• Title/Summary/Keyword: 산화율

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A study on the Degradation and By-products Formation of NDMA by the Photolysis with UV: Setup of Reaction Models and Assessment of Decomposition Characteristics by the Statistical Design of Experiment (DOE) based on the Box-Behnken Technique (UV 공정을 이용한 N-Nitrosodimethylamine (NDMA) 광분해 및 부산물 생성에 관한 연구: 박스-벤켄법 실험계획법을 이용한 통계학적 분해특성평가 및 반응모델 수립)

  • Chang, Soon-Woong;Lee, Si-Jin;Cho, Il-Hyoung
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.1
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    • pp.33-46
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    • 2010
  • We investigated and estimated at the characteristics of decomposition and by-products of N-Nitrosodimethylamine (NDMA) using a design of experiment (DOE) based on the Box-Behken design in an UV process, and also the main factors (variables) with UV intensity($X_2$) (range: $1.5{\sim}4.5\;mW/cm^2$), NDMA concentration ($X_2$) (range: 100~300 uM) and pH ($X_2$) (rang: 3~9) which consisted of 3 levels in each factor and 4 responses ($Y_1$ (% of NDMA removal), $Y_2$ (dimethylamine (DMA) reformation (uM)), $Y_3$ (dimethylformamide (DMF) reformation (uM), $Y_4$ ($NO_2$-N reformation (uM)) were set up to estimate the prediction model and the optimization conditions. The results of prediction model and optimization point using the canonical analysis in order to obtain the optimal operation conditions were $Y_1$ [% of NDMA removal] = $117+21X_1-0.3X_2-17.2X_3+{2.43X_1}^2+{0.001X_2}^2+{3.2X_3}^2-0.08X_1X_2-1.6X_1X_3-0.05X_2X_3$ ($R^2$= 96%, Adjusted $R^2$ = 88%) and 99.3% ($X_1:\;4.5\;mW/cm^2$, $X_2:\;190\;uM$, $X_3:\;3.2$), $Y_2$ [DMA conc] = $-101+18.5X_1+0.4X_2+21X_3-{3.3X_1}^2-{0.01X_2}^2-{1.5X_3}^2-0.01X_1X_2+0.07X_1X_3-0.01X_2X_3$ ($R^2$= 99.4%, 수정 $R^2$ = 95.7%) and 35.2 uM ($X_1$: 3 $mW/cm^2$, $X_2$: 220 uM, $X_3$: 6.3), $Y_3$ [DMF conc] = $-6.2+0.2X_1+0.02X_2+2X_3-0.26X_1^2-0.01X_2^2-0.2X_3^2-0.004X_1X_2+0.1X_1X_3-0.02X_2X_3$ ($R^2$= 98%, Adjusted $R^2$ = 94.4%) and 3.7 uM ($X_1:\;4.5\;$mW/cm^2$, $X_2:\;290\;uM$, $X_3:\;6.2$) and $Y_4$ [$NO_2$-N conc] = $-25+12.2X_1+0.15X_2+7.8X_3+{1.1X_1}^2+{0.001X_2}^2-{0.34X_3}^2+0.01X_1X_2+0.08X_1X_3-3.4X_2X_3$ ($R^2$= 98.5%, Adjusted $R^2$ = 95.7%) and 74.5 uM ($X_1:\;4.5\;mW/cm^2$, $X_2:\;220\;uM$, $X_3:\;3.1$). This study has demonstrated that the response surface methodology and the Box-Behnken statistical experiment design can provide statistically reliable results for decomposition and by-products of NDMA by the UV photolysis and also for determination of optimum conditions. Predictions obtained from the response functions were in good agreement with the experimental results indicating the reliability of the methodology used.

A Case Study on the Effective Liquid Manure Treatment System in Pig Farms (양돈농가의 돈분뇨 액비화 처리 우수사례 실태조사)

  • Kim, Soo-Ryang;Jeon, Sang-Joon;Hong, In-Gi;Kim, Dong-Kyun;Lee, Myung-Gyu
    • Journal of Animal Environmental Science
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    • v.18 no.2
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    • pp.99-110
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    • 2012
  • The purpose of the study is to collect basis data for to establish standard administrative processes of liquid fertilizer treatment. From this survey we could make out the key point of each step through a case of effective liquid manure treatment system in pig house. It is divided into six step; 1. piggery slurry management step, 2. Solid-liquid separation step, 3. liquid fertilizer treatment (aeration) step, 4. liquid fertilizer treatment (microorganism, recirculation and internal return) step, 5. liquid fertilizer treatment (completion) step, 6. land application step. From now on, standardization process of liquid manure treatment technologies need to be develop based on the six steps process.

