• Resources Recycling
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• v.4 no.3
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• pp.19-25
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• 1995

A Study on the recovery of the valuable metals(Vanadium Molybdenium) was carried out using spent catalysts originated from desulfurizing process of oil refinery. Experiments consisted of pre-roasting for Sulfur and Carbon removal, soda roasting and leaching for the extraction of valuable metals, and selective precipitation of Vanadium and Molybdenium. Effects of temperature and time in roasting for Sulfur removal, of $Na_2CO_3$ concentrations in soda roasting, and of pulp density, temperature and time in leaching were investigated for the recovery of Vanadium and Molybdenium. A optimum condition having over 85% in yield of Vanadium and Molybdenium was found. In the selective precipitation, more than 98% of Vanadium and Molybdenium were obtained by the variation of pH and concentration of additives.

• Transactions of Materials Processing
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• v.30 no.2
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• pp.61-68
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• 2021

As part of efforts to reduce the weight of automotive body-in-white, a hybrid center pillar with high strength 7075 aluminum alloy (AA7075) sheet and carbon fiber reinforced plastic (CFRP) has been recently studied. In the fabrication of the AA7075-CFRP hybrid center pillar, the AA7075 sheet might go through heating-forming-in-die quenching (HFQ), artificial aging, hybridizing, and then paint baking processes. In this study, we investigate the effects of the heat treatment history associated with each process on the tensile strength of the AA7075 sheet. Typical heat treatment conditions are HFQ for 20 minutes at 480℃ and then cooling down with die, artificial aging of T6 temper for 24 hours at 120℃, hybridizing for 10 minutes at 150℃, and paint baking for 20 minutes at 180℃. The tensile strength of the AA7075 sheet is continuously increased by a series of heat treatments of hybridizing and paint baking and is expected to have yield stress above 500MPa without artificial aging of T6 temper.

• Journal of the Korea Organic Resources Recycling Association
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• v.2 no.2
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• pp.53-63
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• 1994

In order to investigate the effects of application rates of mineral N and cattle slurry on the dry matter yield of Reed canarygrass grown in different cutting frequency, was was cernpared for the efficiency of N utilization. Annual rates of mineral N and cattle slurry N of 0 (control), 90kg, 180kg, 270kg and 360kg/ha in 3 cuttings, 0, 120kg, 240kg, 360kg and 480kg/ha in 4 cuttings, and 0, 150kg, 300kg, 450kg and 600kg/ha were applied as urea and cattle slurry in 5 cuttings, respectively. The results were summarized as follows: 1. The annual dry matter yields were increased with application rates of mineral N and cattle slurry. The annual dry matter yields of mineral N obtained were 14.4 ton/ha(ranged from 10.46 ton to 16.91 ton/ha) in 3 cuttings, 13.88 ton/ha(ranged from 9.91 ton to 16.53 ton/ha) in 4 cuttings and 15.98 ton/ha(ranged from 12.0 ton to 18.25 ton/ha) in 5 cuttings. The annual dry matter yields of cattle slurry obtained were 12.14ton/ha(ranged from 8.92 ton to 11.79ton/ha) in 3 cuttings, 10.81ton/ha(ranged from 8.92 to 11.79 ton/ha) in 4 cuttings and 12.98ton/ha(ranged from 10.68 ton to 14.85ton/ha) in 5 cuttings. 2. Relative dry matter yield of cattle slurry as compared to mineral N were 84.3%, 77.9% and 81.2% in 3, 4 and 5 cuttings. 3. Average increase in dry matter production(kgDM/kgN) tended to decrease with application rates of mineral N and cattle slurry, and higher cutting frequencies. Average increase in dry matter production obtained were higher values at rates of 30kg/ha/cut in both of mineral N and cattle slurry. Average increase in dry matter production to mineral N were 23.9kg, 18.8kg and 15.2kgin 3, 4 and 5 cuttings, respectively. 4. Average increase in total nitrogen yield(kgTN/kgN) to mineral N obtained were 0.46kg at rates of 60kg/ha/cut in 3 cuttings, and 0.45kg and 0.40kg at rates of 30kg/ha/cut in 4 and 5 cuttings. 5. Average increase in dry matter production(kgDM/kgN) to cattle slurry obtained were 13.7kg and 19.5kg at rates of 30kg/ha/cut in 3 and 4 cuttings, and 9.7kg at rates of 60kg/ha/cut in 5 cuttings. 6. Average increase in total nitrogen yield(kgTN/kgN) to cattle slurry was not concern to the rates of application. Average increase in total nitrogen yield to cattle slurry obtained were 0.11kg, 0.20kg and 0.21kg in 3, 4 and 5 cuttings. 7. Relative average increase in dry matter production of cattle slurry as compared to mineral N were 33.1%, 52.1% and 50.0% in 3, 4 and 5 cuttings. Relative average increase in total nitrogen yield of cattle slurry as compared to mineral N were 28.9%, 51.3% and 55.3% in 3, 4 and 5 cuttings.

