Porous Cu-14 wt% Co with aligned pores is produced by a freeze drying and sintering process. Unidirectional freezing of camphene slurry with CuO-Co3O4 powders is conducted, and pores in the frozen specimens are generated by sublimation of the camphene crystals. The dried bodies are hydrogen-reduced at 500oC and sintered at 800oC for 1 h. The reduction behavior of the CuO-Co3O4 powder mixture is analyzed using a temperature-programmed reduction method in an Ar-10% H2 atmosphere. The sintered bodies show large and aligned parallel pores in the camphene growth direction. In addition, small pores are distributed around the internal walls of the large pores. The size and fraction of the pores decrease as the amount of solid powder added to the slurry increases. The change in pore characteristics according to the amount of the mixed powder is interpreted to be due to the rearrangement and accumulation behavior of the solid particles in the freezing process of the slurry.

The composition of martensite transformation in NiAl alloy is determined using pure nickel and aluminum powder by vacuum hot press powder metallurgy, which is a composition of martensitic transformation, and the characteristics of martensitic transformation and microstructure of sintered NiAl alloys are investigated. The produced sintered alloys are presintered and hot pressed in vacuum; after homogenizing heat treatment at 1,273 K for 86.4 ks, they are water-cooled to produce NiAl sintered alloys having relative density of 99 % or more. As a result of observations of the microstructure of the sintered NiAl alloy specimens quenched in ice water after homogenization treatment at 1,273 K, it is found that specimens of all compositions consisted of two phases and voids. In addition, it is found that martensite transformation did not occur because surface fluctuation shapes did not appear inside the crystal grains with quenching at 1,273 K. As a result of examining the relationship between the density and composition after martensitic transformation of the sintered alloys, the density after transformation is found to have increased by about 1 % compared to before the transformation. As a result of examining the relationship between the hardness (Hv) at room temperature and the composition of the matrix phase and the martensite phase, the hardness of the martensite phase is found to be smaller than that of the matrix phase. As a result of examining the relationship between the temperature at which the shape recovery is completed by heating and the composition, the shape recovery temperature is found to decrease almost linearly as the Al concentration increases, and the gradient is about -160 K/ at% Al. After quenching the sintered NiAl alloys of the 37 at%Al into martensite, specimens fractured by three-point bending at room temperature are observed by SEM and, as a result, some grain boundary fractures are observed on the fracture surface, and mainly intergranular cleavage fractures.

This study aims to analyze the cooking and sensory characteristics of noodles to which different types and amounts of apples were added. Apple noodles were made by the addition of apple flour and apple concentrate to wheat flour in proportions of 0, 5, 10, 15, and 20%, respectively. Cooking time, weight after cooking, water loss after cooking, and rehydration rate were analyzed as cooking characteristics. Hardness, adhesiveness, cohesiveness, springiness, and chewiness were measured as texture characteristics, whereas sensory evaluation was performed on the appearance, color, taste, aroma, texture, and overall preference of noodles. The cooking time decreased as the amount of apple added increased, and the weight after cooking, water loss after cooking, and rehydration rate increased. The hardness and chewiness were decreased and the adhesiveness was increased as the amount of apple added was increased. The sensory test of apple noodles showed a higher score in taste and overall preference than that of the control. Furthermore, the addition of apples tended to produce a high score in all sensory tests, indicating that the addition of apples has a good effect on the quality of noodles. In particular, the addition of 10% apple concentrate showed high scores in all the tested characteristics.

The powder manufacturing process using the gas atomizer process is easy for mass production, has a fine powder particle size, and has excellent mechanical properties compared to the existing casting process, so it can be applied to various industries such as automobiles, electronic devices, aviation, and 3D printers. In this study, a modified A4032-xSn (x = 0, 1, 3, 5, and 10 wt.%) alloy with low melting point properties is investigated. After maintaining an argon (Ar) gas atmosphere, the main crucible is tilted; containing molten metal at 1,000℃ by melting the master alloy at a high frequency, and Ar gas is sprayed at 10 bar gas pressure after the molten metal inflow to the tundish crucible, which is maintained at 800℃. The manufactured powder is measured using a particle size analyzer, and FESEM is used to observe the shape and surface of the alloy powder. DSC is performed to investigate the change in shape, according to the melting point and temperature change. The microstructure of added tin (Sn) was observed by heat treatment at 575℃ for 10 min. As the content of Sn increased, the volume fraction increased to 1.1, 3.1, 6.4, and 10.9%.

