16 research outputs found

    Microbubbles enhanced synthetic phorbol ester degradation by ozonolysis

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    A phorbol-12-myristate-13-acetate (TPA) is a synthetic analogue of phorbol ester (PE), a natural toxic compound of Euphorbiaceae plant. The oil extracted from plants of this family is useful source for primarily biofuel. However this oil might also be used as a foodstuff due to its significant nutrition content. The limitations for utilizing the oil as a foodstuff are mainly due to a toxicity of PE. Currently, a majority of PE detoxification processes are expensive as include multi steps alcohol extraction sequence. Ozone is considered as a strong oxidative agent. It reacts with PE by attacking the carbon-carbon double bond of PE. This modification of PE molecular structure yields a non toxic ester with high lipid content. This report presents data on development of simple and cheap PE detoxification process with water application as a buffer and ozone as reactive component. The core of this new technique is an application for a new microscale plasma unit to ozone production and the technology permits ozone injection to the water-TPA mixture in form of microbubbles. The efficacy of a heterogeneous process depends on the diffusion coefficient which can be controlled by contact time and interfacial area. The low velocity of rising microbubbles and high surface to volume ratio allow efficient mass transfer to be achieved during the process. Direct injection of ozone is the most efficient way to process with such highly reactive and short lived chemical. Data on the plasma unit behavior are presented and the influence of gas oscillation technology on the microbubble production mechanism has been discussed. Data on overall process efficacy for TPA degradation is shown

    Effect of Chemical Impurities on Centrifugal Machine Performance: Implications for Compressor Sizing in A CO 2 Transport Pipeline [QUERY]

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    © 2017 The Author(s). Several research studies have been published on CO 2 pipeline transportation. Most of them focus on developing hydraulic models of entire CO 2 pipeline networks. From these studies, a lot of original knowledge has been produced to understand the behaviour of CO 2 pipeline networks under dense phase or supercritical conditions. The globalized modelling approach used in these studies are generally sufficient for carrying out an overall design and operation of an entire CO 2 pipeline network. However, such models are too insufficiently detailed for use in optimizing the performance of a compressor in a CO 2 transport pipeline. This is because in hydraulic models, compression is simulated with adiabatic or polytropic equations which do not account for the geometry and internal fluid flow processes within the compressor. Moreover, in energy requirement calculations involving these equations, compressor efficiency is assumed to be fixed, where as in reality, it varies with change in the purity of the CO 2 stream being compressed. Given that compressors consume most of the energy needed to operate an entire CO 2 pipeline network, it is vital that a detailed analysis of the effect of impurities on machine performance is done as a prerequisite for developing an optimal procedure for compressor sizing and selection. To this end, a quasi-dimensional model based on the laws of conservation was developed and validated for a detailed investigation of the effect of various impurities on the performance of a centrifugal machine handling supercritical carbon dioxide. Results of the study confirm that the power requirement of a compressor is affected by the impurities and provides an insight into the relationship between compressor size, work input and the pressure required to maintain the CO 2 stream flowing in a transport pipeline network in supercritical state

    Efficient compact micro DBD plasma reactor for ozone generation for industrial application in liquid and gas phase systems

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    Ozone is well known as a powerful, fast reacting oxidant. Ozone based processes produce no by-product residual as non-reacted ozone decomposes to molecular oxygen. Therefore an application of ozone is widely accepted as one of the main approaches for a Sustainable and Clean Technologies development. There are number of technologies which require ozone to be delivered to specific points of a production network or reactors construction. Due to space constraints, high reactivity and short life time of ozone the use of ozone generators even of a bench top scale is practically limited. This requires development of mini/micro scale ozone generator which can be directly incorporated into production units. Our report presents a feasibility study of a new micro scale rector for ozone generation (MROG). Data on MROG calibration and indigo decomposition at different operation conditions are presented. At selected operation conditions with residence time of 0.25 s the process of ozone generation is not limited by reaction rate and the amount of ozone produced is a function of power applied. It was shown that the MROG is capable to produce ozone at voltage level starting from 3.5kV with ozone concentration of 5.28*10⁻⁶ (mol/L) at 5kV. This is in line with data presented on numerical investigation for a MROG. It was shown that in compare to a conventional ozone generator, MROG has lower power consumption at low voltages and atmospheric pressure. The MROG construction makes it applicable for both submerged and dry systems. With a robust compact design MROG can be used as an integrated module for production lines of high complexity

