• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.4
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• pp.41-49
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• 2023

This study examined the effect of input substrate concentration on hydrogen production of microbial electrolysis cells. To compare the performance of MEC according to the input substrate concentration, six laboratory-scale MEC reactors were operated by sequentially increasing the input substrate concentration from 2 g/L of sodium acetate, to 4 g/L, and 6 g/L. The current density, hydrogen production, and SCOD removal rate were analyzed, and energy efficiency and cathodic hydrogen recovery were calculated to compare the performance of MEC. The maximum volumetric current density was obtained at 4 g/L condition (76.3 A/m³) and it decreased to 19.0 A/m³, when the input concentration was increased to 6 g/L, which was a 75% decrease compared to the 4 g/L input condition. Maximum hydrogen production was obtained also at 4 g/L condition (47.3 ± 16.8 mL), but maximum hydrogen yield was obtained at 2 g/L input condition (1.1 L H₂/g COD_in). Energy efficiencies were also highest in 2 g/L condition; the lowest result was observed at 6 g/L condition. Maximum electrical energy efficiency was 76.4%, and the maximum overall energy efficiency was 39.7% at 2 g/L condition. However, when the substrate concentration increased to 6 g/L, the performance was drastically decreased. Cathodic hydrogen recovery also showed a similar tendency with energy efficiency, with the lowest concentration condition showing the best performance. It can be concluded that operating at low input substrate concentration might be better when considering not only hydrogen yield but also energy efficiency.

• Asian-Australasian Journal of Animal Sciences
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• v.3 no.3
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• pp.219-223
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• 1990

Sixtyfour Baluchi lambs about 5 months of age were divided into four groups with 16 lambs each. All the animals were grazed together. Group No.1 (G-1) was kept as control i.e. on grazing only; while group No. 2 (G-2) was offered barley grain @ 200 g/head/day as supplement to grazing; Group No. 3 (G-3) was offered ad-lib urea-molasses block (UMB) with 6% cement and group No.4 (G-4) was fed ad-lib IMB having 8% cement. These UMB were fed as supplement to grazing. Experiment lasted for 105 days (July to October) in arid zone of Baluchistan. Daily per head consumption of block No.1 was found to be 92.71 g; while that of block No.2 was observed to be 90.77 g. Growth rate (g/head/day) was found to be 10, 50, 33 and 15 in G-1, G-2, G-3 and G-4 respectively. Expenditure/kg bodyweight gain was found to be rupees 12.00, 3.64 and 7.74 for G-2, G-3 and G-4 respectively.

• Korean Journal of Food Science and Technology
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• v.21 no.5
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• pp.619-623
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• 1989

The cultural condition of Pseudomonas mendocina for polysaccharide production was examined. The optimal medium contains following composition per liter of distilled water: Sucrose 23.75g, $(NH_4)_2SO_4$ 1.57g, Yeast extract 0.5g, $KH_2PO_4\;2.9g,\;MgSO_4.\;7H_2O\;1.0g,\;CaCO_3$ 2.5g. The optimum temperature and pH were $30^{\circ}C$ and 6.5. At the condition. Ps mendocina produced 5.98g/l of polysaccharide. The culture viscosity after 3 days was 191mPa.s at $70sec^{-1}$. The product yield $(Y_{p/s})$ and specific productivity $(Q_p)$ were 25.18% and 32.83mg/g-cell/h.

• Journal of Korean Society of Water and Wastewater
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• v.13 no.2
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• pp.34-40
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• 1999

Aerobic night-soil treatment effluent containing high concentration of ammonia nitrogen was treated to remove nitrogen using Bardenpho process with Methanol addition. The objective of this study was to investigate the feasibility of complete nitrogen removal at three different HRTs such as 6.25d, 5d, and 3.75d, respectively. At each HRT, the nitrogen removal efficiencies are 92%, 99% and 97% and the required amount of methanol are 3.05gMeOH/gN, 2.75gMeOH/gN, and 3.38gMeOH/gN, respectively. Specific nitrification rates are decreased proportional to HRT and are $0.022gNH_4^+-N/g\;MLVSS{\cdot}day$, $0.0332gNH_4^+-N/g\;MLVSS{\cdot}day$ and $0.051gNH_4^+-N/g\;MLVSS{\cdot}day$ and specific denitification rate are decreased proportional to HRT and are $0.0210g\;N/gMLVSS{\cdot}day$, $0.0330g\;N/gMLVSS{\cdot}day$ and $0.0525g\;N/gMLVSS{\cdot}day$, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.496-502
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• 2004

