• Applied Biological Chemistry
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• v.38 no.2
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• pp.100-105
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• 1995

Media optimization for the production of MR-387A and B, novel aminopeptidase M inhibitors by Streptomyces sp. SL-387 isolated from a soil was studied. Optimized medium was consisted of 1% glucose, 3% soybean meal, 0.2% yeast extract, 0.1% beef extract, 0.3% NaCl, 0.01% $K_2HPO_4$, 0.3% $CaCO_3$, 0.001% $MnCl_2{\cdot}4H_2O$, 0.001% $ZnCl_2{\cdot}7H_2O$, and 0.0005% $MgSO_4{\cdot}7H_2O$, and adjusted to pH 7.0 before autoclaving. When the optimized medium was used as a fermentation medium, maximum productivity of MR-387 was reached at 120 hours of fermentation, and total productivity was 909.1 U/ml.

• Journal of the Korean institute of surface engineering
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• v.30 no.2
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• pp.111-120
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• 1997

The growth kinetion of $CuCl_x$ layer on Cu was investigated using $Cl_2$ gas with/without plasma. The etching kinetics ofit was also studied, in which PEt3 gas as well as $Cl_2$ gas were used. when plasma and DC bias were applied, not only the growth rate of $CuCl_x$ layer but also the surface concentration of Cl in $CuCl_x$ layer drastically increased. The growth mode is divided into three regimes, where the thinkness $CuCl_x$ layer ise proportional to t, lo9g $T^{1/2}$ , respectively, whether plasma, is applied or not. These three regime. It is also identified that the eath rate of Cu is drastically increased as the $Cl_2$ pressure is increased. However, when plasma and DC bias were applied, the etching rate is decreased, and ClCu-P-U layer is formed. in addition, as the etching time is increased, the surface concentration of Cl is increased and $CuCl_2$ formed partially.

• Restorative Dentistry and Endodontics
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• v.17 no.1
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• pp.1-9
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• 1992

The intradental nerve activity was recorded from single pulp nerve unit dissected from the inferior alveolar nerve in canine teeth of anesthetized cats. The effects of various test solutions on intradental nerve activity evoked by 4M NaCl applied to the deep dentinal cavities were investigated. 1. Total 15 single pulp nerve units were recorded. Of these 9 were Mi - fibers and 6 were C -fibers. The mean conduction velocity and electrical threshold of $A{\delta}$ - fiber were $6.3{\pm}3.7m/sec$, $1.2{\pm}0.7V$ and those of C - fiber were $1.0{\pm}0.2m/sec$, $2.3{\pm}1.3V$, respectively. The response to cold stimuli of $A{\delta}$ - fiber began immediately and that of C - fiber began after a latency. 2. When applied to deep dentinal cavity, 4M NaCl induced irregular bursts of action potential in 4 $A{\delta}$ - fibers and 3 C - fibers, which continued until the solution was washed away. 3. In the $A{\delta}$ - fiber, histamine failed to induce any nerve acitivity and did not produce an increase in intradental nerve activity evoked by 4M NaCl. However following the application of 1M KCl, the response to 4M NaCl was eliminated. 4. In the C - fiber, histamine generated some nerve activity and produced a significant increase in intradental nerve activity evoked by 4M NaCl, but 5M $CaCl_2$ did not abolish this enhandced response.

• Korean Chemical Engineering Research
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• v.54 no.1
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• pp.135-139
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• 2016

We developed a liquid-liquid extraction method using an inorganic salt to dramatically improve the recovery efficiency of the anticancer agent paclitaxel from plant cell cultures. As a result of liquid-liquid extraction using a diverse types of inorganic salt (NaCl, KCl, $K_2HPO_4$, $NaH_2PO_4$, $NaH_2PO_4{\cdot}2H_2O$), NaCl gave the highest yield (~96%) and lowest partition coefficient (0.053) of paclitaxel. The optimal NaCl/solvent ratio, methylene chloride/MeOH ratio, and pure paclitaxel content for liquid-liquid extraction using NaCl were 1% (w/v), 26% (v/v), and 0.066% (w/v), respectively. Under the optimal conditions developed in the present method, most of the paclitaxel (~96%) was recovered from biomass by a single extraction step. In addition, this method facilitated 3-fold higher recovery efficiency of paclitaxel in a shorter extraction number than the conventional liquid-liquid extraction method.

