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Electrolytes that achieve highest Li Coulombic efficiency display quantifiably higher rates of electrochemical Li+ exchange. The effect is attributed to their improved SEI and better-percolated Li deposits that boost Li+ exchange as the cell cycles.

Pesticide residues in vegetables (watercress, mustard green, choy sum, daikon, okra, and yam) from Mekong Delta, Vietnam were analysed by liquid chromatography-tandem mass spectroscopy (LC-MS/MS). QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) extraction, matrix-matched calibration, and dynamic multiple reaction monitoring methods were used. The linear range used was 5 - 200 ng/mL, resulting in R2 > 0.99. The recovery was satisfactory with values within 74.47 - 116.93%, and the RSD was < 15% for most compounds. The percentage of samples with residues above the maximum residue levels (MRLs) was 59%. Pesticide residues were detected above their MRLs in samples of watercress (47%), mustard green (80%), choy sum (83%), daikon (87%), and yam (60%). The results indicated the prevalence of pesticide residues in commonly consumed vegetables in Vietnam, and emphasised the urgent need to develop comprehensive intervention measures to reduce the potential health risk to consumers.

Magnesium silicate is a porous material with a large specific surface area and is easily adsorbed. In particular, it is widely used commercially because it is very effective for adsorbing Na+, K+ ions and other catalysts. However, if the powder is used as an adsorbent as is, there are disadvantages, in that the adsorbed material is easily lost during the adsorption action and becomes difficult to recover. In this study, magnesium silicate was used as an adsorbent to remove pollutants (CO2) from the atmosphere. In addition, in order to overcome the disadvantages of using a powder adsorbent material, an inorganic binder (clay) and a reinforcing agent (glass fiber) were added to prepare a molded article which imparted strength to the adsorbent material. Changes in the properties of the adsorbent were confirmed. Changes in the physicochemical properties of the adsorbed material according to the calcination temperature, from 400 to 800°C, were confirmed. In addition, it was confirmed that a molded body with 15 wt% inorganic binder and 4 wt% reinforcing agent had a specific surface area of about 87 m²/g and a strength of 4.63 N. The prepared molded article could adsorb about 0.41 mmol/g of CO2 at atmospheric pressure, confirming its potential use as a CO2 adsorbent.

In Vietnam, Physalis angulata L. is a wild species growing throughout the country that is often used in traditional medicine. The aim of study was to quantify seven major compounds, including phenolic acids (chlorogenic acid, caffeic acid, p-coumaric acid) and flavonoids (rutin, quercitrin, quercetin, and kaempferol) in three aerial parts of P. angulata. Chromatographic separation was carried out on a Kromasil C18 column (150 mm × 4.6 mm i.d., 5 µm) with a gradient elution of 0.1% formic acid in acetonitrile, 0.2% ammonium acetate/0.1% formic acid in water and methanol at a flow rate of 1.0 mL/min; detection was at 250 and 300 nm. The limits of detection and quantification were in the ranges of 0.1–0.3 and 0.3–1.0 µg/mL, respectively. The validated method was successfully applied to analyze active compounds in P. angulata and may be a useful tool for quality control of this plant.

A simple and inexpensive liquid chromatography diode array detector (LC-DAD) procedure has been developed to analyse food dyes in beverages, candies, jams, salted fish, Chinese sausage, and cake. A reverse stationary phase provided sufficient selectivity and chromatographic performance for the separation of 11 water-soluble dyes (tartrazine, amaranth, indigo carmine, ponceau 4R, sunset yellow, allura red, carmoisine, fast green FCF (Food green 3), brilliant blue, quinoline yellow, and indocyanine green). The samples were extracted with 1% ammonium solutions and acetonitrile, purified, and concentrated using a C18 solid-phase extraction (SPE) cartridge for beverages, and weak anion exchange SPE cartridge for solid samples. They were determined using a reverse-phase C18 column with gradient elution of 0.2% ammonium acetate buffer, and acetonitrile as the mobile phase. Multiple-specific wavelengths were used to monitor the dyes in the visible range to provide higher sensitivity and an expanded scope for a large number of analytes. The limit of detection and limit of quantification of the dyes were in the range of 0.2 - 0.5 and 0.5 - 1.0 µg/mL, respectively. The precision of the method ranged from 2.71 to 6.31%, while recovery ranged from 90.8 to 105.6%. The validated method was successfully applied to the quantitative analysis of 11 water-soluble dyes in 36 commercial products obtained from the local supermarket. Application to the analysis of beverages and food samples available to consumers proved that the described methods are suitable for the routine analysis of dyes in food products containing a broad range of dyes.