The development of sesame varieties which contain high contents of lignan compounds has been progressed in Korea. This study was carried out to get the basic information for the breeding of high quality sesame varieties and the development of health functional food sources using lignan compounds from sesame. The contents of sesamin and sesamolin were $4.08\pm1.74$ and $2.47\pm0.68mg/g$, respectively, from sesame cultivated in 2002 and those were $4.08\pm1.51$ and $2.48\pm0.69mg/g$, respectively, from sesame cultivated in 2003. The content of sesamine was high in the order of Danbaek (6.22 mg/g), Seongbun (5.94 mg/g), Namda (5.83 mg/g), and Naman (5.59 mg/g) producted in 2002 and Seongbun (6.27 mg/g), Dasak (5.53 mg/g), Danbaek (5.50 mg/g), chinbaek (5.45 mg/g), and Seodun (5.41 mg/g) producted in 2003. The content of sesmoline was high in the order of Hwangbaek (3.27 mg/g), Seongbun (3.26 mg/g), Annam (3.22 mg/g), Hanseom (3.17 mg/g), and Danbaek (3.16 mg/g) producted in 2002, and Seongbun (3.21 mg/g), Seodun (3.14 mg/g), Pungan (3.10 mg/g), Naman (3.09 mg/g), and Danbaek (3.04 mg/g) producted in 2003. The contents of sesamin and sesamolin of Yangbaek, which has used as a standard variety for sesame breeding, were relatively lower than in any other varieties. These resluts suggest that Yangbaek is not the proper variety as a standard variety for development of high quality sesame. In conclusion, proper good variety as a standard variety for sesame breeding must be determined after careful consideration on the major quality factors including crude oil and lignan compounds as well as agricultural characteristics to develop high quality sesame varieties containing high contents of lignan compounds.

• Food Science and Preservation
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• v.17 no.5
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• pp.586-594
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• 2010

We evaluated changes in the microbiological quality and safety of food items (vegetables, seaweed, and processed food) supplied to elementary school food services to evaluate the distribution/delivery system. Pretreated vegetables, seaweed, and processed food were delivered to schools in refrigerated (${\leq}10^{\circ}C$) vans that made several delivery stops before arriving at the schools. During the distribution stage, total plate and coliforms counts were: bellflower roots $7.6{\times}10^5-6.7{\times}10^6$ and $5.8{\times}10^4-5.2{\times}10^5$ CFU/g; blanched bracken $4.5{\times}10^3-2.1{\times}10^5$, $5.0{\times}10^3-1{\times}10^4$ CFU/g; onion $1.2{\times}10^4-1.4{\times}10^4$, $5.0{\times}10$ CFU/g; soybean sprouts $9.6{\times}10^4-6.3{\times}10^7$ and $1.1{\times}10^3-1.2{\times}10^7$ CFU/g; soybean curd < $10-9.7{\times}10^5$ and < $10-2.3{\times}10^5$ CFU/g; and starch jelly < $10-3.8{\times}10^3$ and <10 CFU/g. Bacillus cereus < $10-4.1{\times}10^2$ CFU/g, Escherichia coli $1.0{\times}10-2.0{\times}10$ CFU/g, and Staphylococcus aureus $1.3{\times}10^2-4.1{\times}10^2$ CFU/g were detected on peeled bellflower, whereas B. cereus < $10-4.1{\times}10^2$ CFU/g, Listeria monocytogenes $1.0{\times}10-4.5{\times}10^2$ CFU/g, and S. aureus $1.8{\times}10^2-4.5{\times}10^2$ CFU/g, were detected on soybean sprouts. Most food items were double-wrapped in vinyl and placed in corrugated cardboard boxes prior to delivery, but the boxes, when placed in vans, were not segregated from other food items being delivered to schools and other destinations.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.2
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• pp.154-159
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• 1993

