• Title/Summary/Keyword: 선택과 제거

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A Study on the Permeation Properties of Permanent Gases and condensable Vapors through Hexamethyldisiloxane Plasma-Polymerized Membranes (Hexamethyldisiloxane 플라즈마 중합막을 통한 영구기체 및 응축성 증기의 투과특성에 관한 연구)

  • Oh, Sae-Joong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.3
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    • pp.699-706
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    • 2018
  • The permeation properties of plasma polymer membranes were studied for permanent gases such as He, $H_2$, $O_2$, $N_2$, $CH_4$ and condensable vapors such as $CO_2$, $C_2H_4$, $C_3H_8$. The plasma polymers were prepared by the discharge of microwave or radiofrequency(RF) wave. Hexamethyldisiloxane (HMDS) vapor was used as a monomer for plasma polymerization. In HMDS plasma-polymerized membranes prepared under microwave discharge, the permeability coefficient was dependent of the kinetic molecular diameter of the permeate gases. Additionally the membranes showed higher $O_2/N_2$ permselectivity compared to the plasma polymers from radiofrequency discharge. On the contrary, in the HMDS plasma-polymerized membranes prepared under radiofrequency discharge, the permeability coefficient was dependent of the critical temperature of the permeant gases. The membranes showed high selectivities of $C_2H_4$ and $C_3H_8$ over $N_2$. The permeability coefficient of plasma polymerized membranes prepared under microwave discharge was dependent of the molecular diameter of permeant gases because of high crosslinking density of the membrane. However, the crosslinking density of the plasma polymerized membranes prepared under RF discharge was lower because the energy density of RF wave is weaker than that of microwave. Hence, the permeability of RF plasma polymerized membranes became dependent of the critical temperature rather than molecular diameter of the gases.

Study of the enzymatic action of the chymopapain using pluronic based nano-carrier system on the cadaveric nucleus pulposus tissue (플루로닉(pluronic) 기반의 나노운반체(nano-carrier)에 충진된 카이모파파인(chymopapain)의 척추 추간판 조직내 작용성에 관한 연구)

  • Choi, Won Il;Tae, Gi Yoong;Hong, Young Ki
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.1
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    • pp.585-592
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    • 2015
  • The objective of this study is to determine if when chymopapain is loaded onto a nano-carrier, an injection of it reduces the spreading range of the drug within the discs. The materials for the experiment, which were conducted for three weeks, included fifteen intervertebral discs taken from two cadavers, which were divided according to the types of injected chymopapain solutions as follows: ordinary chymopapain group and nano-carrier system group. The nano-carrier system group was again divided into two subgroups according to the types of pluronics, the basic material for the nano-carriers: Pluronic F 127(DA-PF 127) in the nano-carrier group and Pluronic F 68(DA-PF 68) in the nano-carrier group. The results showed that the action of chymopapain using a pluronic-based nano-carrier system was localized around the center of the injection site instead of broad spreading, compared to that of the ordinary chymopapain group (p<0.01). This characteristic suggests a possible application to effective agents for minimally invasive spinal treatment through which disc lesions were removed selectively.

Phenolic contents and physiological properties of Pleurotus ostreatus by drying method and 30% fermented ethanol extraction for different periods (느타리버섯류의 자실체 건조 방법 및 주정 추출 기간별 페놀성 성분 함량 및 생리활성 효능 비교)

  • Yeob, So-Jin;Park, Hye-Sung;Kang, Suk-Min;Han, Jae-Gu;Lee, Kang-Hyo;Cho, Jae-Han
    • Journal of Mushroom
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    • v.14 no.4
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    • pp.215-219
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    • 2016
  • The total polyphenol and physiological activities of Pleurotus ostreatus 30% fermented ethanol using different drying methods and extraction periods were investigated. Based on the observed polyphenol content and physiological activity, freeze-drying showed better results than hot air-drying method for P. ostreatus extracted with 30% fermented ethanol for more than 15 days. The total phenolic compound content of 'Gosol' following thefreeze-drying method for 15 days showed the highest value of $0.49{\pm}0.02mg/mL$. Freeze-drying with extraction for 30 days for ASI 2344 showed the highest antioxidant activity based on the DPPH radical scavenging rate of $35.50{\pm}3.29%$. Freeze-drying 'Gosol' for 30 days resulted inthe highest anti-inflammatory and nitrite scavenging activity of $48.40{\pm}3.38%$. Our results showed that P. ostreatus is a functional food.

