• Korean journal of food and cookery science
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• v.15 no.1
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• pp.37-41
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• 1999

Colored rice (Suwon 45) flour was evaluated as a bread flour by the addition of 10% gluten on 3% hydroxypropyl methyl cellulose to check the processing adaptability. Both of these additives led to a successful formation of rice bread. Textural characteristics of colored rice bread crumb baked with 3% hydroxypropyl methyl cellulose revealed lower hardness and chewiness, however, the one with 10% gluten revealed the higher springiness. The retrogradation of colored rice bread during storage was not significantly different from that of wheat bread. Sensory evaluation showed that the crumb texture of bread baked with 3% hydroxypropyl methyl cellulose had softer texture and poor distribution of air-pore size but its springiness was not significantly different from that of wheat bread.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.740-745
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• 2015

Hydroxypropyl cellulose (HPC) composite films filled with TEMPO-oxidized cellulose nanofibrils (TOCN) were prepared in this study. In order to investigate mechanical and thermal properties of HPC/TOCN composite films, tensile strength and thermogravimetric analysis (TGA) wer performed. As the loading level of TOCN increased, the tensile strength and modulus increased significantly. However, thermal stability of HPC/TOCN composite films was not related to the loading levels of the TOCN.

• Journal of the Korean Society of Safety
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• v.22 no.5
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• pp.77-83
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• 2007

This study is conducted on spontaneous ignition temperature and activation energy of Hydroxypropyl Methyl Cellulose(HMC) powder. HMC is a kind of cellulose derivative and used as additives for building material, surface coating, printing ink, adhesives, cosmetics and medical supplies. So this material has been widely used as important additive in the chemical industry fields and a mount of production has increased year by year. Therefore, it is very important to find out the thermal ignition characteristics of its danger and the critical ignition temperature. This study was performed by the Spontaneous Ignition Tester(SIT) and so on. Based on the data of the SIT-II, the critical ignition point of HMC is about $186^{\circ}C$ which is slightly lower than normal cellulose.

• Polymer(Korea)
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• v.25 no.4
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• pp.545-557
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• 2001

The crosslinked films retaining cholesteric liquid-crystalline order were prepared by casting the liquid crystalline solutions of hydroxypropyl cellulose (HPC) in methanol with the two kinds of aliphatic dicarboxylic acid chlorides (succinyl chloride and suberoyl chloride). The temperature dependence on the cholesteric pitch of the crosslinked films and the swelling behavior of the films in both water and methanol were investigated. The films displayed fingerprint patterns charateristic of cholesteric liquid-crystalline phase, and their pitches, as well as HPC itself, increased with temperature. However, the pitch of all crosslinked samples was much greater than that of HPC at the same temperature and increased with increasing concentration and chain length of the crosslinker. The crosslinked samples exhibited an anisotropic swelling in both solvents. The degree of anisotropy slightly depended on the solvent and crosslinker species, but hardly on the crosslinker concentration investigated.

• Korean Journal of Food Science and Technology
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• v.29 no.4
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• pp.700-704
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• 1997

Fermentation and morphological characteristics of rice bread baked with gums, lipids, and glutens added dough were investigated to establish the standard recipe for rice bread processing. All gum-type additives 1ed to successful formation of rice bread. Hydroxypropyl-methyl-cellulose among tested gums showed the best volume expansion and successful formation of rice bread. Addition of vegetable oils gave better effect on increasing the specific loaf volume and tenderness of rice bread than addition of the solid-type lipids such as margarin and lard during rice bread processing. Dry heating during baking of the rice bread gave more desirable effect on specific gravity of rice bread than wet heating. High-amylose rices such as Suweonjo, AC 27, and IR 44 showed better formation of rice bread in the case of adding 3% hydroxypropyl-methyl-cellulose, while Suweon 230 and Pusa-33-30 showed slightly better formation of rice bread in the case of adding the gluten and strong hard flour. The glutinous rice Hangangchalbyeo failed to the formation of rice bread in both cases of adding 3% hydroxypropyl-methyl-cellulose and the gluten and hard flour.

• Journal of the Korean Society of Safety
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• v.15 no.4
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• pp.95-100
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• 2000

This study was performed in Hartmann type dust explosion apparatus in order to research the dust explosion characteristics of hydroxypropyl methyl cellulose(HPMC): minimum explosive limit, minimum ignition energy, limiting oxygen concentration, maximum explosion pressure, rate of pressure rise, etc. The samples of HPMC dust were distributed into 120-140 mesh, 170-230 mesh and 325 under, and the gap distance of the discharge electrode was setted up at 5mm. The experimental results were obtained as follows: (1) The minimum explosive limit for HPMC dust was founded at 180g/㎥. the minimum ignition energy at 9.8mJ and the limiting oxygen concentration at 12%. (2) The maximum explosion pressure of HPMC dust was $8.1kg/cm^2\;{\cdot}\;$abs at the concentration of $500g/m^3$ and the maximum rate of pressure rise was 203.98 bar/sec at the concentration of $480g/m^3$ for 325 under.