Air Pollution and Its Effects on E.N.T. Field (대기오염과 이비인후과)

  • 박인용
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1972.03a
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    • pp.6-7
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    • 1972
  • The air pollutants can be classified into the irritant gas and the asphixation gas, and the irritant gas is closely related to the otorhinolaryngological diseases. The common irritant gases are nitrogen oxides, sulfur oxides, hydrogen carbon compounds, and the potent and irritating PAN (peroxy acyl nitrate) which is secondarily liberated from photosynthesis. Those gases adhers to the mucous membrane to result in ulceration and secondary infection due to their potent oxidizing power. 1. Sulfur dioxide gas Sulfur dioxide gas has the typical characteristics of the air pollutants. Because of its high solubility it gets easily absorbed in the respiratory tract, when the symptoms and signs by irritation become manifested initially and later the resistance in the respiratory tract brings central about pulmonary edema and respiratory paralysis of origin. Chronic exposure to the gas leads to rhinitis, pharyngitis, laryngitis, and olfactory or gustatory disturbances. 2. Carbon monoxide Toxicity of carbon monoxide is due to its deprivation of the oxygen carrying capacity of the hemoglobin. The degree of the carbon monoxide intoxication varies according to its concentration and the duration of inhalation. It starts with headache, vertigo, nausea, vomiting and tinnitus, which can progress to respiratory difficulty, muscular laxity, syncope, and coma leading to death. 3. Nitrogen dioxide Nitrogen dioxide causes respiratory disturbances by formation of methemoglobin. In acute poisoning, it can cause pulmonary congestion, pulmonary edema, bronchitis, and pneumonia due to its strong irritation on the eyes and the nose. In chronic poisoning, it causes chronic pulmonary fibrosis and pulmonary edema. 4. Ozone It has offending irritating odor, and causes dryness of na sopharyngolaryngeal mucosa, headache and depressed pulmonary function which may eventually lead to pulmonary congestion or edema. 5. Smog The most outstanding incident of the smog occurred in London from December 5 through 8, 1952, because of which the mortality of the respiratory diseases increased fourfold. The smog was thought to be due to the smoke produced by incomplete combustion and its byproduct the sulfur oxides, and the dust was thought to play the secondary role. In new sense, hazardous is the photochemical smog which is produced by combination of light energy and the hydrocarbons and oxidant in the air. The Yonsei University Institute for Environmental :pollution Research launched a project to determine the relationship between the pollution and the medical, ophthalmological and rhinopharyngological disorders. The students (469) of the "S" Technical School in the most heavily polluted area in Pusan (Uham Dong district) were compared with those (345) of "K" High School in the less polluted area. The investigated group had those with subjective symptoms twice as much as the control group, 22.6% (106) in investigated group and 11.3% (39) in the control group. Among those symptomatic students of the investigated group. There were 29 with respiratory symptoms (29%), 22 with eye symptoms (21%), 50 with stuffy nose and rhinorrhea (47%), and 5 with sore thorat (5%), which revealed that more than half the students (52%) had subjective symptoms of the rhinopharyngological aspects. Physical examination revealed that the investigated group had more number of students with signs than those of the control group by 10%, 180 (38.4%) versus 99 (28.8%). Among the preceding 180 students of the investigated group, there were 8 with eye diseases (44%), 1 with respiratory disease (0.6%), 97 with rhinitis (54%), and 74 with pharyngotonsillitis (41%) which means that 95% of them had rharygoical diseases. The preceding data revealed that the otolaryngological diseases are conspicuously outnumbered in the heavily polluted area, and that there must be very close relationship between the air pollution and the otolaryngological diseases, and the anti-pollution measure is urgently needed.

