• 제목/요약/키워드: pH-shifting

검색결과 40건 처리시간 0.026초

아연광산 주변 논토양에서 토양(土壤) 화학성(化學性)이 중금속의 형태(形態) 및 그 분포(分布)에 미치는 영향 (Effects of Soil Chemical Properties on the Distribution and Forms of Heavy Metals in Paddy Soils near Zine Mines)

  • 현해남;유순호
    • 한국토양비료학회지
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    • 제24권3호
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    • pp.183-191
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    • 1991
  • 본 연구는 아연광산(亞鉛鑛山) 주변의 논토양에 존재하는 Cd, Pb, Cu 및 Zn의 형태별 함량을 조사하여 중금속간의 분포(分布) 특성(特性)을 검토하였으며, 토양 화학적 성질이 이들의 형태별 함량 분포에 미치는 영향을 밝히기 위하여 수행되었다. 그 결과를 요약하면 다음과 같다. 1. 공시토양에 존재하는 Cd, Pb, Cu 및 Zn은 주로 해화물-잔류태(殘留態)로 존재하였으며, Cd와 Pb의 산화물(酸化物)-탄산염태(炭酸鹽態)와 Cu의 유기복합태(有機複合態)의 함량도 높은 편이었다. Pb와 Cu의 치환태는 소량 존재하였으며, 수용태는 Zn만 검출되었다. 2. 치환태의 분포비가 높은 토양일수록 산화물-탄산염태 및 황화물-잔류태의 분포비가 낮았다. 3. 토심이 깊어질수록 치환태 Cd 및 Zn의 분포비(分布比)는 낮아지고 항화물-잔류태의 분포비가 높아졌으며, Pb는 산화물-탄산염태의 분포비가 낮아지고 황화물-잔류태의 분포비가 높아졌다. 4. Cu는 유기물이 많은 토양일수록 Cu의 유기복합태 함량이 많았으며, Cd, Pb 및 Zn의 유기복합태는 유기물함량과 관계가 없었다. 치환태 Cd, Pb 및 Zn의 분포비는 pH가 높은 토양일수록 낮았으나, 이들의 산화물-탄산염태과 황화물-잔류태의 분포비의 합은 높았다. Pb의 산화물-탄산염태 및 황화물-잔류태의 분포비는 공시토양의 pH 전범위에서 Cd 및 Zn에 비하여 높았다.

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비체중(比體重)의 보험의학적고찰(保險醫學的考察) (A Study on the Ratio of Weight-far-Height in Insurance Medicine)