• Journal of Animal Science and Technology
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• v.47 no.5
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• pp.899-904
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• 2005

The study was conducted to investigate the effects of physical stimulus on casting day of antler, velvet antler yield, length of velvet antler in Sika deer(Cervus nippon). Eigthen(18) stags were assigned into the treatment with six(6) stags for treatment. Results revealed that at the start of the velvet antler growth, compulsorily casting both pedicles group was 15 days later at first cycle but 11-14 days earlier at the second cycle than control group(P<0.05). The yields of velvet antler in control group, casting only left pedicle group and the both pedicle group were 775g, 835g and 757g at the first cycle and 1,004g, 1,194g and 998g at the second cycle, respectively. The average length of antler in control group, casting only left pedicle group and both pedicle group were 25.8cm, 27.4cm and 31.5cm, respectively. The average length of antler of the casting only left pedicle group and that of the both pedicle group showed 1.6cm and 5.7cm in first cycle and 2.7cm and 2.4cm in second cycle longer than that of control group(P<0.05). Results of the study suggest the possibility of controlling velvet antler producing point through compulsory casting method.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.5
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• pp.595-599
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• 2000

Fine wool sheep (n=18) maintained in a tropical environment were allocated to three treatment groups. Estrus was induced with two injections of $PGF_{2{\alpha}}$ (10 mg. im) at 10 days interval. Superovulation treatment started 2 days prior to the second injection of $PGF_{2{\alpha}}$. Each ewe was treated with a total dose of 25 units FSH (Super-OV) i.m. every 12 hover 3 days; Group 2 were also injected i.m. with 200 IU PMSG at the first injection of FSH; Group 3 was treated as in Group 2 and also with GnRH ($4{\mu}g$ Buserelin) at the onset of estrus. The ewes in estrus were mated with a fertile ram. Ovarian examination and recovery of embryo and ova were performed at laparoscopy and laparotomy on day 3 or 4 after mating. Data for onset of estrus, duration of estrus, number of corpora lutea (CL), number of unnovulated large follicle (LF), embryo recovery rate, embryo quality and fertilization recorded for the 3 groups. Ewes in the Group 1 set in estrus later (p<0.05; $50.0{\pm}7.29h$) than the ewes in Group 2 ($24.5{\pm}3.58$) and 3 ($32.5{\pm}3.58h$). The duration of estrus, ovarian size and ovarian response (number of CL and LF) did not differ significantly (p>0.05) among the 3 groups. The proportion of ewes with a superovulatory response (${\geq}2$ CL) was the lowest (50%) in Group 1 treated with FSH alone but ova/embryo recovery (100%) and fertilization (100%) was significantly (p<0.05) higher than Group 2 (58.3 and 85.7%, respectively) and Group 3 (48.6 and 50%, respectively). It is concluded that in tropical fine wool sheep, there is no difference in the 3 treatments for yield of good quality embryos but ovarian response and ovulation rate increased on additional use of PMSG and GnRH respectively to FSH alone.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2962-2968
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• 2009

The photodissociation dynamics of 1,2-bromochloroethane ($C_2H_4BrCl$) was investigated near 234 nm. A two-dimensional photofragment ion-imaging technique coupled with a [2+1] resonance-enhanced multiphoton ionization scheme was utilized to obtain speed and angular distributions of the nascent Br($^2P_{3/2}$) and Br${\ast}($^2P_{1/2}$) atoms. The total translational energy distributions for the Br and Br${\ast}$ channels were well characterized by Gaussian functions with average translational energies of 100 and 84 kJ/mol, respectively. The recoil anisotropies for the Br and Br${\ast}$ channels were measured to be ${\beta}$ = 0.49 ${\pm}$ 0.05 for Br and 1.55 ${\pm}$ 0.05 for Br${\ast}$. The relative quantum yield for Br${\ast}$ was found to be ${\Phi}_{Br{\ast}}$ = 0.33 ${\pm}$ 0.03. The probability of nonadiabatic transition between A' states was estimated to be 0.46. The relevant nonadiabatic dynamics is discussed in terms of interaction between potential energy surfaces in Cs symmetry.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.2
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• pp.161-168
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• 1987

