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Synthesis and Characterization of New Mono-N-functionalized Tetraaza Macrocyclic Nickel(II) and Copper(II) Complexes

  • Kim, Hyun-Ja;Kang, Shin-Geol
    • Bulletin of the Korean Chemical Society
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    • v.32 no.8
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    • pp.2565-2570
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    • 2011
  • The reaction of bromoacetonitrile with 3,14-dimethyl-2,6,13,17-tetraazatetracyclo[$16.4.1^{2.6}.0^{1.18}.0^{7.12}$]tricosane ($L^{10}$) containing a N-$CH_2$-N linkage produces 17-cyanomethyl-3,14-dimethyl-2,6,13,17-tetraazatetracyclo-[$16.4.1^{2.6}.0^{1.18}.0^{7.12}$]tricosane ($L^{11}$). The mono-N-functionalized macrocyclic complexes $[ML^2]^{2+}$ (M = Ni(II) or Cu(II); $L^2$ = 2-cyanomethyl-5,16-dimethyl-2,6,13,17-tetraazatricyclo[$16.4.0.0^{7.12}$]docosane) can be prepared by the reaction of $L^{11}$ with nickel(II) or copper(II) ion in acetonitrile. The N-$CH_2CN$ group attached to $[ML^2]^{2+}$ readily reacts with water or methanol to yield the corresponding complexes of $HL^3$ bearing one N-$CH_2CONH_2$ pendant arm or $L^4$ bearing one $N-CH_2C(=NH)OCH_3$ group. The $N-CH_2CONH_2$ or $N-CH_2C(=NH)OCH_3$ group of each complex is coordinated to the central metal ion. Both $[NiL^4(H_2O)]^{2+}$ and $[CuL^4]^{2+}$ are quite stable in acidic aqueous solutions, but undergo hydrolysis to yield $[Ni(HL^3)(H_2O)]^{2+}$ or $[Cu(HL^3)]^{2+}$ in basic aqueous solutions. In contrast to $[Cu(HL^3)]^{2+}$, $[Ni(HL^3) (H_2O)]^{2+}$ is readily deprotonated to form $[NiL^3 (H_2O)]^+$ ($L^3$ = a deprotonated form of $HL^3$) in basic aqueous solutions.

Success Factors of O2O(Online-to-Offline) Commerce (O2O(Online-to-Offline) 상거래의 성공요인)

  • Kim, JaeKyung;Jang, YuRi;Jeong, HyeJin;Moon, Yun Ji
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.10a
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    • pp.374-377
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    • 2015
  • O2O(Online-to-offline) service is the new commerce system form that mixed information search and payment of products and services from online and receipt of goods from offline. O2O commerce combine advantage of existing electronic commerce and redeem the critical point of each commerce circulation method, but earnings model is still lacking compared to development speed of O2O technology. Therefore this study drew common factor applied to O2O service to search success factor of O2O commerce on the point of view as a customer Centered by existing B2C electronic commerce, Mobile commerce, and service quality model of offline commerce included O2O commerce method. Further we suggest O2O success factor model combined new O2O success factor additionally reflecting qualitative research result based on drew O2O success service Quality factor.

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Refractive-index Prediction for High-refractive-index Optical Glasses Based on the B2O3-La2O3-Ta2O5-SiO2 System Using Machine Learning

  • Seok Jin Hong;Jung Hee Lee;Devarajulu Gelija;Woon Jin Chung
    • Current Optics and Photonics
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    • v.8 no.3
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    • pp.230-238
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    • 2024
  • The refractive index is a key material-design parameter, especially for high-refractive-index glasses, which are used for precision optics and devices. Increased demand for high-precision optical lenses produced by the glass-mold-press (GMP) process has spurred extensive studies of proper glass materials. B2O3, SiO2, and multiple heavy-metal oxides such as Ta2O5, Nb2O5, La2O3, and Gd2O3 mostly compose the high-refractive-index glasses for GMP. However, due to many oxides including up to 10 components, it is hard to predict the refractivity solely from the composition of the glass. In this study, the refractive index of optical glasses based on the B2O3-La2O3-Ta2O5-SiO2 system is predicted using machine learning (ML) and compared to experimental data. A dataset comprising up to 271 glasses with 10 components is collected and used for training. Various ML algorithms (linear-regression, Bayesian-ridge-regression, nearest-neighbor, and random-forest models) are employed to train the data. Along with composition, the polarizability and density of the glasses are also considered independent parameters to predict the refractive index. After obtaining the best-fitting model by R2 value, the trained model is examined alongside the experimentally obtained refractive indices of B2O3-La2O3-Ta2O5-SiO2 quaternary glasses.

