• Composites Research
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• 제26권4호
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• pp.213-217
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• 2013

The focus in the present work is to study the agro-waste corn husk bio-filler as reinforcement for polypropylene. These materials have been created by extrusion and injection molding. The effect of filler content by 10, 20, 30 and 40 wt. % and mesh sizes of 50~100, 100 and 300 on the mechanical properties was studied. For the un-notched specimens, the results of flexural strength showed a declining trend with increase the filler loading and the results of impact strength showed an increasing trend with increase the mesh size. In contrast, enhanced flexural modulus was observed with increasing filler loading and size.

• 한국포장학회지
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• 제28권2호
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• pp.97-104
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• 2022

본 연구에서는 식량자산인 바이오매스 옥수수의 부산물인 옥수수 피를 LLDPE에 첨가하여 바이오베이스 시트를 제조할 때 물성개선을 위한 상용화 혼합물의 적정 첨가량을 찾고자 한다. 옥수수 피의 상용성을 높이고자 ESO와 실란 혼합물 실란을 농도별로 첨가하여 비표면적, 함수율, 입도분석 및 제조한 바이오베이스 플라스틱 시트의 물성변화를 조사하였다. 비표면적은 1.105 m²/g, 입도는 19 ㎛에서 가장 우수하였다. 시트의 충격강도, 인장강도, 신율 및 경도는 대조구에 비해 SI-1-CR은 높게 나타났으나 SI-2-CR과 SI-3-CR은 낮게 나타났다. 또 실란 혼합물 1% 처리구에서 가장 높게 나타났다. 굴곡강도와 탄성율은 첨가량이 증가할수록 높게 나타났다. 생산 성도 대조구에 비해 큰 차이가 없었으며, 원가의 경우도 바이오매스 부산물로 대조구 석유계 합성 플라스틱 수지보다 50%이상 저렴하여 경제성이 있다고 사료되었다. 이제품은 수퍼, 마트 등의 1회용 봉투, 종량제 봉투 등에 사용될 수 있을 것이다. 이상의 결과로부터 실란 혼합물 1%를 첨가하여 바이오베이스 플라스틱 시트를 제조하는 것이 바람직할 것으로 사료되었다.

• 한국초지조사료학회지
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• 제34권4호
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• pp.288-295
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• 2014

본 연구는 옥수수 사일리지를 이용하여 TMR 제조 시 배합시간에 따른 물리적 특성(Particle size, peNDF 및 laceration)의 변화를 조사하고, 반추위 내 in situ 건물분해율 및 비유중기 착유우의 유생산성에 미치는 영향을 조사하고자 수행되었다. TMR 시험사료는 동일한 원료를 이용하여 배합시간을 30분(T1구)과 50분(T2구)으로 제조하였다. Penn State Particle Size Separator (PSPS, 19 mm와 8mm 체)로 분리하여 입자크기의 분포를 분석한 결과 배합 시간이 30분(T1)에서 50분(T2)로 증가함에 따라 하층(<8mm)의 비율이 유의적으로 증가하였고(p<0.01), $peNDF_{&gt;8.0}$는 유의적으로 감소하였으며(p<0.01), 굵은 비율(${\geq}1mm$) 이 유의적으로 감소하였다(p<0.01). 반추위 내 in situ 건물 분해율은 모든 배양시간에서 처리구간 차이가 없었지만 24시간 배양에서 T1구에서 유의적으로 높게 나타났다. (p<0.01). 산유량은 처리구간 차이가 없었지만 유지방은 T1이 유의적으로 높게 나타났다(p<0.01). 본 연구 결과에서 옥수수 사일리지 위주의 TMR 제조 시 배합시간을 단축 조절함으로서 산유량 및 유성분에 대한 부정적 영향 없이 조사료의 물리적 사료가치를 증진하는데 효과가 있을 것으로 기대된다.

