• Journal of the Korean Society of Tobacco Science
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• v.5 no.2
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• pp.9-15
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• 1983

The effect of leaf dehydration process and air flow capacity of bulk curing on physical properties and composition of cured leaves was studied, respectively, during flue- curing. Cured leaves from excessive moisture during yellowing stage and those from rapid dehydration Process inevitably during later stages, tend towards lower equilibrium moisture contents, higher shatter index, hither protein nitrogen, and leaf scalding or deterioration of Beaves with redish cast. Early dehydration at the yellowing stage re suited in increasing of p Bamitic, stearic, linoleic, and linolenic acid contents, but showed reduction of brightness difference between upper and lower surface of the cured leaves, Leaf surface lipid decreased with the progress of curing stages, more conspicuously during later stage. Lowering air flow capacity of fan by 50oye during stem drying stage resulted in increasing of leaf surface lipid and 25oye decreasing of electric power consumption , but curing period and kerosene consumption were not affected.

• Advances in concrete construction
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• v.9 no.1
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• pp.33-41
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• 2020

In this study, polyethylene glycol (PEG) and polyacrylamide (PAM) have been used as self-curing agents to produce self-curing concrete (SC). Compressive strength, ultrasonic pulse velocity (UPV), bulk electrical resistivity, chloride ion penetrability, water permeability, and main microstructural characteristics were examined under different curing regimes, and compared to those of the control concrete mixture with no self-curing agents. One batch of a control mixture and one batch of a SC mixture were air-cured in the lab to act as non-water-cured samples. The water curing regimes for the control mixture included continuous water curing for 3, 7, and 28 days and periodical moist curing using wetted burlap for 3 and 7 days. Curing regimes for the SC mixtures included 3 days of water curing and periodical moist curing for 3 and 7 days. SC mixtures showed better microstructure development and durability performance than those of the air-cured control mixture. A short water curing period of 3 days significantly improved the performance of the SC mixtures similar to that of the control mixture that was water cured for 28 days. SC concrete represents a step towards sustainable construction due to its lower water demand needed for curing and hence can preserve the limited water resources in many parts of the world.

• Korean Journal of Medicinal Crop Science
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• v.26 no.4
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• pp.291-295
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• 2018

Background: The use of Rehmannia glutinosa of the family Scrophulariaceae, in traditional medicine is well known. This study was conducted to elucidate the effect of air curing of the seed rhizome of R. glutinosa on its storability and yield. Methods and Results: The root of the R. glutinosa cultivar (Dagang) was harvested in at the end of November. The seed rhizomes were air cured for one to seven days. They were subsequently wrapped with newspaper and further stored in a plastic container at $1^{\circ}C$. It was observed that the weight loss and decay rates were significantly lower in the air cured seeds than in the untreated ones. Moreover, the decay rate of the control was approximately 50%, 120 days after storage. However. the decay rate of all the air cured treatment groups was less than 1%. Additionally, air curing led to an increase in the germination rate of the seeds and the root yield when compared with the untreated groups. Taken together, the ideal treatment period for air curing was found to be 3 days. Under these conditions, the germination rate and yield were 88.7% and 2,185 ㎏/10a, respectively. Conclusions: This study successfully demonstrated that the air curing of seed rhizomes can lead to a considerable increase in the storability and yield of R. glutinosa.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.181-186
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• 1999

When the expansive additives are used in concrete to reduce the shrinkage cracking, it shows variable properties with the curing method and curing temperature. Therefore, in this study, the experiments are perfomed to present the expansion of cement mortar by varying the unit additions of expansive additives and the curing method. According to the test results, the order of expansion by curing method, which is caused by hydration heat of cement, is follows ; curing at water > curing at air after curing at water for 7 days > curing at air. Cement mortar using expansive additives shows that high expansion is place with rise of temperature.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.239-240
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• 2022

In winter, low outdoor temperature can casue reduction of concrete strength. Therefore, thermal protection is required when curing concrete in winter to maintain a certain level or higher surface temperature. Accordingly, in domestic construction sites, a curing method in which surrounds casting areas by tents and operates hot air blowers are widely applied. However, local low-temperature areas may occur due to airtightness of the curing tents. If additional heat is supplied to prevent occurrence of local low-temperature areas, energy consumption increases. Therefore in this study, a plan for improvement method of concrete curing was considered and the performance was evaluated through numerical analysis. A plan to improve the airtightness of the wall opening was applied, but the analysis showed that if only a part of the curing area is shielded, the temperature of the unshielded area decreases,making it inappropriate to improve curing performance.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.1
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• pp.12-18
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• 2001

