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Three central themes in the study of the phenomenon of resistive switching are the nature of the conducting phase, why it forms, and how it forms. In this study, the answers to all three questions are provided by performing switching experiments in situ in a transmission electron microscope on thin films of the model system polycrystalline SrTiO

A new approach for detecting localized electrically failed particles in an electrode for Li-ion batteries (LIBs) in scanning electron microscope (SEM) is introduced to investigate the critical factor for the capacity fading of Si-alloy/graphite-blended anodes. The present study proposes straightforward techniques for diagnosing failure commonly called the voltage contrast image (VCI) consist of two different methods, the passive voltage contrast (PVC) and the active voltage contrast (AVC). These methods widely used in semiconductor industries can be successfully adapted to the electrode degradation analysis for LIBs. These methods directly indicate electron charging effect on electrically disconnected particles caused by mechanical crack or the organic solid electrolyte interphases the mechanisms of capacity fading during the cycle while electrodes are being observed by SEM. The VCI results of the Si-alloy/graphite-blended anodes, particularly focusing on graphite particles, show that graphite particles near the current collector tend to be isolated individually whereas ones away from current collector keep their connectivity. These results give insights that which part should be improved to develop battery performance.

Pure tin (Sn) metal nano-powder is investigated as a high capacity negative electrode for rechargeable all-solid-state Li-ion batteries. Sn is used to form a fully dense network intertwining with solid electrolyte negating necessary conductive additive. Galvanostatic cycling of the Sn composite electrode delivers a reversible capacity 800 mAh g −1 of Sn with a constant coulombic efficiency over 99.2%.Wereportontheeffectofpressureandrateuponthedelithiationmechanics,drawingcorrelationsbetweenSnvolumeincrease factors and stress accumulation over the course of Sn-Li phase transformations. Due to the fabricated electrode microstructure, we are able to operate the cell at ambient pressure conditions ‐ the next step toward commercialization of the solid-state battery. We believe that this initial work provides new opportunities to study the electrochemical expansion of Sn with the inclusion of rigid electrolyte particles. © The Author(s) 2015. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any

This study reports a direct observation on the crack behavior of lithiated Si wafer. Three different Si wafers with , and axes are investigated, to compare the crack behaviors of different orientation Si wafers. Electrochemically induced cracks in each orientated wafer have dissimilar crack behaviors, because the initiations and propagations of cracks are strongly affected by their orientation and strain energy release rate. It is also found that triangular humps and cracks are formed in the (111) wafer, which are discovered for the first time by in this study. Considering that volume expansion, cracks, and pulverizations of Si are the main issues for the commercial use of Si for Li ion battery, this study provides important insight that is relevant to the design of advanced Si anode materials.

We report observations of microstructural changes in {100} and {110} oriented silicon wafers during initial lithiation under relatively high current densities. Evolution of the microstructure during lithiation was found to depend on the crystallographic orientation of the silicon wafers. In {110} silicon wafers, the phase boundary between silicon and LixSi remained flat and parallel to the surface. In contrast, lithiation of the {100} oriented substrate resulted in a complex vein-like microstructure of LixSi in a crystalline silicon matrix. A simple calculation demonstrates that the formation of such structures is energetically unfavorable in the absence of defects due to the large hydrostatic stresses that develop. However, TEM observations revealed micro-cracks in the {100} silicon wafer, which can create fast diffusion paths for lithium and contribute to the formation of a complex vein-like LixSi network. This defect-induced microstructure can significantly affect the subsequent delithiation and following cycles, resulting in degradation of the electrode.