Despite being a leading candidate to meet stringent energy targets of Li-ion batteries, the lithium (Li) metal anode has yet to achieve Coulombic efficiency (CE) requirements for long cycle life (>99.9%), particularly at high rates (>1 C). These limitations derive from the native solid electrolyte interphase (SEI) which, among multiple functions, stabilizes and protects deposited Li. The SEI also plays a critical role in regulating Li+ exchange between the electrolyte and the electrode, but quantification of this effect has been non-straightforward, and a general relationship between Li+ exchange and CE has not been clearly elucidated to date. Using electrochemical impedance and voltammetry, we report self-consistent Li+ exchange values of native SEIs over a range of relevant electrolytes with CE spanning 78.0% to >99%. CE and its retention at high rates are found to be positively correlated with the rate of SEI Li+ exchange. Additionally, Li+ exchange rates increased during cycling in high-CE electrolytes, in some cases by an order of magnitude to exceed 10 mA/cm2, whereas for low-CE electrolytes they remained low (1 mA/cm2).

The realization of high performance Ni-rich layered cathodes remains a challenge because of the multiple degradation factors that concurrently operate during battery cycling. In particular, depletion of oxygen charge and consequent lattice-oxygen instability at deep charge state accelerate the subsequent chemomechanical degradation mechanisms. Among the proposed methodologies, doping has proven to be effective in enhancing the cathode cycle life by stabilizing the layered structure. Herein, we achieved the electrochemically stabilized Ni-rich LiNi0.92Co0.04Mn0.04O2 through Zr doping, resulting in a 15% increase of the capacity retention after 100 cycles. In-depth investigations are conducted to unveil the effects of Zr doping on the layered cathode, and in particular, the critical role of Zr doping on the lattice oxygen stability is systematically studied. By combining state-of-the-art magnetometer characterization, X-ray analysis, and first-principles calculation, we reveal that Zr doping positively contributes the to lattice oxygen stability by alleviating the oxygen charge loss at deep charge, thereby improving the cathode electrochemical reversibility. Our findings provide an insight into the Zr doping mechanism and help to design Ni-rich layered oxides for future applications.

Although replacing biomass, (e.g., wood chips and pellets), with thinning wood and herbaceous biomass is eco-friendly and economically advantageous, their direct utilization in plant boilers is associated with ash-related challenges, including slagging and fouling. The aim of this study is to determine the effects of ash removal treatment (ashless biomass (ALB)) in the context of solid fuel power plant boilers. Ash was removed via neutralization of metal ions and carboxylic acids contained in the biomass ash. The ash removal rate of K, Na, Cl was indicated by assessing the total biomass before and after ash removal treatment, via XRF analysis. Co-combustion with sub-bituminous coal and ALB-treated biomass was analyzed using a drop tube furnace and revealed that NOx and SOx values converged converge toward an approximate 10 ppm error, whereas the Unburned Carbon (UBC) data did not exhibit a specific trend. Factors associated with slagging and fouling, (capture efficiency (CE), and energy based growth rate (GRE)) were calculated. All biomass samples without pretreatment exhibited V-shaped variation. Conversely, for ashless biomass (ALB) samples, CE and GRE gradually decreased. Thus, the ALB technique may minimize slagging and fouling in a boiler, thus, reducing internal corrosion associated with ash deposition and enhancing the economic operation of boilers.

Objective: To develop a simple and accurate HPLC-DAD method for simultaneous determination, the content of major components: limonin, evodiamine, and rutaecarpine in Evodiae fructus and evaluation the quality of Evodiae fructus sold in markets. Methods: Open column chromatography was used to separate and purify rutaecarpine and evodiamine, the two major alkaloids from Evodiae fructus extract as a laboratory standard. Chromatographic separation was achieved using a Germini C18 column (150 mm × 4.6 mm I.D., 5 µm), detected at 210 nm. The mobile phase consisted of acetonitrile (A), methanol (B), and water (C). The validated method simultaneously determined alkaloid content in 40 batches of samples collected from markets in different regions of Vietnam. Results: In one-step purification, our method yielded 326 mg of rutaecarpine and 128 mg of evodiamine from 3.2 g of crude extract, with purities of 98.9 and 98.5%, respectively. The structures of these compounds were identified using 1H NMR and 13C NMR. There was a significant correlation between alkaloid content and fruit size, with a Spearman correlation coefficient of>0.5 (p

