• 한국대기환경학회지
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• 제34권4호
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• pp.554-566
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• 2018

The rice husk contains nutrients which can be easily utilized by microorganisms, and also has a water retaining ability, which played a crucial part in enabling it to become a biofilter media. In this study, we evaluated the applicability of rice husk pellet bio-scrubber as a microbiological carrier. The pelletization experiment of rice husk as a biological media was performed using PVA and EVA binder. Also, the feasibility tests of rice husk as a biological media for odor removal were carried out in order to know whether rice-husk contains useful components as a media for microbiological growth or not. Lastly, a combined test for odor gas absorption and biological oxidation was conducted using a lab scale bio-filter set-up packed with rice-husk pellets as wet-scrubber. The major components of the rice husk were carbon, hydrogen, nitrogen, and oxygen, while carbon acted as the main ingredient which comprised up to 23.00%. The C : N : P ratio was calculated as 45 : 1 : 2. Oxygen uptake rate, yield and decay rate of the rice husk eluent was calculated to be $0.0049mgO_2/L/sec$, 0.24 mgSS/mgCOD and 0.004 respectively. The most stable form of rice husk pellets was produced when the weight of the rice husk, EVAc, PVAc, and distilled water was 10 : 2 : 0.2 : 10. The prepared rice husk pellets had an apparent density of 368 g/L and a porosity of 59.00% upon filling. Dry rice husks showed high adsorption capacity for ammonia gas but low adsorption capacity for hydrogen sulfide. The bio-filter odor removal column filled with rice husk pellets showed more than 99.50% removal efficiency for NH3 and H2S gas. Through the analysis of circulation water, the prime removal mechanism is assumed to be the dissolution by water, microbial nitrification, and sulfation. Finally, it was confirmed that the microorganisms could survive well on the rice husk pellets, which provided them a stable supply of nutrients for their activity in this long-term experiment. This adequate supply of nutrients from the rice husk enabled high removal efficiency by the microorganisms.

• Journal of Photoscience
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• 제9권2호
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• pp.317-319
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• 2002

All-optical switching has been demonstrated in bacteriorhodopsin (bR) based on nonlinear intensity induced excited state absorption. The transmission of a cw probe laser beam at 410 nm corresponding to the peak absorption of M state through a bR film is switched by a pulsed pump laser beam at 570 nm that corresponds to the maximum initial 8 state absorption. The switching characteristics have been analyzed using the rate equation approach considering all the six intermediate states (B, K, L, M, N and 0) in the bR photocycle. The switching characteristics are shown to be sensitive to life time of the M state, absorption cross-section of the 8 state at probe wavelength ($\sigma$ $\_$Bp/) and peak pump intensity. It has been shown that the probe laser beam can be completely switched off (100 % modulation) by the pump laser beam at relatively low pump powers, for $\sigma$$\_$Bp/ = O. The switching characteristics have been used to design all-optical NOT, OR, AND and the universal NOR and NAND logic gates for optical computing with two pulsed pump laser beams.

• Journal of Pharmaceutical Investigation
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• 제36권2호
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• pp.137-142
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• 2006

A bioequivalence of Daewoong $Alendronate^{TM}$ (Daewoong Pharmaceutical Co., Ltd., Korea) and $Fosamax^{TM}$ tablets (MSD Korea) was evaluated according to the guideline of Korea Food and Drug Administration (KFDA). A single 70 mg dose of sodium alendronate of each medicine was administered orally to 56 healthy male volunteers. This study was performed in a $2\;{\time}\;2$ crossover design. Concentrations of alendronate in the urine were monitored by a high-performance liquid chromatography (HPLC). $A_{et}$ (cumulative urinary excreted amount from time 0 to last sampling interval) was calculated by the accumulation of the urinary excreted alendronate. $U_{max}$ (maximum urinary excretion rate) and $T_{max}$ (time to reach $U_{max}$) were compiled from the urinary excretion rate - time data. Analysis of variance was performed using logarithmically transformed $A_{et}$ and $U_{max}$. No significant sequence effect was found for all of the bioavailability parameters. The 90% confidence intervals of the $A_{et}$ and $U_{max}$ for Daewoong $Alendronate^{TM}/Fosamax^{TM}$ were 0.89-1.12 and 0.82-1.02, respectively. This study demonstrated the bioequivalence of Daewoong $Alendronate^{TM}$ and $Fosamax^{TM}$ with respect to the rate and extent of absorption.