Studies on the characteristics of recommended soybean varieties in Korea -II. Estimates of their phenotypic and geotypic correlations and heritabilities of some traits measured (한국의 대두장려품종의 특성에 관한 연구 -II. 파종시기별로 본 실용형질간의 표현형상관 및 유전상관과 유전력)

  • M.h., Huh
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.2
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    • pp.39-45
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    • 1964
  • The phenotypic and genotypic correlations and heritabitities were calculated on 10 characters measured, using 10 native and 10 of introduced soybean varieties planted on 7 times with 15 days interval from April 15th. The genotypic correlations associated with grain yield were partitioned in to direct and indirect effects through the path coefficient analysis. The results are summarized as follows; 1. Generally high associations between characters were found, with high genotypic correlations than phenotypic, due to, probably, the fact that non segregating fixed varieties were used, and that the environmental effects were not elliminated appropreately here. Neverthless, the relative degree of association could be estimated. 2. The degree of associations of characters were different according the planting time, requiring the considerations on the specific characteristics depending on the specific planting time. 3. The introduced varieties were different with native ones in many respects, especially on the associations with stem length, stem diameter and seed weight. Here, the degree and the directions of the associations in the introduced ones were some peculier. 4. The less significant differences of characters between native varieties caused the heritability of native lower than that of introduced except the heritability of days from blooming to mature and seed weight. 5. The genetic associations of characters, measured, with grain yield were partitioned in to direct and indirect effects, calculating path coefficients. The days to bloom, stem length and stem diameter were most significantly affected the grain yield in the 5th planting of native ones.

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Study on the Illite Modification for Removal of Radioactive Cesium in Water Environment near Nuclear Facilities (원자력 시설 인근 수계에서 방사성 세슘 제거를 위한 일라이트 개질 연구)

  • Hwang, Jeonghwan;Choung, Sungwook;Shin, Woosik;Han, Weon Shik
    • Economic and Environmental Geology
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    • v.51 no.2
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    • pp.113-120
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    • 2018
  • Radioactive cesium($^{137}Cs$) can be released into the environment through severe nuclear accidents such as the Chernobyl and Fukushima, The $^{137}Cs$ is one of major monitoring radionuclides due to its chemical toxicity, ${\gamma}$ radiation and long half-life($t_{1/2}=30.2yrs$). It has been known well that illite adsorb selectively and strongly the cesium due to frayed edge sites. The quantity of the FES in the illite could be controlled by weathering processes. Therefore, this study was modified illite samples through artificial weathering in the laboratory to increase sorption efficiency for cesium. Abundant interlayer cations(i.e., K, Ca) were eluted within 1 day, while Si and Al were gradually released from the crystal structure. In addition, broad peaks of XRD indicated the occurrence of chemical weathering. The cesium sorption distribution coefficients increased up to approximately 2 times after the weathering. These results suggested that sorption capacity of illite could be enhanced for cesium through artificial weathering under low temperature.

