In anion exchange membrane fuel cells, Pd nanoparticles are extensively studied as promising non-Pt catalysts due to their electronic structure similar to Pt. In this study, to fabricate Pd nanoparticles well dispersed on carbon support materials, we propose a synthetic strategy using mixed organic ligands with different chemical structures and functions. Simultaneously to control the Pd particle size and dispersion, a ligand mixture composed of oleylamine(OA) and trioctylphosphine(TOP) is utilized during thermal decomposition of Pd precursors. In the ligand mixture, OA serves mainly as a reducing agent rather than a stabilizer since TOP, which has a bulky structure, more strongly interacts with the Pd metal surface as a stabilizer compared to OA. The specific roles of OA and TOP in the Pd nanoparticle synthesis are studied according to the mixture composition, and the oxygen reduction reaction(ORR) activity and durability of highly-dispersed Pd nanocatalysts with different particles sizes are investigated. The results of this study confirm that the Pd nanocatalyst with large particles has high durability compared to the nanocatalyst with small Pd nanoparticles during the accelerated degradation tests although they initially indicated similar ORR performance.

단일막이 가지는 저유량 한계성과 복합막이 가지는 용질 역확산 현상을 완화하기 위한 방법으로 지지층 내 금속 착물이 균일하게 정착된 PSF 고분자 지지층을 제조하였다. 부직포의 두께와 밀도를 조절하였으며 지지층 제조법 최적화 이후 Fe(II)-chelate 착물을 포함하는 정삼투 분리막을 제조하였다. 지지층 제조방법에 있어 고분자의 부직포 함침 속도 조절이 정삼투 분리막 지지층의 구조결정에 가장 중요한 역할을 함을 볼 수 있었다. 고분자의 상 전이 과정에 있어서 금속 착물과 같은 극성물질의 존재가 용매 -비용매 치환 속도에 영향을 주어 지지층 구조 조절을 유도하였으며 그 결과, 용질 역확산이 약 0.07 - 0.11 GMH의 값을 가지는 높은 제거효율의 FO막을 제조할 수 있었다.

돼지 페르몬성 분자를 탐색하기 위하여 일련의 green odorant로서 기질 분자인 2-(cyclohexyloxy)tetrahydrofurane 유도체들의 정량적인 구조와 수용체인 porcine odorant binding protein (pOBP) 사이의 결합 친화력 상수(p(Od)50)에 대한 비교 분자 유사성 지수 분석(CoMSIA)을 실행하였다. 가장 양호한 CoMSIA 모델(I-AI)은 기질 분자내 입체 중심의 절대 배열이 I: C1'(R),C2(S)인 분자를 atom based fit 정렬하였을 경우의 입체장 조건에서 유도되었으며 PLS 분석 결과, 예측성이 r2cv.(q2)=0.856 그리고 적합성이 r2ncv.=0.964이었다. 모델의 CoMSIA 등고도 상, pOBP와 냄새 분자 사이의 상호작용으로부터 가장 높은 결합 친화력을 나타내는 분자의 구조적 특징들을 이해할 수 있었다.

생물학적 자극통제 수단으로 활용하기 위한 돼지 웅성 페르몬성 분자를 탐색하고자 일련의 냄새 분자로서 2-(cyclo-hexyloxy) tetrahydrofurane 유도체들의 정량적인 구조와 수용체인 porcine odorant binding protein (pOBP)간의 결합 친화력 상수(p(Od)50)에 대한 비교 분자장 분석(CoMFA)을 실행하였다. 가장 양호한 CoMFA 모델 AIV (r2 cv.(q2)=0.886 및 r2 ncv.=0.984)은 기질 분자 내 입체 중심(chiral center)의 절대 배열이 C1(R),C2(S)인 분자를 atom based fit 방법으로 배열하였을 경우의 standard field와 indicator field가 조합된 CoMFA장의 조건에서 유도되었다. 이 CoMFA 모델은 입체장 40.8% 정전기장 14.6%및 소수성장 44.6%가 결합 친화력 상수에 영향을 미치는 요소임을 나타내었다. 등고도의 분석 결과로부터 효과적인 결합 친화력 냄새 분자를 수식하는 데 몇 가지 가치 있는 정보를 얻을 수 있었다.