• 농업생명과학연구
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• 제52권6호
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• pp.81-88
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• 2018

본 연구는 축산분뇨를 퇴비화 하는 과정에서 흔히 사용되는 수분조절제인 톱밥, 왕겨 등을 대체하여 사용할 수 있고 또한 재사용 여부를 판단하기 위하여 수분조절제 6종을 대상으로 특성을 분석하였다. 그 결과 본 실험에 사용한 수분조절제의 종류에 관계없이 유해성분의 함량은 0.0~34.1ppm으로써 농촌진흥청에서 제시하고 있는 유해성분의 최대함량인 5.0~900.0ppm보다 상당히 적은 것으로 나타나 톱밥이나 왕겨 등을 대체가 가능할 것으로 판단되었다. 그리고 수분조절제 원상태의 함수율은 최소 12.4%에서 최대 16.6%까지 측정되어 적정 함수율인 60%이하 보다는 낮아 수분조절제로서의 기능이 충분한 것으로 나타났다. 흡수율은 최소 31.9%에서 최대 600.0%까지 나타나 수분조절제의 종류에 따라 큰 차이를 보였지만, 가장 적절한 수분조절제는 우드펠릿인 것으로 나타났다. 우드브리켓만 보면, A사 제품이 가장 높게 나타났고 그 다음으로 C사 및 B사 제품 순으로 나타났다. 전단강도는 전단강도를 측정할 수 없었던 재료를 제외한 5가지 종류에서 원상태의 경우, 평균 271.7N정도로서 가장 크게 나타났다. 그 다음으로 건조 및 흡수상태로서 평균 전단강도가 각각 78.0N 및 27.7N정도로 나타났다. 우드브리켓의 경우, A사 제품이 B, C사 제품보다 상대적으로 전단강도가 현저히 작게 나타났다. 전체적으로 볼 때, 전단강도는 흡수율이 작으면 상대적으로 크게 나타나는 경향이 있었다. 특히 소나무 우드칩이나 참나무 절단목의 경우, 흡수상태에서도 전단강도가 다른 재료에 비해 상대적으로 크기 때문에 돈분과의 교반시 어느 정도의 동력을 견딜 수 있을 것으로 나타났다.

• Molecules and Cells
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• 제28권6호
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• pp.515-520
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• 2009

Applications of bone marrow-derived mesenchymal stem cells in gene therapy have been hampered by the low efficiency of gene transfer to these cells. In current transduction protocols, retrovirus particles with foreign genes make only limited contact with their target cells by passive diffusion and have short life spans, thereby limiting the chances of viral infection. We theorized that mechanically agitating the virus-containing cell suspensions would increase the movement of viruses and target cells, resulting in increase of contact between them. Application of our mechanical agitation for transduction process has increased the absorption of retrovirus particles more than five times compared to the previous static method without changing cell growth rate and viability. The addition of a mechanical agitation step increased transduction efficiency to 42%, higher than that of any other previously-known static transduction protocol.

• 생물환경조절학회지
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• 제6권4호
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• pp.292-298
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• 1997

본 연구에서는 반사필름 멀칭과 북측면의 반사판설치에 의한 보광이 토마토의 광이용에 미치는 영향을 밝히기 위해 토양 및 수경재배를 통해 토마토의 엽온변화, 기공특성, 증산.광합성속도 등의 변화들을 중심으로 검토하였다. 보광 처리에 의해 토마토엽의 기공밀도는 증가하였으나 기공의 크기와 면적은 차이가 얼었다. 근권부의 삼투포텐셜이 낮으면 광반사에 의한 기공저항이 컸고 증산속도는 낮았으며 엽온은 40.62$^{\circ}C$까지 상승했다. 또한 보광에 의해 광합성속도도 저하했으나 엽록소 함량에는 차이가 없었다. 반사필름 멀칭으로 온실가루이의 기피효과는 있었다 약광기 동절기에 반사필름 멀칭 등의 보광처리에 의한 증수나 품질향상은 엽의 기공밀도의 증가로 활발한 증산 .광합성작용으로 체내의 물질대사나 생장에 영향을 주고 그 결과 간접적으로 무기성분의 흡수나 분배에 영향을 주어 생육 및 수량 둥이 양호했다고 생각된다.

