• 한국환경농학회지
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• 제4권2호
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• pp.78-87
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• 1985

제지(製紙)슬러지가 논 토양(土壤)의 화학성(化學性)과 수도생육(水稻生育)에 미치는 영향(影響)을 검토(檢討)하기 위하여 슬러지의 시용량(施用量)을 300, 600, 900 및 1,200㎏/10a 으로 달리하고 각(各) 시용수준별(施用水準別)로 C/N 율(率)을 30 : 1 로 조절(調節)하여 pot 시험(試驗)을 실시(實施)함으로써 토양중(土壤中) 질소(窒素)의 형태변화(形態變化), 유기태질소(有機態窒素)의 무기성분(無機成分) 및 중금속함량변화(重金屬含量變化)를 경시적(經時的)으로 조사(調査)한 결과(結果)를 요약(要約)하면 다음과 같다. 1) 토양중(土壤中) amino sugar 및 amino acid 태질소(態窒素), 유기물(有機物) CEC 및 유효규산(有效珪酸)의 함량(含量)은 슬러지구(區)가 3요소구(要素區)에 비(比)하여 증가(增加)하였다. 2) 항온(恒溫) 6주후(週後) 유기태질소(有機態窒素)의 무기화율(無機化率)은 3요소구(要素區)가 12.2%, 슬러지 300㎏/10a 구(區) 12.6%, 슬러지 300㎏/10a의 C/N 율조절구(率調節區) 15.1%, 슬러지 600㎏/10a 구(區) 9.7%, 슬러지 600㎏/10a의 C/N 율조절구(率調節區)는 15.2%로 나타났다. 3) 토양중(土壤中) 동(銅) 및 납의 함량(含量)은 각각(各各) $0{\sim}0.2100$ 및 $0{\sim}0.0013$ ppm 범위(範圍)였으며 크롬 및 카드뮴은 검출(檢出)되지 않았고 토양중(土壤中) 이들 중금속함량(重金屬含量)은 처리간(處理間)에 차이(差異)가 없었다.

• 한국환경보건학회지
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• 제29권1호
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• pp.43-50
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• 2003

This study was performed to compare the effects of rice straw and towage sludge cake as bulking materials on temperature, pH, weight and volume reduction, porosity, C/N ratio, salinity, and conductivity in aerobic composting of food wastes. Volume ratios of food wastes to rice straw in reactor control, RS-1, RS-2, RS-3 and RS-4 were 4:0, 4:1, 4:2, 4:3 and 4:4, respectively. Weight ratios of food wastes to sewage sludge rake in reactor control, SL-1, SL-2, SL-3 and SL-4 were 4:0, 4:1, 4:2, 4:3 and 4:4, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The values of pH of food waters, rice straw and sewage sludge cake were 4.39, 7.40 and 5.79, respectively. The lowering of the volume ratio of food wastes to rice straw resulted in the high reaction temperature and the fast weight and volume reduction rates. The lowering of the weight ratio of food wastes to sewage sludge cake resulted in the slow weight and volume reduction rates. C/N ratio in control was larger than that in rice straw containing reactors, and that in rice straw containing reactors was larger than that in sewage sludge cake containing reactors. Salinity and conductivity in reactors were condensed and increased by reaction days.

• 열처리공학회지
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• 제8권4호
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• pp.289-301
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• 1995

The effect of Air/$C_3H_8$ gas addition on the compound layer growth of steels nitrocarburised in $NH_3+Air+C_3H_8$ mixed gas atmospheres was investigated. It is considered that amount of residual $NH_3$ was varied according to alternation of Air/$C_3H_8$ mixing ratio and volume content. The compound layer formed from nitrocarburising was composed of ${\varepsilon}-Fe_{2-3}$(C, N) and ${\gamma}^{\prime}-Fe_4$(C, N). According as Air/$C_3H_8$ mixing ratio increased, the superficial content of ${\gamma}^{\prime}-Fe_4$(C, N) within the compound layer was increased, at the same time the growth rate of compound layer and porous layer was increased. In the case of alloy steel at the fixed gas composition, the growth rate of compound layer and porous layer was worse than carbon steel and compound layer phase composition structure primarily consisted of E phase. As the carbon content of materials was increasing in the given gas atmospheres, the growth rate of compound layer and porous layer was increased and the superficial content of ${\varepsilon}-Fe_{2-3}$(C, N) within the compound layer was increased.