Action modes of the anti-complementary polysaccharides purified from Arecae pericarpium (대복피로부터 정제된 보체활성화 다당의 작용양식)

  • Shin, Kwang-Soon;Cho, Hong-Yon;Sung, Ha-Chin;Yang, Han-Chul
    • Applied Biological Chemistry
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    • v.35 no.6
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    • pp.462-469
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    • 1992
  • Two kinds of complement activating (anti-complementary) polysaccharides, which were expected to be immunomodulators were purified from Arecae Pericarpium (the pericarps of Areca catechu), and their action modes have been studied. The active polysaccharides, AC-2-IIIa and AC-2-IIIc from Arecae Pericarpium showed dose-dependent anti-complementary activities on $TCH_{50}$. The anti-complementary activities of AC-2-IIIa and AC-2-IIIc in metal ion-free condition were completely decreased in comparison with control whereas in case of $Ca^{2+}$-free condition, these activities were maintained, considerably. Also AC-2-IIIa and AC-2-IIIc showed relatively potent alternative complement pathway activities. Furthermore, after incubation of the normal human serum with polysaccharide of Arecae Pericarpium in the absence of $Ca^{2+}$ ion, a cleavage of C3 in the serum was found to have occurred through immunoelectrophoresis (IEP) with anti-human C3. Also, from the results of IEP using anti-human whole serum, the ratios of the height of 3rd peak to ${\alpha}2-M$ peak by AC-2-IIIa and AC-2-IIIc proved to be $1.50{\pm}0.04$ and $1.22{\pm}0.08$, respectively. These results indicate that the modes of complement activation by AC-2-IIIa and AC-2-IIIc from Arecae Pericarpium are via both the classical pathway and the alternative pathway.

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Effect of Barley Tea on the Reduction of the Tap Water Chlorination By-Products in Top Water and Identification of Maillard Reaction Products in the Extracts of Barley Tea, Corn Tea, and Cassia tora Seed Tea Using GC/MSD (보리차 제조시 수돗물 중 염소소독부산물의 제거 여부 및 보리차.옥수수차.결명차 중 Maillard 반응 생성물 동정)

  • Lee, Soo-Hyung;Kim, He-Kap
    • Applied Biological Chemistry
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    • v.42 no.3
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    • pp.256-261
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    • 1999
  • This study was conducted to investigate the effect of barley tea with roasted grains and barley tea with a tea bag on the reduction of chlorination by-product(CBP) levels in chlorinated drinking water. Since the concentrations of six volatile compounds of eight CBPs were blow their respective detection limits after 10 minute heating, two nonvolatile CBPs dichloroacetic acid and trichloroacetic acid, and total chlorine were compared between tap water and two kinds of barley tea. No significant differences were observed in the relative changes of the amounts of the above three items, and new peaks which were not found in the original water appeared in the chromatograms of gas chromatograph/electron capture detector(GC/ECD). Thirty three organic compounds were identified in the extracts of barley tea with roasted grains, barley tea with a tea bag, corn tea, and Cassia tora seed tea which were prepared with distilled/deionized water, using gas chromatography/mass selective detection(GC/MSD). Exclusive of fatty acids, most of the compounds were aromatic compounds such as phenols, furans, and pyrroles.

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A Field Application Feasibility of Biologically Derived Substances (Naphthoquinone Derivate: NQ 2-0) for the Mitigation of Harmful Cyanobacterial Blooms (유해 남조류 제어를 위한 생물유래 살조물질 Naphthoquinone 유도체 (NQ 2-0)의 현장 적용 가능성)

  • Joo, Jae-Hyoung;Park, Chong-Sung;Choi, Hye Jeong;Lee, Heon Woo;Han, Myung-Soo
    • Ecology and Resilient Infrastructure
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    • v.4 no.3
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    • pp.130-141
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    • 2017
  • We evaluated the field application feasibility that biologically derived substances (Naphthoquinone derivate: NQ 2-0) can be used for the eco-friendly mitigation of natural harmful cyanobacterial blooms in freshwater. We conducted a 30 ton scale mesocosm experiment to investigate the effects of NQ 2-0 on biotic and abiotic factors in water collected from Gi-heung reservoir. In the mesocosm experiments, the abundance of Microcystis sp. was continuously increased in the control. However, the Microcystis sp. cell density was sharply decreased on the $10^{th}$ day. In the treatment, NQ 2-0 showed the strong and selective algicidal activity toward the target cyanobacteria (Microcystis sp.). Accordingly, the algicidal activity of NQ 2-0 compound increased gradually until $10^{th}$, $15^{th}$ days and algal biomass was decreased to 99.4 and 100 %, respectively. NQ 2-0 compound was not only selective algicidal activity but also the growth of other phytoplankton and increased the Shannon-Wiener diversity index of phytoplankton. In the mesocosm experiments, the dynamics of biotic (bacteria, heterotrophic nanoflagellate, ciliates, zooplankton) and abiotic (water temperature, dissolved oxygen, pH, conductivity, nutrients) factors remained unaffected. These results suggest that NQ 2-0 could be a selective and ecologically safe algicide to mitigate harmful cyanobacterial blooms. In addition, it is believed that NQ 2-0 will play a major role in forming a healthy aquatic ecosystem by facilitating habitat and food supply of aquatic organisms.

