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Bent Core Mesogens are remarkably interesting achiral Liquid Crystals. These grab attention for their utility. The compound, taken for investigation, is a Schiff base addition product, composed of 2-(4?-aminophenyl)-5-(4??-butyloxyphenyl)-1,3,4- thiadiazole and 4-n-hexadecyloxy salicylaldehyde. The property of this imine derivative is in accordance with liquid crystal and is a Bent Core Mesogen (BCM). The thin layers were prepared with the help of Langmuir-Blodgett apparatus. The morphology and photo-physical characteristics of thin films were examined in comparison to similar BCM derivative of 1,3,4-Oxadiazole. The expectation was the formation of monolayer of molecules on the substrate. Practically there were layer of clusters on the substrate. Both molecules form nano clusters. The typically different aggregates by the thiadiazole moiety in comparison to oxadiazole moiety are revealed. Cluster formation is also supported by the Atomic Force Microscopic (AFM) images.

Bent Core Mesogens are remarkably interesting achiral Liquid Crystals. These grab attention for their utility. The compound, taken for investigation, is a Schiff base addition product, composed of 2-(4?-aminophenyl)-5-(4??-butyloxyphenyl)-1,3,4- thiadiazole and 4-n-hexadecyloxy salicylaldehyde. The property of this imine derivative is in accordance with liquid crystal and is a Bent Core Mesogen (BCM). The thin layers were prepared with the help of Langmuir-Blodgett apparatus. The morphology and photo-physical characteristics of thin films were examined in comparison to similar BCM derivative of 1,3,4-Oxadiazole. The expectation was the formation of monolayer of molecules on the substrate. Practically there were layer of clusters on the substrate. Both molecules form nano clusters. The typically different aggregates by the thiadiazole moiety in comparison to oxadiazole moiety are revealed. Cluster formation is also supported by the Atomic Force Microscopic (AFM) images.

An efficient and generalized method of end-game algorithm has been proposed to engage air-borne evaders, including high-speed, highly maneuvering, and small evaders, such as unmanned aerial vehicles (UAVs). Performance of interceptors using time delay estimation and guidance integrated real-time prediction algorithm has been simulated to estimate the errors in engaging maneuvering evader targets. After extensive modeling of engagement geometry and simulation studies of the proposed algorithm, it is concluded that the algorithm can be used for defeating ballistic as well as maneuvering targets with higher accuracy compared to other methods that are reported in the literature. The accuracy of estimation is found to improve by 12% over the reported methods used for engaging maneuvering evaders. The algorithm is implemented in hardware and results are presented for a typical case of engagement geometry against a small maneuvering target, which ensured maximum damage to the target. © 1965-2011 IEEE.

An efficient and generalized method of end-game algorithm has been proposed to engage air-borne evaders, including high-speed, highly maneuvering, and small evaders, such as unmanned aerial vehicles (UAVs). Performance of interceptors using time delay estimation and guidance integrated real-time prediction algorithm has been simulated to estimate the errors in engaging maneuvering evader targets. After extensive modeling of engagement geometry and simulation studies of the proposed algorithm, it is concluded that the algorithm can be used for defeating ballistic as well as maneuvering targets with higher accuracy compared to other methods that are reported in the literature. The accuracy of estimation is found to improve by 12% over the reported methods used for engaging maneuvering evaders. The algorithm is implemented in hardware and results are presented for a typical case of engagement geometry against a small maneuvering target, which ensured maximum damage to the target. © 1965-2011 IEEE.

An efficient and generalized method of end-game algorithm has been proposed to engage air-borne evaders, including high-speed, highly maneuvering, and small evaders, such as unmanned aerial vehicles (UAVs). Performance of interceptors using time delay estimation and guidance integrated real-time prediction algorithm has been simulated to estimate the errors in engaging maneuvering evader targets. After extensive modeling of engagement geometry and simulation studies of the proposed algorithm, it is concluded that the algorithm can be used for defeating ballistic as well as maneuvering targets with higher accuracy compared to other methods that are reported in the literature. The accuracy of estimation is found to improve by 12% over the reported methods used for engaging maneuvering evaders. The algorithm is implemented in hardware and results are presented for a typical case of engagement geometry against a small maneuvering target, which ensured maximum damage to the target. © 1965-2011 IEEE.