돼지 웅성 페르몬인 5a-androst-16-en-3-one을 대체할 수 있는 활성 분자를 탐색하여 가축의 생산과 수요를 조절하기 위한 생물학적 자극 통제 수단으로 활용하고자 냄새 분자로서 2-cyclohexyloxytetrahydrofurane (A) 및 2-phenoxytetrahydrofurane (B) 유도체들의 구조 변화와 수용체인 porcine odorant binding protein (pOBP)에 대한 결합친화력 상수(p[Od.]/sub 50/) 사이의 정량적인 구조-활성관계에 관한 분자 HQSAR 모델XI을 유도하였다. 냄새 분자 중에서 cyclohexyl-치환체(A)가 phenyl-치환체(B)보다 높은 결합 친화력을 나타내었으며(A>B) 모델XI은 분자 조각크기(5∼8), 홀로그램 길이(97 bin)의 키랄성(chirality)조건에서 예측성(q²=0.916)과 상관성(r²=0.988)이 매우 양호하였다. 기여도(contribution map)로부터 냄새 분자의 결합 친화력 상수에 기여하는 부분은 2-oxyfuryl group의 C3 및 C5 원자인 반면에 cyclohexyl 고리상 tert-butyl group의 중심 탄소 원자와 furyl group의 C4 원자 부분은 기여하지 않았다.

The metal complexes containing amino acidic ligands were prepared by using 11 kinds of amino acids as ligands and Ni, Cu, Co, Zn, Fe as a central metal. The starting was continued for 4hrs at room temperature. But Bis(D,L-Serine)Ni (II), and (D,L-Serine)Co (II) were prepared by heating method(80℃). In order to investigated reaction activity of Bis(D,L-Aspartato) Metal(II), stirring time was varied and Bis(D,L-Tyrosine ) Metal(II) used different divalent metal salts. We anticipate getting a great value from these prepared complexes as a monomer and a catalyst of polymerization which has peculier characteristics.

비정질 실리카겔은 Si와 O로 이루어진 가장 간단한 화합물로서, 표면에 다양한 구조의 물과 수산기, 그리고 합성과정에서 형성된 유기 리간드(ligand)를 함유하고 있어, 지권, 수권, 그리고 생물권의 상호작용을 이해하는 모델 시스템으로서 의미를 갖는다. 본 연구에서는 17O NMR 분광분석을 통해 비정질 실리카겔의 Si-O-Si와 Si-OH 산소 원자환경의 차이를 규명하고자 하였다. 이를 위해 SiCl4의 수화반응을 통해 17O이 집적된 비정질 실리카겔을 합성하였다. 1H과 29Si NMR 분광분석 결과, 비정질 실리카겔 표면에는 다양한 수소결합 세기를 가진 물과 수산기 이외에, Si-O·sR 형태의 유기 리간드가 존재함을 확인하였다. 이와 같은 유기 리간드는 에탄올 또는 증류수를 이용해 비정질 실리카겔을 초음파 세척함으로써 상당부분 제거 가능하다. 17O NMR 분광분석 결과, 짧은 펄스 길이(0.175μs)를 이용한 17O NMR 스펙트럼에서 Si-O-Si와 Si-OH 산소원자 환경이 거의 구분되지 않고 나타나는 반면, 특정 실험조건(2μs 펄스길이)의 17O NMR 스펙트럼에서는 약 0 ppm에서 빠른 동역학적 특성을 가지는 Si-OH로 추정되는 피크가 관찰되었다. 이 피크는 비정질 실리카겔 표면의 유기 리간드가 제거됨에 따라 더 뚜렷하게 관찰되며, 이는 유기 리간드와 비정질 실리카의 산소원자 사이의 상호작용이 존재함을 지시한다. 이와 같은 상호작용은 비정질 실리카겔 표면의 수산기의 원자구조에 대한 정보를 제공하며, 이를 통해 규산염 지구물질의 탈수반응 기작에 대한 이해를 고양시킬 수 있다. 따라서 궁극적으로 지구물질의 탈수반응에 기인하여 일어나는 섭입대의 중간깊이(약 70~300 km)에서 일어나는 지진의 미시적인 원인에 대한 실마리를 제시할 것으로 기대된다.

Novel N2O2 tetradentate ligands, H-3BPD and H-2BPD were synthesized. Hydrochloric acid salts of Br-3BPD, Cl-3BPD, Br-2BPD and Cl-2BPD having Br and Cl substituents at the para position of the phenol hydroxyl group, were synthesized. The ligands were characterized by C. H. N atomic analysis, 1H NMR, 13C NMR, UV-visible, and mass spectra. The proton dissociation constants (logKn H) of the phenol hydroxyl group and secondary amine of the synthesized N2O2 ligands were shown by four step wise values. The orders of the calculated overall proton dissociation constants (logβp) were Br-3BPD < Cl-3BPD < H-3BPD in case of 3BPD and Br-2BPD < Cl-2BPD < H-2BPD in case of 2BPD respectively. The order agreed well with that of para Hammett substituent constants(δp). The stability constants(logKML) of the complexes between the synthesized ligands and transition metal(II) ions agreed with the order of logβp of the ligands. The order of the logKML value of the each transition metal (II) ion was Co(Ⅱ) < Ni(Ⅱ) < Cu(Ⅱ) > Zn(Ⅱ) > Cd(Ⅱ) > Pb(Ⅱ), which agreed well with that of Iriving-Williams series.

