57 research outputs found

    Green supported liquid membranes: The permeability activity-based linear operation (PABLO) method

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    Supported liquid membranes (SLMs) containing novel green solvents are proposed as a sustainable alternative separation process in the recovery of biomolecules. In this work, succinic acid has been successfully extracted from model fermentation broths through a stripping phase-facilitated transport mechanism with four different green supported liquid membranes: two eutectic solvents (DL-menthol:OctA and N4444Cl:OctA), the bio-based solvent eucalyptol and the ionic liquid C4pyrr]Tf2N]. A permeability activity-based model that takes into account for the first time solute-phase affinities has been developed using the quantum chemical COSMO-RS method; the model corrects the mass transfer driving force and allows extraction predictions beyond the concentration equilibrium. The best recovery has been achieved experimentally for the eucalyptol-based SLM (concentration factor of 1.4) using an alkaline aqueous solution (0.5 M NaOH) as the stripping phase. A countercurrent cascade extraction process design is proposed, and a graphical method to determine the stage number, interstage concentrations as well as mass transfer area requirements is presented. This new tool, the Permeability Activity-Based Linear Operation (PABLO) method, will substantially enhance the process design of SLMs technology for the biorefinery industry

    Towards the technological maturity of membrane distillation: the MD module performance curve

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    Membrane distillation (MD) is constantly acknowledged in the research literature as a promising technology for the future of desalination, with an increasing number of studies reported year after year. However, real MD applications still lag behind with only a few pilot-plant tests worldwide. The lack of technology transfer from academia to industry is caused by important gaps between its fundamental basis and the process design. Herein, we explore critical disconnections by conducting coupled mass and heat transfer modeling and MD simulations; we use well-known MD mass and heat transfer equations to model and simulate flux over a typical MD membrane for different geometries, areas, and operational conditions in direct contact configuration. From the analysis of the results, we propose research guidelines and process development strategies, and construct an MD module performance curve. From this graph, permeate flow rate, thermal energy consumption and outlet temperatures can be determined for given feed inlet conditions (temperature and concentration). Comprehensive tools such as this MD module curve and good communication between membrane developers and process engineers are required to accelerate the process of bringing the MD technology from a still-emerging status to a maturity level

    Immobilized graphene oxide-based membranes for improved pore wetting resistance in membrane distillation

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    Membrane distillation (MD) is a useful method for the purification of difficult feedwaters but it cannot be applied in a range of industries due to pore wetting. In this work, graphene oxide (GO) laminate coatings are explored to overcome the pore wetting issues. Air gap MD (AGMD) configuration was considered, using a 35 g L-1 NaCl solution with 150 mg L-1 (150 ppm) of Triton X-100 surfactant as feed material. The GO is deposited as a laminate membrane on top of a commercial porous polyvinylidene fluoride (PVDF) support and good adhesion is achieved through the use of polydopamine (PDA) to form a hydrophilic tri-layer membrane. The small pore size achieved with the laminate GO led to increased pore wetting resistance for at least 90 h compared to 20 min with pristine commercial PVDF. Additionally, the extra layers of GO and PDA did not affect the membrane flux. Overall, a tri-layer immobilized GO membrane is synthesized with superior performance when compared to current commercial membranes, meaning that MD can be used for a new range of wastewater applications

    PIM-1 membranes containing POSS - graphene oxide for CO2 separation

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    PIM-1 mixed matrix membranes (MMMs) were fabricated with polyhedral oligomeric silsesquioxane (POSS) and graphene oxide (GO) functionalized with POSS (GO-POSS), and tested for CO2/N2 (single gas) and CO2/CH4 (1:1, v:v gas mixture). The CO2 permeability of the best performing fresh MMM (containing 0.05 wt% GO-POSS) was ~ 12000 Barrer, which is 69% higher than that of the neat PIM-1 membrane, with about the same selectivity (CO2/CH4 selectivity ~ 12 and CO2/N2 selectivity ~ 20). In both cases, the gas separation data surpass the 2008 Robeson upper bound. In addition to the initial CO2 permeability enhancement, the use of GO-POSS is an efficient strategy to slow down physical aging. The MMM at a filler loading of 0.75 wt% showed less than half of the reduction in CO2 permeability than the neat PIM-1 membrane 160 days after preparation (26% for the MMM vs 58% for the purely polymeric one). © 2022 The Author(s

    Thin film nanocomposite membranes of PIM-1 and graphene oxide/ZIF-8 nanohybrids for organophilic pervaporation

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    In this work, thin film nanocomposite (TFN) membranes of super-glassy polymer PIM-1 containing zeolitic imidazolate framework-8 (ZIF-8)/graphene oxide (GO) composites (ZG) have been prepared by dip-coating onto water pre-impregnated polyvinylidene fluoride (PVDF) substrates. Higher flux and improved separation factors as compared to bare PIM-1 thin film composite (TFC) membranes have been achieved in organophilic pervaporation; for an aqueous feed solution with 5 wt% of butanol at 65 °C, a total permeate flux of 7.9 ± 0.69 kg m-2h-1 and a separation factor (ßBtOH/H2O) of 29.9 ± 1.99 have been obtained with a TFC membrane containing 0.5 wt% of ZG filler. The pervaporation separation index (PSI) of this membrane (228 kg m-2h-1) is amongst the highest values reported in the literature. This excellent performance is attributed to the formation of a defect-free PIM-1 active layer (<1 µm) and the hydrophobic nature of the ZG fillers. © 2022 The Author

