• KIEAE Journal
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• v.16 no.3
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• pp.83-88
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• 2016

Purpose : This study aimed to verify the surface hardness and water repellency of earth paint manufactured with earth, a natural material, and provide the results as basic data for paint made with natural materials. Method : After presenting the accurate manufacturing methods for basic materials for paint, the authors conducted and analyzed experiments to evaluate surface hardness and water repellency, fundamental performance indicators for paint, based on different mixture ratios. From the results of the experiment to assess the surface hardness of flour-based earth paint, we observed high surface hardness only after painting the specimen three times. Since potato starch-based earth paint has higher viscosity than its flour-based counterpart, the former did not paint well on the first occasion, resulting in low surface hardness. After painting two or more times, however, it was observed to have higher surface hardness than flour-based earth paint. Result : It was found that at least three iterations of painting was required to obtain high surface hardness of potato starch-based earth paint. Furthermore, the results of the water resistance experiment of earth paint suggest that the use of environment-friendly finishing materials coupled with boiled linseed oil will mitigate the drawbacks of earth paint. The experiment with one-year-old specimens also demonstrated similar water repellent characteristics, which indicates that the performance will improve once the paint has dried for a sufficient period of time.

• KSBB Journal
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• v.30 no.3
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• pp.109-113
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• 2015

Current drying and encapsulation methods for probiotics manufacturing are complicate and cost-burdened processes. The aim of this study was to develop a simple ingredient mixture to make probiotic granules via one-step process, providing not only a cryoprotective effect during freezing and drying but also high survival ratio in gastrointestinal tract. As cryoprotectans, commercially available ingredients including skim milk, monosaccharide (trehalose or glycerin), maltodextrins (with low or high degree of equivalents) were used. Their cryoprotective effect during lyophilization and survival ratios in artificial gastric juice and bile salt were measured against 3 strains of lactic acid bacteria (LAB) (Lactobacillus plantarum, Lb. brevis, and Lactococcus lactis). As results, 3 mixtures with different compositions showed a cryprotective effect on LAB tested and the best compostion was dependant upon LAB; skim milk 10%, trehalose 15%, glycerin 0.5%, and NaCl 1% was for Lb. plantarum and Lc. lactis, and maltodextrin 10% instead of skim milk was for Lb. brevis. In addition, those mixtures showed similar survival effect on LAB tested. These results demonstrate that skim milk or maltodextrins with trehalose, glycerin, and NACl can be effectively used for onestep lyophilization of LAB as an alternative method of encapsulation.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.6
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• pp.816-824
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• 2005

The effects of the nonionic surfactant Tween 80 and a mixture of fibrolytic enzymes on total tract digestion, in situ disappearance (ISD) and ruminal fermentation characteristics of orchardgrass hay and barley grain were investigated in a 4${\times}$4 Latin square experiment with 4 non-lactating Holstein cows and 4 diets in 4 periods. Cows were offered a total mixed ration of 50% rolled barley grain and 50% orchardgrass hay treated with either 1) water (control), 2) 0.2% (vol/wt) Tween 80, 3) 0.2% (vol/wt) hydrolytic enzyme, or 4) 0.2% hydrolytic enzyme plus 0.2% Tween 80. Total tract digestibility coefficients of DM, nitrogen, NDF and ADF were not affected (p>0.05) by dietary treatment. Compared to the control, the rate of ISD of DM from orchardgrass hay was faster (p<0.05) in cows receiving diets treated with the enzyme alone or with enzyme plus Tween 80 (0.06/h vs. 0.076 and 0.069/h). The rate of digestion was lower (p<0.05) as compared to control when barley grain was treated with these additives. Ruminal fluid pH and concentrations of total VFA, acetate, isobutyrate and butyrate were not affected (p>0.05) by treatments. Cows that consumed diets treated with enzyme plus Tween 80 had higher (p<0.05) ruminal concentrations of propionate and isovalerate, and lower (p<0.05) acetate:propionate ratios. Compared to the control, microbial protein synthesis tended (p = 0.13) to increase with the addition of enzyme to the diet while nonammonia nitrogen flow to the duodenum increased (p<0.05) with both enzyme and Tween 80 treatments. The study indicated that fibrolytic enzymes alone or in combination with Tween 80 could enhance ISD of orchardgrass hay and ruminal concentrations of propionate, valerate and iso-valerate, but do not affect total tract digestibility.

