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This study assessed the hand hygiene performance in French nursing homes using the consumption of alcohol-based hand rubs (AHRs) as a surrogate. Nursing homes from the 17 French regions were contacted to collect their AHR consumption and occupancy in 2018 and 2019. A total of 1290 nursing homes from 15 French regions participated in the survey. The estimated median number of hand hygiene actions per resident-day was 1.48 (interquartile range: 1.04-2.03) in 2018 and 1.60 (1.10-2.26) in 2019. A significantly higher AHR consumption was observed in public nursing homes with an infection control team or link nurse.

Abstract This paper addresses the problem of how to synthesize mass and heat exchange processes, in which stream flowrates and their inlet compositions and temperatures may vary according to a set of discrete values. A unified hyperstructure representation of mass and heat exchange alternatives is introduced to account for all mass and heat integration possibilities. A multiperiod mixed integer nonlinear programming (MINLP) model is then developed, where a total annualized cost is minimized by balancing capital investment cost (of the heat and mass exchange equipment and their interconnections) to operating cost (of the hot-cold utilities, mass separating agents, etc.). As illustrated with the example problems, the proposed model can be effectively employed for the synthesis of flexible heat exchanger networks (HENs) and mass exchanger networks (MENs) separately or, for the synthesis of separation processes involving both heat and mass transfer.

This paper presents inviscid compressible simulations for the impulsive blocking of a vortex, with non-zero axial velocity along its core, by a flat plate orthogonal to the vortex axis. This is a simplified model of the blade–vortex interaction between the tail rotor of a helicopter and the trailing vortex system formed by the main rotor system. There are two important elements to this phenomenon. One is the vortex response, including a physical description for the evolution of complex vortical structures near the plate surface, and the second is the resultant pressure wave structure and the manner of its propagation away from the plate surface. This paper focusses more on the vortex structure, and how this is affected by compressibility and the initial transient shock structures that form at the plate surface.

AbstractBuddleja davidii is a unique biomass that has many attractive agroenergy features, especially its wide range of growth habitat. The anatomical characteristics of B. davidii were investigated before and after ethanol organosolv pretreatment (one of the leading pretreatment technologies) in order to further understand the alterations that occur to the cellular structure of the biomass which can then be correlated with its enzymatic digestibility. Results showed that the ethanol organosolv pretreatment of B. davidii selectively removes lignin from the middle lamella (ML), which does not significantly disrupt the crystalline structure of cellulose. The removal of ML lignin is a major factor in enhancing enzymatic cellulose‐to‐glucose hydrolysis. The pretreatment also causes cell deformation, resulting in cracks and breaks in the cell wall. These observations, together with characterization analysis of the cell wall polymer material, lend support to the hypothesis that the physical distribution of lignin in the biomass matrix is an important structural feature affecting biomass enzymatic digestibility. Biotechnol. Bioeng. 2010;107: 795–801. © 2010 Wiley Periodicals, Inc.

Abstract In this study, the process of carbon dioxide (CO2) desorption from two saturated solutions of monoethanolamine (MEA) and diethanolamine (DEA) was performed in a microchannel made of stainless-steel grade 316 with a circular cross-section (diameter: 800 μm, length: 35 cm). The operating variables in this study were temperature (55, 75 and 95 °C), rich solvent flow rate (0.3, 0.9 and 1.5 ml/min), and inlet solvent concentration (10, 20 and 30 wt% of the amine). The mass transfer efficiency was determined based on the desorption percentage, volumetric liquid-side mass transfer coefficient (kLaV), volumetric overall mass transfer flux (NCO2aV), and energy consumption per unit mass CO2 (R). The results showed that the use of a microchannel significantly increased the mass transfer rate and decreased energy consumption per removed CO2. The results also showed that the amount of kLaV for the two solvents of MEA and DEA was 1.91 and 3.48 1/s, respectively. Moreover, the R-value for the two solvents of MEA and DEA was 1.3 and 1.63 MJ/kg CO2, respectively, which is at least three times lower than that of other mass transfer devices.

Abstract New energy vehicles have significant prospects in reducing greenhouse gas emission and environmental pollution. Lithium-ion batteries are the favored power source in electric vehicles because of their high energy density and long service life. The battery performance depends noticeably on the temperature. Battery thermal management system, which can keep the battery pack working in a proper temperature range, not only affects significantly the battery pack system performance but is also vital for the safety and stability. This article mainly summarizes the thermal management models in the literature which can predict heat generation, heat transfer and the temperature distribution within the battery cell, module and pack. The multi-physical battery thermal management systems are divided into three categories based on different methods of cooling the phase change materials such as air-cooled system, liquid-cooled system, and heat-pipe-cooled system. The emergency battery thermal battier methods are also summarized in multi-scale included material scale, battery management system and supplementary system. Finally, we propose a novel digital solution for full-lifespan thermal management control of EV power system based on CHAIN framework that helps improve the power battery temperature control strategy applying multiple working conditions.

Much of the debate on sustainability is predicated on the belief that environmental demands lead to the production of sustainable technologies that induce environmental benefits. This fails to account for the influential ways technologies are used in practice, and the interactions between users and technologies that shape their environmental effects. This article uses the example of how cars and their drivers together accomplish the practice of driving through their interactions with each other, and explores the implications this has for generating environmental outcomes. We draw on a body of literature that argues how together, users and technologies participate in carrying out practices that actively shape outcomes, and we show how and why this applies to sustainability. The article presents the case of the Toyota Prius, analyzing Toyota’s intent in designing a sustainable car and contrasting it with the perspectives of thirty-eight of its drivers. We find that the possibility for fuel and carbon reduction is coproduced and is a result of complex interactions between technology, drivers, and driving practice.

We compare two models to determine the size of grid units and dispatch in a wind-diesel power system with hydrogen storage. Both take as data 1-year time series of hourly wind speed and electricity demand, and their objective is to minimise cost. Our first model, based on linear programming, generates as output a combination of capacities and a year time series for the dispatch variables. Our second model runs a fixed dispatch rule over several capacity combinations and selects the cheapest option. The dispatch rule can then be improved through comparison with the linear programming solution. At present costs, the hydrogen storage-conversion system is excluded from the solutions, so the interesting operation rules associated with the option of harvesting do not arise. However, the costs of hydrogen storage technologies are decreasing with investment. By running our model with prospective costs for year 2010, we see storage emerge in the optimum, and thus a sample of the operation patterns that will occur in a renewable dominated grid.