• Composites Research
• /
• v.30 no.4
• /
• pp.241-246
• /
• 2017

The brittle nature in most FRP composites is accompanying other forms of energy absorption mechanisms such as fibre-matrix interface debonding and ply delamination. It could play an important role on the energy absorption capability of composite structures. To solve the brittle nature, the adhesion between pines and composites was studied. Thermal treated pines were attached on carbon fiber reinforced polymer (CFRP) by epoxy adhesives. To find the optimum condition of thermal treatment for pine, two different thermal treatments at 160 and $200^{\circ}C$ were compared to the neat case. To evaluate mechanical and interfacial properties of pines and pine/CFRP composites, tensile, lap shear and Izod test were carried out. The bonding force of pine grains was measured by tensile test at transverse direction and the elastic wave from fracture of pines was analyzed. The mechanical, interfacial properties and bonding force at $160^{\circ}C$ treated pine were highest due to the reinforced effect of pine. However, excessive thermal treatment resulted in the degradation of hemicellulose and leads to the deterioration in mechanical and interfacial properties.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.30 no.10A
• /
• pp.912-921
• /
• 2005

Optical burst switching(OBS) is a promising solution for building terabit optical routers and realizing If over WDM. Channel scheduling Algorithm for reduce contention is one of the major challenges in OBS. We address the issue of how to provide basic burst channel scheduling in optical burst switched WDM networks with fiber delay lines(FDLs). In OBS networks the control and payload components or a burst are sent separately with a time gap. If CHP arrives to burst switch node, because using scheduling algorithm for data burst, reservation resources such as wavelength and transmit data burst without O/E/O conversion, because contention and void between burst are happened at channel scheduling process for data burst that happened the link utilization and bust drop probability Existent proposed methods are become much research to solve these problems. Propose channel scheduling algorithm that use Release Time of bust to emphasize clearance between data and data dissipation that is happened in data assignment in this treatise and maximize bust drop probability and the resources use rate (RTUC : Release Time Unscheduled Channel). As simulation results, Confirmed that is more superior in terms of data drop and link utilization than scheduling algorithm that is proposed existing. As simulation results, confirmed improved performance than scheduling algorithm that is proposed existing in terms of survival of burst, efficiency resource and delay. However, In case load were less, degradation confirmed than existent scheduling algorithm relatively, and confirmed that is superior in data drop aspect in case of load increased.

• Asian-Australasian Journal of Animal Sciences
• /
• v.24 no.8
• /
• pp.1092-1099
• /
• 2011

To evaluate the effects of replacing concentrate with urea molasses treated fermented wheat straw (FWS) ensiled with cattle manure (CM) on ruminal characteristics, in situ digestion kinetics and nitrogen (N) metabolism was studied in Nili Ravi cannulated buffalo bulls in a $4{\times}4$ Latin Square Design. Wheat straw treated with urea (4%) and molasses (6%) was ensiled with cattle manure (CM) (70:30) and fermented for 40 days. Four iso-nitrogenous and iso-caloric diets were formulated. In the FWS0, FWS10, FWS20 and FWS30 diets 0, 10, 20 and 30% of the concentrate was replaced with FWS, respectively. Daily intake by bulls was restricted to 1.5% dry matter (DM) of body weight. Ruminal ammonia nitrogen concentration was greater (p<0.05) in bulls fed FWS diet than for those fed FWS0 diet at 3, 6, 9 and 12 h post-parandial. Bulls fed FWS 20 and FWS 30 diets had higher ruminal pH at 3 and 6 h post-parandial than bulls fed FWS10 and FWS0. Ruminal total volatile fatty acid (VFA) concentrations 3 h post-parandial were greater (p<0.05) in bulls fed FWS0 than those fed FWS diets. However ruminal VFA tended to increase at 6, 9 and 12 h post-parandial as the level of FWS increased. In situ ruminal DM and neutral detergent fiber (NDF) degradation, rates of disappearance and extent of digestion were higher (p<0.05) for bulls fed FWS30 diet than those fed FWS0. Ruminal DM and NDF lag time tended to decrease (p<0.05) as FWS concentration in the diet increased. Feed intake, nitrogen intake, N-balance and blood urea-N did not differ (p>0.05) in buffalo bulls fed different diets. Wheat straw treated with urea and molasses and ensiled with CM enhanced the nutritive value of wheat straw and improved nutrient utilization in buffalo bulls when up to 30% of the concentrate was replaced with FWS; no adverse effects on ruminal characteristics and nutrients digestibilities were detected.

