• 제목/요약/키워드: pH level

검색결과 4,803건 처리시간 0.029초

물리, 화학적 처리방법에 의한 염색폐수의 색도제거에 관한 연구 (A Study on the Reduction of Color in Dye Wastewaters by Physico-chemical Processes)

  • 이준석;김민호;김영규
    • 한국환경보건학회지
    • /
    • 제19권3호
    • /
    • pp.29-35
    • /
    • 1993
  • This study was performed to obtain optimal conditions for reduction of color in dye wastewaters using coagulation-sedimentation processes with redox reactions. The reduction of color as well as organic matters variation was observed after coagulation-sedimentation processes using FeSO$_4$ $\cdot$ 7H$_2$O and NaOCl. Coagulation-redox reaction was done with the dose of Coagulant and oxidant at various pH values. Redox reaction was done through jar-mixing and aeration. The results of study were as follows: 1. In the coagulation-sedimentation processes using FeSO$_4$ $\cdot$ 7H$_2$O, color reduction was heigher at pH 3. With variance of dosage of FeSO$_4$ $\cdot$ 7H$_2$O, color reduction was higher at 250 mg/l. When coagulation-sedimentation using FeSO$_4$ $\cdot$ 7H$_2$O 250 mg/l was added at pH 3, the reduction of color, COD$_{Mn}$, and COD$_{Cr}$ showed 47.6%, 21.3% and 22.1%, respectively. 2. When NaOCI was added at level of 100 ppm in raw wastewater at pH 3, the reduction of color, COD$_{Mn}$, and COD$_{Cr}$ showed 30.2%, 5.5% and 6.2%, respectively. 3. After coagulation-sedimentation processes by addition of FeSO$_4$ $\cdot$ 7H$_2$O, when NaOCl was added at level of 250 mg/l in supernant, color reduction was 47.8% in aeration and 37.5% in jar-mixing. 4. Color reduction by aeration was higher than that by jar-mixing.

  • PDF

EFFECTS OF LYSINE LEVEL AND NA+K-CI RATIO ON LUSINE-ARGININE ANTAGONISM, BLOOD pH, BLOOD ACID-BASE PARAMETERS AND GROWTH PERFORMANCE IN BROILER CHICKS

  • Kim, H.W.;Han, I.K.;Choi, Y.J.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제2권1호
    • /
    • pp.7-16
    • /
    • 1989
  • To determine the effect of sodium plus potassium to chloride ratio and lysine level on blood pH, blood acid-base parameters, lysine-arginine antagonism and growth performance, four hundred and thirty two chicks of 3 days age were used in a completely randomized $3{\times}3$ factorial experiment. Variables contained three levels of lysine (0.8, 1.2 and 1.6%) and dietary electrolyte (100, 200 and 300 mEq/kg). Birds fed 200 mEq/kg and electrolyte had the best growth rate and feed efficiency, followed by those fed 300 mEq/kg and 100 mEq/kg electrolyte. It is proposed that high levels of dietary electrolyte may improve the growth of chicks fed diets containing excess lysine by increasing lysine catabolism. High or low levels of lysine and dietary electrolyte resulted in higher mortality than those of optimum level (1.2%) of lysine and 200 mEq/kg of electrolyte balance. When the electrolyte level was increased, the pH, $pCO_2$, base excess, $HCO_3{^-}$ and total $CO_2$ of blood plasma were increased. The utilization of nutrients was changed when the electrolyte and lysine were manipulated. Plasma chloride tended to be greater in chicks receiving high chloride diet and was the highest in chicks fed the high lysine diet. Plasma sodium and potassium were unaffected by dietary lysine. Diet containing high lysine decreased the level of arginine and excess dietary electrolyte increased arginine level in plasma. It may be concluded that cation supplementation tended to alleviate the lysine-arginine antagonism but chloride exacerbated. Tibia bone length and ash contents were significantly affected by electrolyte balance and lysine level.

