Probiotic functional foods are known to have various functional effects such as intestinal regulation, modulation of immune system, reduction of allergies, and lowering of cholesterol. The purpose of this study was to select probiotic strain that is most suitable for freeze-dried coffee for the development of functional coffee products. The survival rate of probiotics, at drinking condition of coffee, at acid, at bile and after freeze-dried in coffee were measured on 1 strain isolated from commercial freeze-dried coffee, 8 strains used as fermented milk starter, 1 Bifidobacterium and 1 Bacillus coagulans. Bacillus coagulans showed the highest survival rate from 2.4×107 cfu/g to 2.0×107 cfu/g especially after freeze-drying. The results at drinking condition of coffee, at acid tolerance, at bile tolerance and at storage test showed significantly better survival rate of Bacillus coagulans than that of control (Lactobacillus casei). Especially, Bacillus coagulans showed 3.8-fold higher survival rate at acid tolerance (pH 1, 120 minutes) than control. Thus, the lactic acid-producing Bacillus coagulans is characterized as a probiotic strain suitable for functional coffee formulation and commercialization.

The objectives of this study, which filled gaps in previous studies, were: (1) to find the optimal mixing condition of nanoemulsions containing oleoresin capsicum (OC), Tween 80, propylene glycol (PG), and sucrose monostearate (SES) by microfluidization; (2) to investigate their properties and stability depending on such factors as pH, temperature, and heating time; (3) to measure the effect of adding ascorbic acid. In order to test these objectives, the following three experiments were conducted: Firstly, in order to find the optimal mixing ratio, nanoemulsions containing OC - the mean diameter of which is smaller than 100 nm - were prepared through the process of microfluidization; and their mean particle size, zeta potential, and capsaicinoids were measured. The test results indicated that the mixing ratio at OC : Tween 80 : PG + water(1:2) = 1 : 0.2 : 5 was optimal. Secondly, the properties and stability of nanoemulsions were investigated with varying parameters. The test results illustrated that single-layer nanoemulsions and double-layer nanoemulsions coated with alginate were stable, irrespective of all the parameters other than/except for pH 3. Thirdly, the properties of nanoemulsions were then analyzed according to the addition of ascorbic acid. The results demonstrated that the properties of single-layer nanoemulsions were not affected by addition of ascorbic acid. In case of alginate double-layer nanoemulsions, the particle size was reduced, and zeta potential increased with the addition of ascorbic acid. In conclusion, the demonstrated stability of various nanoemulsions under the different conditions in the present study suggests that these findings may constitute a basis in manufacturing various food-grade products which use nanoemulsions-and indicate that food nanoemulsions, if adopted in the food industry, have the potential to satisfy both the functionality and acceptability requirements necessary to produce commercially marketable food-grade products.

Commercialized production of onion vinegar, which has biological activities formed through alcohol and acetic acid fermentation, requires standardization. The objective of this study was to determine optimal conditions of sugar contents (11~15 °Brix) and agitation rate (100~300 rpm) of fermenter in the alcohol-acetic fermentation for producing onion vinegar. The alcohol and total acidity contents increased, whereas contents of total sugars decreased during alcohol fermentation. Contents of alcohol of 13 and 15 °Brix reactants were about 8% in 36 hr and total acidities of all samples were below 0.2% in 60 hr. During acetic fermentation, total acidity increased with highest value at 9 days (3.2% in 100 rpm), 10 days (4.1% in 200 rpm) and 8 days (4.3% in 300 rpm), respectively. From these results, sugar contents (13 °Brix) were measured for alcohol fermentation and agitation rate (300 rpm) for fast fermentation method of vinegar. The contents of total phenols, flavonoids and quercetin in onion vinegar were 33.3 mg/100 g, 3.0 mg/100 g and 2.0 mg/100 g, respectively. Onion vinegar showed an antimicrobial activity against Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Salmonella typhimurium, Escherichia coli and Enterobacter aerogenes. Antioxidant effect of onion vinegar was 26.23% in DPPH radical inhibition and 58.58% in superoxide dismutase like activity, respectively. Fibrinolytic activity was 1.51 plasmin unit/mL in onion vinegar. In conclusion, onion vinegar processed by alcohol and acetic fermentation had nutritional values and potential biological activities.