• Korean Journal of Agricultural Science
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• v.47 no.1
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• pp.11-18
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• 2020

Eggs are likely to be used in agriculture because they can provide enough nutrients for crop growth. Statistics show that a large number of eggs are lost due to breakage before reaching the final consumer. The purpose of this study was to make a natural liquid fertilizer as a substitute for chemical fertilizers using broken eggs as a resource and to evaluate the efficiency of the formulated fertilizer. To make the liquid fertilizer, the broken eggs and distilled water were mixed at ratios of 6 : 4 and 4 : 6. Then, effective micro-organisms (EM) and sugar were added, and the mixture was fermented. The temperature and electrical conductivity (EC) increased gradually with the fermentation while the pH decreased. When evaluated following the seed germination index method of the compost, it was found that the fertilizer matured 10 days after the beginning of the experiment. The growth experiment was conducted with lettuce in which the fermented liquid fertilizer was compared with a commercial liquid fertilizer. The 6 : 4 treatment produced plants with the densest fresh shoot and roots weighing 41.6 and 4.6 g, respectively. The number of leaves (12.3 per plant) was also the highest for the 6 : 4 treatment. Soil analysis showed that the soil pH was improved, and the soil organic matter was increased in the fermented liquid fertilizer treatment.

• Economic and Environmental Geology
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• v.30 no.1
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• pp.1-14
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• 1997

The shales from the Euiseong area are interbedded along the bedding in Cretaceous Gyeongsang Supergroup, which are composed mainly of quartz, plagioclase, K-feldspar and associated with trace amount of biotite, muscovite, chlorite, pyrite, hematite, carbonate and clay minerals. The ratio of $Al_2O_3/Na_2O$ and $K_2O/Na_2O$ in shales from the Shindong Group are ranged from 9.16 to 24.32 and from 1.70 to 5.97, and the Hayang Group ranged from 2.76 to 8.89 and from 0.42 to 2.74, which are negative correlated between $K_2O/Na_2O$ and $Al_2O_3/Na_2O$ against $SiO_2/Al_2O_3$ respectively. Those are suggested that controlled of mineral compositions in shales due to substitution and migration of elements by sedimentation and diagenesis. These shale formation were deposited in basin of terrestrial environments originated from the igneous rocks, and the REE of these rocks are not influenced with diagenesis and hydrothermal alterations on the basis of $Al_2O_3$ versus La, La against Ce, Zr versus Yb, the ratios of La/Ce (0.43 to 0.62) and Th/U (1.11 to 10.71). The narrow range in trace and REE element characteristics as Co/Th (0.63 to 1.92), La/Sc (1.98 to 5.90), Sc/Th (0.58 to 1.30), V/Ni (0.90 to 3.25), Cr/V (0.45 to 1.78), Ni/Co (1.88 to 6.67) and Zr/Hf (30.04~60.87) of these shales argues for inefficient mixing of the simple source lithologies during sedimentation. These rocks also show much variation in $La_N/Yb_N$ (6.90 to 17.02), Th/Yb (4.17 to 13.68) and La/Th (1.98 to 5.90), and their origin is explained by derivation from a mixture of intermediate to acidic igneous rocks.

• Journal of Power System Engineering
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• v.12 no.4
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• pp.5-11
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• 2008

The RI gasoline engine haying a sub-chamber had a high cycle variation due to the difficulty of the residual gas scavenge in the sub-chamber. To solve this problem and improve the combustion performance of RI engine, we devised a method to inject directly CNG fuel into the sub-chamber. A DI diesel engine of single cylinder was converted into a RI-CNG engine and an electronic control unit for the engine was manufactured. In this study, the combustion characteristics of the RI-CNG engine were investigated with the injection timings and air excess ratios at the load conditions of 50% throttle open rate and 1700rpm. As the results from this study, the RI-CNG engine worked reliably under the condition of the ignitable lean limit of $\lambda=1.7$ by showing the $COV_{imep}$ below about 5%. And the highest thermal efficiency could be obtained in the injection timing that produced the high imep and the low $COV_{imep}$ at the same time. The CO emission concentration indicated very low values and the THC and $NO_x$ showed an opposite pattern. With a view to improving the thermal efficiency and reducing the harmful emissions, the proper control region of the ignition timing and the mixture ratio were nearly ATDC $20^{\circ}\sim50^{\circ}$ and $\lambda=1.4$ respectively.

• Structural Engineering and Mechanics
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• v.64 no.3
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• pp.361-379
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• 2017