1,4-Dicyanobutene Bridged Binuclear Iridium (I, III) Complexes and Their Catalytic Activities

  • Park, Hwa-Kun;Chin, Chong-Shik
    • Bulletin of the Korean Chemical Society
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    • v.8 no.3
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    • pp.185-189
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    • 1987
  • Reactions of $Ir(ClO)_4(CO)(PPh_3)_2$ with dicyano olefins, cis-NCCH = CH$CH_2$$CH_2$CN (cDC1B), trans-NCCH = CH$CH_2$$CH_2$CN (tDC1B), trans-NC$CH_2$CH = CH$CH_2$CN (tDC2B), and NC$CH_2$$CH_2$$CH_2$$CH_2$CN (DCB) produce binuclear dicationic iridium (I) complexes, $[(CO)(PPh_3)_2Ir-NC-A-CN-Ir(PPh_3)_2(CO)](ClO_4)_2$ (NC-A-CN = cDC1B (1a), tDC1B (1b), tDC2B (1c), DCB (1d)). Complexes 1a-1d react with hydrogen to give binuclear dicationic tetrahydrido iridium (Ⅲ ) complexes, $[(CO)(PPh_3)_2(H)_2Ir-NC-A-CN-Ir(H)_2(PPh_3)_2(CO)](ClO_4)_2$ (NC-A-CN = cDC1B (2a), tDC1B (2b), tDC2B (2c), DCB (2d)). Complexes 2a and 2b catalyze the hydrogenation of cDC1B and tDC1B, respectively to give DCB, while the complex 2c is catalytically active for the isomerization of tDC2B to give cDC1B and tDC1B and the hydrogenation of tDC2B to give DCB at $100^{\circ}C$.

Upregulation of smpd3 via BMP2 stimulation and Runx2

  • Chae, Young-Mi;Heo, Sun-Hee;Kim, Jae-Young;Lee, Jae-Mok;Ryoo, Hyun-Mo;Cho, Je-Yoel
    • BMB Reports
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    • v.42 no.2
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    • pp.86-90
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    • 2009
  • Deletion of smpd3 induces osteogenesis and dentinogenesis imperfecta in mice. smpd3 is highly elevated in the parietal bones of developing mouse calvaria, but not in sutural mesenchymes. Here, we examine the mechanism of smpd3 regulation, which involves BMP2 stimulation of Runx2. smpd3 mRNA expression increased in response to BMP2 treatment and Runx2 transfection in C2C12 cells. The Runx2-responsive element (RRE) encoded within the -562 to -557 region is important for activation of the smpd3 promoter by Runx2. Electrophoretic mobility shift assays revealed that Runx2 binds strongly to the -355 to -350 RRE and less strongly to the -562 to -557 site. Thus, the smpd3 promoter is activated by BMP2 and is directly regulated by the Runx2 transcription factor. This novel description of smpd3 regulation will aid further studies of bone development and osteogenesis.