Owing to its high theoretical capacity (3860 mAh/g, over 10 times that of graphite) and its lowest theoretical electrochemical potential (-3.04 V vs SHE), Li metal is an ideal anode material for improving the capacity of rechargeable Li batteries [1]. However, the practical application of the Li anode is severely hindered by its high reactivity with standard electrolyte compositions, which results in limited Coulombic efficiency (CE) in those electrolytes (for instance, 85-90% with 1 M LiPF6 EC:DEC [2]). Strategies to improve CE have focused on electrolyte engineering, including development of highly concentrated electrolytes (HCE) and more recently, local high-concentration electrolytes (LHCE) [3]. A feature shared by these strategies is the promotion of contact-ion pairing, which enhances anion contributions to the solid electrolyte interphase (SEI). Among the best-performing salts are fluorinated lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and lithium bis(fluorosulfonyl)imide (LiFSI), which are believed to promote stable inorganic-rich SEIs and correlate with higher CE [4]. A second strategy of interest is to pursue development of additives incorporated at relatively low concentrations (e.g., 2-5 wt%) that can favorably alter the SEI, such as carbonates (e.g., vinylene carbonate (VC) [5] and fluoroethylene carbonate (FEC) [6]), sulfates (e.g., ethylene sulfate (DTD) and 1,3-propanesulfonate (PS) [7]), and borates (e.g., lithium difluoro(oxoalate) borate (LiDFOB) [8] and tris (2,2,2-trifluoroethyl) borate (TTFEB) [9]). An advantage of this strategy is the possibility to ultimately lower reliance on high fluorinated salt concentrations, which are costly and can be corrosive towards the Al current collector, and potentially expand the versatility of available electrolyte frameworks having competitive CE. However, compared to the principles developed for salt and solvent selection in HCE and LHCE, the mechanism behind successful additive activation needs elucidation. In this work, we examined the potential of "FSI-like," neutral sulfonyl/sulfamoyl fluorides (R-SO2F and R-R’-NSO2F, Figure 1) as functional additives for Li cycling, motivated by their structural similarity to the high-performance FSI- anion. The examined baseline electrolytes include high-CE systems consisting of LiFSI dissolved in various solvents: fluoroethylene carbonate (FEC, 1 and 4 M salt), 1,2-dimethoxyethane (DME, 4 M), and dimethyl carbonate (DMC, 6 M). The ability for each additive to coordinate with Li+ was first examined by NMR, with trends rationalized in part by supporting microcalorimetry data on the degree of solvent coordination strength. We relate these to CE and cycling outcomes in each electrolyte. Interestingly, we find that additives have negligible effect on CE in FEC-based electrolytes, whereas significant impacts were observed in DME and DMC. We relate these diverse outcomes to the SEI chemical compositions and gases evolved during galvanostatic cycling, as characterized by X-ray photoelectron spectroscopy (XPS) and gas chromatography (GC), which help to rationalize competitive reactions among solvent, anion, and additive. Unfortunately, additives had a negative-to-neutral impact on CE in these systems. Thus, we finally examined a LiPF6 in carbonate electrolyte, 1 M LiPF6 in EC/DMC (LP40), where we hypothesized that competitive reduction of coordinating additives over problematic carbonate solvent would lead to performance gains. Indeed, significant improvements (up to 94%, compared to baseline 89% over the initial 50 cycles) in CE were observed for two additives, with their structural advantages further discussed. Overall, our findings provide insights into the effects of sulfonyl/sulfamoyl fluoride additive structures on Li metal cyclability and the compositions of baseline electrolytes whose electrochemical cycling stability can be effectively modulated by these additives. Xu, W., et al., Lithium metal anodes for rechargeable batteries. Energy & Environmental Science, 2014.7(2):p.513-537. Genovese, M., et al., Combinatorial methods for improving lithium metal cycling efficiency. Journal of The Electrochemical Society, 2018.165(13):p.A3000. Hobold, G.M., et al., Moving beyond 99.9% Coulombic efficiency for lithium anodes in liquid electrolytes. Nature Energy, 2021.6(10):p.951-960. Suo, L., et al., Fluorine-donating electrolytes enable highly reversible 5-V-class Li metal batteries. Proceedings of the National Academy of Sciences, 2018.115(6):p.1156-1161. Aurbach, D., et al., On the use of vinylene carbonate (VC) as an additive to electrolyte solutions for Li-ion batteries. Electrochimica acta, 2002.47(9):p.1423-1439. Markevich, E., et al., Fluoroethylene carbonate as an important component in electrolyte solutions for high-voltage lithium batteries: role of surface chemistry on the cathode. Langmuir, 2014.30(25):p.7414-7424. Han, B., et al., Poor Stability of Li2CO3 in the Solid Electrolyte Interphase of a Lithium ‐Metal Anode Revealed by Cryo ‐Electron Microscopy. Advanced Materials, 2021.33(22):p.2100404. Liu, J., et al., Lithium difluoro (oxalato) borate as a functional additive for lithium-ion batteries. Electrochemistry communications, 2007.9(3):p.475-479. Ma, Y., et al., Enabling reliable lithium metal batteries by a bifunctional anionic electrolyte additive. Energy Storage Materials, 2018.11:p.197-204. Figure 1. (a) Sulfonyl/sulfamoyl fluoride chemical structures and (b) R-S and S-F bond lengths calculated by density functional theory. Figure 1

