• 한국환경과학회지
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• 제23권6호
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• pp.1151-1156
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• 2014

The photocatalytic decomposition characteristics of single n-pentane, n-pentane mixed with methyl ethyl ketone (MEK), and n-pentane mixed with ethyl acetate (EA) by cylindrical UV reactor installed with $TiO_2$-coated perforated plane were studied. The effects of the residence time, the inlet gas concentration, and the oxygen concentration were investigated. The removal efficiency of n-pentane was increased with increasing the residence time and the oxygen concentration, but decreased with increasing the inlet concentration of n-pentane. The photocatalytic decomposition rates of single n-pentane, n-pentane mixed with MEK, and n-pentane mixed with EA fitted well on Langmuir-Hinshelwood kinetics equation. The maximum elimination capacities of single n-pentane, n-pentane mixed with MEK, and n-pentane mixed with EA were obtained to be $465g/m^3{\cdot}day$, $217g/m^3{\cdot}day$, and $320g/m^3{\cdot}day$, respectively. The presence of coexisting MEK and EA vapor had a negative effect on the photocatalytic decomposition of n-pentane and the negative effect of MEK was higher than that of EA.

• 멤브레인
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• 제22권4호
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• pp.251-257
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• 2012

n-Pentane의 분리 및 회수를 위해 분리막의 제조가 용이하고 유기용매에 대한 내용매성이 있는 polyetherimide (PEI)를 지지체로 poly (dimethyl siloxane) (PDMS)를 코팅하여 중공사 복합막을 제조하였다. 제조된 기체 분리막의 특성을 알아보기 위하여 n-Pentane과 질소를 이용하여 공급농도와 stage cut의 변화에 따른 n-pentane과 질소의 투과도, permeate, retentate의 농도, 농축도, 회수율을 측정하였다. n-pentane과 질소의 투과도는 각각 2485.3, 9.9 GPU를 나타내었고, stage cut이 감소하고 공급농도가 증가할수록 투과측의 n-pentane 농도는 증가하는 경향을 나타내었다. 반면 회수효율의 경우에는 stage cut이 증가할수록 공급농도가 감소할수록 증가하는 경향을 나타내었다.

• Bulletin of the Korean Chemical Society
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• 제20권8호
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• pp.897-904
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• 1999

We have presented the thermodynamic, structural and dynamic properties of liquid pentane isomers - normal pentane, isopentane, and neopentane - using an expanded collapsed atomic model. The thermodynamic properties show that the intermolecular interactions become weaker as the molecular shape becomes more nearly spherical and the surface area decreases with branching. The structural properties are well predicted from the site-site radial, the average end-to-end distance, and the root-mean-squared radius of gyration distribution func-tions. The dynamic properties are obtained from the time correlation functions - the mean square displacement (MSD), the velocity auto-correlation (VAC), the cosine (CAC), the stress (SAC), the pressure (PAC), and the heat flux auto-correlation (HFAC) functions - of liquid pentane isomers. Two self-diffusion coefficients of liquid pentane isomers calculated from the MSD's via the Einstein equation and the VAC's via the Green-Kubo relation show the same trend but do not coincide with the branching effect on self-diffusion. The rotational re-laxation time of liquid pentane isomers obtained from the CAC's decreases monotonously as branching increases. Two kinds of viscosities of liquid pentane isomers calculated from the SAC and PAC functions via the Green-Kubo relation have the same trend compared with the experimental results. The thermal conductivity calculated from the HFAC increases as branching increases.

• 청정기술
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• 제10권3호
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• pp.169-176
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• 2004

촉진 수송 분리 막은 $Ag^+$ 이온과 올레핀 사이에서 ${\pi}$-complexation을 형성하고, 촉진 수송 현상에 의하여 올레핀을 선택적으로 분리한다. 본 연구에서는 Isoprene/n-pentane 분리를 위해 Sulfonated poly(ether ether)ketone (SPEEK)-$AgNO_3$로 이루어진 촉진 수송 분리 막을 제조하여 실험하였다. 이 분리 막은 isoprene의 좋은 선택도와 투과도를 나타내었고 장시간 동안 안정하게 분리 막의 성능을 유지하였다. SPEEK는 다양한 합성 조건에 따라서 degree of sulfonation (DS)가 많은 차이를 나타냈고, 1H NMR spectroscopy를 사용하여 제조된 SPEEK의 DS를 측정하였다. 이렇게 제조된 SPEEK를 이용한 분리 막의 선택도나 투과도와 같은 성능은 SPEEK의 DS에 의해 영향을 받았다. SPEEK의 DS가 높을수록, n-pentane에 대한 isoprene의 선택도는 최대 850 ~ 900까지 증가하였고, 또한 막의 안정성 역시 100시간 이상 유지되었다.