Theoretical prediction of the equilibrium of temperature and relative humidity dependance involving $HNO_{3(g)}-NH_{3(g)}$ and $NH_4NH_{3(s, aq)}$ was compared with atmospheric measurement of particulate nitrate$(NO_3^-)$, Ammonia-Nitric Acid partial pressure product $([$NH_{3(g)}][HNO_{3(g)}]ppb^2$) by a triple filter pack sampler from Oct 1991 to July 1992. The measured $HNO_3NH_3$ concentration product K was greater than equilibrium constant $K_p$ calculated from thermodynamic data of $NH_4NO_{3(s, aq)}-HNO_{3(g)}-NH_{3(g)}$ during fall, winter and spring. But K was lower than $K_p$ in summer. K was greater than $K_p$ as the result of supersaturation by air pollution, particularly anthropogenic $NH_3$.The reason of $K < K_p$ was due to removal of particulate nitrate$(NO_3^-)$ by rainout and washout. $NH_4NO_3$ which consists mainly of particulate nitrate is formed by reaction between $HNO_3$ and $NH_3$. As a result of the removal of particulate nitrate$(NO_3^-)$ by rainout and washout, concentrations of $HNO_3$ and $NH_3$ are decreased by equilibrium transfer(Le Chatelier's Law) in atmosphere.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.861-866
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• 2012

Water is the most important resource for the potato cultivation, especially to get the maximum water use efficiency and yield of potato, Water has to be applied moderately based on the water requirement of the potato. Crop water requirement (WR) is a function of the Potential evapo-transpiration(PET) and Crop coefficient (Kc). PET can be estimated by the climate data measured at the weather station in the production region. Kc was measured by the NIAST (RDA) through Lysimeter experiments. In this study, the growth stage of potato was divided as four (G-1 : Apr. 1~Apr. 15, G-2 : Apr. 16~May. 10, G-3 : May. 11~May. 31, G4 : Jun. 1~Jun. 15). The average PET during potato growing season of the 45 areas was $2.95mm\;day^{-1}$. The most water requirement was the G-3 stage among the potato growth stage. The MWR (Mean water requirement) according to growth stage was 1.0~1.2 (average 1.1), 1.5~1.8 (average 1.6), 1.9~2.2 (average 2.0) and 1.7~2.1 (average 1.8) mm $day^{-1}$, in the G-1, G-2, G-3 and G-4 stage, respectively. The TWR (Total water requirement) according to growth stage was 18.0~22.1 (average 19.3), 50.6~66.6 (average 56.3), 63.5~88.2 (average 72.4) and 38.3~54.5 (average 44) mm, in the G-1, G-2, G-3 and G-4 stage, respectively.

• Food Science and Preservation
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• v.16 no.2
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• pp.276-285
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• 2009

