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Ultrasound-mediated method, which can effectively disperse agglomerates or even eliminate agglomeration, has received more and more attentions in industrial crystallization. However, the ultrasound-mediated de-agglomeration mechanism has not been well understood, and no general conclusions have been drawn. In this study, the crystallization and de-agglomeration process of ceftezole sodium agglomerates under ultrasound irradiation were systematically investigated. Kapur function was selected to investigate the de-agglomeration process under different ultrasonic powers. The results revealed that ultrasound could efficiently inhibit agglomeration. Besides, the de-agglomeration of large sized agglomerate particles was found to be easier to occur in comparison with small sized particles due to its higher specific breakage rate. Finally, the de-agglomeration mechanism under ultrasonic irradiation was proposed on the basis of the calculated cumulative breakage functions.Polydopamine (PDA) coating of surfaces is a versatile strategy to fabricate functional films on various substrates, which typically requires oxygen and alkaline pH. Overcoming such limitations may enhance the versatility of this technique. Herein, we develop a simple and green sonochemical process for PDA coatings, which overcomes the limitations of traditional coating technique and expands the versatility of PDA chemistry. The oxidizing radicals generated by high frequency ultrasound (412 kHz) are utilized to initiate and accelerate the polymerization of dopamine. The sonochemical rate of film deposition is found to be about twice faster than that of the traditional method in the presence of oxygen. Importantly, the PDA coatings can be obtained in neutral or acidic aqueous solutions and even in the absence of oxygen. The PDA coatings can be moderated by turning on or off high frequency ultrasound. This study provides an environmentally friendly and economic method for the engineering of PDA coatings independent of the solution pH and nature of dissolved gas.Inter-segmental moments computed by inverse dynamic during gait come from active moments, due to muscle contraction, but also from passive moments, resulting from the resistance of the periarticular structures to their deformation. The evaluation of the proportion of the inter-segmental moments that can be attributed to passive moments has led to divergent results. Thus, the purpose of this study was to systematically search and synthesize the evidence of the contribution of passive moments to inter-segmental moments during healthy and pathological gait. A broad systematic search was performed including four databases. Thirteen studies met all inclusion criteria. Results showed that passive moments participate to inter-segmental moments during gait in a non-negligible way. For the ankle, the evaluation of the proportion of inter-segmental moment attributed to passive structures is 5-20% around the push-off. For the knee, this proportion is 40-98% during late swing and 10-80% during the single support phase. For the hip, it is 20-50% at push-off. For pathological population, it has been shown that this contribution may sometimes be more important, either due to a smaller inter-segmental moment or a larger passive moment. These results suggest that passive mechanisms can contribute substantially to normal human gait, facilitating the propulsion or the braking of the joint. Passive structures, acting as elastic springs, thus help to reduce the energy cost of gait. For pathological gait, studying the contribution of passive moments to inter-segmental moments can help to better understand the aetiology of the pathology.Public procurement is frequently used to contract solid waste collection services. Incomplete contracts and transaction costs increase the need for monitoring and supervision. In such cases, competition by comparison can be a useful tool. www.selleckchem.com/mTOR.html In Barcelona, solid waste collection is regulated by competition, with four delivery zones being contracted out separately. Therefore, it is possible to make relative performance assessments, especially in the areas where the contracted firms operate close to each other. Private firms anticipate stronger competitive pressures near to competitors' zones, even after the contract has been awarded, and they compete on quality. This research studies the influence of the proximity between competitors on the quality of service delivery. Monthly data on the number of complaints regarding waste collection in the city's 73 neighborhoods between 2014 and 2019 is used to evaluate quality. Using count model approaches, our results show that higher quality is provided in neighborhoods closer to other neighborhoods served by a competing firm. Moreover, lower quality is delivered in peripheral neighborhoods, where comparison with competitors' neighborhoods is much harder, if at all possible. The results are consistent with the hypothesis that firms strategically manage quality performance and tend to deliver higher quality where they anticipate that monitoring by the regulator is easier. The findings add to the existing knowledge of competition as a regulatory tool used to obtain more information and providing useful insights to policymakers and regulators to better understand firms' behavior in quality delivery.Given the economic and environmental advantages of using Waste Fried Oil (WFO) as a starting material, this investigation explores the conversion of WFO to Fatty Acid Methyl Ester (FAME) via electrolysis for use in waste. In electrolysis, hydroxyl ions are generated from water in close proximity to the cathode. When hydroxyl ions react with methanol, they produce a species of nucleophilic methoxide which is the main actor in converting WFO into FAME. This study specifically investigates the effects of voltage, catalyst concentration, co solvent amount, rotation speed, and molar ratio of methanol to WFO in electrolytic transesterification converting WFO into FAME using graphite electrodes in the presence of a heterogeneous, catalytic zeolite-chitosan composite. With an alcohol to WFO molar ratio of 81, 1 wt% zeolite-chitosan composite concentration at 40 V in the presence of 2 wt% H2O of the whole solution at room temperature and stirrer rate of 400 rpm and reaction time of 30 min, a 96.5% yield of FAME was achieved.