Temperature-dependent study of AcFc-FeIII(acac)3 redox couple for non-aqueous redox flow battery

This article describes the temperature dependence electrochemical analysis of acetyl ferrocene (AcFc) and iron(III) acetylacetonate ([Fe(acac)3]) for non-aqueous redox flow batteries. An electrochemical cell consisting of AcFc and ([Fe(acac)3]) as catholyte and anolyte species, respectively, were constructed with a cell voltage of 1.41 V and Coulombic efficiencies >99% for up to 50 total cycles at 25o C (RT) and 0o C. Rotating ring disk electrode (RRDE) experiments suggest that diffusion coefficient decreases as the temperature decreases but overall storing capacity far better than aqueous redox flow battery (ARFBs). The electrochemical kinetic rate constant (k0) of AcFc was found larger than Fe(acac)3 but remains similar at both temperatures. NMR study shows no structural change in changing temperature and after battery experiments

Doping in TiO2 to improve solar cell efficiency: A Comprehensive Review

To enhance the performance and stability of these solar cells, doping of titanium dioxide (TiO2) with elements such as aluminum (Al), neodymium (Nd), and samarium (Sm) has been explored. This abstract provides a summary of the properties affected by Al, Nd, and Sm doping in TiO2 and their impact on DSSCs and PSCs. Al, Nd, and Sm doping in TiO2 have shown improvements in various properties critical to solar cell performance. The reduction of non-stoichiometric oxygen-induced defects through doping results in the removal of deep electronic traps and sub-bandgap states, leading to an increase in the conduction band. This modification contributes to enhanced charge transport and reduced recombination rates within solar cell devices. Furthermore, the doping process facilitates the passivation of oxygen defects, which plays a crucial role in improving the stability of PSCs. Nd doping has shown promising results in enhancing device stability without compromising short-circuit current. The simple and scalable processing techniques employed for doping TiO2 with these elements make them viable for large-scale production. The achieved efficiencies in DSSCs and PSCs vary depending on the specific calculation methods used, including preconditioning bias, voltage scan speed, and direction. Nevertheless, studies have reported significant efficiency improvements with optimal doping concentrations. For instance, a maximum efficiency of 18.2% was recorded in PSCs with 0.3% Nd doping in TiO2, where maximum values for current density (JSC), open-circuit voltage (VOC), and fill factor (FF) were obtained

Morphological relationships, growth patterns and some aspects of reproductive biology of Sind Danio Devario devario (Hamilton 1822)

This study examined the morphological relationships, growth population factors and reproductive biology of Devario devario collected from the Atrai River of Dinajpur, Bangladesh, for sustainable management and conservation aspects. The length-weight relationships (LWRs) commonly indicated the isometric growth. The Fulton’s condition factor (CFf) and relative body weight (BWr) varied across sexes. A positive correlation was found in length-length relationships (LLRs); among total length (TL), standard length, head length and fork length. The asymptotic lengths were 7.5, 7.2 and 7.5 cm, with growth rates of 0.78‒1.8, 0.6‒3.4 and 1.8‒3.6 year–1 while total mortality was 1.22‒3.06, 0.97‒7.07 and 3.70‒6.09 year–1; fishing mortality was –0.87 to –1.04, –0.97 to 1.09 and –0.05 to –0.23 year–1; natural mortality was 2.26–3.93, 1.94–5.98 and 3.93–6.14 year–1 for female, male and combined sexes respectively. The highest probability of capture (L50) was 5.74‒6.15 cm. The gonado-somatic index ranged from 32.75±1.82 to 44.12±2.73, with a peak in April to May. Fecundity was recorded from 3253±289 to 4831±342, with a significant correlation among TL, BW, gonad length (GL) and gonad weight (GW). These initial findings on D. devario will serve as the basis for future research and management

Evaluation of production performance and profitability of hybrid red tilapia and genetically improved farmed tilapia (GIFT) strains in the carbon/nitrogen controlled periphyton-based (C/N- CP) on-farm prawn culture system in Bangladesh

Performance of hybrid red tilapia (Mutant, Oreochromis niloticus × Oreochromis mossambicus) and GIFT tilapia strain (Oreochromis niloticus) in C/N-CP prawn (Macrobrachium rosenbergii) farming system was evaluated at the farmers' pond at Bailor union under Trishal upazilla of Mymensingh district, Bangladesh. The on-farm trial had two treatments: TR and TG (named according to the tilapia strains) with three replications. Six rectangular ponds of varying sizes (400–880 m2) were used for this experiment. Hybrid red and GIFT tilapia stains were stocked with prawn at the stocking densities of 1 tilapia fingerlings (either red or GIFT strain) and 3 prawn juveniles m-2 in both treatments. Bamboo side shoot were posted vertically as periphyton substrate. This resulted in an additional substrate surface area of 1067 m2 for periphyton development equaling 147% of the pond surface area. Considering the body weight of freshwater prawn only, feeding rates were 10% of body weight at the beginning of the study (up to 30 days), and feeding application was gradually reduced to 3% in the last month assuming 80% survival. The abundance of total benthos and periphyton as well as total periphytic biomass were significantly higher (P < 0.05) in TR than TG treatment and they were also differed significantly (P < 0.05) among different months with a decreasing trends (exception to some extent) over the experimental period. The individual harvesting weight, individual weight gain, specific growth rate, Food Conversion Ratio (FCR), survival (%), gross and net yields of prawn were similar in two treatments. In contrast, the GIFT tilapia strain showed a higher (P < 0.05) individual harvesting weight, individual weight gain, specific growth rate ((SGR, % bw d-1), survival, gross and net yields (1935 and 1825 kg ha-1, respectively) combined gross and net yields (2952 and 2784 kg ha-1, respectively), and economic return (3755 US$ with BCR 0.82) than the hybrid Red tilapia