• Environmental Engineering Research
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• 제20권1호
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• pp.99-104
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• 2015

The purpose of this study is to evaluate the performance of forward osmosis (FO) system for harvesting microalgae cultivated in secondary sewage effluent. Microalgae species used in this study were chlorella sp. ADE4. The drawing agents used for forward osmosis system were seawater and concentrate of sea water reverse osmosis (SWRO) system. Chlorella sp. ADE4 cultured in secondary sewage effluent illustrated moderate efficiency in removal of total nitrogen (TN) (68%) and superior performance in total phosphorus (TP) removal (99%). Comparison of seawater and SWRO concentrate as drawing agent were made in FO membrane separation of the microalgae. The result from this study depicts that SWRO concentrate is strong drawing agent in FO membrane system providing an average dewatering rate of $4.8L/(m^2{\cdot}hr)$ compared to seawater with average dewatering of $2.9L/(m^2{\cdot}hr)$. Results obtained from this study indicated that FO system could be viable option for harvesting the microalgae for further biodiesel production. SWRO concentrate as a drawing agent could be very important finding in field of membrane technology for disposal of SWRO concentrate.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.159-164
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• 2001

A novel fluidized-bed reactor was designed and installed for bioleaching in a semi-continuous way, by which a process for bioleaching-cyanidation of Guangxi Jinya refractory gold arsenical concentrate was studied. An arsenic extraction rate reaches 82.5% after 4-day batch biooxidation of the concentrate under the optimized condition of pH 2.0, ftrric ion concentration 6.5g/L and pulp concentration 10%. And leaching rate of gold in the following gold cyanidation is over 90%. The parameters of three series fluid-bed reactors exhibit stability during the semi-continuous bioleaching of the concentrate. Arsenic in the concentrate can be got rid of 91% after 6-day leaching. Even after 4 days, 82% of arsenic extraction rate was still obtained. The recovery rates of gold are 92% and 87.5% respectively in cyaniding the above bioleached residues. The results will provide a base for further commercial production of gold development.

• Journal of Animal Science and Technology
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• 제54권5호
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• pp.355-361
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• 2012

본 연구는 이유 (생후 2개월) 전 농후사료 (무조사료) 급여가 한우 어린 송아지의 반추위 유두 발달에 미치는 영향을 조사하기 위하여 수행하였다. 총 24두 (수 12두, 암 12두)의 생후 6일령 한우 어린송아지를 3처리구에 배치하였고, 각각 어미젖을 포유할 수 있는 시설에서 사육하였다. 처리구는 크게 농후사료구 (무조사료구)와 조사료구로 구분하였고, 농후사료구는 농후사료의 섭취량에 따른 반추위 발달 양상을 조사하기 위하여, 사료섭취량을 기준으로 고농후사료급여구와 저농후사료급여구로 세분화하였다. 31~60일령의 1일 사료 섭취량은 고농후사료급여구 (380.2 g/d)가 저농후사료급여구 (76.9 g/d) 및 조사료구 (58.3 g/d)에 비하여 유의적 (P<0.05)으로 높았다. 고농후사료급여구와 저농후사료급여구의 1일 사료섭취량은 큰 차이를 보였지만 생시체중 및 60일령 체중은 비슷하게 나타나, 저농후사료급여구의 성장에 부족한 영양분은 어미소의 포유로부터 충족된 것으로 사료되었다. 60일령의 체중 대비 반추위 무게의 비율은 고농후사료급여구 (1.39%)가 저농후사료급여구 (1.06%) 및 조사료구 (0.85%) 보다 유의적 (P<0.05)으로 높게 나타났다. 뿐만 아니라 고농후사료급여구의 반추위 유두 길이 및 두께도 다른 처리구들에 비하여 유의적 (P<0.05)으로 높았다. 이는 육안으로도 그 차이를 뚜렷이 구분할 수 있었다. 60일령 혈중 ${\beta}$-hydroxybutyrate의 농도도 고농후사료급여구 (176.4 ${\mu}mol/L$)가 저농후사료급여구 (59.2 ${\mu}mol/L$) 및 조사료구 (58.9 ${\mu}mol/L$) 보다 유의적 (P<0.05)으로 높았다. 본 연구의 결과는 이유 전 (생후 2개월) 한우 송아지의 반추위 발달이 농후사료 섭취량에 의하여 크게 영향을 받으며, 우유와 조사료는 반추위 발달에 미치는 영향이 매우 낮음을 제시하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제26권2호
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• pp.202-210
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• 2013

