• Title/Summary/Keyword: 수리& #40;數理& #41;

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Quality Characteristics and Shelf Life of Noodles Prepared with Heracleum moellendorffii(Hogweed) Powder (어수리분말 첨가 국수의 품질특성 및 저장성)

  • Nam, Yoo-Hwa;Hong, Joo-Heon;Youn, Kwang-Sup;No, Hong-Kyoon;Lee, Shin-Ho
    • Food Science and Preservation
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    • v.17 no.5
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    • pp.602-607
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    • 2010
  • The quality characteristics and shelf life of wet noodles containing a freeze-dried powder of Heracleum moellendorffii(HM) were studied to investigate the use of HM as a food ingredient. The weight, volume, and water absorption of wet noodle sprepared with HM(HML) decreased as the concentration of HM increased. The turbidity of HML sauce and the loss in the solid content of noodles after cooking were lower than those of control noodles. Whiteness(L) and redness(a) values of wet noodles decreased but yellowness(b) increased after addition of HM. The sensory qualities of HML, including appearance, taste, color, flavor, texture, and overall acceptability, were better than those of control noodles. Addition of HM to 0.6%(w/w) afforded the best sensory qualities with respect to taste, texture, and overall acceptability. The total polyphenol content of HML increased as HM concentration increased. Noodle DPPH free-radical-scavenging activities were 22%(control), 28.41%(0.3%HM addition), 40.22%(0.6%HM addition) and 49.42%(0.9%HM addition). Viable bacterial cell counts did not differ significantly between control noodles and those prepared using 0.6%(w/w)HM during storage for 6day sat $10^{\circ}C$. However, viable cell numbers in noodles prepared using 0.9%(w/w) HM were significantly lower than those of control samples and of noodles prepared using either 0.3%(w/w) or 0.6%(w/w) HM, during storage for 12 days at $10^{\circ}C$. Changes in pH values showed trends similar to those of viable cell numbers during storage.

Anti-oxidative Activity and Chemical Composition of Various Heracleum moellendorffii Hance Extracts (추출 조건에 따른 어수리의 항산화 활성 및 성분 분석)

  • Bang, Ji-Eun;Choi, Hae-Yeon;Kim, Sun-Im
    • Food Science and Preservation
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    • v.16 no.5
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    • pp.765-771
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    • 2009
  • Anti-oxidative activities of Heracleum moellendorffii Hance extracts were measured after extraction with 50% (v/v) ethanol or water (at $80^{\circ}C$ or $20^{\circ}C$). The total polyphenol content was highest (64.73 mg GAE/g) in extract from 50% ethanol extraction at $80^{\circ}C$. In extracts obtained by water extraction at $80^{\circ}C$ and $20^{\circ}C$, the total polyphenol contents were 39.78 mg GAE/g and 23.17 mg GAE/g, respectively. The antioxidant activities of the ethanol extract at $80^{\circ}C$ were highest, as assessed by DPPH radical scavenging activity (69.14% at 50 ppm), reducing power (OD 0.93), and $ABTS^+$ radical-scavenging activity (85.62% at 1,000 ppm). At $80^{\circ}C$, the antioxidant activity of the 50% (v/v) ethanol extract was 8-20% higher than that of the water extract. Also, the chemical composition of extract from ethanol extraction at $80^{\circ}C$ was analyzed. The levels of moisture, crude protein, crude fat, and crude ash were 6.38%, 4.35%, 0.67%, and 1.96%, (all w/w), respectively. The Na, K, Mg, Zn, Fe, Ca, and P contents of the extract were 53.41, 398.26, 5.80, 0.40, 5.27, 3.56, and 47.17 mg/100 g, respectively. The total levels of polyphenolic compounds and flavonoids in the ethanol extract were 64.73 mg GAE/g and 49.54 mg RE/g.

Experiments for Amour Stability of Low Crested Structure Covered by Rocks (저 마루높이 구조물의 피복재 안정성 실험: 피복석 피복 조건)

  • Lee, Jong-In;Bae, Il Rho;Moon, Gang Il
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.40 no.1
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    • pp.35-41
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    • 2020
  • In this study, the stability of low crested structure armoured by rock has been investigated using two-dimensional hydraulic model tests. The effect of wave steepness and freeboard on the rock stability on crest, front, and the rear slope has been investigated. Rocks were mostly damaged near the upper part of the seaward slope and the crest of the seaward side. From the experimental data, the new empirical formula for the stability coefficients of the rocks was proposed.