It has been widely suggested in literature that a lithium fluoride (LiF)-rich solid electrolyte interphase (SEI) affects Coulombic efficiency (CE) of the Li metal anode used with liquid electrolytes. Yet, the influence of LiF on Li metal deposition has been challenging to examine. Herein, we developed a method to synthesize LiF nanoscale particles with tunable sizes (30–300 nm) on Cu electrodes by electrochemical reduction of fluorinated gases under controlled discharge rates and capacities. The impact of LiF nanoparticles on overpotential and morphology of Li deposition was further studied in a conventional carbonate electrolyte. By cyclic voltammetry, Li plating overpotentials exhibit a clear correlation with the total surface area of LiF particles. Additionally, Li metal deposits (10 μAh cm−2) nucleated under galvanostatic conditions (0.5 mA cm−2) on Cu/LiF showed increasing feature sizes with a lower average LiF particle size and higher coverage of LiF. However, no significant improvement in CE was observed for LiF-coated Cu. Our findings provide evidence that a particle-based mode of SEI fluorination can influence early-stage Li nucleation to a modest degree, and this effect is maximized when LiF is uniformly and densely distributed. However, sparser and larger LiF have vanishing or even detrimental effect on cycling performance.

Alkaloids are distributed in plant kingdom and play important role in protection, germination as well as plant growth stimulants. Most of them are chiral compounds and are clinically administered as the racemic mixture, even though its enantiomers have been known to exert different pharmacological activity. Liquid chromatography using chiral stationary phases (CSP) proved to be an essential tool with a wide range of applications, including analysis of the stereochemistry of natural compounds. This review gives an overview of chiral separation alkaloids that were used in theoretical studies and/or applications in recent years. It shows the possibilities of polysaccharide CSPs have now also been established as the first-choice of chiral phases for enantiomer separation.

The V4P7 phase is synthesized by a facile high energy mechanical milling (HEMM) using vanadium (V) and red phosphorus (P), and its electrochemical properties and reaction mechanism as an anode for lithium ion batteries (LIBs) are investigated. As-synthesized 100 nm-sized V4P7 nanopowder electrode shows the insertion reaction during lithiation/delithiation by forming the amorphous Li-V-P ternary phase and delivers the high discharge and charge capacities of 1035 and 882 mA h g-1, respectively, with a high Coulombic efficiency of 85% at the current density of 100 mA g−1. In addition, V4P7 nanopowder is encapsulated with the conformal carbon layer, which is achieved through polymerization of dopamine and subsequent carbonization. As-fabricated core-shell V4P7@C nanocomposite electrode exhibits the much improved high rate capability and long cycle stability, delivering a high capacity of 388 mA h g-1 after 200 cycles at a high current density of 1 A g−1, which is attributed to high electrical conductivity, high Li+ ion mobility, and structural stability to restrict the aggregation and pulverization of active materials.

In attempt to contribute in official monographs of Korean Pharmacopoeia, an HPLC method was developed and fully validated for the determination of tolperisone hydrochloride in tablets which have never been published in other forgein Pharmacopoeia. Analysis was carried out in an ODS column (250 × 4.6 mm I.D., 5 μm) with common solvents include acetonitrile and ammonium hydrophosphate buffer as mobile phase. The assay was validated according to International Conference on Harmonization (ICH) guidelines. The method has good linearity in the range of 5 – 200 μg/mL tolperisone. Intra-day precision varied between 0.04 and 0.10 %. Relative standard deviations of inter-day precision ranged between 0.43 and 1.24 % for peak area. The percentage recovery of the tolperisone ranged between 99.8 and 101.2 % in material. Recoveries in tablets were ranged between 98.7 and 100.8 %, thus confirmed the suitability of method for estimation of tolperisone hydrochloride in tablet dosage form.

A method was developed and fully validated for the determination of terbutaline, a β 2 -receptor agonist, in human plasma. Plasma samples were prepared by solid-phase extraction with Sep-Pak silica, followed by high-performance liquid chromatography (HPLC). The terbutaline was pre-separated from the interfering components in plasma on a Luna C18 (2) column, and terbutaline and salbutamol as an internal standard were resolved and determined on a Luna Silica column. The two columns were connected by a switching valve equipped with silica pre-column. The pre-column was used to concentrate the terbutaline in the eluent from the C18 column before back-flushing onto the silica column with fluorescence detection at an excitation/emission wavelength of 276/306 nm. The method was shown to be specific by testing six different human plasma sources. Linearity was established for a concentration range of 0.4-20.0 ng/mL with a correlation coefficient of 0.9999. The lower limit of quantitation was 0.4 ng/mL with a precision of 10.1% as C.V.%.

