• Journal of the Korean Wood Science and Technology
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• v.51 no.1
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• pp.1-13
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• 2023

Sengon (Falcataria moluccana Miq.) tree offers a wood of low quality and durability owing to its low density and thin cell walls. This study aimed to improve the properties of sengon wood by making the wood magnetic, producing new functions, and characterizing magnetic sengon wood. Each wood sample was treated using one of the following impregnation solutions: Untreated, 7.5% nano magnetite-furfuryl alcohol (Fe₃O₄-FA), 10% nano Fe₃O₄-FA, and 12.5% nano Fe₃O₄-FA. The impregnation process began with vacuum treatment at 0.5 bar for 2 h, followed by applying a pressure of 1 bar for 2 h. The samples were then tested for dimensional stability and density and characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM-EDX), Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD) analysis, and vibrating sample magnetometry (VSM) analysis. The results showed that the Fe₃O₄-FA impregnation treatment considerable affected the dimensional stability, measured in terms of weight percent gain, anti-swelling efficiency, water uptake, and bulking effect, as well as the density of sengon wood. Changes in wood morphology were detected by the presence of Fe deposits in the cell walls and cell cavities of the wood using SEM-EDX analysis. XRD and FTIR analyses showed the appearance of magnetite peaks in the diffractogram and Fe-O functional groups. Based on the VSM analysis, treated sengon wood is classified as a superparamagnetic material with soft magnetic properties. Overall, 10% Fe₃O₄-FA treatment led to the highest increase in dimensional stability and density of sengon wood.

• Korean Journal of Materials Research
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• v.11 no.6
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• pp.512-518
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• 2001

It has been well known that 6.5wt% Si steel sheets have excellent magnetic properties such as low core loss. high maximum permeability and low magnetostriction. In this work, we studied a method for producing 6.5wt% Si steel sheets using a chemical vapor deposition (CVD) method. The following is the procedure adopted in this work to produce 6.5wt% Si steel sheets; SiCl$_4$ gas is applied onto a low content-Si steel sheet placed in a tube furnace. Silicon atoms resulted from the decomposition of SiCl$_4$ are permeated through the surface of the steel sheet. Finally, by the diffusion process maintaining it under a high temperature the silicon atoms diffuse uniformly into the sheet. Through this process, 6.5wt% Si steel sheets can be obtained. The manufactured Fe-6.5wt% Si steel sheet with a thickness of 0.5mm exhibited a high frequency core loss (W$_{2}$1k/) of 8.92 W/kg. Its permeability increased from 37,100 to 53,300 at 1 tesular(T). The mechanical properties of the manufactured steel sheets were also estimated and the result showed that the workability was significantly improved by annealing in vacuum at 773k. Increased plastic deformation was also observed prior to fracture and the amount of grain boundary rupture was reduced.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.858-864
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• 2001

This study was performed to investigate the effect of sodium lactate (SL, 60%) and a mixed fat replacer (FR) on the product quality and shelf-life effect of low-fat bologna sausage (LFBS) in a model system during refrigerated storage. Low-fat and regular-fat bologna sausages had pH values ranged from 6.15 to 6.30 and water activity values ranged from 0.95 to 0.96. LFBS had a moisture content of 74~76%, <2% fat and 14~15% protein, whereas regular-fat bologna had 60% moisture, 22% fat and approximately 12% protein in the final products. Expressible moisture (%) increased (p<0.05) in all bolognas, resulting in the soft texture, as the storage time (weeks) increased. LFBS manufactured with SL and a FR had lower (p<0.05) the cooking loss (%) and had higher (p<0.05) texture profile analysis (TPA) values than the regular-fat counterpart. As the sodium lactate level increased up to 5% in the formulation of LFBS, vacuum purge and TPA hardness values also increased (p<0.05), but thiobarbituric acid (TBA) values decreased (p<0.05). Total plate counts of LFBS were reduced (p<0.05) when the addition level of 60% SL solution was more than 3.3%. This result indicated that the increased level of SL (>3.3%) in the combination of a FR in the formulation of LFBS improved the product quality and did inhibit the total microbial growth of LFBS during storage, as compared to the control.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.24-32
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• 1984