Electric-powered transportation requires an efficient, low-cost, and safe energy storage system with high energy density and power capability. Despite its high specific capacity, the current commercially available cathode material for today's state-of-art Li-ion batteries, lithium nickel–manganese–cobalt oxide Li[Ni 1/3 Mn 1/3 Co 1/3 ]O 2 (NMC), suffers from poor cycle life for high temperature operation and marginal rate capability resulting from irreversible degradation of the cathode material upon cycling. Using an atomic-scale surface engineering, the performance of Li[Ni 1/3 Mn 1/3 Co 1/3 ]O 2 in terms of rate capability and high temperature cycle-life is significantly improved. The Al 2 O 3 coating deposited by atomic layer deposition (ALD) dramatically reduces the degradation in cell conductivity and reaction kinetics. This durable ultra-thin Al 2 O 3 -ALD coating layer also improves stability for the NMC at an elevated temperature (55 °C). The experimental results suggest that a highly durable and safe cathode material enabled by atomic-scale surface modification could meet the demanding performance and safety requirements of next-generation electric vehicles.

Three central themes in the study of the phenomenon of resistive switching are the nature of the conducting phase, why it forms, and how it forms. In this study, the answers to all three questions are provided by performing switching experiments in situ in a transmission electron microscope on thin films of the model system polycrystalline SrTiO3 . On the basis of high-resolution transmission electron microscopy, electron-energy-loss spectroscopy and in situ current-voltage measurements, the conducting phase is identified to be SrTi11 O20 . This phase is only observed at specific grain boundaries, and a Ruddlesden-Popper phase, Sr3 Ti2 O7 , is typically observed adjacent to the conducting phase. These results allow not only the proposal that filament formation in this system has a thermodynamic origin-it is driven by electrochemical polarization and the local oxygen activity in the film decreasing below a critical value-but also the deduction of a phase diagram for strongly reduced SrTiO3 . Furthermore, why many conducting filaments are nucleated at one electrode but only one filament wins the race to the opposite electrode is also explained. The work thus provides detailed insights into the origin and mechanisms of filament generation and rupture.

D. Molina Piper, T. A. Yersak, S.-B. Son, Prof. S.-H. Lee Department of Mechanical Engineering University of Colorado at Boulder, 80309 USA E-mail: sehee.lee@colorado.edu D. Molina Piper, Dr. C. Ban, Dr. A. C. DillonNational Renewable Energy Laboratory 1617 Cole Boulevard, 80401 USA S.-B. Son, S. C. Kim, C. S. Kang, Prof. K. H. OhDepartment of Material Science and Engineering Seoul National University, 151-742 Korea

We report that a solid-state battery architecture enables the reversible, four electron storage of fully utilized solvothermally synthesized cubic-FeS2 (pyrite). With a sulfide based glass electrolyte we successfully confine electro-active species and permit the safe use of a lithium metal anode. These FeS2/Li solid-state cells deliver a theoretical specific capacity of 894 mAh g−1 at 60 °C. We find that nanoparticles of orthorhombic-FeS2 (marcasite) are generated upon recharge at 30–60 °C which explains a coincident change in rate kinetics.

This paper reports a Si-Ti-Ni ternary alloy developed for commercial application as an anode material for lithium ion batteries. Our alloy exhibits a stable capacity above 900 mAh g−1 after 50 cycles and a high coulombic efficiency of up to 99.7% during cycling. To enable a highly reversible nano-Si anode, melt spinning is employed to embed nano-Si particles in a Ti4Ni4Si7 matrix. The Ti4Ni4Si7 matrix fulfills two important purposes. First, it reduces the maximum stress evolved in the nano-Si particles by applying a compressive stress to mechanically confine Si expansion during lithiation. And second, the Ti4Ni4Si7 matrix is a good mixed conductor that isolates nano-Si from the liquid electrolyte, thus preventing parasitic reactions responsible for the formation of a solid electrolyte interphase. Given that a coulombic efficiency above 99.5% is rarely reported for Si based anode materials, this alloy's performance suggests a promising new approach to engineering Si anode materials.