• Journal of Soil and Groundwater Environment
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• v.9 no.2
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• pp.11-19
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• 2004

Chlorinated and nitroaromatic compounds are non-degradable substances that are extremely toxic and are known to be carcinogens and mutation causing agents. Moreover, the half-lives of substances such as carbon tetrachloride, hexachloroethane and nitroaromatic compounds are several decades. In this study, the optimal conditions to detoxify chlorinated compounds by the reductive degradation were investigated. The following results were obtained in the reductive degradation of CCl$_4$, C$_2$Cl$\_$6/, C$_2$HCl$\_$5/, C$_2$Cl$_4$, and C$_2$HCl$\_$5/ by using Fe, FeS and FeS$_2$ as mediators. CCl$_4$ was reduced to CH$_2$Cl$_3$ and CH$_2$Cl$_2$in anaerobic conditions when FeS was used as a mediator. While the reduction of CCl$_4$ to CHCl$_3$ was rapidly proceeded, the reduction of CHCl$_3$ to CH$_2$Cl$_2$ was occurred slowly. Further reduction to CH$_3$Cl was not observed. Unlike CCl$_4$, C$_2$Cl$\_$6/ was degraded to C$_2$HCl$\_$5/, C$_2$Cl$_4$. C$_2$HCl$_3$ and cis-1,2-C$_2$H$_2$Cl$_2$ by complicated pathways such as hydrogenolysis, dehalo-elimination and dehydrohalogenation. A small amount of C$_2$HCl$\_$5/ was detected only in the early stages of the reduction. However, majority of the C$_2$Cl$\_$6/ was reduced to C$_2$Cl$_4$. cis-1,2-C$_2$H$_2$C1$_2$ was the only product among other possible isomers.

• Journal of the Korean Chemical Society
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• v.29 no.4
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• pp.348-355
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• 1985

Extended Huckel Calculation of cis-and trans-dichloro diammine platinum(II), dichloroethylene diamine platinum(II) and their N-mono, di, tri and tetra-methylated or ethylated ones were carried out to investigate their anticancer activity. It was found that the net charge of two chlorine atoms in cis-isomers are greater than those in trans-ones and Pt-Cl bond energies of the former are less than that of the latter, indicating that Pt-Cl bond in cis-isomers has greater ionic character than that in trans-ones and Cl atoms in the former are easier to dissociated as Cl- than those in the latter. Also, the values of $b_{2g}-b_{1g}$ energy difference, ${\Delta}_1$ were found to be greater in cis-isomers than in trans-one without exceptions. For the substitution of methyl for H atom in ammine and ethylenediamine Pt-Cl bond strength shows the tendency to increase with increasing in number of methyl group. Accordingly, We believe that two Cl atoms in $PtLCl_2$-complexes (L: NH$_3$, en) are dissociated in the first step of the action of anticancer.

• Resources Recycling
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• v.18 no.1
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• pp.30-37
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• 2009

Distribution diagram of Pt(IV), Pd(II), and Rh(III) in HCl solution was obtained as a function of HCl concentration from 0.001 to 10 M by considering complex formation reaction together with mass balance. When HCl concentration was higher than 0.1 M, most of Pt and Pd in HCl solution exist as $PtCl_6^{2-}$ and $PtCl_4^{2-}$. The concentration of HCl had a feat effect on the speciation of Rh(III). As HCl concentration increases from 0.1 to 10 M, the pedominant species changes from $PhCl_5^{2-}$ to $PhCl_6^{3-}$. Interaction parameters of $PtCl_6^{2-}$ and $PdCl_4^{2-}$ with hydrogen ion were evaluated from the solvent extraction data of Pt and Pd reported in the literature.