Synthesis and quantative structure-activity relationships on the antifungal activity of 3-phenylisoxazol and 3-phenyl-2,5-dihydro-5-isoxazolone derivatives (3-phenylisoxazole 및 3-phenyl-2,5-dihydroisoxazol-5-one 유도체의 합성과 살균활성에 관한 구조-활성관계)

  • Sung, Nack-Do;Yu, Seong-Jae;Lee, Hee-Chul
    • The Korean Journal of Pesticide Science
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    • v.5 no.4
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    • pp.20-26
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    • 2001
  • A series of new 2-benzoyl-3-phenyl-2,5-dihydroisoxazol-5-one, (A) and 3-phenyl-5-phenylcarbonyl-oxyisoxazole, (B) derivatives as substrates were synthesized and their quantitative structure-activity relationships (QSAR) analyses between the antifungal activities ($pI_{50}$) and physicochemical parameters of substituents onl the benzoyl group against resistant (RPC:95CC7303) and sensitive (SPC:95CC7105) Phytophthora blight (Phytophthora capsici,) were studied. The synthetic yield (%) and antifungal activities of (A) were higher than (B) and selectivities between the fungi were not showed. From the basis on the Hansch-Fujita analyses, the optimum width values ($(B_2)_{opt.}=ca.\;4.00{\AA}$) of the substituents on the benzoyl group were important factor in determining fungicidal activity against the two fungi. Influence of the substituents as electron withdrawing group on the fungicidal activity against RPC, but not for SPC. And tile bromo- and acetyl-substituents were contributed to higher antifungal activity against RPC and SPC from the results of Free-Wilson analyses.

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DeNOx by Hydrocarbon-Selective Catalytic Reduction on Ag-V/γ-Al2O3 Catalyst (Ag-V/γ-Al2O3 촉매상에서 탄화수소-Selective Catalytic Reduction에 의한 질소산화물 저감)

  • Kim, Moon-Chan;Lee, Cheal-Gyu
    • Applied Chemistry for Engineering
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    • v.16 no.3
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    • pp.328-336
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    • 2005
  • In order to remove the NO contained in exhaust gas by the non-selective catalyst reduction method, the catalysts were prepared by varing the loading amount of Ag and V into ${\gamma}-Al_2O_3$. The conversion of $NO_x$ using the prepared catalysts was studied by varying the temperatures, $O_2$ concentrations and $SO_2$ concentrations using. The influence of the catalyst structure on $NO_x$ conversion was studied through the analysis of the physical properties of the prepared catalysts. In the case of $AgV/{\gamma}-Al_2O_3$ catalyst, the $NO_x$ conversion was lower than that of $Ag/{\gamma}-Al_2O_3$ at higher temperatures but higher than that of $Ag/{\gamma}-Al_2O_3$ at lower temperatures. Even though $SO_2$ was contained in the reaction gas, the $NO_x$ conversion did not decrease. Based on the analysis including XRD, XPS, TPR, and UV-Vis DRS before and after the experiments, the experimental results were examined. The results indicated that, $NO_x$ conversion decreased at higher temperatures since Ag oxide could not be maintained well due to the addition of V, whereas it increased at temperatures lower than $300^{\circ}C$ due to the catalytic action of V.