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The outcomes of every batch of anaerobic digesters vary due to differences in equipment, feed composition, and operating conditions. The performance of a bench-scale anaerobic digestion system was investigated in this study with the goal of biomethane production, considering mesophilic requirements at 37°C and thermophilic conditions at 57°C. Three experiments were carried out under mesophilic and thermophilic conditions. A blend of water and solid organic waste was used in the first experiment. The second test involved a mixture of water, material that had undergone prior digestion, and solid organic waste. The third trial incorporated water, previously digested material, solid organic waste, and cow manure as part of the feed. Based on the result, in the third experiment, over 32 days within mesophilic conditions, the average daily biogas and biomethane production per unit of feed mass was quantified as 1610 and 447.10 ml, respectively. Furthermore, the measurements indicated 62.22% and 99.99% increases compared to similar feed subjected to thermophilic conditions. Moreover, the data displayed growth rates of 8.05%, 96.04%, and a substantial rise of 69.47% and 147.7% compared to the outcomes of the second and third experiments performed under mesophilic conditions. Additionally, it can be included that the digestion period of the third test was 60 days shorter than that of the second and one day less than the first trial when operating under mesophilic conditions. As a result, the most effective method for anaerobic digestion involved blending solid organic waste, previously digested material, cow manure, and water under mesophilic conditions. [ABSTRACT FROM AUTHOR]

Photonic topological insulators (PTIs) are electromagnetic structures with highly robust unidirectional edge states, originating from their nontrivial bulk band topology. Here, we propose a plasmonic PTI that supports highly confined one-way edge states capable of transporting deep subwavelength optical frequency plasmons through arbitrary paths without back-scattering. The structure consists of a simple planar array of coupled plasmonic nanoparticles arranged in a perturbed honeycomb lattice that exhibits nontrivial band topology. The operation frequency of the emergent edge states is shown to be independent of the lattice constant, allowing for the miniaturization of the structure. As a high-frequency PTI with a simple and planar design, this structure is compatible with well-established integrated nanofabrication technologies and may find application in planar, compact, and topologically robust integrated nanophotonic devices.

In this study, the effect of ultrasound pretreatment (at 40 kW power, for 20 min) with single partial solvent including water and ethanol and two partial solvents containing water/ethanol in the form of 30% (water): 70% (ethanol) and 60% (water): 40% (ethanol), were considered on the extraction efficiency, total phenolic and flavonoid compounds, as well as the free radical inhibition rate of the St. John’s wort (Hypericum perforatum L.) extract. In order to analyze the data, a completely randomized design was used in three replications, and the comparison of means was done by Duncan's multi-range test, at the probability level of α=1%, and using SPSS 14. Based on the results, the highest amount of extraction efficiency (18.3 %), total phenolic (0.295 mg GAE/g dw) and flavonoid (0.105 mg QE/g dw) compounds and the inhibition rate of free radicals (84.21 %) was measured in the samples pre-treated with ultrasound along with two partial solvents [30% (water): 70% (ethanol)] and the lowest amount of extraction efficiency (4.21%), total phenolic (0.051mg GAE/g dw) and flavonoid (0.0115 mg QE/g dw) compounds as well as free radical inhibition rate (47.53 %) was specified in water (100 %) solvent. [ABSTRACT FROM AUTHOR]

The present study compared the effects of reading input flooding and listening input flooding techniques on the accuracy and complexity of Iranian EFL learners’ speaking skill. Participants were 66 homogeneous intermediate EFL learners who were randomly divided into three groups of 22: Reading input flooding group, listening input flooding group, and control group. The reading flooded input group was exposed to the numerous examples of the target structures through reading. In the same phase, the listening group was given relatively the same task, through listening. The participants’ monologues in the posttest were separately recorded, and later transcribed and coded in terms of accuracy and complexity through Bygate’s (2001) standard coding system. The results of ANCOVA indicated the outperformance of reading input flooding group. The study also supported the trade-off effects (Skehan, 1998, 2009) between accuracy and complexity.