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We analyzed the quality characteristics of wheat-free, gluten-free dough, steam-treated dough, and cooked noodles. Dough was prepared from soaked-and-dried soybean (SDS) powder amended with 10%, 25%, or 40% psyllium husk; the SDS was prepared by soaking soybeans for 12 h at room temperature and hot air drying at 60°C for 24 h. Dough was then steam-treated at 120°C for 5, 10, or 15 min and subsequently formed into noodles. Dough and noodle can be made using SDS powder and psyllium husk powder, but it is difficult to maintain noodle shape after cooking without steam treatment. Steam treatment improved the texture of the dough, enabling noodle production. The hardness, gumminess, springiness, cohesiveness, and chewiness of the steam-treated dough were improved compared to nonsteamed dough, yielding a texture similar to wheat flour dough. Moreover, the dough cross-section became denser after steam treatment. As the cooking time increased, the hardness, gumminess, cohesiveness, and chewiness of cooked noodles decreased, and the springiness of cooked noodles increased by increasing of water absorption rate; overall, their form was maintained. Therefore, steam-treated psyllium husk-containing dough enables noodle production without the addition of gluten.

Calix[4]arenes 1 and 2 bearing two diametrical triazolyl anthracenes on the lower rim have been synthesized as a dual optical sensor and a fluorogenic cation sensor, respectively. UV/vis spectroscopy and fluorescence spectroscopy analyses revealed that receptors 1 and 2 are able to recognize divalent cations such as Ca2+, Zn2+, Ba2+, Hg2+, and Pb2+ with a significantly higher preference for Hg2+, giving rise to different color and fluorescence changes. It was also confirmed by 1H NMR spectroscopy and fluorescence spectroscopy analyses carried out in acetonitrile that receptor 1 binds the cations via different binding modes resulting in distinct colorimetric and fluorometric responses.

An acid–base junction flow battery (ABJFB) is a new type of energy conversion system using neutralization and water dissociation in the presence of acid and base electrolytes. The bipolar membrane (BPM) is a core component in determining the performance of the ABJFB. In particular, the development of an anion exchange layer (AEL) is essential to improve the performance of the BPM. In the present study, we fabricated a novel BPM composed of aligned ion channels of a quaternary aminated poly (2,6-dimethyl-1,4-phenylene oxide) (QPPO) layer and a pellicle of the cation exchange layer (CEL). The results showed that the through-plane conductivity of the QPPO membrane prepared under an AC electric field improved from 26.78 to 120.83 mS cm−1, owing to the aligned ion channels. The fabricated BPM based on the aligned QPPO membrane showed the remarkably improved performance of water dissociation and neutralization reactions in the presence of acid and base electrolytes without delamination. The ABJFB assembled with the optimized BPM showed a high power density of 3.85 mW cm−2 under a high strength acid/base of 2 N H2SO4 and NaOH solutions. In addition, we first performed a long-term operation of 60 cycles with a high coulombic efficiency of 98.9%, energy efficiency of 55.5%, and voltage efficiency of 56.1% under 2 N H2SO4 and NaOH at a high current density of 4 mA cm−2.

Light-emitting diodes (LEDs) based on metal halide perovskite nanocrystals (MHP NCs) have been rapidly developed to reach external quantum efficiencies of up to 22% with their defect-tolerant nature and extremely high color purity (full width half maxima

The seagrass ecosystem is among the most efficient natural carbon sinks that can contribute to climate change mitigation. However, little is known about the effects of coastal nutrient enrichment caused by anthropogenic activities and/or climate change on the capacity of the seagrass blue carbon sink. Our experimental manipulations of sediment nutrient enrichment shifted the blue carbon sink capabilities of seagrass meadows. Sediment nutrient enrichment significantly increased the nutrient content of seagrass litter, stimulating the decomposition of rhizome + root litter by ∼10% while retarding the decomposition of leaf litter by ∼5%. Sediment N + P enrichment increased seagrass growth and litter production, while enrichment of N or P alone did not. Organic carbon (Corg) stocks in the surface sediments (0-5 cm) were 34% higher than those in the control with N + P enrichment due to high litter production and the low decomposition rate of nutrient-enriched leaf litter. However, Corg stocks in the subsurface sediments (5-20 cm) did not increase with sediment nutrient enrichment, which is likely due to accelerated decomposition of rhizome + root litter. Our findings suggest that nutrient loading in coastal sediments alters the blue carbon sink and storage capacities in seagrass meadows by changing the rates of carbon sequestration and decomposition.

A ternary hybrid photocatalyst consisting of Au@CeO2 core–shell nanostructures coated with ultralow Pt-functionalized surface contents (Au@CeO2–Pt) was synthesized using a facile hydrothermal method. The Pt-decorated Au@CeO2 core–shell photocatalyst had a large Brunauer–Emmett–Teller (BET) surface area (86.50 m2 g−1) with an abundance of catalytically active sites. The hydrogen production rate over Au@CeO2–Pt under visible light (8.7 μmol mg−1 h−1) was much higher than that observed over binary Au@CeO2 (3.9 μmol mg−1 h−1) and pure CeO2 (0.9 μmol mg−1 h−1) catalysts. Enhancement of the hydrogen evolution reaction (HER) was attributed mainly to the surface plasmon resonance (SPR) effect of the Au cores, which was highly advantageous for light absorption and conversion. In addition, the Pt co-catalyst served as an electron sink that accepted photogenerated electrons migrating from the Au@CeO2 core–shells. This extended the lifetime of the photogenerated charge carriers and resulted in HER activity that was superior to that of the Pt-free photocatalysts. The large BET surface area of the ternary core–shell nanostructure and the presence of many catalytically active sites also enhanced the HER performance.

