• Title/Summary/Keyword: L2

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Synthesis and Solution Chemistry of Metal Hydrides from Cationic Rhodium(I) Catalyst Precursors [(L-L)Rh(NBD)]$ClO_4 (L-L=Fe({\eta}^5-C_5H_4PBu^t\;_2)_2,\;Fe{\eta}^5-C_5H_4PPhBu^t)_2)$

  • Tae-Jeong Kim
    • Bulletin of the Korean Chemical Society
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    • v.11 no.2
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    • pp.134-139
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    • 1990
  • The hydrogenation catalyst precursors $[(L-L)Rh(NBD)]ClO_4\;(L-L=Fe({\eta}^5-C_5H_4PBu^t\;_2)_2,\;Fe({\eta}^5-C_5H_4PPhBu^t)_2$; NBD = norbornadiene) react with $H_2(1\;atm,\;30^{\circ}C$, MeOH) to yield $[(L-L)HRh({\mu}-H)_3RhH(L-L)]ClO_4$. These hydrido species are fluxional, and variable temperature NMR studies show the existence of a number of equilibria involving both fluxional and non-fluxional species. The synthesis, solution structures, and fluxional behaviors of these hydrides are described.

The Analysis of Algorithm for L1/L2 Dual - Band GPS Receiver (L1/L2 듀얼 밴드 GPS 수신기의 상위 레벨 분석)

  • 김진복;송호준
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 1999.05a
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    • pp.78-81
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    • 1999
  • The position and time errors of a conventional L1-band GPS receiver (1575.42MHz) are known to be about 100 m and 70 ns, respectively. These errors are mainly due to the propagation delay of GPS satellite signals through ionosphere. Various L1/L2 dual-band GPS receivers are normally used to compensate for those position and time errors by detecting an accurate propagation delay. These receivers detect the propagation delay difference between the L1 and L2 signals based on the fact that the propagation delay through ionosphere is dependent on frequency and, from which, calculate an accurate propagation delay of the GPS signals through ionosphere. In this paper, we analyzed the architecture of a L1/L2 dual-band CPS receiver by high-level simulations with Synopsys's COSSAP Tool.

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An Efficient Implementation of Hybrid $l^1/l^2$ Norm IRLS Method as a Robust Inversion (강인한 역산으로서의 하이브리드 $l^1/l^2$ norm IRLS 방법의 효율적 구현기법)

  • Ji, Jun
    • Geophysics and Geophysical Exploration
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    • v.10 no.2
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    • pp.124-130
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    • 2007
  • Least squares ($l^2$ norm) solutions of seismic inversion tend to be very sensitive to data points with large errors. The $l^1$ norm minimization gives more robust solutions, but usually with higher computational cost. Iteratively reweighted least squares (IRLS) method gives efficient approximate solutions of these $l^1$ norm problems. I propose an efficient implementation of the IRLS method for a hybrid $l^1/l^2$ minimization problem that behaves as $l^2$ norm fit for small residual and $l^1$ norm fit for large residuals. The proposed algorithm shows more robust characteristics to the decision of the threshold value than the l1 norm IRLS inversion does with respect to the threshold value to avoid singularity.

Preparation and Crystal Structures of Silver(I), Mercury(II), and Lead(II) Complexes of Oxathia-Tribenzo-Macrocycles

