• Title/Summary/Keyword: pH 시험

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Quality Characteristics of Unshiu Orange and Pear Packaged with Paper Incorporated with Antimicrobial Agents (항균소재를 함유한 포장재로 포장한 밀감과 배의 저장중 품질 특성 변화)

  • Park, Woo-Po;Jung, Jun-Ho;Cho, Sung-Hwan;Kim, Chul-Hwan
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.10
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    • pp.1715-1719
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    • 2004
  • In order to help the preservation of the unshiu orange and pear, antimicrobial paper incorporating grapefruit seed extract and zeolite was applied to pack fruits. Unshiu orange was packed in a box (24${\times}$24${\times}$22 cm) attached with antimicrobial paper and then stored respectively at l$0^{\circ}C$. Pears were wrapped individually before storage at l$0^{\circ}C$. During the storage, weight loss, pH, total acidity, soluble solid content, microbial load and decay were measured as quality indices. Steady pH increase in unshiu orange was observed to slightly decrease total acidity during the storage with little difference between the packaging treatments. The microbial loads of total aerobic bacteria, and yeast/mold counts were suppressed during storage by the antimicrobial paper packaging, which also contributed to reducing the decayed unshiu orange. Limited reduction of total aerobic bacteria and yeast/mold counts was observed only for initial storage period for the pears wrapped with 9 and 12% antimicrobial agent-added papers. Antimicrobial paper was useful for the reduction of microbial load in unshiu orange and pear without other quality deterioration.

Effects of Added Vegetable Oils on In vitro Formation of Fatty Acid Soaps and Fermentation Characteristics and NDF Disappearance Rate (식물성유 첨가가 In vitro 발효성상, NDF 소실율 및 지방산염 형성에 미치는 영향)

  • Kim, D.I.;Choi, J.R.;Lee, Y.H.;Lee, J.K.;Chung, T.Y.
    • Journal of Animal Science and Technology
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    • v.46 no.3
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    • pp.355-372
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    • 2004
  • In vitro experiments were conducted to determine the formation of fatty acid soaps (FAS) and neutral detergent fiber (NDF) disappearance rate. The substrates were a basal alfalfa hay containing 1) no oil, 2) 10% soybean oil, 3) 10% com oil, on a weight basis. All the substrates were incubated in triplicate for 0, 3, 6, 12, 24 and 48h in each experiment. After the incubation in the first experiment serum bottles (6oml) were analyzed for nonesterified, esterifed and fatty acid soaps contents. The serum bottles (120mI) from the second experiment were analyzed for pH, $NH_3-N$ and VFA concentration, and dry matter and NDF disappearance rate. pH decreased and the concentration of NH3-N increased significantly with longer incubation time (P<0.0001). The disappearance rates of dry matter and NDF significantly varied with feed, incubation time and oils (P<0.05). The molar concentration of total VFA increased and proportion of acetate significantly decreased with incubation time (P<0.0001), but the proportion of propionate significantly increased with longer incubation time (P<0.0001). Addition of oils to diet lowered the ratio of acetate:propionate (P<0.05). The esterified fatty acids (EFA) decreased with increasing incubation time (P<0.0001), and nonesterified fatty acids (NEFA) increased due to lipolysis of EFA, NEFA then reacted with cations to increase formation of FAS. The formation of FAS increased significantly at 48h of incubation time (P<0.0001). Especially, formation of stearic acid soaps was 27.5 and 32.5 folds with soybean oil and com oil supplements, respectively, by 48h of incubation time (P<0.0001). Alfalfa hay had higher cation contents, particularly Ca, which react with NEFA and FAS can be formed with longer incubation time. Saturated fatty acids had a higher proportion of FAS than did unsaturated fatty acids, suggesting that the former may react more extensively with cations. FAS contents increased with increasing chain length of the fatty acids. Since added vegetable oils fonned FAS, it might decrease negative effects on in vitro fermentation characteristics and NDF disappearance rate.

