• Title/Summary/Keyword: NaB$H_{4}$

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Synthesis and Structure of Tetrahomodioxa p-phenylcalix(4)arene dihexylether (Tetrahomodioxa p-phenylcalix(4) arene dihexylether의 합성 및 구조에 관한 연구)

  • 노광현;박영자
    • Korean Journal of Crystallography
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    • v.13 no.3_4
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    • pp.158-164
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    • 2002
  • Tetrahomodioxa p-phenylcalix(4)arene dihexylether(C/sub66/H/sub68/O/sub6/) has been synthesized and structurally characterized by X-ray diffraction. Reaction of tetrahomodioxa p-phenylcalix(4)arene with hexyl halide and NaH in DMF leads to the dihexyl derivatives, 7,13,21,27-tetraphenyl-29,31-dihexyloxy- 2,3,16,17-tetrahomo-3,17-dioxacalit(4)arenes. The crystal is orthorhombic, P2₁2₁2₁, a= 9.764(2), b=16.167(2), c=32.994(3) Å, V=5208(1) Å, Z= 4, Dc = 1.221 gcm/sup -3/. The structure was solved by direct methods and refined by full-matrix least squares. Refinement converged at R = 0.070 for 2009 observed reflections. This molecule has a C-1,2-alternate conformation with pseudo-centrosymmetry and has two pairs of opposite phenyl rings, which are approximately parallel to each other. The benzene rings A and B are up, and the rings C and D rings are down with respect to the plane of the macrocyclic ring.

Development of Ginseng yogurt fermented by Bifidobacterium spp (Bifidobacterium을 이용한 인삼 요구르트의 개발)

  • Kim, Na-Young;Han, Myung-Joo
    • Korean journal of food and cookery science
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    • v.21 no.5
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    • pp.575-584
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    • 2005
  • The objective of this study was to develop bioactive ginseng yogurt, fermented by B. minimum KK-1 and B. cholerium KK-2, which showed transforming activity of ginseng extract to compound K. Among older people, 3% ginseng yogurt fermented by B. minimum KK-1 and mixed with Bifidobacterium KK-1, KK-2 showed the highest overall acceptability(6.80, 6.80) among 1%(3.87, 3.67), 2%(4.40, 4.53) and 3% ginseng yogurt. The pH of ginseng yogurt was lower than that of plain yogurt. During 9 days of storage, the pH of each yogurt slightly decreased and then increased until 15 days of storage. The 3 8.25 log CFU/g and B. cholerium KK-2; 7.78 log CFU/g). Therefore, ginseng might be used as a growth factor during the fermentation of yogurt. The L value of ginseng yogurt decreased, and the a and b values increased, with increasing ginseng concentration.

Origin of B, Br and Sr in Groundwater from Bukahn-myeon, Yeongcheon, Gyeongbuk Province, with Emphasis on Hydrochemistry (지하수의 수질화학적 특징과 붕소, 브롬, 스트론튬 성인에 대한 고찰)

  • Choo, Chang-Oh;Lee, Jin-Kook;Lee, Chang-Joo;Park, Ki-Ho;Jeong, Gyo-Cheol
    • The Journal of Engineering Geology
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    • v.19 no.2
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    • pp.235-250
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    • 2009
  • Environmental elements such as B, Br, and Sr in groundwater from Bukahn-myeon, Yeongcheon, Gyeongbuk Province, were investigated in order to know their origin with emphasis on hydrochemistry. pH ranges from 7.37 to 8.39. B content is 0.41${\sim}$4.62 mg/L with an average 1.74 mg/L and Br content is 0${\sim}$3.24 mg/L with an average 2.22 mg/L, and Sr content is 0.93${\sim}$8.64 mg/L with an average 2.76 mg/L. The water types plotted by the Piper diagram are different but mostly $Ca-HCO_3$. Some constituents contributing to EC are Na, $SO_4$, Cl with high determinative coefficients($R^2$) of 0.85, 0.70, 0.90, respectively. The coefficients($R^2$) of Cl to Na, K, $SO_4$ are 0.54, 0.68, 0.53, respectively. It should be noted that there are high cocfficients($R^2$) of B-Sr and $Sr-SO_4$ with 0.65, 0.64, respectively. The Cl/Br ratios are 5.21${\sim}$30.70 due to significant depletion of Cl. The $SO_4/Cl$ ratios are 1.32${\sim}$27.24 with an average of 5.92, ascribed to abundant introduction of $SO_4$ or significant depletion of Cl. Chemical speciation calculated shows that B exists mostly as $H_3BO_3$ with less $H_2BO^-_3$ and Br exists as only $Br^-$. Sr exists mostly as $Sr^2$ with less $SO_4$. Saturation index represents that goundwater is supersaturated with respect to barite, kaolinite, illite, K-mica, and smectite while it is slightly undersaturated with respect to silica, gypsum, anhydrite, talc, chrysotile, feldspar, kaolinite, illite, K-mica, and smectite. The saturation index of celestine is -2.23${\sim}$-0.13 indicating more Sr can be incorporated into groundwater. Groundwater is still much undersaturated to halite. It is likely that the origin of S and Sr was related to the Yucheon volcanic rocks. Br might be originated from the local geological features with introduction of anthropogenic matters.