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Studies on the Browning of Red Ginseng (홍삼(紅蔘)의 갈변(褐變)에 관(關)한 연구(硏究))

  • Kim, Dong-Youn
    • Applied Biological Chemistry
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    • v.16 no.2
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    • pp.60-77
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    • 1973
  • The non-enzymatic browning phenomenons of red ginseng were studied to identify these compounds which function as the factors for browning. The samples were classified into five divisions; Fresh ginseng, blanched ginseng, sun dried red ginseng, dehydrated red ginseng, and browning accelerated red ginseng respectively, and the various compounds in each of them were analyzed quantitatively and investigated the compounds which were thought to function for browning during the drying and the dehydration processes; the results were as follows. 1. The chemical compositions among five divisions did not show any difference except a) total and reducing sugars, b) total acids, c) water soluble extracts; a) and b) were decreased during the drying process, c) was decreased about 6-7% in red ginseng divisions. 2. Sixteen free amino acids; asp., thr., ser., glu., gly., ala., val., cys., met., ileu., leu., tyr., phe., lys., his., and arg, were identified in each division. Among them the arg, was extremly high. All of the essential amino acids were contained, while generally these amino acids were decreased in drying period and their rates were smaller in dehydrated red ginseng than in sun dried red ginseng. 3. Three kinds of sugars; fructose, glucose and sucrose were identified and other four kinds of unidentified sugars were seperated. The content of sucrose was 80% and all kind of sugars were generally less in red ginseng divisions than in the other two divisions. The decreasing rate of sngars was higher in the sun dried red ginseng than in the dehydrated red ginseng. Especially the decreasing rate of the reducing sugars was high as compared with that of sucrose. 4. Almost all the ascorbic acid was decomposed during the blanching whereas there could'nt be shown any change of the ascorbic acid content during the period of drying. 5. Eleven kinds of volatile acids; acetic acid, propionic acid, acrylic acid, iso-butyric acid, n-butyric acid, isovaleric acid, n-valeric acid, isoheptylic acid, n-heptylic acid, and an unknown volatile acid were identified. They showed a little decrease during the period of blanching perhaps on account of their volatility whereas they were increased in drying period. 6. Six kinds of non-volatile acids; citric acid, malic acid, ${\alpha}-ketoglutaric$ acid, succinic acid, pyruvic acid and glutaric acid were identified. The content of them were decreased during the drying procedures in red ginseng but only that of succinic acid was increased. 7. Three kinds of polyphenols; 3-caffeyl quinic acid, 4-caffeyl quinic acid, 5-caffeyl quinic acid and an unknown polyphenol were identified. The content of them showed considerable decrease during the drying procedures, especially in sun drying. 8. The intensity of the browning in each divisior was as follows; browning accelerated red ginseng> sun dried red ginseng> dehydrated red ginseng. 9. In the process of red ginseng preparation, a. certain relationship could be found between the decreasing rates of amino acids, reducing sugars, polyphenols and the intensity of browning. Therefore the browning phenomenon may be concluded that nonenzymatic browning reactions of the amino-carbonyl reaction and autoxidation of polyphenols are the most important processes, furthermore, as their reactions could be controlled it is thought to be possible to accelerate effectively browning within a relatively short period.

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The Effect of SO2 and H2O on the NO Reduction of V2O5-WO3/TiO2/SiC Catalytic Filter (V2O5-WO3/TiO2/SiC 촉매필터의 NO 환원에 SO2와 H2O가 미치는 영향)

  • Ha, Ji-Won;Choi, Joo-Hong
    • Korean Chemical Engineering Research
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    • v.52 no.5
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    • pp.688-693
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    • 2014
  • For investigating NO reduction activity of an catalytic filter, the catalytic performance was measured under the presence of $SO_2$ and $H_2O$, respectively or simultaneously in the simulation gas composed of NO, $NH_3$, and air. The catalytic filter was prepared by coating $V_2O_5-WO_3/TiO_2$ catalyst on the pore surface of SiC filter element of which the superior performance for the particulate removal was well known. At the temperature below $260^{\circ}C$, the catalytic activities were enormously decreased under the presence of $SO_2$ and $H_2O$, respectively or simultaneously, compared with those under the cases of the absence of $SO_2$ and $H_2O$. However, the presence of $SO_2$ promoted the performance of the catalytic filter above $320^{\circ}C$ with showing the NO conversion better than 99.8% for the NO inlet concentration of 500 ppm and at the face velocity of 2 cm/s. In particular, the presence of water showed high NO conversion higher than 99% up to high temperature of $380^{\circ}C$. This effect of water was explained by the reason that it retarded the ammonia oxidation which is the main step into the formation of $N_2O$. The initial NO reduction activity of the catalytic filter maintained for the duration of 100 hours in the presence of $SO_2$ and $H_2O$. Therefore, it was concluded that the catalytic filter was promisingly useful for the industrial NOx reduction catalyst in order to treat the particulate and NO simultaneously.