Capillary zone electrophoresis was successfully applied to the enantiomeric purity determination of dexlansoprazole using sulfobutyl ether-β-cyclodextrin and methyl-β-cyclodextrin as chiral selectors. Separations were carried out in a 50 μm, 64/56 cm fused-silica capillary. The optimized conditions included 90 mM phosphate buffer, pH 6.0, containing 30 mM sulfobutyl ether-β-cyclodextrin, 20 mM methyl-β-cyclodextrin as background electrolyte, an applied voltage of 25 kV and a temperature of 16 °C, detection was at 280 nm. The assay was validated for the S-(−)-lansoprazole in the range of 0.2–1.0%. The limit of detection was 0.07%, the limit of quantitation was 0.20%, relative to a total concentration of 4.0 mg mL−1. Intra-day precision varied between 1.72 and 2.07%. Relative standard deviations of inter-day precision ranged between 1.62 and 1.96% for peak area ratio. The assay was applied for the determination of the chiral purity of dexlansoprazole capsules. Recovery in capsules was ranged between 101.7 and 103.1%.

Currently nonaqueous titration method for the assay method using the hazardous reagent, mercuryacetate for difemerine hydrochloride has been used in Korean Pharmaceutical Codex. We developed analternative titration assay method by substituting the use of the hazardous reagent, mercury acetate to the useof less toxic ones like ethyl alcohol. The linearity of the calibration curves in the desired concentration rangewas good (r>0.999). Precision was less than 0.64%. Accuracy was obtained with recoveries in range of 99.10%and 99.71%. The developed assay could be expected to become valuable tools for revising the KoreanPharmaceutical Codex.요약: 국가 공정서 중 하나인 대한민국약전외의약품 기준에는 디페메린염산염의 정량법으로 유해시약인 아세트산수은을 사용하는 비수적정법이 수재되어 있다. 본 연구에서는 디페메린염산염의 환경 친화적인 대체 시험법으로 보다 안전하고 효율적인 친환경용매인 에탄올을 사용하는 중화적정법을 개발하고,분석법을 검증하였다. 디페메린염산염의 직선성은 상관계수(r)가 0.999 이상을 나타내었고, 정확도는99.10~99.71%, 정밀도는 0.64% 이하로 나타났다. 개발된 시험법은 대한민국약전외의약품 기준의 개정에기여가 될 것이다.Key words: Korean Pharmaceutical Codex, hazardous reagents, alternative testing methods, validation, titration

A specific and sensitive liquid chromatography-electrospray ionization tandem mass spectrometry method (LC-ESI- MS/MS) was developed and validated for the simultaneous quantification of porphyrins (coproporphyrin, pentacarboxylporphy- rin, hexacarboxylporphyrin, heptacarboxylporphyrin, and uroporphyrin) in human plasma and urine. Acidified plasma samples and urine samples were prepared by using liquid-liquid extraction using ethyl acetate and protein precipitation with acetonitrile, respectively. The separation was achieved onto a Synergi Fusion RP column (150 mm × 2.0 mm, 4 µm) with a gradient elution of mobile phase A (0.1% formic acid in 2 mmol/L ammonium acetate, v/v) and mobile phase B (20% methanol in acetonitrile, v/ v) at a flow rate of 450 µL/min. Porphyrins and the internal standard (IS), coproporphyrin I- 15 N4, were detected by a tandem mass spectrometer equipped with an electrospray ion source operating in positive ion mode. Multiple reaction monitoring (MRM) transitions of the protonated precursor ions and the related product ions were optimized to increase selectivity and sensi- tivity. The proposed method was validated by assessing selectivity, linearity, limit of quantification (LOQ), precision, accuracy, recovery, and stability. The calibration curves were obtained in the range of 0.1-100 nmol/L and the LOQs were estimated as 0.1 nmol/L for all porphyrins. Results obtained from the validation study of porphyrins showed good accuracy, precision, recov- ery, and stability. Finally, the proposed method was successfully applied to clinical studies on the autism spectrum disorder (ASD) diagnosis of 203 Korean children.