Behavior of Burkholderia thailandensis (Burkholderia pseudomallei surrogate) in Acidified Conditions by Organic Acids Used in Ready-to-Eat Meat Formulations under Different Water Activities

  • Yoon, Yo-Han
    • Food Science of Animal Resources
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    • v.30 no.6
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    • pp.946-950
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    • 2010
  • This study evaluated the antimicrobial effects of meat processing-related organic acids on Burkholderia thailandensis (Burkholderia pseudomallei surrogate) with different water activities. B. thailandensis KACC12027 (4 log CFU/mL) was inoculated in microwell plates containing tryptic soy broth pH-adjusted to 4, 5, 6, and 7 with ascorbic acid, citric acid, and lactic acid and with water activities adjusted to 0.94, 0.96, 0.98, and 1.0 with NaCl, followed by incubation at $35^{\circ}C$ for 30 h. The optical density (OD) of the samples was measured at 0, 3, 6, 12, 24, and 30 h at 595 nm to estimate the growth of B. thailandensis. Growth of B. thailandensis was observed only at water activity of 1.0. In general, more bacterial growth (p<0.05) was observed at pH 6 than at pH 7, and the antimicrobial effects of the organic acids on B. thailandensis were in the following order: Ascorbic acid > lactic acid > citric acid after incubation at $35^{\circ}C$ for 30 h. These results indicate that organic acids in meat processing-related formulations should be useful in decreasing the risk related to an emerging high risk agent (B. pseudomallei).

Estimation of deep reservoir temperature of thermal groundwaters in Bugok and Magumsan areas, South Korea

  • Park, Seong-Sook;Yun, Seong-Taek;So, Chil-Sup
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.04a
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    • pp.473-476
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    • 2004
  • In this study, hydrochemical studies of thermal waters in the Bugok and Magumsan areas showing geothermal anomalies were carried, and the applicability of ion seothermometers and multiple mineral equilibrium approach was examined to estimate their potential deep reservoir temperatures. Typical thermal waters of the two areas are clearly grouped into two major types, according to water chemistry: Na-Cl type (group A) and Na-SO4 type (group D). Compared to group A, group B and C waters show some modifications in chemistry. Group E waters show the modified chemistry from group D. Geothermal waters from the two areas showed some different chemical characteristics. The thermal waters of group A and B in Magumsan area are typically neutral to alkaline (pH=6.7 to 8.1) and Cl-rich (up to 446.1 mg/L), while the waters of group D and E in Bugok area are alkaline (pH=7.6 to 10.0) and SO$_4$-rich (up to 188.0 mg/L). The group A (Na-Cl type) and group D (Na-SO$_4$ type) waters correspond to mature or partially immature water, whereas the other types are immature water. The genesis of geothermal waters are considered as follows: group A and B waters were formed by seawater infiltration into reservoir rocks along faults and fracture zones and possibly affected by fossil connate waters in lithologic units through which deep hot waters circulate; on the other hand, group D and E waters were formed by the oxidation of sulfide minerals (mainly pyrite) in surrounding sedimentary rocks and/or hydrothermal veins occurring along restricted fracture channels and were possibly affected by the input and subsequent oxidation of S-bearing gases (e.g. H2S) from deep thermal reservoir (probably, cooling pluton). The application of quartz, Na-K, K-Mg geothermometers to the chemistry of representative group A and D waters yielded a reasonable temperature estimate (99-147$^{\circ}C$ and 90-142$^{\circ}C$) for deep geothermal reservoir. Aqueous liquid-rich fluid inclusions in fracture calcites obtained from drillcores in Bugok area have an average homogenization temperature of 128$^{\circ}C$, which corresponds to the results from ion geothermometers. The multiple mineral equilibrium approach yielded a similar temperature estimate (105-135$^{\circ}C$ and 100-14$0^{\circ}C$). We consider that deep reservoir temperatures of thermal waters in the Magumsan and Bugok areas can be estimated by the chemistry of typical Na-Cl and Na-SO$_4$ type waters and possibly approach 105-135$^{\circ}C$ and 100-14$0^{\circ}C$.