• KSBB Journal
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• 제16권2호
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• pp.140-145
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• 2001

To treat piggery wastewater containing refractory compounds including nitrogen, physical treatments using zeolite and biological processes were investigated. In biogical treatment, the removal efficiencies of organics and nitrogen in bioreador using BACC (Biological Activated Carbon Cartridge) media filled with granule activated carbon were examined. The best removal efficiencies achieved for TKN and COD(sub)cr were 82% and 53% respectively, when zeolite dosage was 300 g/L. Specific nitrogen removal ability was 3.2 mg/g at a zeolite dosage of 50 g/L, whereas specific nitrogen removal ability was 1.8 mg/g at a zeolite dosage of 300 g/L. The increased of C/N ratio resulting from the removal of nitrogen using zeolite led to an increase in removal efficiency of organics. As C/N ratio was increased to 2.0, 2.44 and 6.58 at a HRT of 48 hours in a BACC bioreactor, removal efficiencies of COD(sub)cr were increased to 53.5%, 57.4% and 80.6%. The removal efficiency of wastewater using a zeolite dosage of 399 g/L was increased by 27.1% compared to that of control treatment.

• Journal of Acupuncture Research
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• 제33권3호
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• pp.1-16
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• 2016

Objectives : The objective of this study was to investigate the effects of Gentianae Macrophyllae Radix pharmacopuncture (GP) at Hwando (GB30) in neuropathic pain induced rats. Methods : Neuropathic pain in rats was induced by tibial and sural nerve transection. The rat subjects were divided into 6 groups : normal (Nor, n = 5), control (Con, n = 5), neuropathic pain- induced injected at GB30 with 1 mg/kg GP (GP-A, n = 5), 5 mg/kg GP (GP-B, n = 5) and 20 mg/kg GP (GP-C, n = 5), and neuropathic pain-induced injected with 1mg/kg Tramadol (Tramadol, n＝5). Injections were administered 2 times a week for a total of 5 treatments. After each treatment plantar withdrawal response was measured and after all 5 treatments were completed c-fos, Bax, Bcl-2, mGlu5 and leukocytes in the blood were analyzed. Results : 1. Groups GP-A, GP-B and GP-C showed a meaningful decrease in the withdrawal response of mechanical allodynia compared to the control group. 2. Groups GP-A, GP-B and GP-C showed a meaningful decrease in the expression of c-fos compared to the control group. 3. Groups GP-A and GP-C showed a meaningful increase in the expression of mGluR5 compared to the control group. 4. Groups GP-A, GP-B and GP-C showed a meaningful decrease in Bax/Bcl-2 ratio compared to the control group. Conclusion : These results suggest that Gentianae Macrophyllae Radix pharmacopuncture at Hwando (GB30) could decrease mechanical allodynia and could have analgesic and neuroprotective effects on the model of neuropathic pain.

• Environmental Engineering Research
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• 제19권1호
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• pp.47-57
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• 2014

The aim of this paper was to study the effect of five different waste combinations (C/N 15, C/N 20, C/N 25, C/N 30, and control) of sewage sludge coupled with sawdust and cattle manure in a pilot scale rotary drum reactor, during 20 days of the composting process. Our results showed that C/N 30 possesses a higher temperature regime with higher % reduction in moisture content, total organic carbon, soluble biochemical oxygen demand and chemical oxygen demand; and higher % gain in total nitrogen and phosphorus at the end of the composting period implying the total amount of biodegradable organic material is stabilized. In addition, $CO_2$ evolution and oxygen uptake rate decreased during the process, reflecting the stable behavior of the final compost. A Solvita maturity index of 8 indicated that the compost was stable and ready for usage as a soil conditioner. The results indicated that composting can be an alternate technology for the management of sewage sludge disposal.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 추계학술대회 논문집
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• pp.302-305
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• 2007

In recent years, many researches on new storage media with high capacity and information are developing. For manufacture of optical storage with high capacity, the injection molding process is generally used. In order to increase the filling ratio of the injection molding structure, the injection molding process required for high injection pressure, packing pressure and temperature control of the mold. However, conventional injection molding process is difficult to increase the filling ratio using injection master with the range of several nanometers and high aspect ratio. In order to improve and increase filling ratio of nano-structure with high aspect ratio, the active temperature control of injection mold was used. Experimental conditions were used injection pressure, time and temperature. Consequently, by using the peltier device into injection mold, we carried out the efficient and active temperature control of mold at low cost.

• 한국세라믹학회지
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• 제29권9호
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• pp.681-688
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• 1992

Ultrafine Si3N4 and Si3N4+SiC mixed powders were synthesized through thermal plasma chemical vapor deposition(CVD) using a hybrid plasma, which was characterized by the supersposition of a radio-frequency plasma and arc jet. The reactant SiCl4 was injected into an arc jet and completely decomposed in a hybrid plasma, and the second reactant CH4 and/or NH3 mixed with H2 were injected into the tail flame through double stage ring slits. In the case of ultrafine Si3N4 powder synthesis, reaction efficiency increased significantly by double stage injection compared to single stage one, although crystallizing behaviors depended upon injection speed of reactive quenching gas (NH3+N2) and injection method. For the preparation of Si2N4+SiC mixed powders, N/C composition ratio could be controlled by regulating the injection speed of NH3 and/or CH4 reactant and H2 quenching gas mixtures as well as by adjusting the reaction space.