This study was conducted to evaluate the effects of potassium and sulfur power levels on the growth, nutrients' uptake at different growing stage and seed yield of peanut plant and changes of soil chamical properties in a sandy peanut cultivated soil of Nak-dong riverside in 1984. 1. The length of main stem, that of branch NO. and NO. of branches per plant were increased by the increased application of potassium and sulfur powdar. Especially sulfur powder treated plot were shown in positive effect with obtained in main root length, NO. of roots and Wt. of noudles formed per plant, roots' weight of peanut plant was much more than top's Wt. at harvesting stage, and so ratio of dry matter Wt. top/root was low. 2. The noudle's Wt. formed was positively significant recognized with dry matter Wt. of peanut plant at harvesting stage and the treatments of potassium were increased 7-20% compared with potassium non-treated plot and sulfur's treatments were increased 4-13% than that of potassium 15kg/10a treatment which was sulfur's non-treated plot in seed yield. 3. Relationship between all nutrients' uptake at flowering stage and seed yield were positively significant recognized, but $P_2O_5$ uptake and N/S ratio showed negative effect at harvesting stage of peanut plant. 4. By the increase of potassium and sulfur powder application, the soil pH at two different stages were almost not differential and the content of K, $P_2O$ and $SO_4$ in soil and $SO_4/P_2O_5$ ratio were increasing tendency.

• Journal of the Korean Society for Heat Treatment
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• v.28 no.2
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• pp.75-81
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• 2015

Effects of B and Cu additions on the microstructure and mechanical properties of high-strength bainitic steels were investigated in this study. Six kinds of high-strength bainitic steels with different B and Cu contents were fabricated by thermo-mechanical control process composed of controlled rolling and accelerated cooling. The microstructures of the steels were analyzed using optical and transmission microscopy, and the tensile and impact tests were conducted on them in order to investigate the correlation of microstructure with mechanical properties. Depending on the addition of B and Cu, various low-temperature transformation products such as GB (granular bainite), DUB (degenerated upper bainite), LB (lower bainite), and LM (lath martensite) were formed in the steels. The addition of B and Cu increased the yield and tensile strengths because of improved hardenability and solid solution strengthening, but decreased the ductility and low-temperature toughness. The steels containing both B and Cu had a very high strength above 1.0 GPa, but showed a worse low-temperature toughness of higher DBTT (ductile-to-brittle transition temperature) and lower absorbed energy. On the other hand, the steels having GB and DUB showed a good combination of tensile and impact properties in terms of strength, ductility, yield ratio, absorbed energy, and DBTT.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.1
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• pp.65-72
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• 2011

Twenty-four Holstein dairy cows were used to evaluate the single and combined effects of different levels of crude protein (CP) and monensin treatment during early lactation on blood metabolites, milk yield and digestion of dairy cows. The experiment was designed as a completely randomized block with a $3{\times}2$ factorial arrangement of treatments. The factors were three concentrations of CP supplement (19.5, 21.4, and 23.4% of dry matter) and two levels of monensin (0 and 350 mg per cow per day). The experiment consisted of three phases and each phase was 3 wk in length. Monensin did not affect milk yield, lactose, solids-non-fat (SNF), blood glucose, triglyceride and DMI, but increased blood cholesterol, blood urea nitrogen (BUN), insulin and reduced blood ${\beta}$-hydroxybutyrate (BHBA), milk fat and protein percentage. Monensin premix significantly decreased rumen ammonia, but rumen pH and microbial protein synthesis were not affected by monensin treatment. Increasing dietary CP improved milk and protein production, but did not alter the other components of milk. Digestibility of NDF, ADF, CP were improved by increasing dietary CP. Increasing dietary CP from 19.5 to 21.4% had no significant effect on ruminal ammonia, but increasing CP to 23.4% significantly increased ruminal ammonia. There was a linear relationship between level of crude protein in the diet and volume of urine excretion. Microbial protein synthesis was affected by increasing CP level; in this way maximum protein synthesis was achieved at 23.4% CP.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.365-368
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• 2008

In recent, the crushed sand as a fine aggregate has increasingly used for concrete industry due to the shortage of natural sand from river and the growing demand for protection of natural environments. Aggregates may have a significant influence on the properties of self-compacting concrete (SCC) including self-compacting mortar (SCM). The rheological properties of SCC and SCM using crushed sand as a fine aggregate has been compared to that of SCC and SCM using natural sand and mixed sand of both. Test results indicate that the yield stress of SCM containing 50% of mixed sand present higher than those prepared with natural sand and crushed sand according to SP content. the slump values of SCC with natural sand have approximately 5-15% higher than those of SCC with crushed sand. Also the L-box test values ($H_2/H_1$) of SCC with natural sand have approximately 20-30 higher than those of SCC with crushed sand under same water/cement ratio and viscosity enhancing admixture.