A Study on the removal of nitrogen by combined nitrification and autotrophic denitrification (질산화와 무기영양 독립탈질화의 연계처리에 의한 질소제거에 관한 연구)

  • Han, Gee-Bong;Jeong, Da-Young;Woo, Mi-Hee;Kim, So-Yeon;Kim, Bio
    • Journal of the Korea Organic Resources Recycling Association
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    • v.16 no.2
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    • pp.74-80
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    • 2008
  • Removal of nitrogen compound under nitrification related with denitrification by biofilm which developed on the porous media was investigated. With the investigation of $NH_4-N$ nitrification and autotrophic denitrification supplied with sulfur media as electron donor, conclusions were retrieved as follows. When $F/M_N$ ratio of $NH_4-N$ was increased from $0.0062-0.034gNH_4-N/g\;MLVSS{\cdot}day$ by the change of influent concentration and HRT the nitrification rate decreased as the increase of loading rate. Also under the same conditions of $F/M_N$ ratio, the alkalinity consumption rate of operation was higher at 8 hours of HRT than at 6 hours of HRT. Accordingly the influent loading rate variation by detention time with influent flow influenced more on the nitrification efficiency than the influent loading rate variation by the influent concentration did. Denitrification rate with various EBCT(Empty Bed Contact Time) showed average 25% at 8.4hrs of EBCT but sharply decreased average 5% at 4.6hrs of EBCT, so the operation would be more effective at above 8.4hrs of EBCT. Also denitrification rate was known to be adversely increased as $NO_3-N$ loading rate per unit volume of sulfur-media was decreased within the range of $0.5{\sim}2.0kgNO_3-N/m^3{\cdot}day$.

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Antitumor and Free Radical-Scavenging Activities of Various Extract Fractions of Fruits and Leaves from Prunus mume (금매와 매화 잎 추출물의 프리라디칼 억제 활성 및 항암 효과)

  • Rho, Kyu-A;Kim, Gyeong-Ji;Ji, Hyun-A;Lim, Han-Sol;Chung, Kang-Hyun;Lee, Kwon-Jai;Song, Byeong Chun;An, Jeung Hee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.8
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    • pp.1137-1143
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    • 2015
  • This study investigated the free radical-scavenging and antitumor activities of hot water, water, acetone, ethanol, ethyl acetate, chloroform, and hexane extracts of fruits and leaves from Prunus mume. The various extracts were evaluated for their total polyphenol, flavonoid, and tannin contents, scavenging activities by DPPH and ABTS analyses, reducing power, protective effects against oxidative stress in L-132 cells, and antitumor activities against A549, HeLa, and U87 cancer cells. Ethanol extracts of fruits and leaves showed the highest total polyphenol content (336.41 and 523 mg GAE/100 g, respectively). DPPH and ABTS radical-scavenging activities increased according to concentration of fruit. DPPH radical-scavenging activity of ethanol extracts from leaves was 65.48% at $200{\mu}g/mL$. All extract fractions of leaves showed high ABTS radical-scavenging activities. The reducing power activities increased according to increasing concentration of fruits and leaves. All extracts of leaves performed better than extracts of fruits in terms of protective effects against oxidative stress in L-132 cells. Ethyl acetate, chloroform, hexane, ethanol extracts of fruits and leaves showed anticancer activities against A549, HeLa, and U87 cancer cells. However, ethanol extracts of fruits and leaves showed no toxicity in normal cells (BNLCL2). This study suggests that antioxidant activities of fruits and leaves from P. mume depend on polyphenol contents. Thus, fruits and leaves from P. mume can be useful as natural antioxidant compounds.

Antioxidant activities and Validation of Analytical Method of Marker compounds in strawberry fruits from various cultivars (딸기 품종별 추출물의 항산화활성 및 지표성분 밸리데이션)