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The Effect of NaCI on the Chl Fluorescence of Barley (Hordeum vulgare L.) Leaves (NaCI이 보리(Hordeum vulgare L.) 잎의 엽록소 형광에 미치는 영향)

  • Chung Hwa-Sook;Lim Young-Jin;Park Kang-Eun;Park Shin-Young
    • Journal of Environmental Science International
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    • v.13 no.12
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    • pp.1015-1021
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    • 2004
  • This study was conducted to investigate the changes of chlorophyll contents and chlorophyll fluorescence in barley(Hordeum vulgare L.) 7 day old seedling treated with 0.2M, 0.4M, 0.6M, 0.8M, and 1.0M NaCI concentration containing Hepes buffer(pH 7.5). Barley was affected by NaCI treatment. The chlorophyll a, b and carotenoid of barley decreased with an increase in NaCI concentration. However, chlorophyll a, b and carotenoid of barley were not greatly influenced by o.8M and 1.0M NaCl. Fv, Fv/Fm and qP were gradually decreased by higher concentration of NaCI. qP, qNP, qR and qE were gradually decreased by 6hr. During barley chloroplast was development NaCI affected chlorophyll synthesis than photosynthetic activity. Whereas barley seedling leaves were more influenced photosynthetic activity than chlorophyll contents by NaCI.

Ru-Sn-Sn 전극을 이용한 염료의 색 제거

  • Park, Yeong-Sik;Kim, Dong-Seok
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2008.11a
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    • pp.233-236
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    • 2008
  • Ru:Sn:Sb 전극의 성능에 영향을 미치는 인자에 대하여 조사하여 다음의 결과를 얻었다. 0.5-3 A로 전류를 변화시켰을 때 최적 전류는 2 A로 나타났다. 실험에 사용한 전해질의 RhB 분해 성능은 NaCl > KCl > HCl > Na$_2$SO$_4$로 나타났다. 최적 NaCl 농도는 1.75 g/L로 나타났다. 최적 공기 공급량은 2 L/min으로 최적 pH는 3으로 나타났다.

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Effect of Additives on the Characteristics of Amorphous Nano Boron Powder Fabricated by Self-Propagating High Temperature Synthesis (자전연소합성법을 이용한 비정질 나노 붕소 분말 특성에미치는 첨가제의 영향)

  • Joo, Sin Hyong;Nersisyan, Hayk H.;Lee, Tae Hyuk;Cho, Young Hee;Kim, Hong Moule;Lee, Huk Hee;Lee, Jong Hyeon
    • Korean Journal of Materials Research
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    • v.25 no.12
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    • pp.659-665
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    • 2015
  • The self-propagating high temperature synthesis approach was applied to synthesize amorphous boron nano-powders in argon atmospheres. For this purpose, we investigated the characteristics of a thermally induced combustion wave in the $B_2O_3+{\alpha}Mg$ system(${\alpha}=1.0-8.0$) in an argon atmospheres. In this study, the exothermic nature of the $B_2O_3-Mg$ reaction was investigated using thermodynamic calculations. Experimental study was conducted based on the calculation data and the SHS products consisting of crystalline boron and other compounds were obtained starting with a different initial molar ratio of Mg. It was found that the $B_2O_3$ and Mg reaction system produced a high combustion temperature with a rapid combustion reaction. In order to regulate the combustion reaction, NaCl, $Na_2B_4O_7$ and $H_3BO_3$ additives were investigated as diluents. In an experimental study, it was found that all diluents effectively stabilized the reaction regime. The final product of the $B_2O_3+{\alpha}Mg$ system with 0.5 mole $Na_2B_4O_7$ was identified to be amorphous boron nano-powders(< 100 nm).

