• Journal of Dairy Science and Biotechnology
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• v.33 no.3
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• pp.203-207
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• 2015

The majority of food drying processes are based on the use of thermal energy. However, such methods may deteriorate the quality of the final product. Freeze-drying is one of the most useful processes for drying thermosensitive substances. Food that contains beneficial bacteria, for example, is susceptible to heat treatment, but during freeze-drying beneficial bacteria are preserved in these food items. The primary goals of this study were to develop yogurt snacks and to compare the viability of lactic acid bacteria (LAB) in yogurt snacks under different freeze-drying temperatures. In addition, the survival of LAB during storage was investigated. Survival of LAB in freeze-dried yogurt snacks gradually decreased over 16 weeks of storage. LAB had a residual viability of 25.5% after 16 weeks of storage at room temperature. LAB survived better in freeze-dried plain yogurt snacks than in freeze-dried strawberry yogurt snacks during storage. Freeze-dried yogurt snacks contained 11.9% fat, 57.1% carbohydrate, and 18.7% protein. In conclusion, the viability of LAB in freeze-dried yogurt snacks depends on the temperature during freeze-drying: the higher the freeze-drying temperature, the lower the viability of LAB in yogurt snacks. The viability of LAB in yogurt snacks was also dependent on the moisture content and nutritional value.

• Korean Journal of Food Science and Technology
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• v.9 no.4
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• pp.245-250
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• 1977

Experiment were conducted to find out the effective drying method of citrus peel produced in Korea by varying the temperature of hot air, surface area of peels, peels from several citrus varieties and physicochemical treatment of the peel. 1. About $3{\sim}6\;days$ were required to reduce the moisture level of the peel from 70%(wet basis) to 20% at room temperature without forced convection. 2. Drying was speeded up until the temperature of hot air reached $60^{\circ}C$. Beyond that no significant increase in drying rate was observed. About 50 minutes were needed to reduce the moisture level (dry basis) to below 10% at $60^{\circ}C$ by forced convection 3. When the peel surface area was increased twice by cutting the peel into 256 fractions, the overall drying time (the time required to reduce the moisture level to 10%, dry basis) was shortened to 15 minutes from 50 mintes of the original peel. 4. No significant difference in drying rate was observed among the peels from several citrus varieties except Shaddock jabon and Citrus ponki tanaka, which dried more slowly than others. 5. Treatment of $Ca(OH)_2$ and the pressing of the peel before drying were effective in drying only when the initial moisture content was substantially higher.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.5
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• pp.18-23
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• 1999

This study examined the effects of multiple recycling on deinkability and properties of recycled paper from laser computer printout(LCPO). First, alkaline paper with a 20% printed area was disintegrated by TAPPI standard disintegrator. After dewatering , the pulp was followed by flotation, handsheet making, and drying at room temperature, in order. A sequence of printing , disintegrating, flotating , handsheet making and drying was one recycling cycle and this cyclic treatment was repeateed from zero to five times. The residual ink content in recycled handsheets by SEM-EDXA and Py-GC analyseswas increased slightly as recycling number increase. After five cycles of recycling the ISO brightness of recycled handsheets dropped to about 90% of the original brightness. However, it had a gain of 10% in opacity. The most of physical properties of recycled handsheets were decreased as recycling numbers increase except of for tear strength.

• Journal of the Korean Ceramic Society
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• v.25 no.3
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• pp.284-292
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• 1988

Alumina-zirconia composite powders for the purpose of improving fracture toughness and thermal shock resistance of alumina were prepared by the emulsion-kerosene drying method. The average particle size of composite powders was less then 1 $\mu\textrm{m}$ and their shapes were spherical. It was shown that the average particle size of composite powders decreased with the concentration of metal-salt in solution and the amount of span 80 added when preparing emulsions. The structure of all zirconia in composite powders heat-treated at 1200$^{\circ}C$ was a tetragonal form at room temperature. This result implied that fine zirconia particles were homogeneously dispersed in the alumina matrix.

• Archives of design research
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• v.18 no.4 s.62
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• pp.35-44
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• 2005

In the world, most of the metal technologists were as called as adornment artists than other field of industrial arts strongly industrial characters functional materials and manufacturing technology many used in the present age. In the study, one of adornments researched and material character analyzed about Art Clay Silver. The shrinkage rate of shape was about 0.24%. A shrinking phenomenon drying time thought of evaporation of water linking bonding agents and powders. After calcination of Art Clay Silver, the EDX used that just Ag 100% analyzed a result from the surface assay in the room temperature. A binder with powder in the room temperature considered to disappear, because it was been fume and smoke at high calcined temperature. A study showed when handicrafted necklaces make by these characteristic as using in difficult and delicated operations rather than naturally and beautifully expressive products.

