Review on Blueprint of Designing Anti-Wetting Polymeric Membrane Surfaces for Enhanced Membrane Distillation Performance

Recently, membrane distillation (MD) has emerged as a versatile technology for treating saline water and industrial wastewater. However, the long-term use of MD wets the polymeric membrane and prevents the membrane from working as a semi-permeable barrier. Currently, the concept of antiwetting interfaces has been utilized for reducing the wetting issue of MD. This review paper discusses the fundamentals and roles of surface energy and hierarchical structures on both the hydrophobic characteristics and wetting tolerance of MD membranes. Designing stable antiwetting interfaces with their basic working principle is illustrated with high scientific discussions. The capability of antiwetting surfaces in terms of their self-cleaning properties has also been demonstrated. This comprehensive review paper can be utilized as the fundamental basis for developing antiwetting surfaces to minimize fouling, as well as the wetting issue in the MD process

A Case Study On Big Bath Earnings Management With Large Shareholder Changes With A Focus On The Setting Of Loan Loss Allowances For A Savings Bank

The management performance of a bank is highly affected by bad debt the bank has written off related to loan receivables. When this happens, discretionary action regarding the setting of the allowance for loan losses is enabled, through which the big bath phenomenon often occurs. The present study investigates this big bath phenomenon. In particular, it attempts to determine whether it occurs when the allowance for loan losses is set during a specific period of time – namely the period in which large shareholders change and the new shareholder brings a capital influx. An examination was carried out through a case analysis for a savings bank. Z Savings Bank was selected, and for comparison and analysis, similar savings banks were studied. From 2002 to 2014, large shareholders at Z Savings Bank changed four times. The analysis revealed that when individual-to-individual shareholder changes took place, the big bath phenomenon did not occur. However, in two cases, one in 2011 and the other in 2014, individual-to-company shareholder changes took place. In these two cases, management performance showed high variations, and it was confirmed that the typical big bath phenomenon occurred. According to the analysis, this was due to an environmental factor that caused distressed debts to be reflected at their maximum value. This was done via an inspection process that was triggered when the capital held by the large companies – both Korean and foreign – was brought in. Specifically, the bad debt being written off and the allowances for loan losses were intentionally exposed in the accounting in order to provide transparency when the shareholder changes took place. This phenomenon occurred because the Financial Supervisory Commission reinforced the obligatory allowance-setting rate to ensure the soundness of assets

Competition between B-Z and B-L transitions in a single DNA molecule: Computational studies

Under negative torsion, DNA adopts left-handed helical forms, such as Z-DNA and L-DNA. Using the random copolymer model developed for a wormlike chain, we represent a single DNA molecule with structural heterogeneity as a helical chain consisting of monomers which can be characterized by different helical senses and pitches. By Monte Carlo simulation, where we take into account bending and twist fluctuations explicitly, we study sequence dependence of B-Z transitions under torsional stress and tension focusing on the interaction with B-L transitions. We consider core sequences, (GC)(n) repeats or (TG)(n) repeats, which can interconvert between the right-handed B form and the left-handed Z form, imbedded in a random sequence, which can convert to left-handed L form with different (tension dependent) helical pitch. We show that Z-DNA formation from the (GC)(n) sequence is always supported by unwinding torsional stress but Z-DNA formation from the (TG)(n) sequence, which are more costly to convert but numerous, can be strongly influenced by the quenched disorder in the surrounding random sequence.National Research Foundation NRF-2012 R1A1A3013044 NRF-2014R1A1A2055681NRF-2012R1A1A2021736IBS-R023-D1NRF-2015R1A2A2A01005916Chemistr

Experimental Study About An Amount Of Oil Charge On Electric Driven Scroll Compressor For Electric Vehicle

The main roles of the oil in scroll compressor are to lubricate the friction parts, and to reduce the compressor driving power and to improve the durability of the compressor consequently. However, it has another side that could make decrease the efficiency of the heat exchanger and whole air-conditioning system. In the case of compressor, if the oil is charged too much, the compressor driving power will be increased and the compressor overall efficiency will be decreased. Therefore, the initial charge amount of the oil in the compressor should be determined appropriately. This study has performed to optimize the initial charge amount of the oil on the electric driven scroll compressor for eco-friendly vehicles. We have used a electric driven scroll compressor has a back pressure chamber which make up of oil. About the various initial charge amount of the oil, The remaining oil was evaluated at each of steps of the complex durability test and each of conditions of performance test. The various initial charge amount of the oil had increased 20g at a time from 40g to 120g. Through the evaluation, the optimum amount of the Oil is determined by the back pressure. So we have found the optimum amount of Oil. Also the performance of a system is compared through pulldown test in the actual air conditioning system. We could get the optimal amount of oil which has the best performance in air conditioning system

