• Korean Journal of Food Science and Technology
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• v.14 no.4
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• pp.342-349
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• 1982

Filefish muscle in the form of thin plate $(5{\times}10{\times}0.4\;cm)$ was dried in a forced air dryer at $47.5^{\circ}C$ to study the relation between dehydration mechanism and water activity. The dryer was designed in such a way that the temperature, relative humidity and velocity of air could be controlled. The whole dehydration process of the filefish muscle was divided into two different drying rate periods, constant and falling rate period. During the constant drying rate period, the drying rate was proportional to the square root of air velocity under the conditions of constant temperature and relative humidity of air. The falling rate period was further divided into two different falling drying rate periods, first and second falling rate period. The first falling rate period was an unsaturated surface drying period caused by partial unsaturation of the drying surface with capillary condensed free water diffused from the internal part of the filefish muscle. At this stage he drying rate was mainly dependent on the relative humidity at constant air temperature, and case-hardening phenomenon started at the end of this stage. The moisture content and the water activity at which the second falling rate period started were not constant, because the drying rate of the first falling rate period was strongly dependent on the air humidity. The second falling rate period was again divided into two drying rate periods, former and latter period. The drying rates of both of these periods were independent on the external air humidity. During the former period of the second falling rate period, the dehydration was proceeded by diffusion and vaporization of capillary condensed free water in filefish muscle. The diffusion coefficient of water was $2.89{\times}10^{-10}m^2/sec\;at\;47.5^{\circ}C$. At this stage, the case-herdening continued until the water activity reduced to 0.7. The latter period of the second falling rate period started at the water activity of 0.45. The dedydration was proceeded by diffusion and vaporization of bound water, which adsorbed in multimolecular layers, through the hardened drying surface. The number of molecular layers was 4, and the diffusion coefficient of water during this stage was $4.38{\times}10^{-11}m^2/sec\;at\;47.5^{\circ}C$.

• Journal of the Korean Wood Science and Technology
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• v.4 no.1
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• pp.48-53
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• 1976

This Study was carried out to investigate the course of air-drying and drying defects of red pine (Pinus densiflora S. et Z.) and Italian poplar (Populus eurameriana I-476) boards 1,2 and 3cm thick in the flat pile. The results are as follows. 1. Air-drying curves for red pine and Italian poplar boards were same as figure 1 and 2. These moisture contents were lower in July and August during seasoning periods. 2. Air drying time of red pine board required to dry 15 percent moisture content in one week for 1 cm board, five weeks for 2 cm board and six weeks for 3cm board respectively. In case of Italian poplar boards, in one week for 1 cm board, four weeks for 2 cm and five weeks for 3 cm board. The thickness of board influenced the time for air drying. 3. Drying defects such as checking, warping and staining happened badly in pine than in Italian poplar boards. Especially, checking was severe in thicker board and warping in thinner board.

• Korean Journal of Plant Resources
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• v.14 no.2
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• pp.175-181
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• 2001

Dormancy of intact zoysiagrass seeds hinders its seed propagation in which presowing seed treatment must be done to overcome it. The study was done to remodel the presowing treatments of zoysiagrass seeds by determining the treatment effects of seedcoat softening, prechilling, drying and combined light treatment with them or during germination stage. Seedcoat softening with different chemicals (NaOH 20%, KOH 20%, $H_2SO_4\;8M, acetone 20%) and periods (10, 30, 60 min.), prechilling with different periods at 3$^{\circ}C$, and drying with 4 hours at 35$^{\circ}C$ was done. Light sources were also applied with 660 nm red LED light, commercial fluorescent and incandescent light and darkness. Germination test was done in alternative day and night temperature of 35 and 2$0^{\circ}C$ to check the daily germination rates. With seeds treated with NaOH 20% for 30 minutes, red and incandescent light showing similar responses inclined their germination rates compared to dark conditions. Drying resulted in its higher rate than non-drying but fluorescent light treatment forced during drying more enhanced the rate than red light. While mean germination rate considering all the seedcoat softening treatment periods was the greatest in $H_2SO_4$ in comparison with NaOH, KOH and acetone, NaOH treatment for 30 minutes showed the best rate among the all the treatment levels. In the conditions of sowing them to no-mulching field, presowing treatment procedure of zoysiagrass seeds was remodeled: the seedcoat softening treatment with NaOH 20% for 30 minutes was done, washed, and chilled at 3$^{\circ}C$ for 2 weeks before dried under 4 hour fluorescent light illumination at 35$^{\circ}C$.