Fabrication of high-conductivity ion exchange membranes (IEMs) is crucial to improve the performance of non-aqueous vanadium redox flow batteries (NAVRFBs). In the present work, anion exchange membranes with high-conductivity were fabricated by aligning ion channels of the polymer electrolyte impregnated in porous polytetrafluoroethylene (PTFE) under electric fields. It was observed that the ion channels of the polymer electrolyte were uniformly orientated in the atomic-force microscopy image. Its morphological change could minimize detouring of the transport of BF4− ions. The results showed through-plane conductivity was improved from 12.7 to 33.1 mS cm−1. The dimensional properties of the fabricated membranes were also enhanced compared with its cast membrane owing to the reinforcing effect of the substrate. Especially, the NAVRFB assembled with the optimized membrane showed increased capacities, with a 97% coulombic efficiency and 70% energy efficiency at 80 mA cm−2. Furthermore, the optimized membrane made it possible to operate the NAVRFB at 120 mA cm−2. Its operating current density was 120 times higher than that of a frequently used AHA membrane for RFBs.

A mesh-type dimensionally stable anode (DSA) consisting of ruthenium and iridium with low catalyst loading was prepared as an oxygen evolution reaction catalyst in acidic and alkaline media. The electrodeposition (ED) conditions, i.e., applied current density and total cycle number, and ED solutions with different precursor ratios of ruthenium to iridium are examined to fabricate various DSAs with a uniform thickness, and the effect of the iridium content on the catalytic activity is investigated. Among various DSA electrodes, the DSA electrode without iridium exhibits the highest activity and stability in the acidic medium owing to the high ratio of ruthenium. Conversely, the DSA electrode obtained using the ED solution with the ratio of 8:2 exhibits the highest performance in the alkaline medium. This is because the DSA electrode without iridium showed low stability, which is attributed to the dissolution of ruthenium oxide in the alkaline medium. In addition, two large-scale DSA electrodes optimized in the acidic and alkaline electrolytes show excellent performance, indicating the feasibility of the application of this electrode in practical electrolysis.

We made precipitated nano-ceria (∼5 nm) on the surface of the catalyst by heat treatment of Ce-supersaturated amorphous CeTiOx to improve the oxygen storage properties of CeO2. The catalysts were prepared by sol-gel methods and TiO2 nanoparticles were preferentially generated as a core material to form selective Ce-supersaturated structure on the catalyst surface. Reaction temperature and amount of doping element are optimized to induce selective crystallization of CeO2. Ce Ce (2nd shell) bond around 0.38 nm of Ce L3-edge extended X-ray absorption fine structure is reduced and nanostructure of precipitated ceria on the surface is observed by HREM. The catalyst is present as amorphous with precipitated nano-CeO2 on the surface. The de-NOx efficiency of the catalyst, which has precipitated CeO2, improves by ∼50% owing to the simultaneous reactions of the nano CeO2 and the amorphous CeTiOx.

The formation of highly dispersed Pt nanoclusters supported on zeolite-templated carbon (PtNC/ZTC) by a facile electrochemical method as an electrocatalyst for the oxygen reduction reaction (ORR) is reported. The uniform micropores of ZTC serve as nanocages to stabilize the PtNCs with a sharp size distribution of 0.8–1.5 nm. The resultant PtNC/ZTC exhibits excellent catalytic activity for the ORR due to the small size of the Pt clusters and high accessibility of the active sites through the abundant micropores in ZTC.

Nitrogen-doped microporous carbons with various compositions of pyridinic, pyrrolic, and graphitic N species were synthesized by the pyrolysis of pyrrole using Ca2+ ion-exchanged Y zeolite as a template. The Ca2+ ions in zeolite pores served as a catalyst to lower the carbonization temperature, resolving the problems associated with high carbonization temperature, such as inhomogeneous carbon deposition, easy breakage of weak C–N bonds, and preferential formation of thermodynamically stable graphitic N species. The resultant carbons exhibited a 3D microporous structure with high surface area and uniform micropore diameters, as well as high N content (5–6 wt%). Taking advantage of the lowered carbonization temperature, the ratio of the N species was modulated by the carbonization temperature, while a similar pore structure of the carbons was maintained. These N-doped carbons were used to investigate the efficiency of each N species on the electrochemical oxygen reduction, without the influences from the porous structure of the carbons. The results of this electrochemical investigation indicate that the graphitic N was more effective in enhancing the oxygen-reduction performance of the 3D microporous carbons than pyridinic N.