SERO-EPIDEMIOLOGICAL STUDY OF BRUCELLOSIS AMONG GOATS AND SHEEP AT PESHAWAR DISTRICT

  • Ghani, M.;Siraj, M.;Zeb, A.;Naeem, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.5
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    • pp.489-494
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    • 1995
  • Sero-epidemiological study was carried out to observe the prevalence of brucellosis in 500 slaughtered as well as in 500 healthy animals in Peshawar district of N.W.F.P. All serum samples were subjected to four serological tests i.e. Standard Plate Test (SPT), Standard Tube Test (STT), Rivanol Test (RV) and 2, Mercapto-Ethanol Test (2, ME). The incidence of disease in 500 healthy animals tested by standard plate test, standard tube test, rivanol test and 2, Mercapto-ethanol test, was 2.8%, 1.8%, 1.6% and 1.2% respectively. While the incidence of brucellosis in 500 slaughter animals from Peshawar abattoir was 3.0%, 2.2%, 2.00% and 1.2% by standard plate test, standard tube test, rivanol test and 2, Mercapto-ethanol test The disease prevalence was higher in slaughtered animals as compared to healthy animals. The disease was more common in goats than sheep, also more prevalence in aged female than younger stocks. The efficacy of SPT was found more effective as compared to STT, RV, and 2, ME tests both in slaughtered as well as apparently healthy animals at Peshawar district. Standard Plate test detected 2.9%, Standard Tube test 2.0%, Rivanol test 1.8% and 2, Mercapto-ethanol test detected 1.2% positive cases in slaughtered as well as in healthy animals. So the Standard Plate Test was found to be more reliable, sensitive, and easy to performed.

Synthesis of (${\pm}$)-cis-8-amino-l-2,3,4,4a,5,10b-hexahydrothiazolo[4,5-f]indeno [1,2-b][1,4]oxazine ((${\pm}$)-cis-8-Amino-2,3,4,4a,5,10b-hexahydrothiazolo[4,5-f]indeno [1,2-b][1,4]oxazine의 합성)

  • Ma, Eun-Sook
    • YAKHAK HOEJI
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    • v.52 no.6
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    • pp.488-493
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    • 2008
  • 2-Aminothiazole ring as a bioisoster of catechol in dopamine has provided with good oral availability and lipophilic property. 2-Aminoindan, is a rigid form of dopamine, was evaluated as a dopamine D3 agonist with low neurotoxicity. Dopamine D3 agonist was evaluated as selective for the treatment of Parkinson's disease. In order to develop a novel dopamine D3 agonist, we tried to synthesize the aminothiazoloindenoxazine derivative that is a hybrid structure of aminoindenoxazine and thiazole ring. cis-2-Amino-1-indanol (2) was synthesized from 1,2-indandione-2-oxime by catalytic hydrogenation and it was treated with chloroacetyl chloride and NaH in benzene solution to give (${\pm}$)-cis-4,4a,5,9b-tetrahydroindeno[1,2-b][1,4]oxazin-3(2H)-one (6). Nitration of 6 by the mixed acid gave 8-nitro compound (7) and the carbonyl group of 7 was reduced with $LiAlH_4$ to afford compound (8). 8 was reduced to form (${\pm}$)-cis-8-amino-2,3,4,4a,5,9b-hexahydroindeno[1,2-b][1,4]oxazine (9) and finally it was cyclized with KSCN in glacial acetic acid to yield (${\pm}$)-cis-8-amino-2,3,4,4a,5,10b-hexahydrothiazolo[4,5-f]indeno[1,2-b][1,4]oxazine (10).

Cadmium-Induced Phytotoxicity in Tomato Seedlings Due to the Accumulation of H2O2 That Results from the Reduced Activities of H2O2 Detoxifying Enzymes

  • Cho, Un-Haing
    • The Korean Journal of Ecology
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    • v.27 no.2
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    • pp.107-114
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    • 2004
  • Tomato (Lycopersicon esculentum) seedlings exposed to various concentrations of $CdC1_2$ (0∼100 $\mu$M) in the nutrient solution for up to 9 days were analyzed with the seedling growth, $H_2O_2$ production, glutathione levels and activity changes of enzymes related to $H_2O_2$ removal. The growth of seedlings was inhibited with over 50 $\mu$M Cd, whereas the levels of $H_2O_2$ and glutathione were enhanced with Cd exposure level and time. Meanwhile, Cd exposure increased the activities of catalase (CAT) and glutathione reductase (GR) but decreased the activities of dehydroascorbate acid reductase (DHAR) and ascorbate peroxidase (APX) in both leaves and roots. These results suggest that the altered activities of antioxidant enzymes particularly involved in the $H_2O_2$ removal and the subsequent $H_2O$$_2$ accumulation could induce the Cd-induced phytotoxicity.

