Effect of Cathode Microstructure on Electrochemical Properties of Sodium Nickel-Iron Chloride Batteries

Sodium metal chloride batteries have become a substantial focus area in the research on prospective alternatives for battery energy storage systems (BESSs) since they are more stable than lithium ion batteries. This study demonstrates the effects of the cathode microstructure on the electrochemical properties of sodium metal chloride cells. The cathode powder is manufactured in the form of granules composed of a metal active material and NaCl, and the ionic conductivity is attained by filling the interiors of the granules with a second electrolyte (NaAlCl4). Thus, the microstructure of the cathode powder had to be optimized to ensure that the second electrolyte effectively penetrated the cathode granules. The microstructure was modified by selecting the NaCl size and density of the cathode granules, and the resulting Na/(Ni,Fe)Cl2 cell showed a high capacity of 224 mAh g−1 at the 100th cycle owing to microstructural improvements. These findings demonstrate that control of the cathode microstructure is essential when cathode powders are used to manufacture sodium metal chloride batteries.

Histopathological changes in the gills of zebrafish (Danio rerio) and bullfrog tadpoles (Lithobates catesbeianus) caused by the use of formaldehyde

Formaldehyde is a carcinogenic and aggressive agent mainly to epithelial tissues. However, for rearing aquatic organisms its use is common for the treatment of fungi and parasites, and the use of incorrect doses can harm the health and life of these animals. The fish species Danio rerio and the tadpoles of the species Lithobates catesbeianus are internationally recognized for use in aquatic toxicology tests. We aimed identify the effects caused by formaldehyde on the gills of these two experimental models used in aquatic toxicology, verifying the susceptibility of both species. Acute and chronic tests with formaldehyde were conducted for experiment. We found that the formaldehyde in the higher concentration caused injuries to the gills of both fish and tadpoles, with a loss and displacement of epithelium, vascular congestion, telangiectasia and lamellar epithelial lifting/edema (possible aneurysm), hyperplasia and hypertrophy of epithelial cells, lamellar fusion in addition to the proliferation of mucus-secreting cells and chloride cells. Despite structural differences, the histological changes caused by chronic exposure to formaldehyde in sublethal concentrations were similar in both organisms and we recommend reviewing its use in prophylaxis and in prolonged treatments with this chemical.

The Effect of Different Salinity Levels on Chloride Cells of Periophthalmus Waltoni’s Epidermis in Connection with NA + / K + / ATPase ion Transporter and NA + / K + / 2CL Cotransporter using Immunohistochemistry Technique

Background: The NA+ / K+ / ATPase and NA+ / K+ / 2CL cotransporter are two types of ions transporting proteins that are active in the secretion of chloride in bony fish. So, the level and activity of these transporting proteins are expected to increase in saline water. The aim of this study was to investigate the effect of different salinity levels on chloride cells of Periophthalmus waltoni’s epidermis in connection with NA+ / K+ / ATPase ion transporter and NA+ / K+ / 2CL cotransporter using immunohistochemistry technique.Results: Simultaneous localization of NA+ / K+ / ATPase and NA+ / K+ / 2CL cotransporter showed that both were simultaneously present in epidermal ion cells and were able to react to different salinity levels. Conclusion: The results of this study confirmed the model that states, NA+ / K+ / ATPase and NA+ / K+ / 2CL cotransporters are responsible for the secretion of chloride from the chloride cells of bony fish.

Optimal Composition of Chloride Cells for Osmoregulation in a Randomly Fluctuating Environment

Fish live in water with a different osmotic pressure from that in the body. Their gills have chloride cells that transport ions to maintain an appropriate level of osmotic pressure in the body. The direction of ion transport is different between seawater and freshwater. There are two types of chloride cells that specialize in unidirectional transport and generalist cells that can switch their function quickly in response to environmental salinity. In species that experience salinity changes throughout life (euryhaline species), individuals may replace some chloride cells with cells of different types upon a sudden change in environmental salinity. In this paper, we develop a dynamic optimization model for the chloride cell composition of an individual living in an environment with randomly fluctuating salinity. The optimal solution is to minimize the sum of the workload of chloride cells in coping with the difference in osmotic pressure, the maintenance cost, and the temporal cost due to environmental change. The optimal fraction of generalist chloride cells increases with the frequency of salinity changes and the time needed for new cells to be fully functional but decreases with excess maintenance cost.

Effects of Salinity on Gills’ Chloride Cells, Stress Indices and Gene Expression of Asian Seabass (Lates Calcarifer, Bloch, 1790)

A two-week research was carried-out to assess water salinity (WS) effects including 0, 15, 35 and 50‰ on osmoregulatory mechanisms and stress indices in Asian sea bass (34.4 g) juveniles. Except for fish reared at 50‰, in the other treatments gradually decreased to the prescribed WS during a 10-day period (-5‰ a day). After 10-day of acclimation period, fish reared at the prescribed WS for two weeks. Fish reared at 15 and 35‰ had higher chloride cell (CC) counts in the interlamellar region. The number of CC in the interlamellar region elevated with increment of WS up to 35‰, but they were pronouncedly reduced in 50‰ group . The diameter of CC in the interlamellar region was not affected by WS. The least nucleus diameter of CC in the interlamellar region was observed in fish reared at 15‰ (P < 0.05). The greatest and the least amounts of serum aspartate aminotransferase content were observed in fish reared at freshwater and 15‰, respectively. Fish reared at 35‰ had the highest serum sodium and potassium contents. Serum chloride content and total osmolality increased with increment of WS (P < 0.05). Serum cortisol and glucose contents gradually increased with elevation of WS up to 35‰, then their contents remarkably decreased. The relative expression of insulin like growth factor-1 in the liver of fish reared at 35‰ was strikingly higher than the other groups. The relative expression of HSP70 gene in fresh water group was pronouncedly elevated compared to other treatments. The relative expression of interleukin-1β in 15 and 35‰ groups was higher than the other groups; however, the relative expression of lysozyme gene in the liver of fish reared at fresh water was pronouncedly lower than the other treatments. The results of this study suggested rearing L. calcarifer at 15‰ closer to the isosmotic point and better provide its welfare.

First instar nymphs of two peltoperlid stoneflies (Insecta, Plecoptera, Peltoperlidae)

The first instar nymphs of two peltoperlid stoneflies, i.e., Microperla brevicauda Kawai, 1958 of Microperlinae and Yoraperla uenoi (Kohno, 1946) of Peltoperlinae, were examined and described. Additionally, the phylogeny and groundplan of the first instar nymphs of Peltoperlidae and Plecoptera were considered. The first instar nymphs of M. brevicauda have a slender body with a prognathous head of typical shape; they represent a groundplan in Plecoptera. On the other hand, the first instar nymphs of Y. uenoi have a broad, cockroach-like body with an orthognathous and shortened head, the latter being regarded as a potential autapomorphy of Peltoperlinae. Such differences in body shape between the subfamilies are speculated to arise from heterochrony. The three-segmented cerci of Y. uenoi are characteristic to Systellognatha, whereas the four-segmented cerci of M. brevicauda were independently acquired within Microperlinae. The structure and distribution pattern of chloride cells in the first instar nymphs of Plecoptera were also discussed. The presence of coniform chloride cells is a potential groundplan of Arctoperlaria. One to two pairs of chloride cells are distributed on the first nine abdominal segments of M. brevicauda; this represents a groundplan character of Systellognatha. On the other hand, one to four pairs of chloride cells are found on the second to ninth abdominal segments of Y. uenoi; this distribution pattern may be an apomorphic groundplan of Peltoperlinae.