본 연구에서는 유통 중인 분말 농산물가공품의 안전성 확보를 위하여 대형마트, 온라인 쇼핑몰에서 수거한 104건을 대상으로 다종농약다성분분석법으로 검사 가능한 잔류농약 373종 및 금속성 이물을 검사하였다. 품목별 수거 현황은 향신식물 33건(31.7%), 과일류 31건(29.8%), 채소류 25건(24.0%), 서류 5건(4.8%) 순이었다. 잔류농약은 전체 104건 중 7건에서 잔류허용기준 이내로 검출되어 6.7% 의 검출률을 보였으며 기준을 초과한 부적합 제품은 없었다. 깔라만시분말에서 chlorpyrifos, malathion, permethrin, 노니분말에서 fenoxanil, 쑥분말에서 tebuconazole, 파프리 카분말에서 tetraconazole, 신선초분말에서 etofenprox가 검출되었는데 이는 농산물중의 잔류농약이 가공품으로 이행 되었을 것으로 보인다. 금속성 이물은 22.1%(23건)의 검출률을 보였으며 기준을 초과한 제품은 계피분말, 강황분말, 새싹보리분말, 쑥 분말 등 16건이 발생하여 분말 농산물가공품에서는 금속 성이물의 관리가 무엇보다 중요할 것으로 판단된다. 금속성 이물(쇳가루)은 단단한 건조 농산물을 분말로 만드는 분쇄과정에서 금속성 재질의 롤밀, 칼날 등의 마찰로 인해 미세한 쇳가루가 발생하면서 분말 농산물가공품에 섞여 들어가는 것으로 추정된다. 분말 농산물가공품의 안전관리를 위해서는 원재료인 농산물의 안전성 확보를 기본으로 건조원료의 분쇄과정 중 발생하는 금속성 이물의 최소화, 금속성 이물 제거 장치의 설치, 분말 농산물가공품의 정기적인 모니터링 등의 체계적인 관리를 통해 제품의 안전성을 확보할 수 있을 것으로 기대된다.

Aluminum (Al) - based powders have attracted attention as key materials for 3D printing because of their excellent specific mechanical strength, formability, and durability. Although many studies on the fabrication of 3Dprinted Al-based alloys have been reported, the influence of the size of raw powder materials on the bulk samples processed by selective laser melting (SLM) has not been fully investigated. In this study, AlSi10Mg powders of 65 μm in average particle size, prepared by a gas atomizing process, are additively manufactured by using an SLM process. AlSi10Mg powders of 45 μm average size are also fabricated into bulk samples in order to compare their properties. The processing parameters of laser power and scan speed are optimized to achieve densified AlSi10Mg alloys. The Vickers hardness value of the bulk sample prepared from 45 μm-sized powders is somewhat higher than that of the 65 μm-sized powder. Such differences in hardness are analyzed because the reduction in melt pool size stems from the rapid melting and solidification of small powders, compared to those of coarse powders, during the SLM process. These results show that the size of the powder should be considered in order to achieve optimization of the SLM process.

본 연구의 목적은 레드비트 분말의 첨가가 냉장 저장중 비가열 돈육패티의 품질특성에 미치는 효과를 구명하기 위해 수행하였다. 실험구는 다음과 같이 구분하였다. 대조구: 아질산염 0.01%, T1: 아질산염 0.005%+레드비트 분말 0.1%, T2: 레드비트 분말 0.1%, T3: 레드비트 분말 0.3%, T4: 레드비트 분말 0.5%. 레드비트 분말을 첨가한 비가열 돈육패티의 품질특성에서 모든 처리구들이 수분, 보수력, pH에서 유사한 수준을 나타냈으나 (p>0.05), 가열 후 감량은 레드비트 분말의 첨가가 증가할수록 높아지는 결과를 나타내었다(p<0.05). 레드비트 분말의 첨가는 돈육패티의 조직특성과 관능평가에 큰 영향을 나타내지 않았으며, 레드비트 분말의 첨가가 증가할수록 적색도가 증가하는 결과를 나타내었다. 15일간의 냉장저장 중 레드비트 분말의 첨가는 비가열 돈육패티의 저장특성에 부정적인 영향을 나타내었으나 비가열 돈육패티의 외관을 크게 향상시킬 수 있는 우수한 착색제로서 사용할 수 있을 것으로 판단되었다.