• 한국식품영양학회지
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• 제11권5호
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• pp.521-527
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• 1998

Removabilities of heavy metals(Cd and Pb) by the tea materials (barley-tea, corn-tea, jasmin-tea, brown rice-green tea, black-tea, cassia tora-tea, persimmon peel-tea, and rice-tea) in the tea-water were studied in the various conditions ; particle size of tea (20, 40, 70 mesh), concentration of heavy metal (25, 50, 100 ppm) and extraction temperature(20, 30, 50, 100$^{\circ}C$). The removabilities by the tea solids were increased as the particle size decreased, concentration of heavy metal increased, and extracting temperature increased. Of the nine kinds of tea, Cd and Pb removability by jasmin-tea was highest. In addition, heavy metal removability by cassia tora tea was better than that of other tea as extraction temperature was increased.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.759-761
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• 1992

$0.10Pb(Sb_{1/2}Sn_{1/2})O_3-0.25PbTiO_3-0.65PbZrO_3+MnO_2(0.18mol%)$, NiO(0.15mol%) temary compound ceramics won fabricated by the mixed-oxide method. Noise properties of the pyroelectric infrared sensor were investigated with particle size of the raw materials and gain size of the specimens. Particle size were decreased and sintered density, voltage resposivity were increased with increasing the ball-mill times. The specimen ball-milled for a 80[hr] showed a good pop-corn noise properties.

• 한국초지조사료학회지
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• 제11권1호
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• pp.43-52
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• 1991

The overall objective of this research was to evaluate the effects of spraying sulfuric acid solution, and adding corn meal or molasses to reed canarygrass silage on digestibility of dry matter (DM) and fibrous components in ruminant. DM content of molasses or corn meal treated silages were higher than control. Whereas, sulfuric acid treated silage showed lower DM content compared with untreated control. Acid detergent fiber content was similar among treatments, but neutral detergent fiber (NDF) and hemicellulose concentration were higher in treated silages than those of control. Organic acids content were also increased in treated silages. In contrast, silage pH were lower in treated silages. Treated silages increased both rate and extent of DM and NDF in situ digestibility compared to control at all incubation times. Especially, 7 % molasses and 0.4 % sulfuric acid treated silages increased DM and NDF digestibility significantly after 12 hours of incubation compared with control. In nitro DM and NDF digestibility showed similar trend to in situ incubation. Also treated silages(mo1asses or sulfuric acid treated) incubated in situ had higher particle-associated carboxymethylcellulase activity throughout the incubation except 72 hours.

• Asian-Australasian Journal of Animal Sciences
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• 제30권4호
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• pp.554-561
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• 2017

Objective: This experiment was conducted as a $3{\times}2{\times}2$ factorial design to examine the effects of particle size (mean particle size of 331, 640, or $862{\mu}m$), evaluation method (direct vs indirect method) and adaptation duration (7 or 26 days) on the energy content and the apparent total tract digestibility (ATTD) of various chemical components in wheat when fed to finishing pigs. Methods: Forty-two barrows ($Duroc{\times}Landrace{\times}Yorkshire$) with an initial body weight of $63.0{\pm}0.8kg$ were individually placed in metabolic cages and randomly allotted to 1 of 7 diets with 6 pigs fed each diet. For the indirect method, the pigs were fed either a corn-soybean meal based basal diet or diets in which 38.94% of the basal diet was substituted by wheat of the different particle sizes. In the direct method, the diets contained 97.34% wheat with the different particle sizes. For both the direct and indirect methods, the pigs were adapted to their diets for either 7 or 26 days. Results: A reduction in particle size linearly increased the digestible energy (DE) and metabolizable energy (ME) contents as well as the ATTD of gross energy, crude protein, organic matter, ether extract (EE) and acid detergent fiber (ADF) (p<0.05), and had a trend to increase the ATTD of dry matter of wheat (p = 0.084). The DE, ME contents, and ATTD of gross energy, crude protein, dry matter and organic matter were higher (p<0.05) when determined by the direct method, but the ATTD of ADF, EE, and neutral detergent fiber were higher when determined by the indirect method (p<0.05). Prolongation of the adaption duration decreased the ATTD of neutral detergent fiber (p<0.05) and had a trend to increase the ATTD of EE (p = 0.061). There were no interactions between particle size and the duration of the adaptation duration. The ATTD of EE in wheat was influenced by a trend of interaction between method and adaptation duration (p = 0.074). The ATTD of ADF and EE in wheat was influenced by an interaction between evaluation method and wheat particle size such that there were linear equations (p<0.01) about ATTD of ADF and EE when determined by the direct method but quadratic equations (p = 0.073 and p = 0.088, respectively) about ATTD of ADF and EE when determined by the indirect method. Conclusion: Decreasing particle size can improve the DE and ME contents of wheat; both of the direct and indirect methods of evaluation are suitable for evaluating the DE and ME contents of wheat with different particle sizes; and an adaptation duration of 7 d is sufficient to evaluate DE and ME contents of wheat in finishing pigs.