new N3-O2 pentadentate ligand, H-BHPT, was synthesized. Hydrochloric acid salts of Br-BHPT, Cl-BHPT, CH3O-BHPT and CH3-BHPT, having Br-, Cl-, CH3- and CH3O- substituents at the para position of the phenol hydroxyl group of H-BHPT were synthesized. Hydrochloric acid salts of 3OH-BHPT and 4OH-BHPT, having different position of the phenol hydroxyl group of H-BHPT were also synthesized. The synthesis of each ligand was confirmed by C. H. N. atomic analysis and 1H NMR, 13C NMR, UV-visible, and mass spectra. The calculated proton dissociation constants (logKn H) of the phenol hydroxyl group and secondary amine group of the synthesized N3-O2 ligands showed five steps of the proton dissociations. The order of the overall proton dissociation constants (logβp) of the ligands was Br-BHPT < Cl-BHPT < H-BHPT < CH3O-BHPT < CH3-BHPT. The order agreed with that of Hammett substituent constants (δp). However, dissociation steps of 3OH-BHPT were four and that of 4OH-BHPT was three. The calculated stability constants (logKML) between the ligands and transition metal ions agreed with the order of logβp values of the ligands. The order of the stability constants between the transition metal ions with the synthesized ligands was Co(Ⅱ) < Ni(Ⅱ) < Cu(Ⅱ) > Zn(Ⅱ) > Cd(Ⅱ) > Pb(Ⅱ). The order agreed well with that of the Iriving-Williams.

A new N3O2 pentadentate ligand, N,N'-Bis(2-hydroxybenzyl)-ethylenetriamine(H-BHET․3HCl) was synthesized. The hydrochloric acid salts of Br-BHET․3HCl, Cl-BHET․3HCl, CH3O-BHET․3HCl and CH3-BHET․3HCl containing Br-, Cl-, H-, CH3O- and CH3- groups at the para-site of the phenol group of the H-BHEP were synthesized. The structures of the ligands were confirmed by C. H. N. atomic analysis and 1H NMR, 13C NMR, UV-visible and mass spectra. The calculated stepwise protonation constants(logKnH) of the synthesized N3O2 ligands showed six steps of the proton dissociation. The orders of the overall protonation constants(logβp) of the ligands were Br-BHET < Cl-BHET < H-BHET < CH3O-BHET < CH3-BHET. The orders agreed well with that of para Hammett substituent constants(δp). The calculated stability constants(logKML) between the ligands and heavy metal ions (Co(Ⅱ) , Ni(Ⅱ), Cu(Ⅱ), Zn(Ⅱ), Cd(Ⅱ) and Pb(Ⅱ)) agreed well with the order of the overall proton dissociation constants of the ligands but they showed a reverse order in para Hammestt substituent constants(δp). The order of the stability constants between the heavy metal ions with the synthesized ligands were Co(Ⅱ) < Ni(Ⅱ) < Cu(Ⅱ) > Zn(Ⅱ) > Cd(Ⅱ) > Pb(Ⅱ).

Hydrochloric acid salt of a new N2O3 pentadentate ligand, N,N'-Bis(2-Hydroxybenzyl)-1,3-diamino-2-propanol(H-BHDP․2HCl) was synthesized. Br-BHDP․2HCl, Cl-BHDP․2HCl, CH3-BHDP․2HCl and CH3O- BHDP․2HCl having Br, Cl, CH3 and CH3O substituents at 5-position of the phenol group of H-BHDP․2HCl were also synthesized. The potentiometry study in aqueous solution revealed that the proton dissociations of the synthesized ligands occurred in four steps and their order of the calculated overall proton dissociation constants(logβp) was Br-BHDP〈 Cl-BHDP〈 H-BHDP〈 CH3O-BHDP〈 CH3-BHDP. The order showed a similar trend to that of Hammett substituent constants(δp). The order of the stability constants(logKML) was Co(Ⅱ)〈 Ni(Ⅱ)〈 Cu(Ⅱ)〈 Zn(Ⅱ)〈 Cd(Ⅱ)〈 Pb(Ⅱ). The order in their stability constants (logKML) of each transition metal complex agreed with that of the overall proton dissociation constants (logβp).