• Journal of Biomedical Engineering Research
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• v.34 no.3
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• pp.117-122
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• 2013

Hyaluronic acid(HA) microbeads were synthesized by dropping the sodium hyaluronate(Streptococcus) solutions in NaOH into a solution mixture of divinyl sulfone(DVS) in 2-methyl-1-propanol, followed by stirring, cleaning and drying process at room temperature. The initial experimental conditions are crosslinking time(CLTi) of 5 h, crosslinking temperature(CLTe) of room temperature, injection air pressure(IAPr) of 5 psi, and DVS concentration( DVSc) of 0.2 vol%, respectively. Then, parametric studies were performed by varying the parameters to investigate the morphology, the porosity, the swelling ratio and the size of the beads. The microbead size pattern was not regular to function of the degree of crosslink. It was observed that the swelling ratio, the degree of crosslink, and the pore size can be controlled by adjusting the CLTi, CLTe and DVSc. Among the parameters investigated, the smallest bead size can be achieved by varying the CLTi parameter. The lowest swelling ratio, as an indication of the highest degree of crosslink, can be obtained by varying CLTe.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.56.2-56.2
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• 2012

Clinically-favored materials for bone regeneration are mainly based on bioceramics due to their chemical similarity to the mineral phase of bone. A successful scaffold in bone regeneration should have a 3D interconnected pore structure with the proper biodegradability, biocompatibility, bioactivity, and mechanical property. The pore architecture and mechanical properties mainly dependent on the fabrication process. Bioceramics scaffolds are fabricated by polymer sponge method, freeze drying, and melt molding process in general. However, these typical processes have some shortcomings in both the structure and interconnectivity of pores and in controlling the mechanical stability. To overcome this limitation, the rapid prototyping (RP) technique have newly proposed. Researchers have suggested RP system in fabricating bioceramics scaffolds for bone tissue regeneration using selective laser sintering, powder printing with an organic binder to form green bodies prior to sintering. Meanwhile, sintering process in high temperature leads to bad cost performance, unexpected crystallization, unstable mechanical property, and low bio-functional performance. The development of RP process without high thermal treatment is especially important to enhance biofunctional performance of scaffold. The purpose of this study is development of new process to fabricate ceramic scaffold at room temperature. The structural properties of the scaffolds were analyzed by XRD, FE-SEM and TEM studies. The biological performance of the scaffolds was also evaluated by monitoring the cellular activity.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.10a
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• pp.265-271
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• 1998

High temperature wear behavior of plasma sprayed zirconia based coating sealing with zirconia sol were investigated for high temperature wear resistance application. The zirconia powders containing 2.5, 5.0, 7.5, 10.0 mol% of MoS$_2$, $Fe_2O_3$ for plasma spray were made by spray drying method. As-sprayed coating was sealed by zirconia-sol to fill up the pore and crack in coating. wear test were performed at temperature ranges from room temperature to 600$\circ$C. The microstructural changes of before and after sealing process were examined by SEM, XRD and EPMA. After sealing process, the porosity was decreased and micro-hardness was increased. The wear properties of coating after sealing process were improved by sealing of pores and cracks. The behavior of wear amount and coefficient of friction were same tendency to before sealing process.

• Journal of Fisheries and Marine Sciences Education
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• v.29 no.3
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• pp.888-898
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• 2017

Tenebrio molitor larvae, also known as yellow mealworms (MW), are rich in protein and lipid and can serve as a potential alternative protein and energy source in commercial aquafeeds. Therefore, this study attempts to evaluate the effects of different drying methods on the nutritional value of MW meal. For this, live MW were cold-anaesthetized before being subjected to three different types of drying methods, including freeze-drying, oven-drying at $60^{\circ}C$ and air-drying at room temperature for three days, and compared for proximate composition and energy content. An in-vivo digestibility test was then conducted to evaluate the nutrient digestibility of MW meal in diets for rockfish, Sebastes schlegeli. A test diet was prepared by mixing the MW meal with a reference diet (Ref) in a 30:70 ratio with chromium oxide as an inert marker at the inclusion level of 0.5%. Rockfish with mean body weight of 150 g were stocked into a fecal collection system equipped with fiberglass tanks of 400 L capacity. Each group of fish was fed one of the experimental diets to apparent satiation for 4 weeks. The results of the proximate analysis showed that drying methods had no significant effect on crude protein, crude lipid, ash and energy contents of MW. Despite being a rich source of protein and lipid, MW meal was deficient in certain amino acids, particularly methionine, and highly unsaturated fatty acids, particularly 22:6n-3 (DHA) and 20:5n-3 (EPA). MW meal showed high digestibility values for protein (93%), lipid (97%) and energy (88%). These results may indicate that MW meal is a nutritious and acceptable feed ingredient, with comparable digestibility values to conventional animal and plant feedstuffs such as fish meal and soybean meal, in practical diet for rockfish at grower stage.

• 보존과학연구
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• s.32
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• pp.37-52
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• 2011

This study investigates the hardening characteristics of the mixture lacquer and glue at room temperature. Diverse samples were made from manufacturing of glue to the adding ratio in sap of the lacquer tree. After the examination of moisture content of samples, it has been seen that there is no relation with glue's kinds or adding ratio, but only with contain level of moisture. The samples made with film shape in order to examine the drying time. Samples with isinglass needed for over three days and had smooth surface. However, samples mixed with animal glue dried within a day and had ripples on the surface because of fast drying rate. In addition, the samples with isinglass had slow change of colour in early step of drying and no colour difference after completely drying although it had significant changes to black oxide as soon as contact with air. In structural analysis with FT-IR showed that the carbonyl bond increased in the samples of mixed with glue, compared to raw lacquer and treated lacquer.