  • 임영훈
    • 보험의학회지
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    • 제2권1호
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    • pp.195-217
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    • 1985
  • A statistical analysis on the ratio of weight-for-height in insurance medicine was carried out in a total of 12,690 insured persons who were medically examined at the Honam medical department, Dong Bang life insurance company, ltd. from June, 1979 to February, 1984. The results were as follows: 1. The mean value of the ratio of weight-for-height(W/H ratio) was $102.3{\pm}11.3%$ in all males, and $105.2{\pm}103.6%$ in all females. The difference of the values between males and females showed statistical significance(P<0.001). The mean value of W/H ratio in all the insureds was $103.8{\pm}12.9%$. In each age group, the mean value of female was higher than that of male without exception(P<0.001). The mean value of both sexes in each age group showed gradual increase with age except for the age group over 50(P<0.001). 2. The incidences of the average weighted, overweighted and underweighted lives were respectively 91.6% in all males, 84.2% in all females(P<0.001); 7.9% in all males, 15.4% in all females(P<0.001); 0.5% in all males, 0.4% in all females(P>0.05). The incidences of average weighted, overweighted and underweighted lives in all the insureds were respectively 87.6%, 12.0% and 0.5%. The incidence of the average weighted lives in male in each age group was always higher than that in female with the exception of the age group below 19(P<0.001), whereas the incidence of the overweighted lives in male in each age group was always lower than that in female(P<0.05 in the age group below 19, P<0.001 in the other age groups). The incidence of average weighted lives of both sexes in each age group showed gradual decrease with age from the second to fifth decade(P<0.001), whereas the incidence of the overweighted lives of both sexes in each age group showed gradual increase with age from the second to fifth decade(P<0.001). 3. The relative frequency distribution polygons of W/H ratio of both sexes drawn in a pair on one coordinate plane revealed lying in juxtaposition each other horizontally and showed the shifting of female's polygon to male's one toward the direction of greater value of W/H ratio at a short distance which increased gradually with age. 4. Correlations between both sexes and among age groups relating to W/H ratios of the insureds seem to be a physiological phenomenon of body build and should be considered on the rating of the build. Author prepared a rating table of build based on the correlations above menthioned. Some gradients by sex and age in the rating table of build are organized; in female group, the ratings of 0, 30-50, 50-100 and 100-D are to calculate by the build with W/H ratio of 80-125%, $126{\sim}145%,\;146{\sim}165%$ and over 166% respectively in the age group of 29 or under, by the build with W/H ratio of $80{\sim}130%,\;131{\sim}150%,\;151{\sim}170%$ and over 171% respectively in the age group of $30{\sim}59$, and by the build with W/H ratio of $80{\sim}135%,\;136{\sim}155%,\;156{\sim}175%$ and over 176% respectively in the age group of 60 or over. In male group, the ratings of 0, $30{\sim}50$, 50-100, and 100-D are to calculate by the build with W/H ratio of $80{\sim}120%,\;121{\sim}140%,\;141{\sim}160%$ and over 161% respectively in all ages. Of under weighted lives, in both sexes, the ratings of 30-50 and 50-D are to calculate by the build with W/H ratio of $76{\sim}79%$ and under 75% respectively. The results of the ratings according to a rating table by author were as follows: The incidence of the ratings of 0, 30-50, 50-100 and 100-D showed no difference between male and female. The incidence of the ratings of 0(indicating the average weighted lives) showed gradual decrease with age and the incidence of the ratings of 30-50 and 50-100(indicating the overweighted lives) showed gradual increase with age. These results are thought to be considerably reasonable because the incidence of the builds in each age group is supposed to have no difference by sex and the incidence of the overweighted lives would increase with age.

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In Sacco Evaluation of Rumen Protein Degradation Characteristics and In vitro Enzyme Digestibility of Dry Roasted Whole Lupin Seeds (Lupinus albus)

  • Yu, P.;Egan, A.R.;Leury, B.J.
    • Asian-Australasian Journal of Animal Sciences
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    • 제12권3호
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    • pp.358-365
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    • 1999
  • The effects of dry roasting whole lupin seeds (lupinus albus, WLS) at 110, 130 or $150{^{\circ}C}$ for 15, 30 or 45 minutes on the in sacco rumen degradation characteristics, optimal heating conditions of time and temperature and in vitro enzyme digestibility were determined. Ruminant degradation characteristics (RDC) of crude protein (CP) of WLS were determined by in sacco technique in dairy cows. Measure ROC were soluble (S), undegradable (U), potentially degradable (D) fractions, lag time (TO) and rate of degradation (Kd) of insoluble but degradable fraction. Based on measured ROC, percentage bypass CP (%BCP) and bypass CP (BCP in g/kg, DM) were calculated. Degradability of CP was significantly reduced by dry roasting (p<0.001). The interaction of dry roasting temperature and time had significant effects on D (p<0.05), Kd (p<0.01), U (p<0.01), %BCP (p<0.001) and BCP (p<0.001) but not on S (p=0.923>0.05). With increasing time and temperature, S, D, Kd and U varied from 31.8%, 67.4%, 10.3%/h and 0.8% in the raw WLS (RWLS) to 27.1 %, 35.8%, 3.6%/h, 38.4% in $150{^{\circ}C}/45\;min$, respectively. All these effects resulted in increasing %BCP from 25.9 in RWLS to 61.0% in the $150{^{\circ}C}/45\;min$. Therefore BCP increased form 111.2 to 261.2 g/kg DM, respectively. Both %BCP and BCP at $150{^{\circ}C}/45\;min$ increased nearly 2.5 times over the RWLS. The effects of dry roasting on %BCP and BCP seemed to be linear up to the highest value tested. Although ROC had been altered by dry roasting, the In vitro perpsin-cellulase digestibility was generally unchanged. It was concluded that dry roasting was effective in shifting CP degradation from rumen to the lower gastrointestinal tract to potential reduce unnecessary N loss in the rumen. It might be of great value in successfully synchronizing the rhythms of release of nitrogen and energy in the rumen, thus achieving a more efficient fermentation of diets with high proportions of lignocellulosic resources. To determine the optimal dry roasting conditions, the digestibility of each treatment in the cows will be measured in the next trial using mobile bags technique.

