Mapping the magnetic field in the solar corona through magnetoseismology

Science China Technological Sciences - Magnetoseismology, a technique of magnetic field diagnostics based on observations of magnetohydrodynamic (MHD) waves, has been widely used to estimate the...     

Solar ultraviolet bursts in a coordinated observation of IRIS,Hinode and SDO

Solar ultraviolet(UV) bursts are small-scale compact brightenings in transition region images. The spectral profiles of transition region lines in these bursts are significantly enhanced and broadened, often with chromospheric absorption lines such as Ni ii 1335.203 and 1393.330 ? superimposed. We investigate the properties of several UV bursts using a coordinated observation of the Interface Region Imaging Spectrograph(IRIS), Solar Dynamics Observatory(SDO), and Hinode on February 7, 2015. We have identified 12 UV bursts, and 11 of them reveal small blueshifts of the Ni ii absorption lines. However, the Ni ii lines in one UV burst exhibit obvious redshifts of ～20 km s~(-1), which appear to be related to the cold plasma downflows observed in the IRIS slit-jaw images. We also examine the three-dimensional magnetic field topology using a magnetohydrostatic model, and find that some UV bursts are associated with magnetic null points or bald patches. In addition, we find that these UV bursts reveal no obvious coronal signatures from the observations of the Atmospheric Imaging Assembly(AIA) on board SDO and the EUV Imaging Spectrometer(EIS) on board Hinode.     

Microstructure and mechanical properties of copper alloyed austempered grey cast iron

Austempered grey cast iron (AGI) has emerged as a major engineering material in recent years because of its attractive mechanical properties. The main aim of this investigation is to assess the mechanical properties of copper alloyed AGI. Alloyed grey cast iron specimens are subjected to austempering heat treatment at six different temperatures for four different time periods. The resulting microstructures have been evaluated and characterised by means of light microscope and scanning electron microscope and X-Ray diffraction analysis. The microstructural features of AGI such as austenite content and its carbon content have been also found to influence the hardness, tensile properties and elongation. Both duration of the austempering time and the austempering temperature affect the mechanical properties of AGI. The hardness, tensile strength and ductility initially increase, and thereafter it decreases on longer periods of austempering. On the other hand hardness, tensile strength decreases as increasing austempering temperature, while ductility increases. The best combination of hardness 380BHN and strength 332?MPa; observed at 927°C of austenitising and 260°C of austempering temperature for 60?min.     

Inducing Personalities and Values from Language Use in Social Network Communities

A community in social networks is generally assumed to be composed of a group of individuals with similar characteristics. Although there has been a plethora of work on understanding network topologies (edge density, clustering coefficient, etc.) within an online community, the psycho-sociological compositions of social network communities have hardly been studied. The present paper aims to analyse the communities as composition of induced psycholinguistic and sociolinguistic variables (Personalities, Values and Ethics) across individuals in social media networks. The motivation behind this analysis is to understand the behavioural characteristics at individual as well as societal level in social networks. To this end, three studies were carried out on six different datasets: three Twitter corpora, two Facebook corpora, and an Essay corpus, annotated with Values and Ethics of the users. First, experiments on creating automatic models to determine the Personality and Values of individuals by analysing their language usage and social media behaviour. Second, experiments on understanding the characteristics or blend of characteristics of individuals within an online community. Finally, generation of a map of values and ethics for India, a multi-lingual and multi-cultural country. Striking similarities to general intuitive perception could be observed, i.e., the results obtained in the study resemble our general perception about the cities/towns of India.     

Analytical moment based approximation for robust design optimization

The role of robust design optimization (RDO) has been eminent, ascertaining optimal configuration of engineering systems in the presence of uncertainties. However, computational aspect of RDO can often get tediously intensive in dealing with large scale systems. To address this issue, hybrid polynomial correlated function expansion (H-PCFE) based RDO framework has been developed for solving computationally expensive problems. H-PCFE performs as a bi-level approximation tool, handling the global model behavior and local functional variation. Analytical formula for the mean and standard deviation of the responses have been proposed, which reduces significant level of computations as no further simulations are required for evaluating the statistical moments within the optimization routine. Implementation of the proposed approaches have been demonstrated with two benchmark examples and two practical engineering problems. The performance of H-PCFE and its analytical version have been assessed by comparison with direct Monte Carlo simulation (MCS). Comparison with popular state-of-the-art techniques has also been presented. Excellent results in terms of accuracy and computational effort obtained makes the proposed methodology potential for further large scale industrial applications.     

