waste is a recommended technique to manage large volume of combustible radioactive waste comprising of rubber and plastics. A lumped parameter based numerical model, to predict the thermal behavior of a plasma pyrolysis chamber during startup, is reported in this work. The model takes into account the non-ideal flow conditions inside the plasma chamber which are specific to the geometry of the chamber. Three different non-ideal models – a Continuous Stirred Tank Reactor (CSTR) having exchange with a separate perfectly mixed CSTR like geometry, two parallel CSTRs, and two parallel CSTRs with exchange, as well as an ideal single CSTR model have been compared. The models consider heat transport from plasma chamber interior to the walls through convection as well as radiation. Resistance offered by five successive layers of insulation of different materials has been considered. The predictions from the models are compared against experimentally determined evolution of chamber temperature during startup for three different power ratings of the plasma torch. The model formulation of two parallel CSTRs with exchange (a two-parameter model) is observed to fit the experimental data the best. A detailed sensitivity analysis has been carried out and the optimum model parameters are determined. Temperature evolution of different insulation layers has also been obtained. The validated model has been used to study the temperature response of the chamber during two different types of operating transients, viz. step changes in torch power and sinusoidal variation in torch power. [ABSTRACT FROM AUTHOR]

Graphene, a single, one-atom-thick sheet of carbon atoms arranged in a honeycomb lattice and the two-dimensional building block for carbon materials, has attracted great interest for a wide range of applications. Due to its superior properties such as thermo-electric conduction, surface area and mechanical strength, graphene materials have inspired huge interest in sensing of various chemical species. In this timely review, we discuss the recent advancement in the field of graphene based gas sensors with emphasis on the use of modified graphene materials. Further, insights of theoretical and experimental aspects associated with such systems are also discussed with significance on the sensitivity and selectivity of graphene towards various gas molecules. The first section introduces graphene, its synthesis methods and its physico-chemical properties. The second part focuses on the theoretical approaches that discuss the structural improvisations of graphene for its effective use as gas sensing materials. The third section discusses the applications of pristine and modified graphene materials in gas sensing applications. Various graphene modification methods are discussed including using dopants and defects, decoration with metal/metal oxide nanoparticles, and functionalization with polymers. Finally, a discussion on the future challenges and perspectives of this enticing field of graphene sensors for gas detection is provided. [ABSTRACT FROM AUTHOR]

• Flow synthesis of ultra small Au nanoparticles (<5 nm) in PTFE microbore tube is reported. • Well dispersed, spherical Au nano particles in the size of 1.5–6.2 nm are obtained. • Effects of different operating parameters on size and polydispersity are studied. • Effect of flow segmentation using air on size of the synthesized Au nanoparticles is studied. Flow synthesis of ultrafine colloidal gold nanoparticles (AuNP) of size below 5 nm in a microreactor is reported. The gold precursor along with trisodium citrate and an additional stabilizing agent (PVP) are premixed and infused using a syringe pump into a PTFE microbore tube kept immersed inside a hot oil bath using a syringe pump. The synthesized AuNP are mostly spherical in shape. Systematic studies are conducted to investigate the effects of residence time, reaction temperature, citrate to gold ratio, presence of additional stabilizing agent and gas induced flow segmentation on the average particle size and polydispersity index. An increase in residence time is seen to reduce average particle size. Smaller sized and more monodispersed AuNP are seen to form at higher reduction temperature. An increase in citrate to gold ratio is seen to have an insignificant effect of average particle size and polydispersity index. Presence of PVP is seen to reduce average particle size and polydispersity index. Smaller and more monodispersed AuNP are seen to form when the single phase aqueous flow is segmented by gas infused through a separate syringe pump. A mechanistic picture of the synthesis process is proposed to explain the experimental trends. [Display omitted]. [ABSTRACT FROM AUTHOR]

For the present study, the tribological properties of glass-fibre reinforced epoxy (GFRE) composites and GFRE doped with 0.5 and 1 wt% of graphene nano-platelets (GNPs), were evaluated under the dry sliding condition by using pin-on-disc tribometer. Taguchi's design of experiment (DOE) was applied to find the optimal parameters for minimum specific wear rate (SWR) and coefficient of friction (COF) which occurs at load of 40 N and GNP wt% of 1. The GNP wt% was the most significant factor determined by applying analysis of variance (ANOVA). An artificial neural network (ANN) model was developed for predicting the specific wear rate and coefficient of friction with a coefficient of determination (R2) equal to 0.965 and 0.986, respectively. Surface roughness, X-ray diffraction (XRD), Field-emission scanning electron microscope (FESEM) and Electron dispersive Spectroscopy (EDS) analysis of the worn specimen were conducted to examine surface morphology and the wear behaviour. [ABSTRACT FROM AUTHOR]

