• 제목/요약/키워드: Concentration Gradient

검색결과 583건 처리시간 0.027초

HPLC-UV 방법을 이용한 향부자 분석법 개발과 국산 및 중국산 향부자의 패턴비교 (Development of Content Analysis for Cyperus rotundus by HPLC-UV and a Comparison between Chinese and Domestic Cyperi Rhizoma)

  • 서지윤;김진아;김성건;유정;황완균
    • 약학회지
    • /
    • 제56권5호
    • /
    • pp.280-287
    • /
    • 2012
  • A high-performance liquid chromatography (HPLC) combined with ultraviolet (UV) method for the simultaneous determination of ${\alpha}$-cyperone and nootkatone was developed for the quality control of Cyperus rotundus Linne. The separation was performed on a KR100-$5C_{18}$ ($4.6{\times}250mm$) column, and an elution gradient composed of methanol and water with a flow-rate of 1.0 ml/min. Detection wavelength was set at 254 nm. The optimum extraction for the detection of the ${\alpha}$-cyperone and nookatone was achieved by ultrasonic with methanol for an hour. Two marker compounds ${\alpha}$-cyperone and nootkatone in Cyperi Rhizoma showed good linearity ($R^2$ >0.999) in the concentration range of $12.5{\mu}g/ml$ to $200{\mu}g/ml$. The developed method provided satisfactory precision and accuracy with overall intra-day and inter-day variations of 0.04~1.23% and 0.08~0.68%, respectively, and the overall recoveries of 97.45~105.58% for the two compounds analyzed. Additionally, a difference was observed in the cluster analysis and principal component analysis between Cyperi Rhizoma in Korea and China. The result demonstrated that the principal component analysis is useful to distinguish between Cyperi Rhizoma in Korea and China.

저결함 압전수정의 성장과 결함분석 (Growth of Low Defect Piezo-quartz and Defect Analysis)

  • 이영국;박로학
    • 한국결정학회지
    • /
    • 제8권1호
    • /
    • pp.26-32
    • /
    • 1997
  • 수열법을 이용하여 압전수정을 성장하고 각종 성장결함을 분석하였다. 4 중량퍼센트 NaOH, 성장온도 $340-360^{\circ}C$, 온도구배 $20-40^{\circ}C$의 성장조건에서 (0001)방향의 ZY 종자결정, 합성수정을 원료로 하였을 경우 성장속도는 0.25-0.65 mm/day 였다. 원료로써 합성수정을 사용하고 저전위 종자결정 위에서 수평 종자결정 배치법으로 성장된 압전수정의 전위밀도는 20.0개/$cm^2$, 에치채널 밀도는 5.0개/$cm^2,\;10\mu$ 이상의 함유물 농도는 2.4개/$cm^3$, 알파값은 0.019였으며, IEC 758규격에 의한 등급분류는 에치채널 밀도 1등급, 함유물 농도 Ia등급, 알파값 A등급이었다.

  • PDF

Roughness and micro pit defects on surface of SUS 430 stainless steel strip in cold rolling process

  • Li, Changsheng;Zhu, Tao;Fu, Bo;Li, Youyuan
    • Advances in materials Research
    • /
    • 제4권4호
    • /
    • pp.215-226
    • /
    • 2015
  • Experiment on roughness and micro pit defects of SUS 430 ferrite stainless steel was investigated in laboratory. The relation between roughness and glossiness with reduction in height, roll surface roughness, emulsion parameters was analyzed. The surface morphology of micro pit defects was observed by SEM, and the effects of micro pit defects on rolling reduction, roll surface roughness, emulsion parameters, lubrication oil in deformation zone and work roll diameter were discussed. With the increasing of reduction ratio strip surface roughness Ra(s), Rp(s) and Rv(s) were decreasing along rolling and width direction, the drop value in rolling direction was faster than that in width direction. The roughness and glossiness were obtained under emulsion concentration 3% and 6%, temperature $55^{\circ}C$ and $63^{\circ}C$, roll surface roughness $Ra(r)=0.5{\mu}m$, $Ra(r)=0.7{\mu}m$ and $Ra(r)=1.0{\mu}m$. The glossiness was declined rapidly when the micro defects ratio was above 23%. With the pass number increasing, the micro pit defects were reduced, uneven peak was decreased and gently along rolling direction. The micro pit defects were increased with the roll surface roughness increase. The defects ratio was declined with larger gradient at pass number 1 to 3, but gentle slope at pass number 4 to 5. When work roll diameter was small, bite angle was increasing, lubrication oil in micro pit of deformation zone was decreased, micro defects were decreased, and glossiness value on the surface of strip was increased.