• Korean Journal of Pharmacognosy
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• v.50 no.4
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• pp.312-317
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• 2019

In order to obtain basic data on the shelf life of Epimedii Herba (EH), a physicochemical characteristics including weight loss rate, loss on drying, ash, acid-insoluble ash, and quantitative determination were evaluated to compare the data by packaging methods including general (G), general + silica gel (GS), alumium (AL), and alumium + silica gel (ALS) packaging and storage periods (0-66 months). All physicochemical analyzes were conducted using the method of "The Korean Pharmacopoeia (KP) 9^th edition". As a result, weight loss rate (%), loss on drying (%), ash (%), acid-insoluble ash (%) of EH according to the packaging methods and storage periods were -0.27-4.73%, 3.06-9.35%, 5.48-7.37%, and 0.45-0.99, respectively. In the quantitative analysis of icariin, the marker compound of EH using high-performance liquid chromatography, the initial content was 0.44% at 0 month in all packaging methods. After that, the result of analyzing the content of icariin every 6 months was detected 0.44-1.18%. All of the above results satisfied the acceptance criteria for loss on drying, ash, acid-insoluble ash, and quantification contained in the KP. This study can be used as a basic data for establishing the packaging method and shelf life of EH.

• Journal of Animal Environmental Science
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• v.3 no.2
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• pp.133-143
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• 1997

Optimal conditions for collecting, storing and drying temperature to utilize slaughter porcine blood for blood meals and the effects of blood meal on growth in broiler chicks were investigated. Dry matter and protein contents of slaughter procine blood were 19.5% and 77%(dry basis), respectively. As for the composites of amino acids in the blood, aspartic acid, arginine, glycine, histidine, leucine, lysine, phenylalanin threonine were shown high. There was no significant difference between the collections by bloodletting and vacuumming in terms of microbial contamination. Storage of slaughter porcine blood showed no differences in protein, DNA and triglyceride contents and pH between the storage methods of freezing (-20$^{\circ}C$) and refrigerating (-4$^{\circ}C$). In case of room temperature storage, however, the decrease in pH and the appearance of new protein due to microbial contaminations increased as the storage periods were prolonged. When drying was done by flash methods, the drying period got shortened as the temperature became higher, yet protein and triglyceride were destoryed more. When drying was done over 120$^{\circ}C$, even at the same degree, the breakdowns of protein and triglyceride increased more as drying period got longer. In feeding trials of broiler chicks, dietary supplementation of the flash dried blood meal at 2% level showed significant difference in growth rate(P＜.05%). These results indicated that the appropriate handling and manufacturing of slaughter porcine blood enabled the blood to be used as a protein source for broiler chicks.

• Restorative Dentistry and Endodontics
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• v.49 no.2
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• pp.20.1-20.13
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• 2024

Objectives: This study investigated the nanoleakage of root canal obturations using calcium silicate-based sealer according to different drying methods. Materials and Methods: Fifty-two extracted mandibular premolars with a single root canal and straight root were selected for this study. After canal preparation with a nickel-titanium rotary file system, the specimens were randomly divided into 4 groups according to canal drying methods (1: complete drying, 2: blot drying/distilled water, 3: blot drying/NaOCl, 4: aspiration only). The root canals were obturated using a single-cone filling technique with a calcium silicate-based sealer. Nanoleakage was evaluated using a nanoflow device after 24 hours, 1 week, and 1 month. Data were collected twice per second at the nanoscale and measured in nanoliters per second. Data were statistically analyzed using the Kruskal-Wallis and Mann-Whitney U-tests (p < 0.05). Results: The mean flow rate measured after 24 hours showed the highest value among the time periods in all groups. However, the difference in the flow rate between 1 week and 1 month was not significant. The mean flow rate of the complete drying group was the highest at all time points. After 1 month, the mean flow rate in the blot drying group and the aspiration group was not significantly different. Conclusions: Within the limitations of this study, the canal drying method had a significant effect on leakage and sealing ability in root canal obturations using a calcium silicate-based sealer. Thus, a proper drying procedure is critical in endodontic treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.503-508
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• 1991

