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A Study on the Evolution of 3,4-DCA and TCAB in Some Selected Soils(Part II) -Degradation of $^{14}C-3,4-DCA\;and\;^{14}C-TCAB$- (수종토양중(數種土壤中)에서 3,4-DCA 및 TCAB의 변화(變化)에 관(關)한 연구(硏究)(제2보(劑二報)) -$^{14}C-3,4-DCA$$^{14}C-TCAB$ 의 분해(分解)-)

  • Lee, Jae-Koo;Fournier, J.C.
    • Applied Biological Chemistry
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    • v.21 no.2
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    • pp.71-80
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    • 1978
  • In an attempt to elucidate the fate of 3,4-DCA and TCAB in various French soils, uniformly $^{14}C-ring-labeled$ 3,4-DCA and TCAB mere utilized and the following results obtained. 1) The rate of breakdown of $^{14}C-3,4-DCA$ into $^{14}CO_2$ was relatively higher in the early stage than that in the later stage. In 6 months of incubation in alkaline soil (pH 7.9), the rate was as high as 6.5% at dose 1 (1.5 ppm) and as low as 1.92% at dose 2(94 ppm), whereas in organic acid soil (pH 5.5) the rate was 4.91% at dose 1 and 4.24% at dose 2, respectively, without making any great difference between the two levels. 2) At dose 1, 47.70% of the initial radioactivity of $^{14}C-3,4-DCA$ was bound to soil in organic acid soil and 29.49% bound in alkaline soil, whereas at dose 2, 38.40% in organic acid soil and 20.30% in alkaline soil, respectively. 3) The amount of formation of $^{14}C-TCAB$ from $^{14}C-3,4-DCA$ seems to depend largely on the concentration of 3,4-DCA applied rather than on soil types. At dose 2, the amount was 50% of the total radioactivity extracted in organic acid soil and 30% in alkaline soil, corresponding to 1.8% and 1.4% of the initial radioactivity applied to soil, respectively. Cis-TCAB also seemed to be formed at dose 2 in both soils. Meanwhile, at dose 1, even though $^{14}C-TCAB$ was detected in trace on tlc and glc in both soils, the amount does not exceed 2 to 3% of the radioactivity extracted, corresponding to 0.05 to 0.1% of the initial radioactivity. 4) The rate of breakdown of $^{14}C-TCAB$ into $^{14}CO_2$ ranged from 0.05 to 0.20% in all the four soils. Most of the applied $^{14}C-TCAB$ remained intact after 3 months, not producing any detectable metabolites. 5) The fact that much more $^{14}C-TCAB$ was adsorbed to alkaline soil than to the other soils strongly indicates that in alkaline condition trans-isomer was converted tocisisomer which has the higher adsorption affinity than the former.

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Sensitivity Experiment of Surface Reflectance to Error-inducing Variables Based on the GEMS Satellite Observations (GEMS 위성관측에 기반한 지면반사도 산출 시에 오차 유발 변수에 대한 민감도 실험)

  • Shin, Hee-Woo;Yoo, Jung-Moon
    • Journal of the Korean earth science society
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    • v.39 no.1
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    • pp.53-66
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    • 2018
  • The information of surface reflectance ($R_{sfc}$) is important for the heat balance and the environmental/climate monitoring. The $R_{sfc}$ sensitivity to error-induced variables for the Geostationary Environment Monitoring Spectrometer (GEMS) retrieval from geostationary-orbit satellite observations at 300-500 nm was investigated, utilizing polar-orbit satellite data of the MODerate resolution Imaging Spectroradiometer (MODIS) and Ozone Mapping Instrument (OMI), and the radiative transfer model (RTM) experiment. The variables in this study can be cloud, Rayleigh-scattering, aerosol, ozone and surface type. The cloud detection in high-resolution MODIS pixels ($1km{\times}1km$) was compared with that in GEMS-scale pixels ($8km{\times}7km$). The GEMS detection was consistent (~79%) with the MODIS result. However, the detection probability in partially-cloudy (${\leq}40%$) GEMS pixels decreased due to other effects (i.e., aerosol and surface type). The Rayleigh-scattering effect in RGB images was noticeable over ocean, based on the RTM calculation. The reflectance at top of atmosphere ($R_{toa}$) increased with aerosol amounts in case of $R_{sfc}$<0.2, but decreased in $R_{sfc}{\geq}0.2$. The $R_{sfc}$ errors due to the aerosol increased with wavelength in the UV, but were constant or slightly decreased in the visible. The ozone absorption was most sensitive at 328 nm in the UV region (328-354 nm). The $R_{sfc}$ error was +0.1 because of negative total ozone anomaly (-100 DU) under the condition of $R_{sfc}=0.15$. This study can be useful to estimate $R_{sfc}$ uncertainties in the GEMS retrieval.