석회시용량과 시용시기가 경작지 토양산도 변화와 잎담배 수량 및 품질에 미치는 영향 (Effect of Lime Amount and Application Time on Soil pH Change, Yield, and Quality of Leaf Tobacco)

  • 정훈채;김용연;황건중
    • 한국연초학회지
    • /
    • 제22권1호
    • /
    • pp.61-70
    • /
    • 2000
  • This study was carried out to improve the tobacco field condition and to determine the effect of lime amount and application time on soil pH, yield, and quality of leaf tobacco. Lime was applied to the tobacco field by determined amounts according to different pH level. The changes of soil pH, growth of tobacco, yield, and quality of KF109 and Br21 tobacco were surveyed by time lapse. The target pH value in tobacco field soil can be reached at 6 weeks after lime application, and then the soil pH was lowered slightly after that time. The lime amount needed to reach target pH was decreased 40 % in the same tobacco field after 1 year. Though the initial growth rate of flue-cured tobacco in the field of pH 7.0 was lower than that of conventional tobacco field, the field of pH 7.0 showed the highest yield after the maximum growth stage. The quality of cured leaf tobacco in the field of pH 7.0 applied lime at spring season was slightly lowered compared with that in conventional. This results indicated that the best pH condition in tobacco field for the best tobacco growth was 6.5 and the proper time of lime application was fall season of previous year by application of the whole quantity.

  • PDF

원수 수질특성과 응집제 염기도에 따른 응집 pH 및 주입량의 영향 (The Effects of pH and Dosages According to Qualities of Raw Waters and Basicity of Coagulants)

  • 박노백;이범;전동걸;이영주;전항배
    • 상하수도학회지
    • /
    • 제24권5호
    • /
    • pp.581-593
    • /
    • 2010
  • The objectives of this study were to investigate the effects of raw water pH and basicity of coagulants on turbidity removal with several raw waters having different level of turbidity, alkalinity and pH. Raw waters were sampled from M, S and B water treatment plants(WTP) located at Miryang, Nakdong, Han river, respectively. Six coagulants which have different levels of basicity and aluminum contents were used for this evaluation. High basicity of the coagulant helped to properly control coagulation processes for treating turbid and low alkali raw water. It was difficult for operators to determine optimum coagulant dose for high basicity coagulants, since residual turbidity tended to decrease continuously as coagulant dose increased. Turbidity removal efficiencies with high basicity coagulants(E and F) were higher than the other coagulants at ambient pH for the M WTP. Turbidity removal efficiencies, however, at adjusted pH 7.0 showed similar among six coagulants. Residual turbidity kept low at excess dosages with high basicity coagulants. Optimum coagulant dosages at adjusted pH 7.0 showed higher than those at ambient pH in M WTP. On the contrary in B WTP, optimum coagulant dosage at ambient pH were higher than that at adjusted pH 7.0.

Geochemical speciation of dissolved heavy metals in acid mine drainage: effects of pH and total concentration

  • Jung, Hun-Bok;Yun, Seong-Taek;Kwon, Jang-Soon;So, Chil-Sup;Lee, Pyeong-Koo
    • 한국지하수토양환경학회:학술대회논문집
    • /
    • 한국지하수토양환경학회 2003년도 추계학술발표회
    • /
    • pp.404-408
    • /
    • 2003
  • In this study, we examined the influences of pH and total concentration on the speciation of heavy metals (Cd, Cu, Zn) in acid mine drainage. Their labile concentrations were analyzed by Anodic Stripping Voltammetry (ASV) at both natural pH and adjusted pHs (from 2 to 8). We obtained regression equations for predicting labile concentrations as a function of the water pH and contamination level (total dissolved metal concentration). Our data show that labile Cu depends on both the total concentration and pH, while labile Cd and Zn concentrations are controlled mainly by their total concentration rather than pH. Therefore, the pH variation of AMD may significantly change the toxicity and bioavailability especially of Cu, owing to its speciation change.

  • PDF

영월과 신림에 있어서 소나무낙엽의 분해와 Microbial Population 의 소장 비교 (Comparison of the Pine Litter Decompositon and Microbial Population Change at Youngwal with Those at Sinlim)

  • Chang, Nam-Kee;Lee, Yong-Woo m
    • The Korean Journal of Ecology
    • /
    • 제9권1호
    • /
    • pp.9-18
    • /
    • 1986
  • The decomposition of litters of Pinus densiflora and the growth of microbial populations in a calcareous region, Youngwal were compared with those in a noncalcareous region, Sinlim. The decay rate of litter in Pinus densiflora in Youngwal was 0.128 and that in Sinlim was 0.096. The differences in the populations of soil bacteria and total microorganisms between the two regions were signficant at the 5% level, but that of fungi and actinomycetes was not at that level. The differences in the content of calcium and pH value of soil between the two regions were significant at the 1% level. The excessive content of calcium became to increase pH value, in turn the high pH decreased the content of available phosphorus in soil. The vertical distribution of the content of available phsophorus was consistent with that of the populations of fungi and actinomycetes in Youngwal.