  • Siewe, Arlette Deukam;Ju, Huiyeong;Lee, Shim Sung
    • Bulletin of the Korean Chemical Society
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    • v.34 no.3
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    • pp.725-730
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    • 2013
  • An investigation of the coordination behavior of sulfur-containing mixed-donor tribenzo-macrocycles $L^1-L^3$ ($L^1$: 20-membered $O_3S_2$, $L^2$: 20-membered $O_2S_3$, and $L^3$: 23-membered $O_4S_2$) with $d^{10}$-metal ($Ag^+$, $Hg^{2+}$, and $Pb^{2+}$) salts is reported. The X-ray structures of five complexes (1-5) with different structural types and stoichiometries, including mono- to dinuclear species have been determined. Reactions of $L^2$ and $L^3$ with the silver(I) salts ($PF_6{^-}$ and $SCN^-$) afforded two dinuclear 2:2 (metal-to-ligand) complexes with different arrangements: a sandwich-type cyclic dinuclear complex $[Ag_2(L^2)_2](PF_6)_2{\cdot}3CH_2Cl_2$ (1) and a linear dinuclear complex $[Ag_2(L^3)_2(SCN)_2]$ (2), in which two monosilver(I) complex units are linked by an Ag-Ag contact. Reactions of $L^1$ and $L^2$ with mercury(II) salts ($SCN^-$ and $Cl^-$) gave a mononuclear 1:1 complexes $[Hg(L^1)(SCN)_2]$ (3) and $[Hg(L^2)Cl_2]$ (4) with anion coordination in both cases. $L^2$ reacts with lead(II) perchlorate to yield a mononuclear sandwich-type complex $[Pb(L^2)_2(ClO_4)_2]$ (5), giving an overall metal coordination geometry of eight with a square antiprism arrangement. From these results, the effects of the donor variation and the anioncoordination ability on the resulting topologies of the soft metal complexes are discussed.

BCL2L10 Protein Induces Apoptosis in KGN-Human Granulosa Cells (KGN(난소과립세포)에서 BCL2L10 단백질의 세포사멸 유도 기능 연구)

  • Kim, Jae-Hong;Lee, Kyung-Ah;Bae, Jee-Hyeon
    • Development and Reproduction
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    • v.15 no.2
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    • pp.113-120
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    • 2011
  • BCL-2 family essential proteins to play a pivotal role to perform in apoptosis signaling pathways and essential proteins for the regulation of cell death. BCL2L10 protein is a member of BCL-2 family and it regulates both anti-apoptotic and pro-apoptotic function of specific tissue or cell line. BCL2L10 of function and expression is not reported in ovary cell lines. In this study we reported that BCL2L10 were significant expression of KGN cell line. Ectopic expression of BCL2L10 induced cell death, and its cells killing effect was blocked by pan-caspase inhibitor of the Z-VAD-fmk. Ectopic expression of BCL2L10 protein led to the activation of caspase 9 and caspase 3, suggesting apoptotic cell death, and confocal microscopic analyses showed that BCL2L10 was partially localized in mitochondria. Thus, we provide a novel function of BCL2L10 in KGN cells, which was involved in the intrinsic cell death pathway.

Water Quality of Some Spring Waters in Pusan Area (부산시내에 산재하는 몇몇 약수터 약수의 수질)

  • KIM Yong-Gwan;CHO Hyeon-Seo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.18 no.6
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    • pp.538-544
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    • 1985
  • This study was carried cut to evaluate the water quality of spring waters in Pusan area(see Fig. 1). In this experiment, twenty-five water samples were collected from 5 stations from December 1983 to August 1984. Range and mean values of constituents of the samples are as follows: pH $5.80{\sim}7.25$, 6.60; water temperature $6.0{\sim}23.0^{\circ}C,\;12.9^{\circ}C$; total residue $33.0{\sim}325mg/l$, 121.2mg/l; alkalinity $4.75{\sim}51.6mg/l$, 24.1mg/l; hardness $9.47{\sim}85.0mg/l$, 30.3mg/l; electrical conductivity $0.495{\sim}2.750{\times}^2{mu}{\mho}/cm,\;1.239{\times}10^2{\mu}{\mho}/cm$;turbidity $0.54{\sim}7.80$NTU, 2.04NTU; $KMnO_4$ consumed $0.51{\sim}8.47mg/l$, 1.96mg/l; chloride ion $4.91{\sim}36.0mg/l$, 12.55mg/l; fluoride ion ND-0.30ppm, 0.08ppm; nitrate-nitrogen ND-8.94mg/l, 1.94m:g/l; nitrite-nirogen ND-0.10mg/l, 0.03mg/l; ammonia-nitrogen ND-0.16mg/l, 0.03mg/l: phosphate-phosphorus ND-0.09mg/l, 0.03mg/l; silicate-silicious $0.42{\sim}22.7ng/l$, 7.96mg/l; copper ND-10.5ppb, 2.46ppb; lead ND-22.7ppb, 3.54ppb; zinc ND-103ppb, 21.33ppb; iron $20.3{\sim}2,800ppb$, 801.72ppb, respectively. Arsenic, cyan, cadmium, manganese, mercury, chrome and phenol were not detected. Total residue, electrical conductivity, turbidity and chloride ion of station 1 (Milrakdong) were higher than others as 178.1mg/l, $2.127{\times}10^2{\mu}{\mho}/cm$, 3.16NTU and 16.32mg/l. The concentration of silicious had a great influence on precipitation. The concentration of fluoride ion of spring waters was lower as 0.08ppm than the criterion for drinking water as 1ppm, while iron was exceed 2.7 times as 801.72ppb.