This study elucidated the effects of limited concentrate feeding on growth, plasma profile, and gene expression of gluconeogenic enzymes and visfatin in the liver of Hanwoo beef calves. The purpose of this study was to test that reducing the amount of concentrate would partially be compensated by increasing the intake of forage and by altering the metabolic status. The study utilized 20 Korean native beef calves (Hanwoo; 60 to 70 d of age) divided into two groups of 10 calves each for 158 d. Control group calves received the amount of concentrate as per the established Korean feeding standards for Hanwoo, whereas calves in the restricted group only received half the amount of concentrate as per standard requirements. Good quality forage (Timothy hay) was available for ad libitum consumption to both groups. Since calves were with their dam until 4 months of age in breeding pens before weaning, the intake of milk before weaning was not recorded, however, the concentrate and forage intakes were recorded daily. Body weights (BW) were recorded at start and on 10 d interval. Blood samples were collected at start and at 50 d interval. On the final day of the experiment, liver biopsies were collected from all animals in each group. The BW was not different between the groups at all times, but tended to be higher (p = 0.061) only at final BW in control than restricted group. Total BW gain in the control group was 116.2 kg as opposed to 84.1 kg in restricted group that led to average BW gain of 736 g/d and 532 g/d in respective groups, and the differences were significant (p<0.01). As planned, the calves in the control group had higher concentrate and lower forage intake than the restricted group. The plasma variables like total protein and urea were higher (p<0.05) in control than restricted group. The mRNA expressions for the gluconeogenic enzymes such as cytosolic phosphoenol pyruvate carboxykinase (EC 4.1.1.32) and pyruvate carboxylase (EC 6.4.1.1), and visfatin measured by quantitative real-time PCR in liver biopsies showed higher expression (p<0.05) in restricted group than control. Overall, restricting concentrate severely reduced the growth intensity and affected few plasma indices, and gene expression in liver was increased indicating that restricting concentrate in the feeding schemes during early growth for beef calves is not advocated.

• 한국광물학회지
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• 제26권1호
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• pp.45-54
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• 2013

금정광에 함유된 금, 은 및 유용금속을 효과적으로 용해시키기 위해서 비가시성 금정광을 소성 및 소금소성처리하였다. 이들 소성처리 생성물에 대하여 왕수분해 결과 금, 은 및 유용금속 함량은 비가시성 정광에서보다 소성정광에서, 그리고 소성정광에서 보다 소금소성정광에서 더 많이 용해되었다. 금과 은이 최대로 용해되는 입도는 $181{\sim}127{\mu}m$, $750^{\circ}C$의 소성온도, 그리고 20%의 소금첨가량에서였다. XRD 분석을 수행한 결과, 석영과 황철석은 $750^{\circ}C$의 소성처리, 그리고 왕수분해에도 불구하고 분해되지 않았다. 황철석은 소금소성처리에 의하여 완전하게 분해되었지만 석영은 파괴되지 않았다. 따라서 석영에 함유된 금은 소금소성처리나 왕수분해를 수행해도 용해되지 않을 것으로 예상된다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권5호
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• pp.600-604
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• 2000

Exp. I, the study was conducted to examine the supplementation levels of cassava hay (CH) in dairy cows. Six multiparous Holstein-Friesian crossbreds were paired and randomly assigned in a change-over design to receive three levels of CH supplement at 0, 0.8 and 1.7 kg DM/hd/d. Concentrate was supplemented at the same level (1:2; concentrate:milk yield) while urea-treated (5%) rice straw was offered on ad libitum basis. The results revealed that supplementation of CH could significantly reduce concentrate use resulting in similar milk yield (12.5, 12.12 and 12.6 kg/hd/d) and significantly enhanced 3.5% FCM (14.21, 15.70, 14.9 kg/d, respectively). Moreover, CH supplementation significantly increased milk fat and milk protein percentages especially at 1.70 kg/hd/d. Concentrate use could be significantly reduced by 27% at 1.7 kg/hd/d CH supplementation. Exp. II, supplementation of cassava hay to replace concentrate use was studied in lactating-Holstein Friesian crossbreds grazed on Ruzi grass. Six multiparous cows in mid-lactating periods were paired and randomly assiged according to a change-over-design to receive three dietary treatments, $T_1=0kg$ cassava hay (CH) in 1:2 concentrate supplementation (CS) to milk yield (MY), $T_2=1.0kg$ DM CH/hd/d in 1:3 CS to MY, $T_3=1.7kg$ DM CH/hd/d in 1:4 CS to MY, respectively. The results were found that milk yield were similar among treatments while protein, lactose and solids-not-fat percentages were highest (p<0.05) in cows receiving CH at 1.0 kgjhd/d. Most significant improvement from CH supplementation was the ability to reduce concentrate use by 42% which could provide a higher income for small-holder dairy farmers. In addition, milk thiocyanate was enhanced from 5.3 to 17.8 ppm (p<0.05) in the control and in the CH supplemented group (1.7 kg/hd/d), respectively. Moreover, CH supplementation could significantly reduce concentrate level for diary feeding thus resulted in more economical return. Cassava hay demonstrated as a potential and high-quality on-farm feed resource especially for dry season feeding in the tropics.