A powder-in-sheath rolling method is applied to the fabrication of a carbon nano tube (CNT) reinforced copper composite. A copper tube with outer diameter of 30 mm and wall thickness of 2 mm is used as sheath material. A mixture of pure copper powder and CNTs with a volume content of 3 % is filled in a tube by tap filling and then processed to an 93.3 % reduction using multi-pass rolling after heating for 0.5 h at 400 oC. The specimen is then sintered for 1h at 500 oC. The relative density of the 3 vol%CNT/Cu composite fabricated using powder in sheath rolling is 98 %, while that of the Cu powder compact is 99 %. The microstructure is somewhat heterogeneous in width direction in the composite, but is relatively homogeneous in the Cu powder compact. The hardness distribution is also ununiform in the width direction for the composite. The average hardness of the composites is higher by 8Hv than that of Cu powder compact. The tensile strength of the composite is 280 MPa, which is 20 MPa higher than that of the Cu powder compact. It is concluded that the powder in sheath rolling method is an effective process for fabrication of sound CNT reinforced Cu matrix composites.

This study examined the quality characteristics of chicken breast emulsion-type sausages manufactured with different contents of Zanthoxylumschinifolium (Z.S.) powder (0, 1, 2 and 3%). The changes to the samples upon inclusion of Z.S. powder were monitored by measuring the proximate composition, pH, color, cooking yield, viscosity, texture profile analysis and protein solubility. The sausages manufactured with increasing amounts of Z.S. powder showed a decrease significantly in fat content (p<0.05), whereas the ash content increased. The pH of the cooked samples also decreased significantly with the increasing content of Z.S. powder (p<0.05). Before and after cooked lightness significantly decreased as the Z.S. powder content increased (p<0.05). The redness of the cooked samples also increased significantly with an increasing amount of Z.S. powder (p<0.05). Samples that contained 2% and 3% of Z.S. powder resulted in a significantly larger cooking yield compared to the control sample and the one containing 1% of Z.S. powder (p<0.05). The viscosity of the uncooked samples also increased with increasing amount of Z.S. powder. Furthermore, the samples containing 3% of Z.S. powder showed significantly lower levels of hardness and springiness than the control sample (p<0.05). In addition, the sample with 3% of Z.S. powder contained showed significantly higher total protein and myofibrillar protein levels than the other samples (p<0.05). Overall, the 3% of Z.S. powder chicken breast emulsion-type sausage performed well in most quality characteristic categories, and this formulation would be suitable for use in food manufacturing.

In this study, the quality characteristics and antioxidant activities of wet noodles added with doraji (Platycodon grandiflourm) powder at concentrations of 1%, 2%, 3%, and 4%, respectively, were investigated. The crude protein, crude fat, crude ash, crude fiber, and moisture contents of the dried doraji powder were 11.00%, 0.95%, 4.10%, 29.64%, and 6.21%, respectively. As the added amount of doraji powder increased, weight, volume, and water absorption of the wet noodles after cooking decreased. However, the turbidity of the soup increased. Color L values of wet and cooked noodles decreased, while a and b values increased by the addition of doraji powder. Texture measurement indicated that hardness, cohesiveness, springiness, and chewiness of the cooked noodles decreased by addition of doraji powder. The total polyphenol contents and DPPH radical scavenging activity in wet noodles added with doraji powder increased with increasing amounts of doraji powder. Finally, sensory evaluation of wet noodles added with doraji powder revealed that taste significantly decreased. However, flavor, color, texture, appearance, and overall acceptance scores for the 1% addition group ranked significantly higher than those of the other groups. In conclusion, these findings suggest that doraji powder could be used as functional food ingredients.

Cabbage is a biennial plant that is native to the shores of the Mediterranean. It contains dietary fiber, minerals, vitamin A, vitamin C, and anticarcinogenic phytochemicals. For the test, cabbage powder was added (5%, 10%, 20%, and 30%) to flour. The addition of cabbage powder significantly increased the specific gravity and viscosity of the batter and pH of both the batter and chiffon cake. The moisture in the chiffon cake increased due to the addition of cabbage powder. Also, the lightness of the cake significantly increased, whereas the redness and yellowness decreased as the amount of cabbage powder increased. The lightness and redness of crumbs from C0 were higher than other samples as each 59.48, －3.17, respectively. Except for the resilience, the hardness, gumminess, fracturability, and adhesiveness showed similar values in the C0, C5, and C10. In terms of consumer perception, the color, softness, flavor and overall consumer preference for the control chiffon cake were higher than C5, C10, C20, and C30. Nonetheless, for those that contain cabbage powder, C5 and C10 had relatively higher consumer preferences than C20 and C30. As a result, the optimum amount of cabbage powder for the chiffon cake would be from 5~10%.