• 대한화학회지
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• 제49권1호
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• pp.16-28
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• 2005

• Macromolecular Research
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• 제11권4호
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• pp.231-235
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• 2003

Phase behavior information is necessary for accomplishing homogeneous copolymerization to obtain high yield of copolymers and prevent a fouling problem. Cloud-point data to $160^{\circ}C$ and 1,450 bar are presented for five $C_6$ hydrocarbon solvents, normal hexane, 2,2-dimethyl butane, 2,3-dimethyl butane, 2-methyl pentane, and 3-methyl pentane, with poly(ethylene-co-53 mol% norbornene) ($PEN_{53}$). The pressure-concentration isotherms measured for $PEN_{53}$/n-hexane have maximums that range between 5 and 12 wt% $PEN_{53}$. The cloud-point curves for $PEN_{53}$ all have negative slopes that decrease in pressure with temperatures. The single-phase region of $PEN_{53}$ in n-hexane is larger than the regions in 2,2-dimethyl butane, 2,3-dimethyl butane, 2-methyl pentane, and 3-methyl pentane. The cloud-point curve of $PEN_{53}$ in 2,2-dimethyl butane is located at higher temperatures and pressures than the curve in 2,3-dimethyl butane due to the reduced dispersion interactions with and limited access of 2,2-dimethyl butane to the copolymer. Similar cloud-point behavior is observed for $PEN_{53}$ in 2-methyl pentane and 3-methyl pentane.

• 한국약용작물학회지
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• 제4권1호
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• pp.31-37
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• 1996

광릉쥐오줌풀 뿌리의 정유성분 조성 및 정유의 특성을 더욱 정밀하게 조사하기 위하여 수증기 증류에 의해 얻어진 정유성분을 산성, 페놀성, 염기성 및 중성성분 분획으로 분리하여 분획별 향의 관능평가 및 분획물의 조성을 조사한 결과는 다음과 같다. 1. 광릉쥐오줌풀 뿌리의 정유성분분획물 각각의 조성은 중성성분 분획물 92%, 산성성분 분획물 6%, 염기성성분 및 페놀분획물은 각각 1% 미만이며 각 분획물의 향특성은 중성성분 분획은 sweet-balsamic, woody, musky, medicinal 향이며 산성성분 분획은 sweat-socks, valeric-like, cheese-like 향이었다. 2. 중성성분분획물을 용매의 극성을 달리하여 분획한 결과 용출 용매별 분획 비율은 ethyl ether분획물이 44%, pentane : ethyl ether분획물 34%, pentane과 methanol분획물은 각각 11%였다. 분획별 향 특성은 ethyl ether 분획물은 woody, medicinal 향이며 pentane :. ethyl ether 분획물은 sweet-balsamic, woody, herb-like향 특성을 나타내었다. 극성을 달리한 용출용매별 분획물에서 확인된 성분은 ethyl ether 분획물에서 valeranone 등 12종, pentane : ethyl ether(9 : 1) 분획물에서는 bornyl acetate등 26종, pentane 분획물에서 camphene등 43종을 확인하였다. 3. 산성성분분획에서는 n-butanoic acid 외 44종을 확인하였고 그 중 양적으로 많은 성분은 3-methyl butanoic acid 42.1%, dimethoxy-2-propanoic acid 11.5%, 5-ethyldihydro-2H-furanone 5.7% 등 이었다.

• 월간산업보건
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• 통권268호
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• pp.25-27
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• 2010

Pentane과 그것의 이성질체에 대한 TLV-TWA는 600 ppm($1770\;mg/m^3$)으로 권고하고 있다. 이 수치는 염증이나 혼수 마비 상태를 최소화하기 위해 설정되었다. 권고된 TLV는 마비 효과를 억제하기 위한 충분한 안전 범위를 제공해 준다. 그러나 매우 높은 농도에 만성적으로 노출되면 다발 신경성 홍반 수종증을 유발할 수 있다는 가능성은 헥산의 신경독성과 비교했을 때 pentane이 낮은 독성이라 하여도 무시할 수는 없다. 피부(skin), 감작제(SEN), 발암성, TLV-STEL에 대한 수치는 충분한 데이터가 확보되지 않아 현재는 권고하지 않고 있다.

• Bulletin of the Korean Chemical Society
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• 제3권2호
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• pp.76-78
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• 1982

Ethanolic tetracarbonylhydridoferrate solution combined with glutaraldehyde is a very effective reducing agent for the selective transformation of two moles of secondary amines into pentane-1,5-diamine derivatives. A variety of aliphatic secondary amines react with ferrate-glutaraldehyde at room temperature under carbon monoxide to give the corresponding N-substituted pentane-1,5-diamines in reasonable yields.

• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.1978-1980
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• 2009

A mesostructured form of carbon was fabricated from a template of mesostructured silica by using pentane, an aliphatic hydrocarbon precursor. To synthesize the mesostructured silica, a buffered (pH of 6.5) mixture of nonionic Pluronic P123 surfactant, sodium silicate, and acetic acid were used. The impregnated silica with Fe$(CO)_5$ (wt 5%) and pentane was placed in a quartz tube, treated with pentane vapor at 800 ${^{\circ}C}$ for two hours to synthesize the mesostructured carbon. The XRD patterns of the carbon replica in the low/wide angle regions, its TEM images, and nitrogen adsorption-desorption isotherm revealed that the long-range framework order of mesostructure with the pore size centered on 2.8 nm was maintained to some extent mainly due to some portions of mesophase carbon that work as a support to fix the hexagonal frameworks by anchoring on the pore surface with an improved graphitic character. The dc conductivity of the mesostructured carbon in pressed powder form at 6.0 MPa was 2.08 S/cm.