In this article, the vibration behavior of double-bonded sandwich microplates with homogeneous core and nanocomposite facesheets reinforced by carbon nanotube and boron nitride nanotube under multi physical fields such as 2D magnetic and electric fields is investigated. Symmetric and un-symmetric distributions of nanotubes are considered for facesheets of sandwich microplates such as uniform distribution and various functionally graded distributions. The double-bonded sandwich microplates rest on visco-Pasternak foundation. Material properties of sandwich microplates are obtained by the extended rule of mixture. The sinusoidal shear deformation theory (SSDT) is employed to describe displacement fields of sandwich microplates. Also, the dimensionless natural frequency is obtained by classical plate theory (CPT) and compared with the obtained results by SSDT. It can be seen that the obtained dimensionless natural frequencies by CPT are higher than SSDT. In order to study the material length scale parameters, modified strain gradient theory at micro scale is utilized and then, the equations of motion are derived using Hamilton's principle. The effects of different parameters such as foundation parameters including Winkler, shear layer and damping coefficients, various distributions and volume fraction of nanotubes, core to facesheet thickness ratio, aspect and side ratios on the dimensionless natural frequencies are discussed in details. The results of present work can be used to optimum design and control of similar systems such as micro-electro-mechanical and nano-electro-mechanical devices.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.5
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• pp.633-637
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• 2004

The experiment of silage for preservation of fresh Italian ryegrass (Lolium multiflorum) was carried out to examine whether the fermentation quality and microbial degradation in the rumen can be altered by the treatment of amino acids fermentation byproduct (AFB). The plant was ensiled for 40 days with 4 treatments of different ratios of AFB and sugarcane molasses (SCM) mixture. The treatment 2 (T2, AFB:SCM=100:0) and treatment 3 (T3, AFB:SCM=40:60) silages showed higher (p<0.05) concentrations of lactic acids, lower (p<0.05) pH and dry matter (DM) losses than the Control (T1, none additive) and treatment (T4, AFB:SCM=0:100) silages. The treatments 2 and 3 contained higher (p<0.05) DM and crude protein contents in silages compared to treatments 1 and 4 silages. The NDF, ADF and cellulose contents were also lower (p<0.05) in T2, T3 and T4 silages than T1 silage and fresh material before ensiled. The in situ rumen DM, NDF, ADF, hemicellulose and cellulose degradability was also higher (p<0.05) in T2, T3 and T4 silages than T1 silage, while the highest improvement was achieved with addition of AFB:SCM at level of 40:60 at ensiling. The result in this study indicates that the addition of AFB and SCM additives improved the silage fermentation and cell wall degradability of Italian ryegrass silage.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.431-437
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• 2006

This work was undertaken to study the effect of dietary fat source on the fatty acid profile of pork, and to evaluate the effect of inclusion of vitamin E in pig diets on lipid oxidation of pork tissue and processed pork products. Fifty-six pigs were allocated to four treatments, that included two dietary fat sources and two levels of vitamin E inclusion. Dietary fat was derived from either tallow, a source of saturated fatty acids (SFA), or from a mixture of soybean and linseed oils, which contain polyunsaturated fatty acids (PUFA). Vitamin E was included at either 0% or 0.011% of the diet. Growth and carcass characteristics were not affected by the dietary treatments. Dietary fat source affected the fatty acid profile of the longissimus muscle and subcutaneous fat tissue, with the PUFA diet resulting in significantly more polyunsaturated fatty acids in the tissues, and more favourable ratios of SFA to PUFA and C18:2 to C18:3 in terms of human health considerations. Lipid oxidation was significantly greater in tissues and processed products from PUFA-fed pigs. Inclusion of vitamin E in the diets, however, reduced the extent of lipid oxidation in the meat and meat products. Dietary manipulation of the fatty acid profile of pigs is an effective means of altering the fat composition of pork in order to provide human consumers with a healthy product. Vitamin E is effective as an antioxidant agent, particularly where processed products are concerned.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.1
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• pp.63-67
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• 1992

This paper reports the effects of rare earth nitrate (REN) on the growth of internal organs and mineral elements in serums of broiler chickens. The REN used is mixture of light RE containing mainly La, Ce, Pr and Nd 4 elements. 40 eight-week old AA broiler chickens were divided randomly into four groups that their treatments were respectively 0, 20, 200 and 2000 mg REN/kg feed and the duration of the experiment was 60 days. Responses were measured in terms of internal organic weight and tissue, contents of mineral elements in serums. There were no significant differences between the organ ratios and tissue changes of the 20, 200 mg REN/kg groups and the control group. The organs included the heart, liver, kidneys, lungs, testicles, thyroids, adrenal glands, pancreas, tonsies of caecum, stomachus glandularis, duodenum, ileum and bursa of Fabricius. The liver and thyroid indices of 2000 mg REN/kg group were significantly higher than those of the control group (p < 0.01, p < 0.05) and the adrenal gland index lower (p < 0.05). The pathlolgic changes in the heart, kidney and thyroid were more serious than that of the control group. No significant differences occurred between the contents of K, Na, Mg elements in the serum of all groups, with the exception of the content of Ca, which was higher in the 2000 mg/kg group (p < 0.05). The contents of all trace elements including Mn, Zn and Cu, but except Fe, in the serums of all the treated groups were significantly higher than those of the control group (p < 0.01).