• Title/Summary/Keyword: Crack ratio

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Quality Characteristics of Cookies Prepared with Fresh and Steamed Garlic Powders (생마늘 및 증숙마늘 분말 첨가 쿠키의 품질특성)

  • Lee, Soo-Jung;Shin, Jung-Hye;Choi, Duck-Joo;Kwen, O-Chen
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.36 no.8
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    • pp.1048-1054
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    • 2007
  • The quality characteristics of cookies, prepared with the freeze dried fresh garlic (FGP) and steamed ($100^{\circ}C$, 20 min) garlic (SGP) powders, were investigated. The cookie samples in the present study were made by adding the garlic powders at different levels (0, 0.5, 1, 2, 4, and 6%). The highest spread ratio, $8.48{\pm}0.31$ and $8.62{\pm}0.21$, were obtained by mixing 6% FGP and 0.5% SGP with the cookies. Among the surface color of the cookies, the L-value decreased with increasing garlic powder contents compared to that of the control group, but the difference in the surface color among the kinds of garlic powders was insignificant. Although increases in the garlic powder content resulted in no noticeable difference among the a-value of the test group, the b-value was decreased significantly, particularly with increasing SGP contents. Hardness was also increased along with the garlic powder contents and was highest at its 2% content. When viewed from the sensor properties, the measured color tended to become brown at the garlic powder contents greater than 2%. The surface crack of the cookies also increased as the SGP content increased. Its garlic taste and flavor were slightly low at SGP added with 6% garlic powder content than FGP. The overall acceptability was higher in $0.5{\sim}4%$ added test samples than those in control group sample; it was highest for 1%, 2% and 0.5%, in decreasing order. In the sensor evaluation, the overall acceptability of the cookies was considerably different in the comparison of FGP added cookies with SGP added ones. Therefore, the optimal ratio investigated for making the garlic added cookies was shown to be 1 %, and its acceptability was relatively high for SGP added cookies.

The Physical and Thermal Properties Analysis of the VOC Free Composites Comprised of Epoxy Resin, and Dicyandiamide (VOC Free Epoxy Resin/Dicyandiamide 경화물의 배합비 변화에 따른 물리적 특성 및 열적특성 분석)

  • Kim, Daeyeon;Kim, Soonchoen;Park, Young IL;Kim, Young Chul;Lim, Choong-Sun
    • Clean Technology
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    • v.21 no.1
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    • pp.76-82
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    • 2015
  • Volatile organic compounds (VOC) free adhesives have been interested by many scientists and engineers due to environmental regulations and the safety of industrial workers. In this work, a series of composites composed with bisphenol A epoxy resin used as solvent, dicyandiamide, and promoter were prepared to investigate the most appropriate molar ratio for steel-steel adhesion. The cured test specimen of each composite were measured with universal testing machine (UTM) to figure out mechanical properties such as tensile strength, Young’s modulus, and elongation. Furthermore, the lap shear strength of the specimen was tested with UTM while impact resistance was measured with Izod impact tester. The composite whose molar ratio of epoxy resin to curing agent is 1 : 0.9 (sample 3), showed better tensile strength, coefficient of elastic modulus, elongation, and impact strength than other composites did. The highest tanδ from dynamic mechanical analysis (DMA) was observed from sample 2 (epoxy resin: dicy = 1 : 0.7) while sample 3 showed slightly lower tanδ than that of 2. The morphology of the fracture surface of the cured composites from SEM showed that the number of subtle lines on the surface caused by impact increase as the contents of amine curing agent accrete. Furthermore, the viscosity change of sample 5 (epoxy resin: dicy = 1 : 1.3) was observed to confirm its storage stability.

A Study on the Effect of Improving Permeability by Injecting a Soil Remediation Agent in the In-situ Remediation Method Using Plasma Blasting, Pneumatic Fracturing, and Vacuum Suction Method (플라즈마 블라스팅, 공압파쇄, 진공추출이 활용된 지중 토양정화공법의 정화제 주입에 따른 투수성 개선 연구)

  • Geun-Chun Lee;Jae-Yong Song;Cha-Won Kang;Hyun-Shic Jang;Bo-An Jang;Yu-Chul Park
    • The Journal of Engineering Geology
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    • v.33 no.3
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    • pp.371-388
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    • 2023
  • A stratum with a complex composition and a distributed low-permeability soil layer is difficult to remediate quickly because the soil remediation does not proceed easily. For efficient purification, the permeability should be improved and the soil remediation agent (H2O2) should be injected into the contaminated section to make sufficient contact with the TPH (Total petroleum hydrocarbons). This study analyzed a method for crack formation and effective delivery of the soil remediation agent based on pneumatic fracturing, plasma blasting, and vacuum suction (the PPV method) and compared its improvement effect relative to chemical oxidation. A demonstration test confirmed the effective delivery of the soil remediation agent to a site contaminated with TPH. The injection amount and injection time were monitored to calculate the delivery characteristics and the range of influence, and electrical resistivity surveying qualitatively confirmed changes in the underground environment. Permeability tests also evaluated and compared the permeability changes for each method. The amount of soil remediation agent injected was increased by about 4.74 to 7.48 times in the experimental group (PPV method) compared with the control group (chemical oxidation); the PPV method allowed injection rates per unit time (L/min) about 5.00 to 7.54 times quicker than the control method. Electrical resistivity measurements assessed that in the PPV method, the diffusion of H2O22 and other fluids to the surface soil layer reduced the low resistivity change ratio: the horizontal change ratio between the injection well and the extraction well decreased the resistivity by about 1.12 to 2.38 times. Quantitative evaluation of hydraulic conductivity at the end of the test found that the control group had 21.1% of the original hydraulic conductivity and the experimental group retained 81.3% of the initial value, close to the initial permeability coefficient. Calculated radii of influence based on the survey results showed that the results of the PPV method were improved by 220% on average compared with those of the control group.