An experimental study was conducted to arrest a crack in 1.0-mm-thick 6061-T6 aluminum single-edge-notch tension specimen. The specimen was repaired by symmetrical bonding of carbon fiber-reinforced polymer patches made of several plies. Although J-integral was reduced drastically, the specimen failed at one of the leading edges through separation at the interface. The separation was suppressed by tapering all the four leading edges of the patches. The specimens did not fail in the patched area when loaded up to the far field stress of 272 MPa, which was higher than the yield stress, 265 MPa of the aluminum plate. [ABSTRACT FROM PUBLISHER]

We present a long-term multi-wavelength study of the flat spectrum radio quasar 3C 279 using near simultaneous observations available from July 01, 2012 and June 31, 2018 (MJD 56109-58301). The data set includes measurements from the TACTIC , Fermi -LAT, Swift -XRT, Swift -UVOT, SMARTS, Steward-SPOL, and OVRO. The TACTIC telescope has monitored the source 3C 279 for ∼ 70 h between 2013 and 2018 in the energy range of > 0.85 TeV and yields null result. We have analysed the Fermi -LAT data to obtain the 5-day binned light curve in the energy range 0.1–300 GeV. One low and six high emission states are identified in the Fermi -LAT light curve. The high emission states are modelled with an exponential rise and decay time profile using 1-day averaged flux points and have been characterized as the asymmetric flares. The spectral analysis of near simultaneous X-ray and γ -ray data from the Swift -XRT and Fermi -LAT respectively indicates harder when brighter trend during the high activity states. The time averaged broadband spectral energy distributions corresponding to the seven states are successfully reproduced under the framework of a simple one zone leptonic emission model with IR photons originating from the dusty torus as the dominant target for the inverse Compton scattering by the relativistic electrons. Results obtained from the broadband modelling suggest that the non-thermal emission region in the jet is above the broadline region. This is also supported by the average value of seed factor estimated using the derived model parameters. A positive correlation between the bulk Lorentz factor of the emission zone and average γ -ray flux measurements for each state indicates that an increase in the bulk Lorentz factor can be the dominant cause for the observed flares from 3C 279. We also discuss the implications of the obtained model parameters in detail to understand the long-term behaviour of the source. [ABSTRACT FROM AUTHOR]

Abstract: Liquid–liquid extraction experiments have been carried out in two different types of microchannels using water (Zn) D2EHPA+dodecane system, a standard reactive extraction system recommended for evaluation of liquid–liquid extraction equipment. The microchannels used in the experiments are a t-junction serpentine microchannel and a split and recombine microchannel. Effects of O/A ratio and residence time on overall volumetric mass transfer coefficient have been studied and an attempt has been made to explain the experimental trends with the help of liquid–liquid flow patterns observed by using a high speed image acquisition system. Correlations relating overall volumetric mass transfer coefficients to O/A ratio and velocity are reported for both the microchannels. [Copyright &y& Elsevier]

Highlights: [•] NP-9 is a proven MAO-B (in vitro and in vivo)and AChE (in vitro) inhibitor. [•] It inhibited Aβ aggregation in vitro. [•] It protected memory loss induced by scopolamine and Aβ1–42 toxicity. [•] It protected neuronal loss induced by Aβ1–42 toxicity. [•] It prevented amyloid plaque deposition in Aβ1–42-induced model. [ABSTRACT FROM AUTHOR]

Radioactive scandium-46 microspheres have applications in mapping flow in a chemical reactor through a technique known as radioactive particle tracking (RPT). In the present study a novel microfluidic method has been developed for synthesis of controlled size scandium oxide microspheres. An inline/in-situ mixing of the scandium precursor and gelling agents was implemented which makes the microfluidic platform amenable for truly continuous operation. Microspheres of size varying from 937 to 666 μm were produced by varying O/A ratio from 10 to 30. Perfectly spherical and monodispersed (PDI <10 %) microspheres were obtained at O/A 15 and beyond. The morphology, elemental composition, and structure of the microspheres were analysed by SEM, EDS and XRD, respectively. Subsequently the microspheres were irradiated with thermal neutrons in a nuclear reactor to obtain radioactive Sc-46 oxide microspheres. The activity produced on each Sc-46 microspheres with different sizes was in the range 19.5–34.0 MBq. [Display omitted] • Scandium-46 oxide microspheres were synthesized through sol-gel based microfluidic method followed by neutron irradiation. • Ratio of flow rates of organic phase to aqueous phase play a vital role in controlling the size of the microspheres. • Precursor concentration optimised to obtain microspheres with appreciable mechanical property. • The scandium oxide microspheres were characterized by SEM, EDS and XRD. [ABSTRACT FROM AUTHOR]