실리콘 폼은 고성능 가스켓, 열 차폐, 진동 마운트 및 Enter 키 패드로 많은 산업 분야에서 난연성 소재로서 매우 유용하다. 실리콘 발포체는 실온에서 백금 촉매 및 무기필러 존재하에서 비닐기를 함유한 폴리실록산 (V-silicone) 및 수산기를 함유한 폴리실록산 (OH-silicone)과 하이드라이드를 함유 한 폴리실록산 (H-silicone)의 수소와의 수소축합반응의해 가교와 발포를 동시에 일으켜 제조하였다. 이 러한 방법은 종래의 발포와 경화를 각각 실시한 공정보다 매우 편리한 방법이다. 이 실험에 사용 된 기 능성 실리콘수지들은 1.0 meq/g의 vinyl기를 가진 점도 20 Pa-s의 V-silicone과 0.4 meq/g의 수산기를 가진 점도 50 Pa-s의 OH-silicone 및 7.5 meq/g의 하이드라이드기를 함유한 점도 0.06 Pa.s.의 H-silicone으로 구성되어 있다. 본 연구에서는 실리콘의 종류 및 함량, 촉매, 충전제 등의 변화에 따른 실리콘수지 발포체의 구조 및 기계적 특성에 미치는 영향을 연구하였다.백금 촉매는 실리콘 수지에 대하여 0.5 wt%이면 충분하였다. 낮은 점도의 OH-silicone의 첨가는 초 기 발포 속도를 높이며 발포체 밀도는 감소시키지만, 낮은 점도의 V-silicone의 첨가는, 인장 강도뿐만 아니라 신율도 감소시킨다. SF-3 조건에서 얻은 실리콘수지 발포체의 밀도, 인장강도 및 신율을 각각 0.58 g/cm3, 3.51 kgf/cm2 및 176 %를 얻을 수 있었다. 본 발포 시스템에서의 알루미나 충전재 역시 실리콘수지 발포체의 기계적 특성을 향상시키는 중요한 역할을 하였다.

Graphite was diffusion-bonded by hot-pressing to W-25Re alloy using a Ti interlayer. For the joining, a uniaxial pressure of 25 MPa was applied at 1600 oC for 2 hrs in an argon atmosphere with a heating rate of 10 oC min−1. The interfacial microstructure and elemental distribution of the W-25Re/Ti/Graphite joints were analyzed by scanning electron microscopy (SEM). Hot-pressed joints appeared to form a stable interlayer without any micro-cracking, pores, or defects. To investigate the high-temperature stability of the W-25Re/Ti/Graphite joint, an oxy-acetylene torch test was conducted for 30 seconds with oxygen and acetylene at a 1.3:1 ratio. Cross-sectional analysis of the joint was performed to compare the thickness of the oxide layer and its chemical composition. The thickness of W-25Re changed from 250 to 20 μm. In the elemental analysis, a high fraction of rhenium was detected at the surface oxidation layer of W-25Re, while the W-25Re matrix was found to maintain the initial weight ratio. Tungsten was first reacted with oxygen at a torch temperature over 2500 oC to form a tungsten oxide layer on the surface of W-25Re. Then, the remaining rhenium was subsequently reacted with oxygen to form rhenium oxide. The interfacial microstructure of the Ti-containing interlayer was stable after the torch test at a temperature over 2500 oC.

Al2O3 nanosol dispersed under ethanol or N-Methyl-2-pyrrolidone(NMP) was studied and optimized with various dispersion factors and by utilizing the silane modification method. The two kinds of Al2O3 powders used were prepared by thermal decomposition method from aluminum ammonium sulfate(AlNH4(SO4)2) while controlling the calcination temperature. Al2O3 sol was prepared under ethanol solvent by using a batch-type bead mill. The dispersion properties of the Al2O3 sol have a close relationship to the dispersion factors such as the pH, the amount of acid additive(nitric acid, acetic acid), the milling time, and the size and combination of zirconia beads. Especially, Al2O3 sol added 4 wt% acetic acid was found to maintain the dispersion stability while its solid concentration increased to 15 wt%, this stability maintenance was the result of the electrostatic and steric repulsion of acetic acid molecules adsorbed on the surface of the Al2O3 particles. In order to observe the dispersion property of Al2O3 sol under NMP solvent, Al2O3 sol dispersed under ethanol solvent was modified and solventexchanged with N-Phenyl-(3-aminopropyl)trimethoxy silane(APTMS) through a binary solvent system. Characterization of the Al2O3 powder and the nanosol was observed by XRD, SEM, ICP, FT-IR, TGA, Particles size analysis, etc.

