Water is of fundamental importance for life on earth. The synthesis and structure of cell constituents and transport of nutrients into the cells as well as body metabolism depend on water. The ...contaminations present in water disturb the spontaneity of the mechanism and result in long/short-term diseases. The probable contaminations and their possible routes are discussed in the present review. Continued research efforts result in some processes/technologies to remove the contaminations from water. The review includes concepts and potentialities of the technologies in a comprehensible form. It also includes some meaningful hybrid technologies and promising awaited technologies in coming years.
The removal of Cr(VI) from aqueous solution by batch adsorption technique using different low-cost adsorbents was investigated. Adsorbents such as clarified sludge—a steel industry waste material, ...rice husk ash, activated alumina, fuller's earth, fly ash, saw dust and neem bark were used to determine the adsorption efficiency. The influence of pH, adsorbent type and concentration, initial Cr(VI) concentration and contact time on the selectivity and sensitivity of the removal process were investigated. Adsorption process was found to be highly pH dependent. The optimum pH range for adsorption of Cr(VI) was found to be between 2 and 3. Kinetics studies were performed to understand the mechanistic steps of the adsorption process and the rate kinetics for the adsorption of Cr(VI) was best fitted with the pseudo-2nd-order kinetic model. Langmuir and Freundlich adsorption isotherms were applicable to the adsorption process and their constants were evaluated. The thermodynamic equilibrium constant and the Gibbs free energy were determined for each system. The adsorption capacity (
q
max) calculated from Langmuir isotherm and the Gibbs free energy (Δ
G
o) value obtained for the different adsorbents showed that clarified sludge was the most effective among the selected adsorbents for the removal of Cr(VI) from aqueous solution. The adsorption efficiencies of rice husk ash and activated alumina were also equally comparable with that of clarified sludge.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Using first-principles density functional calculations, we show that a transition-metal (TM)-doped defected graphene sheet with periodic repetition of a C atom vacancy (Vc) can be used as a promising ...system for hydrogen storage. The TM atoms adsorbed above and below the defected site are found to have a strong bonding to the graphene sheet, thereby circumventing the problem of TM clustering, which is the main impediment for efficient hydrogen storage in nanostructure systems. The results reveal that, when the vacancy-modulated graphene sheet is decorated on both sides by a combination of less than half-filled (TM1) and more than half-filled (TM2) elements, it results in the adsorption of molecular hydrogen with a binding energy lying in the desirable energy window. Among all the different TM1−TM2 combinations at a C vacancy site, Fe−Ti turns out to be the best choice where five H2 molecules get attached on each pair. To underscore the stability of these hydrogenated systems, we have performed an ab initio molecular dynamics simulation for a fully decorated defected graphene structure. The results show that, at room temperature, the system is stable with a gravimetric efficiency of 5.1 wt % of hydrogen, whereas desorption starts only at ∼400 K.
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IJS, KILJ, NUK, PNG, UL, UM
The generation of electrical voltage through the flow of an electrolyte over a charged surface may be used for energy transduction. Here, we show that enhanced electrical potential differences (i.e., ...streaming potential) may be obtained through the flow of salt water on liquid-filled surfaces that are infiltrated with a lower dielectric constant liquid, such as oil, to harness electrolyte slip and associated surface charge. A record-high figure of merit, in terms of the voltage generated per unit applied pressure, of 0.043 mV Pa
is obtained through the use of the liquid-filled surfaces. In comparison with air-filled surfaces, the figure of merit associated with the liquid-filled surface increases by a factor of 1.4. These results lay the basis for innovative surface charge engineering methodology for the study of electrokinetic phenomena at the microscale, with possible application in new electrical power sources.
We focus on sparse modelling of high-dimensional covariance matrices using Bayesian latent factor models. We propose a multiplicative gamma process shrinkage prior on the factor loadings which allows ...introduction of infinitely many factors, with the loadings increasingly shrunk towards zero as the column index increases. We use our prior on a parameter-expanded loading matrix to avoid the order dependence typical in factor analysis models and develop an efficient Gibbs sampler that scales well as data dimensionality increases. The gain in efficiency is achieved by the joint conjugacy property of the proposed prior, which allows block updating of the loadings matrix. We propose an adaptive Gibbs sampler for automatically truncating the infinite loading matrix through selection of the number of important factors. Theoretical results are provided on the support of the prior and truncation approximation bounds. A fast algorithm is proposed to produce approximate Bayes estimates. Latent factor regression methods are developed for prediction and variable selection in applications with high-dimensional correlated predictors. Operating characteristics are assessed through simulation studies, and the approach is applied to predict survival times from gene expression data.