New Synthesis of Sestamibi and Comparison of Stability of Its Formulation (Sestamibi의 신규합성과 제제화에 따른 안정성 비교)

  • Son, Mi-Won;Lim, Joong-In;Chang, Young-Soo;Jung, Mi-Young;Jeong, Lak-Shin;Kim, Soon-Hoe;Kim, Won-Bae;Jeong, Jae-Min
    • The Korean Journal of Nuclear Medicine
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    • v.35 no.5
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    • pp.334-341
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    • 2001
  • Purpose: Ascorbic acid us known to act as an antioxidant. Therefore, it can be used in increasing the efficiency of radiochemical labeling of Technetium-99m setamibi by inhibition of oxidation of $Sn^{2+}$ at low concentration. We intended to estimate the efficiency of radiochemical labeling and the stability of the newly formed formulation when ascorbic acid was added to a commercial kit. Materials and Methods: Synthesis of sestamibi was performed according to Dong-A's patent procedure (No.10-2001-0012877). First, we undertook a study to evaluate the efficiency of radiochemical labeling of sestamibi containing ascorbic acid. The stability of the vials was assessed using either $7.5{\mu}g\;or\;75{\mu}g$ of ascorbic acid, added to commercial vials under the accelerated condition(Temp : $40^{\circ}C{\pm}2^{\circ}C$, Relative humidity : $75{\pm}5%$). Results: Sestamibi was synthesized in overall 35-40% yield over 5 steps from a commercially available methallyl chloride as a starling material. When ascorbic acid was added, the efficiency of radiochemical labeling was maintained compared to the vial with no ascorbic acid. The accelerated test showed that the addition of ascorbic acid inhibited the oxidation of $Sn^{2+}$ ion by antioxidation mechanism. Also, the efficiency of radiochemical labeling of this vial after 9 months was nearly the same as the starting point. Therefore, the storage period of the kit is likely to be extended. Taken together, it suggests that the addition of ascorbic acid as a stabilizer is desirable. Conclusion: To increase the stability of a sestamibi cold kit, it is desirable to add ascorbic acid as a stabilizer to the commercial formulation.

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Comparisons of Regeneration Methods Using Physical and Chemical Treatment for Phosphate Removal Restoration of Filter Media (여재의 인 제거기능 회복을 위한 물리화학적 재사용 방안 비교)