Abstract: Flutter, a self-excited vibration resulting from the interaction between structural motion and aerodynamic force, is the major aspect in wind resistant design of cable stayed bridges. The critical speed for flutter of a deck section can be evaluated using the flutter derivatives obtained by sectional model testing of the bridge deck in a wind tunnel. Since it is very expensive, time consuming and laborious to conduct wind tunnel tests for all the practical dimensions of deck, the support vector machine (SVM) is applied for predicting the flutter derivatives for any deck size. The wind tunnel experimental data is collected from literature and SVM is trained. Thus predicted flutter derivatives are used for estimation of critical flutter velocity of cable stayed bridges. The effect of each aerodynamic derivative on flutter instability is investigated in this study. [Copyright &y& Elsevier]

Experiments are conducted to understand the effects of important geometrical and operating parameters on continuous phase axial dispersion in liquid-liquid two-phase flow in air pulsed columns having sieve plate internals and disc and doughnut shaped internals. Water is used as the continuous phase. Dodecane containing 30% (v/v) tributyl phosphate is used as the dispersed phase. Among operating parameters, superficial velocities of the dispersed phase and continuous phase are varied. Pulsing velocity also is varied. Among geometrical parameters, column diameter, disc or plate spacing are varied while conducting the experiments. Correlations for estimating continuous phase axial dispersion coefficient reported in literature are evaluated using the experimental data of this study. A previously reported correlation to estimate axial dispersion of continuous phase is found to be good for the pulsed columns having sieve plates. A new correlation is proposed for the air pulsed columns having disc and doughnut internals. [ABSTRACT FROM AUTHOR]

[Display omitted] • Development of ultrasonic sensor system to estimate ammonium nitrate concentration in thermal denitration plants. • A linear calibration is obtained for ammonium nitrate concentration (0 to 150 g/L) and temperature (34°C to 50°C) • The efficacy of the system is also shown for other nitrate bearing stream (sodium nitrate). • The system can measure fast transients (up to 40 Hz) in concentration changes. Ammonium nitrate is one of the most common wastes generated in both front and back end of nuclear fuel cycle. Accurate and online estimation of ammonium nitrate concentration assumes importance in denitration processes for treatment of this waste. An ultrasonic based concentration estimation system is developed for online estimation of ammonium nitrate concentration in process vessels. A 5 MHz ultrasonic sensor is designed for this aim. The reflected signal is acquired and processed to measure the time-of-flight (TOF) across a known distance, which, in turn, is used to estimate the speed of sound in the medium. The effect of temperature on the results is studied in detail. A linear calibration equation is generated (R2∼0.995) which can predict concentration for measured value of TOF and temperature. Range, accuracy and resolution of the system are 0−150 g/L, 1.8 g/L and 1.5 g/L respectively. Moreover, the system is able to capture rapid dynamics of concentration change, updated every 25 ms. Applicability of the system is also tested with other nitrate bearing medium (sodium nitrate streams). [ABSTRACT FROM AUTHOR]

Abstract: A356 alloy produced by means of conventional gravity die casting and rheocasting has been investigated and their microstructure, mechanical and tribological properties were compared. The microstructure of conventional cast sample is fully dendritic in contrast to spheroidal morphology in rheocast sample. The mechanical properties of the rheocast samples are considerably higher than the conventional cast samples. The volumetric wear loss and coefficient of friction in rheocast samples are always less than those in conventional cast samples at all loads. The wear occurs mainly by ploughing mechanism. [Copyright &y& Elsevier]