Recovery of N and P Resources from Animal Wastewater by Struvite Crystallization (Struvite 결정화에 의한 축산폐수로 부터 질소.인 자원의 재생)

  • Jo, W.S.;Yoon, S.J.;Ra, C.S.
    • Journal of Animal Science and Technology
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    • v.45 no.5
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    • pp.875-884
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    • 2003
  • Operational parameters for struvite crystallization, as a process to recover nitrogen and phosphorus resources from animal wastewater, were studied in this research. Crystallization distinctive of NH$_4$-N and PO$_4$$^{3-}$ in accordance to chemical sources, influent pH, aeration and stirring was examined using 2L of working volume of struvite reactor. Also, to find an effective treatment process combining with electrolysis method, removal characteristics of NH$_4$-N and PO$_4$$^{3-}$ in 6 different processes was tested. As chemical sources for the derivation of struvite formation, MgSO$_4$ and MgCl$_2$ were superior to CaCO$_3$ and CaCl$_2$. From experiment which was conducted to know the effects of aeration and stirring on struvite formation, it was revealed that aeration stimulated the crystallization reaction by inducing faster pH increase. While 90% of P removal was achieved within 1 hour under aeration, 14 hours was consumed under stirring condition. Struvite formation under aeration was affected by influent pH. No crystallization was observed at pH 5 level, but active crystallization reaction was induced over pH 6.0. 95% of P removal by struvite formation at pH 6, 7 and 9 was achieved within 3h, 2h and 10 min., respectively. However, over pH 10, operational problem due to excessive foam formation occurred, and blunting of crystallization reaction was observed at pH 11. When consider the pH range of animal wastewater, pH 7 to 9, efficient struvite formation could be achieved by simple aeration, without any chemical usage for pH adjustment. Among tested processes, the treatment process which electrolyzing the supernatant from struvite reactor, providing air to both reactors, showed best pollutant removal efficiencies. In this combined process, the removal efficiencies of NH$_4$-N and PO$_4$$^{3-}$ was 86% and 98%, respectively, and 92.4% of color removal was obtained.

Quality Control Tests and Acceptance Criteria of Diagnostic Radiopharmaceuticals (진단용 방사성의약품의 품질관리시험 및 기준)

  • Park, Jun Young
    • Korean Journal of Clinical Laboratory Science
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    • v.53 no.1
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    • pp.1-10
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    • 2021
  • Radiopharmaceuticals are drugs that contain radioisotopes and are used in the diagnosis, treatment, or investigation of diseases. Radiopharmaceuticals must be manufactured in compliance with good manufacturing practice regulations and subjected to quality control before they are administered to patients to ensure the safety of the drug. Radiopharmaceuticals for administration to humans need to be sterile and pyrogen-free. Hence, sterility tests and membrane filter integrity tests are carried out to confirm the asepticity of the finished drug product, and a bacterial endotoxin test conducted to assess contamination, if any, by pyrogens. The physical appearance and the absence of foreign insoluble substances should be confirmed by a visual inspection. The chemical purity, residual solvents, and pH should be evaluated because residual by-products and impurities in the finished product can be harmful to patients. The half-life, radiochemical purity, radionuclidic purity, and strength need to be assessed by analyzing the radiation emitted from radiopharmaceuticals to verify that the radioisotope contents are properly labeled on pharmaceuticals. Radiopharmaceuticals always carry the risk of radiation exposure. Therefore, the time taken for quality control tests should be minimized and care should be taken to prevent radiation exposure during handling. This review discusses the quality control procedures and acceptance criteria for a diagnostic radiopharmaceutical.

