• Journal of the Korean Chemical Society
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• v.17 no.3
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• pp.174-181
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• 1973

Dichlorodiacetatotitanium(IV) dissolves in alcohols with chemical reaction. Such solvolytic reaction of $TiCl_2(OAc)_2$with various alcohols has been studied by means of solution NMR spectroscopy and chemical analysis of the isolated products. The reaction of $TiCl_2(OAc)_2$ with primary alcohols has shown to be a quantitative two-step ligand substitution process as shown in the following: $TiCl_2(OAc)_2+ROH{\to}TiCl_2(OAc)_2(OR)+AcOH$ $TiCl_2(OAc)_2(OR)+ROH{\to}TiCl_2(OAc)_2+AcOH$The molecular form initially soluble in organic solvents has been found to be the monosubstituted species $TiCl_2(OAc)(OR)$. Alcoholysis with t-butyl alcohol has shown remarkable differences. When the mole ratio of t-butyl alcohol to $TiCl_2(OAc)_2$ is less than 1/2, the following reaction is dominant. $TiCl_2(OAc)_2+t-ButOH{\to}TiCl_2(OAc)_2+t-ButCl$However, at higher mole ratio another substitution process resembling the first step reaction with primary alcohols is competitively accompanied. The reaction with t-butyl alcohol also differs from that with primary alcohols in that only one either of the two chloro-or acetato-ligands in $TiCl_2(OAc)_2$ is subjected to substitution.

• Journal of the Korean Chemical Society
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• v.16 no.2
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• pp.80-83
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• 1972

The activity change of lysozyme resulted from its exposure to $Ti-H_2O_2$system in aqueous liquid at room temperature and to ${\gamma}$-irradiation in ice at $195^{\circ}K$ has been measured at room temperature with a Cary-14 spectrophotometer. The enzymatic activity of lysozyme which had been added to a previously flow-mixed solution of $TiCl_3$ and $H_2O_2$ (System I) was compared with the activity of a lysozyme-$H_2O_2$ solution after flow-mixing with $TiCl_3$ (System II), considering the differences between these two activity changes as the extent of the enzymatic inactivation by the involvement of OH radical reaction. The fraction of lysozyme inactivated by OH radical in the system containing 0.0025 M $TiCl_3-0.1M$ $H_2O_2$ (ph 3.5) was 13%, When the $TiCl_3$ concentration is double (pH 3.0), the fraction of enzyme inactivated increases to 36%. The activity of the system containing 0.025 M $TiCl_3-0.1$ M $H_2O_2$ (pH 1.5) was essentially zero. The results seem to support the previos view that the production of OH radical should be proportional to $TiCl_3$ concentration when $H_2O_2$ is present in excess. Increase in the extent of inactivation found in system I with increasing $TiCl_3$ concentration may be due to a pH effect. $H_2O_2$ seems to be less effective than $TiCl_3$ in the inactivation. 1% lysozyme solution, when ${\gamma}$-irradiated with a total dose of 3M rads, loses about 20% of its activity. Lowering of temperature also was found to yield a reduction in enzymatic activity.

• Journal of the Korean Chemical Society
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• v.38 no.2
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• pp.101-107
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• 1994

Some molybdenum(III) and (IV) complexes have been prepared from the reaction of $MoCl_4$·2MeCN with N, P, O-donating ligands and characterized by elemental analysis, infrared and UV-Visible spectroscopy. 3,5-Lutidine, 1,2-phenylenediamine, 8-hydroxyquinoline, 9,10-phenanthrenequinone, triphenylphosphine and 1,2-bis(diphenylphosphino)ethane were chosen as coordinating ligands. Stretching frequencies $\upsilon$ (Mo-Cl) of Mo(IV) appear at higher frequencies than those of Mo(III) complexes due to the increasing oxidation number of metal. $MoCl_4(L)_2$ exhibit one Mo-Cl stretching frequency, whereas Mo$Cl_4$(L^L) exhibit four Mo-Cl stretching frequencies. The number of Mo-Cl stretching frequency suggestes the former complexes have trans($D_{4h}$) and the latter complexes have cis($C_{2v}$) symmetry. Stretching frequency ${\nu}g(C{\equiv}N)$ of acetonitrile in Mo(III) complexes are shifted to about 30 $cm^{-1}$ higher frequency compared with that of a free ligand (2260 $cm^{-1}$). These spectral data indicates that Mo(III) complexes are in the octahedral geometries with the coordinated acetonitrile. Finally each molybdenum(III) and (IV) complexes showed the following formulation; $[MoCl_4(L)_2]$,[Mo$Cl_4$(L^L)], $[MoCl_3(L)_2MeCN]$ and [Mo$Cl_3$(L^L)MeCN].

