Isopropyl alcohol recovery by heteroazeotropic batch distillation

Solvent recovery is becoming a major issue in the pharmaceutical and specialty chemical industries. Solvent recovery by conventional batch distillation is limited by the frequent presence of azeotropes in the used solvent mixtures. Most distillation processes for the separation of azeotropic or difficult zeotropic mixtures involve the addition of an entrainer (homogeneous and heterogeneous azeotropic distillation or extractive distillation). In this study the recovery of IPA (isopropyl alcohol) from an industrial waste stream (IPA/water mixture) was studied by conventional batch distillation and heteroazeotropic batch distillation, using cyclohexane as entrainer. First the ternary IPA/water/cyclohexane azeotrope (boiling temperature of 64.1 °C), then the binary IPA/cyclohexane azeotrope (boiling temperature of 69.3°C) and finally pure IPA was distilled. 99.96 mass% IPA could be obtained by heteroazeotropic distillation, using cyclohexane as entrainer. By using this procedure the IPA recovery is 97.6%, which is high compared to the conventional distillation techniques. The binary azeotrope could be reused in a subsequent heteroazeotropic batch distillation

Beta-2 adrenergic effects on the sympathetic nervous system

The origin of the studies, described in this thesis, dates back to 1979. In that year my colleague, R.P. Verhoeven, studied the responsiveness of hyperthyroid patients to beta adrenoceptor activation [1]. In his experiments he made the serendipitous observation that the plasma levels of the sympathetic transmitter, noradrenaline, increased during infusion of the beta adrenoceptor agonist isoprenaline. At the time most of us felt that this could be explained by reflex increase in sympathetic nervous activity, due to the vasodilatation caused by isoprenaline, my promotor, Prof. Schalekamp, took a different view. He suggested that the increase in noradrenaline during infusion of isoprenaline could be mediated by presynaptic beta adrenoceptors, which would serve to facilitate the release of noradrenaline [2,3,4]. He gave the impetus to the studies that followed

The genetic basis for individual differences in mRNA splicing and APOBEC1 editing activity in murine macrophages

Alternative splicing and mRNA editing are known to contribute to transcriptome diversity. Although alternative splicing is pervasive and known to contribute to a variety of pathologies, including cancer, the genetic context for individual differences in isoform usage is still evolving. Similarly, although mRNA editing is ubiquitous and associated with important biological processes such as intracellular viral replication and cancer development, individual variations in and the genetic transmissibility of mRNA editing are equivocal. Here, we have used linkage analysis to show that both mRNA editing and alternative splicing are regulated by the macrophage genetic background and environmental cues. We show that distinct loci, potentially harboring variable splice factors, regulate the splicing of multiple transcripts. Additionally, we show that individual genetic variability at the Apobec1 locus results in differential rates of C-to-U editing in murine macrophages; with mouse strains expressing mostly a truncated isoform of Apobec1 exhibiting lower rates of editing. As a proof of concept, we have used linkage analysis to identify 36 high confidence novel edited sites. These results provide a novel and complementary method that can be used to identify C-to-U editing sites in individuals segregating at specific loci and show that, beyond individual DNA sequence and structural changes, differential isoform usage and mRNA editing can contribute to intra-species genomic and phenotypic diversity

An analytical solution to solute transport in continuous arterio-venous hemodiafiltration (CAVHD)

In conventional intermittent hemodialysis, the overall mass transfer coefficient (Ko) of a dialyser is mostly calculated at zero ultrafiltration and at relatively high dialysate flow rates. In continuous arterio-venous hemodiafiltration (CAVHD), the dialysate flow rates are low as comparable to the rates of ultrafiltration flows, making the dialysis treatment as slow as possible. Therefore the overall mass transfer coefficient (Kd) of a CAVHD hemofilter has to be calculated in the presence of ultrafiltration. A mathematical model of CAVHD is presented in order to calculate the diffusive mass transfer coefficient (Kd) for a solute when blood, filtrate and dialysate flow rates and solute concentrations are known. The ultrafiltration volume flux (Jv) is assumed to vary linearly along the axial direction of the hemofilter. The calculated mass transfer coefficient Kd shows that at high values of dialysate flow and low values of ultrafiltration, the overall mass transfer coefficient (Kd) of a CAVHD hemofilter equals mass transfer coefficient (Ko) of a dialyser in conventional intermittent hemodialysis. Also, the calculated mass transfer coefficient Kd shows no significant differences when the ultrafiltration volume flux is assumed to be constant along the length of the hemofilter if no backfiltration occurs in the hemofilter

Table of Contents

Table of contents for Volume 10, Issue 3 of the Linfield Magazin

Design and evaluation of a scalable Internet of Things backend for smart ports

Internet of Things (IoT) technologies, when adequately integrated, cater for logistics optimisation and operations' environmental impact monitoring, both key aspects for today's EU ports management. This article presents Obelisk, a scalable and multi-tenant cloud-based IoT integration platform used in the EU H2020 PortForward project. The landscape of IoT protocols being particularly fragmented, the first role of Obelisk is to provide uniform access to data originating from a myriad of devices and protocols. Interoperability is achieved through adapters that provide flexibility and evolvability in protocol and format mapping. Additionally, due to ports operating in a hub model with various interacting actors, a second role of Obelisk is to secure access to data. This is achieved through encryption and isolation for data transport and processing, respectively, while user access control is ensured through authentication and authorisation standards. Finally, as ports IoTisation will further evolve, a third need for Obelisk is to scale with the data volumes it must ingest and process. Platform scalability is achieved by means of a reactive micro-services based design. Those three essential characteristics are detailed in this article with a specific focus on how to achieve IoT data platform scalability. By means of an air quality monitoring use-case deployed in the city of Antwerp, the scalability of the platform is evaluated. The evaluation shows that the proposed reactive micro-service based design allows for horizontal scaling of the platform as well as for logarithmic time complexity of its service time