• A "deploy-and-forget" ultrasonic sensor system to estimate liquid-liquid interface depth. • Wavelet and match filter based ultrasound signal processing. • System works for any pair of liquids, temperature and/or liquid contamination. • System can work even for dirty interfaces (contaminated with particulates/emulsion). • Along with interface location, acoustic velocity in the liquid pair is estimated. Detection of liquid-liquid interface is critical in solvent extraction equipment/contactors typically used in petroleum and hydrometallurgical industries. An instrumentation system, comprising of a self-calibrating ultrasonic sensor and a novel signal processing algorithm is reported. It can be used to estimate location of liquid-liquid interface along with speed of sound in both the liquids without any manual/user intervention. The algorithm involves use of discrete wavelet transform and matched filter. The system has been tested at laboratory scale under wide range of industrially relevant conditions. The system works for any pair of liquid without apriori knowledge of their acoustic characteristics, is insensitive to changes in temperature and/or compositions. It also works for dirty interfaces contaminated with particulate matter or emulsion. The above mentioned features truly impart the sensor system "deploy-and-forget" capabilities. The range, accuracy and resolution of the system, with respect to interface location, are 40–200 mm, 0.45% FS (Full-scale) and less than 1 mm, respectively. [ABSTRACT FROM AUTHOR]

• Selective separation of Cu from large excess of Zn by solvent extraction in microchannel. • Stripping of Cu from loaded organic phase in microchannel. • Effects of O/A ratio and flow velocity on percentage extraction and stage efficiency. • Effects of O/A ratio and flow velocity on selectivity and overall volumetric mass transfer coefficient. A microfluidic platform, comprising a 800 μm diameter microbore tube connected to a 750 μm diameter opposed T-junction, to selectively extract copper from a large excess of zinc is reported. The effects of flow velocity (0.033 – 0.167 m/s) and ratio of the organic phase flow rate to the aqueous phase flow rate (O/A ratio, 1−2.5) on percent Cu extraction, Cu selectivity, stage efficiency, and overall volumetric mass transfer coefficient are studied. At O/A ratio of unity, maximum stage efficiency (98.90%) and maximum value of overall volumetric mass transfer (0.039 s−1) are obtained at flow velocity of 0.167 m/s. At these operating conditions, the values of % Cu extraction and Cu selectivity are 79.10% and 54.25%, respectively. Back extraction/stripping studies are also carried out to recover Cu in pure form in the strippant phase. Cu purity as high as 99% is obtained for O/A ratio of 1 and flow velocity of 0.167 m/s. High speed imaging studies are carried out to investigate the liquid-liquid two-phase flow pattern in the microchannels both during extraction as well as stripping. [ABSTRACT FROM AUTHOR]

• Synthesis of uniform spherical polyacrylamide (PAM) hydrogel beads in microreactors by using inverse suspension polymerization. • Segmentation of aqueous reaction phase by using an organic carrier phase. • Effect of ratio of the volumetric flow rates of the organic carrier phase and the aqueous phase. • Effect of tube diameter, design of the microfluidic junction and monomer concentration on quality of beads. • Comparison of in-situ mixing and ex-situ mixing methods. A microreactor based continuous inverse suspension polymerization method for synthesis of uniform spherical polyacrylamide (PAM) hydrogel beads is reported. Aqueous phase containing monomer, cross-linker and initiator was dispersed in the form of droplets into a carrier phase (dodecane) by using a microfluidic T-junction. The residence time for the reaction was provided by a microbore tube connected to the T-junction. The effects of factors such as O/A ratio (ratio of the volumetric flow rates of the organic carrier phase and the aqueous phase), microbore tube diameter, design of the microfluidic junction and monomer concentration on the shape, size and uniformity of the beads formed were studied in detail. Two different mixing approaches – in-situ mixing and ex-situ mixing – were also compared. The size of the beads could be varied by changing the O/A ratio. The design of the microfluidic junction and the diameter of the residence time element were found to have significant effect on the size and shape of the beads. Spherical and monodispersed (polydispersity index < 10 %) PAM hydrogel beads could be synthesized by using the microreactor comprising 800 μm diameter microfluidic T-junction as the dispersing device followed by a microbore tube serving as the residence time element. [ABSTRACT FROM AUTHOR]