A Novel Approach to the Production of Hyaluronic Acid by Streptococcus zooepidemicus

  • Kim, Sae-Jin;Park, Sung-Yurb;Kim, Chan-Wha
    • Journal of Microbiology and Biotechnology
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    • 제16권12호
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    • pp.1849-1855
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    • 2006
  • It has been shown that the initial conditions of bacterial cultivation are extremely important for the successful production of hyaluronic acid (HA) by fermentation. We investigated several parameters that affect cell growth rate and the productivity and molecular weight of hyaluronic acid--i.e., agitation speed, aeration rate, culture temperature, pH, and pressure--to determine how to optimize the production of HA by Streptococcus zooepidemicus on an industrial scale. Using a 30-1 jar fermentor under laboratory conditions, we achieved maximum HA productivity and biomass when the agitation speed and aeration rate were increased simultaneously. By shifting the temperature downward from 35$^{\circ}C$ to 32$^{\circ}C$ at key levels of cell growth during the fermentation process, we were able to obtain HA with a molecular weight of $2.8{\times}10^6$ at a productivity of 5.3 g/l. Moreover, we reproduced these optimized conditions successfully in three 30-1 jar fermentors. By reproducing these conditions in a 3-$m^3$ fermentor, we were able to produce HA with a molecular weight of $2.9{\times}10^6$ at a productivity of 5.4 g/l under large-scale conditions.

Photocatalytic Degradation of Methyl tert-Butyl Ether (MTBE): A review

  • Seddigi, Zaki S.;Ahmed, Saleh A.;Ansari, Shahid P.;Yarkandi, Naeema H.;Danish, Ekram;Oteef, Mohammed D.Y.;Cohelan, M.;Ahmed, Shakeel;Abulkibash, Abdallah M.
    • Advances in environmental research
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    • 제3권1호
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    • pp.11-28
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    • 2014
  • Advanced oxidation processes using UV and catalysts like $TiO_2$ and ZnO have been recently applied for the photocatalytic degradation of MTBE in water. Attempts have been made to replace the UV radiation by the solar spectrum. This review intends to shed more light on the work that has been done so far in this area of research. The information provided will help in crystallizing the ideas required to shift the trend from UV photocatalysis to sunlight photocatalysis. The careful optimization of the reaction parameters and the type of the dopant employed are greatly responsible for any enhancement in the degradation process. The advantage of shifting from UV photocatalysts to visible light photocatalysts can be observed when catalysts like $TiO_2$ and ZnO are doped with suitable metals. Therefore, it is expected that in the near future, the visible light photocatalysis will be the main technique applied for the remediation of water contaminated with MTBE.

Effect of Phospho-gypsum on reduction of methane emission from rice paddy soil

  • Ali, Muhammad Aslam;Lee, Chang-Hoon;Kim, Pil-Joo
    • 한국환경농학회지
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    • 제26권2호
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    • pp.131-140
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    • 2007
  • Phospho-gypsum a primary waste by-product in phosphate fertilizer manufacturing industry and a potential source of electron acceptors, such as mainly of sulfate and a trace amount of iron and manganese oxides, was selected as soil amendment for reducing methane $(CH_4)$ emissions during rice cultivation. The selected amendment was added into potted soils at the rate of 0, 2, 10, and 20 Mg $ha^{-1}$ before rice transplanting. $CH_4$ flux from the potted soil with rice plant was measured along with soil Eh and floodwater pH during the rice cultivation period. $CH_4$ emission rates measured by closed chamber method decreased with increasing levels of phospho-gypsum application, but rice yield markedly increased up to 10 Mg $ha^{-1}$ of the amendment. At this amendment level, total $CH_4$ emissions were reduced by 24% along with 15% rice grain yield increment over the control. The decrease in total $CH_4$ emission may be attributed due to shifting of electron flow from methanogenesis to sulfate reduction under anaerobic soil conditions.

