• Bulletin of the Korean Chemical Society
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• 제32권8호
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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.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 추계학술대회
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• pp.374-377
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• 2015

O2O(Online-to-offline) 서비스는 온라인에서의 제품 및 서비스 정보검색과 결제, 그리고 오프라인에서의 제품수령이 혼합된 새로운 상거래 방식의 한 형태이다. O2O 상거래는 기존 전자상거래의 장점과 오프라인 상거래의 장점을 결합하고, 각 상거래 유통방식의 한계점을 보완하지만, O2O 기술의 발전속도에 비해 수익모델이 아직까지는 부족한 것이 현실이다. 따라서 소비자 측면에서 O2O 상거래의 성공요인을 탐색하기 위해 본 연구는 O2O 상거래 방식에 포함된 기존 B2C 전자상거래, 모바일 상거래, 그리고 오프라인 상거래의 서비스품질모델(service quality model)을 중심으로 O2O에 적용될 공통 요인을 도출하였다. 나아가 도출된 O2O 성공 서비스 품질요인을 기반으로 질적연구 결과를 반영하여 새로운 O2O 서비스 성공요인이 추가적으로 결합된 O2O 성공요인 모형을 제안한다.

• Current Optics and Photonics
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• 제8권3호
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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.

• Bulletin of the Korean Chemical Society
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• 제8권3호
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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 $100^{\circ}C$.

• BMB Reports
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• 제42권2호
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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.

• Asian-Australasian Journal of Animal Sciences
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• 제8권5호
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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.

• 약학회지
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• 제52권6호
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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).

• The Korean Journal of Ecology
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• 제27권2호
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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.

• 공업화학
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• 제31권6호
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• pp.674-678
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• 2020

본 연구에서는 상온 조건에서 추가적인 에너지원 없이 H2 산화가 가능한 Pd/TiO2 촉매를 제조하였고, 지지체인 TiO2의 비표면적은 Pd/TiO2 촉매의 H2 산화 반응 성능과 비례하지는 않은 것을 확인하였다. 또한 촉매의 물성 변화에 의한 성능 영향 평가를 위하여 La2O3를 Pd/TiO2 촉매에 첨가하였다. La2O3를 TiO2에 함량별로 첨가하여 Pd/La2O3-TiO2를 제조하였고, CO chemisorption 분석을 진행하였다. Pd/TiO2(G) 촉매의 전환율(14% at 0.5% H2)과 비교하여 Pd/La2O3-TiO2 촉매가 74% 전환율로 5배 이상의 성능 증진이 나타났다. Pd/La2O3-TiO2 촉매는 활성금속인 Pd의 metal dispersion이 클수록 H2 산화반응에 유리한 것으로 분석되었다. 하지만 첨가되는 La2O3가 10%를 초과하게 되면 촉매 성능이 다시 감소하는 것을 알 수 있었다. 마지막으로 Pd/La2O3-TiO2 촉매의 물성이 지배적인 영향을 미치는 것은 주입되는 H2가 0.3~0.5% 농도 조건까지이며, 1% 이상의 H2 농도부터는 물질전달이 촉매 반응속도를 지배하는 것으로 판단된다.

• 농업과학연구
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• 제20권2호
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• pp.117-124
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• 1993

대두(大豆)와 분얼형(分蘖型) 옥수수의 상호간(相互間)에 생육의 안정성(安定性)을 도모하고 동시에 최대수량을 얻고자 파종비율을 달리한 교호작(交互作)으로 하여 생체(生體), 건물(乾物) 및 종실중(種實重)의 상호(相互) 비교(比較)를 통해 적정(適定) 파종비율(播種比率)을 구명하고자 실시한 결과는 다음과 같다. 1. 콩의 간장(桿長)은 단작(單作)의 경우 59.5cm 였는데 콩의 파종비율를 낮추고 옥수수의 비율을 증가 시킨 처리에서 크게 도장(徒長)되었으나 상대적으로 콩의 비율이 증가된 2:1, 3:1, 3:2, 3:3 처리에서는 비교적 콩의 초형(草型)이 단작형(單作型)으로 안정(安定)되었다. 2. 대부분 위와같이 도장된 처리구에서는 분지수(分枝數)와 경태(徑太)가 크게 감소되었고 도대율(倒代率)의 증가가 뚜렸한 현상을 보였다. 3. 10a당 생체중(生體重)은 콩의 비율이 옥수수에 비해 상대적으로 낮은 1:1, 1:2, 1:3 처리구가 단작에 비해 크게 감소 되었으나 콩의 비율을 증가 시킨 2:1, 2:3, 3:1, 3:2, 3:3 등에서는 오히려 단작(單作)보다 크게 증가 되었다. 4. 10a당 건물중(乾物重) 역시 같은 경향이었으나 10a당 종실수량의 경우에는 단작이 276kg으로 가장 높았고 2:1, 3:3처리구 역시 비교적 높게 나타났다. 5. 옥수수의 생육 특성을 보면 평균 간장(桿長)이 208.9cm, 주당(株當) 펑균 분얼수(分蘖數)는 2.1개, 주당(株當) 평균 이삭수(數)는 4.0개로 콩의 파종비율의 증감(增減)에서 다소의 변이(變異)를 보였으나 유의차(有意差)는 인정 되지 않았다. 6. 각 처리간 10a당 생체중, 건물중, 종실중은 다소의 유의차를 보였는데 생체중과 건물중은 3:1, 2:1처리구에서 단작보다 1000kg와 100kg정도가 각각 높았고 종실중은 모든 처리구에서 단작의 438kg보다 높았는데 특히 3:2, 2:1처리에서 530kg 정도로 높게 나타났다. 7. 두 공시 작물을 파종 비율에 따라 10a 당으로 환산(換算)한 총량(總量)을 보면 생체중의 경우 3:1, 3:2, 2:1처리에서 콩 단작의 5721kg이나 옥수수 단작의 4358kg 보다 높았고 건물중의 합은 옥수수 단작, 2:1, 3:1순으로 높았는데 종실중은 2:1, 3:1처리구에서 430kg 이상이었다.