• Observation with TACTIC telescope in search for TeV gamma-rays above 0.85 TeV energy from NGC 1275. • Nearly simultaneous observation with Fermi-LAT, Swift-XRT, Swift-UVOT and OVRO to understand the broad-band emission. • Variability study in different energy band. • Comparing the broad-band spectral energy distributions in different emission states. Located in the Perseus galaxy cluster, NGC 1275 (z = 0.0179), is the brightest radio galaxy detected in both high energy (HE ; E > 100 MeV) and very high energy (VHE ; E > 100 GeV) regimes. Here we present the results from the observations of NGC 1275 with TACTIC for 37.1 h between December, 2016 and February, 2017. In the absence of a statistically significant VHE γ -ray detection from the TACTIC observations, we estimate the 3 σ upper limit on the integral flux above 0.85 TeV to be ∼ 2.85 × 10 − 11 erg cm − 2 s − 1 . We also report the results of near simultaneous multiwavelength observations of the source from the Fermi -LAT, Swift -XRT/UVOT and OVRO. We find the source to be in flaring state on the night of 31 December, 2016 – 1 January, 2017 when the HE γ -ray flux above 0.1 GeV went up to ∼ 2.0 × 10 − 6 ph cm − 2 s − 1 which is approximately 4 times the flux level during its low state. We present the broad-band spectral energy distributions (SED) of the source during its flaring and low states. It is evident from the SED that the VHE upper limit obtained from the TACTIC observations is consistent with the low emission state of the source. [ABSTRACT FROM AUTHOR]

A continuous process to obtain ammonium diurate directly from uranium-loaded organic phase in a microbore tube is presented. The proposed process combines two different steps: multistage stripping and precipitation in a microbore tube. The effects of different operating conditions (residence time, O/A ratio, and flow velocity) on percent uranium removal, production rate, and space–time–yield (STY) have been studied. Percent uranium removal as high as 99.5% is attained within a residence time of 3 min for O/A ratio of 4. Corresponding value of STY is 3000 kg/day-m3 while ensuring a uranium concentration below 50 ppm in lean organic phase. Numerical simulations are carried out to understand the two-phase flow pattern inside the microbore tube. The results of the simulations are used to substantiate and explain the observed experimental trends. [ABSTRACT FROM AUTHOR]

Since 2002, Gravity Recovery and Climate Experiment (GRACE) satellite has provided monthly estimates of land water storage variations by monitoring time-variable components of earth's gravity field. We present GRACE satellite RL05 gravity data at 1° × 1° resolution to estimate terrestrial water storage change (surface water + groundwater) over India during Indian Summer Monsoon (ISM) and Northeast (NE) monsoon periods for the year 2015. As the NE monsoon was above normal in 2015, groundwater storage has increased significantly. By using GLDAS2.1 (1° × 1° resolution data) land surface state variables, we deduced as to how Terrestrial Water Storage (TWS) is partitioned into canopy water and soil moisture components. By computing storage changes in GRACE TWS, Global Land Data Assimilation System (GLDAS) land surface state variables and by using a terrestrial-based water balance approach, we calculated changes in the groundwater storage. The GRACE data indicate the variation of 15 cm in the TWS during the ISM period over India and a gain of 2.35 cm NE season over Peninsular India. After the ISM season, the groundwater storage was increased by 13 cm over India and 6.45 cm during the NE monsoon over Peninsular India. We also observed a high run-off (sub-surface + surface) rate in both the monsoon periods. The accumulated rainfall over India was estimated as 76.58 cm out of which 33.8 cm was computed as run-off (ISM season). Similarly, the mean rainfall in Peninsu lar India was calculated as 8 cm out of which 3.86 cm was approximated as run-off (NE monsoon season). [ABSTRACT FROM AUTHOR]

Abstract: In the treatment of mild to medium severe atopic dermatitis a new formulation proved to be highly efficient. The formulation is based on a combination of microsilver and nanolipid carriers (NLC) incorporated into an o/w cream and a lotion. A theory of action was proposed, the formation of silver–NLC complex (sNLC). In this study this theory was proven, and based on this new mechanism two new approaches for dealing with AD are suggested to distinctly improve AD treatment, i.e. increasing efficiency, reducing drug exposure and reducing side effects. The antimicrobial silver ions adsorb onto the surface of the negatively charged NLC (=sNLC complex). The sNLC as nanoparticles are highly adhesive to skin and bacterial surfaces, leading to a locally high concentration of silver ions killing the bacteria, much more effective than silver alone. The NLC restore the distorted skin barrier. Based on this a new two-step approach is suggested: (1) “treatment-supportive consumer care” by restoring the normal skin condition (NLC for barrier restoration plus synergistic antibacterial silver–NLC complex) and (2) “drug-loaded consumer care AD formulations”. i.e. incorporating drugs into the NLC of this consumer care formulation. NLC incorporation makes the drugs more effective (penetration enhancement) and simultaneously exploits the skin normalization ability of the skin care sNLC formulation, future drug candidates being prednicarbate and tacrolimus. [Copyright &y& Elsevier]