Forisome based biomimetic smart materials

  • Shen, Amy Q.;Hamlington, B.D.;Knoblauch, Michael;Peters, Winfried S.;Pickard, William F.
    • Smart Structures and Systems
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    • 제2권3호
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    • pp.225-235
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    • 2006
  • With the discovery in plants of the proteinaceous forisome crystalloid (Knoblauch, et al. 2003), a novel, non-living, ATP-independent biological material became available to the designer of smart materials for advanced actuating and sensing. The in vitro studies of Knoblauch, et al. show that forisomes (2-4 micron wide and 10-40 micron long) can be repeatedly stimulated to contract and expand anisotropically by shifting either the ambient pH or the ambient calcium ion concentration. Because of their unique abilities to develop and reverse strains greater than 20% in time periods less than one second, forisomes have the potential to outperform current smart materials as advanced, biomimetic, multi-functional, smart sensors or actuators. Probing forisome material properties is an immediate need to lay the foundation for synthesizing forisomebased smart materials for health monitoring of structural integrity in civil infrastructure and for aerospace hardware. Microfluidics is a growing, vibrant technology with increasingly diverse applications. Here, we use microfluidics to study the surface interaction between forisome and substrate and the conformational dynamics of forisomes within a confined geometry to lay the foundation for forisome-based smart materials synthesis in controlled and repeatable environment.

Influence of Pressure Toasting on Starch Ruminal Degradative Kinetics and Fermentation Characteristics and Gelatinization of Whole Horse Beans (Vicia faba) in Lactating Dairy Cows

  • Yu, P.;Goelema, J.O.;Tamminga, S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제12권4호
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    • pp.537-543
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    • 1999
  • Whole horse beans (Vicia faba cv. Alfred) (WHB) were pressure toasted at different temperatures of 100, 118 and $136^{\circ}C$ for 3, 7, 15 and 30 minutes in order to determine an optimal heating conditions to increase bypass starch (BPSt) as glucose source which is usually limiting nutrient in highly producing dairy cows in the Netherlands. Starch (St) Ruminal Degradative Kinetics and Fermentation Characteristics of (SRDC) of WHB were determined using in sacco technique in 4 lactating dairy cows fed 47% hay and 53% concentrate according to Dutch dairy cow requirements. Measured characteristics of St were soluble fraction (S), potentially degradable fraction (D) and rate of degradation (Kd) of insoluble but degradable fraction. Based on measured characteristics, percentage bypass starch (BPSt) was calculated according to the Dutch new feed evaluation system: the DVE/OEB system. Pressure toasting temperatures significantly affected starch gelatinization (p<0.01). Degradability of Starch in the rumen was highly reduced by pressure toasting (p<0.01). S varied from 58.2% in the raw WHB (RWHB as a control) to 19.6% in $136^{\circ}C/15min$. S was reduced rapidly with increasing time and temperature (p<0.01). D varied from 41.8% in RWHB to 80.5% in $136^{\circ}C/15min$. D fraction was enormously increased with increasing time and temperature (p<0.01). Kd varied from 4.9%h in RWHB to 3.4%/h in $136^{\circ}C/15min$. All these effects resulted in increasing %BPSt from 29.0% in RWHB to 53.1% in $136^{\circ}C/15min$. Therefore BPSt increased from 93.5 g/kg in RWHB to 173.5 g/kg in $136^{\circ}C/15min$. The effects of pressure toasting on %BPSt and BPSt seemed to be linear up to the highest values tested. Therefore no optimal pressure toasting conditions could be determined at this stage. But among 10 treatments, The treatment of $136^{\circ}C/15min$was the best with the highest BPSt content. It was concluded that pressure toasting was effective in shifting starch degradation from rumen to small intestine to increase bypass starch.

Fusarium 균주의 배양 조건 및 생리적 조건에 따른 T-2 toxin의 생성 조건 (Cultural and Physiological Conditions for T-2 Toxin Production by Fusarium sp.)

