• Clean Technology
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• v.22 no.4
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• pp.308-315
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• 2016

$SiO_x/ZnO$ composites were prepared from sol-gel method for excellent cycle life characteristics. The composites were coated by PVC as a carbon precursor. ZnO removal to create a void space therein was able to buffer the volume change during charge and discharge. To determine the crystal structure and the shape of the synthesized composite, XRD, SEM, TEM analysis was performed. The carbon contents in the composites were confirmed by TGA. The pore structure and pore size distribution of the composite was measured with the BET specific surface area analysis and BJH pore size distribution. Enhanced electric conductivity by carbon addition was determined from powder resistance measurement. Electrochemical properties were measured with the AC impedance and the charge and discharge cycle life characteristics. When carbon was coated on the $SiO_x/ZnO$ sample, the electrical conductivity and the discharge capacity were increased. After removal of ZnO with HCl the surface area of the sample was increased, but the discharge capacity was decreased. $SiO_x/ZnO$ sample without acarbon coating showed very low discharge capacity, and after carbon coating the sample showed high discharge capacity. For cycle life characteristics, $C-SiO_x/ZnO$ composite (Zn : Si : C = 1 : 1 : 8) with a capacity of $815mAh\;g^{-1}$ at 50 cycle and 0.2 C has higher capacity than existing graphite-based anode materials.

• Clean Technology
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• v.24 no.1
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• pp.9-14
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• 2018

In this study, Material life cycle evaluation was performed to analyze the environmental impact characteristics of TiN-Zr membrane manufacturing process. The software of MLCA was Gabi. Through this, environmental impact assessment was performed for each process. Transition metal nitrides have been researched extensively because of their properties. Among these, TiN has the most attention. TiN is a ceramic materials which possess the good combination of physical and chemical properties, such as high melting point, high hardness, and relatively low specific gravity, high wear resistance and high corrosion resistance. With these properties, TiN plays an important role in functional materials for application in separation hydrogen from fossil fuel. Precursor TiN was synthesized by sol-gel method and zirconium was coated by ball mill method. The metallurgical, physical and thermodynamic characteristics of the membranes were analyzed by using Scanning Electron Microscope (SEM), Energy Dispersive X-ray (EDS), X-ray Diffraction (XRD), Thermo Gravimetry/Differential Thermal Analysis (TG/DTA), Brunauer, Emmett, Teller (BET) and Gas Chromatograph System (GP). As a result of characterization and normalization, environmental impacts were 94% in MAETP (Marine Aquatic Ecotoxicity), 2% FAETP (Freshwater Aquatic Ecotoxicity), 2% HTP (Human Toxicity Potential). TiN fabrication process appears to have a direct or indirect impact on the human body. It is believed that the greatest impact that HTP can have on human is the carcinogenic properties. This shows that electricity use has a great influence on ecosystem impact. TiN-Zr was analyzed in Eco-Indicator '99 (EI99) and CML 2001 methodology.

• Bulletin of the Korean Chemical Society
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• v.24 no.11
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• pp.1659-1663
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• 2003

$Al_2O_3$ thin films were grown on H-terminated Si(001) substrates using dimethylaluminum isopropoxide [DMAl: $(CH_3)_2AlOCH(CH_3)_2$], as a new Al precursor, and water by atomic layer deposition (ALD). The selflimiting ALD process by alternate surface reactions of DMAI and $H_2O$ was confirmed from measured thicknesses of the aluminum oxide films as functions of the DMAI pulse time and the number of DMAI-$H_2O$ cycles. Under optimal reaction conditions, a growth rate of ~1.06 ${\AA}$ per ALD cycle was achieved at the substrate temperature of $150\;^{\circ}C$. From a mass spectrometric study of the DMAI-$D_2O$ ALD process, it was determined that the overall binary reaction for the deposition of $Al_2O_3\;[2\;(CH_3)_2AlOCH(CH_3)_2\;+\;3\;H_2O\;{\rightarrow}\;Al_2O_3\;+\;4\;CH_4\;+\;2\;HOCH(CH_3)_2]$can be separated into the following two half-reactions: where the asterisks designate the surface species. Growth of stoichiometric $Al_2O_3$ thin films with carbon incorporation less than 1.5 atomic % was confirmed by depth profiling Auger electron spectroscopy. Atomic force microscopy images show atomically flat and uniform surfaces. X-ray photoelectron spectroscopy and cross-sectional high resolution transmission electron microscopy of an $Al_2O_3$ film indicate that there is no distinguishable interfacial Si oxide layer except that a very thin layer of aluminum silicate may have been formed between the $Al_2O_3$ film and the Si substrate. C-V measurements of an $Al_2O_3$ film showed capacitance values comparable to previously reported values.

