• KSBB Journal
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• v.25 no.2
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• pp.137-141
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• 2010

Citric acid is a natural preservative and is used to add a sour taste to foods and soft drinks. For the preparation of stable food additives of citric acid, a coating process using vegetable oil was developed. Coating materials used were purified soy bean oil and carnauba wax. The yield of coated citric acid was up to 95% in both cases. The contents of coating materials was 20~33% in the total composition and the coating efficiency was 95.2 ${\pm}$ 0.01%. The surface of coated citric acid was much smoother and more homogeneous than that of original citric acid according to SEM data. The coated citric acid can be used to as a stable food additive and also would be applied to nutraceuticals and cosmetic ingredients.

• Journal of Conservation Science
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• v.28 no.1
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• pp.53-62
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• 2012

The archival objects are tangible evidence related to the public service. They are unique and offer information representing the specific events, time or person. The archival objects as modern cultural heritage do not have the guideline to classify, manage and conserve them. Especially, it is difficult to apply general conservation process for burial artifacts, because there are few study example of conservation for metal archival objects and they have complex administrative value. We tried to find suitable material and application method for consolidation of copper alloy archival object. We choose three kinds of wax and acrylic resin for burial artifacts and had done comparative analysis of their characterizations following kinds and coating methods. As a result of evaluation by several surface analysis such as optical microscope, measuring film thickness, adhesive strength, contact angle and yellowing test, acrylic resin can use to archival objects of copper alloy, effectively but the method of heating after dip-coating with Wax B used before can get best effect of consolidation.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.865-869
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• 2008

Effects of chitosan coating on respiration rate and internal gas composition of 'Fuji' apple and 'Satsuma' mandarin were investigated and compared to wax emulsions and two commercial coating materials. Chitosan coating reduced respiration rate significantly (p<0.05) in 'Fuji' apple and 'Satsuma' mandarin compared to uncoated and other coating materials. Chitosan coating on 'Fuji' apple showed the highest $CO_2$ and the lowest $O_2$ concentration in the internal gas composition at $5^{\circ}C$ but showed no differences compared to other coating materials at $20^{\circ}C$. 'Satsuma' mandarin showed significantly high $CO_2$ concentration in chitosan coating at $20^{\circ}C$ but there were not significant differences among coating materials in $CO_2$ and $O_2$ composition at $5^{\circ}C$.

• Korean Journal of Agricultural Science
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• v.20 no.1
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• pp.9-17
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• 1993

Postharvest treatments such as polyethylene film wrapping, ethylene scrubber, and fruit coatings were compared to find a potential effect on the fruit quality in 'Fuji' apples during storage and simulated marketing. Polyethylene film wrapping appeared to be excellent in preventing weight loss during storage but fruits lost weight at a high rate when exposed to ambient temperature during simulated marketing. Also, surface cracking disorder was observed in parts of film-wrapped fruit under marketing condition after storage of 21 weeks. Ethylene scrubber effectively removed ethylene in polyetheylene bags but this effect reduced along with the increase of storage time. Although Prolong-treated fruits were good in appearance at 12-week storage, no beneficial effect was found on the inhibition of weight loss during storage as well as marketing. In addition, wax-like substances were accumulated on the surface after storage of 21 weeks, resulting in the reduction of marketability. Water soluble wax seemed highly effective on the inhibition of weight loss during storage and marketing. However, parts of fruit were severely injured probably due to the high concentration of wax. Undamaged fruit showed excellent appearance in shape and flesh quality even after 21 weeks of storage. Further study is required to find the proper concentration of wax.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.135-137
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• 1968

Bathythermograph (B. T) has been coumonly used to obtain a records of water temperature in the depth of 270m from the surface. We have, however, experienced some difficulties in obtaining smoked or coated glass which is used for the bathythermograph in this region, Therefore I introduce a easy method of preparing the smoked-glass slide. Preparing method is as follows. 1. Glass slides must be cleaned by dipping into the concentrated solution of sodium hydroxide ana hydrochloric acid then rinsing with hot water and polishing with a clean gauge. 2. The cleaned slide is immersed in the wax solution for coating, and dried on the filter paper. The Wax solution is prepared as follow : 1g of white wax is dissolved in 200CC of benzol or 1g of lard is dissolved in 300CC of gasoline. 3. A slide held in a fingertip is smoked on the flame of alcohol lamp, or Meter burner. When alcohol lamp is used the fuel alcohol must contain 1/5 of benzol, and when Meker burner is used, the air intake must be blocked up. The smoking on the glass slide should be light and uniform, after smoking the slide is cooled down. 4. The smoked glass slide is again dipped into the wax solution using a fingertip and the excessive wax solution on the slide is absorbed on the filter paper and drain off. 5. Thus prepared smoked slide can be used for B.T.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.6
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• pp.52-57
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• 1999