In this study, formaldehyde in various fisheries products was previously derivatized with acetylacetone and subsequently analyzed by using HPLC-PDA. The formaldehyde contents ranged from 0.07 to 73.74 mg/kg. The compound was significantly higher in both mollusks (0.34-12.38 mg/kg) and crustaceans (0.09-73.74 mg/kg) than in fish (0.07-3.35 mg/kg) and shellfish (0.50-3.90 mg/kg). This difference was due to storage time and temperature. In general, fish and shellfish are sold live or in refrigerated form with shorter a shelf-life, but mollusks and crustaceans are distributed in cold or frozen systems with a longer shelf-life. Using food intake data from a report of the National Health and Nutrition Survey, the daily human exposure level to formaldehyde was 0.58% of the ADI. The results from this study might provide fundamental information to confirm naturally-originating or fraudulent formaldehyde treatment in fisheries products.

In order to rapidly screen for the virulence factor that produces pathogenic Escherichia coli in food, we have developed multiplex polymerase chain reaction (PCR) assays. The multiplex PCR assays detect 4 pathogenic genes of enterohaemorrhagic E. coli (EHEC), enterotoxigenic E. coli (ETEC), enteropathogenic E. coli (EPEC), and enteroinvasive E. coli (EIEC). This allows for the generation of specific fragments 150, 179, 218, 401, 465, 584, and 881 bp for VT1, ST, LT, 16S rRNA, inV, VT2, and eaeA genes, respectively. The detection limit of 3 log CFU/mL for eaeA, LT, VT1, VT2, 4 log CFU/mL for inV, 6 log CFU/mL for ST by single PCR, while 5 log CFU/mL for VT1, VT2, 6 log CFU/mL for eaeA, LT, 7 log CFU/mL for ST, inV by multiplex PCR. This optimized detection method of pathogenic E. coli can be used as supportive data to revise the microbiological analytical manuals for the Korean Food Code.

Propionic acid levels in fermented products, non-fermented products and foodstuffs, and medicinal herbs were analyzed total 263 samples retailed in Korean market. Propionic acid was detected in some Korean traditional fermented products such as salted and fermented fish sauce, Chunggukjang and salted and fermented fish. A small amount of propionic acid was also detected in fermented soybean paste, soy sauce, seasoned soybean paste, vinegar and fermented milk. Significantly, propionic acid in vinegar showed high levels among fermented products (P

Establishment of simultaneous analysis method and monitoring for individually analyzing residual eight ergosterol biosynthesis inhibitors, EBI (difenoconazole, diniconazole, fenarimol, fenbuconazole, hexaconazole, myclobutanil, nuarimol and paclobutrazol) pesticides in commercial agricultural products, were conducted. The simultaneous analysis method for the pesticides was established using a GC/MS/MS for EBI pesticides. Residual amount of those pesticides were investigated in 989 commercial agricultural products (fifteen kinds of cereal grains, vegetables, beans, nuts, fruits and mushrooms) from seven metropolitan cities and eight provinces. In EBI pesticides analysis, linearity of GC/MS/MS analysis was 0.9974-0.9992, and that of recoveries were 86-135% with relative standard deviations (RSD)

A novel nano-scale manipulator capable of handling low-dimensional materials with three-dimensional linear motion, gripping action, and push–pull action of the gripper was developed for an in situ experiment in transmission electron microscopy. X-Y-Z positioning and push–pull action were accomplished by a piezotubing system, combined with a specially designed assembly stage that consisted of a lever-action gripping tip backed by a push–pull piezostack. The gripper tip consisted of tungsten wire fabricated by electrochemical etching followed by a focused ion beam process. Performance of the nano-scale manipulator was demonstrated in a grab-and-pick test of a single silver nanowire and in an in situ tensile test of a pearlitic steel sample with a specific orientation.