Abstract: Composite membranes with mordenite (MOR) incorporated in poly vinyl alcohol (PVA)–polystyrene sulfonic acid (PSSA) blend tailored with varying degree of sulfonation are reported. Such a membrane comprises a dispersed phase of mordenite and a continuous phase of the polymer that help tuning the flow of methanol and water across it. The membranes on prolonged testing in a direct methanol fuel cell (DMFC) exhibit mitigated methanol cross-over from anode to the cathode. The membranes have been tested for their sorption behaviour, ion-exchange capacity, electrochemical selectivity and mechanical strength as also characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis. Water release kinetics has been measured by magnetic resonance imaging (NMR imaging) and is found to be in agreement with the sorption data. Similarly, methanol release kinetics studied by volume-localized NMR spectroscopy (point resolved spectroscopy, PRESS) clearly demonstrates that the dispersion of mordenite in PVA–PSSA retards the methanol release kinetics considerably. A peak power-density of 74mW/cm2 is achieved for the DMFC using a PVA–PSSA membrane electrolyte with 50% degree of sulfonation and 10wt.% dispersed mordenite phase. A methanol cross-over current as low as 7.5mA/cm2 with 2M methanol feed at the DMFC anode is observed while using the optimized composite membrane as electrolyte in the DMFC, which is about 60% and 46% lower than Nafion-117 and PVA–PSSA membranes, respectively, when tested under identical conditions. [Copyright &y& Elsevier]

Abstract: With the fast depletion of petroleum reserves, renewable resources like biomass are acquiring great significance. Calotropis procera, a laticiferous arid plant is identified as a potential petrocrop. The dried biomass of C. procera was subjected to non-polar (n-heptane) solvent extraction. Biocrude so obtained is a rich source of tri terpenoid type of hydrocarbons. The biocrude was upgraded to useful liquid fuels using different conversion processes such as thermal and catalytic cracking (fluid catalytic cracking, FCC). The temperature, pressure and reaction time maintained during thermal conversions were 430 and 460°C; 1.2 and 0.2MPa; and 15 and 30min, respectively. Catalytic cracking was carried out in continuous mode micro reactor varying the catalyst to feed ratio (3–7.03) and temperature (460–520°C) aiming at maximization of lighter fractions (up to diesel range). High conversions (up to 92%) were obtained using FCC as compared to thermal process (57.7%). The HPLC analysis of the liquid fuels indicated that thermal cracking yielded a better quality fuel compared to FCC. The fuel obtained by FCC was found to contain large proportions of aromatics and poly-aromatic hydrocarbons (PAH). [Copyright &y& Elsevier]

Abstract: Chemical warfare agents (CWA''s) are defined as any chemical substance whose toxic properties are utilised to kill, injure or incapacitate an enemy in warfare and associated military operations. Chemical agents have been used in war since times immemorial, but their use reached a peak during World War I. During World War II only the Germans used them in the infamous gas chambers. Since then these have been intermittently used both in war and acts of terrorisms. Many countries have stockpiles of these agents. There has been a legislative effort worldwide to ban the use of CWA''s under the chemical weapons convention which came into force in 1997. However the manufacture of these agents cannot be completely prohibited as some of them have potential industrial uses. Moreover despite the remedial measures taken so far and worldwide condemnation, the ease of manufacturing these agents and effectiveness during combat or small scale terrorist operations still make them a powerful weapon to reckon with. These agents are classified according to mechanism of toxicity in humans into blister agents, nerve agents, asphyxiants, choking agents and incapacitating/behavior altering agents. Some of these agents can be as devastating as a nuclear bomb. In addition to immediate injuries caused by chemical agents, some of them are associated with long term morbidities and psychological problems. In this review we will discuss briefly about the historical background, properties, manufacture techniques and industrial uses, mechanism of toxicity, clinical features of exposure and pharmacological management of casualties caused by chemical agents. [Copyright &y& Elsevier]

Dissolution of carbon in liquid iron melt is one of the very important reactions in chemical and metal processing industries, as it decides, in many cases, the productivity of a process or quality of the product. As a result, the current investigation was undertaken to study the effect of different physical and chemical characteristics of five types of carbon sources on dissolution kinetics. Bath chemistry being a very important factor in determining the process, two types of iron bearing materials, namely, electrolytic iron and sponge iron were employed for the study. It has been found that though the ash in carbon exhibits significant effect on carbon dissolution, the influence of the volatile matter was not found to be noteworthy. It has also been observed that petroleum coke undergoes maximum dissolution possibly due to its porous structure as well as less amount of inherent impurity. Silicon is found to be a strong promoter of the kinetics whereas the depressing effect of sulphur is not found to be that pronounced. Preliminary results of a mathematical model shows that the dissolution in Tamman furnace takes place under constant heat flux condition. [Copyright &y& Elsevier]

