• Environmental Engineering Research
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• v.20 no.1
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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.

• Proceedings of the IEEK Conference
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• 2001.10a
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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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• v.54 no.5
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• pp.355-361
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• 2012

The present study was conducted to investigate the effects of concentrate feeding on rumen papillae development in suckling Hanwoo calves before weaning (60 days of age). Twenty-four Hanwoo calves (12 heifers and 12 bulls) at six days of age were randomly assigned to one of three dietary treatments [hay and two levels (low and high) of concentrate feeding] and given each diet with free access to their dams for suckling until 60 days of age. At 60 days of age, two calves from each treatment were sacrificed and used for post-mortem examination of rumen papillae development. Feed intake between 31 and 60 days of age was significantly higher (P<0.05) for the high concentrate treatment (380.2 g/d) than for other treatments (58.3 and 76.9 g/d for hay and low concentrate treatments, respectively). Although feed intake showed a large difference between the low and high concentrate treatments, body weights at birth and 60 days of age were similar between the two treatments, suggesting that calves in the low concentrate feeding suckled more milk from their dams than those in the high concentrate feeding. The ratio of reticulo-rumen weight to body weight at 60 days of age was significantly increased (P<0.05) in the high concentrate (1.39%), compared with those in the hay (0.85%) and low concentrate (1.06%) treatments. Furthermore, the high concentrate feeding significantly increased both rumen papillae length and width, compared with the hay and low concentrate feeding group. This was also detected clearly by visual observation. The blood concentration of ${\beta}$-hydroxybutyrate was significantly higher for the high concentrate (176.4 ${\mu}mol/L$) than for other treatments (58.9 and 59.2 ${\mu}mol/L$ for the hay and the low concentrate group, respectively). In conclusion, the results of the present study showed that, to achieve a large development of rumen papillae before weaning (60 days of age) in suckling Hanwoo calves, the amount of concentrate intake should be important. And also the results implied that hay might not be included in the diet for suckling Hanwoo calves before weaning (60 days of age).

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.2
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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.

• Journal of the Mineralogical Society of Korea
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• v.26 no.1
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• pp.45-54
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• 2013

In order to dissolve Au, Ag, and other valuable metals from gold ore concentrate, raw gold concentrate was pre-treated by roasting and salt-roasting at $750^{\circ}C$. The roasted concentrate was treated with aqua regia digestion to dissolve the valuable metals and higher amount of Au, Ag, and valuable metals were extracted from the roasted concentrates than from the raw concentrate. Higher amount of these metals were also extracted from the salt-roasted concentrate than from the roasted concentrate. The results of the gold dissolution experiments showed that the gold dissolution was most efficient when particle size, roasting temperature, and the percentage of added salt in salt roasting were about $181{\sim}127{\mu}m$, $750^{\circ}C$, and was 20.0%, respectively. The XRD analysis suggests that quartz and pyrite were not destroyed even through roasting at $750^{\circ}C$ and decomposition with aqua regia. However, through salt roasting, pyrite was completely decomposed, whereas quartz could not be destroyed through salt-roasting at $750^{\circ}C$ and aqua regia digestion. Accordingly, it was expected that the gold contained in quartz can not be dissolved through salt-roasting and treatment with aqua regia.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.5
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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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• v.19 no.10
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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.

• Korean journal of food and cookery science
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• v.3 no.2
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• pp.9-16
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• 1987

This study was designed to determine the amino acid composition and to investigate microstructure by scanning electron micrographs of silkworm larvae protein and modified silkworm larvae protein concentrate. The results were as follows: 1, The protein contents of soybean and silkworm larvae protein concentrate were 70.3% and 84.1%, respectively. 2. In general, the essential amino acid content of silkworm larvae protein concentrate were higher than soybean protein concentrate as well as FAO provisional scoring pattern. Silkworm larvae protein concentrate was especially high in lysine and methionine indicating that it could be a good supplemental source for cereals and beans. Succinylation and acetylation resulted in no difference in most amino acid content. 3. The scanning electron microscopic observations revealed that silkworm larvae protein concentrate had smooth surface topography while defatted silkworm larvae flour showed different shapes and sizes with relatively rough surfaces. Acylated silkworm larvae protein concentrate exhibited less cellularity and denser than protein concentrate. However, succinylated silkworm larvae protein concentrate showed especially good texture indicating that it could increase the functional properties of silkworm larvae protein concentrate.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.5
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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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• v.28 no.9
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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.