• Bulletin of the Korean Chemical Society
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• v.29 no.8
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• pp.1464-1466
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• 2008

Tetrabutylammonium Fluorodichloroplumbate(II), N$(C_4H_9)_4$[$PbCl_2F$], TBAFDiCP and Tetrabutylammonium Fluorodiiodoplumbate(II), [$(C_4H_9)_4$N][$PbI_2F$], TBAFDiIP are the first examples of fluoroplumbate salts that have been prepared from the reaction of $(C_4H_9)_4$NF with $PbCl_2$ and $PbI_2$ respectively using either $CH_3CN$ solvent. These new compound characterized by elemental analysis, IR, UV/Visible, $^1H$ NMR, and $^{19}F$ NMR techniques.

• Journal of the Korean Chemical Society
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• v.7 no.4
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• pp.293-298
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• 1963

The crystal structure of ethylenediamine dihydrochloride has been determined by the two-dimensional Patterson methods and refined by two-dimensional Fourier syntheses. The unit cell dimensions are a = 4.44${\pm}$0.02, b = 6.88${\pm}$0.02, c = 9.97${\pm}$0.02 ${\AA}$, ${\beta}$ = 92${\pm}$$1^{\circ}$. The space group is $P2_1_{/c}$. The carbon and nitrogen atoms in the ethylenediamine itself lie on one plane and its structure has a trans-form with a centre of symmetry in it, and C-C distance of 1.54 ${\AA}$, C-N distance of 1.48${\AA}$ and C-C-N bond angle of $109.07^{\circ}$. The molecules are linked by N-H${\cdots}$Cl hydrogen bonds with distance of 3.14, 3.16 and 3.22 ${\AA}$ forming three dimensional network. The values of reliability factor for F(okl), F(hol) and F(hko) are 0.11, 0.10 and 0.09 respectively.

• Journal of Electrochemical Science and Technology
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• v.3 no.4
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• pp.185-189
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• 2012

A.c. impedances of mechanically polished CP-Ti specimens were measured at open-circuit potential (OCP) with immersion time and under applied anodic potentials between -0.2 and 1 $V_{Ag/AgCl}$ in 0.1 M NaOH solution. Capacitances of native oxide films ($C_{ox,na}$) grown naturally and capacitances of anodic oxide films ($C_{ox,an}$) formed under applied anodic potentials were obtained to examine the growth of native and anodic oxide films in 0.1 M NaOH solution and how to use $C_{ox,na}$ for the surface area measurement of Ti specimen. $1/C_{ox,na}$ and $1/C_{ox,an}$ appeared to be linearly proportional to OCP and applied potential ($E_{app}$), with proportional constants of 0.086 and 0.051 $uF^{-1}\;V^{-1}$, respectively. The $C_{ox,na}$ also appeared to be linearly proportional to geometric surface area of the mechanically polished CP-Ti fixture specimen, with proportional constants of 11.3 and $8.5{\mu}F\;cm^{-2}$ at -0.45 $V_{Ag/AgCl}$ and -0.25 $V_{Ag/AgCl}$ of OCPs, respectively, in 0.1 M NaOH solution. This linear relationship between $C_{ox,na}$ and surface area is suggested to be applicable for the measurement of real surface area of Ti specimen.

• Journal of the Korean Chemical Society
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• v.16 no.3
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• pp.178-188
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• 1972

Diethyl itaconate was found to react tetrafluoroethylene, trifluorochloroethylene, and 1,1-difluoro-2,2-dichloroethylene quite rendily at $180^{\circ}C$ to form 1-carboxy-2,2,3,3,-tetrahalo-cyclobutane ethanoic acid derivatives ${C{\underline{X_2-CF_2-CH_2-}}C-(COOEt)-CH_2COOEt$, where X is Cl or F). Diethylcitraconate failed to yeild any cycloaddition products. The Physical and Chemical properties of the above esters and their dericatives are characterized and compared with other similar ring compounds.

• Korean Journal of Crystallography
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• v.9 no.1
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• pp.6-10
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• 1998

The complex[Cu(L)](ClO4)2 (1) (L:3,5,10,12-Tetramethyl-1,4,8,11-tetraazacyclotetradecane) has been synthesized and structurally characterized. The complex 1 crystallizes in the monoclinic system, space group P21/n with cell parameters a=8.208(2)Å, b=13.339(6) Å, c=10.752(5) Å, β=111.02(4)˚ Z=2. Least-squares refinement of 1 led to a R(RW)factor of 0.073 (0.142) for 617 observed reflections of F0>40(F0). The crystal structure of 1 has a square-planar geometry and adopts the trans-III conformation.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.2
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• pp.117-124
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• 2017

Densities of molten salt mixtures of eutectic LiCl-KCl with $UCl_3$, $CeCl_3$, or $LaCl_3$ at various concentrations (up to 13 wt%) were measured using a liquid surface displacement probe. Linear relationships between the mixture density and the concentration of the added salt were observed. For $LaCl_3$ and $CeCl_3$, the measured densities were significantly higher than those previously reported from Archimedes' method. In the case of $LiCl-KCl-UCl_3$, the data fit the ideal mixture density model very well. For the other salts, the measured densities exceeded the ideal model prediction by about 2%.

