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Among various bioreactors examined in anaerobic digestion and dark fermentation, UASB bioreactor has shown to be a promising alternative. However, mass transfer resistance and biomass washout have been the issues that reported as draw backs of the granular system in the literature. Another problem associated with such a system is its long start-up period as a result of biomass washout and long microbial granulation stage. In this paper, the results obtained from an UASFF bioreactor in methane (AD process) and hydrogen (DF process) production from POME, are presented to assess mass transfer of substrate into the granules and also study the role of internal packing used in the middle part of reactor in the process stability. The value of effectiveness factor, η, for AD and DF processes were calculated to be 0.96 and 0.94, respectively, indicating that there was no mass transfer resistance due to internal and/or external factors. The results showed that the packing material could retain biomass in the reactor and had outstanding contribution in the granulation enhancement. Its role as a supplementing treatment stage was more significant at low HRTs and up-flow velocities.

The paper comprises a systematic experimental investigation into the influence of AC test source parameters on the leakage current pulses, voltage fluctuations and flashover voltages of polluted insulators. The test techniques include both salt-and clean-fog methods, while the test insulators comprise long-rod and cap and pin strings of different lengths as well as support columns.

A detailed analysis of the effects of ground grid configuration on grounding performance has been carried out for uniform and horizontally stratified soils with multiple layers. The results of the analysis reveal that the most efficient and cost-effective design is highly dependent on soil structure type and characteristics. In the absence of ground rods, grounding grids with uniform mesh size are quite efficient in soils having a thin (relative to grid size) high resistivity (relative to the lower layers) top soil, while grids with small mesh size at the periphery of the grid provide optimum performance in uniform soils and soils with low resistivity top soils. Ground rods were found to be effective only when a significant portion of their length is in contact with a low resistivity soil, as expected.

Experiments were carried out to determine the accuracy and validity of estimations of hepatic blood flow from systemic clearances of ethanol during very low dose (8 μmol∙min−1∙kg−1) infusions of ethanol in anesthetized cats. Systemic clearances were compared with directly measured hepatic blood flow using a hepatic venous long-circuit technique. This technique allowed direct measurement and alteration of hepatic blood flow and collection of arterial, portal, and hepatic venous blood samples without depletion of the animal's blood volume. In 18 cats, Vmax for ethanol was 93 ± 7 μmol∙min−1 per 100 g liver or 21 ± 2 μmol∙min−1∙kg·body weight−1 and Km was 144 ± 19 μM in terms of logarithmic mean sinusoidal concentration. At the dose of 8 μmol∙min−1∙kg body weight−1 used for estimation of hepatic blood flow, extraction was 0.95 ± 0.07 (mean ± SD). Systemic clearance of ethanol overestimated directly measured hepatic blood flow by 15 ± 16%. Hepatic blood flow changes expressed as percentages of the control level were accurately estimated from systemic ethanol clearance (100 ± 10%). Since 73 ± 12% of the infused ethanol was eliminated by the liver and 83 ± 11% was eliminated by the splanchnic bed, an extrasplanchnic uptake of 17% accounted for the overestimation of hepatic blood flow. Estimation of hepatic blood flow from systemic clearances of ethanol during very low dose infusions may have advantages over other clearance methods. Its use in cats was illustrated in a separate series of experiments and it was shown that surgery significantly reduced hepatic blood flow. The method may merit trial for estimation of hepatic blood flow in humans.

Abstract Synchronous cultures of the fission yeast Schizosaccharomyces pombe 972 h −1 are most sensitive to killing by 15 min, 49 °C pulses during a stage stretching from nuclear division through short G1 and S phases to a point early in G2. In this work the cell cycle position of the S phase has been altered by growing the cells in the presence of 2-phenylethanol. The heat sensitivity of these cells was greater at all stages of the cell cycle compared with the cells grown without 2-phenylethanol. However, the position of the most heat sensitive stage in the cell cycle was unaltered. This heat sensitive stage did not include S phase in the cells grown with 2-phenylethanol.

A mathematical model of the LiAl/LiCl, KCl/FeS cell has been used to study the behavior of the system during relaxation and charging. The effects of state of charge, cell temperature, and current density are presented, and the influence of a period of relaxation on the subsequent charging operation is investigated. In addition, factors that can have a significant impact on the charging characteristics are identified.

Short-term generation scheduling is an important function in daily operational planning of power systems. It is defined as optimal scheduling of power generators over a scheduling period while respecting various generator constraints and system constraints. Objective of the problem includes costs associated with energy production, start-up cost and shut-down cost along with profits. The resulting problem is a large scale nonlinear mixed-integer optimization problem for which there is no exact solution technique available. The solution to the problem can be obtained only by complete enumeration, often at the cost of a prohibitively computation time requirement for realistic power systems. This paper presents a hybrid algorithm which combines Lagrangian Relaxation (LR) together with Evolutionary Algorithm (EA) to solve the problem in cooperative and competitive energy environments. Simulation studies were carried out on different systems containing various numbers of units. The outcomes from different algorithms are compared with that from the proposed hybrid algorithm and the advantages of the proposed algorithm are briefly discussed.

Purpose This study aims to consider environmental sustainability, a global challenge under the preview of sustainable development goals, highlighting the significance of knowledge economy in attaining sustainable aggregate demand behavior globally. For this purpose, 155 countries that have data available from 1995 to 2021 were selected. The purpose of selecting these countries is to test the global responsibility of the knowledge economy to attain environmental sustainability. Design/methodology/approach Results are estimated with the help of panel quantile regression. The empirical existence of aggregate demand-based environmental Kuznets curve (EKC) was tested using non-linear tests. Moreover, principal component analysis has been incorporated to construct the knowledge economy index. Findings U-shaped aggregate demand-based EKC at global level is validated. However, environmental deterioration increases with an additional escalation after US$497.945m in aggregate demand. As a determinant, the knowledge economy is reducing CO2 emissions. The knowledge economy has played a significant role in global responsibility, shifting the EKC downward and extending the CO2 reduction phase for every selected country. Further, urbanization, energy intensity, financial development and trade openness significantly deteriorate the environmental quality. Originality/value This study contains the empirical existence of aggregate demand-based EKC. The role of the knowledge economy is examined through an index which is calculated by using four pillars of the knowledge economy (technology, innovations, education and institutions). This study is based on a combined panel of all the countries for which the data was available.