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Template Synthesis and Characterization of Four- and Five-Coordinate Copper(II) Complexes with Hexaaza Macrotricyclic Ligands 1,3,6,9,11,14-Hexaazatricyclo $[12.2.1.1^{6,9}]octadecane(L_1)$ and 1,3,6,10,12,15-Hexaazatricyclo $[13.3.1.1^{6,10}]eicosane(L_1)$

  • Myunghyun Paik Suh;Shin-Geol Kang;Teak-Mo Chung
    • Bulletin of the Korean Chemical Society
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    • v.11 no.3
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    • pp.206-208
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    • 1990
  • Cu(II) hexaazamacrotricyclic complexes $[Cu(L)](ClO_4)_2$ and $[(Cu(L)Cl]ClO_4$, where L = 1,3,6,9,11,14-hexaazatricyclo$[12.2.1.1^{6,9}]octadecane(L_1)$ or 1,3,6,10,12,15-hexaazatricyclo$[13.3.1.1^{6,10}]eicosane(L_2)$, have been prepared by the simple template condensation reactions of triamines, diethylenetriamine for $L_1$, and N-(2-aminoethyl)-1,3-propanediamine for $L_2$, with formaldehyde in the presence of $Cu(OAc)_2\;or\;CuCl_2$. The Cu(II) complexes of $L_1$ contain two 1,3-diazacyclopentane ring moieties and those of $L_2$ contain two 1,3-diazacyclohexane ring moieties that are fused to the 14-membered macrocyclic framework. Spectra indicate that complexes $[Cu(L)](ClO_4)_2\;and\;[Cu(L)Cl]ClO_4$ have square-planar and square-pyramidal chromophores, respectively. square-planar $[Cu(L)](ClO_4)_2$ are remarkably stable against ligand dissociation in acidic aqueous solutions. Square-pyramidal $[Cu(L)Cl]ClO_4$ complexes dissociate their axial Cl-ligands easily in aqueous solutions to form $[Cu(L)H_2O]^{2+}$ species. Infrared and UV/vis absorption spectra of the Cu(II) complexes reveal that Cu-N interactions and the ligand field strengths are significantly weaker in the complexes of $L_2$ than in the complexes of $L_1$.

AN INVESTIGATION ON GEOMETRIC PROPERTIES OF ANALYTIC FUNCTIONS WITH POSITIVE AND NEGATIVE COEFFICIENTS EXPRESSED BY HYPERGEOMETRIC FUNCTIONS