    Small volume laboratory on a chip measurements incorporating the quartz crystal microbalance to measure the viscosity-density product of room temperature ionic liquids

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    A microfluidic glass chip system incorporating a quartz crystal microbalance (QCM) to measure the square root of the viscosity-density product of room temperature ionic liquids (RTILs) is presented. The QCM covers a central recess on a glass chip, with a seal formed by tightly clamping from above outside the sensing region. The change in resonant frequency of the QCM allows for the determination of the square root viscosity-density product of RTILs to a limit of ∼ 10 kg m−2 s−0.5. This method has reduced the sample size needed for characterization from 1.5 ml to only 30 μl and allows the measurement to be made in an enclosed system

    Maintenance of head and neck tumor on-chip: gateway to personalized treatment?

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    Aim: Head and neck squamous cell carcinomas (HNSCC) are solid tumors with low overall survival (40–60%). In a move toward personalized medicine, maintenance of tumor biopsies in microfluidic tissue culture devices is being developed. Methodology/ results: HNSCC (n = 15) was dissected (5–10 mg) and either analyzed immediately or cultured in a microfluidic device (37°C) for 48 h. No difference was observed in morphology between pre- and postculture specimens. Dissociated samples were analyzed using trypan blue exclusion (viability), propidium iodide flow cytometry (death) and MTS assay (proliferation) with no significant difference observed highlighting tissue maintenance. Computational fluid dynamics showed laminar flow within the system. Conclusion: The microfluidic culture system successfully maintained HNSCC for 48 h, the culture system will allow testing of different treatment modalities with response monitoring. Lay abstract: Head and neck cancers often have a poor treatment outcome. In order to study the response of the tissue, a miniaturized culture system has been developed to keep a small piece of tumor alive. In the current study, we show that small pieces of cancer tissue can be maintained in the system, using tissue structure and viability of single cells as a guide. In future work, patient equivalent treatments can be applied to these microculture systems to investigate individual patient tumor responses, which could help to guide treatment selection

    Long-term imaging of calcium dynamics using genetically encoded calcium indicators and automatic tracking of cultured cells

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    © 2018 Future Science. All rights reserved. Calcium dynamics is crucial for many signaling pathways and cell functions. Understanding how calcium regulates cell function often requires long-term imaging of calcium dynamics. Here we report a methodological approach of long-term (5–10 h) imaging of calcium dynamics in cultured cells. The approach links calcium imaging using genetically encoded calcium indicators and semi-automatic tracking of individual cells. It can be used in a large variety of situations, ranging from the role of calcium in biological processes to cell heterogeneity and screening of drugs modifying signaling pathways

    Formulation and Physical Properties of Citronella Oil Emulsion on Differences in Emulsifiers With The Addition of Maltodextrin

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    Various studies have shown that citronella oil is a fatty oil that is efficacious for reducing microbial activity in food. Emulsions are preparations containing two immiscible substances, usually water and oil, where the liquid which when dispersed becomes small particles in another liquid. The combination of maltodextrin and citronella oil requires an emulsifying agent. Methyl cellulose and gum arabic have been widely used with maltodextrin because they can increase the stability of the emulsion formed. Apart from being an emulsifier, the addition of methyl cellulose and gum arabic aims to strengthen the resulting coating layer. This study using response surface methodology (RSM) for the formulation of thin layer emulsion-based edible coating materials, studies the characteristics and stability of the thin layer emulsion system on edible coating materials, and studies the effect of storage temperature on the stability of the thin layer emulsion system on edible coating materials by observing the physical properties of the emulsion which includes the type emulsion, droplet size, and creaming index on sedimentation volume for 1 month of storage on variations of emulsifier methyl cellulose and Arabic gum and addition of maltodextrin. The results of observations based on tests on the type of emulsion, droplet size, and creaming index on the sedimentation volume for 1 month of storage on variations in emulsifier methyl cellulose and Arabic gum and the addition of maltodextrin showed that there was a significant difference

    The Use of Tissue-on-Chip Technology to Focus the Search for Extracellular Vesicle miRNA Biomarkers in Thyroid Disease

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    Citation: Haigh, T.; Beattie, H.; Wade, M.A.; England, J.; Kuvshinov, D.; Karsai, L.; Greenman, J.; Green, V. The Use of Tissue-on-Chip Technology to Focus the Search for Extracellular Vesicle miRNA Biomarkers in Thyroid Disease. Int. J. Mol. Sci. 2024, 25, 71. Abstract: Small extracellular vesicles (sEVs) contain microRNAs (miRNAs
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