  • Kim, Ji Ah;Choi, I Song;Oh, Jong Min;Kim, Won Jae;Park, Jae Roh
    • Ecology and Resilient Infrastructure
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    • v.3 no.3
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    • pp.201-206
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    • 2016
  • The purpose of this study is to find the regeneration method of filter media using physical and chemical treatment for restoration of phosphorus adsorption ability. The filtration material used in this study is called Adphos. In an experiment of heating treatment, re-used filter media is heated to a high temperature before the adsorption test. The results show that the $PO{_4}^{3-}-P$ adsorption capacity is in the range of 0.0021 - 0.0030 mg/g and the removal efficiency is in the range of 26.1 - 39.4%. In the experiment of acid or basic treatment, re-used filter media is exposed to a different pH condition before the adsorption test. The results show that the $PO_4^{3-}-P$ adsorption capacity is in the range of 0.0010 - 0.0066 mg/g and the removal efficiency is in the range of 15.8 - 87.1% after the acid treatments which have pH values of 1 - 5. However, after the basic treatments which have pH values of 8 - 11, the results show that the $PO{_4}^{3-}-P$ adsorption capacity is in the range of 0.0018 - 0.0034 mg/g and the removal efficiency is in the range of 26.7 - 48.0%. In an experiment of chemical treatment using NaCl, re-used filter media was exposed to a different NaCl concentration before the adsorption test. The results show that the $PO{_4}^{3-}-P$ adsorption capacity is in the range of 0.0036 - 0.0050 mg/g and the removal efficiency is in the range of 50.5 - 71.1%. In conclusion, chemical treatment using NaCl shows a high recovery probability of phosphorus adsorption ability of filter media.

Seasonal Variation and Natural Attenuation of Trace Elements in the Stream Water Affected by Mine Drainage from the Abandoned Indae Mine Areas (인대광산 지역 광산배수에 영향을 받은 하천에서 미량원소의 계절적인 수질변화와 자연저감)

  • Kang, Min-Ju;Lee, Pyeong-Koo;Choi, Sang-Hoon
    • Economic and Environmental Geology
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    • v.40 no.3 s.184
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    • pp.277-293
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    • 2007
  • Seasonal and spatial variations in the concentrations of trace elements, pH and Eh were found in a creek watershed affected by mine drainage and leachate from several waste rock dumps within the As-Pb-rich Indae mine site. Because of mining activity dating back to about 40 years ago and rupture of the waste rock dumps, this creek was heavily contaminated. Due to the influx of leachate and mine drainage, the water quality of upstream reach in this creek was characterized by largest seasonal and spatial variations in concentrations of Zn(up to $5.830 mg/{\ell}$), Cu(up to $1.333 mg/{\ell}$), Cd(up to $0.031 mg/{\ell}$) and $SO_4^{2-}$(up to $173 mg/{\ell}$), relatively acidic pH values (3.8-5.1) and highly oxidized condition. The most abundant metals in the leachate samples were in order of Zn($0.045-13.909 mg/{\ell}$), Fe($0.017-8.730mg/{\ell}$), Cu($0.010-4.154mg/{\ell}$) and Cd($n.d.-0.077mg/{\ell}$), with low pH(3.1-6.1), and high $SO_4^{2-}$(up to $310 mg/{\ell}$). The mine drainage also contained high concentrations of Zn, Cu, Cd and $SO_4^{2-}$ and remained constantly near-neutral pH values(6.5-7.0) in all the year. While the leachate and mine drainage might not affect short-term fluctuations in flow, it may significantly influence the concentrations of chemicals in the stream. The abundance and chemistry of Fe-(oxy)hydroxide within this creek indicated that the Fe-(oxy)hydroxide formation could be responsible for some removal of trace elements from the creek waters. Spatial and seasonal variations along down-stream reach of this creek were caused largely by the influx of water from uncontaminated tributaries. In addition, the trace metal concentrations in this creek have been decreased nearly down to the background level at a short distance from the discharge points without any artificial treatments after hydrologic mixing in a tributary. The nonconservative(i.e. precipitation, adsorption, oxidation, dissolution etc.) and conservative(hydrologic mixing) reactions constituted an efficient mechanism of natural attenuation which reduces considerably the transference of trace elements to rivers.