• Asian-Australasian Journal of Animal Sciences
• /
• v.29 no.12
• /
• pp.1725-1733
• /
• 2016

Recent findings have shown that microbial nitrogen flow and digestible energy of diets are increased when urea is combined with a slow-release urea (SRU) in diets with a starch to acid detergent fibre ratio (S:F) 4:1. This affect is attributable to enhanced synchrony between ruminal N availability for microbial growth and carbohydrate degradation. To verify the magnitude of this effects on lamb performance, an experiment was conducted to evaluate the effects of combining urea and a SRU in diets containing S:F ratios of 3:1, 4:1, or 5:1 on performance, dietary energetics and carcass characteristics of finishing lambs. For that, 40 Pelibuey${\times}$Katahdin lambs ($36.65{\pm}3kg$) were assigned to one of five weight groupings in 20 pens (5 repetition/treatments). The S:F ratio in the diet was manipulated by partially replacing the corn grain and dried distiller's grain with solubles by forage (wheat straw) and soybean meal to reach S:F ratios of 3:1, 4:1 or 5:1. An additional treatment of 4:1 S:F ratio with 0.8% urea as the sole source of non-protein nitrogen was used as a reference for comparing the effect of urea combination vs. conventional urea at the same S:F ratio. There were no treatment effects on dry matter intake (DMI). Compared the urea combination vs urea at the same S:F ratio, urea combination increased (p<0.01) average daily gain (ADG, 18.3%), gain for feed (G:F, 9.5%), and apparent energy retention per unit DMI (8.2%). Irrespective of the S:F ratio, the urea combination improved the observed-to-expected dietary ratio and apparent retention per unit DMI was maximal (quadratic effect, $p{\leq}0.03$) at an S:F ratio of 4:1, while the conventional urea treatment did not modify the observed-to-expected net energy ratio nor the apparent retention per unit DMI at 4:1 S:F ratio. Urea combination group tended (3.8%, p = 0.08) to have heavier carcasses with no effects on the rest of carcass characteristics. As S:F ratio increased, ADG, G:F, dietary net energy, carcass weight, dressing percentage and longissimus thoracis (LM) area increased linearly ($p{\leq}0.02$). Combining urea and a slow-release urea product results in positive effects on growth performance and dietary energetics, but the best responses are apparently observed when there is a certain proportion (S:F ratio = 4:1) of starch to acid detergent fibre in the diet.

• Journal of Mushroom
• /
• v.11 no.4
• /
• pp.208-213
• /
• 2013

The contents of raw materials which are components of mixed substrate for mushroom cultivation were analyzed to optimize the composition. The pure protein(amino acid) level of soybean meal was the highest, 44.02% followed by those of soybean curd residue(31.5%) and cotton seeds meal(30.6%). The non protein nitrogen(NPN) contents in crude protein of main nitrogen materials were 2.4% for soybean meal and 5.6% for dried soybean curd residue, while those of wheat bran and rice bran used as the carbon source were relatively higher, 17.6% compared to that of nitrogen supplying media. Crude protein content per price was 6.0 for rapeseed meal, indicating that it is high crude protein content per price. Nitrogen-free extract(NFE) considering as an ingredient for mycelial growth were high in alphacorn(72.9%) and wheat bran B(57.2%). Acid detergent fiber(ADF) was high in corncob, 51.88%, its use for cultivation of brown rot fungi including Lentinus lepideus should pay attention because the fungi lack complete lignin degradation activity.

• Applied Chemistry for Engineering
• /
• v.18 no.6
• /
• pp.557-561
• /
• 2007

Polypropylene (PP)/corn starch master batch (starch-MB) blends with different PP compositions of 40, 50, 60, and 80 wt% were prepared by melt compounding at $200^{\circ}C$, using lab scale Brabender mixer. The chemical structures and thermal properties of the PP/starch-MB blends were investigated by FT-IR, differential scanning calorimetry (DSC), and thermogravimetric analyzer (TGA). The chemical structure was confirmed by the existence of hydroxy group. There was no district change in melting temperature and melting enthalpy, and TGA curve indicated a decrease in degradation temperature with starch-MB content. The porosity change of blend was measured by scanning electron microscope (SEM), the degree of porosity on the blend surface increased with the starch-MB content. The rheological properties indicated an increase in complex viscosity, shear thinning tendency and elasticity with the starch-MB concentration. These effects were confirmed by an oscillatory viscometer at $200^{\circ}C$. From these results, it is found that 40 wt% is the optimum starch-MB concentration. The fiber was fabricated from PP60/MB40 with 40 wt% starch-MB and the porosity and tensile properties were investigated.

• Korean Journal of Food Science and Technology
• /
• v.28 no.1
• /
• pp.169-178
• /
• 1996

Target parameters such as water solubility index (WSI), intrinsic viscosity (IV), water holding capacity (WHC), oil holding capacity (OHC), soluble dietary fiber (SDF) and microstructure were investigated on three different screw configurations during twin-screw extrusion of wheat bran. WSI of raw wheat bran (RWB) was 13.7%, while that of extrudates ranged $16.3{\sim}23.2%$ when extruded using screw configurations with 5 reverse screw elements (RSE). It was found that the moisture content of RWB greatly affected WSI of extrudates. IV of wheat bran extrudates increased from 10.6 ml/g of RWB to $37.86{\sim}44.37\;ml/g$ of extrudates extruded using 3, 4 and 5 RSE, whose trend was highly related to the moisture content of RWB and the extrusion pressure. Multiplication of IV and soluble solid (SS) content exhibited good correlation $(R^2=0.85)$ with specific mechanical energy (SME). The results suggested that SS and molecular size are an important factor governed by the SME in solubilization of wheat bran. WHC increased with increasing feed rate and moisture content, while OHC decreased. SDF increased from 2.68% of RWB to $4.32{\sim}6.48%$ of extruded wheat bran, indicating the significant breakdown of cell wall components. Microstructure of the extrudates showed the distinct patterns of degradation and solubilization of cell wall structure, depending on the moisture content of RWB.