• Asian-Australasian Journal of Animal Sciences
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• 제19권10호
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• pp.1455-1463
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• 2006

Effects of different levels of molasses in a concentrate supplement on milk yield of cows grazing Setaria grass pastures were investigated. Thirty Friesian cows, 6-7 years old with mean pre-experimental body weight of $428{\pm}6.5$ kg, in early stage of lactation were randomly allotted to five dietary treatments in a completely randomized design experiment that lasted for 126 days. Experimental dietary treatments were forage alone and forage/concentrate mixtures with molasses included at 0, 5, 10 or 15% levels designated as $T_1$, $T_2$, $T_3$, $T_4$ and $T_5$, respectively. The parameters studied were voluntary dry matter (DM) intake, average daily live weight change (LWC), milk yield, body condition score (BCS) and apparent nutrient digestibility coefficients. The DM and energy contents of Setaria grass were low compared to the concentrate diets. Fibre fractions-NDF, ADF, ADL, hemicellulose and cellulose; and gross energy were higher in concentrate mixtures than in the forage. Total DM intake (forage+concentrate mixtures) was significantly higher (p<0.001) in cows on the concentrate mixtures. LWC was not significantly different (p>0.05) between the cows. Average milk yields were significantly different (p<0.05) between cows. Fat corrected milk (FCM) was similar among cows in the treatments. BCS was better (p<0.001) in cows on concentrate mixtures. Digestibilities of DM, CP, NDF, ADF, ADL, OM, and energy were significantly higher (p<0.001) in cows on $T_2$, $T_3$, $T_4$ and $T_5$ than in those on $T_1$. There were no significant differences in the digestibility of DM, CP, NDF, ADF and ADL (p>0.001) in cows on concentrate mixtures. This study therefore demonstrated that lactating dairy cows in Fiji need a level of readily fermented energy source such as molasses in their diets; however, a level above 10% is not nutritionally suitable for lactating dairy cows. Based on data on production parameters-milk yield, fat corrected milk, body condition score and apparent nutrient digestibility coefficients-molasses levels that range between 5-10% are recommended, however, 10% is the best and therefore recommended for inclusion in the concentrate mixture of lactating dairy cows on a basal diet of Setaria sphacelata in Fiji.

• 한국식품조리과학회지
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• 제3권2호
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• pp.9-16
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• 1987

제사공장에서 부산물로 나오는 번데기는 단백질의 함량이 높을 뿐 아니라 필수 아미노산 조성도 우수하여 영양적으로 좋은 단백질원으로 알려져 있다. 이에 번데기로 농축단백질을 조제해서 무수초산과 호박산으로 아실화시켜 아미노산조성 및 주사전자현미경에 의한 관찰을 대두농축단백질과 비교 검토하여 다음과 같은 결과를 얻었다. 1. 번데기 농축단백질의 단백질 함량은 84.1%로서 대두농축단백질의 70.3%보다 높았다. 2. 번데기 농축단백질은 아미노산 조성에 있어서 대두농축단백질보다 필수 아미노산 함량이 높았으며 특히 대두에 부족한 methionine은 4.21(g/100g)로 매우 높았고, F.A.O.의 scoring pattern과 비교시 전체적으로 필수 아미노산이 함량이 높았다. 또한 번데기 농축단백질은 alanine, valine, phenylanine, isoleucine 등 지방족 아미노산의 함량이 높게 나타났다. 한편 변형번데기단백질에서는 아미노산의 함량에 약간의 손실을 가져왔으며 숙시닐화에서 더 큰 경향을 나타내었고 특히 lysine의 함량이 현저하게 감소되었다. 3. 주사전자현미경에 의한 관찰에서 탈지번데기분은 작고 입자가 많이 모여 하나의 agglomerate의 형태로 거칠고 세포성이 그대로 보존되어 있다. 기포의 생성이 많았으며 입자가 불균일(10~$20\mu{m}$)하였다. 번데기 농축단백질은 탈지번데기분보다 세포성이 많이 파괴되어 기포의 생성도 적어 입자의 표면적이 어느정도 넓고 부드러웠다. 또한 변형번데기농축단백질에서는 현저하게 세포성이 파괴되고 가 감소하여 좋은 조직을 형성하였으며 특히 숙시닐화한 단백질에서는 아주 부드럽고 좋은 조직을 나타내었다.