  • PDF

임지이용이 계류의 수질변화에 미치는 영향 (A Change of the Stream Water Quality by Forest Land Use)

  • 마호섭;구소영
    • 한국환경복원기술학회지
    • /
    • 제5권6호
    • /
    • pp.43-48
    • /
    • 2002
  • 순수산림으로 존재하고 있는 소나무림과 밤나무재배 등으로 임지를 이용하고 있는 밤나무림 그리고 밤나무 재배 후의 휴경지 등 3개 조사구(소나무, 밤나무I, 밤나무II임분)에서 비점오염원으로의 영향을 살펴보기 위해 계류수를 조사하여 임지이용에 따른 수질변화를 분석하여 얻은 결과를 요약하면 다음과 같다. 1. 세 임분의 계류수 pH는 소나무임분(pH 6.59)>밤나무II임분(pH 6.53)>밤나무I임분(pH 6.47)계류수 순으로 나타났다. 2. 전기전도도는 밤나무I임분>소나무임분>밤나무II임분 계류수의 순으로 높게 나타났다. 3. 양이온은 세 임분의 계류수 모두 $Ca^{2+}$, $Na^{2+}$, $Mg^{2+}$, $K^+$, ${NH_4}^+$의 순으로 높게 나타났다. 4. 음이온은 소나무임분과 밤나무II 임분 계류수에서는 ${SO_4}^{2-}$, $Cl^-$, ${NO_3}^-$의 순으로 높게 나타났고, 밤나무I 임분 계류수에서는 ${NO_3}^-$, ${SO_4}^{2-}$, $Cl^-$의 순으로 높게 나타나 차이를 보였다. 5. 소나무, 밤나무II임분 계류수는 pH, ${NH_4}^+$, ${NO_3}^-$, $Cl^-$, ${SO_4}^{2-}$이 먹는 물 수질기준 범위내에 있었다. 그러나 밤나무I임분 계류수에서 5항목 중 ${NO_3}^-$는 먹는 물 수질기준을 넘어서는 범위에 있어 임지이용에 따른 하류수질의 오염이 우려된다. 따라서 이러한 상류지역에서 오염원 차단을 위한 수질정화시설 등의 대책이 마련되어야 할 것으로 사료된다.

Role of Centromere Protein H and Ki67 in Relapse-free Survival of Patients after Primary Surgery for Hypopharyngeal Cancer

  • Wang, Jun-Xi;Zhang, Ying-Yao;Yu, Xue-Min;Jin, Tong;Pan, Xin-Liang
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권3호
    • /
    • pp.821-825
    • /
    • 2012
  • Purpose: Centromere protein H (CENP-H) and Ki67 are overexpressed in some malignancies, but whether they are predictors of survival after primary resection for hypopharyngeal squamous cell carcinoma (HSCC) remains unknown. Methods: We assessed immunohistochemical expression of CENP-H and Ki67 in 112 HSCC specimens collected between March 2003 and March 2005 for analysis by clinical characteristics. The Kaplan-Meier method was used to analyze relapse-free survival and logistic multivariate regression to determine risk factors of relapse-free survival. Cholecystokinin octapeptide assays and flow cytometry were used to examine cell proliferation and apoptosis after siRNA inhibition of CENP-H in HSCC cells. Results: Overall, 50 (44.6%) HSCC specimens showed upregulated CENP-H expression and 69 (61.6%) upregulated Ki67. An increased CENP-H protein level was associated with advanced cancer stage and alcohol history (P=0.012 and P=0.048, respectively) but an increased Ki67 protein level only with advanced cancer stage (P=0.021). Increased CENP-H or Ki67 were associated with short relapse-free survival (P<0.001 or P=0.009, respectively) and were independent predictors of relapse-free survival (P=0.001 and P=0.018, respectively). siRNA knockdown of CENP-H mRNA inhibited cell proliferation and promoted cancer cell apoptosis in vitro. Conclusions: Upregulated CENP-H and Ki67 levels are significantly associated with short relapse-free survival in HSCC. These factors may be predictors of a relapsing phenotype in HSSC cases.