Development of Pd/TiO2 Catalysts with La2O3 Addition and Study on the Performance Improvement of H2 Oxidation at Room Temperature (La2O3가 첨가된 Pd/TiO2 촉매의 개발 및 H2 상온산화 반응에서의 성능 향상 연구)

  • Lee, Dong Yoon;Kim, Sung Chul;Lee, Sang Moon;Kim, Sung Su
    • Applied Chemistry for Engineering
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    • v.31 no.6
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    • pp.674-678
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    • 2020
  • In this study, a Pd/TiO2 catalyst which oxidized H2 at room temperature without an additional energy source was prepared. And a specific surface area of TiO2 as a support was not proportional to H2 oxidation reaction performance of Pd/TiO2 catalyst. In addition La2O3 was added to Pd/TiO2 catalyst in order to evaluate the performance effect due to the change of catalysts physical properties. A Pd/La2O3-TiO2 was prepared by adding different amounts of La2O3 to TiO2 and CO chemisorption analysis was performed. Compared to the conversion rate (14% at 0.5% H2) of the Pd/TiO2(G) catalyst, the Pd/La2O3-TiO2 catalyst showed 74% which was improved by more than five times. It was found that the larger the metal dispersion of Pd as an active metal is, the more favorable to H2 oxidation reaction is. However, when the added La2O3 amount exceeded 10%, the catalyst performance decreased again. Finally, it was concluded that the physical properties of the Pd/La2O3-TiO2 catalyst have a dominant influence on the catalytic activity until 0.3~0.5% of injected H2 concentrations and the catalyst reaction rate was controlled by substance transfer from 1% or more concentrations of H2.

Comparison of Yield in Aiternating Crop System Mixed of Tillering Hybrid Corn and Soybean (분얼형(分蘖型) 옥수수 교잡종(交雜種)과 대두(大豆)의 교호작(交互作)에 대한 수량(收量) 비교(比較) 시험(試驗))

  • Lee, Hee Bong;Choe, Bong Ho;Lee, Won Koo;Park, Ki Sun;Choi, Chang Yeol
    • Korean Journal of Agricultural Science
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    • v.20 no.2
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    • pp.117-124
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    • 1993
  • This study was conducted to determine the effects of alternating planting systems of soybean and tillering hybrid corn on yield of both crops. The planting systems included monocultures of both crops. 1 to 1 row ratio, 1 to 2 row ratio, 1 to 3 row ratio, 2 to 1 row ratio, 2 to 3 row ratio, 3 to 1 row ratio, 3 to 2 row ratio and 3 to 3 row ratio of soybean and corn. The results obtained are summarized as follows : The plant height of soybean was increased as the number of planting rows of corn increased. But the plant, height of soybean was quite stabilized when the ratio of soybean planting rows increased. When the plant height of soybean was increased due to the increased row number of corn, the branch number and diameter of soybean decreased and lodging ratio increased. Total fresh weight of soybean per 10a was decreased as the ratio of soybean planting decreased and it was increased when the ratio of soybean planting increased over monoculture of soybean. Dry weight of soybean per 10a showed the same tendency of the fresh weight. But the highest grain yield of soybean was obtained in the monoculture of soybean and it was 276 kg/10a. Comparatively high yield of soybean was obtained in the systems of 2 to 1 and 3 to 3 ratios. The plant height, number of tillers and number of ears per plant of tillering corn were greatly affected by the alternating planting of soybean and they were 208.9cm, 2.1 and 4 per plant, respectively. The fresh and dry weights and yield of corn per 10a showed significant differences among systems. The average fresh and dry weight of corn in the systems of 3 to 1 and 2 to 1 were 1000 kg and 100 kg higher than those of monoculture of corn. The kernel yields of corn per 10a were 438 kg in the monoculture system and 530 kg in the systems of 3 to 2 and 2 to 1. The total fresh weights of corn and soybean in systems of 3 to 1, 3 to 2 and 2 to 1 were higher than 5721 kg of soybean and 4358 kg of corn in the monoculture. Combined dry weight was high in the order of monoculture, 2 to 1 and 3 to 1 row ratios. Combined grain yield was high in the systems of 2 to 1 and 3 to 1 row ratios and it was over 430 kg per 10a.

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