Treatment of Artificial Sewage Using a Zeolite Column (제올라이트 칼럼에 의한 인공생활하수처리)

  • Seo, Jeoung-Yoon
    • Korean Journal of Environmental Agriculture
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    • v.21 no.3
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    • pp.178-188
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    • 2002
  • Constructed wetlands typically cost less to build and operate, and require less energy than standard mechanical treatment technology but they have similar performance to centralized wastewater treatment plants. Therefore, they were constructed especially many in rural areas, where are small villages but not industries. Plantless column tests were performed to investigate the possibility on using zeolite as a filter medium of constructed wetland for the wastewater treatment. Removal efficiency was $COD_{Cr}$ 94.63% T-P 41.41% and $NH_4^+-N$ 99.75% at hydraulic load 314 $L/m^2{\cdot}d$ and filtering height 100 cm filled with a zeolite mixture. This zeolite mixture consisted of 1 : 1 by volume of zeolites in the diameter range of 0.5 to 1 mm and 1 to 3 mm. Accordingly, hydraulic load 314 $L/m^2{\cdot}d$ was considered as optimal. Three zeolite mixtures were used to determine the optimal mixing ratio by volume of a zeolite (A) in the diameter range of 0.5 to 1 mm to a zeolite (B) in the diameter range of 1 to 3 mm 1 : 3, 1 : 1 and only B in A to B by volume were tested at hydraulic load 314 $L/m^2{\cdot}d$ and filtering height 100 cm $COD_{Cr}$ removal efficiency was more than 89% at mixing ratios of 1 : 3 and 1 : 1 in A to B. That of T-P ranged 56.42 to 58.72% and, that of T-N and $NH_4^+-N$ was 87% and 99% regardless of mixing ratios of two zeolites. Removal efficiency was lower at the column filled with only B. Removal efficiency was better at Inter medium filled with mixing ratio 1 : 1 in A to B than with the other mixing ratios. Thus, it was found that the mixture of mixing ratio 1 : 1 in A to B was appropriate far Inter medium of constructed wetland Removal efficiency was higher in down-flow than in up-flow, and all contaminants were removed most in 20 cm filter height near feeding area.

Effects of Particle Sizes on Non-Darcy Flow in Homogeneous Macro-porous Media (대규모 균일공극 매질에서 비Darcy 흐름에 대한 입자 크기의 영향)

  • Park, Sang Deog;Raksmey, Na;Sokan, Khe
    • Proceedings of the Korea Water Resources Association Conference
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    • 2019.05a
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    • pp.238-238
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    • 2019
  • 산지계곡에는 큰 자갈이나 호박돌이 무더기로 퇴적되어 있어서 대규모 공극을 구성한다. 호우시 이 돌무더기 내부에 빠른 흐름이 형성되고 이에 따른 퇴적사면의 급격한 변동이 발생하기도 한다. 본 연구에서는 대공극 매질의 흐름은 산지계곡에 퇴적된 균일 직경을 가진 구형 입자로 구성된 대규모 공극 매질을 구성하고, 비 Darcy 흐름의 유속에 미치는 입경의 영향을 수리실험으로 조사하였다. 실험에 사용된 구형 입자는 크기가 15.5mm, 25mm, 36.5mm인 유리구슬이고, 조성된 매질의 공극율은 Table 1과 같으며, 실험에서 침투거리는 40cm로 하였다. 실험유량은 0.98~15.41 t/s이고 입자 Reynolds 수는 120~4,580의 범위였다. 동수경사가 증가하면 매질의 단면평균 유속이 비선형적으로 증가하였다. 입경이 작을수록 유속과 동수경사 사이의 비선형적 경향이 더 크다(Fig.1). 동일한 동수경사에서 매질의 입경이 클수록 유속이 빠르게 나타났다.