Effective control of the heat generated from electronics and semiconductor devices requires a high thermal conductivity and a low thermal expansion coefficient appropriate for devices or modules. A method of reducing the thermal expansion coefficient of Cu has been suggested wherein a ceramic filler having a low thermal expansion coefficient is applied to Cu, which has high thermal conductivity. In this study, using pressureless sintering rather than costly pressure sintering, a polymer solution synthesis method was used to make nano-sized Cu powder for application to Cu matrix with an AlN filler. Due to the low sinterability, the sintered Cu prepared from commercial Cu powder included large pores inside the sintered bodies. A sintered Cu body with Zn, as a liquid phase sintering agent, was prepared by the polymer solution synthesis method for exclusion of pores, which affect thermal conductivity and thermal expansion. The pressureless sintered Cu bodies including Zn showed higher thermal conductivity (180 W/m·K) and lower thermal expansion coefficient (15.8×10−6/℃) than did the monolithic synthesized Cu sintered body.

Synthesis of composite powders for the Fe2O3-Zn system by mechanical alloying (MA) has been investigated at room temperature. Optimal milling and heat treatment conditions to obtain soft magnetic composite with fine microstructure were investigated by X-ray diffraction, differential scanning calorimetry (DSC) and vibrating sample magnetometer (VSM) measurement. It is found that α-Fe/ZnO composite powders in which ZnO is dispersed in α-Fe matrix can be obtained by MA of Fe2O3 with Zn for 4 hours. The change in magnetization and coercivity also reflects the details of the solid-state reduction process of hematite by pure metal of Zn during MA. Densification of the MA powders was performed in a spark plasma sintering (SPS) machine at 900 ~ 1,000 ℃ under 60 MPa. Shrinkage change after SPS of sample MA'ed for 5 hrs was significant above 300 ℃ and gradually increased with increasing temperature up to 800 ℃. X-ray diffraction results show that the average grain size of α-Fe in the α-Fe/ZnO composite sintered at 900 ℃ is in the range of 110 nm.

Powder characteristics, such as density, size, shape, thermal properties, and surface area, are of significant importance in the powder bed fusion (PBF) process. The powder required is exclusive for an efficient PBF process. In this study, the particle size distribution suitable for the powder bed fusion process was derived by modeling the PBF product using simulation software (GeoDict). The modeling was carried out by layering sintered powder with a large particle size distribution, with 50 μm being the largest particle size. The results of the simulation showed that the porosity decreased when the mean particle size of the powder was reduced or the standard deviation increased. The particle size distribution of prepared titanium powder by the atomization process was also studied. This study is expected to offer direction for studies related to powder production for additive manufacturing.

The Fe-22wt.%Cr-6wt.%Al foams were fabricated via the powder alloying process in this study. The structural characteristics, microstructure, and mechanical properties of Fe-Cr-Al foams with different average pore sizes were investigated. Result of the structural analysis shows that the average pore sizes were measured as 474 μm (450 foam) and 1220 μm (1200 foam). Regardless of the pore size, Fe-Cr-Al foams had a Weaire-Phelan bubble structure, and α-ferrite was the major constituent phase. Tensile and compressive tests were conducted with an initial strain rate of 10−3 /s. Tensile yield strengths were 3.4 MPa (450 foam) and 1.4 MPa (1200 foam). Note that the total elongation of 1200 foam was higher than that of 450 foam. Furthermore, their compressive yield strengths were 2.5 MPa (450 foam) and 1.1 MPa (1200 foam), respectively. Different compressive deformation behaviors according to the pore sizes of the Fe-Cr-Al foams were characterized: strain hardening for the 450 foam and constant flow stress after a slight stress drop for the 1200 foam. The effect of structural characteristics on the mechanical properties was also discussed.

Small fishing vessels are manufactured using FRP. Various studies have been conducted to increase the strength of the composite material by mixing alumina powder with resin. Tensile tests and flexural strength tests are conducted to examine the effect of alumina powder on the strength of GFRP. In the current study, resin/alumina composites at different alumina contents (i.e., 0, 1, 5, and 10 vol%) have been prepared. The physical and mechanical properties of the prepared composites have been investigated. From the results, the tensile strength of the specimen with alumina powder mixed in at 10% shows the highest value of 155.66 MPa. The tensile strength of the specimen mixed with alumina powder increases with the amount of alumina powder impregnated. In the flexural strength test, the flexural strength of neat resin without alumina powder has a highest value of 257.7 MPa. The flexural modulus of ALMix-5 has a highest value of 12.06 GPa. Barcol hardness of ALMix- 10 has a highest value of 51. We show that alumina powder leads to decreasing cracks on the surface and decreasing length area of delamination.