  • Yong, Ye Seul;Lee, Songmi;Byun, Na-Young;Sun, Sangouk;Kim, Min-Jung;Jang, Seo Woo;Jang, Won Suk;Lee, Sun Yi;Yim, Soon-Ho
    • Korean Journal of Food Science and Technology
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    • v.51 no.6
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    • pp.517-523
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    • 2019
  • In this study, we investigated antioxidant capacity of 20 strawberry extract using the DPPH and ABTS assay and HPLC-DAD validation method. The total polyphenolic and flavonoids contents of 20 strawberry extracts were 22.77-107.61 mg TAE/100 g FW and 17.58-44.12 mg QE/100 g FW. The Aiberry and Elie star showed the highest total polyphenol and flavonoid contents, respectively. The DPPH radical scavenging activity of what was 1540.6-1124.0 μmol TEAC/100 g FW and Derunoka showed the highest activity. The ABTS radical scavenging activity was 6352.3-4592.3 μmol TEAC/100 g FW and FA23 showed the highest activity. The HPLC-DAD method for the quantitation of ellagic acid results showed high linearity in various concentration ranges, and the limit of detection was 2.35 μg/mL. The limit of quantification was 7.12 μg/mL. Relative standard deviation values from intra-and inter-day precision were less than 5.31%. Recovery rate at 10, 50, and 100 μg/mL, respectively, were 100.0-101.0% with relative standard deviation (RSD) values less than 5.30%. These results provide viable information for the validation of antioxidant capacity in strawberry fruits.

Effects of Green Tea on Weight Gain, Plasma and Liver Lipids and Lipid Peroxidation in Pair Fed Rats (Pair Fed 흰쥐에 있어서 녹차의 항증체, 지질개선 및 항산화 효과)

  • Kang, Jung-Ae;Chae, In-Sook;Song, Yong-Bo;Kang, Jung-Sook
    • Journal of Nutrition and Health
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    • v.41 no.7
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    • pp.602-611
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    • 2008
  • We compared antiobese, hypocholesterolemic, antiplatelet and antioxidant effect of 10% green tea powder and 3% green tea extract in rats pair fed 5% cholesterol diets. The final body weight was decreased significantly compared with the control (p < 0.05). Plasma and liver total cholesterol were lower in group of green tea powder or extract, but not statistically different. HDL cholesterol was increased significantly in group of green tea powder compared with the control or green tea extract (p < 0.05). Plasma triglyceride was significantly decreased in group of green tea extract compared with green tea powder, and green tea powder compared with the control respectively (p < 0.05). Liver triglyceride was significantly decreased in group of green tea powder or green tea extract compared with the control (p < 0.01). Platelet aggregations in the maximum and initial slope were not different among groups. Hemolysis was significantly lower in group of green tea powder compared with the control (p < 0.05). Plasma TBARS production was decreased in group of green tea extract compared with the control (p < 0.05). Na passive leak in intact cells was not different, but Na leak in AAPH treated cell was significantly decreased in group of green tea powder than the control (p < 0.05). The leak increase (${\Delta}Na$ Leak) after AAPH treatment was significantly decreased in groups of green tea powder and extract compared with the control (p < 0.05). Isotope excretion after $^{14}C$-cholesterol ingestion was significantly increased in group of green tea extract compared with the control or the green tea powder (p < 0.05). Consumption of green tea in powder or extract may give beneficial effects in weight control and plasma lipid profiles, impeding metabolic syndrome. More studies are needed to clarify what component of green tea and what mechanism are involved in antiobese and hypolipedemic actions of green tea.

Decomposition of 2,4,6-Trinitrotoluene (TNT) by Gamma Ray Irradiation (감마선 조사에 의한 2,4,6-Trinitrotoluene (TNT)의 분해)

  • Lee, Byung-Jin;Lee, Myun-Joo
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.1
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    • pp.1-10
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    • 2005
  • The purpose of this study was to evaluate the potential of a gamma irradiation to decompose 2,4,6-trinitrotoluene(TNT) in an aqueous solution. The decomposition reaction of TNT by gamma irradiation was a pseudo first-order kinetic over the applied initial concentrations($25{\sim}100mg/L$). The dose constant was strongly dependent on the initial TNT concentration. The removal of TNT was more efficient at pH below 3 and at pH above 11 than at neutral pH(pH 5-9). The required irradiation dose to remove over 99% of TNT was 40, 80 and 10 kGy, individually at pH 2, 7 and 13. The dose constant was increased by 1.6 fold and over 15.6 fold at pH 2 and 13, respectively, when compared with that at pH 7 When irradiation dose of 200 kGy was applied, the removal efficiencies of TOC were 91, 46 and 53% at pH 2, 7 and 13, respectively. Ammonia and nitrate were detected as the main nitrogen byproducts of TNT and glyoxalic acid and oxalic acid were detected as organic byproducts. The results showed that a gamma irradiation was an attractive method for the decomposition of TNT in an aqueous solution. However, regarding the application of high energy radiation for the TNT decomposition and mineralization, an application of an acidic pH below 3 to the solution before irradiation should be considered.