Existing gels are mostly polar, whose nature limits their role in soft devices. The intermolecular interactions of nonpolar polymer-liquid system are typically weak, which makes the gel brittle. Here we report highly soft and transparent nonpolar organogels. Even though their elements are only carbon and hydrogen, their elastic modulus, transparency, and stretchability are comparable to common soft hydrogels. A key strategy is introducing aromatic interaction into the polymer-solvent system, resulting in a high swelling ratio that enables efficient plasticization of the polymer networks. As a proof of applicability, soft perovskite nanocomposites are synthesized, where the nonpolar environment of organogels enables stable formation and preservation of highly concentrated perovskite nanocrystals, showing high photoluminescence efficiency (~99.8%) after water-exposure and environmental stabilities against air, water, acid, base, heat, light, and mechanical deformation. Their superb properties enable the demonstration of soft electroluminescent devices that stably emit bright and pure green light under diverse deformations., Perovskite nanocrystals are promising emitters but suffer from environmental instabilities. Here, Park et al. introduce aromatic nonpolar organogels as a soft passivating matrix of perovskites, demonstrating highly efficient and environmentally stable luminescent nanocomposites.

Zeolite templating is a versatile synthesis route to produce various types of ordered microporous carbon. However, the synthesis thus so far has been limited to the use of wide-pore zeolites with 12-membered ring (12MR) pore mouths or more because of the diffusion limitation of organic carbon precursors. Here, we report an extension of the carbon synthesis to a 10MR zeolite, through acetylene carbonization in Li+-ion-exchanged ZSM-5 zeolite. The promoting effect of the Li+ ions on the carbon synthesis could be relevant to the carbide-forming property of the element, similar to the recently reported cases of La3+, Y3+, and Ca2+ cations in 12MR zeolites. The resultant carbon exhibited an ordered array of ultramicropores of 0.5 nm diameter, which corresponded to the thickness of the zeolite framework. Because of the ultramicroporosity, the ZSM-5-templated carbon exhibited an anomalously high value of surface-area-normalized electrical double-layer capacitance.

Polycyclic aromatic hydrocarbons (PAHs) attract much attention for applications to organic light-emitting diodes, field-effect transistors, and photovoltaic cells. The current synthetic approaches to PAHs involve high-temperature flash pyrolysis or complicated step-by-step organic reactions, which lead to low yields of PAHs. Herein, we report a facile and scalable synthesis of PAHs, which is carried out simply by flowing acetylene gas into zeolite under mild heating, typically at 400 °C and generates the products of 0.30 g g–1 zeolite. PAHs are synthesized via acetylene polymerization inside Ca2+-ion-exchanged Linde type A (LTA) zeolite, of which the α-cage puts a limit on the product molecular size as a confined-space nanoreactor. The resultant product after the removal of the zeolite framework exhibits brilliant white fluorescence emission in N-methylpyrrolidone solution. The product is separated into four different color emitters (violet, blue, green, and orange) by column chromatography. Detailed char...

Nafion, the most popular cation exchange membrane, was cast while charged in an electric field to enhance the proton conductivity of the membrane. This electrically modified Nafion shows dramatically increased conductivity compared to the pristine membrane. The enhancement of proton conductivity is a result of changes in the membrane nanostructure, as shown by transmission electron microscopy, X-ray diffraction, and Fourier transform-IR spectroscopy. In particular, the membrane crystallinity was increased by 7% in the electrically modified membrane. As a result of the structural changes, the conductivities were enhanced from 0.137 to 0.231 S cm−1 in the in-plane aligned membrane and from 0.111 to 0.276 S cm−1 in the through-plane aligned membrane. Furthermore, the through-plane conductivity has been calibrated using a pressure control system for accurate comparison with reference values. Through the calibration process, the membrane resistance has been separated from the measured resistance, which is the sum of the membrane and interfacial resistances. Thus, the real proton conductivity of Nafion has been calculated in the through-plane direction. In this study, we have succeeded in improving the ionic conductivity of Nafion to its highest value to the best of our knowledge. Based on our results, not only can the improved Nafion be used itself, but this technique can be applied to other kinds of ion exchange membranes for use in energy systems.

The redox properties of CeO2-WO3 mixed oxide supported on multi-walled carbon nanotubes (MWCNTs) and TiO2 were investigated in terms of valence state and active oxygen species. Ce–W/CNT and Ce–W/TiO2 were synthesized by impregnation method to support CeO2-WO3 mixed oxide on CNTs and TiO2. The interplanar distance of CeO2 in Ce–W/CNT was measured to be 0.316 nm by TEM and SAED pattern analysis, which was larger than that of Ce–W/TiO2 (0.310 nm), indicating the lattice expansion due to Ce3+ formation. Since the F2g and Ov peaks in Raman spectrum of Ce–W/CNT were broader than those of Ce–W/TiO2, it implied the increased oxygen vacancies of CeO2 supported on CNTs. In XPS analysis, Ce3+/(Ce4++Ce3+) ratios in Ce–W/CNT and Ce–W/TiO2 were 42.28% and 28.60%, and Oα/(Oα+Oβ) ratios were 29.07% and 17.29%, respectively. The redox properties of the catalysts were investigated by H2-TPR analysis. The reduction peak of Ce–W/CNT shifted to a lower temperature compared to Ce–W/TiO2, and H2 consumption increased by 1.91 mmol/g, increasing the redox properties. The reduction in the valence state of Ce4+ was caused by charge transfer between CNT and CeO2-WO3 mixed oxide, and the reduction promoted the formation of oxygen vacancies and active oxygen species.