This study investigated the effect of apios powder on the quality characteristics of sausages. The results were as follows: pH values of the sausages were not significantly different among the samples. The amount of moisture content in the sausages decreased with increasing amount of apios powder. Increase in apios powder increased the lightness (L) value but decreased redness (a) and yellowness (b) values. Increase in apios powder increased the hardness and chewiness of sausage but decreased the adhesiveness. Apios powder had no significant effect on gumminess and springiness of the sausages among all samples. Total phenolic compound content and DPPH radical scavenging activity of apios powder added sausage significantly increased with increasing apios powder. Total bacterial counts of apios powder added sausage increased in all the samples as storage period passes and after 4 weeks of storage, the more adding ratio of apios powder was increased, the total bacterial count decreased. In view of above results, apios powder was considered to be food material suitable not only for functionality but also for developing sausage product of which preservation property is improved. From the results, 100% apios powder can be used to make optimum level for production of sausage.

Suaeda asparagoides (Miq.) is a salt marsh plant, long been prescribed in traditional medicine for the treatment of hypertension and liver toxification in Asian countries. The powder of S. asparagoides was added at the ratio of 0, 5, and 10%, respectively, of grain-type Meju to manufacture Doenjang in brine according to the salt concentration (8 and 12%). After 24 weeks of fermentation, the Doenjang samples were determined to have an anti-inflammatory effect on RAW 264.7 cells. Evaluation of the anti-inflammatory effect of Doenjang added S. asparagoides powder extracted using 80% EtOH, was performed to study the inhibition of pro-inflammatory factors such as NF-κB (nuclar factor κB), NO (nitric oxide), TNF-α (tumor necrosis factor alpha), IL-6 (interleukin-6), iNOS (inducible nitric oxide synthase), and COX-2 (cyclooxygenase-2) in lipopolysaccharide (LPS)-induced RAW 264.7 cells. The results showed that the Doenjang extracts reduced the production of NO, IL-6, COX-2, and iNOS increased in the LPS-stimulated RAW cell without cytotoxicity. In the case of the NF-κB and TNF-α there was no significant difference between the control and samples. In conclusion, these results suggest that Doenjang added with the S. asparagoides powder acts as functional fermented food with anti-inflammation effect.

Macro-porous carbon foams are fabricated using cured spherical phenolic resin particles as a matrix and furfuryl alcohol as a binder through a simple casting molding. Different sizes of the phenolic resin particles from 100– 450 μm are used to control the pore size and structure. Ethylene glycol is additionally added as a pore-forming agent and oxalic acid is used as an initiator for polymerization of furfuryl alcohol. The polymerization is performed in two steps; at 80oC and 200oC in an ambient atmosphere. The carbonization of the cured body is performed under Nitrogen gas flow (0.8 L/min) at 800oC for 1 h. Shrinkage rate and residual carbon content are measured by size and weight change after carbonization. The pore structures are observed by both electron and optical microscope and compared with the porosity results achieved by the Archimedes method. The porosity is similar regardless of the size of the phenolic resin particles. On the other hand, the pore size increases in proportion to the phenol resin size, which indicates that the pore structure can be controlled by changing the raw material particle size.

In this work, ultra-fine calcium oxide (CaO) powder derived from eggshells is used as the starting material to synthesize mineral trioxide aggregate (MTA). The prepared CaO powder is confirmed to have an average particle size of 500 nm. MTAs are synthesized with three types of fine CaO-based powders, namely, tricalcium silicate (C3S), dicalcium silicate (C2S), and tricalcium aluminate (C3A). The synthesis behavior of C3S, C2S and C3A with ultra-fine CaO powder and the effects of C3A content and curing time on the properties of MTA are investigated. The characteristics of the synthesized MTA powders are examined by X-ray diffraction (XRD), field emission-scanning electron microscope (FE-SEM), and a universal testing machine (UTM). The microstructure and compressive strength characteristics of the synthesized MTA powders are strongly dependent on the C3A wt.% and curing time. Furthermore, MTA with 5 wt.% C3A is found to increase the compressive strength and shorten the curing time.