From the article: "A facile approach for the fabrication of large-scale interdigitated nanogap electrodes (nanogap IDEs) with a controllable gap was demonstrated with conventional micro-fabrication technology to develop chemocapacitors for gas sensing applications. In this work, interdigitated nanogap electrodes (nanogap IDEs) with gaps from 50–250 nm have been designed and processed at full wafer-scale. These nanogap IDEs were then coated with poly(4-vinyl phenol) as a sensitive layer to form gas sensors for acetone detection at low concentrations. These acetone sensors showed excellent sensing performance with a dynamic range from 1000 ppm to 10 ppm of acetone at room temperature and the observed results are compared with conventional interdigitated microelectrodes according to our previous work. Sensitivity and reproducibility of devices are discussed in detail. Our approach of fabrication of nanogap IDEs together with a simple coating method to apply the sensing layer opens up possibilities to create various nanogap devices in a cost-effective manner for gas sensing applications"
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Sensor platforms can benefit from the incorporation of polymerbrushes since brushes can concentrate the analyte near the sensor surface. Brushesthat absorb acetone vapor are of particular interest since acetone is an importantmarker for biological processes. We present a simple procedure to synthesize acetoneresponsivepoly(methyl acrylate) brushes. Using spectroscopic ellipsometry, we showthat these brushes respond within seconds and swell by more than 30% when exposedto acetone vapor. Moreover, quartz crystal microbalance measurements demonstrate that the brushes can be exploited to increasethe acetone detection sensitivity of sensors by more than a factor 6. Surprisingly, we find that the swelling ratio of the brushes inacetone vapor is independent of the grafting density and the degree of polymerization of the polymers in the brush. This isqualitatively different from swelling of the same brushes in liquid environments, where the swelling ratio decreases for increasinggrafting densities. Yet, it indicates that the brushes are robust and reproducible candidates for implementation in vapor sensorsystems.
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Natural Deep Eutectic Solvents (NADES) represent a green chemistry alternative to utilization of common hazardous organic solvents. They were introduced by Abbott et al. [1], and were found to have a wide range of compositions and favorable properties. NADES are typically obtained by mixing hydrogen-bond acceptors (HBA), with hydrogen bond donors (HBD), leading to a significant depression of the melting point. The availability of components, simple preparation, biodegradability, safety, re usability and low cost are the significant advantages that call for research on their analytical applications. Three methods are most commonly used for preparing NADES: a) heating and stirring: the mixture until a clear liquid is formed; b) evaporating solvent from components solution with a rotatory evaporator; c) freeze drying of aqueous solutions.The common solvents for the extraction of anthocyanins are acidified mixtures of water with ethanol, methanol, or acetone. The anthocyanins extracts are susceptible to degradation due to high temperature, and the solvent properties (e.g. high pH) and the whole process can often be time-consuming. Extraction of anthocyanins from red cabbage by four NADES was investigated. It was demonstrated that NADES have comparable extraction efficiencies with conventional method with 0.1 M water solution of HCl. This indicates a possibility of utilization the Green chemistry extraction processes as a promising new green-extraction technology with low cost efficiency and environment friendly technology for production of safe food additives.
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Polycyclic aromatic hydrocarbons (PAHs) are a group of more than hundred compounds that are ubiquitous in our environment. Some of these PAHs are known to be carcinogenic, mutagenic and teratogenic. PAHs have been detected in dried herbs that were cultured in The Netherlands as well as in other European countries above the maximum levels in dried herbs set by the EU (EU, 2015) for benzo(a)pyrene and the sum of the following four PAHs benzo(a)pyrene, benzo[a]anthracene, benzo[b]fluoranteen and chrysene. The origin of these PAHs in herbs is unknown. VNK cultivates, harvests and dries herbs including valerian and would like to identify the source of PAHs to comply to the EU limits for PAHs in herbs. The goal of the present study was to identify the source of PAHs found in valerian root, and to identify possible measures to reduce the concentration of PAHs in valerian root.
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In a long-term project, together with Courage, we are investigating whether it is possible to determine volatile fatty acids, methane or acetone in the air blown from dairy cows. These substances are associated with health and digestion of the cow. We are working on a sensor together with tech partners and we compare measured values in breathing air with both activity measurements with the Nedap sensors and with manual health scores. In een langlopend project bekijken we samen met Courage of het mogelijk is om in uitgeblazen lucht van melkkoeien vluchtige vetzuren, methaan of aceton te bepalen. Deze stoffen zijn geassocieerd met gezondheid en vertering van de koe. Samen met tech-partners werken we aan een sensor en we vergelijken gemeten waardes in ademlucht met zowel activiteitsmetingen met de Nedap sensoren als met handmatige gezondheidsscores.
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Summary Project objectives This study fits into a larger research project on logistics collaboration and outsourcing decisions. The final objective of this larger project is to analyze the logistics collaboration decision in more detail to identify thresholds in these decisions. To reach the overall objectives, the first step is to get a clearer picture on the chemical and logistics service providers industry, sectors of our study, and on logistics collaboration in these sectors. The results of this first phase are presented in this report. Project Approach The study consists of two parts: literature review and five case studies within the chemical industry. The literature covers three topics: logistics collaboration, logistics outsourcing and purchasing of logistics services. The five case studies are used to refine the theoretical findings of the literature review. Conclusions Main observations during the case studies can be summarized as follows: Most analyzed collaborative relationships between shippers and logistics service providers in the chemical industry are still focused on operational execution of logistics activities with a short term horizon. Supply management design and control are often retained by the shippers. Despite the time and cost intensive character of a logistics service buying process, shippers tendering on a very regular basis. The decision to start a new tender project should more often be based on an integral approach that includes all tender related costs. A lower frequency of tendering could create more stability in supply chains. Beside, it will give both, shippers and LSPs, the possibility to improve the quality of the remaining projects. Price is still a dominating decision criterion in selecting a LSP. This is not an issue as long as the comparison of costs is based on an integral approach, and when shippers balance the cost criterion within their total set of criteria for sourcing logistics services. At the shippers' side there is an increased awareness of the need of more solid collaboration with logistics service providers. Nevertheless, in many cases this increased awareness does not actually result in the required actions to establish more intensive collaboration. Over the last years the logistics service providers industry was characterized by low profit margins, strong fragmentation and price competition. Nowadays, the market for LSPs is changing, because of an increasing demand for logistics services. To benefit from this situation a more pro-active role of the service providers is required in building stronger relationships with their customers. They should pay more attention on mid and long term possibilities in a collaborative relation, in stead of only be focused on running the daily operation.
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Immunofluorescence microscopy in this study shows that GLUT-4 protein expression is fibre-type specific within a muscle. It is postulated that both fibre-type-dependent and fibre-type-independent factors affect GLUT-4 expression.
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This article gives information on an international ring trial of the epidermal-equivalent (EE) sensitizer potency assay.
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Muscle fiber-type specific expression of UCP3-protein is reported here for the firts time, using immunofluorescence microscopy
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