This study was conducted to investigate the effect of tobacco curing on far infrared light on the quality of flue-cured tobacco leaves. Physicochemical characteristics such as alkaloid, total sugar, total nitrogen, starch, total phenolic compounds, browning degrees, and color differences, in cured tobacco leaves were compared between hot air and far infrared curing methods. There was no significant difference in sugar/nicotine ratio and nitrogen number between the curing methods, while the contents of ether extract and filling capacity were increase by far infrared curing. Therefore, it was expected that far infrared curing might be effective for high aroma and physical properties of the cured tobacco leaves.

• Journal of the Korean Society of Tobacco Science
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• v.8 no.2
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• pp.19-27
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• 1986

This experiment was carried out to investigate the effect of circulating air volume to chemical composition of tobacco leaves during the bulk curing. The results were as follows : The decrease of circulating air volume prolonged curing time as the case of a 0.058m3/min. kg; but, no remarkable changes with a 0.11m3/min. kg and a 0.083m3/min. kg. When the circulating air volume was decreased, compared with 0.11m3/min. kg, sugar content was increased while total nitrogen and nicotine content showed a reduced values. In case of a 0.058m3/min. kg and a 0.083m3/min.kg, solanone and damascenone were high. Some of volatile neutral constituents and volatile organic acids were increased during curing process ; especially, their quantities were remarkably increased during the midrib drying stage. As circulating air volume decreased the equilibrium moisture content was increased, while leaf shatter index and filling capacity were decreased.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.183-188
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• 2009

RFID method is a non-contact automatic identification technology, which attaches microchips and antennas to an object in a tag form, to send and process information sent to the network using wireless frequency. Drying and curing process is extremely important which minimizes the resistivity of RFID antennas. This research is about the drying characteristic of conductivity ink, and analyzes and compares the hot-air drying process and infrared drying process. Also, the research was done for the improvement in drying performance by using combined process of hot-air and infrared mechanism. The experiment result shows that the hot-air or infrared drying system used alone cannot meet the required performance in drying printing method using conductivity ink. The combined drying system of hot-air and infrared ray showed resistance low enough in short drying and curing time, and this mechanism makes drying and curing process for mass and continuous production possible on-line.

• Journal of the Korean Society of Tobacco Science
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• v.14 no.1
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• pp.48-56
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• 1992

This studies were carried out to investigate the effects of leaf loading quantity and circulating air volume during bulk curing on the variation of physical and chemical characteristics in flue-cured tobacco. The results are as follows : 1. The content of sugar in cured leaves was decreased with more circulating air volume and leaf loading quantity at bulk curing. 2. Total nitrogen and protein nitrogen were decreased with less circulating air volume and more leaf loading quantity, while amino nitrogen was increased. 3. The contents of linolenic acid and linoleic acid were increased with more leaf loading quantity and oxalic acid and citric acid had a tendency of being increased in case of high circulating air volume. 4. In general, major aromatic compounds were increased through flue-curing. Relatively high content of solanone in case of lower air volume and less leaf loading were observed, while megastig matrienone was increased when leaf loading was small. 5. The more circulation air volume with leaf loading quantity caused lowering equilibrium moisture content and higher shatter index, which resulted in poor quality of cured leaves based on quality index, nitrogen number, taste index phillips index, and sugar-nicotine ratio.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.4
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• pp.51-56
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• 2014

After the preparation of low-cost conductive paste containing Ag-coated Cu flakes, thermal conductivity and electrical resistivity of the paste were measured with different curing conditions. Under air-curing conditions, the thermal conductivity of the cured sample increased with an increase of curing time from 30 to 60 min. After identical curing time of 60 min, the sample cured under nitrogen indicated more enhanced thermal conductivity than that cured under air, approaching that of paste containing pure Ag flakes. Under air-curing conditions, meanwhile, the electrical resistivity of the cured sample increased with an increase of curing time from 30 to 60 min. After identical curing time of 60 min, however, the sample cured under nitrogen indicated extremely enhanced electrical resistivity ($7.59{\times}10^{-5}{\Omega}{\cdot}cm$) in comparison with that cured under air.