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Engineering Properties for Planting of Porous Concrete Block Containing Rice Straw Ash (볏짚재를 혼입한 다공성콘크리트 블록의 식생을 위한 공학적 특성)

  • Sung Chan-Yong;Kim Young-Ik
    • Journal of the Korea Concrete Institute
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    • v.16 no.3 s.81
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    • pp.311-318
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    • 2004
  • This study was performed to examine engineering properties for planting of porous concrete block containing rice straw ash. Tests for void ratio, compressive and flexural strength, pH by neutralization treatment time and curing method were peformed. As results, the void ratio tends to decrease with increasing rice straw ash content. But, the compressive and flexural strength tends to increase with Increasing rice straw ash content. When the neutralization was treated at the curing age 6 days, the greatest strength was showed. The pH of porous concrete without neutralization treatment in dry and water curing are shown in 10.32 ${\~}$ 10.55 and 9.41${\~}$9.59, respectively. The pH of porous concrete by neutralization treatment in dry and water curing were shown in 9.74${\~}$10.10 and 8.13${\~}$9.32, respectively. The porous concrete block size was 23 ${\times}$ 23 ${\times}$ 4 cm, and species of planting were Tall fescue, Lespedeza cyrtobotrya and Lespedeza cuneata. At the 6 months after seeding, germination ratio and grown-up length of Tall fescue, Lespedeza cyrtobotrya and Lespedeza cuneata were shown in 90, 60, $50\%$, and 40${\~}$50, 90${\~}$110, 65${\~}$75 cm, respectively. These porous concrete block containing rice straw ash could be used for planting.

Performance and Hydraulic Characteristics of Drip Emitters (점적 emitter 의 성능과 수리적 특성)

  • 이남호
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.41 no.3
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    • pp.33-40
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    • 1999
  • Variations in the discharge rates of drip emittes were examined to find the effects of operation pressure and the tube length and to evaluate performance of the emitters. Several point-source emitters were selected such as pressure compensated, anti-leak pressure compensated, turbulent flow regulated, flow regulated, ready-made dripper, and spaghetti. Combination of operation pressure and tube length were compared. The microirrigatioon system was operated at pressures of 0.5 , 1.0 , 1.5 and 2.0 bar. The discharge from emitters wer collected at every ten meters along the lateral tube and weighted. In order to evaluate the drip emitters performance coeffcient of discharge variation , statistical uniformity, and emission uniformity were calculated. No significant variation in discharge along drip tube resulted with all emitters. There is no trend of variatiiono of discharge rate from pressure compensated emitters with increase in operation pressures. But discharge rate from other types of emitters increased with increase in operation pressures. The nominal discharge of each emitter was secured at pressure of 1.0 bar, Evaluation using statiscal and emission uniformity coefficients indicated that most of the emitters excepts tubulent flow regulated emitter and ready-made dripper performed at excellent level.

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Characteristics of Naturally Occurring Radioactive Materials in Groundwater from Aquifers Composed of Different Geological Settings in Ganghwa Island (강화도의 지질별 지하수 중 자연방사성 물질의 특성)

  • Kim, Ikhyun;Kim, MoonSu;Hamm, Se-Yeong;Kim, Hyunkoo;Kim, Dongsoo;Jo, Seongjin;Lee, Heonmin;Hwang, Jongyeon;Jo, Hunje;Park, Sunhwa;Chung, Hyenmi
    • Economic and Environmental Geology
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    • v.51 no.1
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    • pp.27-38
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    • 2018
  • Groundwaters in different rock types (Mesozoic granite, Precambrian gneiss, and schist) of Ganghwa island, Incheon City were characterized by using naturally occurring radioactive materials (NORM) and hydrogeochemical constituents. For the study, groundwater samples from 69 wells had been collected over eight years. Statistical methods were applied to relate hydrogeochemical components and NORM in the groundwater samples. The groundwater samples belonged to $Ca(Na)-HCO_3$ types. The uranium concentrations in three groundwater samples exceeded 30 ug/L of United States Environmental Protection Agency (US EPA) maximum contaminant level (MCL). The radon concentrations in 28 groundwater samples exceeded 4,000 pCi/L (picocuries per Liter) of US EPA alternative maximum contaminant level (AMCL). Gross-alpha in all the groundwater samples did not exceed 15 pCi/L of US EPA MCL. The average concentrations of uranium and radon in groundwater were the highest in granite area, and then gneiss, schist areas in order. In schist area, the correlation coefficient (R) between radon and $HCO_3$ is -0.40 and R between uranium and $SO_4$ is 0.54. In gneiss area, the R between radon and uranium is 0.55 and the R between uranium and $SO_4$ is 0.41. According to factor analysis, each geological area shows different chemical characteristics. The statistical analysis of whole groundwater resulted in nearly no significant relationship among uranium, radon and chemical constituents. Subsequently, more detailed studies on hydrogeological, geochemical, and geological characteristics related to NORM are required to better understand the behavior and fate of NORM.