• Food Science and Preservation
• /
• v.16 no.4
• /
• pp.525-533
• /
• 2009

To explore cattail pollen powder as a functional food ingredient, we analyzed the general components of pollen powder, tested changes in the physical properties of dough containing the powder, and investigated the process ability of powder-containing dough in bread making by adding 3%, 6%, or 9% by weight of pollen powder to wheat flour. Cattail pollen powder consisted of (all w/w) 12.7-13.2% water, 15.7-17.8% crude protein, 1.3% crude fat, 7.5-7.7% free sugar, 14.7-18.6% crude fiber, 3.4-4.9% pollen, and 49.7-55.9% soluble nitrogen-free extract (NFE). Analysis of the physical properties of dough mixed with pollen powder showed that as more pollen powder was added, the absorption rate increased, but dough stability decreased. With increasing levels of cattail pollen powder, the falling number decreased, and amylase activity increased. Fermentability was highest in dough made with 3% by weight of pollen powder, and the bread product made from such dough had the greatest volume. As more cattail pollen powder was added, the moisture activity in dough tended to decrease to a greater extent than seen in control dough, and this tendency increased with time. We found that longer storage periods were associated with greater hardness and springiness, which indicated degradation in product quality. Therefore, it is suggested that bread products containing cattail pollen powder should be consumed within 3 days of preparation. In a taste survey, bread baked with 3% (w/w) cattail pollen powder scored highest in all questionnaire items.

• Journal of the Korean Geosynthetics Society
• /
• v.17 no.4
• /
• pp.169-177
• /
• 2018

Glass fiber reinforced polyester (GFRP) composites are widely used as structural materials in harsh environment such as underground pipes, tanks and boat hulls, which requires long-term water resistance. Especially, these materials might be damaged due to delamination between gelcoat and composites through an osmotic process when they are immersed in water. In this study, GFRP laminates were prepared by surface treatment of UPE (unsaturated polyester) gelcoat by vacuum infusion process to improve the durability of composite materials used in underground pipes. The composite surface coated with gelcoat was examined for surface defects, cracking, and hardness change characteristics in water-immersion environments (different temperatures of $60^{\circ}C$, $75^{\circ}C$, and $85^{\circ}C$). The penetration depth of cracks was investigated by micro CT imaging according to water immersion temperature. It was confirmed that cracks developed into the composites material at $75^{\circ}C$ and $85^{\circ}C$ causing loss of durability of the materials. The point at which the initial crack initiated was defined as the failure time and the life expectancy at $23^{\circ}C$ was measured using the Arrhenius equation. The results from this study is expected to be applied to reliability evaluation of various industrial fields where gelcoat is applied such as civil engineering, construction, and marine industry.

• Animal Bioscience
• /
• v.35 no.7
• /
• pp.999-1009
• /
• 2022

Objective: To improve the feeding value of rice straw (RS), this study evaluated the potential of rice straw fermented with Pleurotus sajor-caju (FRS) as dairy goat feed. Methods: Spent Pleurotus sajor-caju mushroom substrate was used as fungi inoculum to break the lignocellulose linkage of rice straw, which was solid-fermented at 25℃ to 30℃ for 8 weeks. The ruminal degradation of pangolagrass hay (PG), FRS, and RS were measured in situ for 96 hours in three dry Holstein cows, respectively. Effect of fungi fermented RS on milking performance was studied in feeding trials. A total of 21 Alpine goats a trial were divided into 3 groups: a control group in which PG accounted for 15% of the diet dry matter, and FRS or RS was used to replace the PG in the control group. Goats were fed twice a day under two 28-day trial in individual pens. Meanwhile, a 3×3 Latin square trial (14 days/period) was conducted to study the rumen digestion of three diets by using three fistulated dry goats. Rumen contents were collected for metabolite analyses every one to three hours on the last two days. Results: In situ study showed that fermentation could elevate the rumen degradable fraction and effective degradability of RS (p<0.05). Effective degradability of FRS dry matter was significantly increased from 29.5% of RS to 41.7%. Lactating trial results showed that dry matter intake and milk yield in the PG group and FRS group were similar and higher than those in RS group (p<0.05). The concentration of propionic acid and total volatile fatty acid in the RS group tended to be lower than those in PG group (p<0.10). There were no differences in rumen pH value and ammonia nitrogen level among the groups tested. Conclusion: Fermentation of rice straw by spent Pleurotus sajor-caju mushroom substrate could substantially enhance its feeding value to be equivalent to PG as an effective fiber source for dairy goat. The fermented rice straw is recommended to account for 15% in diet dry matter.