• Asian-Australasian Journal of Animal Sciences
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• 제15권5호
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• pp.650-657
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• 2002

Two experiments were conducted to evaluate the effects of forage:concentrate ratios and feeding principles on milk yield, milk composition, body weight change, postpartum oestrus and feed cost. A total of 36 crossbred F1 cows (Holstein Friesian${\times}$Local Yellow) in the 8th week of lactation were used. In each experiment, animals were divided into three groups using a randomized block design according to the milk yield of the previous eight weeks. Cows were fed 30, 50 and 70% concentrate in the diet based on DM. In experiment 1 (Fc), cows were given the same amount of DM with constant ratios of forage and concentrate within treatments. In experiment 2 (Fa), cows were given the same constant amounts of concentrate as in experiment 1 and ad libitum forage. The forage consisted of a natural grass mixture based on 5 species of grasses with high nutritive values. There was no difference in total DM intake between treatments within experiments. However, cows fed forage ad libitum had higher DM intakes compared to cows fed constant forage (1.6, 4.5 and 9.5% for cows fed 70, 50 and 30% forage, respectively). Daily milk yield of cows fed forage ad libitum was higher than that of cows fed constant forage:concentrate ratio. Within experiment, milk yield was highest for cows fed 30% DM forage, followed by cows fed 50% and then cows fed 70% forage (11.17, 10.98 and 10.71 for the 30Fc, 50Fc and 70Fc cows; 11.73, 11.16 and 10.81 kg for the 30Fa, 50Fa and 70Fa cows, respectively). Decreased forage ratio in the diets resulted in decreased milk fat content and tended to increase milk protein. Increased concentrate ratio in the diet and feeding forage ad libitum increased body weight gain. The effect of forage:concentrate ratio on postpartum oestrus was not significant. The feed cost per kg milk produced was lowest for the cows fed 70% forage. It is concluded that increased ratio of concentrate resulted in increased body weight gain, milk yield, milk protein, and decreased milk fat. Feeding forage ad libitum increased feed intake, milk yield and body weight gain. The ratio of 50% forage is more suitable for milk production and animal condition, but in terms of feed cost and under the conditions of small dairy farmers, the 70% ad libitum forage feeding is recommended.

• Asian-Australasian Journal of Animal Sciences
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• 제28권9호
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• pp.1309-1316
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• 2015

In this paper, weight, carcass dressing, weights of the primary cuts, weights of the physical components of the primary cuts, and weights of the main commercial cuts of 66 $Purun{\tilde{a}}$ animals, of which 33 were bulls and 33 were steers were evaluated. These animals, with an average age of 19 months at the beginning of the experiment, were finished in a feedlot system during 116 days, and were fed with diets containing three levels of concentrate (0.8%, 1.1%, and 1.4% of body weight). The concentrate was formulated with 25% soybean meal, 73% ground corn grain, 1% of a mineral mix, and 1% of limestone. The interaction between sexual groups and the concentrate level was not significant for any of the variables. Likewise, no effect of the concentrate level was detected on the same variable traits. The bulls demonstrated higher hot carcass weights (265.1 vs 221.7 kg) and a higher proportion of forequarter (38.4% vs 36.1%) however the steers presented with higher proportions of side (19.7% vs 18.5%) and hindquarter (44.2% vs 43.1%). The bulls produced higher yields of muscle in the three primary cuts, there by resulting in higher yields of edible portions of the carcass. The bulls also produced higher weights of tenderloin, knuckle, topside, flat, eye round, rump, and rump cover. The finishing of young bulls in feedlot is to be recommended, since the animals produce carcasses with higher amounts of edible meat and higher yields of commercial cuts, thus allowing for a better price for the carcass. Low concentrate level could be used due to the lower cost of production for farmers.