Effect of Ionic Liquid on the Properties of Nanocomposites Based on Epoxy/CNT Hardened with MCDEA

Thermosetting systems based on epoxy resin (RE) with the dispersion of carbon nanotubes (CNT), have been extensively studied by the development of high-performance materials with interesting mechanical, thermal and electrical properties that the thermo-rigid system achieves with the addition of CNT, and thus contribute to obtain composites with excellent performance in low amounts of this filler. However, ensuring a good dispersion of these systems is not easy, as CNTs have a great tendency to cluster due to Van der Waals interactions. To assist in the dispersion of the systems, a phosphonium-based ionic liquid, tributyl (ethyl) -phosphonium diethyl phosphate, acted with a double role, as a dispersion agent and catalyst in systems hardened with MCDEA (4,4’-methylenebis (3 - chloro-2,6-diethylaniline), which is a solid compound giving the systems high viscosity, and with the addition of LI improved the dispersion of the systems, as well as the processability in the preparation of the nanocomposites.

Biosensors for Detection of Organophosphate Exposure by New Diethyl Thiophosphate-Specific Aptamer

Objective An aptamer specifically binding to diethyl thiophosphate (DETP) was constructed and incorporated in an optical sensor and electrochemical impedance spectroscopy (EIS) to enable the specific measurement of DETP as a metabolite and a biomarker of exposure to organophosphates. Results DETP-bound aptamer was selected from the library using capillary electrophoresis-systematic evolution of ligands by exponential enrichment (CE-SELEX). A colorimetric method revealed the aptamer had the highest affinity to DETP with a mean Kd value (± SD) of 0.103 ± 0.014 µM. Changes in resistance using EIS showed selectivity of the aptamer for DETP higher than for dithiophosphate (DEDTP) and diethyl phosphate (DEP) which have similar structure and are metabolites of some of the same organophosphates. The mean (± SD) of percentage of altered resistance of DETP was calculated at 47.5 ± 8.8% which was significantly higher than of DEDTP at 14.3 ± 1.5% and of DEP at 7.0 ± 1.4%. Conclusions The current method showed a great promise in using the DETP-specific aptamer to detect the exposure history to organophosphates, by measuring their metabolite, although degradation of organophosphate parent compounds might occur.

A recurring disease outbreak following litchi fruit consumption among children in Muzaffarpur, Bihar—A comprehensive investigation on factors of toxicity

Litchi fruits are a nutritious and commercial crop in the Indian state of Bihar. Litchi fruit contains a toxin, methylene cyclopropyl-glycine (MCPG), which is known to be fatal by causing encephalitis-related deaths. This is especially harmful when consumed by malnourished children. The first case of litchi toxicity was reported in Bihar in 2011. A similar event was recorded in 2014 among children admitted to the Muzaffarpur government hospital, Bihar. Litchi samples sent to ICMR-NIN were analyzed and MCPG was found to be present in both the pulp and seed of the fruit. Diethyl phosphate (DEP) metabolites were found in the urine samples of children who had consumed litchi fruit from this area indicating exposure to pesticide. The presence of both MCPG in litchi and DEP metabolites in urine samples highlights the need to conduct a comprehensive investigation that examines all factors of toxicity.

Poly[3-ethyl-1-vinyl-imidazolium] diethyl phosphate/Pebax® 1657 Composite Membranes and Their Gas Separation Performance

Poly(ionic liquid)s are an innovative class of materials with promising properties in gas separation processes that can be used to boost the neat polymer performances. Nevertheless, some of their properties such as stability and mechanical strength have to be improved to render them suitable as materials for industrial applications. This work explored, on the one hand, the possibility to improve gas transport and separation properties of the block copolymer Pebax® 1657 by blending it with poly[3-ethyl-1-vinyl-imidazolium] diethyl phosphate (PEVI-DEP). On the other hand, Pebax® 1657 served as a support for the PIL and provided mechanical resistance to the samples. Pebax® 1657/PEVI-DEP composite membranes containing 20, 40, and 60 wt.% of PEVI-DEP were cast from solutions of the right proportion of the two polymers in a water/ethanol mixture. The PEVI-DEP content affected both the morphology of the dense membranes and gas transport through the membranes. These changes were revealed by scanning electron microscopy (SEM), time-lag, and gravimetric sorption measurements. Pebax® 1657 and PEVI-DEP showed similar affinity towards CO2, and its uptake or solubility was not influenced by the amount of PIL in the membrane. Therefore, the addition of the PIL did not lead to improvements in the separation of CO2 from other gases. Importantly, PEVI-DEP (40 wt.%) incorporation affected and improved permeability and selectivity by more than 50% especially for the separation of light gases, e.g., H2/CH4 and H2/CO2, but higher PEVI-DEP concentrations lead to a decline in the transport properties.

Monitoring of the evaluation of winter garlic morphometry using chemical mutagens

The results of treatment of winter garlic that is grown in the Crimea with chemical mutagens are presented. The air bulbs (garlic bulbs) of the local population were treated with chemical mutagens of the first group (they are capable to transfer alkyd compounds to other molecules), namely, diethyl phosphate 0.025%, 0.05 and 0.1%, as well as dimethyl sulfate 0.025%, 0.04 and 0.08%. In the first year of harvest, cloves of garlic were divided into large Ø 2.5-3 cm, medium - from 1.5 to 2.5 cm and small ones - less than 1.5 cm. Then (in 2017-2018), plant morphometry was monitored. A change in morphological features was revealed: an increase in plant height by 9- 19% and the number of leaves up to 25% (with an increase in their length and a decrease in width). Depending on the group of plants, a decrease in the height of the false stem to 21% was noted with a significant increase in its diameter. An increase in the diameter of the bulbs by 14 -19%, depending on the concentration of the mutagen and the group of plants, was revealed. Treatment of air bulbs of winter garlic with chemical mutagens (diethyl phosphate and dimethyl sulfate) made it possible to select the healthy garlic cloves with a weight up to 24-32 g with an increased reproduction rate (6) in a group of plants marked as “large ”.