Palladium(II) Schiff Base Complexes Derived from Allylamine and Vinylaniline

  • Uh, Yoon-Seo;Zhang, Hai-Wen;Vogels, Christopher M.;Decken, Andreae;Westcott, Stephen A.
    • Bulletin of the Korean Chemical Society
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    • v.25 no.7
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    • pp.986-990
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    • 2004
  • Condensation of salicylaldehyde $(2-HOC_6H_4C(O)H)$ with allylamine afforded the unsaturated salicylaldimine, $2-HOC_6H_4C(H)=NCH_2CH=CH_2$. Similar reactivity was observed with substituted salicylaldehydes. Further reaction of these Schiff bases with palladium acetate or $Na_2PdCl_4$ afforded complexes of the type $PdL_2$, where L = deprotonated Schiff base. The molecular structure of the parent salicylaldimine palladium complex $[trans-(2-OC_6H_4C(H)=NCH_2CH=CH_2)_2Pd]$ (1) was characterized by an X-ray diffraction study. Crystals of 1 were monoclinic, space group $P2_1/n,\;a\;=\;14.0005(9)\;{\AA},\;b\;=7.2964(5)\;{\AA},\;c\;=\;17.5103(12)\;{\AA},\;{\beta}\;=\;100.189(1)^{\circ}$, Z = 4. Analogous chemistry with 4-vinylaniline also gave novel palladium complexes containing a pendant styryl group. Crystals of $[trans-(2-HOC_6H_4C(H)=N-4-C_6H_4CH=CH_2)_2Pd]$ (4) were monoclinic, space group $P2_1/c$, a = 13.7710(14) ${\AA}$, b = 11.0348(11) ${\AA}$, c = 7.8192(8) ${\AA}$, ${\beta}\;=\;98.817(2)^{\circ}$, Z = 2.

Comparative Studies on the Enzymatic Properties of two Trypsin-like Enzymes from Menhaden, Brevoortia tyranus (혈합육어 멘헤이든의 장기조직분포Trypsin-유사효소에 관한 비교효소학적 연구)

  • PYEUN Jae-Hyeung;KIM Hyeung-Rak;GODBER J. S.
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.23 no.1
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    • pp.12-24
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    • 1990
  • Two trypsin-like enzymes, designated trypsin A and 3, purified from the intestine of menhaden by $(NH_4)_2SO_4$ fractionation, Benzamidine-Sepharose 6B affinity chromatography, DEAE-Sephacel ion exchange chromatography and Sephadex G-75 gel filtration chromatography. The two trypsins were subjected to compare the enzymatic properties of the trypsin-like enzymes from the other dark fleshed fishes. Both trypsins catalysed the hydrolysis of N$\alpha$-benzoyl-DL-arginine-p-nitroanilide and they were remarkably inhibited by several well known trypsin-inhibitors, tosyllysyl chloromethyl ketone, soybean trypsin inhibitor, be-nzamidine, leupeptin and antipain, etc. Therefore, it was ascertained that the two enzymes are serine-type trypsins. The molecular weights of these enzymes were about 25,000 and 26,200, respectively, ;Is determined by SDS-PAG electrophoresis and by Sephadex G-100 gel filtration, and the molecular weights of these two enzymes are somewhat fewer than those from the other dark fleshed fishes. Both enzymes had less basic amino acids such as arginine and Iysine, whereas they had slightly high contents of neutral amino acids, glycine, alanine and tryptophane. The enzymes showed a pH optimum of $8\~11$ at $60^{\circ}C$ against the $N\alpha$-benzoyl-DL-argi-nine-p-nitroanilide substrate and they were quite unstable above $40^{\circ}C$ and under the atidic pH region. The Km constant of the two enzymes against the $N\alpha$-benzoyl-DL-arginine-p-nitroanilide was $1.4\times10^{-4}M$ for trypsin A and $4.3\times10^{-5}M$ for trypsin B, respectively.

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