Although it has been known that pomegranate (Punica granatum L.) contains several steroid hormones, concrete experimental proofs about that have not been published until now. In order to identify and evaluate the contents of steroid hormones including estrone in pomegranate, we analyzed pomegranate seed, fruit juice and commercial preparations. We developed a reproducible and sensitive method for separation and identification of steroid hormones in pomegranate samples using both high performance liquid chromatography (HPLC)–PDA and gas chromatography (GC)–MS. In case of HPLC, an isocratic elution method using 35% aqueous acetonitrile solution at 1.0 ml/min with photodiode-array (PDA) detection at 225 nm and 254 nm was found to optimally separate and identify the steroid hormones from the pomegranate samples with a run time of less than 30 min. The pomegranate samples were comparatively analyzed to the HPLC results by GC/FID or GC/MS detection on a HP-1 (30 m length, 0.32 mm I.D.) with helium as carrier gas under the oven temperature control as follows: start 220 °C for 5 min, raising 5 °C per min, final 280 °C for 10 min. The HPLC and GC methods were successfully applied to the identification of steroid hormones in pomegranate samples. Our results suggested that there were no steroid estrogens including estrone, estradiol and testosterone in pomegranate seed, fruit juice and preparations. Consequently, we assumed that the previously reported analysts of pomegranate were misunderstood their analytical results according to either the estrogen-like effects or similarity of peak retention time and Rf values in experiments.

An activated carbon was modified by impregnating with various acids or bases. The effects of adsorption capacity and impregnated contents on the textural properties of the impregnated activated carbons (IACs) were investigated. Furthermore, VOC adsorption and desorption experiments were carried out to determine the relationship between the adsorption capacity and chemical properties of the adsorbents. The effects of various parameters such VOC concentration, aspect ratio, flow rate, and impregnated contents were investigated. High adsorption capacity for the selected VOCs was obtained over 1 wt.% H 3 PO 4 /AC (1 wt.% PA/AC). As a result, IAC was found to be effective for VOC removal by adsorption with the potential for repeated use through desorption by simple heat treatment.

Selective catalytic reduction (SCR) among the approaches for alleviating NOx emission was much attracted. Zeolites have the advantage for adsorption of propene, and noble metal catalyst has the advantage for oxidation of NO to NO 2 . Pt (or Au)/Al 2 O 3 (or SiO 2 ) were used as the lower layer of double wash-coated monolith catalysts. Zeolites (H-mordenite or ZSM-5) were coated as the upper layer. The catalytic performance of the double wash-coated catalyst was, remarkably, improved. Also, temperature window was shifted to lower temperature and broadened. It was known that the combined noble metal monolith catalyst with zeolite was very effective in removing NOx by SCR with hydrocarbons.

Atenolol and related compounds found in raw materials and commercial products were analyzed by reversed-phase high-performance liquid chromatography. A mixed solution of phosphate buffer (3.4 g/l, pH 3.0), tetrahydrofurane and methanol (800:20:180, v/v/v) including sodium octanesulfonate (1 g/l) and tetrabutylammonium-hydrogensulfate (0.4 g/l) was used as mobile phase at the flow rate of 0.25 ml/min. Detection was carried out at UV 226 nm. Atenolol related compounds, such as bis ether, tertiary amine and blocker acid were identified by comparing the retention time of the standard. The within-day and between-day precisions of the separated compounds were less than 1.2% and 3.4%, respectively. The contents of related compounds of the tested samples were under the limit prescribed in the European Pharmacopoeia. The pattern of the related compounds showed that atenolol raw materials and products could be classified in three different groups, indicating that the materials originated from different source or treated in different way.

With the Sunshine policy, exchange of materials and cultures inter Koreas has been broadened and expectancy of reunification is getting higher. Especially, medical supplies and medicines are one of the biggest parts in the exchange goods. So, preparing an unified official drug standard preparing new medical administration system is required. We compared the Korean pharmacopoeia with North Korean Pharmacopoeia. Two pharmacopoeias have been developed in different direction and have many differences in the nomenclature and format. In this study, we compared general notices, general rules for preparations and crude drugs, monographs, general tests, processes and apparatus.