Indium-tin oxide is considered a highly promising mixed-metal oxide system, because it shows good performance in various industrial processes. Therefore, it will be of great importance to explore the possibility of obtaining new In-Sn oxides with controlled contents whose properties could be tailored. However, In or Sn content in In-Sn oxides has generally been restricted to

Carbon dot-Au nanoraspberries (Cdot-Au NRs) were synthesized by a simple one-pot process using Cdots as initiators to direct the dendritic growth of Au via room temperature chemical reduction of HAuCl 4 by formic acid. We evaluated the resulting Cdot-Au NR as a counter electrode material for ZnO nanowire/CdS/CdSe quantum dot-sensitized solar cells (QDSCs). The counter electrode employing Cdot-Au NRs exhibited higher electrocatalytic activity, lower charger-transfer resistance, and larger exchange current density than commonly used Au-sputtered counter electrodes. The power conversion efficiency of the cell was improved to 5.4%, in comparison to efficiencies of 3.6% and 0.18% shown by cells employing Au-sputtered and Cdot counter electrodes, respectively. These features render Cdot-Au NRs as highly promising counter electrode materials for QDSCs.

We report amphoteric polybenzimidazole (PBI) membranes with tailored nanoporous structures for vanadium redox flow batteries (VRFBs). The amphoteric nanoporous membrane has restricted the crossover of vanadium species and instantaneously allowed for the transport of protons owing to the positively charged polybenzimidazolium polymer backbone. The selected membrane shows a proton/vanadium (H/V) selectivity of about 133, which is considerably higher than those stated in previous reports. This reflects its high coulombic efficiency of 99.4%, energy efficiency of 78.2%, and low capacity decay rate of 0.27% per cycle when compared to 93.0%, 78.9%, and 0.58% per cycle of Nafion-117, respectively.

A thermally stable and flame-retardant separator is proposed to improve the safety of lithium ion batteries. The separator is prepared by dip-coating both sides of a conventional tri-layer polyolefin separator with brominated poly(2,6-dimethyl-1,4-phenylene oxide) (BPPO). Significantly reduced thermal shrinkage and flammability are exhibited without decreases in the pore size or porosity of the conventional separator. By using the BPPO-coated separator, an electrochemical half-cell composed of a lithium metal anode and a LiCoO2 cathode are successively tested. The resulting stable cycle performances are demonstrated. It is expected that the BPPO-coated separator can be a capable candidate as a separator for the safe of lithium ion batteries.

Crystalline anatase TiO2 with nanosponge-like mesoporous morphologies was solvothermally synthesized following the recently reported route using random copolymer (4-vinylphenol and methyl methacrylate) as structure-directing agent. In particular, the synthesis conditions were varied over a wide range of synthesis gel compositions. Crystallinity of the titania products was checked with X-ray powder diffraction. Mesopore diameters, pore volume and specific surface area were analyzed using nitrogen adsorption. The result provided proper synthesis domains for highly mesoporous titania materials. The mesoporous materials were evaluated as supports for catalytic Pt nanoparticles to apply for alcohol-to-aldehyde partial oxidation reactions.

A low-resistance ion-exchange membrane is essential to achieve the high-performance energy conversion or storage systems. The formation methods for low-resistance membranes are various; one of the methods is the ion channel alignment of an ion-exchange membrane under a direct current (DC) electric field. In this study, we suggest a more effective alignment method than the process with the DC electric field. First, an ion-exchange membrane was prepared under a pulsed electric field [alternating current (AC) mode] to enhance the effectiveness of the alignment. The membrane properties and the performance in reverse electrodialysis (RED) were then examined to assess the membrane resistance and ion selectivity. The results show that the membrane electrical resistance (MER) had a lower value of 0.86 Ω cm(2) for the AC membrane than 2.13 Ω cm(2) observed for the DC membrane and 4.30 Ω cm(2) observed for the pristine membrane. Furthermore, RED achieved 1.34 W/m(2) of maximum power density for the AC membrane, whereas that for the DC membrane was found to be 1.14 W/m(2) [a RED stack assembled with CMX, used as a commercial cation-exchange membrane (CEM), showed 1.07 W/m(2)]. Thereby, the novel preparation process for a remarkable low-resistance membrane with high ion selectivity was demonstrated.

Cation exchange membranes (CEMs) have attracted tremendous attention in electrochemical energy conversion and storage systems owing to their high proton conductivity and chemical stability. However, applications of CEMs suffer from a number of disadvantages such as requirement of costly platinum catalyst, and high crossover of fuels or positively charged redox species due to the electro-osmotic drag. Anion exchange membranes (AEMs) have shown promising characteristics to overcome some of the problems associated with CEMs; the advantages of AEMs being selective transport anionic charge carriers, lower crossover of cationic redox couples, and facile reaction kinetics in energy conversion processes. These unique properties of AEMs result mainly from the density and distribution of positively charged functional groups, along with a macromolecular polymer backbone. As a result, there has been an increasing demand for the development of AEMs with better selectivity, higher chemical stability and conductivity, and a lot of work has been carried out in this area. The aim of this review is to discuss developments in the synthesis and applications of AEMs in the field of electrochemical energy conversion and storage, on which many researchers have been working in recent years.