• Korean Journal of Microbiology
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• v.31 no.4
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• pp.318-325
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• 1993

The optima] conditions for the formation, the regeneration. and the spheroplast fusion of Flavimonas aryz/habitans spheroplasts were investigated. Cells were transformed to spherop]asts effectively by treatment of 0.5% volume (v/v) of 0.] M EDTA and ]00 flg/ml lysozyme at $37^{\circ}C$ for 30 min without shaking. Magnesium chloride and calcium chloride were effective on the stabilization of spheroplasts. and 20 mM calcium chloride in the rich regeneration medium improve the yield of regenerants as much as 3.5-fo]d. Addition of 0.8% bovine serium albumine (BSA) in dilution buffer for spheroplast formation improved the stabilization of spheroplasts over extended periods (4-6 hr) at room temperature. and thus increased the yield of recombinants to 4.5-fold. The spheroplast formation frequency and regeneration frequency of F aryzihabitans strain was 90.10% and 3.800/." respectively. The first regenerated cell of F. aryzihabitans spheroplasts were appeared 6 hours after plating. By I I hours after plating, 80% of spheroplasts were regenerated on thc rich regeneration medium containing 0.5 M sucrose. The intraspeci11c spheroplast fusion of F urvz/habitans was carried out and the properties of obtained fusants were investigated. Formation of fusion products was effective when the Flav/munas spheroplast mixture was treated with 40%(w/v) PEG6000 and 20 mM CaCl, for 10 min at room temperature. and thc formation of frequency of recombinants were $2.0{\times}10^{-5}~3.6{\times}10^{-5}$. All tested recombinant clones were very stable on further propagation.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.641-646
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• 2012

We used the hybrid density-functional (B3LYP/6-31G(d,p)) method to analyze the substitution patterns of $C_{20}H_{18}X_2$ derivatives (X = F, Cl, Br, or OH) obtained as disubstituted $C_{20}H_{20}$ cages. Our results suggest that the cis-1 regioisomers (1,2-dihalo derivatives) are less stable than the trans-1 regioisomers (1,20-dihalo derivatives), whereas in the case of the dihydroxy derivatives, the cis-1 regioisomer is more stable than the trans-1 regioisomer. This implies that in the dihalo-induced strain cages of $C_{20}H_{18}X_2$, the strain effect would affect the relative energies, while in the dihydroxide, the hydrogen bonds have a stronger effect on the relative energies in cis-1 regioisomer than the strain effect do. Thus this supports the experimental result in which the bisvicinal tetrol was of particular preparative-synthetic interest as a substitute for the lacking bisvicinal tetrabromide. Further, the topologies of the HOMO and LUMO characteristics of all $C_{20}H_{18}Cl_2$ and $C_{20}H_{18}Br_2$ regioisomers with the same symmetry are same, but they are different from those of $C_{20}H_{18}F_2$ and $C_{20}H_{18}(OH)_2$. This indicates that the five regioisomers of each $C_{20}H_{20}$ disubstituted derivative will have an entirely different set of characteristic chemical reactions.

• 한국포장학회:학술대회논문집
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• 2006.11a
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• pp.95-101
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• 2006

거창사과원예협동조합에서 구입한 사과 600상자를 5% $CaCl_2$ 용액에 각각 15분간 침지하는 방법으로 전처리 후 24시간 건조시키고 무포장구, $25{\mu}m$ 두께의 기능성 MA 필름으로 포장한 포장구와 무처리 무포장구인 대조구로 나누어 $0^{\circ}C$의 저온저장고로 옮겨 7개월 동안 저장하면서 3주 간격으로 품질을 분석하였다. 저장 기간이 증가할수록 중량 감소율은 Control 구보다 $CaCl_2$구와 $CaCl_2+MA$구의 중량 감소율이 월등히 낮았다. 경도변화는 저장 기간이 증가할수록 감소하는 경향을 보였으며, 그 중 $CaCl_2$구는 초기치 0.97 $kg_f$에서 저장 18주에는 0.95 $kg_f$로 초기치에 비해 2%의 가장 적은 변화를 보였다. 산도는 대조구보다 처리구의 산도가 높게 나타났으나 큰 차이는 나타나지 않았다. 가용성 고형분 함량은 저장 기간 모든 실험구에 따른 큰 차이가 없었다. 비타민 C 함량은 저장기간이 지날수록 모든 실험구에서 감소하는 경향을 보였으며, 기호도 조사에서 $CaCl_2$구와 $CaCl_2+MA$구가 대조구보다 유의적으로 높게 나타났다.

• Bulletin of the Korean Chemical Society
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• v.19 no.9
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• pp.947-951
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• 1998

$K_2NiF_4$-type layered compounds of the ($C_nH_{2n+1}NH_3)_2SnCl_4$ (n=2, 4, 6, 8, and 10) system have been synthesized from a stoichiometric mixture of $SnCl_2$ and alkyl ammonium salt using a low temperature solution technique under the inert atmosphere condition. Their crystal structures are assigned to the orthorhombic system by X-ray powder diffraction analysis. The a and b cell parameters show small changes. However, the c parameter is varied significantly according to the increment of alkyl chains of the organic layer which is located between inorganic layers in the compounds. The conformational phase transitions of the compounds are studied by the DSC in the temperature range of 300 to 500 K. FT-IR and Raman spectra are analyzed in the ranges of 1300 to 4000 cm-1 and of 50 to 360 $cm^{-1}$ with Ar-laser (λ=514.5 nm) excitation, respectively. Photoluminescence phenomena are observed for some compounds. The bond-length of Sn-Cl is determined by the EXAFS spectroscopic analysis.