Drug excipients are material used in the formulation of pharmacologically active drugs. They have a variety of roles including dilutents/fillers/bulking agents, binders/adhesives, propellant, disintegrants, lubricants/dlidants, colors, flavors, coating agents, polising agents, fragrance, sweeteening agent, polymers and waxes. Excipient should be inert or inactive and does not interfere with the test. Nowadays within industry there has been a recent surge of interest in novel excipient for novel dosage forms. The purpose of the review is to introduce the administration systems of drug excipient about kinds, matters to be attended to change of excipients.

Nonproprietary name may be used without restriction by the public at large and can be called common name, generic name. Nomenclature agencies exist in US, Great Britain, Japan and so on. The agencies maintain liaison with one another in an effort to secure the wide adoption of the most appropriate and universally acceptable designation for each drug. To prevent the confusion which arises when several nonproprietary names are used for a single drug, either in the same country or in several different countries, the WHO has assumed the responsibility of coordination existing nomenclature at the international level. In this study, the nomenclature for new drugs and the terminology to harmonize specifications for revision of Korean Pharmacopoeia (KP) were established.

IVIVC (In vitro/in vivo correlation) is useful for predicting in vivo results from in vitro data. The aim of this study was to develop IVIVC of sustained release diltiazem. For this purpose, three types of diltiazem tablets with different in vitro dissolution rates were prepared. An in vitro dissolution testing method comprising of paddle apparatus, 50 rpm, water as dissolution medium was developed. Under these condition, we demonstrated that AUCinf could be predicted by evaluating (time dissolved 70%) in vitro since the in vivo AUCinf was correlated with the in vitro (r=-0.9981).

Plan-view and cross-sectional transmission electron microscopy images show the microstructural properties of GaN thin films grown on graphene layers, including dislocation types and density, crystalline orientation and grain boundaries. The roles of ZnO nanowalls and GaN intermediate layers in the heteroepitaxial growth of GaN on graphene, revealed by cross-sectional transmission electron microscopy, are also discussed.

Pure Fe–C pearlite was heat-treated and selectively etched to extract [0 0 1]- and [1 0 0]-oriented single crystalline cementite sheets. The elastic properties of the shaped cementite were measured in a simple, in situ bending test system set up inside the scanning electron microscope using a micronewton-range force sensor. The Young’s modulus experimentally measured from a single crystal sheet was lower than the value obtained from theoretical calculation.

Gold has rarely been utilized as a catalytic component because of its poor affinity to chemical species. It is however known that nanosized gold particles promote the dissociation of oxygen or hydrogen. In this study, alumina-supported metal oxide catalysts were prepared by impregnation method and applied to methanol oxidation. The dispersion form and size of the gold particles were observed by transmission electron microscopy (TEM). In the results, the maximum catalytic activity was obtained over the ZnO/Al2O3 catalyst, and the optimum loading was 4 wt%. Furthermore, nanosized gold particles at various loadings were added to ZnO/Al2O3 catalyst by deposition method. The gold particles on Au/ZnO/Al2O3 catalyst were well dispersed and the catalyst activity was remarkably increased compared to ZnO/Al2O3 catalyst. The role of gold particles in the increased catalytic activity is discussed and a possible mechanism is presented.