Chaos,intermittency and control of bifurcation in a ZC2-DPLL

Nonlinear dynamics of a dual sampler-based zero crossing digital phase lock loop (ZC₂-DPLL) has been investigated. Analysis supported by detailed numerical studies shows that the system enters a chaotic state through a cascade of period doubling bifurcation. The dynamics of the system have been quantified with the dynamical measures of Lyapunov exponent and correlation dimension. Further, it has been found that for certain system parameters intermittency occurs in the system. The occurrence of intermittency has been proved using the Pomeau–Manneville principle. The phenomenon of bifurcation control in a ZC₂-DPLL using time delay feedback has been explored. It has been found that for some suitably chosen control parameters bifurcation phenomena can be controlled such that the stable locked zone of a bifurcation controlled ZC₂-DPLL can be extended, which enhances the application potentiality of a ZC₂-DPLL.     

Acid‐Controlled Chemodivergent Synthesis of Three Differently Substituted Quinolines via Site Selective Coupling of ortho‐ Aminoaryl Ketones with α‐Enolic Dithioesters

A straightforward approach for the chemodivergent synthesis of quinolines is described through site‐selective coupling of ortho‐aminoaryl ketones with α‐enolic dithioesters (DTEs) under solvent‐free conditions. The operationally and user‐simple one‐pot methodology is based on the trifunctional nature of DTEs. Both the carbonyl and the thiocarbonyl moiety in α‐enolic dithioesters were employed for the efficient construction of three differently substituted quinolines in a chemoselective manner simply by variation of an easy to handle acid catalyst.

     

Micronutrients (B,Co, Cu,Fe, Mn,Mo, and Zn) content in made tea (Camellia sinensis L.) and tea infusion with health prospect: A critical review

Tea (Camellia sinensis L.) is a perennial acidophilic crop, and known to be a nonalcoholic stimulating beverage that is most widely consumed after water. The aim of this review paper is to provide a detailed documentation of selected micronutrient contents, viz. boron (B), cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), and zinc (Zn) in made tea and tea infusion. Available data from the literature were used to calculate human health aspect associated with the consumption of tea infusion. A wide range of micronutrients reported in both made tea and tea infusion could be the major sources of micronutrients for human. The content of B, Co, Cu, Fe, Mn, Mo, and Zn in made tea are ranged from 3.04 to 58.44 μg g^?1, below detectable limit (BDL) to 122.4 μg g^?1, BDL to 602 μg g^?1, 0.275 to 13,040 μg g^?1, 0.004 to 15,866 μg g^?1, 0.04 to 570.80 μg g^?1 and 0.01 to 1120 μg g^?1, respectively. Only 3.2 μg L^?1 to 7.25 mg L^?1, 0.01 μg L^?1 to 7 mg L^?1, 3.80 μg L^?1 to 6.13 mg L^?1, 135.59 μg L^?1 ?11.05 mg L^?1, 0.05 μg L^?1 to 1980.34 mg L^?1, 0.012 to 3.78 μg L^?1, and 1.12 μg L^?1 to 2.32 μg L^?1 of B, Co, Cu, Fe, Mn, Mo, and Zn, respectively, are found in tea infusion which are lower than the prescribed limit of micronutrients in drinking water by World Health Organization. Furthermore, micronutrient contents in tea infusion depend on infusion procedure as well as on the instrument used for analysis. The proportion of micronutrients found in different tea types are 1.0–88.9% for B, 10–60% for Co, 2.0–97.8% for Cu, 67.8–89.9% for Fe, 71.0–87.4% for Mn, 13.3–34% for Mo, and 34.9–83% for Zn. From the results, it can also be concluded that consumption of three cups of tea infusion per day does not have any adverse effect on human health with respect to the referred micronutrients rather got beneficial effects to human.     

Microbe-mediated biodegradation of microplastics from wastes

Microplastics (MPs) with slow degradation rates carry toxins and pathogens from surroundings, accumulate and pollute the environment. They bio-accumulate on humans and other lifeforms leading to health concerns, including inflammatory lesions, oxidative stress and increased cancer risk, thus requiring immediate remediation actions. This review summarizes, categorizes and analyses recent findings on MP source, transit and environmental toxicity and explores their microbe-mediated breakdown. Various micro-organisms such as fungi, bacteria, algae and protists interact with and build biofilm on MP surfaces and alter their surface morphology for their degradation. Pure strains and microbial consortia have been successfully able to degrade MPs. Extracellular enzymes are produced by these micro-organisms that convert the complex recalcitrant polymeric structure of MP to simpler forms. Further, knowledge of factors associated with MP degradation along with the development of genetic tools enhances the rate of microbial degradation with consortium having an advantage over single bacterium-mediated MP transformation, which has been discussed.