Zr-doped MnO x /CeO 2 –TiO 2 for high temperature stability was investigated in terms of its dispersion and oxidation state. Aggregation of cerium oxide was observed in MnO x /CeO 2 –TiO 2 , but the Zr-doped catalyst was well dispersed. An increase of the Mn 4 + /Mn 3 + ratio was confirmed with a Zr addition through valence state analysis. De-NOx efficiency of the catalyst was increased to 40–45% by Zr addition at low temperature (150–200 °C). The substitution of Zr led the catalyst to improve the de-NOx efficiency, with a high dispersion and MnO 2 ratio.

In this paper organic thin film transistors (OTFTs) are directly fabricated on fabric substrates consisting of Polyethylene Terephthalate (PET) fibers. A key process is coating the polymer layers on the fabric in order to reduce the large surface roughness of the fabric substrate. Two polymers, i.e. polyurethane (PU) and photo-acryl (PA), are used to reduce the large surface roughness and simultaneously improve the process compatibility of the layers with the subsequent OTFTs processes while also retaining the original flexibility of the fabric. The surface roughness of the PU/PA-coated fabric is significantly reduced to 0.3 μm. Furthermore, the original flexibility of the PET fabric remained after coating of the PU/PA polymer layers. The mobility of the OTFTs fabricated on the PU-PA coated fabric substrate is 0.05 ± 0.02 cm 2 /V s when three PA layers and 90 nm thick pentacene layer were used. The performance does not vary even after 30,000 bending test.

Department of Food and Nutrition, College of Health Sciences, Korea University, Seoul 136-703, KoreaReceived January 2, 2013, Accepted March 13, 2013Food is a common source of chromium (Cr) exposure. However, it is difficult to analyze Cr in complex foodmatrices by using inductively coupled plasma mass spectrometry (ICP-MS) because the major isotope

Numerous efforts have been made to resolve the organic fouling issue in seawater reverse osmosis (SWRO) desalination plants. However, SWRO membranes still suffer fouling in practice. This study proposed a fundamental approach to gain insight into the actual fouling phenomenon. First, humic substances were isolated from seawater (SeaHSs) and characterized by FTIR, 1H-NMR, and MS-IT-TOF. SeaHSs demonstrated some distinctions in average molecular weight, proton distribution, and functional groups compared to humic substances originating from river water and soil which have been popularly utilized to study organic fouling. SeaHSs were then used to study, for the first time, the organic fouling behaviors of SWRO membranes in comparison with Aldrich humic acid (AHA) and Suwannee River natural organic matter (SuNOM). AHA induced the most severe fouling while SeaHSs caused the lowest level of fouling, consistent with the postulation from structural differences. In addition, to further demonstrate the fouling mechanism at a molecular level, unused membranes, fouled membranes, and cleaned membranes (after being fouled) were analyzed exclusively using contact angles and FTIR. The analysis helped to rationalize the variations in fouling behaviors and the distinctions of different types of organic foulants on those variations. The results provide valuable information for all researchers involved in the field in order that they become more cautious in selecting model organic foulants for studying organic fouling in SWRO desalination plants.

An AMOLED panel driven by an OTFT-backplane is an attractive display because OTFTs and OLEDs use organic materials with unique characteristics such as low temperature and solution processing ability, and thus are able to implement the key features of future displays. In this study we applied some printing technologies to fabricate an OTFT-backplane for AMOLEDs. Screen printing combined with photolithography with Ag ink was used for the gate electrodes and scan bus lines and contact pads. Ag metal lines with a width of 20 μm and thickness of 60 nm and resistivity of 3.0 × 10 −5 Ω cm were achieved. Inkjet printing was applied to deposit TIPS-pentacene as an organic semiconductor. The OTFT-backplane using the Ag gate electrodes and TIPS-pentacene exhibited uniform performance over 17,500 pixels on a 7 in. panel. The mobility was 0.31 ± 0.05 cm 2 /V s with a deviation of 17%. The AMOLED panel successfully demonstrated its ability to display patterns.

Heat shock protein (Hsp)70 is a molecular chaperone that maintains protein homoeostasis during cellular stress through two opposing mechanisms: protein refolding and degradation. However, the mechanisms by which Hsp70 balances these opposing functions under stress conditions remain unknown. Here, we demonstrate that Hsp70 preferentially facilitates protein refolding after stress, gradually switching to protein degradation via a mechanism dependent on ARD1-mediated Hsp70 acetylation. During the early stress response, Hsp70 is immediately acetylated by ARD1 at K77, and the acetylated Hsp70 binds to the co-chaperone Hop to allow protein refolding. Thereafter, Hsp70 is deacetylated and binds to the ubiquitin ligase protein CHIP to complete protein degradation during later stages. This switch is required for the maintenance of protein homoeostasis and ultimately rescues cells from stress-induced cell death in vitro and in vivo. Therefore, ARD1-mediated Hsp70 acetylation is a regulatory mechanism that temporally balances protein refolding/degradation in response to stress., The chaperone Hsp70 has a dual role, promoting both protein refolding and protein degradation. Seo and Park et al. show that Hsp70 acetylation enhances protein refolding after stress, and that subsequent deacetylation progressively promotes ubiquitin ligase binding and protein degradation.