An efficient and generalized method of end-game algorithm has been proposed to engage air-borne evaders, including high-speed, highly maneuvering, and small evaders, such as unmanned aerial vehicles (UAVs). Performance of interceptors using time delay estimation and guidance integrated real-time prediction algorithm has been simulated to estimate the errors in engaging maneuvering evader targets. After extensive modeling of engagement geometry and simulation studies of the proposed algorithm, it is concluded that the algorithm can be used for defeating ballistic as well as maneuvering targets with higher accuracy compared to other methods that are reported in the literature. The accuracy of estimation is found to improve by 12% over the reported methods used for engaging maneuvering evaders. The algorithm is implemented in hardware and results are presented for a typical case of engagement geometry against a small maneuvering target, which ensured maximum damage to the target. © 1965-2011 IEEE.

Patchy occurrences of elevated As are often encountered in groundwater from the shallow aquifers (<50 m) of the Bengal Delta Plain (BDP). A clear understanding of various biogeochemical processes, responsible for As mobilization, is very important to explain this patchy occurrence and thus to mitigate the problem. The present study deals with the periodical monitoring of groundwater quality of five nested piezometeric wells between December 2008 and July 2009 to investigate the temporal changes in groundwater chemistry vis-a-vis the prevalent redox processes in the aquifer. Geochemical modeling has been carried out to identify key phases present in groundwater. A correlation study among different aqueous redox parameters has also been performed to evaluate prevailing redox processes in the aquifer. The long term monitoring of hydrochemical parameters in the multilevel wells together with hydrogeochemical equilibrium modeling has shown more subtle differences in the geochemical environment of the aquifer, which control the occurrence of high dissolved As in BDP groundwater. The groundwater is generally of Ca-HCO3 type. The dissolved As concentration in groundwater exceeded both WHO and National drinking water standard (Bureau of Indian Standards; BIS, 10 mu g L-1) throughout the sampling period. The speciation of As and Fe indicate persistent reducing conditions within the aquifer [As(III): 87-97% of As-T and Fe(II): 76-96% of Fe-T]. The concentration of major aqueous solutes is relatively high in the shallow aquifer (wells A and B) and gradually decreases with increasing depth in most cases. The calculation of SI indicates that groundwater in the shallow aquifer is also relatively more saturated with carbonate minerals. This suggests that carbonate mineral dissolution is possibly influencing the groundwater chemistry and thereby controlling the mobilization of As in the monitored shallow aquifer. Hydrogeochemical investigation further suggests that Fe and/or Mn o, QC 20110504

Arsenic (As) induced identifiable health outcomes are now spreading across Indian subcontinent with continuous discovery of high As concentrations in groundwater. This study deals with groundwater hydrochemistry vis-a-vis As exposure assessment among rural population in Chakdaha block, West Bengal, India. The water quality survey reveals that 96% of the tubewells exceed WHO guideline value (10 mu g/L of As). The groundwaters are generally anoxic (-283 to -22 mV) with circum-neutral pH (6.3 to 7.8). The hydrochemistry is dominated by HCO3- (208 to 440 mg/L), Ca2+ (79 to 178 mg/L) and Mg2+ (17 to 45 mg/L) ions along with high concentrations of As-T (As total, below detection limit to 0.29 mg/L), Fe-T (Fe total, 1.2 to 16 mg/L), and Fe(II) (0.74 to 16 mg/L). The result demonstrates that Fe(II)-Fe(III) cycling is the dominant process for the release of As from aquifer sediments to groundwater (and vice versa), which is mainly controlled by the local biogeochemical conditions. The exposure scenario reveals that the consumption of groundwater and rice are the major pathways of As accumulation in human body, which is explained by the dietary habit of the surveyed population. Finally, regular awareness campaign is essential as part of the management and prevention of health outcomes. (c) 2010 Elsevier Ltd. All rights reserved., QC 20110207