Funtional metal prototypes are often required in numerous industrial applications. These components are typically needed in the early stage of a project to determine form, fit and function. Recent R/P(Rapid Prototyping) part are made of soft materials such as plastics, wax, paper, these master models cannot be employed durable test in real harsh working environment. Parts by direct metal rapid tooling method, such as laser sintering, by now are hard to get net shape, pores of the green parts of powder casting method must be infiltrated to get proper strength as tool, and new type of 3D direct tooling system combining fabrication welding arc and cutting process is reported by song etc. But a system which can build directly 3D parts of high performance functional material as metal part would need long period of system development, massive investment and other serious obstacles, such as patent. In this paper, through the rapid tooling process as silicon rubber molding using R/P master model, and fabricate wax pattern in that silicon rubber mold using vacuum casting method, then we tranlsated the wax patterns to numerous metal prototypes by new investment casting process combined conventional investment casting with rapid pototyping & rapid tooling process. with this wax-injection-mold-free investment casting, we developed new investment casting process of fabricating numerous functional metal prototypes from one master model, combined 3-D CAD, R/P and conventional investment casting and tried to expect net shape measuring total dimension shrinkage from R/P part to metal part.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.11
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• pp.1135-1140
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• 2012

Two-step metallization processes have been proposed to achieve high-efficiency silicon solar cells, where the front-side grids are formed by silver plating after the formation of a nickel seed layer with a mask. Because the conventional mask patterning process is performed by an expensive selective printing method using either UV resist or phase change ink, however, the combination of a simple coating and laser-selective ablation processes is proposed in this study as an alternative means. As a masking material, the solar cell wafer was coated with either inexpensive wax having a low melting temperature or a fluorocarbon solution, and then, an electrode image was patterned by selectively removing the masking material using the laser. It was found that the fluorocarbon coating was not only superior to the wax coating in terms of pattern uniformity but it also increased the efficiency of the solar cell by 0.16%, as confirmed by statistical f and t tests.

• Applied Microscopy
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• v.42 no.3
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• pp.147-150
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• 2012

A recently introduced helium ion microscopy (HIM) was employed to observe uncoated pine leaf specimens. Adult leaves were collected from the seedlings of Pinus densiflora and P. rigida, air-dried at room temperature, and observed by HIM without metal coating. Ovoid or round stomata and distinct Florin rings could be discerned. The epicuticular waxes were present in the epistomatal chambers and Florin rings of stomata on the leaf surface. The epicuticular waxes were mostly straight, cylindrical, and ca. 1 ${\mu}m$ in length. The epistomatal chambers of P. rigida were filled with the epicuticular waxes, whereas those of P. densiflora were not filled with the epicuticular waxes. Based on their micromorphology, the epicuticular wax structures of the pine species were identified as tubules. These results suggest that the HIM could be used for the investigation of the plant stomata and epicuticular waxes of uncoated plant leaves. Due to the smaller ion probe and interaction volume, the HIM has advantages over conventional field emission scanning electron microscopy in terms of image resolution and charge neutralization.

• 보존과학연구
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• s.30
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• pp.149-155
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• 2009

Annals of the Joseon Dynasty were composed of 1,229 volumes, and the 475 copies of total annals were wax-treated. Compared to non-wax treated copies, waxed volume of annals were seriously damaged such as crack, stick, discoloration to brown or black, and partially degradation. It is believed that the purpose of wax treatment for some volumes in the annals of the Joseon Dynasty is to prevent paper to deteriorate and to keep for the long time. But, beeswax could be deteriorated itself more rapidly. As a result, the waxed volume was much more damaged than non-waxed volume. Therefore, the investigation of decomposition and deterioration mechanism of beeswax-treated paper which might be used in waxed volume of the annals of the Joseon Dynasty must be done in order to prevent further decomposition and to restore the degraded wax-treated copies of the annals. For basis data of this purpose, physical properties of beeswax-treated paper be analyzed by coating methods. In result, sample products was manufactured reproducibility in lab scale. Specially, beeswax-treated method improved a orientation of papers. And the brushing method was stronger than the dipping method.

• Journal of Applied Biological Chemistry
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• v.58 no.1
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• pp.61-64
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• 2015

As an edible coating, carnauba shellac wax (CSW) and lemongrass oil (LO) solution was prepared to extend the shelf life of 'Hongro' apples. During storage, there were significant differences in the populations of total aerobic bacteria, yeast, and molds between the coated apples and the control samples. The weight loss and vitamin C loss of apples coated with the CSW-LO solution were lower than those of the control. These results suggest that CSW-LO coating can be an effective method for improving quality of 'Hongro' apples.