Despite the myriad literature reports on the alkaline anion exchange membrane (AAEM) in recent times, the main bottleneck yet to be resolved adequately is the development of a polymer membrane with excellent alkaline stability and high hydroxide conductivity. In order to mitigate these, in this work we have studied the influence of ion yielding alkyl group structure on the improvement of the alkaline stability and hydroxide conductivity of the AAEM with dual ion exchange sites, namely, pyridinium and imidazolium. Three different types of polymers, polybenzimidazole (PBI), pyridine bridged PBI (PyPBI), and tertiary butyl PyPBI (t But -PyPBI), were converted to their iodide forms by alkylation of the imidazole ring by reacting with various kinds of alkyl iodides such as methyl iodide, butyl iodide, and isobutyl iodide. All the iodide forms of polybenzimidazolium membranes were transformed into the hydroxide form so as to obtain an AAEM by immersing them in KOH solution. FT-IR and 1 H NMR spectroscopic studies were employed to confirm the structure of polymer, iodide forms, and KOH-loaded AAEM of all three PBI structures studied here. Ion exchange capacity (IEC), hydroxide conductivity, and thermal, mechanical, and alkaline stability of all the membranes were studied, and we found that PyPBI alkylated with butyl iodide (PyPBI-BuI) has the highest IEC, 3.37 mequiv/g, and maximum hydroxide conductivity, 128.6 mS/cm, at 80 °C among all the membranes developed in this work. All the membranes, irrespective of the polymer structure, when alkylated with isobutyl and butyl chain displayed excellent alkaline stability even in 5 M KOH aqueous solution up to 60 °C, whereas when alkylated with methyl iodide all the membranes showed poor alkaline stability even in 1 M KOH at room temperature. This observation showed the importance of the alkylated moieties structure on the alkaline stability of the AAEM. This significant stability may be due to the bulky nature of the alkyl moieties, which prevented the hydroxide ion attack on both pyridinium and imidazolium groups. Further, our computational studies using DFT calculations confirmed that the electronic factors are the major driving forces rather than the steric hindrance for such high alkaline stability in the case of longer (isobutyl, butyl) alkylated chains, particularly in the case of PyPBI and t But -PyPBI.

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Infectious keratoconjunctivitis (IKC) is a highly contagious ocular inflammatory condition, which is often reported in domestic small and large ruminants. Multiple infectious aetiologies are reported to be involved, but information about the role of certain fastidious bacterial pathogens such as chlamydiae and mycoplasmas is limited in India. Hence, this study was performed to determine the role of these pathogens and their identification by molecular approach. A total of 53 samples from 31 ovine, 14 caprine and eight bovine having clinical symptoms were collected and tested using species-specific PCR tests for chlamydiae and mycoplasmas followed by nucleotide sequence analysis. The results showed 77.41, 14.29 and 25% samples were chlamydiae positive in ovine, caprine and bovine, respectively, whereas 41.93, 14.29 and 37.5% prevalence of mycoplasma infection was detected in ovine, caprine and bovines, respectively. Chlamydophila abortus, Chlamydophila psittaci, Mycoplasma arginini and Mycoplasma hyorhinis were detected from tested samples. To the best of our knowledge, this is the first time these species are identified in IKC cases from India. Coinfection of both chlamydial and mycoplasmal species was detected in eight IKC cases of ovine which suggest synergistic roles played by both chlamydiae and mycoplasma in IKC samples.

The present study was undertaken to assess the fertility status of soil put under various cropping sequences followed in different villages of different blocks in the district. Seven villages namely Bhagwanpur, Bhetan, Boolpur, Kheeranwali, Khukrain, Meripur and Swal, falling under three blocks namely Dhilwan, Kapurthala and Sultanpur were selected. The soil samples were taken from 0-15 cm depth with the help of auger after the harvesting of the rabi crops during 2014-15, using the GPS locations. The pH values of soils in all the villages varied from neutral to strongly alkaline (6.79 to 9.87). The pH of all the soil samples of Bhagwanpur and Bhetan villages was neutral to slightly alkaline in nature (<8.7), however, the highest mean pH value was from village Khukrain where 31 per cent of the soil samples were found to be strongly alkaline (>9.3) followed by Kheeranwali village (15 %). The salinity hazard does not exist in village Bhagwanpur, Meripur and Bhetan, however, 42 and 36 per cent samples in village Khukrain and Boolpur showed higher salinity level, respectively. The mean value of EC in Boolpur was 0.76ds/m with a range varying from 0.3 to 1.9ds/m. It was found that organic carbon (OC) status of majority of samples ranged between low to medium. In light textured soils, 54 per cent of samples of Bhetan were found to contain low OC content whereas the soils of Boolpur were found to be rich in OC ranging from 0.32 to 1.07 per cent with mean value of 0.64 per cent and only 12 per cent of samples were under low OC category. The mean values of available phosphorus were 16.7 to 24.2 kg/ha in soil samples of all the villages. The high status of available potassium was found in Khukrain village (92%) followed by Bhagwanpur (72%), Kheeranwali (55%), Swal and Bhetan (45%) and Boolpur (44%). It was interested to note that highest available phosphorus content was found in the soil under potato based cropping sequence due to excessive phosphatic fertilizers application as compared to recommendations of research institutes. However, contrast trends were obtained in case of available potassium status because uptake of potassium was low in paddy-wheat cropping sequence as compared to vegetable and potato based cropping sequence. The OC and available phosphorus exhibited a positive correlation with cropping intensity due to application of higher inorganic fertilizers and incorporation of plant biomass as compared to paddywheat cropping sequence. On the other hand, pH, EC and available potassium showed a decreasing trend with the increased crop intensity from paddy-wheat to paddy-potato/vegetable-summer crop.

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