• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.2
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• pp.89-96
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• 2011

In this study, increasing the range of replacement rate of FA with concrete properties were analyzed to provide basic data of FA replacement 0-40 % and curing temperature $5-35^{\circ}C$ range. As a result of the increased fluidity in proportion to the increase in FA, but decreased air. Setting time delayed at replacement rate increases and low temperature, simple insulation temperature history of the FA up to 40 % replacement rate increases the maximum temperature was low $8^{\circ}C$, the highest temperature reaching time delay of 13 hours. FA replacement up stream of the curing temperature, compressive strength compared to the higher plane, it was found that improved strength development. In carbonation tests with increasing the replacement ratio of FA carbonation depth was increased. Therefore, continued research on carbonation measures was to be necessary.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.2
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• pp.231-237
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• 1998

This study was carried out to investigate the effects of curing methods on the concentration of ammonia during curing in burley tobacco leaves. The air-cured tobacco(KB108; Nicotiana tabacum L.) was grown at Chonju Tobacco Experiment Station in 1998 and the tenth leaves from the top on the stalk were harvested. Half of the harvested leaves were cured in normal air curing facility and the other leaves were cured in excessive curing facility. Stalk cut tobaccos were cured in horizontal curing facility. The leaves were sampled every five days from harvesting time to the end of curing(25 days). Ammonia concentration of leaves increased during curing period with a remarkable increase at yellowing stage. The concentration of ammonia was high in the primed cured leaves, while that of the excessive cured leaves was low. It is considered that the lower increase of ammonia in stalk cured leaves may be caused by the translocation from the leaves to the stalk during curing, while that of excessive cured leaves may be caused by the poor decomposition of protein and amino acid during curing by excessive moisture loss and high temperature condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.130-136
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• 1987

The studies were carried out to investigate the occurrence of excessive dried leaves during burley tobacco curing. Six different periods of ventilation during the entire stage of curing were applied. And also 3 different heights of rolling up polyethlene film for side ventilation of the curing house combined with 4 different spaces between garlands were applied from after yellowing. The high air temperature and low relative humidity from end of yellowing to end of browning stage were the most critical to occur excessive dried \eaves. As side ventilation was continued for the entire stage of curing, air temperature in curing house was lower and occurrence of excessive dried leaves were remarkably decreased. The air temperature was not affected on hanging spaces, but relative humidity that resulted significantly in decreasing of the excessive dried leaves was increased by narrowing of hanging spaces. As excessive dried leaves were increased, its price per kg was lower, its physical properties was worse and its total nitrogen and total suger were higher than those of normal cured leaves.

• Restorative Dentistry and Endodontics
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• v.39 no.3
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• pp.155-163
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• 2014

Objectives: Light-curing of resin-based materials (RBMs) increases the pulp chamber temperature, with detrimental effects on the vital pulp. This in vitro study compared the temperature rise under demineralized human tooth dentin during light-curing and the degrees of conversion (DCs) of three different RBMs using quartz tungsten halogen (QTH) and light-emitting diode (LED) units (LCUs). Materials and Methods: Demineralized and non-demineralized dentin disks were prepared from 120 extracted human mandibular molars. The temperature rise under the dentin disks (n = 12) during the light-curing of three RBMs, i.e. an Ormocer-based composite resin (Ceram. X, Dentsply DeTrey), a low-shrinkage silorane-based composite (Filtek P90, 3M ESPE), and a giomer (Beautifil II, Shofu GmbH), was measured with a K-type thermocouple wire. The DCs of the materials were investigated using Fourier transform infrared spectroscopy. Results: The temperature rise under the demineralized dentin disks was higher than that under the non-demineralized dentin disks during the polymerization of all restorative materials (p < 0.05). Filtek P90 induced higher temperature rise during polymerization than Ceram.X and Beautifil II under demineralized dentin (p < 0.05). The temperature rise under demineralized dentin during Filtek P90 polymerization exceeded the threshold value ($5.5^{\circ}C$), with no significant differences between the DCs of the test materials (p > 0.05). Conclusions: Although there were no significant differences in the DCs, the temperature rise under demineralized dentin disks for the silorane-based composite was higher than that for dimethacrylate-based restorative materials, particularly with QTH LCU.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.214.2-214.2
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• 2013