Bengal Delta region is currently confronted with largest groundwater arsenic calamity in history of human kind (BGS-DPHE, 2001; Mukherjee and Bhattacharya, 2001; Bhattacharya et al., 2002a; McArthur et al., 2001; Smedley and Kinniburgh, 2002; Mukherjee et al., 2006; Nath et al., 2005, 2007, 2008). Concentrations of arsenic in drinking water wells in the region often exceed the WHO drinking water guideline value (10 μg L-1) and the national safe limit of both India and Bangladesh for arsenic in drinking water (Smedley and Kinniburgh, 2002; RGNDWM, 2002; CGWB, 1999; Bhattacharya et al., 2002a). About one third (35 million) population inhabiting in this region (West Bengal and Bangladesh), currently at risk of long-term arsenic exposure (Bhattacharya et al., 2001; RGNDWM, 2002; Chakraborti et al., 2004; Kapaj et al., 2006), are being diagnosed with a wide spectrum of adverse health impacts including skin disorders such as hyper/hypo-pigmentation, keratosis and melanosis and are also in hot-spot areas of BDP which is reflected in a rise in the number of cancer cases (Guha Mazumdar et al., 1988). The distribution pattern of arsenic occurrence in BDP is patchy and there are numerous hotspots of arsenic contamination in the semi-confined shallow Holocene aquifer (Bhattacharya et al., 1997; Smedley and Kinniburgh, 2002). The scale of the problem is serious both in terms of hotspots and geographic area coverage (173 × 10 3 km2, eastern part of Hoogly-Bhagirathi/Western part of Ganga-Padma-lower Meghna flood plains)., QC 20120217, Swedish Research Council (VR)-Swedish International Development Cooperation Agency (Sida), MISTRA, Rajiv Gandhi national Drinking Water Mission, India

Opioid use, particularly morphine, is linked to CNS-related disorders, comorbidities, and premature death. Morphine, a widely abused opioid, poses a significant global health threat and serves as a key metabolite in various opioids. Here, we present a turn-off fluorescent sensor capable of detecting morphine with exceptional sensitivity and speed in various samples. The fluorescent sensor was developed through the dimerization process of 7-methoxy-1-tetralone and subsequent demethylation to produce the final product. Despite morphine possessing inherent fluorophoric properties and emitting light in an approximately similar wavelength as the sensor’s fluorescent blue light, the introduction of the target molecule (morphine) in the presence of the sensor caused a reduction in the sensor’s fluorescence intensity, which is attributable to the formation of the sensor–morphine complex. By utilizing this fluorescence quenching sensor, the chemo-selective detection of morphine becomes highly feasible, encompassing a linear range from 0.008 to 40 ppm with an impressive limit of detection of 8 ppb. Consequently, this molecular probe demonstrates a successful application in determining trace amounts of morphine within urine, yielding satisfactory analytical results. The study also explores the effect of several variables on the sensor’s response and optimizes the detection of morphine in urine using a response surface methodology with a central composite design.

This study identifies causes of rising arsenic (As) concentrations over 17 years in an inter-montane aquifer system located just north of the Trans-Mexican-Volcanic-Belt in the Mesa central physiographic region that is extensively developed by long-screened production wells. Arsenic concentrations increased by more than 10 µg/L in 14% (3/22) of re-sampled wells. Similarly, in a larger scale analysis wherein As concentrations measured in 137 wells in 2016 were compared to interpolated, baseline concentrations from 246 wells in 1999, As concentrations rose more than 10 µg/L in 30% of wells. Between 1999 and 2016, the percentage of all wells sampled in each basin-wide sampling campaign exceeding the World Health Organization's 10 µg/L drinking water limit increased from 38 to 64%. Principal Components Analysis (PCA), step-wise multiple regression, and Random Forest modeling (RF) revealed that high As concentrations are closely associated with high pH and temperature, and high concentrations of fluoride (F), molybdenum (Mo), lithium (Li), sodium (Na) and silica (Si), but low calcium (Ca) and nitrate (NO3) concentrations. Pumping-induced mixing with hot, geothermally impacted groundwater generates alkaline water through hydrolysis of silicate minerals. The rising pH converts oxyanion sorption sites from positive to negative releasing As (and Mo) to pore waters. The negative correlation between nitrate and As concentrations can be explained by conservative mixing of shallow, young groundwater with geothermally influenced groundwater. Therefore water carrying an anthropogenic contaminant dilutes water carrying geogenic contaminants. This process is enabled by long well screens. Over-exploitation of aquifers in geothermal regions for agriculture can drive As concentrations in water from production wells to toxic levels even as the total dissolved solids remain low.