• Bulletin of the Korean Chemical Society
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• 제17권12호
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• pp.1109-1111
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• 1996

The Podand Ⅰ (Figure 1) has been studied as cation carrier in a bulk liquid membrane system. Ag+ and some other transition metal ions (M2+=Cu, Ni, Co, Zn, and Cd) have been transported using the podand as carrier in a bulk liquid membrane system. Studies on the transport of equimolar mixtures of two or three competing components have also been carried out with the same system. Ag+ exhibited a higher transport rate than the other M2+ in the competitive experiments. Ligand structure and the equilibrium constant for complex formation are important parameters in the transport of the metal ions.

• Fibers and Polymers
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• 제3권1호
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• pp.14-17
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• 2002

Development of a novel fixed site carrier membrane (FCM), supported by PET fabric for metal ion separation is reported. The membranes were prepared by dipping PET fabric into the methylene chloride solution of Poly(5-vinyl-m-phe-nylene-m'-phenylene-32-crown-10) (P(VCE)), a polymeric metal ion carrier. It was found that the flux of mono-valent metal ion transported across the membrane is signif=cantly differed from each other and the flux decreases in the order $Cs^+$>$Rb^+$>$K^+$>$Na^+$>$Li^+$ irrespective to the anion except perchlorate anion. It was explained in terms of the stability of the complex, formed by crown ether unit of the P(VCE) and the various metal ions, meanwhile, the lower rate of transport in the presence of perchlorate anion was ascribed to its low hydrophilicity.

• 한국재료학회지
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• 제9권5호
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• pp.473-477
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• 1999

Xerographic properties of double-layer photoconductor doped with 4-butyl-4'-methoxyazobenzene (BMAB) as charge-carrier transport material were investigated. BMAB can undergo reversible trans-cis isomerization by light with appropriate wavelength. In the results of measured surface voltage properties for photoconductor doped with BMAB, TNF: BMAB(4-wt%) sample with trans form showed the lowest dark decay, the lowest residual voltage, and the highest sensitivity among cis form. The trans isomer of BMAB has ordering orientation because the molecule possesses a rodlike shape, while the cis isomer has random orientation due to its bent shape. Therefore the molecular arrangement of trans form enhanced charge-carrier transport mobility.

• Membrane and Water Treatment
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• 제9권1호
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• pp.23-31
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• 2018

In this study, a new method called as multi-dropped liquid membrane (MDLM) which is more practical and more effective than other liquid membrane techniques is applied for transport of Zn(II) has been studied. HCl as the stripping solution and D2EHPA dissolved in kerosene as the membrane solution, has been examined. The effects of stripping solution concentration, carrier concentration, temperature and pH in the feed phase on the transport of Zn(II) have also been investigated. As a result, the optimum transport conditions of Zn(II) were obtained, i.e., the concentration of HCl solution was 0.25 M, the concentration of D2EHPA was $8{\times}10^{-3}M$, and pH value in the donor phase was 5.00. Under the optimum conditions, the transport percentage of Zn(II) was up to >99% during the transport time of 80 min when the initial concentration of Zn(II) was $120mgL^{-1}$. The activation energy is calculated as $5.30kcalmol^{-1}$. The value of calculated activation energy indicates that the process is diffusionally controlled by Zn(II) ions. The experiments have demonstrated that D2EHPA derivative is a good carrier for Zn(II) transport through MDLM in the study.

• Coupled systems mechanics
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• 제6권1호
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• pp.75-96
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• 2017

As electron donor/acceptor materials for organic photovoltaic cells, small-molecules donors/acceptor are attracting more and more attention. In this work, we investigated the electronic structures, electrochemical properties, and charge carrier transport properties of four recently-synthesized small-molecule donors/acceptor, namely, DPDCPB (A), DPDCTB (B), DTDCPB (A1), and DTDCTB (B1), by a series of ab initio calculations. The calculations look into the electronic structure of singly oxidized and reduced molecules, the first anodic and cathodic potentials, and the electrochemical gaps. Results of our calculations were in accord with those from experiments. Using Marcus theory, we also computed the reorganization energies of hole/electron hoppings, as well as hole/electron transfer integrals of multiple possible molecular dimer configurations. Our calculations indicated that the electron/hole transport properties are very sensitive to the relative separations/orientations between neighboring molecules. Due to high reorganization energies for electron hopping, the hole mobilities in the molecular crystals are at least an order of magnitude higher than the electron mobilities.