Device performance for the 45 and 32 nm node CMOS technology requires the integration of ultralow-k materials. To lower the dielectric constant for PECVD and spin-on materials, partial replacement of the solid network with air (k=1.01) appears to be more intuitive and direct option. This can be achieved introducting of second "labile" phase during depositoin that is removed during a subsequent UV curing and annealing step. Besides, with shrinking line dimensions the resistivity of barrier films cannot meet the International Technology Roadmap for Semiconductors (ITRS) requirements. To solve this issue self-forming diffusion barriers have drawn attention for great potential technique in meeting all ITRS requirments. In this present work, we report a Cu-V alloy as a materials for the self-forming barrier process. And we investigated diffusion barrier properties of self-formed layer on low-k dielectrics with or without UV curing treatment. Cu alloy films were directly deposited onto low-k dielectrics by co-sputtering, followed by annealing at various temperatures. X-ray diffraction revealed Cu (111), Cu (200) and Cu (220) peaks for both of Cu alloys. The self-formed layers were investigated by transmission electron microscopy. In order to compare barrier properties between V-based interlayer on low-k dielectric with UV curing and interlayer on low-k dielectric without UV curing, thermal stability was measured with various heat treatment temperature. X-ray photoelectron spectroscopy analysis showed that chemical compositions of self-formed layer. The compositions of the V based self-formed barriers after annealing were strongly dominated by the O concentration in the dielectric layers.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.1
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• pp.85-91
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• 2004

The purpose of this study was to observe in vitro pulp chamber temperature rise during composite resin polymerization with various light-curing sources. The kinds of light-curing sources were plasma arc light(P), low heat plasma arc light, traditional low intensity halogen light, low intensity LED(L-LED), and high intensity LED(H-LED). Temperature at the tip of light guide was measured by a digital thermometer using K-type thermocouple. Occlusal cavities$(2{\times}2{\times}1.5mm)$ were so prepared in extracted human premolars as to the remaining dentin thickness was 1mm. Dentin adhesive was applied to all cavities. Experimental groups consisted of no base group, ionomer glass base group, and calcium hydroxide base group. Temperature before and after resin filling was measured. Temperature at the light guide tip was the highest with P and the lowest L-LED. Temperature before resin filling was the highest with H-LED and the lowest with L-LED. Temperature after resin filling was the highest with H-LED and the lowest with L-P and with L-LED. The lining of base partially reduced the temperature rise.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.781-784
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• 2008

In this paper, insulating effect and strength development of concrete under low temperature are reported varying curing sheets. According to test results, in temperature -5$^{\circ}$C concrete subject to exposure and air cap condition, result in a frost damage at early age by a fall of below zero temperature. Mean while, the combination of PE film and non-woven fabric maintained around 3 $^{\circ}$C within first 24 hours since placement. For double bubble sheets, concrete temperature maintained above 7$^{\circ}$C due to its excellent heat insulating capability. As a result of core strength test, strength of specimens cured with viny + non-woven fabric and double bubble sheets had higher strength than strength of other specimens due to good heat insulation effect at early age.

• Journal of the Korea Concrete Institute
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• v.12 no.2
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• pp.31-42
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• 2000

This paper discusses the validity of models predicting the compressive strength of concrete subjected to various temperature histories and the shortcomings of existing rate constant model and apparent activation energy concept. Based on the discussion, a modified rate constant model is proposed. The modified rate constant model, in which apparent activation energy is a nonlinear function of curing temperature and age, accurately estimates the development of the experimental compressive strengths by a few researchers. Also, the apparent activation energy of concrete cured with high temperature decreases rapidly with age, but that of concrete cured with low temperature decreases gradually with age. Finally generalized models to predict apparent activation energy and compressive strength are proposed, which are based on the regression results.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.117-124
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• 1997

In this study, mechanical properties of type V cement concrete with different curing temperature were investigated. The tests for mechancial properties, i.e., compressive strength and modulus of elasticity, were carried out on two kinds of type V cement concrete mixes. concrete cylinders cured at 10, 23, 35 and 50℃ were tested at 1, 3, 7 and 8 days. The 'rate constant model' was used to described the combined effects of time and temperature on compressive strength development. Test results show that concrete subjected to high temperature at early age attains greater strength than concrete to low temperature but eventually attains lower later-age strength than that. With type V cement concrete, the linear and Arrhenius rate constant models both accurately describe the development of relative strength as afunction of the equivalent age.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.745-750
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• 2001

This study is about application to real construction site of estimating a early strength with use of microwave. Based on the exist studies, it is tried to confirm the correlation between curing temperature and estimating early strength method with microwave. The result of this study are as follows. 1) Coefficient figure of common use concrete's accelerating strength and 28 days strength after curing at $10^{\cire}C$, $20^{\cire}C$, $30^{\cire}C$ is 0.84, 0.80, 0.80 2) Coefficient figure of concrete's-has a low fine aggregate ratio- accelerating strength and 28 days strength after curing at $10^{\cire}C$, $20^{\cire}C$, $30^{\cire}C$ is 0.86, 0.82, 0.81