Response of Weed Population to Long-term Fertilizer Application (장기간 시비조건에 (施肥條件) 따른 잡초발생(雜草發生) 변화(變化)에 관한 (硏究))

  • Ku, Y.C.;Oh, Y.J.;Lee, J.H.
    • Korean Journal of Weed Science
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    • v.3 no.1
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    • pp.50-56
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    • 1983
  • A study was conducted to evaluate the weed population as affected by repeated application of fertilizers for 15 years (nonfertilized, PK, NK, NPK, NPK+Compost, NPK+Straw and NPK+lime). Alopecurus aequalis authority did not grow at all without P application and lime reduced the population of A. aequalis. Total number of weeds were the largest at 5-10cm soil layer and increased by application of compost and straw. Monochoria vaginalis dominated in NPK+compost and NP plot. Scirpus hotarui dominated in NPK+straw. Both Eleocharis kuroguwai and Potamogeton distinctus dominated in nonfertilized plot. Numbers of M. vaginalis and S. hotarui were larger low pH 6 while that of E. kuroguwai and P. distinctus at pH 6 to pH 7. Incidence of M. vaginalis and S. hotorui was great at pH's lower than 6, while E. kuroguwai and P. distinctus favored pH's ranging from 6 to 7.

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Evaluation on Field Application of Controlled Low-Strength Materials Made of Coal Ash in Reclamation Site (석탄회를 활용한 저강도고유동화재의 공유수면매립현장에 대한 적용성 평가)

  • Kong, Jin-Young;Jung, Hyuk-Sang;Cho, Sam-Deok;Kim, Ju-Hyong;Hyun, Jae-Hyuk;Chun, Byung-Sik
    • Journal of the Korean Geotechnical Society
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    • v.28 no.12
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    • pp.27-39
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    • 2012
  • This paper presented the strength and environmental characteristics of reclaimed-ground filled with controlled low-strength materials (CLSM) made of coal ash, small amounts of cement, and water in a reclamation site and evaluated the possibility of the use of coal ash on reclamation materials for beneficial use. Three-month period of SPT, CPT, environmental effects evaluation etc. were conducted. N values and cone resistances in ground filled with CLSM were greater than or similar to those in dredging sand. In case of land filled with coal ash except cement these values were lower than those in dredging sand. The results of soil and seawater pollution were lower than test criteria without high pH. Also the values of PH test were measured between pH 5.0~9.0, the criteria of industrial water in the Law for the Underground Water of Korea.

In-situ Stabilization of Heavy Metal Contaminated Farmland Soils Near Abandoned Mine, using Various Stabilizing Agents: Column Test Study (폐광산 주변 중금속 오염 농경지 토양복원을 위한 다양한 첨가제의 안정화 효율 비교: 컬럼시험연구)

  • Lee, Sang-Hoon;Cho, Jung-Hoon
    • Journal of Soil and Groundwater Environment
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    • v.14 no.4
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    • pp.45-53
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    • 2009
  • This study concerned remediation of heavy metal contaminated farmland soils near abandoned mine, using stabilization method, with particular emphasis on the remediating the soils contaminated with multi-elements. In this study, stabilizing heavy metals based on 'In-situ chemical fixation' has been applied to the soil collected from an abandoned mine in Korea, using column test, with various stabilizing agents, including $FeSO_4$, $KMnO_4$, sludge (collected from coal mine drainage treatment pond), zero-valent iron (ZVI), zeolite and $CaCO_3$. Sixty five-days operation of the flow-through columns yield $FeSO_4\;+\;KMnO_4$ and zeolite are efficient on reducing As leaching from the soil. ZVI and sludge are reducing the leaching of Cu. Although $FeSO_4\;+\;KMnO_4$ seem to be efficient for most heavy metals, high pH in the initial stage of test enabled high leaching of the heavy metals, whereas fixation of the heavy metals maintain throughout the rest of the test period, with increasing pH up to around 6. Addition of some alkaline agent may inhibit the low pH during the application. The column test was also run as two set: one set incubated with deionized water for 72 hours prior to starting the test, and the other without incubation. The incubated set demonstrated better stabilizing efficiency, indicating the potential optimized operation method.