This study was carried out to investigate the characterization of iron oxide nanotubes (INTs) by anodization method and applied adsorption isotherms and kinetic models for phosphate adsorption. SEM analysis was conducted to examine the INTs surface formation. Further XRD and XPS analysis were performed to observe the crystal structure of INTs before and after phosphate adsorption. AFM analysis was conducted to determine of Fe foil surface before and after anodization. Phosphate stock solution for adsorption experiment was prepared by KH2PO4. The batch experiment was conducted using 20 ml phosphate stock solution and 40 cm3 of INTs in 50 ml conical tube. Adsorption isotherms were applied Langmuir and Freundlich models for adsorption equilibrium test of INTs. Pseudo first order and pseudo second order models were applied for interpretation of adsorption rate by reaction time. The determination coefficient (R2) values of Langmuir and Freundlich models were 0.9157 and 0.8876 respectively.

Recently, the grain boundary diffusion process (GBDP), involving heavy rare-earth elements such as Dy and Tb, has been widely used to enhance the coercivity of Nd-Fe-B permanent magnets. For example, a Dy compound is coated onto the surface of Nd-Fe-B sintered magnets, and then the magnets are heat treated. Subsequently, Dy diffuses into the grain boundaries of Nd-Fe-B magnets, forming Dy-Fe-B or Nd-Dy-Fe-B. The dip-coating process is also used widely instead of the GBDP. However, it is quite hard to control the thickness uniformity using dip coating. In this study, first, a DyF3 paste is fabricated using DyF3 powder. Subsequently, the fabricated DyF3 paste is homogeneously coated onto the surface of a Nd-Fe-B sintered magnet. The magnet is then subjected to GBDP to enhance its coercivity. The weight ratio of binder and DyF3 powder is controlled, and we find that the coercivity enhances with decreasing binder content. In addition, the maximum coercivity is obtained with the paste containing 70 wt% of DyF3 powder.

N-doped carbon nanofibers as catalysts for oxygen-reduction reactions are synthesized using electrospinning and carbonization. Their morphologies, structures, chemical bonding states, and electrochemical performance are characterized. The optimized N-doped carbon nanofibers exhibit graphitization of carbon nanofibers and an increased nitrogen doping as well as a uniform network structure. In particular, the optimized N-doped carbon nanofibers show outstanding catalytic activity for oxygen-reduction reactions, such as a half-wave potential (E1/2) of 0.43 V, kinetic limiting current density of 6.2 mA cm-2, electron reduction pathways (n = 3.1), and excellent long-term stability after 2000 cycles, resulting in a lower E1/2 potential degradation of 13 mV. The improvement in the electrochemical performance results from the synergistic effect of the graphitization of carbon nanofibers and the increased amount of nitrogen doping.

제품유형과 가격, 브랜드 이미지 등의 상호작용이 소비자의 구매의도와 품질지각에 미치는 효과에 대해서는 다양한 현상을 관찰해 왔다. 그러나 제품유형과 제조방식의 상호작용이 이 요인들에 미치는 효과에 대해서는 연구가 드물었다. 그러나 3D프린터의 등장은 기계를 통한 자동화 생산과 수공예로 대표되던 제조방식에 3D프린팅이라는 새로운 방식을 추가하였고, 이러한 새로운 틀이 소비자의 구매의도와 품질지각에 영향을 미칠 가능성이 있기에 연구가 필요하다. 따라서 본 연구는 제품유형과 제조방식의 상호작용이 구매의도와 품질지각에 미치는 효과를 검증하기 위하여 이루어졌 다. 이를 위한 실험 1은 성격이 다른 제품유형(드론 vs. 바이올린 vs. 컵)을 선정하였고, 제품유형별로 선호하는 제조방식 이 다르게 나타나는지 측정하였다. 결과적으로 소비자들은 드론과 같은 최신제품은 3D프린팅 제작을, 바이올린은 수공예 제작을, 컵은 대량생산이 용이한 기계 제작을 선호하는 것으로 나타났다. 실험 2는 제품유형에 따른 제작방식 선호의 차이가 구매의도와 품질지각에 미치는 영향에 대한 검증을 시도하였다. 즉 드론은 3D프린팅 제조일 때 구매의도 가 가장 높았고, 바이올린은 수공예일 때 구매의도가 가장 높았으며, 컵은 기계 제작일 때 구매의도가 가장 높았다. 또한 드론은 제작방식 간 품질지각에 차이가 없었던 반면, 바이올린은 수공예의 품질을 가장 우수하다고 지각했고, 컵은 3D프린팅에서 품질을 가장 낮게 지각했다(컵은 3D프린팅 제작일 때 구매의도도 가장 낮았다). 본 연구가 소비자 심리학, 마케팅, 광고 등의 분야에 폭넓은 시사점을 줄 것으로 기대한다.