The salted and dried mullet(Mugil Japonicus) roe had about 42% of protein and 41% of lipid content as major compoments. Therefore the lipid oxidation and the deterioration of protein occurred during drying and storage periods. In order to keep the good quality of the dried roe, acid, peroxide, thiobarbituric acid value and the contitutional amino acid were studied in the different drying air velocities at the conditions of 60% R.H. and $20^{\circ}C$ of drying air temperature. The optimum air velocity showed 2m/sec, which was excellently superior to the lipid and protein quality than those of other air velocities on the dried mullet roe. The drying period shortened from 20 days in the conventional processing method to 7 days in the modified processing method that had 2m/sec of drying air velocity. The drying rate curve had only a falling-rate drying period and not to have a constant-rate drying period.

• Journal of Animal Environmental Science
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• v.8 no.3
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• pp.177-182
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• 2002

Drying process is very important for commercialization of velvet antlers. So far, artificial drying has mostly depended on experience of farmers resulting in low efficiency of drying, deterioration during drying, and contamination by dust and bacteria. Various drying techniques for high-quality production have currently been commercialized in some developed countries, and one of them is a drying technique using microwave. In this study, application of the technique using an electronic (microwave) oven for drying of velvet antler was investigated. The results of this study are as follows. 1. It was found that the drying period was significantly affected by cornification of velvet antlers. Accordingly, it can be assumed that the velvet antlers should partly be sliced to save drying period and required drying energy. 2. It was also found that the drying speed was changeable according to tempering period and even with same drying period. The tempering period should be controlled according to processing rate. 3. The results indicated that a repeated drying of 2-min drying and 3-min tempering is the most effective when a microwave oven was used. 4. The results also showed that the drying technique using microwave of electronic oven can be effectively used for drying of velvet antlers. 5. Only drying and tempering periods were examined in this study, however, ingredient change of deer antler after drying is necessary to be investigated in the future.

• Journal of Mushroom
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• v.14 no.4
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• pp.215-219
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• 2016

The total polyphenol and physiological activities of Pleurotus ostreatus 30% fermented ethanol using different drying methods and extraction periods were investigated. Based on the observed polyphenol content and physiological activity, freeze-drying showed better results than hot air-drying method for P. ostreatus extracted with 30% fermented ethanol for more than 15 days. The total phenolic compound content of 'Gosol' following thefreeze-drying method for 15 days showed the highest value of $0.49{\pm}0.02mg/mL$. Freeze-drying with extraction for 30 days for ASI 2344 showed the highest antioxidant activity based on the DPPH radical scavenging rate of $35.50{\pm}3.29%$. Freeze-drying 'Gosol' for 30 days resulted inthe highest anti-inflammatory and nitrite scavenging activity of $48.40{\pm}3.38%$. Our results showed that P. ostreatus is a functional food.

• Computers and Concrete
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• v.14 no.6
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• pp.635-656
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• 2014

A rational estimation of moisture distribution in structural concrete is vital for predicting the possible extent and rate of progression of impending degradation processes. The paper proposes a numerical scheme for analysing the evolution of moisture distribution in concrete subjected to wetting-drying exposure caused by intermittent periods of rainfall. The proposed paradigm is based on the stage wise implementation of non-linear finite element (FE) analysis, with each stage representing a distinct phase of a typical wet-dry cycle. The associated boundary conditions have been constituted to realize the influence of various meteorological elements such as rain, wind, relative humidity and temperature on the exposed concrete surface. The reliability of the developed scheme has been demonstrated through its application for the simulation of experimentally recorded moisture profiles reported in published literature. A sensitivity analysis has also been carried out to study the influence of critical material properties on simulated results. The proposed scheme is vital to the service life modelling of concrete structures in tropical climates which largely remain exposed to the action of alternating rains.