현미입(玄米粒) 내의 칼슘, 인, 철, 비타민$B_1$$B_2$의 분포에 관한 연구 (Radial Distribution of Calcium, Phosphorus, Iron, Thiamine and Riboflavin in the Degermed Brown Rice Kernel)

  • 김성곤;최홍식
    • 한국식품과학회지
    • /
    • 제11권2호
    • /
    • pp.122-125
    • /
    • 1979
  • 배아를 제거한 현미(품종 : 아끼바레 및 밀양 23호)를 중량비로 약 $5{\sim}6{\;}%$씩 계속 5번 나누어 제거후 각 가루획분, 잔여 미립 및 현미의 칼슘, 인산, 철분, 비타민 $B_1$$B_2$를 정량하여 이들 성분의 분포를 살펴보았다. 처음 획분(현미를 $5{\sim}6%$ 도정한 가루)은 현미 자체보다 칼슘 및 인산이 8배, 철분이 4배, 비타민 $B_1$이 3배, 비타민 $B_2$가 4배 많았다. 이들 성분은 미립외부로부터 중심으로 갈수록 그 함량이 적었다. 인산 및 비타민 $B_1$의 분포양상은 두 품종간에 차이가 없었으나 밀양 23호는 아끼바레에 비하여 칼슘 및 비타민 $B_1$의 함량은 중심으로 갈수록 급격히 감소한 반면 철분은 오히려 균일하게 분포되어 있었다.

  • PDF

NaCl이 황백화된 보리(Hordeum vulgare L.) 잎의 녹화에 미치는 영향 (The Effect of NaCl on the Greening of Etiolated Leaves of Barely (Hordeum vulgare L.) Seedings)

  • 정화숙;임영진;송승달;노광수;송종석;박강은
    • 한국환경과학회지
    • /
    • 제11권10호
    • /
    • pp.1023-1030
    • /
    • 2002
  • The effects on photosynthesis of NaCl(0, 0.2, 0.4, 0.6, 0.8 or 1.0 M) were examined in etiolated barley seedlings. Chlorophyll(Chl) a, Chl b and carotenoid contents, Chl a fluorescence and quenching coefficients of Chl fluorescence have been determined in the primary leaves of etiolated barley seedlings cultivated under low light(60 $\mu$$m^{-2}\;s^{-1}$). Chl a, b, and carotenoid contents were decreased remarkably in comparison with the control at 0.4 M NaCl. However, the value of Fo and Fv were decreased at 0.6 M NaCl and the ratio of Fv/Fm were deceased at 1.0 M NaCl. Chlorophyll synthesis was seriously inhibited from 0.4 M NaCl, and the photosynthetic electron transport system was inhibited from 0.6 M NaCl. Quantum of photosystem II reaction center was inhibited at 1.0 M NaCl. The effects of NaCl on the Chl content were raised in a 6 hrs, but the effects of NaCl on the value of Fo, Fv and Fv/Fm were raised in 30 hrs. The value of qP was decreased in comparison with the control at all concentrations, but there was a small change in the value qE. These results provide evidence that NaCl inhibited effects of various concentration of NaCl were inhibited quinone redox, however, proton gradient between thylakoid membranes was little damaged.