1,2-디브로모에탄을 이용한 2-에티닐피리딘의 무촉매중합을 통하여 이온성 전도성 고분자를 높은 수율로 합 성하였다. 합성한 고분자의 분자구조를 여러 가지 분석장비로 측정한 결과 설계한 N-(2-브로모에틸)피리디늄 브로마 이드를 갖는 공액구조 고분자임을 확인할 수 있었다. 이 고분자의 UV-Visible스펙트럼에서는 800 nm 까지 흡수 피 크를 보여주는데, 이는 공액구조 고분자의 π→ π* 전이에 기인한 것이다. 아울러 고분자의 전기전도도 및 전기광학 특성을 측정하고 분석하였다. 이 고분자는 도핑과 탈도핑 사이에서 매우 안정한 비가역 전기화학적 거동을 보였다.

The external R&D, which includes the adoption of the external technology and knowledge in addition to the internal R&D, is one of important factors for the innovation. Especially for small and medium-sized enterprises (SMEs), the external R&D has been considered as a key factor to carry out the innovation more efficiently due to the limitations of their resources and capacities. However, most of extant studies related to external R&D have focused on analyzing the influence of external R&D on innovation outputs or outcomes. Only a few studies have explored the impact of external R&D on the innovation efficiency. This study therefore investigates whether the external R&D effects the industry’s innovation efficiency and productivity. On this study, we used Korean manufacturing industry data of SMEs from 2012 to 2014 and employed a global Malmquist productivity analysis technique, which is based on the Data Envelopment Analysis (DEA), to assess the innovation efficiency and productivity. Innovation performances of external R&D group and internal R&D group are compared. Then, the sectoral patterns of both innovation efficiency and productivity are analyzed with respect to the technological intensity, which is introduced by OECD. The results show that the gap of innovation efficiency between external and internal R&D groups has gradually decreased because of the continuous improvement of the external R&D group’s performance, while the external R&D group lag behind the internal R&D group. In addition, patterns of the innovation efficiency and productivity change were different depending on the technological intensity, which means that the higher the technological intensity, the greater the effect of external R&D.

SCM activities in a company are considered as total innovation through synchronizing supply and demand while maintaining appropriate inventory level and reducing the business operating costs. Until now, even several researches are carried out on the SCM performance of the companies which have introduced and been operating SCM, the research on the cost analysis for the inventory which occurs frequently on supply chain is still insufficient. Especially, for the electronics industry in which the product depreciation is sharp caused by the short product life cycle and the complexity of distribution channels, even the inventory related costs are a major factor in business management, since the current estimated criteria of inventory costs are limited to the interest and maintenance management costs, the criteria do not reflect the total influence of the product depreciation and lost opportunity cost which are related to the business management. Furthermore, even though the rapid price drops of the distributor inventory caused by the frequent new model launch can be covered by the product manufacturers, the scale of total costs related to the inventory has not been conceived because the price compensation is traditionally considered as a market costs.In this research, we analyzed the inventory characteristics of electronics industry in which the price depreciation happens frequently, newly defining the estimated criteria of the product total inventory cost which includes price depreciation from the product manufacturers’ view. Finally we focus on the case study of a representative electronics company and verify the scale of the influence on management performance.

연구에서는, 전기방사법을 이용하여 산화철-산화그래핀(Fe3O4/GO, metallic graphene oxide; MGO)이 도입된 PVdF/MGO 복합나노섬유(PMG)를 제조하였으며, 이를 활용하여 비소제거에 대한 특성 평가를 진행하였다. MGO의 경우 In-situ-wet chemical 방법으로 제조하였으며, FT-IR, XRD분석을 진행하여, 형태와 구조를 확인하였다. 나노섬유 분리막의 기 계적 강도 개선을 위하여 열처리과정을 진행하였으며, 제조된 분리막의 우수한 기계적 강도 개선 효과를 확인할 수 있었다. 그러나, PMG 막의 경우, 도입된 MGO의 함량이 증가할수록 기계적 강도가 감소되는 경향성을 보여주었으며, 기공크기 분석 결과로부터, 0.3~0.45 μm의 기공크기를 가진 다공성 분리막이 제조되었음을 확인할 수 있었다. 수처리용 분리막으로의 활용 가능성 조사를 위해, 수투과도 분석을 실시하였다. 특히, PMG2.0 샘플의 경우 0.3 bar 조건에서, PVdF 나노섬유막(91 kg/m2h)에 비해 약 70% 향상된 결과값(153 kg/m2h)을 나타내었다. 또한, 비소 흡착실험 결과로부터, PMG 막의 경우, 비소3 가와 5가에 최대 81%, 68%의 높은 제거율을 보여주었으며, 흡착등온선 분석으로부터, 제조된 PMG 막의 경우 비소3가, 5가 모두 Freundlich 흡착거동을 따른다는 것을 확인하였다. 위 모든 결과로부터, PVdF/MGO 복합 나노섬유 분리막은 비소제거 및 수처리용 분리막으로 충분히 활용할 수 있을 것으로 판단된다.