  • 홍성희;양규환
    • 미생물학회지
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    • 제36권2호
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    • pp.91-96
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    • 2000
  • 불와전 균류인 Fusarium s^g pp.를 이용하여 여러 가지 배양조건과 생리적 영향에 따른 균주의 성장 및 T-2 toxin의 생성에 관하여 고찰하였다. T-2 toxin 의 검출방법은 thin layer chromatography (TCL) 법과 미생물학적 검출방법을 사용하였다. 고체 배지의 경우 횐옥수수 가루(Quaker사 제품)베지에서 다른 곡물보다 많은 양의 T-2 toxin이 생성되었으며,비교적 깨끗한 T-2 toxin이 정제되었다. 이 경우 배지 100g당 약 700 mg의 T-2 toxin이 생성되었으며, 그중 약 30%정도가 깨끗한 결정으로 정제되었다. 고온(20-$25^{\circ}C$)에서는 생장은 많았으나, T-2 toxin의 생성은 적었으며, 저온(10-$15^{\circ}C$)에서는 비교적 생장이 적었지만, T-2 toxin의 생성이 많았고, 젖당, 글리세롤, 솔비톨의 경우는 적었다. 유일 탄소원으로 구연산과 초산은 이용하지 못하였으며, 녹발의 경우 생장은 많았으나 T-2 toxin의 생성양은 적었다. 질소원의 경우 $NaNO_2$를 제외하고는 $(NH_4)_2NO_4$, $NH_4Cl_3$, $NH_4NO_3$, $KNO_3$ 를 거의 동일하게 이용하였다. 초기 pH값에 생성과 균주의 성장은 pH4.0-5.0일 경우 최적을 나타냈으며 ph6.0이상에서는 성장도 저하되고, T-2 toxin생성도 적었다. 회전속도에 따른 T-2 toxin 생성과 균주의 성장을 보면 회전속도가 속돠 증가함에 따라 균주의 생장과 T-2 toxin 생성량이 모두 증가하였다. $15^{\circ}C$에서 7일간 배양 후, $25^{\circ}C$로 옮겨 7일간 배양하여, toxin의 생성을 보면, $15^{\circ}C$에 7일간 배양했을 때보다 T-2 toxin양이 적었다. 이는 생성되었던 T-2 toxin이 분해되었음을 보여주는 것이다. 이상의 결과를 볼 때 T-2 toxin 대사 경로는 온도에 의한 효소 억제 또는 효소 유지 시스템에 의해 조절되는 것이라고 생각할 수 있다.

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카르복시 말단 유비퀴틴 가수분해 효소 활성 보유 PPPDE superfamily member인 Schizosaccharomyces pombe Sdu1의 열 스트레스에 대한 방어적 역할 (Defensive roles of Sdu1, a PPPDE superfamily member with ubiquitin C-terminal hydrolase activity, against thermal stress in Schizosaccharomyces pombe)

  • 한희;허태영;류인왕;김경훈;임창진
    • 미생물학회지
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    • 제51권4호
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    • pp.319-328
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    • 2015
  • Schizosaccharomyces pombe $sdu1^+$ 유전자는 PPPDE superfamily member에 속하는 탈유비퀴틴화 효소인 Sdu1을 엔코딩한다. 이전 연구에서, $sdu1^+$ 유전자 포함 재조합 플라스미드 pYSTP를 사용하여 Sdu1이 카르복시 말단 유비퀴틴 가수분해 활성을 보유한다는 사실이 입증된 바 있다. 본 연구에서는, 높은 배양 온도에 대한 Sdu1의 열내성적 역할이 검토되었다. 온도 천이 실험에서, pYSTP 포함 S. pombe 세포들이 37도나 42도로 천이한 후에 벡터 대조 세포들보다 훨씬 더 잘 성장하였다. 37도나 42도로 천이 한 후 6시간 배양한 pYSTP 포함 S. pombe 세포들이 벡터 대조 세포들보다 낮은 활성산소종 수준을 나타내었다. pYSTP 포함 S. pombe 세포들이 온도 천이와 관계없이 벡터 대조 세포들보다 다소 낮은 일산화질소 수준을 나타내었다. pYSTP 포함 S. pombe 세포들이 벡터 대조 세포들보다 훨씬 높은 총 글루타치온 수준을 나타내었다. 온도천이 후의 총 수퍼옥시드 디스무타아제 및 글루타치온 과산화효소 활성들이 pYSTP 포함 S. pombe 세포들에서 더 높은 것으로 측정되었다. 요약하면, S. pombe Sdu1은 활성산소종과 일산화질소 수준은 낮추고, 총 글루타치온, 총 수퍼옥시드 디스무타아제 및 글루타치온 과산화효소 수준들은 증가시킴으로써 높은 배양 온도에 대한 열내성적 역할을 나타낸다.