Hydrochloride acid salts of new N2O2 tetradentate ligands containing amine and phenol N,N'-bis(2-hydroxybenzyl)-o-phenylenediamine(H-BHP), N,N'-bis(5-bromo-2-hydroxybenzyl)-o-phenylenediamine(Br-BHP), N,N'-bis (5-chloro-2-hydroxybenzyl)-o-phenylene-diamine(Cl-BHP), N,N'-bis(5-methyl-2-hydroxybenzyl)-o-phenylene-diamine (Me-BHP) and N,N'-bis(5-methoxy-2-hydroxybenzyl)-o-phenylenediamine(MeO-BHP) were synthesized. The ligands were characterized by elemental analysis, mass and NMR spectroscopy. The elemental analysis showed that the ligands were isolated as dihydrochloride salt. The potentiometry study revealed that the proton dissociation constants(logKnH) of ligands and stability constants (logKML) of transition and heavy metals complexes. The order of the stability constants of each metal ions for ligands was Br-BHP < Cl-BHP < H-BHP < MeO-BHP < Me-BHP.

Hydrobromic acid salts of new N, N, O tridentate ligands containing phenol, 2-[(2-Methylamino- ethylamino)-methyl]-phenol(H-MMP․2HBr), 5-Bromo-2-[(2-Methylamino-ethylamino)-methyl]-phenol (Br- MMP․2HBr), 5-Chloro-2-[(2-Methylamino-ethylamino)-methyl]-phenol(Cl-MMP․2HBr), 5-Methyl-2-[(2-Methylamino- ethylamino)-methyl]-phenol(Me-MMP․2HBr), 5-Methoxy-2-[(2-Methylamino-ethylamino)- methyl]-phenol(MeO- MMP․2HBr) and 1-[(2-Methylamino-ethylamino)- methyl]-naphthalen-2-ol(Nap- MMP․2HBr) were synthesized. The synthesized ligands were confirmed by C. H. N. atomic analysis, UV-visible and IR spectroscopies, 1H NMR, 13C NMR and mass analysis. The potentiometry study revealed that the proton dissociation constants(logKnH) of the synthesized ligands and stability constants (logKML, logKML2) of transition metal complexes of Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Pb(II) ions occurred in three steps and the order of the calculated overall proton dissociation constants(logβp) and stability constants (logKML) of ligands was Br-MMP․2HBr < Cl-MMP․2HBr < H-MMP․2HBr < Nap-MMP․2HBr < Me-MMP․2HBr < MeO-MMP․2HBr. The order showed a similar trend to that of Hammett substituent constants(δp). The synthesized ligands usually form 2:1(ML2) complexes with transition metal ions. The order of the stability constants of each transition metal ions was Co(II) < Ni(II) < Cu(II) > Zn(II) > Cd(II) > Pb(II).

N,N-bis(2-salicylaldehyde)dipropylenetriamine(5-Hsaldipn), N,N-bis(5-bromosalicyl-aldehyde) dipropylenetriamine (5-Brsaldipn), N,N-bis(5-chlorosalicylaldehyde)dipropylene-triamine(5-Clsaldipn), N,N-bis(2-hydroxy-5-methoxybenzaldehyde)dipropylenetriamine(5-OCH3saldipn) and N,N-bis (2-hydroxy-5-nitrobenzaldehyde)dipropylenetriamine (5-NO2saldipn) were synthesized and characterized by elemental analysis, infrared spectrometry, NMR spectrometry and mass spectrometry. Their proton dissociation constants were determined in 70% dioxane/30% water solution by potentiometric. Stability constants of the complexes between these ligands and the metal ions such as Cu(Ⅱ), Ni(Ⅱ) and Zn(Ⅱ) were measured in dimethyl sulfoxide by a polarographic method. Stability constants for the ligands were in the order of 5-OCH3 ＞ 5-H ＞ 5-Br ＞ 5-Cl ＞ 5-NO2saldipn. Enthalpy and entropy changes were obtained in negative values.

The thiophene or furan-containing hexadentate ligands 1,12-bis (2-theophene)-2,5,8,11-tetraazadodecane(Thiotrien ․4HCl) and 1,12-bis (2-furan)-2,5,8,11-tetraazadodecane(Furatrien․4HCl) were synthesized as their tetrahydrochloride salt and characterized by EA, IR, NMR, and Mass spectrum. Their protonation constants (logKnH) and stability constants (logKML) for Cd2+, Pb2+, Zn2+ and Cu2+ ions were determined in aqueous solution by potentiometry and compared with 1,12-bis(2-pyridyl)-2,5,8,11-tetra-azadodecane(Pytrien) of pyridyl-containing ligand. The effect stability constants of ligands and metal ion for removal of heavy metals in aqueous solution were described.