Polyethersulfone (PES) 고분자 상변환막의 성능을 향상시키기 위해 PES 고분자에 나노 크기의 ZnO 무기입자를 함침시킨 혼합기질막(mixed matrix membrane)을 제조하고 특성을 평가하였다. PES-ZnO 혼합기질막은 ZnO 나노입자를 PES 대비 최대 0.375 wt%의 낮은 비율로 첨가시킨 PES-ZnO-NMP(N-methyl-1-pyrrolidone)로 이루어진 캐스팅 용액을 사용하여 상변환법을 통해 제조하였다. 제조된 혼합기질 막의 물성과 특성은 막의 단면구조 관찰, 접촉각 측정, 인장강도 측정, 순수 투과량 측정 및 BSA 단백질 용액의 한외여과 실험을 통해 평가하였다. 이 결과 혼합기질 막은 PES 고분자 matrix에 함유된 ZnO 나노입자로 인해 막의 친수성이 증가하여 막오염 발생이 억제되어 투과량이 증가하였다. ZnO 나노입자는 혼합기질막의 제조에 있어 막오염의 발생 억제와 투과량 증가에 유용하게 사용될 수 있는 무기물 첨가제임을 알 수 있다.

염수전기분해(saline water electrolysis) 또는 클로로-알칼리 막공정(chlor-alkali membrane process)은 양이온교환 막과 전극으로 구성되는 전해셀에 전기를 가하여, 고순도(> 99%)의 고부가가치 화합물(예 : 염소, 수소, 수산화나트륨)을 직 접 제조하는 화학공정이다. 염수전기분해의 경제성은 동일한 양의 화합물을 생산하기 위해 투여되는 에너지 소비량을 저감 시킴으로 달성될 수 있다. 이러한 이슈는 전해질이나 전극의 고유 저항을 줄이거나, 전해질과 전극 사이의 계면 저항을 감소 시킴으로 달성시킬 수 있다. 본 연구에서는 전자빔 동시조사법을 사용하여, 높은 화학적 안정성을 지닌 탄화수소계 술폰산 이 오노머 막의 표면에 높은 이온선택성을 갖는 고분자를 접목 시키는 시도가 이루어졌다. 이를 통해, 고분자 전해질 막의 이온 전도성을 보완함과 동시에, 전극과의 계면 저항을 감소시켜, 전기화학적 효율 향상이 이루어짐을 관찰하였다.

Spent mushroom substrate (SMS) has generally been used for the manufacture of animal feed and production of bio fuel. Limited research has been conducted in the utilization of SMS as a co-material for composting. Therefore, the main purpose of this study was to evaluate the feasibility of composting vegetable waste mixed with various ratios of SMS (30, 40, and 50%). The results showed that the C/N ratio decreased when both sawdust (from 22.0~28.8 to 17.7~20.4) and SMS (from 18.5~19.5 to 12.7~16.8) were applied for composing, owing to increased contents of nitrogen. A maturity test conducted using mechanical (Solvita) and germination tests revealed that both sawdust (92.0~101.9%) and SMS (87.8~89.2%) satisfied a criteria of maturity standard (70%). A correlation analysis between compost maturity and its chemical properties revealed that the C/N ratio and pH were the most dominant parameters for compost maturity. Overall, SMS could be utilized as a compost material and especially, vegetable waste mixed with SMS could provide sufficient nutrients for crop growth.

Graphene has shown exceptional properties for high performance devices due to its high carrier mobility. Of particular interest is the potential use of graphene nanoribbons as field-effect transistors. Herein, we introduce a facile approach to the fabrication of graphene nanoribbon (GNR) arrays with ~200 nm width using nanoimprint lithography (NIL), which is a simple and robust method for patterning with high fidelity over a large area. To realize a 2D material-based device, we integrated the graphene nanoribbon arrays in field effect transistors (GNR-FETs) using conventional lithography and metallization on highly-doped Si/SiO2 substrate. Consequently, we observed an enhancement of the performance of the GNRtransistors compared to that of the micro-ribbon graphene transistors. Besides this, using a transfer printing process on a flexible polymeric substrate, we demonstrated graphene-silicon junction structures that use CVD grown graphene as flexible electrodes for Si based transistors.