    Optique: Zooming in on Big Data

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    Despite the dramatic growth of data accumulated by enterprises, obtaining value out of it is extremely challenging. In particular, the data access bottleneck prevents domain experts from getting the right piece of data within a constrained time frame. The Optique Platform unlocks the access to Big Data by providing end users support for directly formulating their information needs through an intuitive visual query interface. The submitted query is then transformed into highly optimized queries over the data sources, which may include streaming data, and exploiting massive parallelism in the backend whenever possible. The Optique Platform thus responds to one major challenge posed by Big Data in data-intensive industrial settings

    Alcohol intake and risk of breast cancer: the euramic study

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    To evaluate the association of alcohol intake with the risk of breast cancer in post-menopausal women, we analyzed the data from an international case-control study conducted in five European countries (FRG, Switzerland, Northern Ireland, the Netherlands and Spain). Information on alcohol intake was available in 315 cases and 364 controls. Medians for the tertiles of alcohol intake among current drinkers were 1.7, 6.0, and 20.0 g/day. Adjusted relative risks (and 95% confidence intervals) of breast cancer for each tertile of intake in current drinkers, compared to never drinkers, were 1.00 (0.60-1.67), 1.01 (0.60-1.73), and 1.18 (0.69-2.03). The adjusted relative risk for ex-drinkers was 1.73 (1.07-2.79). Among both current drinkers and ex-drinkers, the relative risk was higher for those with body mass index above the median compared to those with body mass index below the median. These results do not support a dose-response effect of alcohol on breast cancer risk, although consumption levels were too low to exclude increased risk with high regular intake. Further research is necessary to evaluate the risk of developing breast cancer among ex-drinkers and the potential interaction between body mass index and alcohol drinking.Thc EURAMIC Study was supported as an European Community Concerted Action by the Commission of the European Communities (con-tracts number MR4*/265/NL and MR4*/CT91/0369[SSMA]). The natio-nal studies were financed by grants from the Dutch Ministry of Health, the Spanish "Fondo de Invcstigacioncs Sanitarias" (91E0575), the German Fe-deral Health Office, the Cancer Research Switzerland (AKT76), the Swiss National Science Foundation (32-9257-87), the Yrjö Jahnsson Foundation, the Ulster Cancer Foundation and Milk Intervention Board (co-responsibi-lity Levy Disbursement Reg EEC 110/90 Contract 77.2).S

    Mimicry and well known genetic friends: molecular diagnosis in an Iranian cohort of suspected Bartter syndrome and proposition of an algorithm for clinical differential diagnosis.

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    BACKGROUND: Bartter Syndrome is a rare, genetically heterogeneous, mainly autosomal recessively inherited condition characterized by hypochloremic hypokalemic metabolic alkalosis. Mutations in several genes encoding for ion channels localizing to the renal tubules including SLC12A1, KCNJ1, BSND, CLCNKA, CLCNKB, MAGED2 and CASR have been identified as underlying molecular cause. No genetically defined cases have been described in the Iranian population to date. Like for other rare genetic disorders, implementation of Next Generation Sequencing (NGS) technologies has greatly facilitated genetic diagnostics and counseling over the last years. In this study, we describe the clinical, biochemical and genetic characteristics of patients from 15 Iranian families with a clinical diagnosis of Bartter Syndrome. RESULTS: Age range of patients included in this study was 3 months to 6 years and all patients showed hypokalemic metabolic alkalosis. 3 patients additionally displayed hypercalciuria, with evidence of nephrocalcinosis in one case. Screening by Whole Exome Sequencing (WES) and long range PCR revealed that 12/17 patients (70%) had a deletion of the entire CLCNKB gene that was previously identified as the most common cause of Bartter Syndrome in other populations. 4/17 individuals (approximately 25% of cases) were found to suffer in fact from pseudo-Bartter syndrome resulting from congenital chloride diarrhea due to a novel homozygous mutation in the SLC26A3 gene, Pendred syndrome due to a known homozygous mutation in SLC26A4, Cystic Fibrosis (CF) due to a novel mutation in CFTR and apparent mineralocorticoid excess syndrome due to a novel homozygous loss of function mutation in HSD11B2 gene. 1 case (5%) remained unsolved. CONCLUSIONS: Our findings demonstrate deletion of CLCNKB is the most common cause of Bartter syndrome in Iranian patients and we show that age of onset of clinical symptoms as well as clinical features amongst those patients are variable. Further, using WES we were able to prove that nearly 1/4 patients in fact suffered from Pseudo-Bartter Syndrome, reversing the initial clinical diagnosis with important impact on the subsequent treatment and clinical follow up pathway. Finally, we propose an algorithm for clinical differential diagnosis of Bartter Syndrome

    Polymer nanofilms with enhanced microporosity by interfacial polymerization

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    Highly permeable and selective membranes are desirable for energy-efficient gas and liquid separations. Microporous organic polymers have attracted significant attention in this respect owing to their high porosity, permeability, and molecular selectivity. However, it remains challenging to fabricate selective polymer membranes with controlled microporosity which are stable in solvents. Here we report a new approach to designing crosslinked, rigid polymer nanofilms with enhanced microporosity by manipulating the molecular structure. Ultra-thin polyarylate nanofilms with thickness down to 20 nm were formed in-situ by interfacial polymerisation. Enhanced microporosity and higher interconnectivity of intermolecular network voids, as rationalised by molecular simulations, are achieved by utilising contorted monomers for the interfacial polymerisation. Composite membranes comprising polyarylate nanofilms with enhanced microporosity fabricated in-situ on crosslinked polyimide ultrafiltration membranes show outstanding separation performance in organic solvents, with up to two orders of magnitude higher solvent permeance than membranes fabricated with nanofilms made from noncontorted planar monomers

    How do high glycemic load diets influence coronary heart disease?

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