• Polymer(Korea)
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• v.38 no.3
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• pp.338-350
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• 2014

Cellulose acetate (CA) fiber mats containing inclusion complexes of asiaticoside (AC) in 2-hydroxypropyl-${\beta}$-cyclodextrin ($HP{\beta}CD$) for potential usage as wound dressings were developed. The AC/$HP{\beta}CD$ complex-loaded CA fibers at various $HP{\beta}CD$ to AC molar ratios of 0.5, 1, and 2 were prepared in 90:10 v/v mixture of 80% (v/v) acetic acid and N,N-dimethylacetamide (DMAc) via electrospinning. The maximum released amounts of AC depended on the $HP{\beta}CD$ content and were much greater than those released from the AC-loaded CA fiber mat. In the in vitro study, indirect cytotoxic evaluation with human dermal fibroblasts (HDFa) showed that these materials released no substances in the levels that were harmful to the cells and the cells appeared to attach and proliferate well on these substrates. However, only the CA fiber mats containing AC/$HP{\beta}CD$ complexes at the $HP{\beta}CD$ to AC molar ratio of 0.5 was effective in upregulating the production of collagen of the cultured cells.

• Polymer(Korea)
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• v.25 no.2
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• pp.279-292
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• 2001

Two kinds of (hydroxypropyl)cellulose(HPCs) with different molar substitution (MS) and three types of derivatives based on the HPCs: (acetoxypropyl)celluloses, (ethoxypropyl)celluloses, and (cyanoethoxyprofyl)celluloses were synthesized, and their thermal and mesomorphic properties were investigated. All samples, which exhibit cholesteric reflection colours at room temperature, formed right-handed helicoidal structures whose optical pitches (λ$_{ms}$ ) increase with temperature. However, the isotropization ($T_{i}$) and glass temperatures, the magnitude of λ$_{m}$ of the mesophase at the same temperature, and the temperature dependence of λ$_{m}$ of the investigated derivatives highly depended on MS and the length and structure of the side chain introduced in HPC. The results were discussed in terms of the difference in the polarity and flexibility of the substituents and the distance between the main chains. For all derivatives, Am values approached infinity at temperatures above the $T_{i}$, of the mesophase, and no reversal in the sense of the pitch with temperature was detected.

• Polymer(Korea)
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• v.28 no.1
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• pp.92-102
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• 2004

(6-Cholesteryloxycarbonylpentoxypropyl)celluloses (CHPCs) with degree of esterification (DE) ranging from 2.25 to 2.91 were synthesized by reacting hydroxypropyl cellulose with 6-cholesteryloxycarbonylpentanoyl chloride. The acrylic esters of CHPCs (CHPCEs) and their photocrosslinked films with liquidcrystalline order were also synthesized. The thermotropic properties of mesophase for both uncrosslinked and crosslinked samples and the swelling behavior of the crosslinked samples in acetone were investigated. The hydroxypropyl cellulose exhibited an enantiotropic cholesteric phas, while all the uncrosslinked cholesterylbearing samples exhibited a monotropic cholesteric phases; the 6-cholesteryloxycarbonylpentanoyl chloride also showed a monotropic smectic phase. The hydroxypropyl cellulose formed a right-handed helix whose optical pitch (λ$\sub$m/) increases with temperature, whereas all the uncrosslinked derivatives farmed left-handed helices whose λ$\sub$m/'s decreased with temperature. The thermal stability of the mesophase and the magnitude of λ$\sub$m/ at the same temperature for both CHPCs and CHPCEs decreased with increasing DE. All the crosslinked samples, in constrast with CHPCEs, did not display reflection colors but exhibited an anisotropic swelling characteristic of crosslinked gel retaining liquid-crystalline order.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.212.2-212
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• 2003

Gluten 대체재료로써 gum질과 지방질 및 활성 gluten을 첨가하여 쌀빵의 특성을 비교 검토하였다. 실험에 사용한 모든 종류의 gum질 첨가에 의해서 쌀빵의 제조는 가능하였으며, 특히 3% hydroxypropyl-methyl-cellulose를 첨가하여 제조하는 경우 제빵의 성형성이 좋았다. 쌀빵 제조시 첨가하는 지방질로는 상온에서 액체상인 식용유를 사용하는 편이 고체상의 지방인 마아가린이나 라아드보다 쌀빵의 비용적을 증가시키며, 부드러운 조직감을 부여하고 있었다. 쌀빵 제조시의 가열방 법은 습식가열보다는 건식가열이 바람직한 결과를 얻었다. 3% hydroxypropyl-methyl-cellulose를 첨가하여 품종별 쌀로서 빵을 제조한 경우, 한강찰벼를 제외한 모든 품종에서 쌀빵 제조가 가능하였으며, 특히 수원조, AC 27, IR 44 등의 쌀로서 제조한 쌀빵의 성형성은 아주 좋았다. Gluten과 강력분을 첨가하여 제조하는 경우에도 한강찰벼를 제외한 모든 품종에서 쌀빵 제조가 가능하였으며, 수원 230이나 pusa-33-30등의 쌀로서 제조한 것이 다른 품종의 쌀보다 제빵성이 좋았다.