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This paper discusses a single-blow test procedure for estimating the overall heat and mass transfer coefficients of compact dehumidifier matrices. The procedure consists of three sequential experimental procedures for obtaining, respectively, the core geometry of the test matrix, the active mass of sorbent within the matrix, and the distributions of the temperature and humidity ratio responses with time and distance in the flow direction. The analysis technique paired to the experimental procedure is based upon the transformation of the model partial differential equations into a set of ordinary differential equations. The temperature and mass-fraction distributions are then modeled by a system of nonstiff ordinary differential equations, which can be easily integrated numerically. The Lewis number, defined as the ratio of the overall heat to mass transfer coefficients, determines the shape of the distributions with a dimensionless flow coordinate x+. With a curve fit method, the experimental Lewis number can be determined with acceptable accuracy. The procedure is illustrated with selected experimental results for humid air and a silica gel matrix.

The microbiome from the reproductive tract is being investigated for its putative effect on fertility, embryo development, and health status of the human or animal host postpartum. Besides the presence of a vaginal microbiome, recent studies have claimed the existence and putative role of the uterine microbiome. Yet, the extremely low bacterial numbers and high eukaryotic/prokaryotic DNA ratio make this a highly challenging environment to study with next-generation sequencing (NGS) techniques. Here, we describe the methodological challenges that are typically encountered when performing an accurate analysis of low microbial biomass samples, illustrated by data of our own observational study. In terms of the research question, we compared the microbial composition throughout different parts of the reproductive tract of clinically healthy, mid-lactation Holstein-Friesian cows. Samples were collected from 5 dairy cows immediately after killing. Swabs were taken from the vagina, and from 4 pre-established locations of the uterine endometrium. In addition to the conventional DNA extraction blank controls, sterile swabs rubbed over disinfected disposable gloves and the disinfected surface of the uterus (tunica serosa) before incision were taken as sampling controls. The DNA extraction, DNA quantification, quantitative PCR of the 16S rRNA genes, and 16S rRNA gene sequencing were performed. In terms of NGS data analysis, we performed prevalence-based filtering of putative contaminant operational taxonomic units (OTU) using the decontam R package. Although the bacterial composition differed between the vagina and uterus, no differences in bacterial community structure (α and β diversity) were found among the different locations in the uterus. At phylum level, uterine samples had a greater relative abundance of Proteobacteria, and a lesser relative abundance of Firmicutes than vaginal samples. The number of shared OTU between vagina and uterus was limited, suggesting the existence of bacterial transmission routes other than the transcervical one to the uterus. The mid-lactation bovine genital tract is a low microbial biomass environment, which makes it difficult to distinguish between its constitutive versus contaminant microbiome. The integration of key controls is therefore strictly necessary to decrease the effect of accidentally introduced contaminant sequences and improve the reliability of results in samples with low microbial biomass.

In cooperation with the Belgian gas company we investigated models for the analysis of the Belgian gas consumption. Different static time varying models with temperature as only input have been studied and compared. The main purpose of those models is to do market analysis and more in particular to normalize the gas consumption with respect to temperature.

Abstract The overlapping impact of the Emission Trading System (ETS) and renewable energy (RE) deployment targets creates a classic case of interaction effects. Whereas the price interaction is widely recognized and has been thoroughly discussed, the effect of an overlapping instrument on the abatement attributable to an instrument has gained little attention. This paper estimates the actual reduction in demand for European Union Allowances that has occurred due to RE deployment focusing on the German electricity sector, for the five years 2006 through 2010. Based on a unit commitment model we estimate that CO 2 emissions from the German electricity sector are reduced by 35 to 60 Mtons, or 10% to 18% of what estimated emissions would have been without any RE policy but with the CO 2 price remaining in place at the observed level. Furthermore, we find that the abatement attributable to RE injections is greater in the presence of an allowance price than otherwise. The same holds for the ETS effect in presence of RE injection. This interaction effect is consistently positive for the German electricity system, at least for the considered years, and on the order of 0.5% to 1.5% of emissions.

Dataset for TotalControl flow database precursor simulation of a pressure-driven high Reynolds number boundary layer flow (Casename PDkhi). Further information, including description of the case and dataset can be found in the deliverable report at: Andersen SJ, Meyers J, Munters W, Sood I, Troldborg N. "Flow Database for reference wind farms part 1: precursor simulations"

Liquid phase hydrocarbon oxidation is one of the principal routes towards industrial organic chemicals. However, low product selectivity and associated by-product formation are major problems in several oxidation processes. As a result of the increasingly stringent environmental regulations, the development of oxidation catalysts has been a major challenge in the last decade. An overview of novel selective and clean oxidation catalysts and processes is presented.

Currently, a life cycle assessment is mostly used in a static way to assess the environmental impacts of the energy renovation of buildings. However, various aspects of energy renovation vary in time. This paper reports the development of a framework for a dynamic life cycle assessment and its application to assess the energy renovation of buildings. To investigate whether a dynamic approach leads to different decisions than a static approach, several renovation options of a residential house were compared. To identify the main drivers of the impact and to support decision-making for renovation, a shift of the reference study period—as defined in EN 15643-1 and EN 15978—is proposed (from construction to renovation). Interventions related to the energy renovation are modelled as current events, while interventions and processes that happen afterwards are modelled as future events, including dynamic parameters, considering changes in the operational energy use, changes in the energy mix, and future (cleaner) production processes. For a specific case study building, the dynamic approach resulted in a lower environmental impact than the static approach. However, the dynamic approach did not result in other renovation recommendations, except when a dynamic parameter for electricity production was included.

Abstract Energy communities will play a central role in the sustainable energy transition by helping inform and engage end users to become more responsible consumers of energy. However, the true potential of energy communities can only be unlocked at scale. This scalability requires data-driven solutions that model not just the behavior of building occupants but also of energy flexible resources in buildings, distributed generation and grid conditions in general. This understanding can then be utilized to improve the design and operation of energy communities in a variety of real-world settings. However, in practice, collecting and analyzing the data necessary to realize these objectives forms a large part of such projects, and is often seen as a prohibitive stumbling block. Furthermore, without a proper understanding of the local context, these projects are often at risk of failure due to misplaced expectations. However, this process can be considerably accelerated by utilizing open source datasets and models from related projects, which have been carried out in the past. Likewise, a number of open source, general-purpose tools exist that can help practitioners design and operate LECs in a near-optimal manner. These resources are important because they not only help ground expectations, they also provide LECs and other relevant stakeholders, including utilities and distribution system operators, with much-needed visibility on future energy and cash flows. This review provides a detailed overview of these open-source datasets, models and tools, and the many ways they can be utilized in optimally designing and operating real-world energy communities. It also highlights some of the most important limitations in currently available open source resources, and points to future research directions.

Energy dissipation in the plasma edge is key for future tokamaks. The potential of neon as radiating seeding species in disconnected double null (DDN) configuration is assessed in EAST discharges in high confinement mode (H-mode). As the separation between the two separatrices in the studied DDN discharges is minimum 1.5 cm, the configuration is effectively a single null configuration, and the benefits of the double null topology are minimal. Neon seeding, on the other hand, has a favourable effect: both the target heat flux and the divertor temperature decrease more than five-fold with increased seeding rate in high-recycling conditions. Interpretive edge plasma simulations with SOLPS-ITER in support of ongoing transport analysis are presented. For the unseeded case the numerical results agree with the experimental data within a factor two for the target temperature conditions and measured neutral pressures in the active divertor. The key for achieving good agreement is a suitable selection of coefficients for anomalous transport and neutral conductances between the upper cryopump and the main chamber.