In order to process instant foods which hold appropriate moisture contents and soft texture, four kinds of retort pouched seasoned-oyster products were prepared as control, seasoned products, solid smoked and liquid smoked product after seasoning and their processing conditions and quality stability during 100 days of storage were investigated. The optimum processing conditions of retort pouched seasoned-oyster product were as follows ; namely, raw oyster was seasoned at $105^{\circ}C$ for 10 min with seasoning solution prepared from sugar, sorbitol, salt, monosodium glutamate and 5'-ribonucleotide and then dipped for 30 seconds in Smoke-EZ solution(Alpha Foods Co., Ltd.) after predried for 30 min in hot-air drier. After. smoking, the seasoned and liquid smoked oyster was dried at $40-42^{\circ}C$ for 2.5 hours, vacuum packed in plastic film bag, and sterilized in a hot water circulating retort at $120^{\circ}C$ for 16 min. Comparing their quality before and after sterilization, TBA value of all the products after sterilization slightly decreased and among texture profiles hardness, toughness and chewiness slightly decreased, while elasticity and cohesiveness were rarely changed. Color value (a value) of the product treated with solid smoke or liquid smoke increased after sterilization. During storage pH, VBM and water activity of all products changed little and TBA values of the solid smoked product and liquid smoked one were lower than that of the others. Viable cell count was negative and texture changed little during storage. As for color difference during storage, green meat appeared on the surface of control and seasoned product after 15 days storage, while the masking of green meat could achieved by solid and liquid smoking treatment. And liquid smelling treatment was more effective than solid smoking. As a conclusion, retort pouched seasoned-oyster product treated with liquid smoke kept their good quality during 100 days storage and it seemed to be consumed as one of the instant foods which hold appropriate moisture contents and soft texture.

• Journal of the Korean Vacuum Society
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• v.20 no.6
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• pp.395-402
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• 2011

The nanomechanical properties of fully lithiated and unlithiated silicon nanowire deposited on silicon substrate have been studied with atomic force microscopy. Silicon nanowires were synthesized using the vapor-liquid-solid process on stainless steel substrates using Au catalyst. Fully lithiated silicon nanowires were obtained by using the electrochemical method, followed by drop-casting on the silicon substrate. The roughness, derived from a line profile of the surface measured in contact mode atomic force microscopy, has a smaller value ($0.65{\pm}0.05$ nm) for lithiated silicon nanowire and a higher value ($1.72{\pm}0.16$ nm) for unlithiated silicon nanowire. Force spectroscopy was utilitzed to study the influence of lithiation on the tip-surface adhesion force. Lithiated silicon nanowire revealed a smaller value (~15 nN) than that of the Si nanowire substrate (~60 nN) by a factor of two, while the adhesion force of the silicon nanowire is similar to that of the silicon substrate. The elastic local spring constants obtained from the force-distance curve, also shows that the unlithiated silicon nanowire has a relatively smaller value (16.98 N/m) than lithiated silicon nanowire (66.30 N/m) due to the elastically soft amorphous structures. The frictional forces of lithiated and unlithiated silicon nanowire were obtained within the range of 0.5-4.0 Hz and 0.01-200 nN for velocity and load dependency, respectively. We explain the trend of adhesion and modulus in light of the materials properties of silicon and lithiated silicon. The results suggest a useful method for chemical identification of the lithiated region during the charging and discharging process.

• Korean journal of food and cookery science
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• v.19 no.3
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• pp.396-402
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• 2003

The aim of this study was to investigate the quality changes of retort pouched seasoned-conger eel products during a 60 day of storage at 4, 15 and -20$^{\circ}C$. The seasoned-conger eel products was sterilized at either 100 or 121$^{\circ}C$ for 90min., and then vacuum packed in plastic film bags. When comparing their duality before and after sterilization, the pH and VBN of all the products slightly decreased, while the TBA values slightly increased after sterilization. The color value, b, of the product decreased after sterilization, while the L value rarely changed. During storage the pH and VBN of all the products were little changed at the storage temperatures of 15 and -20$^{\circ}C$. The TBA values increased after 30 and 60 days at 15$^{\circ}C$, and at 4 and -20$^{\circ}C$, respectively. As for color difference during storage, the L and a values were little changed during storage, while the b value increased. In conclusion, the quality of the retort pouched seasoned-conger eel products remained good during the 60 day storage period when chilled and frozen after sterilization, and could be consumed as an instant food, keeping an appropriate content and soft texture.