Effects of Feeding Heat Treated Protein and Mineral Complex on In Vitro Fermentation Characteristics, Milk Production and Composition of Holstein Dairy Cows (열처리 단백질-광물질 복합제제 첨가가 In Vitro 발효성상과 착유우의 유량 및 유성분에 미치는 영향)

  • Choi, N.J.;Bae, G.S.;Nam, K.P.;Chang, M.B.;Um, J.S.;Ko, J.Y.;Ha, J.K.
    • Journal of Animal Science and Technology
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    • v.44 no.5
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    • pp.541-548
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    • 2002
  • This study, consisting of two experiments, was conducted to determine the effects of feeding heat treated protein and mineral complex (HPM) on milk production and composition, and ruminal fermentation of Holstein dairy cows. In in vitro experiment, HPM levels were 0, 0.2, 1 and 2%, and Timothy hay, which was substrate, was milled as 1 mm size, and the effects of HPM on pH, ammonia and VFA were analyzed after incubation times of 0, 6, 12, 24 and 48 h, respectively. The pH and ammonia production were not significantly different between treatments during the incubation. In addition, generally, total VFA and individual VFA were not affected by HPM on 0, 6 and 24 h. While, total VFA and individual VFA were increased in 0.2% and 1% of HPM supplemented treatments, but decreased in 2% of HPM treatment compared with control on 12 h. On 48 h, total VFA and individual VFA were increased in HPM treatments compared to control (P<0.05). However, A/P ratio was not affected by HPM supplementation. Gas production was higher in HPM treatment compared to control on 24 h (P<0.05) and 48 h (P<0.05). In lactating experiment, fourteen lactating Holstein cows were used for 4 months in a cross over experimental design. There were two treatments; no added HPM as a control and 0.2% of HPM added as a test treatment. Daily milk yield (P<0.001), 4% FCM (P<0.001), milk protein (P<0.05) and SNF (solid not fat; P<0.05) were increased in HPM treatment compared to control. While, milk fat, MUN (milk urea nitrogen) and SCC (somatic cell count) were not significantly different between treatments.

Changes in Kimchi Quality as Affected by the Addition of Boiled-Dried Fusiforme (녹미채 첨가가 김치의 숙성중 품질에 미치는 영향)

  • 박우포;조용범;이승철;김정목;이미정
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.5
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    • pp.834-838
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    • 2001
  • To investigate the effect of boiled-dried fusiforme for making kimchi, it was added as 0.1, 0.3 and 0.5% to brined Chinese cabbage by weight, respectively. Quality characteristics such as pH, titratable acidity, reducing sugar content, microbial loads were measured. Titratable acidity of 0.1% treatment showed a retarded increase compared to other samples, and maintained a higher reducing sugar content. Lactic acid bacteria numbers of boiled-dried fusiforme added kimchi were lower approximately by 2 log$_{10}$ CFU/mL after 10 day, which value was almost same as the control group. A 0.1% treatment of boiled-dried fusiforme showed no significant differences compared to the control in sensory evaluation.

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Hydrothermal Synthesis of Smectite from Zeolite (제올라이트로부터 스멕타이트 수열 합성에 대한 연구)

  • Chae, Soo-Chun;Kim, You-Dong;Jang, Young-Nam;Bae, In-Kook;Ryu, Kyung-Won;Lee, Sung-Ki
    • Journal of the Mineralogical Society of Korea
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    • v.19 no.4 s.50
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    • pp.301-310
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    • 2006
  • Smectites were synthesized from Na-P type and Na-A type zeolites by the hydrothermal synthetic method, and their physicochemical properties were studied. The optimal synthetic conditions for producing smectite were $290^{\circ}C$, 72 hr and $75{\sim}100kgf/cm^2$ in autogenous pressure. pHs of initial reaction solutions for the synthesis of smectites from Na-P type and Na-A type zeolite s were pH 6 and pH 10, respectively. The synthetic smectite was confirmed as $12{\AA}$-beidellite by a series of analysis such as X-ray diffraction analysis with random and oriented mounts, ethylene glycol treatment, and Greene-Kelly test, and their several physicochemical properties were studied.