• Applied Biological Chemistry
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• 제47권1호
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• pp.72-77
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• 2004

5% corn oil과 17 mM Brji 700으로 제조한 oil-in-water emulsion(O/W)에서 과량의 잉여 surfactant가 phenol이 첨가된 O/W의 산화에 미치는 영향을 알아보기 위하여 Brji 700을 $0{\sim}2%$의 농도로 O/W에 첨가한 경우, 첨가된 surfactant의 양이 증가할수록 droplet의 particle size는 커지는 경향을 나타내었다. 또한 continuous phase의 surfactant 농도도 높아지며 phenol 함량도 상대적으로 높아지는 것을 알 수 있었다. Phenol류가 100 ppm의 농도로 첨가된 O/W에 과량의 surfactant$(0{\sim}2%)$를 첨가하고 30일간 저장 기간별 hydroperoxide의 생성량을 측정한 결과, 대조구에 비해 낮은 hydroperoxide 함량을 보여 surfactant를 첨가하지 않은 실험구와 유사한 경향을 보였으나, hydroperoxide 함량은 surfactant를 추가하지 않은 실험구 보다 더 낮은 값을 나타내었다. 또한 phenol 종류 및 surfactant 농도별 hydroperoxide 생성억제 효과와 headspace aldehyde 생성 억제 효과는 BHT>procyanidin B3-3-O-gallate>(+)-gallocatechin>(+)-catechin 및 2%>1%>0% surfactant 첨가의 순서로 나타났다. 이러한 결과는 phenol성 물질과 과량의 surfactant micelle에 의해 emulsion으로부터 continuous phase로 hydroperoxide의 physical location 변화가 발생하는 것을 나타낸다.

• 한국농공학회지
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• 제31권1호
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• pp.82-95
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• 1989

This study was carried out for the stability analysis of earth dam by the variation of compaction density. The test samples were taken from five kinds of soil used for banking material and the degree of compaction for this samples were chosen 100, 95, 90, 85, and 80 percent. The stability problems were analysed by the settlement and camber( extra banking) of dam, strength parameter and dam slope, and coefficient of permeability and seapage flow through dam body. The results of the stability analysis of earth dam are as follows. 1. The more the fine particle increases and lower the compaction degree becomes, the lower the preconsolidation load becomes but the compression index becomes higher. 2. Sixty to eighty percent of settlement of dam occurs during the construction period and the settlement ratio after completion of dam is inversly proportional to the degree of compaction. 3. The camber of dam has heigher value in condition that it has more fine particle(N) and heigher dam height(H) with the relation of H= e(aN-bH-e). 4. The cohesion(C) decreases in proportion to compaction degree(D) and fine particle(N) with the relation of C= aD+ bN-c, but the internal friction angle is almost constant regardless of change of degree of compaction. 5. In fine soil, strength parameter from triaxial compression test is smaller than that from direct shear test but, they are almost same in coarse soil regardless of the test method. 6. The safety factor of the dam slope generally decreases in proportion to cohesion and degree of compaction but, in case of coarse soil, it is less related to the degree of compaction and is mainly afected by internal friction angle. 7. Soil permeability(K) decreases by the increases of the degree of compaction and fine particle with relation of K=e(a-bl)-cN) 8. The more compaction thickness is, the less vertical permeability (Kv) is but the more h6rzontal permeability (KH) is, and ratio of Kv versus KH is largest in range from 85 to 90 percent of degree of corn paction. 9. With the compaction more than 85 percent and coefficient of permeability less than ${\alpha}$X 10-$^3$cm/sec, the earth dam is generally safe from the piping action.

• Journal of Pharmaceutical Investigation
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• 제14권3호
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• pp.122-130
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• 1984

The dissolution profiles of the seven branded prednisolone tablets were determined by means of available compendium. Those tablets were stored at $40^{\circ}C,\;50^{\circ}C\;and\;60^{\circ}C$ for 15, 30 and 60 days respectively. Under the stress conditions, the dissolution efficiency showed significant changes. It is considered that the determination of shelf life of drug from these aging effects is possible because the dissolution data followed a logarithmic distribution. There were no substantial differences of dissolution between two prednisolone formulations with different particle size not larger than $100\;{\mu}m$. The effect of two starches (corn and potato) on the rate of dissolution of prednisolone from dosage form was also investigated. All marketed tablets met the requirement of the established compendium.