A highly sensitive tyrosinase (TYR)-based amperometric biosensor is prepared using biologically designed gold nanowires (AuNWs) for pesticide detection. The AuNWs were synthesized by dodecapeptide Midas-11 and were modified with the formation of self-assembled monolayer (SAM), followed by covalent binding with TYR. The prepared TYR-AuNWs-SPCE (screen printed carbon electrode) was compared with bare, AuNWs-, modified-AuNWs-SPCE by the measurement of cyclic voltammetry. The quantitative relationship between the inhibition percentage and the pesticide concentration at the TYR-AuNWs-SPCE was obtained by measuring the current response in various concentrations of pesticides. The reasonable detection range of parathion was determined to be 0.1 ppt through 10 ppb (R2=0.990) with 0.087 ppt of detection limits. The higher sensitivity and wider detection range of the TYR-based biosensor was achieved by the use of biologically synthesized AuNWs.

A simple electrochemical approach is presented to quantitatively predict activation energy and mass transfer coefficient from a polarization curve of polymer electrolyte fuel cells to examine the membrane-electrode assembly (MEA) performance. It is assumed that the initial voltage drop at open circuit voltage is due to kinetic activation energy and that the current loss at short circuit current is due to mass transfer resistance. Accordingly, voltage drop in the activation polarization is converted into a change in the Gibbs free energy to determine the activation energy requirement. The mass transfer coefficient for current losses is derived from Fick’s law, based on the mass transfer limitation of oxygen at the oxygen reduction reaction sites. Case studies from the literature show reasonable correlations to the operating conditions, thereby providing a useful tool for prediction of the preliminary values of the activation energy and mass transfer coefficient for an MEA under various conditions.

Interests on the polarity reversal have increased to prevent or minimize membrane fouling and scaling during the operation of electromembrane processes. In this study, the influence of the operation conditions on the process efficiency was investigated in the electrodeionization reversal (EDIR) system with an electrodeionization with the polarity reversal. The removal efficiencies of divalent cations (Mg2+ and Ca2+) kept high value without scale formation on the membrane surface. Through the EDIR operation, the process performance was affected by polarity reversal periods, and the operating polarity reversal period was determined to 40 min or shorter in this study. In the long term EDIR experiments with different cation exchange membranes, the homogeneous membranes showed marginally higher removal efficiency compared to the heterogeneous membrane. The scale powders and the surface of scaled membrane were analyzed using electron microscopes and it was observed that the scales formed as carbonate of divalent cations. The EDIR results showed the feasibility of the EDIR system for use in water softening process without significant scale formation even in a relatively high concentration.

New composite proton exchange membrane was prepared by mixing a 1-methyl-2-pyrrolidone (NMP) solution of sulfonated poly(2,6-dimethyl-1,4-phenylene oxide) (SPPO) in sodium form and brominated poly(2,6-dimethyl-1,4-phenylene oxide) (BPPO) for hydrophilic-hydrophobic balance, then casting the solution as a thin film, evaporating the solvent, and treating the membrane with aqueous hydrochloric acid. The resulting membranes were subsequently characterized using FTIR-ATR, SEM-EDXA, and TGA instrumentation as well as measurements of basic properties such as ion exchange capacity (IEC), water uptake, proton conductivity, methanol permeability, and single cell performance. Water uptake, IEC, proton conductivity, and methanol permeability all increased with a corresponding increase of SPPO content. By properly compromising the conductivity and methanol permeability, membranes with 60–80 wt % SPPO content exhibited comparable proton conductivity to that of Nafion® 117, with only half the methanol permeability, thereby demonstrating higher single cell performance. The membranes developed in this study could thus be a suitable candidate electrolyte for proton exchange membrane fuel cells (PEMFCs). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Fish meat extract (FME) desalination via electrodialysis (ED) was performed and the changes of important parameters such as membrane stack potential, brix, pH, and electrical conductivity were examined for a quantitative evaluation. The change of electrical conductivity in diluted or concentrated solutions showed that the mineral ions contained in the FME could be effectively removed. The characterization of membrane fouling indicated that the organic/inorganic components deposited, respectively, on the surfaces of anion/cation exchange membrane and resulted in the increase of membrane electrical resistance. Ion chromatograph (IC) analysis showed that the main mineral ions, such as Na+ and Cl+ ions contained in the FM E, were removed about 82.3% at an average current efficiency of around 77.9% via ED. By considering the removal rate of mineral ions and current efficiency, the feasibility of FME desalination via ED was proved.

DNA has recently been used as a programmable ‘smart’ building block for the assembly of a wide range of nanostructures. It remains difficult, however, to construct DNA assemblies that are also functional. Incorporating RNA is a promising strategy to circumvent this issue as RNA is structurally related to DNA but exhibits rich chemical, structural and functional diversities. However, only a few examples of rationally designed RNA structures have been reported. Herein, we describe a simple, general strategy for the de novo design of nanostructures in which the self-assembly of RNA strands is programmed by DNA strands. To demonstrate the versatility of this approach, we have designed and constructed three different RNA–DNA hybrid branched nanomotifs (tiles), which readily assemble into one-dimensional nanofibres, extended two-dimensional arrays and a discrete three-dimensional object. The current strategy could enable the integration of the precise programmability of DNA with the rich functionality of RNA.