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BFBNIB, INZLJ, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK, ZRSKP
Water pollution due to fluoride (F
−
) is a significant threat worldwide. Fluoride contamination affects many life forms (both plants and humans) when they enter the food chain. ...Poly(piperazine-amide) membranes have a promising role in nanofiltration activities. However, piperazine, as a cyclic secondary aliphatic amine, reacts with 1,3,5-trimesoyl chloride (TMC) in the interfacial polymerization. The physical characterization of the membranes was performed through different analytical tools like Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle analyzer. The selectivity in separating bivalent and monovalent salts is well observed in this composite membrane. The composite membranes show their potentiality in defluoridation. The rejection profile is ~ 84% for the feed water (pH 6.5) having 10 mg/L fluoride at pressure 1.034 MPa. The influencing parameters (viz. pH, concentration, applied pressure, nature of water matrix) on separation performances are studied.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Proteome-wide Mendelian randomization (MR) shows value in prioritizing drug targets in Europeans but with limited evidence in other ancestries. Here, we present a multi-ancestry proteome-wide MR ...analysis based on cross-population data from the Global Biobank Meta-analysis Initiative (GBMI). We estimated the putative causal effects of 1,545 proteins on eight diseases in African (32,658) and European (1,219,993) ancestries and identified 45 and 7 protein-disease pairs with MR and genetic colocalization evidence in the two ancestries, respectively. A multi-ancestry MR comparison identified two protein-disease pairs with MR evidence in both ancestries and seven pairs with specific effects in the two ancestries separately. Integrating these MR signals with clinical trial evidence, we prioritized 16 pairs for investigation in future drug trials. Our results highlight the value of proteome-wide MR in informing the generalizability of drug targets for disease prevention across ancestries and illustrate the value of meta-analysis of biobanks in drug development.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The present investigation aimed to evaluate antibacterial, antifungal and antioxidant efficacy of essential oils of three commonly used spices (black pepper, cinnamon and clove) in combination along ...with chemical characterization and toxicity evaluation. Among the possible combinations tested, cinnamon/clove oil combination showed synergistic antibacterial activity against foodborne bacteria
Staphylococcus aureus
,
Listeria monocytogenes, Salmonella typhimurium and Pseudomonas aeruginosa
and synergistic antifungal activity against
Aspergillus niger
as well as synergistic antioxidant potential in DPPH radical scavenging model system. GC–HRMS analysis revealed that out of thirteen identified components from clove oil, eugenol was found to be the main constituent of the oil; whereas out of twenty one identified constituents from cinnamon oil, the main component was cinnamaldehyde. Cinnamon/clove oil combination did not show any cytotoxic potential at recommended dosage level (IC
50
> 2000 µg/ml). The results provide evidence that cinnamon/clove oil combination might indeed be used as a potential source of safe and effective novel natural antibacterial, antifungal and antioxidant blend in the food and pharmaceutical industries. To the best of our knowledge, this is the first time a combination of essential oils has been tested as natural preservatives to prevent both microbial proliferation and oxidative deterioration at sufficiently low concentrations.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
With the advancement of industrialisation, pollution is a crucial problem for mankind. In the Green drive, i.e to make the world pollution-free, radiation technology takes an important position. ...Nuclear radiation has made its entry into many chemical processes. ‘Polymerisation’, ‘grafting’ and ‘curing’, all-important chemical processes in the polymer field, can proceed through radiation techniques. The radiation technology is preferred over the other conventional energy resources due to some reasons, e.g. large reactions as well as product quality can be controlled, saving energy as well as resources, clean processes, automation and saving of human resources etc. Apart from this, radiation is also a good sterilising technique over other conventional sterilising techniques. The irradiation of polymers can be applied in various sectors. In this review, the attention has focussed primarily to four sectors, i.e. biomedical, textile, electrical and membrane technology.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
ABSTRACT We report the results of the statistical analysis of planetary signals discovered in MOA-II microlensing survey alert system events from 2007 to 2012. We determine the survey sensitivity as ...a function of planet-star mass ratio, q, and projected planet-star separation, s, in Einstein radius units. We find that the mass-ratio function is not a single power law, but has a change in slope at q ∼ 10−4, corresponding to ∼20 M⊕ for the median host-star mass of ∼0.6 . We find significant planetary signals in 23 of the 1474 alert events that are well-characterized by the MOA-II survey data alone. Data from other groups are used only to characterize planetary signals that have been identified in the MOA data alone. The distribution of mass ratios and separations of the planets found in our sample are well fit by a broken power-law model of the form for q > qbr and for q < qbr, where qbr is the mass ratio of the break. We also combine this analysis with the previous analyses of Gould et al. and Cassan et al., bringing the total sample to 30 planets. This combined analysis yields , n = −0.93 0.13, , and for qbr 1.7 × 10−4. The unbroken power-law model is disfavored with a p-value of 0.0022, which corresponds to a Bayes factor of 27 favoring the broken power-law model. These results imply that cold Neptunes are likely to be the most common type of planets beyond the snow line.
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