• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1270-1277
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• 2003

The extrusion conditions of the soymilk residue and corn grits mixtures were optimized. The experiment was designed according to the D-optimal design of response surface methodology (RSM), which shows 18 experimental points including 4 replicates for three independent variables (screw speed, water content and die temperature). The responses variables such as bending force, expansion ratio, bulk density, water solubility index (WSI), water absorption index (WAI), and color values (L＊, a＊, b＊) were evaluated using response surface analysis. Expansion ratio and WSI decreased with increasing water content, whereas bulk density tended to increase with increasing water content. While greater screw speeds enhanced WSI and yellowness, higher moisture contents decreased the expansion ratio and WSI value. However, die temperature did not influence upon the response variables. The optimum extrusion conditions by numerical and graphical methods were similar: the screw speed, water content, and die temperature were 250 rpm, 22.43% and l28.16$^{\circ}C$ by the numerical method; 250 rpm, 22.43%, and 128.02$^{\circ}C$ by graphical method.

• Food Science and Preservation
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• v.15 no.3
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• pp.405-410
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• 2008

The rheological properties of dough made with 0%, 1%, 2% or 3% pine needle powder were investigated The approximate composition of the pine needle powder was moisture content 58.1% crude protein 4.1% crude fat 3.9% crude ash 0.9%, and crude fiber 9.3%. Rapid Visco Analyzer (RVA) analysis showed that the initial posting temperature increased with increasing pine needle powder content, while the peak viscosity decreased The water absorption, stability, development time, elasticity and valorimeter value of the dough, as determined using a farinograph and alveograph, decreased with increasing content of pine needle powder, while weakness increased. The extensibility, fermented volume and consistency of the dough decreased gradually with increasing pine needle powder content. These results indicate that addition of pine needle powder affects the rheological properties of bread.

• Journal of the Korean Applied Science and Technology
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• v.31 no.3
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• pp.345-351
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• 2014

Dinitramide ($N(NO_2)_2$) salts are one of plausible oxidizing agents for a high efficient propellant. Guanidine dinitramide (GDN) is an organic salt improving its stability against moisture, so that enables massive production and long term storage. Several types of GDN (GDN-1,2,3,4,5) were synthesized using some types of starting materials such as guanidine acetate, chloride, carbonate, nitrate and sulfate. As a result of the experimental work, synthesized GDN from the carbonate salt appeared fairly pure relatively higher yield (99%) than the other samples. The absorption wave length of all prepared GDNs by FTIR were found at 3452, 3402, 3354, 3278, 3208, 1642, 1570, 1492, 1416, 1337, 1179 and $1000cm^{-1}$. DSC analysis found a thermal phase change at $130^{\circ}C$, and indicated exothermic reaction at about $150^{\circ}C$ to $160^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• v.12 no.2
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• pp.130-137
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• 1991

The following new cryptand 221 complexes of lanthanides(Ⅲ) and dioxouranium(Ⅵ) nitrate have been synthesized: $(Ln(C_{16}H_{32}N_2O_5)(H_2O)_2(NO_3)_3\ and \((UO_2)_2(C_{16}H_{32}N_2O_5)(H_2O)_4(NO_3)_4$. These complexes have been identified by elemental analysis, moisture titration, conductivity measurements and various spectroscopic techniques. The proton and carbon-13 NMR as well as calorimetric measurements were used to study the interaction of cryptand 221 with La(Ⅲ), Pr(Ⅲ ), Ho(Ⅲ) and $UO_2(Ⅱ)$ ions in nonaqueous solvents. The bands of metal-oxygen atoms, metal-nitrogen atoms and O-U-O in the IR spectra shift upon complexation to lower frequencies, and the vibrational spectra ({\delta}NMN$) of metal-amide complexes in the crystalline state exhibit lattice vibrations below 300 $cm^{-1}$. The NMR spectra of the lanthanides(Ⅲ) and dioxouranium(Ⅵ) nitrate complexes in nonaqueous solvents are quite different, indicating that the ligand exists in different conformation, and also the $^1H$ and $^{13}C-NMR$ studies indicated that the nitrogen atom of the ring has greater affinity to metal ions than does the oxygen atom, and the planalities of the ring are lost by complexation with metal ions. Calorimetric measurements show that cryptand 221 forms more stable complexes with $La^{3+}$ and $Pr^{3+}$ ions than with $UO^{22+}$ ion, and $La^{3+}/Pr^{3+}$ and $UO^{22+}/Pr^{3+}$ selectivity depends on the solvents. These changes on the stabilities are dependent on the basicity of the ligand and the size of the metal ions. The absorption band (230-260 nm) of the complex which arises from the direct interaction of macrocyclic donor atoms with the metal ion is due to n-{\delta}*$ transition and also that (640-675 nm) of $UO^{22+}$-cryptand 221 complex, which arises from interaction between two-dioxouranium(Ⅵ) ions in being out of cavity of the ligand ring is due to d-d* transition.