Cometabolism degradation of lignin in sequencing batch biofilm reactors

  • Kuang, Faguo;Li, Yancheng;He, Lei;Xia, Yongqiu;Li, Shubai;Zhou, Jian
    • Environmental Engineering Research
    • /
    • 제23권3호
    • /
    • pp.294-300
    • /
    • 2018
  • Cometabolism technology was employed to degrade lignin wastewater in Sequencing Batch Biofilm Reactor. Cometabolic system (with glucose and lignin in inflow) and the control group (only lignin in inflow) were established to do a comparative study. In contrast with the control group, the average removal rates of lignin increased by 14.7% and total oarganic carbon increased by 32% in the cometabolic system with glucose as growth substrate, under the condition of 5 mg/L DO, $0.2kgCOD/(m^3{\cdot}d)$ lignin and glucose $1.0kgCOD/(m^3{\cdot}d)$. Functional groups of lignin are degraded effectively in cometabolic system proved by fourier transform infrared spectroscopy and Gas Chromatography-Mass Spectrometer, and the degradation products were amides (mainly including acetamide, N-ethylacetamide and N, N-diethylacetamide), alcohols (mainly including glycerol and ethylene glycol) and acids. Meanwhile, results of Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis showed great differences in microbial population richness between cometabolic system and the control group. The Margalef's richness index and Shannon-Wiener's diversity index of microorganism in cometabolic system were 3.075 and 2.61, respectively. The results showed that extra addition of glucose, with a concentration of 943 mg/L, was beneficial to lignin biodegradation in cometabolic system.

배아를 제거한 현미립내의 무기질의 분포 (Distribution of Minerals within the Degermed Brown Rice Kernel)

  • 송보현;김동연;김성곤;김용두;최갑성
    • Applied Biological Chemistry
    • /
    • 제31권2호
    • /
    • pp.162-168
    • /
    • 1988
  • 배아를 제거한 일반계 및 다수계 각 3품종을 도정하고, 도정분회 및 잔유립의 무기질 함량을 분석하였다. 분회 I (무게비로 약 4.4%)은 현미에 비하여 나트륨이 14.8배, 인이 5.7배, 칼륨과 철이 5.4배, 마그네슘이 4.2배, 칼슘이 3.8배, 망간이 3.7배, 구리가 3.6배, 아연이 2.3배 높았다. 무기질의 농도는 잔유립에서 가장 낮았으며, 잔유립의 무기질 함량은 현미 자체보다 낮았다. 무기질 중 나트륨의 농도 구배가 가장 심하였고 철은 비교적 균일하게 분포되어 있었다.

  • PDF

분말야금법으로 제작한 NiAl합금의 기계적성질 및 형상기억특성 (Mechanical Properties and Shape Memory Characteristics of NiAl Alloys by Powder Metallurgy)

  • 한창석;진성윤;권혁구
    • 한국재료학회지
    • /
    • 제30권5호
    • /
    • pp.231-238
    • /
    • 2020
  • The composition of martensite transformation in NiAl alloy is determined using pure nickel and aluminum powder by vacuum hot press powder metallurgy, which is a composition of martensitic transformation, and the characteristics of martensitic transformation and microstructure of sintered NiAl alloys are investigated. The produced sintered alloys are presintered and hot pressed in vacuum; after homogenizing heat treatment at 1,273 K for 86.4 ks, they are water-cooled to produce NiAl sintered alloys having relative density of 99 % or more. As a result of observations of the microstructure of the sintered NiAl alloy specimens quenched in ice water after homogenization treatment at 1,273 K, it is found that specimens of all compositions consisted of two phases and voids. In addition, it is found that martensite transformation did not occur because surface fluctuation shapes did not appear inside the crystal grains with quenching at 1,273 K. As a result of examining the relationship between the density and composition after martensitic transformation of the sintered alloys, the density after transformation is found to have increased by about 1 % compared to before the transformation. As a result of examining the relationship between the hardness (Hv) at room temperature and the composition of the matrix phase and the martensite phase, the hardness of the martensite phase is found to be smaller than that of the matrix phase. As a result of examining the relationship between the temperature at which the shape recovery is completed by heating and the composition, the shape recovery temperature is found to decrease almost linearly as the Al concentration increases, and the gradient is about -160 K/at% Al. After quenching the sintered NiAl alloys of the 37 at%Al into martensite, specimens fractured by three-point bending at room temperature are observed by SEM and, as a result, some grain boundary fractures are observed on the fracture surface, and mainly intergranular cleavage fractures.