One of the key transport parameter—permeability, is being used as an intrinsic characteristic of membrane for reverse osmosis process prediction. In this study, the prediction of reverse osmosis process in terms of boron rejection was carried out in two steps. First, the permeability of boron existing as boric acid B(OH)3 and as metaborate ion B(OH)4− through seawater reverse osmosis membranes was estimated in three types of feed matrix: DI water, NaCl and artificial seawater. The second step was to develop a computer program using boric and borate permeabilities as inputs to predict the boron rejection at different operating conditions. The governing equations were derived from the solution–diffusion model. The effect of temperature was quantitatively determined employing a representative constant and incorporated with the program. The prediction showed good agreement with experimental data obtained from a lab-scale plate-frame type reverse osmosis system.

Interest in desalination using membrane processes has increased with the growth of membrane science and technology. Fouling of ion exchange membranes is one of the most significant considerations in the operation of the electrodialysis desalination process. The influence of the adsorption capacity of foulants on the fouling potential was investigated in an electrodialysis desalination process in the presence of negatively charged organic foulants, humate, bovine serum albumin and sodium dodecylbenzenesulfonate (SDBS). The SDBS showed higher adsorption capacity on the anion exchange membrane surface than the other two foulants in the adsorption equilibrium experiments. Of three different organic foulants, the SDBS had a more severe fouling effect on the process performance in the electrodialysis desalination of synthetic brackish water, with irreversible fouling due to the high adsorption capacity. The study clearly showed that the adsorption capacity affects the fouling potential of the electrodialysis desalination process.

An electroenzymatic method is developed to degrade 2-chlorobiphenyl (2-CB) with horseradish peroxidase (HRP) immobilized glassy carbon electrode as the working electrode. Cyclic voltametric studies were carried out to understand the redox reactions involved. An applied potential of −0.5 V was found suitable for the degradation of 2-CB. During degradation, dechlorination of 2-CB was confirmed by the measurement of chloride ion concentration in the reaction mixture, and was found almost equimolar to the initial 2-CB concentration. Chloride concentration was 0.53 ppm at the end of reaction while the initial 2-CB concentration was 3.15 ppm. That means that almost 97% of the chlorine in 2-CB sample was liberated. Total organic carbon (TOC) measurements revealed that almost 83% 2-CB was mineralized. Degraded products were analyzed by GC-MS to find reaction intermediates. However, no peak could be detected except 2-CB. Therefore, the most probable route of degradation is through dechlorination followed by biphenyl ring cleavage and mineralization.

Electrical impedance spectroscopy was used for the characterization of electroregeneration in a continuous electrodeionization (CEDI) system packed with cation-exchange resin (CIX). CEDI process usually operates in two regimes of enhanced transfer and electroregeneration. The current efficiency decreased in the second regime of a CEDI system due to the water dissociation. Therefore, it is necessary to minimize the second regime to maximize the current efficiency by controlling the operating parameters even though the second regime is essential for regeneration of the resin. It was suggested to monitor the ionic state of the bed during the operation by observing current distribution along the column. The measurement of the resistance of CIX beads at high frequency, based on the equivalent circuit, provided information on the extent of electrical regeneration of the bed. The optimal current density was estimated at the minimized area of second regime, and the operation at the optimal current density showed the 100% of metal removal, indicating the effectiveness of this method.

Performances of electromembrane systems were investigated for removal of the hardness materials in a tap water. Six cells of ED, EDR, and EDIR systems with an electrode area of 12.5cm x 8.0 cm were operated. The results showed scaling formation due to water dissociation on the surface of cation exchange membrane, but EDR and EDIR enabled to avoid the scaling problem. EDIR operation lowered the resistance and power consumption compared to EDR due to the conductance of ion exchange resins. This study demonstrated the feasibility of EDR and EDIR processes for water softening.

Acrylic acid (AA)-g-polypropylene (PP) membranes were prepared by grafting AA on to a microporous PP membrane via plasma-induced graft polymerization. The grafting of AA to the PP membrane was investigated using Fourier transform infrared spectroscopy (FTIR). Pore-filling of the membranes was confirmed by field emission-scanning electron microscopy (FESEM) and energy dispersing X-ray (EDX). Ion exchange capacity (IEC), membrane electric resistance, transport number and water content were measured and analyzed as a function of grafting reaction time. The prepared AA-g-PP membranes showed moderate electrochemical properties as a cation-exchange membrane. In particular, membranes with a degree of grafting of 155% showed good electrical properties, with an IEC of 2.77 mmol/g dry membrane, an electric resistance of 0.4 Ω cm2 and a transport number of 0.96. Chronopotentiometric measurements indicated that AA-g-PP membranes, with a high IEC had a sufficient conducting region in the membrane. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007

Electrodialysis is known to be a useful membrane process for water desalination. The limiting current density (LCD) in the electrodialysis process is an important parameter which determines the electrical resistance and the current utilization. Usually, LCD depends on membrane and solution properties as well as on the electrodialysis stack construction and various operational parameters such as the flow velocity of the diluate solution. Therefore, a reliable determination of LCD is required for designing an efficient electrodialysis plant. In this study, LCD was measured in an electrodialysis flow cell system of given geometry and spacer configuration as a function of the linear velocity. The coefficients a and b of an equation describing LCD as a function of the linear flow velocity of the diluate solution, ilim=aCub, were determined from a plot of the measured LCD over the electrolyte concentration versus the linear velocity on a double logarithmic scale. It was found that the coefficient b was related to the hydrodynamic conditions, while the coefficient a was affected by the cell geometry, electrolyte concentration and the membrane properties.