Magneto-resistance studies in a high-Tc granular superconductor Bi1.7Pb0.3Sr2Ca2Cu3Ox in an applied magnetic field ranging from 0 to 0.6 T in the low current limits (1 mA) have been carried out to understand the dissipation mechanism in high-Tc superconducting materials. The Kosterlitz–Thouless (KT) as well as the Ambegaoker–Halperin (AH) widely employed models are invoked to interpret the results. The KT theory is found to account for dissipation in the temperature range TKT, i.e. between the Kosterlitz–Thouless temperature and the Ginzberg–Landau transition temperature. The dissipation around Tc cannot be explained adequately. It is suggested that dissipation in the entire range of temperature can be accounted for on the basis of a modified Ambegaokar–Halperin theory incorporating two mechanisms, viz. vortex-dynamics and the fluctuations of the order parameter and the two mechanisms crossover at a transition temperature (TBP). [Copyright &y& Elsevier]

• Vacuum compression moulded Basalt-Polyeteherimide (PEI) composites manufacturing. • Optimization of Basalt-PEI composite manufacturing moulding parameters. • Basalt-PEI composite under quasi-static and dynamic high strain rate loading. • Elastic recovery of Basalt-PEI composite can help in reflecting the blast wave. High temperature blast and ballistic resistant light weight fibre reinforced plastic composites are very much in demand. Accordingly, the present investigation is focused on the quasi-static and high strain rate behaviour of Basalt/Polyetherimide (PEI) composite. Nine different types of composite samples were fabricated by compression moulding. The moulding pressures and temperatures were varied in the range of 15–25 bars and 325 °C−375 °C, respectively. Quasi-static testing was done at the rate of 3 mm/min to establish the optimum moulding parameters. High strain rate compression tests in the strain rate range of 900/s−3200/s were performed on the optimum moulded composite specimens. High strain rate testing revealed that 40 layered Basalt/PEI composite moulded at 25 bar pressure and 350 °C attained highest stress of 932 MPa whereas, the same was found to attain 446 MPa under quasi-static loading conditons. Thus, establishing the rate depedency of Basalt/PEI composite. Damage studies revealed that Basalt/PEI undergoes brittle damage, typically resulting in shear plane angle of 42°−45°. SEM micrographs revealed brittle fibre failure and matrix free fibre bundles, indicating the importance of process parameter optimiation. [ABSTRACT FROM AUTHOR]

This study aims to assess the glaciers change status in Shyok basin, East Karakoram in terms of area and mass balance, and to ascertain if glaciers in this part of Karakoram also display similar anomaly like central or western counterparts. The spatio-temporal monitoring of glaciers during the time frame of 24 years (1990/2000/2014) suggests major percentage of stable glaciers and insignificant retreat in the total glaciated area. The percentage of retreating glaciers has increased after year 2000. Area change analysis of glaciers having size >1 km2 (569 glaciers) suggests the number of fluctuated glaciers have substantially increased i.e. overall 56% glaciers remained stable, 35% retreated and 9% advanced during 1990–2014. The geodetic based findings using SRTM-C (2000) and Cartosat-1 (2010/2011/2014) stereo-imageries for 201 glaciers suggest the mass loss at the rate of −0.10 ± 0.07 m w.e. a−1. To better apprehend the status of glaciers changes in the region, climatic studies using in-situ observations as well as reanalysis dataset (ERA-I) were also undertaken of past 30 years. Therefore, this study is also a maiden attempt to ascertain if along with Karakoram anomaly, a climatic anomaly exists in the Eastern parts of Karakoram or not. A long term field collected snow-meteorological data of East Karakoram region suggests overall warming trend in annual temperature and no trend for snowfall during 1985–2015. The statistically significant increased rates of warming and decreased snowfall after year 2000 support the spatial variations in glaciers of East Karakoram and marginal mass loss. The observations of the marginal mass loss along with warming temperatures indicate that no Karakoram or climatic anomaly is existent over the East Karakoram region. Our study further refutes the prevalence of the elevation-dependent warming (EDW) over East Karakoram region vis-à-vis North-West Himalayan ranges. The impact of hiatus in global warming was also not observed over studied region. Unlabelled Image • Glaciers of East Karakoram depicted overall negative mass balance rate with marginal mass loss in early 21st century. • Spatio-temporal analysis of glaciers depicted negative area change rate with majority of the glacier in stable state. • Climate of East Karakoram revealed increased rates of warming and decreased snowfall after year 2000. • No Karakoram Anomaly observed over East Karakoram region like central or western counterparts in early 21st century. [ABSTRACT FROM AUTHOR]