• 항공우주정책ㆍ법학회지
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• 제27권2호
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• pp.107-142
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• 2012

현대 사회에서 항공기는 중요한 운송수단으로 자리매김 하였고 항공 여객운송에 있어서 항공기 연착 손해로 인한 분쟁은 항공운송 관련 분쟁 중 가장 많이 발생하는 일이다. 항공운송에 관한 국제조약이 적용되지 못하는 국내운송 등과 같은 영역을 규율하기 위하여 2011년 상법 항공운송편이 제정 발효되었고 여기에 여객 및 수하물의 연착으로 인한 항공운송인의 손해배상책임제도도 마련되었다. 몇 개 안되는 조문이지만 항공운송 중 가장 빈번히 일어나는 항공기 연착으로 인한 손해배상 문제를 규율하기 때문에 그 중요성은 매우 크다고 할 수 있다. 기존의 바르샤바협약 체제의 문제점을 개선한 1999년 몬트리올협약의 관련 내용을 대부분 수용하여 제정된 우리 상법 항공운송편 규정들은 널리 통용되고 있는 국제적 기준에 부합한다는 장점은 있지만, 1999년 몬트리올협약의 문제점들을 거의 그대로 지니고 있다는 단점이 있다. 상법 항공운송편상 여객 및 수하물의 연착 손해로 인한 배상책임제도 관련 규정들의 문제점 및 개선방안은 다음과 같다. 첫째, 연착으로 인한 항공운송인의 손해배상책임이 성립되기 위한 '연착'의 개념 정의가 없으므로 '연착'에 관한 정의 규정을 두는 것을 생각해 볼 필요가 있다. 둘째, 여객에 대한 연착 손해 발생 시 국내운송의 경우 국제운송의 1/8 수준으로 항공운송인의 배상책임한도액을 차등하여 규정한 것은 항공사보호에 별로 도움이 되지 않는 반면 소비자 피해의 구제 측면에서는 바람직하지 않으므로 국내운송의 여객 연착 손해 관련 배상책임한도액을 국제운송의 1/4~1/2 수준으로 상향 조정하는 것이 바람직하다고 본다. 셋째, 수하물의 멸실 훼손의 경우와 연착의 경우를 구분 없이 수하물의 손해로 인한 항공운송인의 배상책임한도액을 모두 동일하게 규정하고 있는 것은 일반적으로 손해의 정도가 다른 대상들을 구분하지 않았기 때문에 문제가 있다고 생각되며, 수하물의 멸실 훼손의 경우와 연착의 경우를 구분하여 별도로 배상책임한도액을 규정하는 것이 바람직하다고 생각된다. 위에서 언급된 상법 항공운송편의 여객 및 수하물의 연착 손해 관련 배상책임 규정의 문제점 등을 비롯한 동 법률의 개선요구들에 대한 많은 연구와 논의를 통해 오랜 노력과 기다림 끝에 제정된 국내 항공운송법제를 더욱 발전시켜 나가야 할 것이다.

• 한국막학회:학술대회논문집
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• 한국막학회 2002년도 춘계 총회 및 학술발표회
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• pp.106-109
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• 2002

No Abstract, See Full-text

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2001년도 가을 학술발표회 논문집
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• pp.219-222
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• 2001

Membranes which selectively transport specific metals on an industrial scale is much useful in a number of applications, such as aqueous stream purification, catalyst and recycling of the reactants, the applications in metal ion sensing and so forth. Numerous studies have been already made to use liquid, supported liquid and, emulsion liquid membranes (LM) for selective carriers for metal ion transport. (omitted)

• Macromolecular Research
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• 제12권2호
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• pp.145-155
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• 2004

Facilitated transport membranes for the separation of olefin/paraffin mixtures have long been of interest in separation membrane science because olefins, such as propylene and ethylene, which are important chemicals in petrochemical industries, are currently separated by energy-intensive cryogenic distillation processes. Recently, solid polymer electrolyte membranes containing silver ions have demonstrated remarkable performance in the separation of olefin/paraffin mixtures in the solid state and, thus, they can be considered as alternatives to cryogenic distillation. Here, we review recent progress, and critical issues affecting in the use of facilitated olefin transport membranes; in particular, we provide a general overview with reference to carrier properties, transport mechanisms, and separation performance.

• 대한전자공학회논문지
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• 제15권2호
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• pp.19-21
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• 1978

Cholesteryl Benzoate 액정에서 전류 수송기구를 규명하기 위하여 charge carrier의 어i도 mobilits를 극성 반전법을 사용하여 140∼185℃의 온도 영 역에서 측정했다. charge carrier의 drift mobilits는 주위온도가 증가함에 따라 2.5×10-7㎠/V.sec에서 2.0×10-6㎠/V.sec까지 증가했다. 이 실험결과로 부터 전류 수송기구는 ionic기구로 설명할 수 있다.