Resistive switching memory (ReRAM) or Memristor attracted considerable attention due to its technological potential for non-volatile memory and various applications. However, the mechanism is still not resolved clearly because of its difficulties of identifying a conducting channel particularly at oxide systems. Objective of this paper is elucidation of resistive switching mechanism by identifying and analyzing behavior of filaments in-situ in SrTiO3 (STO) and NiO/TiO2 oxides systems. ReRAM can be classified according to different criteria; it can be categorized into unipolar and bipolar systems according to current-voltage (I-V) characteristics, or Electrochemical metallization (ECM), Valence change memory (VCM), and Thermochemical memory (TCM) in terms of different aspects in participation of electrodes in operation. Most of the models that have been presented to explain resistive switching phenomena are based on the formation of filaments, no matter which category their system belongs to. Thus, in order to unravel the mechanism of resistive switching, identifying structure of the filament has its great significance. It has been readily observed in case of the ECM because the filaments, injected metal ion from electrode, are distinguished from electrolyte or insulator. On the contrary, filaments of VCM and TCM have yet to be understood thoroughly. In this paper, our focus will be on the system that could be classified into VCM/TCM. Though grain boundary, defect percolation were suggested as promising candidates of filament at these systems, they have not been clearly verified yet due to their unknown structure, limited size of nanometer scale, and geometry covered by matrix. As the structure and behavior of filament is still controversial, substantial amount of papers reported to unveil the mechanism of resistive switching employed many hypotheses. Here, we identified and analyzed the filament structure at oxide resistive switching system of Pt/SrTiO3/Pt and Pt/NiO/TiO2/Pt, employing in-situ scanning tunneling microscope (STM) / TEM holder. STM tip was in contact with oxide thin film in the TEM and scanned over the region of interest to probe filaments. The filaments could have been detected because of their high conductivity. Consequently, new conducting crystal structure, 2nd phase, is observed in the STO, NiO/TiO2 thin film. Similar as we reported before that 2nd phases of metallic crystals, Magneli TinO2n-1 (n>=4), are generated in the TiO2 thin film as conducting channels. After probing filaments, high-resolution (HR) images and electron-energy loss spectroscopy (EELS) were acquired at corresponding area for determining its crystal and electronic structure respectively. HR images were further analyzed to investigate orientation relationship between the filaments and matrix. EEL spectrum were compared with a simulation data obtained from first principle calculation using Vienna Ab initio simulation package. Furthermore, the sample was turned ‘on’ and ‘off’ repeatedly in-situ and behavior of filament is tracked. The resistance state of the sample was correlated to the structure transformation of filaments. SrTiO3 thin film of 60 nm was deposited by pulsed laser deposition process under oxygen atmosphere and NiO/TiO2 thin film of 50nm was deposited by atomic layer deposition. Platinum pad was exploited for both top and bottom electrodes. Cross-section TEM sample was prepared by focused ion beam. Gatan image filter equipped TEM, F20, was used for in-situ STM/TEM, HR images and EELS.

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In this study we embed phase pure natural cubic-FeS 2 (pyrite) in a stabilized polyacrylonitrile (PAN) matrix. The PAN matrix confi nes FeS 2 ’s electroactive species (Fe 0 and S n 2 ) for good reversibility and effi ciency. Additionally, the stabilized PAN matrix can accommodate the 160% volume expansion of FeS 2 upon full discharge because it is not fully carbonized. At room temperature, our PAN-FeS 2 electrode delivers a specifi c capacity of 470 mAh g 1 on its 50th discharge. Using high-resolution transmission electron microscopy (HRTEM) we confi rm that FeS 2 particles are embedded in the PAN matrix and that FeS 2 ’s mobile electroactive species are confi ned during cycling. We also observe the formation of orthorhombic-FeS 2 at full charge, which validates the results of our previous all-solid-state FeS 2 battery study. The energy density of conventional Li-ion batteries with LiMO 2 (M = transition metal) cathodes and graphitic anodes is approaching a practical upper limit after two decades of optimization. In order to improve the energy density of Li-ion batteries further, new cathodes must be developed with capacities that compare to those of advanced anodes such as Si. [ 1 ] The FeS 2 conversion chemistry is a promising candidate to replace the LiMO 2 intercalation chemistry because FeS 2 is inexpensive, energy dense, and environmentally benign. The four electron reduction of cubic-FeS 2 (pyrite) with lithium (FeS 2 + 4Li + + 4e  → Fe + 2Li 2 S) provides a specifi c capacity of 894 mAh g 1 , whereas, the very best LiMO 2 intercalation cathodes can only provide 200 mAh g 1 . [ 2‐4 ] For these reasons Energizer popularized the FeS 2 /Li chemistry as a primary battery, [ 5 ] but a secondary FeS 2 /

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