Effect of Soil Salinity on Nitrogen Mineralization of Livestock Manure Compost in Salt-Affected Coastal Soils

  • Kim, Jung-Hyun;Shim, Myung-Yong;Moon, Tae-Il;Kim, Seung-Hwan;Shin, Kook-Sik;Sonn, Yeon-Kyu;Chung, Doug-Young;Lee, Sang-Eun
    • 한국토양비료학회지
    • /
    • 제47권3호
    • /
    • pp.199-204
    • /
    • 2014
  • We conducted a short-term incubation experiment in order to understand the effect of the salinity of reclaimed coastal soils on nitrogen mineralization of livestock manure compost (LMC). Two soils with the same soil texture but different EC levels were collected from the same field. These samples were treated with 0%, 1%, 2%, and 3% of LMC by weight basis and incubated at $25^{\circ}C$ to observe changes in inorganic N contents, pH, and dehydrogenase activity with respect to time. As a result, regardless of the soil EC level, as the LMC increased, the total content of the inorganic N ($NH_4{^+}+NO_3{^-}$) increased. Difference in the soil EC level did not affect N mineralization of LMC greatly. The soil EC had negligible effect on the dehydrgenase activity as with the case of inorganic nitrogen. The $NH_4{^+}$ contents remained very low throughout the experimental period starting from the first week of incubation. We believe this is due to the high pH level (pH 7.9 and pH 8.3) of the original soils leading to ammonia volatilization. On the other hand the $NO_3{^-}$ content maintained high level as the LMC treatment level increased and reached maximum at the third week. The pH of the soil during incubation period decreased as the $NO_3{^-}$ contents increased and increased slightly after three weeks. The rise of pH level is believed to be from the $NO_3{^-}$ absorption for immobilization by microbes. In conclusion, the high soil $EC_{1:5}$ level of $12dS\;m^{-1}$ conducted in this experiment did not affect the growth in terms of soil microbes involved in N mineralization of LMC.

인공산성우(人工酸性雨)가 몇 침엽수종(針葉樹種)의 종자발아(種子發芽)와 묘목생장(苗木生長)에 미치는 영향(影響)(1) (Effects of Artificial Acid Rain on Seed Germination and Seedling Growth of Several Conifers(1))

  • 김갑태
    • 한국산림과학회지
    • /
    • 제80권2호
    • /
    • pp.237-245
    • /
    • 1991
  • 인공산성우처리가 몇 침엽수종의 발아와 묘목생장에 미치는 영향을 알아보고자, 혼합토양을 채운 polt에 5 수종의 종자를 파종하고 황산을 지하수로 묽힌 pH 3.0, 4.0 및 5.0의 인공산성우와 지하수를 주 3회, 매회 5mm씩 1990년 4월 초순부터 10월 초순까지 처리하였으며, 발아율 및 생장을 측정하여 처리간 비교분석한 결과는 다음과 같다. 1. 낙엽송과 종비나무는 pH 5.0 처리구에서, 젓나무와 삼나무는 대조구에서, 구상나무 는 pH 3.0 처리구에서 각각 발아율 및 득묘율이 가장 높았다. 2. 묘고생장에 있어서 낙엽송에서는 처리간 고도의 통계적 유의성이 인정되었으나, 다른 수종들에서는 통계적 유의성이 안정되지 않았다. 낙엽송, 구상나무 및 종비나무는 pH 4.0 처리구에서, 젓나무와 삼나무는 pH 5.0 처리구에서 각각 묘고가 가장 크게 나타났다. 3. 개체당 건중량에서 낙엽송과 젓나무에서는 고도의 통계적 유의성이 인정되었으나, 구상나무, 종비나무 및 삼나무에서는 통계적 유의성이 인정되지 않았다. 낙엽송과 구상나무는 pH 4.0 처리구에서, 젓나무와 삼나무는 pH 3.0 처리구에서, 종비나무는 대조구에서 각각 최대건중량을 보였다. 4. 처리산성우의 pH값이 작아질수로 피해가 나타난 침엽의 수 및 개체수가 증가하는 경향이 뚜렷하였다. 5. 토양산도는 모든 수종에서 처리간 고도의 통계적 유의성이 인정되었다.

  • PDF