• Polymer(Korea)
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• v.36 no.4
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• pp.531-535
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• 2012

Conductive polyaniline (PANI) nanofibers in UV-curable resin were used for a transparent conductive film. The emeraldine-salt PANI (ES-PANI) nanofibers were prepared by chemical oxidation polymerization of aniline, which could be changed into emeraldine-base PANI by dedoping. EB-PANI nanofibers as a precursor for conductive fillers were thereby transformed into re-dpoed PANI (rES-PANI) by dodecylbenzenesulfonic acid in the UV-curable resin solution. rES-PANI nanofibers have high conductivity and long-term stability in the solution without a defect of nanostructure. The resulting conductive resin solution was proved to be highly stable where no precipitation of rES-PANI fillers was observed over a period of 3 months. The transparent film was spin-casted on a poly(methyl methacrylate) sheet of thickness ca. $5{\mu}m$. A surface resistance of $6.5{\times}10^8{\Omega}/sq$ and transmittance at 550 nm of 91.1% were obtained for the film prepared with a concentration of 1.4 wt% rES-PANI nanofibers in the solution. This transformation process of rES-PANI from ES-PANI by dedoping-redoping can be an alternative method for the preparation of an antistatic protection film with controllable surface resistance and optical transparencies with the PANI concentration in UV-curable solution.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.1-10
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• 1988

Previously. we reported that the intraperitoneal administration of ginseng crude saponin increased: (I) nuclear RNA polymerase activity. (2) nuclear RNA synthesis. (3) cytoplasmic RNA synthesis. (4) cytoplasmic heavy polyrioosome content. (5) amino acid incorporation in vitro of microsome and polysome isolated rat liver. and (6) the incorporation rate of labeled amino acids into serum protein. In addition, a spectacular increase in the rough endoplasmic reticulum of hepatocyte administered crude saponin for four weeks orally was shown through electron microscopy. An increase in polysomal content in membrane-hound ribosome was shown through ultracentrifugation. Recently, successive intraperitoneal. administration .of $ginsenosid-Rb_2$ was given to streptozotocin (STZ) diaoetic rats of hypoproteinemia. The blood urea nitrogen and hepatic urea concentration were decreased significantly. The total protein and alhumin levels in the serum were increased in comparison to control values. In contrast. the $ginsenoside-Rb_2$ treated group of STZ diahetic rats showed a significant increase in liver RNA. total ribosome and membrane-bound ribosomal contents. The administration of $ginsenoside-Rb_2$ increased the incorporation rate of labeled - precursor into total serum protein. Additionally $ginsenoside-Rb_2$ improved the nitrogen balance of diabetic rats. On the bases of these experimental results, ginseng saponin has a metabolic stimulatory or anabolic action on RNA and protein synthesis.

• The Korean Journal of Zoology
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• v.14 no.4
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• pp.199-204
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• 1971

The effect of 400 R total-body X-irradiation on the rate of deoxycytidine-2-$^14 C$(CdR-2-$^14 C$) into DNA and on the degradation of DNA has been studied in the liver, spleen and thymus of the rat. The postirradiation period can be divided into a radiation reaction period followed by a regeneration period. During the period of radiation reaction, which consists of days 1-2, markdely decreased CdR-2-$^14 C$ incorporation into DNA of each organ is observed. Rate of incorporation of labeled precursor in the thymus shows the most profound decrease, whereas those in the liver and spleen show similar decrease when expressed as percent of normal. The change in the amount of DNA as percent of normal exhibits a similar pattern in all organs, but the rate of decrease is larger in the spleen and thymus compared to that in the liver. The period of regeneration as judged by the incorporation experiment appears day 4 to 5, which consists of the second phase of the regeneration period. The second phase is highlighted by a markedly increased rate of CdR-2-$^14 C$ incorporation and by a slow and continued increase in the amount of DNA in all organs. The regeneration occurs faster in the liver and spleen than in the thymus which is the most radiosensitive of the all. The findings of the present experiments are strongly suggestive of the fact that the radiation-induced loss of spleen and thymus DNA as well as the radiation-caused inhibition in the CdR incorporation into DNA of the thymus are the important factors in the elevated levels of CdR in the urine and plasma.