Investigation of a Gas Hydrate Dissociation-Energy-Based Quick-Freezing Treatment for Sludge Cell Lysis and Dewatering

A gas Hydrate dissociation-energy-based Quick-Freezing treatment (HbQF) was applied for sewage sludge cell rupture and dewatering. Carbon dioxide (CO2) and water (H2O) molecules in sewage create CO2 gas hydrates, and subsequently the sludge rapidly freezes by releasing the applied pressure. Cell rupture was observed through a viability evaluation and leachate analysis. The decreased ratios of live cell to dead cells, increased osmotic pressure, and increased conductivity showed cell lysis and release of electrolytes via HbQF. The change in physicochemical properties of the samples resulting from HbQF was investigated via zeta potential measurement, rheological analysis, and particle size measurement. The HbQF treatment could not reduce the sludge water content when combined with membrane-based filtration post-treatment because of the pore blocking of fractured and lysed cells; however, it could achieve sludge microbial cell rupture, disinfection, and floc disintegration, causing enhanced reduction of water content and enhanced dewatering capability via a sedimentation post process. Furthermore, the organic-rich materials released by the cell rupture, investigated via the analysis of protein, polysaccharide, total organic carbon, and total nitrogen, may be returned to a biological treatment system or (an) aerobic digester to increase treatment efficiency

Experimental Investigations On The Performance Improvement Of Oil-gas Separator In Electric Driven Scroll Compressor For Eco-friendly Vehicles

Experimental research about the oil-gas separator was conducted in order to improve the performance of electric driven scroll compressors used in eco-friendly HEV/EVs. The compressor used in the tests was “back pressure†method electric driven scroll compressors using oil. To maintain adequate back pressure, an oil separator in the discharge chamber is required. It is inevitable that the refrigerant passing an oil separator inside a discharge chamber experiences a pressure drop. This pressure drop increases input power, resulting in some decrease of the COP of the compressor. Various parameters of the oil separator— the length of vortex finders; installation angle; and the inlet, outlet diameters— related to the pressure drop were considered. The installation angle and the outlet diameters had no significant effect on the pressure drop; however, a pressure drop decrease in relation to the length of the vortex finder and the inlet diameter was confirmed. As the vortex finder length decreased and the inlet diameter increased, the input power of the compressor is decreased about 4.12% and the COP is increased about 2.66% by the reduction of the pressure drop

Transcriptional Regulator TonEBP Mediates Oxidative Damages in Ischemic Kidney Injury

TonEBP (tonicity-responsive enhancer binding protein) is a transcriptional regulator whose expression is elevated in response to various forms of stress including hyperglycemia, inflammation, and hypoxia. Here we investigated the role of TonEBP in acute kidney injury (AKI) using a line of TonEBP haplo-deficient mice subjected to bilateral renal ischemia followed by reperfusion (I/R). In the TonEBP haplo-deficient animals, induction of TonEBP, oxidative stress, inflammation, cell death, and functional injury in the kidney in response to I/R were all reduced. Analyses of renal transcriptome revealed that genes in several cellular pathways including peroxisome and mitochondrial inner membrane were suppressed in response to I/R, and the suppression was relieved in the TonEBP deficiency. Production of reactive oxygen species (ROS) and the cellular injury was reproduced in a renal epithelial cell line in response to hypoxia, ATP depletion, or hydrogen peroxide. The knockdown of TonEBP reduced ROS production and cellular injury in correlation with increased expression of the suppressed genes. The cellular injury was also blocked by inhibitors of necrosis. These results demonstrate that ischemic insult suppresses many genes involved in cellular metabolism leading to local oxidative stress by way of TonEBP induction. Thus, TonEBP is a promising target to prevent AKI

In-situ fabrication of cobalt-doped SrFe2As2 thin films by using pulsed laser deposition with excimer laser

The remarkably high superconducting transition temperature and upper critical field of iron(Fe)-based layered superconductors, despite ferromagnetic material base, open the prospect for superconducting electronics. However, success in superconducting electronics has been limited because of difficulties in fabricating high-quality thin films. We report the growth of high-quality c-axis-oriented cobalt(Co)-doped SrFe2As2 thin films with bulk superconductivity by using an in-situ pulsed laser deposition technique with a 248-nm-wavelength KrF excimer laser and an arsenic(As)-rich phase target. The temperature and field dependences of the magnetization showing strong diamagnetism and transport critical current density with superior Jc-H performance are reported. These results provide necessary information for practical applications of Fe-based superconductors.Comment: 8 pages, 3figures. to be published at Appl. Phys. Let