Currently oxidation-reduction titration method for the assay method using the hazardous reagent, carbon tetrachloride, for cefroxadine capsules has been used in Korean Pharmaceutical Codex. We developed and validated an alternative HPLC assay method by substituting the use of the hazardous reagent, carbon tetrachloride, to the use of less toxic ones like acetonitrile. The linearity of the calibration curves in the desired concentration range was good (r > 0.999). Relative standard deviations of intra-day precision were ranged between 0.30% and 0.69% and inter-day precision were ranged between 0.47% and 0.82%. Accuracy was obtained with recoveries in range of 100.20% and 100.56%. Developed method was applied to the determination of cefroxadine in commercial cefroxadine capsule and could be expected to become valuable tools for revising the Korean Pharmaceutical Codex. 요 약: 국가공정서 중 하나인 대한민국약전외의약품기준에는 세프록사딘 캡슐의 정량법으로 유해시약 인 사염화탄소를 사용하는 산화환원분석법이 수재되어 있다. 세프록사딘 캡슐의 환경 친화적인 대체 시 험법으로 보다 안전하고 효율적인 친환경용매를 사용하는 HPLC 분석법을 개발하고, 이를 검증하였다. 직선성은 상관계수(r)가 0.999이상으로 우수하였다. 일내 정밀도는 상대표준편차 0.30~0.69%, 일간 정밀 도는 0.47~0.82%로, 회수율은 100.20~100.56%로 나타났다. 개발한 시험법을 이용하여 시중 유통 중인 세 프록사딘 캡슐 중 세프록사딘의 함량측정에 응용하였다. 개발된 시험법은 대한민국약전외의약품기준의 개정에 기여가 될 것이다.

The aim of this study was to investigate the inhibitory effects of rutaecarpine on DNA strand breaks and apoptosis induced by hydrogen peroxide (H2O2) in murine Hepa-1c1c7 cells. Oxidative DNA damage was estimated by nuclear condensation assessment, fluorescence-activated cell sorting analysis, and Comet assay. Rutaecarpine inhibited cell death induced by 500 μM H2O2, as assessed by 4',6-diamidino-2-phenylindole (DAPI) staining. Treatment with rutaecarpine reduced the number of DNA strand breaks induced by H2O2, as assessed by DAPI staining and Comet assay, and increased quinone reductase, phosphatidylinositol 3-kinase, and pAkt protein levels, as assessed by western blotting.

Line sleeves, which used to connect ACSR cables when transmission lines were constructing, sometimes cause power transmission failure due to deterioration and corrosion. Therefore, power transmission line should be inspected regularly to prevent national disaster. Current inspection tool detects insertion length of transmission line on line sleeves, the inspection tool includes enormous error by operator. Moreover, the system is not controlled remotely, negligent accident would be caused while inspecting. To deal with those problems, KEPCO reviewed several ways to inspect line sleeves and proposes new method to inspect line sleeve by measuring magnetic flex which penetrate junction of steel and aluminum sleeve. The developed inspection tool is reliable enough to detect eccentric sleeves. Also, the developed inspection device was applied on actual transmission line and verified its effectiveness.

We examined the effects of essential oil from Thujopsis dolobrata Sieb. et Zucc. var. hondai Makino (EOTD) (Cupressaceae) on atopic dermatitis (AD)-like skin lesions in NC/Nga mice. Treatment with EOTD twice daily for two weeks ameliorate AD-like skin lesions induced by DNCB (2,4 dinitrochlorobenzene), and clinical scores were reduced to 7.29, 7.07, and 4.5 points in the groups treated with 1.5%, 3.0%, and 6.0% extract (p

Free radical scavenging and antioxidants have attracted attention as a way to prevent the progression of Parkinson`s disease (PD). This study was carried out to investigate the effects of n-hexane fraction from Laurus nobilis L. (Lauraceae) leaves (HFL) on dopamine (DA)-induced intracellular reactive oxygen species (ROS) production and apoptosis in human neuroblastoma SH-SY5Y cells. Compared with apomorphine (APO, IC50=18.1 uM) as a positive control, the HFL IC50 value for DA-induced apoptosis was 3.0 ug/ml, and two major compounds from HFL, costunolide and dehydrocostus lactone, were 7.3 uM and 3.6 uM, respectively. HFL and these major compounds significantly inhibited ROS generation in DA-induced SH-SY5Y cells. A rodent 6-hydroxydopamine (6-OHDA) model of PD was employed to investigate the potential neuroprotective effects of HFL in vivo. 6-OHDA was injected into the substantia nigra of young adult rats and an immunohistochemical analysis was conducted to quantitate the tyrosine hydroxylase (TH)-positive neurons. HFL significantly inhibited 6-OHDA-induced TH-positive cell loss in the substantia nigra and also reduced DA induced a-synuclein (SYN) formation in SH-SY5Y cells. These results indicate that HFL may have neuroprotective effects against DA-induced in vitro and in vivo models of PD.