• Journal of the Korean Society of Food Culture
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• v.34 no.3
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• pp.334-342
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• 2019

In this study, the effects of different varieties and particle sizes of dry milled rice flour on Jeolpyeon quality were investigated. Classify particle size of dry milled rice flour according to rice variety into 50, 100, and $150{\mu}m$. A particle size of $50{\mu}m$ in the varieties Boramchan and Hanareum resulted in the highest damaged starch contents (p<0.05). Additionally, the Boramchan and Hanareum varieties had the highest water absorption index (WAI) values (p<0.05). Analysis of the gelatinization characteristics of dry milled rice flour according to varieties revealed the peak viscosity of Dasan and Hanareum was high (p<0.05), regardless of particle size, while the breakdown was highest for Hanareum at all particle sizes (p<0.05). The moisture content of Jeolpyeon made with Boramchan varied between 48.83 and 53.64% among particle sizes, with no significant differences relative to the control. The hardness of the control was 3.15 kg, while the hardness of Jeolpyeon made with Boramchan decreased significantly 2.60-2.63 kg (p<0.05).

• The Journal of Engineering Geology
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• v.31 no.3
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• pp.257-267
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• 2021

Constraints on the structure and composition of the active layer are important for understanding permafrost evolution. Soil convection owing to repeated moisture-induced freeze-thaw cycles within the active layer promotes the formation of self-organized patterned ground. Here we present the results of ground penetrating radar (GPR) surveys across a selected sorted circle near King Sejong Station, Antarctica, to better delineate the active layer and its relation to the observed patterned ground structure. We acquire GPR data in both bistatic mode (common mid-points) for precise velocity constraints and monostatic mode (common-offset) for subsurface imaging. Reflections are derived from the active layer-permafrost boundary, organic layer-weathered soil boundary within the active layer, and frozen rock-fracture-filled ice boundary within the permafrost. The base of the imaged sorted circle possesses a convex-down shape in the central silty zone, which is typical for the pattern associated with convection-like soil motion within the active layer. The boundary between the central fine-silty domain and coarse-grained stone border is effectively identified in a radar amplitude contour at the assumed active layer depth, and is further examined in the frequency spectra of the near- and far-offset traces. The far-offset traces and the traces from the lower frequency components dominant on the far-offset traces would be associated with rapid absorption of higher frequency radiowave due to the voids in gravel-rich zone. The presented correlation strategies for analyzing very shallow, thin-layered GPR reflection data can potentially be applied to the various types of patterned ground, particularly for acquiring time-lapse imaging, when electric resistivity tomography is incorporated into the analysis.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.s01
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• pp.1-17
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• 1988

Rice Quality is considered to the five catagories ; the nutritional value: the characteristics of cooking. eating and processing: grain size, shape and appearance : milling yields: and storage characteristics. Because most rice is processed and consumed in whole-kernel form. the cooking and eating quality is of important and the physical properties of the intact kernel such as size, shape and general appearance are of particular significance in determining marketing quality. Eating Quality which can be directly evaluated by consumer's panel test is so complicate and variable, and thus the objective and simplified method of evaluation is required of using appropriate instruments. Even though many researches have been done to evaluate the eating quality in various aspects such as the texture of cooked rice kernels, amylogram analysis of rice powder, amylose content. gelatinization temperature. moisture absorption of rice kernel, and cooking characteristics, none of them is satisfied for the evaluation of eating quality. The improving eating quality should be also considered to many cultural factors. such as varieties, climatic and soil conditions, cultural method, handling after harvest. milling and storage conditions. In Korea, many researches in grain size. shape and appearance, and eating quality have been done with the varietal improvement mainly by rice breeders, but no effective method of evaluation was established. A few research have been done in the relationship between rice quality and cultural factors. In the future, research in rice quality should emphasize to establish the standard evaluation method in the physicochemical properties of rice kernels for application of varietal selection. and to develop cultural practices for the preserving quality characteristics of the varieties.