The Effects of Protozoa on the Early Formation of Microbial Fouling Communities of Inchon Coastal Waters (인천 연안 미세오손생물 군집 형성과 원생동물의 영향)

  • Choi, Joong-Ki;Yang, Eun-Jin;Lee, Won-Je;Yoon, Won-Duk;Shim, Jae-Hyung
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.4 no.4
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    • pp.349-362
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    • 1999
  • To understand the role of protozoa in the early formation of microbial fouling community, the studies on the formation of microbial film, the succession of microbial fouling communities, and the grazing pressure on bacteria population in microbial film were carried out in the laboratory, Inchon outer port and Inchon inner harbour. Bacteria and heterotrophic flagellates formed primary microbial film on the aluminum surface within 6 hours and oligotrich ciliates were observed 2 cells $mm^{-2}$ on the same surface at 9 hours in Inchon inner harbour which had physically stagnant condition. The larvaes of Balanus albicostatus which were dominant meiobenthos in Inchon coastal area attached on the glass surface at the first day of experiment. Heterotrophic flagellates showed maximum abundance of 465 cells $mm^{-2}$ at the 13rd day and ciliates showed maximum abundance of 63 cells $mm^{-2}$ at the 11st day in the Inchon inner harbour. In the Inchon outer port which opens to the outer sea, the maximum abundance of protozoa occurred at early phase, but not so many. The dominant heterotrophic flagellates were Metrornonas simplex and Bodonids. Dominant ciliates were small tintinnids and oligotrich ciliate Strombidium sp., Large Strombidium (oligotrich ciliate) and sessile Acineta turberosa (suctorian ciliate) occurred after 10 days. The attached larvae of Balanus occurred as biofouling organism on the early surface and showed maximum abundance of 18 indiv. $cm^{-2}$ at 7th day. At that time, adult barnacles were observed on the surface and dead barnacles were observed after two days. Except barnacles, the larvaes of Anthozoa sp., Oysters (Crassostrea gigas) and Polychaeta were observed on the surface from 3rd day. 3 benthic copepods including Harpacticus sp., I isopod, 1 polychaeta and 1 gastropoda were observed as predators of the microbial film on the surface after 7 days when microbial film developed very well. Although the ingestion rates of protozoa on the bactctia of the rnicrobi31 film were relatively low, the average grazing rate of protozoa on bacteria was high of 0.058 $h^{-1}$. This implied that the grazing pressure of protozoa influences the mortality of bacteria populations on the microbial film. but protozoa cannot get enough energy from only bacteria on the microbial film.

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Rhizosphere Enhances Removal of Organic Matter and Nitrogen from River Water in Floodplain Filtration (홍수터 여과를 이용한 하천수의 질소와 유기물 제거에 미치는 근권의 효과)

  • Jeong, Byeong-Ryong;Chung, Jong-Bae;Kim, Seung-Hyun;Lee, Young-Deuk;Cho, Hyun-Jong;Baek, Nam-Joo
    • Korean Journal of Soil Science and Fertilizer
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    • v.36 no.1
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    • pp.8-15
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    • 2003
  • If contaminated river water is sprayed over a floodplain, the microbial processes can simultaneously remove organic matter and nitrogen during the infiltration through the sediment profile. The effect of rhizosphere on the removal of organic matter and nitrogen from contaminated river water was investigated using floodplain lysimeters. River water was sprayed at a rate of $68.0L\;m^{-2}\;d^{-1}$ on the top of the lysimeters with or without weed vegetation on the surface, Concentrations of $NO_3$, $NH_4$ and dissolved oxygen (DO), and chemical oxygen demand (COD) and Eh in water were measured as functions of depth for 4 weeks after the system reached a steady state water flow and biological reactions. A significant reductive-condition for denitrification developed in the 30-cm surface profile of lysimeters with weeds. At a depth of 30 cm, COD and $NO_3$-N concentration decreased to 5.2 and $0.9mg\;L^{-1}$ from the respective influent concentrations of 18.2 and $9.8mg\;L^{-1}$. The removal of $NO_3$ in lysimeters with weeds was significantly higher than in those without weeds. Vegetation on the top was assumed to remove $NO_3$ directly by absorption and to create more favorable conditions for denitrification by supply of organic matter and rapid $O_2$ consumption, In the lysimeters without weeds, further removal of $NO_3$ was limited by the lack of an electron donor, i.e. organic matter. These results suggest that the filtration through native floodplains, which include rhizospheres of vegetation on the surface, can be effective for the treatment of contaminated river water.