  • Akyar, Alaattin;Mert, Oya;Yildiz, Ismet
    • Honam Mathematical Journal
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    • v.44 no.1
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    • pp.135-145
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    • 2022
  • This paper aims to investigate characterizations on parameters k1, k2, k3, k4, k5, l1, l2, l3, and l4 to find relation between the class of 𝓗(k, l, m, n, o) hypergeometric functions defined by $$5_F_4\[{\array{k_1,\;k_2,\;k_3,\;k_4,\;k_5\\l_1,\;l_2,\;l_3,\;l_4}}\;:\;z\]=\sum\limits_{n=2}^{\infty}\frac{(k_1)_n(k_2)_n(k_3)_n(k_4)_n(k_5)_n}{(l_1)_n(l_2)_n(l_3)_n(l_4)_n(1)_n}z^n$$. We need to find k, l, m and n that lead to the necessary and sufficient condition for the function zF([W]), G = z(2 - F([W])) and $H_1[W]=z^2{\frac{d}{dz}}(ln(z)-h(z))$ to be in 𝓢*(2-r), r is a positive integer in the open unit disc 𝒟 = {z : |z| < 1, z ∈ ℂ} with $$h(z)=\sum\limits_{n=0}^{\infty}\frac{(k)_n(l)_n(m)_n(n)_n(1+\frac{k}{2})_n}{(\frac{k}{2})_n(1+k-l)_n(1+k-m)_n(1+k-n)_nn(1)_n}z^n$$ and $$[W]=\[{\array{k,\;1+{\frac{k}{2}},\;l,\;m,\;n\\{\frac{k}{2}},\;1+k-l,\;1+k-m,\;1+k-n}}\;:\;z\]$$.

Effect of Plant Growth Regulators on Plant Regeneration from Leaf and Stem Explant Cultures of Sedum erythrostichum Miq. (꿩의비름(Sedum erythrostichum Miq.)의 잎과 줄기 절편으로부터 식물체의 재분화에 미치는 생장조절제의 영향)

  • 윤의수
    • Korean Journal of Plant Tissue Culture
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    • v.24 no.5
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    • pp.285-289
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    • 1997
  • Leaf and stem explants of Sedum erythrostichum Miq. were cultured on MS medium supplemented with various combinations of growth regulators. After two weeks of culture, 100% of the leaf explants formed calli on medium containing 2.0 mg/L 2, 4-D and 1.0 mg/L BA. Callus proliferated when subcultured on medium containing 2.0 mg/L 2, 4-D and 1.0 mg/L BA. Numerous adventitious buds were regenerated from callus cultured on the medium containing 2.0 mg/L NAA and 1.0 mg/L BA. Root formation from shoot was occurred on the MS basal medium containing 1.0 mg/L IAA.

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Effect of Growth Regulators, Carbon Sources and Silver Nitrate on Callus Formation and Plant Regeneration of Turf Grass (잔디의 캘러스 형성 및 재분화에 끼치는 식물생장조절제, 탄소원 및 AgNO3의 영향)

  • Han, S.S.;Rim, Y.S.;Jeong, J.H.
    • Korean Journal of Weed Science
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    • v.16 no.3
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    • pp.221-229
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    • 1996
  • This study was carried out to determine the effects of growth regulators, carbon sources and silver nitrate on callus formation and plant regeneration of turfgrass. The results were summarized as fallows : Callus from Korean lawngrass (Zoysia japonica Steud.) and pencross creeping bentgrass (Agrostis palustrir Huds.) induced better in MS medium than in N6 medium and by addition of 2,4-D than by that of NAA. Callus formation from Korean lawngrass and penncross creeping bentgrass was very effective at MS medium adding 1mg/L 2,4-D and at the medium adding 2mg/L 2,4-D, repectively. Growth of callus was good at MS medium containing 2mg/L 2,4-D+0.2mg/L NAA. Callus growth of Korean lawngrass and penncross creeping bentgrass was good when kinetin was added 0.2mg/L and 0.3mg/L, individually, to MS medium containg 2mg/L 2,4-D+0.2mg/L NAA. Regeneration rate from leaf and stock callus of Korean lawngrass was 44% at MS medium adding 2,4-D 2mg/L+NAA 0.2mg/L+kinetin 0.3mg/L and 32% at the medium containing 2,4-D 2mg/L+NAA 0.2mg/L+kinetin 0.3mg/L, each and that from leaf and stock callus of penncross creeping bentgrass was 80% and 67%, each, at the medium adding 2,4-D 2mg/l+NAA 0.2mg/L+kinetin 0.3mg/L. Regeneration rate of Korean lawngrass and penneross creeping bentgrass increased by 3 to 4% and by 10 to 16%, respectively, when added $AgNO_3$ 1~2mg/L to the above-mentioned regeneration medium.

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