Electrostatic Correlations Lead to High Capacitance in Zwitterion-Containing Thin Films.

A novel zwitterion composed of an imidazolium tethered to an anionic sulfonyl(trifluoromethane sulfonyl)imide group was prepared as an alternative dielectric material to traditional ionic liquids. The zwitterion not only melted below 100 °C but also proved to be nonhygroscopic. High-capacitance organic dielectric materials were obtained by blending this compound with poly(methyl methacrylate) over a range of concentrations and thicknesses.

Scalable Non-Halogenated Co-solvent System for Large-Area, Four-Layer Slot-Die-Coated Organic Photovoltaics.

Sustainable processing solvents, photoactive materials, and scalable manufacturing will play a key role in commercializing printed organic photovoltaics (OPVs). The record-breaking pioneering OPV reports have done an outstanding job in accelerating the discovery of champion photoactive materials and device engineering practices; however, these works predominantly involve health-hazardous halogenated processing solvents/additives and non-scalable thin-film coating methods. Herein, large-area slot-die-manufactured OPV cells from eco-friendly halogen-free solvents and synthetically scalable materials are showcased.

Quantification of excess Carbon-14 specific activity in terrestrial biota in the off-site locations of the PHWR nuclear power plant at Kaiga, India.

This is the first detailed study on C activity in the environment surrounding a nuclear facility in India. Samples of food matrices and wild plants from the off-site locations of the PHWR nuclear power plant (NPP) at Kaiga were analysed by liquid scintillation spectrometry, results were validated by accelerator mass spectrometry, and an extensive database (N = 142) was established. The stable isotope ratio of carbon (δC) in terrestrial plants varied from -33.

Carbon-14 emission from the pressurized heavy water reactor nuclear power plant at Kaiga, India.

This is a detailed study on oxide (CO) and reduced (hydrocarbons, CH) forms of C releases through gaseous effluents from the Kaiga nuclear power plant (NPP), on the West Coast of India, where 4 × 220 MW(e) pressurized heavy water reactors (PHWRs) are operating. The gaseous effluent from the common stack of reactor units 3 and 4 (each of 220 MW(e)) was sampled from 2017 to 2020 for C activity monitoring and analysed for C activity by liquid scintillation counting. The normalized release rate corresponding to the four-year monitoring period had a geometric mean value of 0.

NE-OBT and TFWT activity concentrations in wild plants in the vicinity of the PHWR nuclear power plant and control regions of the tropical monsoonal climatic region of the Indian subcontinent.

The results of the first detailed study, involving a large number of samples, on water equivalent factor (WEQ), non-exchangeable organically bound tritium (NE-OBT) and tissue free water tritium (TFWT) activity concentrations in predominant plant species of the tropical monsoonal climatic region, are presented. A total of 369 samples from the vicinity of the PHWR nuclear power plant (NPP) at Kaiga, West Coast of India, and 47 samples of the control region (region not affected by local anthropogenic sources) were analysed. The WEQ varied in the range of 0.

Optimisation of CO absorption and liquid scintillation counting method for carbon-14 specific activity measurement in atmospheric air.

A method for the determination of C activity in the ambient air was optimised with the development of a simple setup for the regeneration of CO from carbonate sample and saturating the absorber in <45 min for direct determination of activity by liquid scintillation counting (LSC). Atmospheric CO was trapped in NaOH solution and precipitated as BaCO by adding BaCl. The carbonate sample was taken in a newly designed regeneration system, subjected to acid hydrolysis, and the absorber (CarboSorb-E) was saturated with the CO regenerated from carbonate sample.

Experimental database on water equivalent factor (WEQ) and organically bound tritium activity for tropical monsoonal climate region of South West Coast of India.

Tritium in the form of tritiated water is easily incorporated into terrestrial biota as tissue free water tritium (TFWT). A part of TFWT is converted into organically bound tritium (OBT) through metabolic processes. For the computation of NE-OBT activity (expressed as Bq L of combustion water) in terrestrial plants, knowledge on 'water equivalent factor (WEQ)', defined as the volume of water produced from the combustion of 1 kg of the dry sample, is essential.

Optimisation of a batch thermal combustion method using a tube furnace oxidation system (pyrolyser) and LSC for carbon-14 determination in environmental matrices.

Accelerator mass spectrometry and benzene synthesis coupled with liquid scintillation spectrometry are often used for accurate measurements of C activity in the environmental matrices. Thermal oxidation is one of the methods employed for C determination in environmental matrices. In this method, the sample is oxidised at high temperature (600-900 °C) to convert carbon species to CO and trapped in an amine-based absorber for determining the activity in a liquid scintillation counting (LSC) system.

Determination of Organically Bound Tritium (OBT) Concentration in Fish by Thermal Oxidation and Liquid Scintillation Counting Method.

Effluents containing tritium (H) dispersed into the fresh water or marine environment from nuclear facilities can be taken up by biota. Aquatic and marine organisms are among the important pathways through which tritium can enter into the human body, and hence, assessment of the extent of pollution of these ecosystems is very important for radiation dose assessments. Tritium present in environmental matrices can be classified as tissue-free water tritium (TFWT) and organically bound tritium (OBT).

A WALK-IN TYPE CALIBRATION CHAMBER FACILITY FOR 222Rn MEASURING DEVICES AND INTER-COMPARISON EXERCISES.

A walk-in type 222Rn calibration chamber of volume 22.7 m3, which has traceability to international standards, is established at the Centre for Advanced Research in Environmental Radioactivity, Mangalore University, India. It has a human-machine interface communication system, a programmable logic controller and sensor feedback circuit for controlling and data acquisition of relative humidity (RH) and temperature (T).

A study of temporal variations of Be and Pb concentrations and their correlations with rainfall and other parameters in the South West Coast of India.

As a part of establishing a regional database on natural radioactivity, the atmospheric concentrations of Pb and Be were measured over a three and half year period (2014-2017) in Mangalore and Kaiga in the South West Coast of India. A total of 99 air samples, collected in the different months of the year, were analysed in this study. The mean activity concentrations of Be and Pb were found to be 5.

Controlling cellular activity by manipulating silicone surface roughness.

Silicone elastomers exhibit a broad range of beneficial properties that are exploited in biomaterials. In some cases, however, problems can arise at silicone elastomer interfaces. With breast implants, for example, the fibrous capsule that forms at the silicone interface can undergo contracture, which can lead to the need for revision surgery.

Biocompatible, hyaluronic acid modified silicone elastomers.

Although silicones possess many useful properties as biomaterials, their hydrophobicity can be problematic. To a degree, this issue can be addressed by surface modification with hydrophilic polymers such as poly(ethylene glycol), but the resulting structures are usually not conducive to cell growth. In the present work, we describe the synthesis and characterization of covalently linked hyaluronic acid (HA) (35 kDa) to poly(dimethylsiloxane) (PDMS) elastomer surfaces.