• Development and Reproduction
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• v.16 no.4
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• pp.295-300
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• 2012

Manganese ($Mn^{2+}$) is a trace element that is essential for normal physiology, and is predominantly obtained from food. Several lines of evidence, however, demonstrated that overexposure to $MnCl_2$ exerts serious neurotoxicity, immunotoxicity and developmental toxicity, particularly in male. The present study aimed to evaluate the effect of 0, 1.0, 3.3, and 10 mg/kg/day doses of $MnCl_2$ on the reproductive organs in the immature female rats. Rats (PND 22; S.D. strain) were exposed to $MnCl_2$ ($MnCl_2{\cdot}4H_2O$) dissolved in drinking water for 2 weeks. The animals were sacrificed on PND 35, then the tissues were immediately removed and weighed. Histological studies were performed using the uteri tissue samples. Serum LH and FSH levels were measured with the specific ELISA kits. Body weights of the experimental group animals were not significantly different from those of control group animals. However, ovarian tissue weights in 1 mg and 3.3 mg $MnCl_2$ dose groups were significantly lower than those of control animals (p<0.05 and p<0.01, respectively). Uterine tissue weights of 3.3 mg dose $MnCl_2$ groups were significantly lower than those of control animals (p<0.01), while the 1 mg $MnCl_2$ dose and 10 mg $MnCl_2$ dose failed to induce any change in uterine weight. Similarly, only 3.3 mg $MnCl_2$ dose could induce the significant decrease in the oviduct weight compared to the control group (p<0.05). Non-reproductive tissues such as adrenal and kidney failed to respond to all doses of $MnCl_2$ exposure. The uterine histology revealed that the $MnCl_2$ exposure could affect the myometrial cell proliferation particularly in 3.3 mg dose and 10mg dose group. Serum FSH levels were significantly decreased in 1mg $MnCl_2$ dose and 10 $MnCl_2$ mg groups (p<0.05 and p<0.01, respectively). In contrast, treatment with 1 mg $MnCl_2$ dose induced a significant increment of serum LH level (p<0.05). The present study demonstrated that $MnCl_2$ exposure is capable of inducing abnormal development of reproductive tissues, at least to some extent, and altered gonadotropin secretions in immature female rats. Combined with the well-defined actions of this metal on GnRH and prolactin secretion, one can suggest the $Mn^{2+}$ might be a potential environmental mediator which is involved in the female pubertal process.

• Journal of the Korean Chemical Society
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• v.63 no.3
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• pp.160-165
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• 2019

A series of reactions between an amino alcoholic ligand, cis-2-((2-((2-hydroxyethyl)amino)ethyl)amino)cyclohexan-1-ol (HEAC), with the mixtures of group 12 metals including, $HgCl_2/CdCl_2$, $HgCl_2/CdI_2$, $ZnCl_2/CdCl_2$ and $ZnCl_2/CdCl_2/HgCl_2$ was experimentally and theoretically studied to determine the most stable product of these reactions. Furthermore, the Cambridge Structural Database (CSD) studies were done to evaluate the theoretical results. The products were characterized by elemental analysis, FT-IR, Raman, $^1H$ NMR spectroscopy and single-crystal X-ray diffraction. Based on these investigations a binuclear structure of cadmium, [$Cd_2(HEAC)_2({\mu}-Cl)_2Cl_2$] (1), is the most stable product that was formed in all studied reactions between HEAC and metals mixtures. In this structure, the cadmium atom has a $CdN_2O({\mu}-Cl)_2Cl$ environment and distorted octahedral geometry.

• Journal of Integrative Natural Science
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• v.4 no.3
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• pp.177-181
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• 2011

The catalytic dehydrocoupling of bis(1-sila-3-butyl)benzene 1 and 2-phenyl-1,3-disilapropane 2 by $Cp_2ZrCl_2$/Red-Al and $Cp_2ZrCl_2$/n-BuLi was reported to compare their catalytic efficiency. The dehydrocoupling of monomeric silanes 1 with the $Cp_2ZrCl_2$/Red-Al and $Cp_2ZrCl_2$/n-BuLi combination catalysts produced two phases of polymers: one is a highly cross-linked insoluble solid, and the other is noncross-linked or slightly cross-linked soluble oil and could be a precursor for the solid polymer. The dehydrocoupling of 2 with the $Cp_2ZrCl_2$/n-BuLi combination catalyst similarly produced two phases of polymers. By contrast, the catalytic reaction of 2 with the $Cp_2ZrCl_2$/Red-Al combination catalyst produced a soluble polymer via redistribution/dehydrocoupling process.