This study was conducted to investigate the ratios of phosphorus release to COD uptake, phosphorus release to nitrate removal, and phosphorus uptake to phosphorus release by DNPAOs(denitrifying phosphate accumulating organisms). In case , influent 1 were fed with synthetic wastewater with influent 2 injection to anoxic zone and the case V were fed with municipal wastewater with side stream oxic zone instead of influent 2 injection. As a result, the ratio of phosphorus release to carbon uptake was increased in accordance with nitrate supply. The DNPAOs simultaneously took up phosphate and removed nitrate from the anoxic reactor. In case , with above 20 mg/L of sufficient supply, phosphate was taken up excessively by the DNPAOs in anoxic condition. The large amount of both uptake and release of phosphorus occurred above 20 mg/L of nitrate supply, achieving the ratio of phosphorus uptake to phosphorus release to be 1.05. In case V, phosphate luxury uptake was not occurred in system due to 6.98 mg/L of insufficient supply and the ratio of phosphorus uptake to phosphorus release was 0.98. Consequently, if nitrate as the electron acceptor was sufficient in anoxic zone, the ratio was found to be high.

The analysis of prestressed box-girder bridges using the spline finite strip method is presented. In the present study, the spline finite strip method is modified by using the non-periodic B-spline interpolation. In the analysis of the prestressed box-girder bridges, the short-term losses of prestressing are considered and each tendon force at the tendon point is evaluated by summation of the adjacent segment forces. Once the equivalent forces acting on the structure at the tendon points are found, they are transformed into statically equivalent forces at the adjacent node of nodal line. Several examples were analyzed to verify the performance of present method. Good agreements were obtained when compared with the previous studies.

Several isolated compounds from the wood part of Thujopsis dolabrata were evaluated for their inhibitory effects against antigen-induced mast cell degranulation and interleukin-4 (IL-4) secretion, as well as IL-4 mRNA and protein expression in immunoglobulin E (IgE)-sensitized RBL-2H3 cells. Among the five isolated compounds, (-)-elema-1,3,11(13)-trien-12-ol (1) and thujopsene (2) exhibited the potent inhibitory activity against mast cell degranulation measured by β-hexosaminidase release with IC values of 27.4 µM and 25.1 µM, respectively. These compounds also inhibited the release of IL-4 (IC values of 7.0, 6.7 µM, respectively), IL-4 mRNA expression (IC values of 16.5, 7.2 µM, respectively) and IL-4 protein expression (IC values of 17.0, 9.6 µM, respectively) in antigen-induced IgE-sensitized RBL-2H3 cells. These results suggested that (-)-elema-1,3,11(13)-trien-12-ol (1) and thujopsene (2) effectively inhibits mast cell degranulation as well as IL-4 production, suggesting that these compounds from Thujopsis dolabrata can be used as candidates for IgE-mediated allergic disorders.

During the last decades, rare-earth (RE) ion-doped phosphors have received much attention due to their high luminescent properties. For this reason, many studies have been focused on new composition of phosphor with high luminescent properties. Eu3+ doped SrLu2O4, which is a new composition phosphor, has been reported to describe the luminescent properties. Upon excitation with ultraviolet (UV) regions, Eu3+ doped SrLu2O4 phosphor exhibited narrow red emissions due to the 4f-4f transition of Eu3+ ions. Eu3+ ions only can be excited with UV regions and the property of narrow red emission has a limitation to apply for lighting devices such as white light-emitting diodes (WLEDs) due to a low color rendering index (CRI). In this study, we synthesize the Eu2+ doped SrLu2O4 red phosphors with solid-state reaction and characterize the luminescent properties for the first time. For the synthesis of SrLu2O4 at stoichiometric condition, it is hard to synthesize the pure SrLu2O4 phase, because formation of a second phase Lu2O3 were consistently unable to avoid. The pure phase of SrLu2O4 was formed at certain ratio of starting materials and annealing temperature conditions. The mixtures were annealed at various temperatures (1400–1600 °C) for 3 hours under 5% H2/N2 atmosphere in order to reduce Eu3+ to Eu2+. Upon excitation with 450 nm, the synthesized SrLu2O4:Eu2+ phosphors exhibited a strong red emission centered at 610 nm due to the 4f-5d transition of Eu2+ ions (Figure 1). SrLu2O4:Eu2+ phosphors showed highest PL intensity at very low europium doping level, which intensity value was 85% of commercial (Sr,Ca)AlSiN3:Eu2+ (SCASN). In addition, SrLu2O4:Eu2+ phosphors also showed a strong thermal quenching property, which indicated that PL intensity measured at 200 oC was reduced to almost zero per cent of the initial value (25 oC). These high value of PL intensity and strong thermal quenching property can be used as a high potential optical temperature sensor application. Figure 1

The purpose of this study was to determine whether the Laurus nobilis chloroform fraction (LNCF) protects against cerebral ischemia neuronal damage. Human neuroblastoma SH-SY5Y cells and brain slices from rats were subjected to oxygen and glucose deprivation (OGD), followed by reoxgenation with and without LNCF. The viabilities of SH-SY5Y cells and brain slices from the rats were 58.5±4.9% and 79.7±5.9% in the group subjected to OGD, and 80.4±0.4% and 97.2±1.9% at 4 µg/ml of LNCF, respectively. LNCF also significantly inhibited death-associated protein kinase (DAPK) dephosphorylation. Pretreatment with LNCF at 4 mg/kg significantly decreased infarct size by 79% of vehicle control in the middle cerebral artery occlusion (MCAO) in vivo model. LNCF is a neuroprotective drug candidate against cerebral ischemia neuronal damage.