Velocity-effective stress response of $CO_2$-saturated sandstones ($CO_2$로 포화된 사암의 속도-유효응력 반응)

  • Siggins, Anthony F.
    • Geophysics and Geophysical Exploration
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    • v.9 no.1
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    • pp.60-66
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    • 2006
  • Three differing sandstones, two synthetic and one field sample, have been tested ultrasonically under a range of confining pressures and pore pressures representative of in-situ reservoir pressures. These sandstones include: a synthetic sandstone with calcite intergranular cement produced using the CSIRO Calcite In-situ Precipitation Process (CIPS); a synthetic sandstone with silica intergranular cement; and a core sample from the Otway Basin Waarre Formation, Boggy Creek 1 well, from the target lithology for a trial $CO_2$ pilot project. Initial testing was carried on the cores at "room-dried" conditions, with confining pressures up to 65 MPa in steps of 5 MPa. All cores were then flooded with $CO_2$, initially in the gas phase at 6 MPa, $22^{\circ}C$, then with liquid-phase $CO_2$ at a temperature of $22^{\circ}C$ and pressures from 7 MPa to 17 MPa in steps of 5 MPa. Confining pressures varied from 10 MPa to 65 MPa. Ultrasonic waveforms for both P- and S-waves were recorded at each effective pressure increment. Velocity versus effective pressure responses were calculated from the experimental data for both P- and S-waves. Attenuations $(1/Q_p)$ were calculated from the waveform data using spectral ratio methods. Theoretical calculations of velocity as a function of effective pressure for each sandstone were made using the $CO_2$ pressure-density and $CO_2$ bulk modulus-pressure phase diagrams and Gassmann effective medium theory. Flooding the cores with gaseous phase $CO_2$ produced negligible change in velocity-effective stress relationships compared to the dry state (air saturated). Flooding with liquid-phase $CO_2$ at various pore pressures lowered velocities by approximately 8% on average compared to the air-saturated state. Attenuations increased with liquid-phase $CO_2$ flooding compared to the air-saturated case. Experimental data agreed with the Gassmann calculations at high effective pressures. The "critical" effective pressure, at which agreement with theory occurred, varied with sandstone type. Discrepancies are thought to be due to differing micro-crack populations in the microstructure of each sandstone type. The agreement with theory at high effective pressures is significant and gives some confidence in predicting seismic behaviour under field conditions when $CO_2$ is injected.

A Study on the Material and Production Method of Bronze Casting Earthen Mold - Focusing on Earthen Mold Excavated in Dongcheon-dong, Gyungju - (청동주조 토제범(土製范)의 재질과 제작기법 연구 - 경주 동천동 출토 토제범을 중심으로 -)

  • Son, Da-nim;Yang, Hee-jae
    • Korean Journal of Heritage: History & Science
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    • v.46 no.4
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    • pp.108-125
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    • 2013
  • This study examined the actual reconstruction drawing, composite mineral, particle size and property test, fine organic matters, color differences and main ingredients of the earthen mold excavated in Dongcheon-dong, Gyungju. The cross-section of the inner mold and outer mold divides into inside (1st layer) and outside (2nd layer), with organic matters mixed outside. The cross-section has been altered due to heat and form removal agent. X-ray analysis revealed that the layer was made of minerals with high transmissivity and only quartz particles were observed through a polarizing microscope. The inside of cross-section in SEM observation identified enlarged air gap, with crack developed in the center, but no changes observed on the outside. The particle size of the composites is almost the same for the inner mold and outer mold and is silt clay loam. The ratio between silt clay and silt clay loam was about 2.7:1 and 2.9:1 respectively. In the property test, the density and absorption rate of inner mold and outer mold were similar, but porosity was different, with inner mold of 27.36% and outer mold of 31.09%. The color difference of cross-section seems to have been caused by the spread of soot on the 1st layer surface for removal of form or by the covering of ink to protect the 1st layer. Composite mineral analysis revealed the same composition for the inner mold and outer mold, except for the magnetite that was detected in the inner mold alone. As for the main ingredient analysis, the average content of $SiO_2$ was 71.64% and that of $Al_2O_3$ was 14.59%. As for the sub-ingredients, $Fe_2O_3$ was 4.51%, $K_2O$ 3.06%, $Na_2O$, MgO, CaO, $TiO_2$, $P_2O_5$ and MnO was less than 2%.