LC-MS/MS를 이용한 계지복령환(桂枝茯苓丸)의 동시분석 및 항산화 효능 연구 (Quantitative Analysis and Antioxidant Effects of Gyejibokryeong-hwan)

  • 서창섭;김온순;신현규
    • 생약학회지
    • /
    • 제45권3호
    • /
    • pp.240-248
    • /
    • 2014
  • Gyejibokryeong-hwan (GJBRH) has been used for treatment of patients with climacteric syndrome. In this study, an ultra-performance liquid chromatography-electrospray ionization-mass spectrometer (UPLC-ESI-MS) method was established for the simultaneous quantification of seven marker compounds in GJBRH extract. In addition, we assessed the antioxidant effects of GJBRH. All analytes were separated by gradient elution using two mobile phases on a UPLC BEH $C_{18}$ column and maintained at $45^{\circ}C$. The antioxidant activities of GJBRH were evaluated by measuring free radical scavenging activities on 2,2'-azinobis-3-ethyl-benzothiazoline-6-sulfonic acid (ABTS) and 1-1-diphenyl-2-picrylhydrazyl (DPPH). The inhibitory effects on low-density lipoprotein (LDL) oxidation were evaluated by the formation of thiobarbituric acid relative substances (TBARS) and relative electrophoretic mobility (REM). Regression equations of the seven compounds were acquired with $r^2$ values ${\geq}0.9988$. The amounts of the seven compounds, amygdalin, albiflorin, paeoniflorin, coumarin, cinnamic acid, cinnamaldehyde, and paeonol in GJBRH water extract were 21.71, 2.16, 17.17, 1.97, 0.40, 0.78, and 3.42 mg/g, respectively. The GJBRH showed the radical scavenging activity in a dose-dependent manner. The concentration required for 50% reduction ($RC_{50}$) against ABTS and DPPH radicals were $54.18{\mu}g/mL$ and $79.53{\mu}g/mL$. Furthermore, GJBRH reduced the oxidation properties of LDL induced by $CuSO_4$.

An Estimation of the New Production in the Southern East Sea Using Helium Isotopes

  • Kim, Kyung-Ryul;Hahm, Do-Shik
    • Journal of the korean society of oceanography
    • /
    • 제36권1호
    • /
    • pp.19-26
    • /
    • 2001
  • The biological pump is one of the important pumping mechanisms absorbing CO$_2$ from the atmosphere into the ocean and can be quantified by estimating new production. New production in the open ocean mostly depends on the supply of nitrate from the water below the mixed layer. While nitrate is affected by many biological processes, the helium isotope ($^3$He) is inert and has very simple physical properties. Using the $^3$He flux and the relation between $^3$He and NO${_3}\;{^-}$- within the thermocline, the nitrate flux supporting new production was estimated in the southern East Sea. The average ${\delta}^3$He within the mixed layer was -14$%_o$ and -l5.4$%_o$ in the winter and autumn, respectively. Through the year excess $^3$He occurs in the mixed layer except for a slight depletion of -17$%_o$ in summer. The $^3$He flux of 13$%_o$md$^{-1}$ associated with the concentration gradient at the air-sea interface was calculated from the product of the piston velocity and the excess $^3$He. Tritium decay within the mixed layer could support only 2$%_o$md$^{-1}$ of the flux. Thus, the remaining 11$%_o$md^{-1}$ could be attributed to the flux of tritiugenic $^3$He from the water below the mixed layer. Nitrate and $^3$He were positively correlated within the thermocline layer with the slope of 0.21 ${\mu}$mol kg$^{-1}$ $%_o\;^{-1}$. The annual nitrate flux estimated from the upward flux of $^3$He and the NO$_{3}\;{^-}$-$^3$He relation was 0.8${\pm}$0.2 mol(N) m$^{-2}$yr$^{-1}$. This flux corresponds to an annual new production of 64 g(C) m$^{-2}$yr$^{-1}$, which is consistent with that in the north-west Pacific.

  • PDF