• Asian-Australasian Journal of Animal Sciences
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• 제32권6호
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• pp.767-775
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• 2019

Objective: The purpose of this study was to evaluate the effect of rapeseed and linseed oil supplementations on performance and meat quality of lambs. Methods: The experiment was conducted on 18 growing (100-day-old) lambs of $19.7{\pm}1.9kg$ live weight, assigned to 3 groups of 6 animals each. Control lambs were fed meadow hay and concentrate alone. Experimental animals additionally received rapeseed or linseed oils at a dose of 50 g/d. The lambs were slaughtered at an average body weight of $35.7{\pm}0.5kg$. Results: The dressing percentage was higher in lambs fed rapeseed oil. Total saturated fatty acids (SFA) and C15:0, C16:0, C17:0, C21:0, C24:0 were lower in longissimus dorsi muscle (MLD) in lambs fed linseed oil. Supplementation of diet with linseed oil decreased concentrations of total monounsaturated fatty acids and C16:1, C17:1, C18:1 cis-9 in MLD. The concentrations of n-3 polyunsaturated fatty acids (PUFA) and C18:3 n-3, C20:5 n-3 in MLD were higher in lambs fed linseed oil than in other groups. Oils supplementation to diets resulted in increased concentration of C22:6 n-3 in MLD. The inclusion of linseed oil into the diet increased the contents of total PUFA, n-3 PUFA and C18:3 n-3, C20:5 n-3, C22:6 n-3 in semitendinosus muscle in comparison to control. A tendency towards a lower n:6/n:3 ratio in MLD was observed when lambs were supplemented linseed oil. Conclusion: The supplementation of linseed oil to diets seems to reduce the concentration of SFA and increase the concentration of n-3 PUFA. The n-6/n-3 ratio is an important nutritional factor, and its value has been favorably decreased below 2, thereby achieving an important target related to human health. Due to these changes carcass fatty acid profile was improved, and so enhanced lamb meat healthy properties.

• 유기물자원화
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• 제2권1호
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• pp.75-86
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• 1994

우리나라에서 발생되는 음식쓰레기는 퇴비화 처리시 높은 수분함량과 낮은 C/N비를 적정 수준으로 조절하기 위해 bulking agent를 첨가함이 필수적이며 그의 정확한 첨가량을 계산하는 것은 퇴비화에 소요되는 비용을 결정하는데 중요한 요소로 적용하게 된다(Hay et al., 1998). 그러나 bulking agent의 첨가량을 계산하기 위한 기준지표 중의 하나인 C/N비의 경우 혼합되는 bulking agent의 분해정도가 고려되지 않은 총 탄소와 질소의 비에 기준하여 적정 첨가비율이 정해지고 있기 때문에 실제 요구되는 탄소와 질소의 양을 초과 또는 미달하는 경우가 발생될 수 있으며, 이는 곧 bulking agent의 과다첨가 또는 반응속도 저하로 인한 처리비용의 상승과 직결될 수 있다. 본 연구에서는 음식쓰레기의 퇴비화를 위한 bulking agent의 정확한 첨가량을 정량적으로 제시하기 위하여 bulking agent의 첨가로 인한 반응향상 여부와 그 원인을 분석하여 이를 바탕으로 적정 첨가량 결정법을 제안하였다. 그 결과 실질적으로 분해가능한 탄소원을 포함하고 있는 쌀밥의 첨가는 C/N비가 낮은 음식쓰레기의 퇴비화반응을 향상시킬 수 있으나, 분해가 쉽지 않은 톱밥을 bulking agent로 첨가할 경우는 음식쓰레기의 탄소원을 제공함으로써 반응을 향상시킨다기 보다는 음식쓰레기의 통기성을 개선하여 줌으로써 활발한 퇴비화 반응을 유도한다는 사실을 확인할 수 있었다. 따라서, bulking agent는 그 첨가량을 많이 할수록 퇴비화반응에 유리하며, 일반적인 적정 C/N비값 이상의 첨가율에서도 반응 향상이 가능한 것으로 예상된다. 또한 bulking agent 첨가량의 증가로 인한 통기성의 향상효과는 해당 조건하에서의 적정 수분함량값 증가요소로 작용하는 것으로 나타나 이를 종합적으로 고려한 bulking agent첨가량 결정이 필요함을 알 수 있었다. 이상과 같은 실험적 분석의 결과를 종합할 때, 음식쓰레기 100g당 78g의 톱밥을 첨가하여 C/N비를 25 수분함량을 56%로 각각 조절하는 것이 본 연구에서 다루어진 음식쓰레기의 활발한 퇴비화를 위해서는 적절하며, 이러한 첨가량의 계산법은 실제 퇴비화시설의 적정 운전을 위해서 적용함이 바람직한 것으로 판단되었다.