Studies on the Denitrification in the Submerged Paddy Soil -IV. Influences of soil organic matter contents, soil temperature, pH values, kinds and levels of N-fertilizer on the evolution of N2O gas (논토양(土壤)의 탈질작용(脫窒作用)에 관(關)한 연구(硏究) -제(第)4보(報) 토양유기물함량(土壤有機物含量), 온도(溫度), pH, 질소비종(窒素肥種) 및 시비량(施肥量)이 탈질작용(脫窒作用)에 미치는 영향(影響))

  • Lee, Sang Kyu;Kim, Seung Hwan;Park, Jun Kyu;An, Sang Bae
    • Korean Journal of Soil Science and Fertilizer
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    • v.20 no.1
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    • pp.55-61
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    • 1987
  • A series of laboratory experiments were carried out to find the effects of soil organic matter contents, soil temperature, pH values, kinds and amount of nitrogen fertilizers on the denitrification-$N_2O$ gas evolution-. The results obtained were summarized as follows: 1. Denitrification rate, amount of $N_2O$ gas evolution, was influenced the order of organic matter contents>soil temperature>pH values>kinds of N-fertilizer>levels of N-fertilizer. 2. The highest dentrification rate was observed in organic matter content of 3.0%, pH values at 6.0 with application of $KNO_3$ at levels of 20 mgN/100g soil. 3. For the evolution of I mole $N_2O$ gas, averaged carbon consumption was obtained as 0.5 mole in all these experiment condition. However, the highest carbon consumption rate was obtained in organic matter contents for 1.0% with application of $(NH_4)_2SO_4$ at levels of 10 mgN/100g soil (1.06 mole) while lowest carbon consumption rate was obtained in organic matter contents for 3.0% with application of $KNO_3$ at levels of 20 mgN/100g soil (0.13 mole). 4. According to Michaelis-Menten's equation, the V/2 values for evolution of $N_2O$ gas was estimated by progress curve. The results obtained was as 550 ug for $(NH_2)_2CO$ and 1100 ug $N_2O/100g$ soil by application of $KNO_3$ in organic matter contents of 1.0% soil. On the other hand, when the application $(NH_4)_2SO_4$ the V/2 values of $N_2O$ gas was obtained as the amount of 490 ug/100g soil while V/2 values of $N_2O$ gas by application of $KNO_3$ was on the linear line in soil organic matter contents of 3.0%.

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Phytotoxic Effect of Herbicides on Upland Crops and Weeds (밭작물(作物) 및 잡초(雜草)에 대한 제초제(除草劑)의 약해(藥害) 약효(藥效))