Background: Diagnosis of subpulmonary effusion is thought to be somewhat difficult more than pulmonary effusion. Clinical course and pathophysiology are thought to be different from typical pulmonary effusion. This study was done for increasing high suspicious index and early diagnosis of subpulmonary effusion. Method: Among the patients at dept. of chest medicine, National Medical Center from January 1990 to Dec. 1993, 232 cases of typical pulmonary effusion and 42 cases of subpulmonary effusion were studied. Result: 1) The ratio of subpulmonary effusion and typical pulmonary effusion was about 1:5. 2) Male to Female ratio was 1:1 in both effusion. 3) Rt. side pleural and subpleural effusion were slightly predominant. 4) Subjective symptoms are chest pain, cough and exertional dyspnea. There is no difference between subpulmonary and typical pulmonary effusion. 5) Duration of symptom was slightly longer in subpulmonary effusion. 6) The most common cases of pleural effusion is tuberculosis in both subpulmonary & typical pulmonary effusion. Non-specific pleuritis was more common in subpulmonary effusion. 7) Pleural effusion was recurred about one fifth in both subpulmonary & pulmonary effusion. Conclusion: We studied clinical course and laboratory findings between subpulmonary & pulmonary effusion. However there are no definite difference between subpulmonary & pulmonary effusion. Duration of symptom was slightly longer in subpulmonary effusion. Most common cause was tuberculosis. Non specific pleuritis was more prevalent in subpulmonary effusion.

Background: Recently there has been a trend of an increasing incidence of mediastinal tuberculous lymphadenitis(MTL) in adults. MTL often cause bronchial stenosis or esophago-mediastinal fistula. In spite of effective treatment, it is difficult to cure. Moreover, relapse frequently occurs. Authors analyzed chest CT findings and clinical features of 29 cases with MTL Methods: 29 cases with MTL were retrospectively studied with the clinical and radiologic features from April 1990 to March 1995 Results: 1) A total of 29 cases were studied. 12 cases were male and 17 cases were female. The male to female ratio was 1:1.4 Mean age was 29 years old. The 3rd decade(45%) was the most prevalent age group 2) The most common presenting symptoms and signs were palpable neck masses(62%) followed by cough(59%) and sputum(38%) 3) Except in one case of MTL, all patients had coexisting pulmonary tuberculosis, cervical tuberculous lymphadenitis, endobronchial tuberculosis and tuberculous pleurisy. Among the coexisting tuberculous diseases, Pulmonary tuberculosis was the most common(76%) 4) On simple chest X-ray, mediastinal enlargement was noted in 21 cases(72%), but it was not noted in 8 cases(28%). The most frequently involving site was the paratracheal node in 16 cases(72%). Rt side predominence(73%) was noted 5) Patterns of node appearance on a postcontrast CT scan were classified into 3 types. There were 19 cases(30%) of the Homogenous type, 30 cases(47%) of the Central low density type and 15 cases(23%) of the Peripheral fat obliteration type. The most common type was the central low density type. The most common lymph node size was 1~2 cm(88%) 6) The most frequently involved site was the paratracheal node in 26 cases(89%) by chest CT. Rt side(63%) was predominant 7) 9 cases(43%) had complete therapy and most common treatment duration was 13 - 18 months. 12 cases(57%) had incomplete continuing antituberculous medication and half of the cases had been treated above 19 months. Conclusion: Chest CT findings of MTL showed central low density area and peripheral rim enhancement, so this characteristic findings could differentiate it from other mediastinal diseases and help a diagnosis of tuberculosis. In spite of effective antituberculous medication, it is difficult to cure. Moreover, relapse frequently occurs. Further studies will be needed of the clinical features and the treatment of MTL.

A 41-year-old female was admitted to our hospital for self-audible wheezing sound and dyspnea. On past history, she has been suffered from chest discomfort, and treated recurrently by other hospitals. But, there was no symptomatic improvement. A stridor and mixed wheezing sound was auscultated on whole lung field. PFT revealed fixed type or variable intra- & extra-thoracic air way obstructive pattern. By bronchoscopy & bronchogram, we found web-like structure on the distal trachea. A bronchoplasty was performed and the post-operative PFT showed slight improvement & she had no more complaints.