• Elevation of CO 2 (eC) and both CO 2 and temperature (eCeT) showed 32–47% yield advantage. • Stomatal conductance reduced by18-42% under eC and eCeT. • Significantly higher profile moisture storage and lower crop ET under eC and eCeT. • Water use efficiency increased by 37–50% under eC and eCeT treatments. • Reduction in soil evaporation due to higher leaf coverage explains lower water use. Rising concentration of atmospheric carbon dioxide (CO 2) is reported to cause fertilization effect resulting in enhanced crop biomass and yields and may alter the water use of plants. However, factors like air temperature and nitrogen (N) management could modify the feedbacks of CO 2 on crop water use. Hence, this field study was carried out in open top field chambers (OTC) for two crop seasons to investigate the interactive effects of climate and N on evapotranspiration, yield and water use efficiency in soybean (Glycine max L.). Soybean crop was grown under three climate conditions (ambient : AC, elevated CO 2 : eC, and co-elevation of both CO 2 and temperature : eCeT) and four N treatments during July to October 2016 and 2018. Elevation of CO 2 was done to the level of 535–540 μmol mol−1, and temperature was elevated by about 2 °C above ambient. The four N levels were N 0 , N 50 , N 100 and N 150 referring to 0, 50, 100 and 150% of recommended N dose (30 kg N ha−1). Crop evapotranspiration (ET) was computed by soil water balance method. The two years' field study indicated eC and eCeT showed significant yield advantage to the extent of 32-47% over ambient. Significant effect (P < 0.05) of climate was observed on crop ET, profile water storage and water use efficiency (WUE) during both the study years. The effect of N application on these three parameters was significant only in 2016 crop year. Averaged across N treatments, profile soil water storage at harvest was higher by about 5% in 2016 and by 9% in 2018 crop season under eC and eCeT treatments as compared to AC. The crop ET was significantly lower under eC and eCeT in both the years, with significantly higher WUE. The WUE varied from 2.99 to 4.48 kg ha−1 mm−1 in 2016 and from 4.62 to 6.42 kg ha−1 mm−1 in 2018 crop year. Stomatal conductance during major growth period reduced by 21–42% under eC and by 19–31% under eCeT, though it did not reflect in reduced transpiration. The study indicated significantly higher leaf area contributing to reduced soil water evaporation is the major mechanism explaining higher soil water profile under eC and eCeT. Over ambient, the WUE was higher by 48-50% in 2016 and by 37-39% in 2018 under eC and eCeT treatments, which was mostly attributed to higher grain yield. [ABSTRACT FROM AUTHOR]

• Intensification of process of recovery of uranium from lean aqueous streams. • Microfluidic extraction of uranium from aqueous phase by using 30%TBP-dodecane. • Microfluidic direct precipitation of uranium from loaded organic by using NH 4 (OH). • Effects of residence time, O/A ratio and velocity on direct precipitation step. • Confirmation of reusability of organic phase. A continuous, compact process based on microfluidic extraction and microfluidic direct precipitation is presented for recovery of uranium from lean streams. The process involves extraction of uranium from an aqueous phase by using 30% (v/v) tributylphosphate (TBP) in dodecane as solvent followed by precipitation of uranium from loaded solvent using ammonium hydroxide. The effect of the ratio of volumetric flow rates of the organic phase and aqueous phase (O/A ratio) on the extraction step and the effects of O/A ratio, flow velocity and concentration of ammonium hydroxide on the direct precipitation step are studied. At optimum conditions, lean aqueous stream is contacted with the organic phase in a microchannel at a total throughput of 10 mL/min (O/A = 2) to extract 90% of uranium present in the aqueous phase. Loaded organic phase is subsequently contacted with ammonium hydroxide in a microchannel (O/A = 6) for about 92% recovery of extracted uranium in the form of ammonium diuranate (ADU). Space-time-recovery attained in the extraction and precipitation steps are 1,141,373 and 1,047,163 gm U/day/m3, respectively. Continuous operation without chocking despite solid precipitation and reusability of the organic phase are demonstrated. [ABSTRACT FROM AUTHOR]