  • Ryang, H.S.;Chun, J.C.;Yim, J.H.
    • Korean Journal of Weed Science
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    • v.4 no.1
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    • pp.69-78
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    • 1984
  • This study was conducted to select herbicides effective for upland crops and to investigate the cause of crop injury in peanut cultivated with mulching. Crop such as radish (Raphanus acanthiformis Moor.), Chinese cabbage (Brassica raps L.), soybean (Glycine max Merr.), Peanut (Archis hypogaea L.), and marsh mallow (Malva olitoria Nakai) were tolerant to napropamide [2-(${\alpha}$-naphthoxy)-N, N-diethylpropionamide], alachlor [2-chloro-2', 6'-diethyl-N-(methoxymethyl) acetanilide], trifluralin (${\alpha},{\alpha},{\alpha}$-trifluoro-2, 6-dinitro-N, N-dipropylp-toluidine) and nitrofen (2,4-dichlorophenyl-p-nitrophenylether). Napropamide, diphenamide (N, N-dimethyl-2, 2-diphenylacetamide) and alachlor were safe for red pepper (Capsicum annuum L.), eggplant (Solanum melongena L. and tomato (Lycopersicon esculentum Mill.), while trifluralin, nitrofen and chlonitrofen (2,4,6-trichlorophenyl-4-nitrophenyl ether) could be used for water melon (Citrullus battich Forsk.), carrot (Daucus carota L.) and lettuce (Lactuca scariola L.) without crop injury. Out of nine major weed species studied, Capsella bursa-pastoris Medicus was the most resistant species to the herbicides tested. Napropamide and alachlor could not control P. hydropiper, while P. oleracea and C. album were tolerant to diphenamide :and alachlor, respectively. Urea herbicides such as methabenzthiazuron [3-(2-benzothiazolyl)-1,3-dimethylurea], linuron [3-(3, 4-dichlorophenyl~l-methoxy-i-methyl urea], and isoproturon [3-(4-isopropylphenyl) -1, 1-dimethylurea]gave a great injury to the crops studied. The weeding effect was greater for broadleaf weeds than for grasses. Isoproturon and linuron provided good selectivity for marsh mallow and carrot, respectively. In peanut, the crop injury caused by Four herbicides studied was greater when cultivated with mulching than when cultivated without mulching. With dinitroaniline herbicides the crop injury decreased as the gaseous herbicide was removed out of mulching. Alachlor gave little phytotoxicity to peanut grown under mulching condition and nitralin [4-(methylsuphonyl)-2, 6-dinitro-N, N-dipropylaniline] showed less toxicity to the peanut than pendimenthalin (3,4-dimethyl-2, 6-dinitro-N-1-ethyl propylaniline) and trifluralin.

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Surgical Evaluation of Squamous Cell Carcinoma of the Lung (편평상피세포 폐암의 외과적 고찰)

  • An, Byeong-Hui;Mun, Hyeong-Seon;Na, Guk-Ju;Kim, Sang-Hyeong
    • Journal of Chest Surgery
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    • v.30 no.2
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    • pp.179-186
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    • 1997
  • The frequency of primary lung cancer is increasing compared to other cancer. Complete surgical resection is the most effective method of treatment, but it is limited to only 25 to 30 percent of patients after initial clinical presentation. The survival rate is different by the subtypes of carcinoma, stages, and general condition of patients. The author investigated the survival rate of 87 patients with squamous cell carcinoma of the lung after surgery. Age ranged from 31 to 73 years, with Lean 57.1) $\pm$ 7.15 and 80.5% (70 cases) was initially diagnosed at sixth and seventh decades. Male to female ratio was 8.9'1. Initial complaints were cough with sputum in 78.1%, weight loss in 31.0%, chest pain and discomfort in 29.9%, and hemoptysis in 24.1%. The location of the tumor was right side in 44.8% and left slde in 55.2% ; LUL in 39.1%, RLL in 20.7%, LLL in'16. 1%, RUL in 14.9% and RML in 9.2%. Stage I was 19.5%, stage II 25.3%, stage olla 54.1% and stage lIIb 1.1%. Operative procedures were as follow : pneumonectomy in 52.9%, lobectomy in 47.1%, sleeve upper lobectomy in 4 cases. Single mediastinal Iymph node involvement was observed in 17 cases, and multi-level mediastinal Iymph node involvement in 23 cases. Lower paratracheal Iymph node and subcarinal Lymph node were more frequently involved in right side lung cancer, with 8 and 10 cases, respectively and subaortic Iymph node was most frequently involved in left side lung cancer with 9 cases. Operative complications were hoarseness, wound infection and chylothorax in 7, 5 and 4 cases, respectively. The operative mortality was 2.2% and the cause of death was pulmonary edema. Postoperative follow-up period ranged from 1 month to 99 months with a mean of 29.95 $\pm$ 17.21 months. Overall one-year survival rate was 75.1 % and five-year survival rate was 29.8%. One-year and five-year survival rates were 93.7% and 52.4% for stage 1, 92.2% and 30.5% for st ge ll, and 61.2% and 17.4% for stage llla, respectively. These findings correlate survival rate with tumor size, mediastinal Iymph node metastasis and surgical resectability, and long-term survival can be expected with small sized tumor, absent mediastinal Iymph node metastasis and complete surgical resection.

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