• 생물환경조절학회지
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• 제10권4호
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• pp.207-212
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• 2001

인간거주 모듈과 식물생산 모듈로 구성된 밀폐형 식물생산시스템에서 시스템의 환경특성, 상추의 NO$_2$ 흡수율 및 생육반응이 조사되었다. 잎이 4-5개인 상추는 10cm 직경의 포트에 정식된 후, NO$_2$ 농도가 제어되는 식물모듈에서 재배되었다. NO$_2$가 포함된 인간 모듈의 공기는 다이어프램에 의하여 10분 ON, 20분 OFF 형태로 인간모듈과 식물모듈 사이로 순환되었다. NO$_2$농도가 0.13, 0.30 및 0.45 $\mu$mol.mol$^{-1}$로 일정하게 유지되는 조건에서 10분 동안 NO$_2$는 각각 0.040, 0.109, and 0.149$\mu$mol.mol$^{-1}$ 감소되었다. 상추의 NO$_2$흡수율은 처리조건중 0.45$\mu$mol.mol$^{-1}$에서 0.078$\mu$mol.mol$^{-1}$.m$^{-2}$ .$min^{-1}$로 추정되었으며, 이 경우에도 상추의 가시적인 장해는 나타나지 않았다. 정식후 4-5일째에 NO$_2$0.45 $\mu$mol.mol$^{-1}$에 노출된 상추의 광합성 속도는 노출되지 않은 대조구에 비하여 엽폭, 엽장, 생체중, 건물중에 품질 등에서 큰 차이가 없었다.

• 환경위생공학
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• 제13권2호
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• pp.88-94
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• 1998

This study was investigated the application of biofiltration using cometabolic process to remediate gaseous toluene that are highly recalcitrant to adsorption, absorption and biodegradation. The investigation was conducted using specially built steel columns packed with granular activated carbon for removal of toluene and G.A.C was also coated with Pseudomonas putida microorganisms by addition of KH$_{2}$PO$_{4}$. The biofilter unit was operated in the condition of dry and 27.5% moisture content at gas loading rate of 12.5 l/min. Gaseous toluene taken from tedlar bag was analyzed by the use of G.C. equipped with F.I.D. detector. The removal efficiency of gaseous toluene was 85% at average inlet concentration of 970 ppm during dry operating condition. For gaseous toluene, 91% removal efficient was obtained at the filter material with moisture content and 97% removal efficiency was obtained with Pseudomonas putida microorganisms at gas loading rate of 12.5 l/min.

• 농업과학연구
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• 제46권4호
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• pp.931-939
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• 2019

Biochar is a solid carbon material made by pyrolyzing a biomass under limited oxygen conditions. Biochar has been reported to confer various benefits, such as increased soil productivity, pollutant absorption, and reduced greenhouse gas. In this study, oak pyrolyzed at 600℃ for 3 hours was either powdered or pelleted. Each of the biochar types was added to the soil at a rate of 2%. The control did not receive any biochar while a combination of the biochar and NPK treatment (biochar 2% + NPK) was also included. The cherry tomatoes were grown in greenhouse pots for 50 days to compare the growth characteristics of the different treatments. The cherry tomato with the powdered biochar 2% + NPK treatment had the heaviest plant fresh shoot weight of 276.4 g and the highest chlorophyll content of 59.3 SPAD. The control had the lightest plant fresh shoot weight of 44.2 g and a chlorophyll content of 26.5 SPAD. Both forms of biochar affected the chemical properties of the soil, increased the pH, electrical conductivity, available phosphate, total carbon and total nitrogen and positively influenced the cherry tomato growth and productivity. From the above results, therefore, both biochar forms are suited for use as soil amendments.

• 공업화학
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• 제16권6호
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• pp.790-793
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• 2005

최근 인간의 생명 연장과 건강 등에 관심이 많아지면서 약학 및 의학계는 생체 내에서 보다 안정적이며 효과를 나타낼 수 있는 약물 전달 시스템의 개발에 많은 힘을 기울이고 있는 실정이다. 수많은 생화학 연구자들은 키토산이 인체에 거부반응이 없으며 약물과 백신의 전달을 효율적이고 안전하게 흡착능력을 향상시킨다는 것을 밝혀 왔다. 또한 그것은 생분해성, 생체 친화적이라는 장점 때문에 약물 방출 조절에 적당하다고 알려져 있다. 본 연구에서는 생명고분자인 키토산의 나노입자를 제조하여 농도, pH, 최적 온도에서 약물 전달 조절을 in vivo 조건에서 수행하였다. 인슐린을 담지한 키토산 나노입자는 당뇨성 쥐의 혈당을 효과적으로 낮춰 줄 수 있음을 알 수 있었다.