Polypropylene membranes were modified by the plasma etching of SO2, SO2O2, or SO2H2O, followed by the plasma polymerization coating of SO2/acetylene. The conditions for SO2 plasma etching were optimized by the measurement of the ion-exchange capacity (IEC) as a function of the plasma-etching power (10–30 W), gas pressure (40–60 mTorr), and treatment time (15–120 s). For the plasma etching of SO2O2 and SO2H2O, only the pressure ratio (SO2/O2 and SO2/H2O) was optimized under the optimized conditions determined from SO2 plasma etching. Plasma etching was then combined with the plasma polymerization coating of SO2/acetylene, for which the conditions were again optimized by the measurement of the IEC as a function of the plasma power (10–40 W), chamber pressure (50–200 mTorr), SO2/acetylene ratio (15/135–60/90), and treatment time (0–10 min). Next, the electrical resistance and water uptake were evaluated. The modified membranes were also analyzed with scanning electron microscopy, whereas plasma polymer coatings were characterized with Fourier transform infrared/attenuated total reflection. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3692–3699, 2006

Efficiencies of two lypolytic enzymes (fungal cutinase and yeast esterase) in malathion degradation were investigated. Surprisingly, degradation rate of malathion by fungal cutinase was very high, i.e. almost 60% of initial malathion (500 mg l(-1)) was decomposed within 0.5 h, and nearly 50% of the degraded malathion disappeared within initial 15 min. With the yeast esterase, despite the same concentration, more than 65% of malathion remained even after 2-day treatment. During enzymatic degradation of malathion, two malathion-derived compounds were detected, and time-course changes in composition were also monitored. In the degradation by both fungal cutinase and yeast esterase, two additional organic chemicals were produced from malathion: malathion monoacid (MMA) and malathion diacid (MDA) by ester hydrolysis. Final chemical composition after 2 d was significantly dependent on the enzyme used. Fungal cutinase produced MDA as a major degradation compound. However in the malathion degradation by yeast esterase, an isomer of MMA was produced in abundance in addition to MDA. Toxic effects of malathion and its final degradation products were investigated using various recombinant bioluminescent bacteria. As a result, the degradation products (including MMA) by esterase severely caused membrane damage and inhibition of protein synthesis in bacterial cells, while in the fungal cutinase processes, malathion was significantly degraded to non-toxic MDA after the extended period (2 days).

The transport of cobalt ion in a continuous electrodeionization (CEDI) system was investigated in terms of electrochemical properties of ion exchange textile. The porous plug model and an extended Nernst‐Plank equation were applied to describe the transport of Co2+ through an ion exchange textile. The transport characteristics of Co2+ during CEDI operation suggested the transport mechanism was due mainly to the increased current induced by the high conductivity in the ion exchange textile, not accelerated ionic mobility. This study suggested the important parameter for the high performance of the CEDI system is the conductivity of the ion exchange media.

A supported liquid membrane (SLM), impregnated with tricaprylmethyl ammonium chloride (Aliquat 336) as a carrier, was investigated for separating and recovering Cr(VI) in aqueous solutions containing Cr(III). It was found that the transport of Cr(VI) through the SLM was dominated by membrane diffusion and that the Aliquat 336 in the SLM played a key role in the selective transport of Cr(VI) while o‐nitrophenyl octyl ether (NPOE) assisting mobility of the ion–carrier complex in the membrane. The maximum recovery of Cr(VI) in the test solution containing Cr(III) was 93.2% with a permeability of 1.01 × 10−3 cm/s through the SLM made of 0.0735 g poly(vinyl chloride) (PVC), 0.1471 mL NPOE, and 5.43 × 10−5 mol Aliquat 336 for a sheet of 24.6 cm2. The permeability of Cr(VI) was not influenced by concentrations of Cr(VI) and cationic interferences in the feed solution, except for Cr(III). Selective recovery of Cr(VI) in the presence of anionic interferences and Cr(III) was attained reasonably when the ni...

An RO-CEDI (Reverse osmosis-continuous electrodeionization) hybrid process was investigated to pro- duce high purity water. The RO system, with an effective membrane area of 1.1 m 2 , was operated using tap water with conductivity of 64 µs·cm −1 , and the CEDI system experiments were carried out in a cell-pair stack consisting of 3 com- partments. During the parametric study of the RO-CEDI hybrid system, the optimal operating conditions were deter- mined based on the water purity. The electrical resistivity and water dissociation of the ion exchange resins and ion exchange membrane were verified as the key mechanisms of the CEDI system in the water purification. The produced water met the quality requirements as a make-up water in a nuclear power plant with a resistivity of 10-16.7 MΩ·cm.