• KSBB Journal
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• v.27 no.1
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• pp.28-32
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• 2012

In this study, the treatment ability of the wastewater containing perchlorate by non-salt tolerant perchlorate reducing bacterial consortium (N-PRBC) was evaluated in a continuous stirred tank bioreactor (CSTR). To obtain the optimal operating condition the bioreactor was operated with the different wastewater empty bed retention time (EBRT). The treatment performance in the bioreactor could be maintained at 100 $mg-ClO_4{^-}L^{-1}$ up to a EBRT of 3 h, and the removal capacity in the CSTR was about 3.3 times higher than that in a batch operation. With a decrease from 9 h to 2 h in a EBRT, the volumetric perchlorate reduction rate was increased from 11.1 $mg-ClO_4{^-}L^{-1}h^{-1}$ to 50.0 $mg-ClO_4{^-}L^{-1}h^{-1}$, and the specific perchlorate reduction rates were increased from 3.01 $mg-ClO_4{^-}g-DCW^{-1}h^{-1}$. In conclusion, the treatment capacities in a CSTR were much better than those obtained in a batch operation.

• Nuclear Engineering and Technology
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• v.46 no.3
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• pp.395-406
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• 2014

This study provides a fundamental understanding of a cold finger melt crystallization technique by exploring the heat and mass transfer processes of cold finger separation. A series of experiments were performed using a simplified LiCl-CsCl system by varying initial CsCl concentrations (1, 3, 5, and 7.5 wt%), cold finger cooling rates (7.4, 9.8, 12.3, and 14.9 L/min), and separation times (5, 10, 15, and 30 min). Results showed a potential recycling rate of 0.36 g/min with a purity of 0.33 wt% CsCl in LiCl. A CsCl concentrated drip formation was found to decrease crystal purity especially for smaller crystal formations. Dimensionless heat and mass transfer correlations showed that separation production is primarily influenced by convective transfer controlled by cooling gas flow rate, where correlations are more accurate for slower cooling gas flow rates.

• Journal of Environmental Science International
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• v.11 no.4
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• pp.347-353
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• 2002

This study was conducted to investigate the characteristics of chloramination as a secondary disinfection in a drinking water distribution system. At the range from pH 6 to pH 8, monochloramine was predominant with a trace of dichloramine, and the free chlorine was detected after breakpoint. At $25^{\circ}C$, the breakpoints of pH 6, 7 and 8 appeared when the weight ratios of chlorine to ammonia nitrogen were 11:1, 9:1 and 10:1 respectively, and the peak points on the breakpoint curves at pH 6, 7 and 8 were in the Cl$_2$ / NH$_3$-N ratio of 9:1, 6:1 and 5:1 respectively. As pH increased from 6 to 8, maximum point of monochloramine on the breakpoint curve was moved from 7:1 to 5:1 in the weight ratio of chlorine to ammonia nitrogen. The maximum concentration of monochloramine was formed at the pH values of 7~8 and in the Cl$_2$ / NH$_3$-N ratio below 5:1. As the Cl$_2$/NH$_3$-N ratio increased and the pH lowered, chloramines decay proceeded at an increased rate, and residual chloramines lasted longer than the residual free chlorine. The monochloramine and the dichloramine were formed at pH 6, and then the dichloramine continued increasing with contact time.

• Journal of Microbiology and Biotechnology
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• v.29 no.2
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• pp.191-199
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• 2019

We inoculated different combinations of three starter candidates, Bacillus licheniformis, Staphylococcus succinus, and Tetragenococcus halophilus, into sterilized soybeans to predict their contributions to volatile compound production through soybean fermentation. Simultaneously, we added NaCl to soybean cultures to evaluate its effect on the volatile compounds profile. Cells in soybean cultures (1.5% NaCl) nearly reached their maximum growth in a day of incubation, while cell growth was delayed by increasing NaCl concentrations in soybean cultures. The dominance of B. licheniformis and S. succinus in the mixed cultures of three starter candidates switched to T. halophilus as the NaCl concentration increased from 1.5% to 14% (w/w). Seventeen volatile compounds were detected from the control and starter candidate-inoculated soybean cultures with and without the addition of NaCl. Principal component analysis of these volatile compounds concluded that B. licheniformis and S. succinus made major contributions to producing a specific volatile compound profile from soybean cultures where both species exhibited good growth. 3-Hydroxybutan-2-one, butane-2,3-diol, and 2,3,5,6-tetramethylpyrazine are specific odor notes for B. licheniformis, and 3-methylbutyl acetate and 2-phenylethanol are specific for S. succinus. Octan-3-one and 3-methylbutan-1-ol were shown to be decisive volatile compounds for determining the involvement of S. succinus in the soybean culture containing 7% NaCl. 3-Methylbutyl acetate and 3-methylbutan-1-ol were also produced by T. halophilus during soybean fermentation at an appropriate level of NaCl. Although S. succinus and T. halophilus exhibited growth on the soybean cultures containing 14% NaCl, species-specific volatile compounds determining the directionality of the volatile compounds profile were not produced.