This study evaluated the microbiological quality and safety of food items(seafood, meat, eggs, and frozen food) supplied to elementary school food services, during delivery, and analyzed the distribution/delivery system. To this end, 10 food items supplied by 13 factories in Daegu and Gyeongbuk were chosen for study. Beef and pork were delivered directly to schools in freezer vans. Seafood, chicken, and frozen food were delivered to schools by refrigerated vans(${\leq}10^{\circ}C$) that made other delivery stops before arriving at schools. After food was delivered to schools, total bacterial counts and coliforms(respectively) were as follows: mackerel($2.0{\times}10^2-3.2{\times}10^5$, $<5-4.0{\times}10^3CFU/g$), common squid($2.5{\times}10^4-6.6{\times}10^5$, $1.6{\times}10^2-6.0{\times}10^3CFU/g$), shellfish($3.2{\times}10^5-1.7{\times}10^3$, $4.0{\times}10^3-3.0{\times}10\;CFU/g$), boiled fish paste($1.9{\times}10^4$, <5 CFU/g), beef($9.2{\times}10^2-6.4{\times}10^4$, $<5-2.0{\times}10\;CFU/g$), pork($2.6{\times}10^3-1.3{\times}10^6$, $<5-2.7{\times}10^2CFU/g$), chicken($1.0{\times}10^4$, $2.4{\times}10^2CFU/g$), egg($<5-2.3{\times}10^2$, <5 CFU/g), frozen mandu($3.2{\times}10^3-9.5{\times}10^4$, <5 CFU/g), and frozen noodles($<5-9.0{\times}10$, <5 CFU/g). Bacillus cereus($2.0{\times}10\;CFU/g$) and E. coli($1.0{\times}10\;CFU/g$) were detected on shellfish, and Staphylococcus aureuswas detected on pork($3.1{\times}10\;CFU/g$) and chicken($7.8{\times}10\;CFU/g$). Most food items were double-wrapped in vinyl and placed in corrugated cardboard boxes prior to delivery, and the boxes weremixed with other food items when they were put in the vans. There was no cross-contamination during distribution. However, total shellfish bacterial counts increased slightly. These results indicate that foods need to be completely pasteurized during processing. Frozen food items should not be mixed and should be delivered by freezer vans(${\leq}4^{\circ}C$). The number of stops made during distribution/delivery should be reduced.

• Korean Journal of Animal Reproduction
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• v.24 no.3
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• pp.231-239
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• 2000

In this study, we observed the effects of dioxin on weights of body, testes and other organs, the number and motility of sperm in the a various dose after two days' of administration in mice. Animals were treated with oral dose of dioxin 10, 20, 30, 40 mg/kg body weight, respectively. 1, After administration dioxin at doses of 10, 20, 30 and 40 $\mu\textrm{g}$/kg to the mice, the changes in body weights were 30.6 $\pm$ 2.g~40.7 $\pm$ 3.9g and 30.8 $\pm$4.1g~39.5g $\pm$3.1 for 10 and 20 $\mu\textrm{g}$/kg dosed group, 31.0 $\pm$ 3.5g ~ 39.0 $\pm$ 3.5g, 30.6 $\pm$ 3.4g~38.3 $\pm$ 4.0g for 30 and 40 $\mu\textrm{g}$/kg dosed group. The body weight of dioxin-administered group showed lower value when compared to 30.6 $\pm$ 2.8g ~ 44.5 $\pm$ 3.1g of which is control group's. 2. After administration of dioxin at doses of 10, 20, 30 and 40 $\mu\textrm{g}$/kg to the mice, the increase in the number of WBC was prominent, but the increase in the number of RBC wasn't significant, though the values of Hb, PCV, and PLT were higher than those of control group's. 3. After administration of dioxin at doses of 10. 20, 30 and 40 $\mu\textrm{g}$/kg to the mice, the changes in sperm number were 112.5 $\pm$ 3.7~119.4 $\pm$4.2 $\times$ 10$^{6}$ $m\ell$, 103.9 $\pm$3.8 ~ 110.2 $\pm$ 3.6 $\times$ 10$^{6}$ $m\ell$, 97.5 $\pm$ 3.4 ~105.7 $\pm$ 4.4 $\times$ 10$^{6}$ $m\ell$, 87.2 $\pm$ 3.7~98.5 $\pm$ 3.8 $\times$ 10$^{6}$ $m\ell$, respectively. The sperm number of dioxin-administered group showed lower value than that of control group's, which was 119.0 $\pm$ 4.3 ~ 120.7 $\pm$ 4.8 $\times$ 10$^{6}$ $m\ell$. After administration of dioxin at doses of 10~40 $\mu\textrm{g}$/kg to the mice, the sperm motility were 69.4$\pm$ 3.0 ~ 86.6 $\pm$4.7%. The sperm motility of dioxin-administered group showed lower value than that of control group's. 4. After administration of dioxin at doses of 10, 20, 30 and 40$\mu\textrm{g}$/kg to the mice, the organ weight of each dioxin-administered group's was decreased a little compared to that of control group's. 5. After administration of dioxin at doses of 10, 20, 30 and 40 $\mu\textrm{g}$/kg to the mice, the weights of spleen, kidneys, and liver showed increase a little.