• Journal of Forest and Environmental Science
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• v.39 no.1
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• pp.55-64
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• 2023

Properties of a lesser-used wood species were investigated to determine its potential for structural utilization. Trees of Delonix regia were felled and sampled at the base, middle and top and then sectioned to inner wood, middle wood, and outer wood for variation across the axial and radial directions. Hence, selected physical and mechanical properties as well as natural durability of D. regia along the radial and axial directions were examined. Obtained data were analyzed using analysis of variance (ANOVA) at α_0.05. There was no significant difference in the Moisture content (MC) of the wood but specific gravity (SG) decreased from base to top ranging from 0.35-0.44. Water absorption, volumetric swelling, and volumetric shrinkage range from 46.18-51.86%, 2.57-4.02%, and 2.26-3.96% respectively along the axial plane. The weight loss for graveyard exposure and accelerated laboratory decay test ranged from 25.14-48.00% and 32.02-44.45% respectively. Modulus of Rupture and Modulus of Elasticity values range from 29.42-72.68 Nmm² and 3,834.54-8,830.37 Nmm² respectively. The SG values has confirmed the species as a medium density wood and values of other properties tested showed that the wood is dimensional stable and moderately resistance to fungi and termite. Hence, it could be used for light construction purposes such as furniture and other interior woodwork.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.36 no.4
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• pp.113-121
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• 2023

Objectives : The purpose of this study is to analyze the treatment mechanism of Thread-embedding acupuncture, which is used in Korean medicine beauty treatment. Methods : After searching papers published up to January 1, 2023 using the keyword "Thread-embedding" through the OASIS site, we selected beauty papers that mentioned the treatment mechanism of Thread-embedding acupuncture. Results : A total of 60 papers were retrieved: 19 papers on the topic of cosmetic diseases, 35 papers on the theme of other diseases, and 6 papers written unrelated to diseases. Among the 19 papers on the topic of cosmetic diseases, one unreadable paper was excluded. Among the 18 papers, we finally selected 6 papers that mentioned treatment mechanisms: 2 on facial wrinkles, 2 on obesity, 1 on breast enlargement, and 1 on transdermal hydration. The treatment mechanism of Thread-embedding acupuncture is that in the case of facial wrinkles, polydioxanone(PDO) is embedded to fill the volume, and as it decomposes, it causes a tissue reaction around the area. In obesity, it promotes fat decomposition by improving circulation, and promotes breast enlargement and elasticity through collagen formation. In transdermal hydration, it induces the production of surrounding fibers to increase skin elasticity and moisture. Conclusions : Thread-embedding acupuncture appears to have a cosmetic effect through a mechanism that promotes the production of collagen and elastic fibers in the subepidermal dermal layer and increases the activity of skin moisturizing factors during the absorption process after the PDO suture is embedded.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.496-505
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• 2023

This study explored a method to enhance the drying process usability of local mangoes by producing foam-mat dried powder under varying drying temperatures (50, 60, 70℃) and foam thicknesses (3, 6, 9 mm). The drying process period ranged from 60 to 390 minutes based on the set conditions, with higher temperatures and thinner foams accelerating drying. Powder chromaticity (L^*,(L^*, a^*, and b^*) demonstrated a declining trend with increasing drying temperature and foam thickness, exhibiting notable variance in chroma values. The water absorption index varied significantly, between 3.08 to 4.24, under different drying conditions, although the water solubility index remained consistent across foam-dried samples. Powder moisture content ranged from 2.53% to 3.83%, with hygroscopicity escalating with temperature and foam thickness. Vitamin C structure was compromised during the hot air drying process, especially at temperatures above 60℃. Electronic nose analysis distinguished foam-dried powder from freeze-dried powder; however, a thicker foam yielded a scent profile closer to that of freeze-dried powder. The findings provide fundamental data on mango foam drying, which is expected to improve processing and storage tech for local mangoes.