• The Korean Journal of Zoology
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• v.15 no.1
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• pp.1-14
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• 1972

The effect of 400 R of whole-body X-irradiation on DNA synthesis, DNA degradation, CdR-aminohydrolase activity and oxygen uptake in the liver, spleen and thymus of the rat has been studied in connection with the radiosensitivity of these tissues. The rate of CdR-2-$^14 C$ incorporation has been followed during the postirradiation period and has been correlated with the increased levels of CdR-aminohydrolase activity druing this period. The postirradiation period comprises radiation reaction and tissue regeneration periods. During the period of radiation reaction, markedly decreased precursor incorporation, decreased tissue levels of DNA and decreased uptake of oxygen are noted as well as an increase in the CdR-aminohydrolase activity. The period of regeneration appears to consist in two discrete phases. The first phase reveals a return of CdR-aminohydrolase activity and the second phase is highlighted by a markedly increased rate of labeled CdR incorporation. Various events occurring during the radiation reaction period and the regeneration period in the three tissues studied can be considered qualitatively the same, differing only in the degree of acute cell death, in the duration of the delay of DNA synthesis in the sruviving cells, and in the rate of recovery resulting from accelerated cell replication during the period of regeneration. A possible biochemical mechanism involved in the DNA synthesis and degradation, in connection with the inreased levels of CdR-aminohydrolase after irradiation, has been briefly discussed.

• Journal of the Korean Vacuum Society
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• v.18 no.1
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• pp.15-23
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• 2009

Saturation-coverage silyl, $-SiH_3(a)$, overlayers were prepared from $Si_2H_6$ adsorption on three comparative surfaces: clean unmodified; D-precovered; and atomically roughened Si(100). Together with its precursor-mediated adsorption behavior, the surface reactivity of $Si_2H_6$ was found to be the highest on the unmodified Si(100)-$2{\times}1$ surface. This was correlated with its dissociative adsorption mechanism, in which both the $H_3Si-SiH_3$ bond scission and the dual surface $Si-SiH_3(a)$ bond formation require a surface dangling bond 'pair'. The unusually high thermal stability of $-SiH_3(a)$ on the unmodified surface was ascribed to a nearly close-packed $-SiH_3(a)$ coverage of ${\sim}0.9$ monolayer and the consequent lack of dangling bonds on the silyl-packed surface.

• Food Science and Preservation
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• v.10 no.2
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• pp.158-161
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• 2003

The six-year old fresh ginseng harvested at earlier October was stored for 10 weeks in the rendition of 4$^{\circ}C$${\pm}$1$^{\circ}C$ and RH 87∼92%, and the sugar content and the change of color was investigated in an interval of one week by taking sample of it after processed it to red ginseng. The total sugar content was 62.71% before it was stored and was a little reduced to 54.58% after 10 weeks of storage. The reducing sugar content was 11.69% before it was stored and was a little reduced to 9.92% after 7 weeks of storage. For the free sugars, the content of fructose was 0.47% before storage and gradually increased to 4.70% after 10 weeks of storage, and the contents of glucose and sucrose were gradually decreased after they have their peak value of 2.31% and 25.89% at five and three weeks of storage. The content of maltose was 6.62% before storage and it gradually reduced to 1.37％ after 10 weeks of storage. The color intensity was generally increased with the storage time, and the total rotor value(ΔE) has its peak value of 8.89 after 9 weeks of storage. For the browning pigment, the absorbance of 420nm and 440nm was increased after 6 weeks of storage. The similar trend was observed at 285nm where the precursor of browning pigment was investigated, however, the change was not observed for the freeze dryed ginseng.

• Korean Journal of Food Science and Technology
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• v.8 no.3
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• pp.129-135
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• 1976

The amino acid compositions of polished barley grain were investigated for 16 varieties by using amino acid autoanalyzer and simple correlation analysis between them and between protein and amino acid per protein was done. 1) Limiting amino acid is lysine, leucine and phenylalanine are high but threonine and tyrosine are low. Total essential amino acids is high. 2) Protein is significantly correlated negatively with lysine arginine, total basic amino acids (at p=0.01) and threonine, alanine, aspartic acid (at p=0.05) and positively with phenylalanine (at p=0.01) proline and cystine (at p=0.05). 3) Lysine is positively and significantly correlated with arginine and aspartic acid indicating that aspartic acid is probable precursor of lysine and that high yielding varieties or fertilization for high yielding decrease aspartic acid pool resulting low lysine. 4) Lysine content is positively correlated with dye binding capacity (at p=0.01). 5) Tryptophan is positively (at p=0.01) and significantly correlated with histidine, total basic amino acids and arginine. 6) In essential amino acids lysine, tryptophan, threonine and valine simultaneously increase or decrease while aromatic amino acids, sulfur contained amino acids, isoleucine and leucine do so together.