• Bulletin of the Korean Chemical Society
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• v.1 no.2
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• pp.45-49
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• 1980

During the homolytic reactions of $CCl_4$ or $Cl_3CBr with ${\beta}-halo^1$-styrenes,$\beta$-haloradicals are key intermediates. They are to be stabilized via three pathways; $\beta$-cleavage, halogen transfer and telomerization. The three reaction paths are delicately controlled by the energetics of their formation and stabilization. When the formation of a $\beta$-haloradical is accompanied by considerable excess of energy from an exothermic reaction, $\beta$ -cleavage is often dominant over the halogen transfer. On the other hand, if the radical forms via a reversible reaction, two processes become competitive. $\beta$-Eliminated bromine atoms from ${\beta}$ -bromoradicals generate $Br_2$ via $Cl_3CBr + {\cdot}Br {\leftrightarrow} Br_2 + {CCl_3}{\cdot}{Br_2}$ may act as a better scavenger than Cl3CBr for the ${\beta}$-bromoradicals. Different reactivities of chlorine, bromine and trichloromethyl radicals towards olefinic pi-bond are clarified in terms of the beat content of the addition reactions.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.3
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• pp.233-243
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• 2014

The difference of mooring tension by type of buoy was investigated in the circulating water channel and the wave tank for deducting the most stable buoy from the current and the wave condition. 5 types of buoy made up of short cylinder laid vertically (CL-V), short cylinder laid horizontally (CL-H), capsule (CS), sphere (SP) and long cylinder (CL-L) were used for experiments. A mooring line and a weight were connected with each buoy. A tensile gauge was installed between a mooring line and a weight. All buoy's mooring tension was measured at the same time for the wave test with periods of 1.5~3.0 sec and wave heights of 0.1~0.3 m, and the current test with flow speeds of 0.2~1.0 m/sec. As a result, the order of tension value in the wave test was CL-H > CL-V > SP > CS > CL-L. In the current test CL-V and CL-H were recorded in the largest tension value, whereas SP has the smallest tension value. So it seems that SP buoy is the most effective in the location affected by fast current. CS is predicted to be suitable for a location that influence of wave is important more than that of current if practical use in the field is considered. And it was found that the difference of mooring tension among buoys in wave is related to the product of the cross sectional area and the drag coefficient for the buoy's bottom side in high wave height. The factor for the current condition was not found. But it was supposed to be related to complex factors like a dimension and a shape by buoy's posture to flow.

• Journal of Mushroom
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• v.2 no.1
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• pp.4-9
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• 2004

This study was carried out to investigate effect of NaCl treatment on growth oyster mushroom and Trichoderma spp. on PDA and in rice straws. We also investigated the possibility of oyster mushroom cultivation using rice straw harvested from the reclaimed land having been drained sea water. Mycelial growth of oyster mushroom was increased by treatment of 0.2% NaCl but decreased by treatment of the higher concentration of NaCl. In the case of the mycelial growth on PDA of Trichoderma spp., no change was found in 0.5%~1.0% NaCl, but decreased in the range of 1.0%~3.0% NaCl and drastically decreased at 5.0% NaCl. In the rice straws treated with different concentration of NaCl solution, mycelial growth of oyster mushroom showed almost same result compare to PDA. The spore formation of Trichoderma mould was almost same in both 0% and 0.3% NaCl, decreased in 0.5% and was not found spores in the higher concentration of NaCl. As increasing salt concentration in the rice straws, the NaO contents were increased. The $K_2O$ contents were decreased before and after sterilization. The moisture content of rice straws showed no difference by treatment of 3.0% NaCl but decreased the moisture by treatment of 5.0% NaCl. No pH change was found in the rice straws treated with NaCl. Mushroom yield in the rice straw of reclaimed land was a little higher than that of normal paddy land straw. The duration of primordium formation was not affected by NaCl concentration in rice straws. The yield of fruiting body in 0.3% NaCl treatment was 2,700kg, which was almost same to non-treated plot, but decreased in 0.5% NaCl. EC value of soaking water after submerging rice straw was higher than before, but NaO content was not changed at both condition.