Morphology control of a graphene nanosheet (GNS) is important for graphene-based battery electrodes to exhibit the increased practical surface area and the enhanced ion diffusion into the nanosheets. Nevertheless, it is very difficult to minutely control the shape of graphene nanosheets based on the conventional GNS suspension methods. In this work, we fabricated wrinkle textures of free-standing GNS for large area using Langmuir–Schaefer technique. The wrinkles are oriented vertically to the direction of the monolayer compression. The textured structure of GNS was obtained by cross-deposition of each layer with controlling the orientation of the wrinkle direction. These wrinkles can cause Li-ion to diffuse into the voids created by them and raise the specific surface area between the GNSs. Consequently, as a prospective anode for Li-ion battery, the wrinkled GNS multilayer, exhibits the high specific capacity of ~ 740 mAh g− 1 at 100 mA g−1 and the great power capability with ~ 404 mAh g− 1 being delivered even at 2 A g− 1. Furthermore, outstanding cycle performance of the wrinkled GNS multilayer is achieved over 200 cycles at 300 mA g−1 with high Coulombic efficiency of ~ 96%.

Lac 색소의 열수와 메탄올 추출물의 일부 유리아미노산과 그 유도체의 조성 및 함량, phenolic acid와 flavonoid의 조성 및 함량을 분석하고, 일부 피부미용 화장품 생리활성을 조사한 결과는 다음과 같다. 유리아미노산은 열수와 메탄올 추출물에서 각각 검출되지 않았으며, 단백질 비구성 아미노산 유도체는 열수 추출물에서 2종, 메탄올 추출물에서는 3종이 검출되었다. Phenolic acid와 flavonoids의 조성 및 함량분석에서, phenolic acid의 경우 열수 추출물에서 2종, 메탄올 추출물에서 5종이 검출되었다. 또한 flavonoids의 경우 열수 추출물에서는 검출되지 않았으나, 메탄올 추출물에서는 rutin과 taxifolin이 약간 존재하는 것으로 나타났다. DPPH radical 소거 활성은 메탄올 추출물이 40.43 ± 0.21%로 열수 추출물에서보다 약간 높게 나타났고, Tyrosinase 저해 활성은 메탄올 추출물이 열수 추출물에서 보다 약 2배 정도 높은 것으로 나타났다. HaCaT 세포주에 대한 세포독성은 모든 처리 농도에서 나타나지 않았으며, 처리 농도가 증가함에 따라 세포 생장이 증가하는 경향이었다.

To investigate the effect of gas dispersing carbon nanotubes (CNTs) and hot pressing method on the transparency and the conductivity of thin films, the free arc was used to disperse the CNTs in a high dispersion rate, and the dispersed CNTs were rapidly pressed into the surface of the PET film by hot pressing to obtain electrical conductivity. The relationship between the light transmission and sheet resistance of the film was studied by changing the deposition time and the presence or absence of electrostatic adsorption. It was found that the CNTs modified film still retains good electrical conductivity (sheet resistance up to 6 × 104 Ω, light transmittance 69%) through the cleaning of surfactants and ultrasonic waves, which proves that hot pressing is a simple physical method to achieve effective combination of CNTs and films.

A new free-living marine nematode species of the genus Belbolla Andrássy, 1973 belonging to the family Enchelidiidae is described based on specimens collected from the sediment of a subtidal benthic environmental habitat in the East Sea, Korea. Belbolla wonkimi sp. nov. differs from its congeners by the combination of the following characteristics: a relatively long body (3263-3396 μm), the absence of ocelli, nine oesophageal bulbs in the posterior pharynx, well-developed two winged precloacal supplements, longer spicule length (115-130 μm, 1.6-1.8 anal body diameter long), and a triangle-shaped shorter gubernacular apophysis (17-18 μm). Comparative tables on the biogeographical and morphological characteristics of Belbolla species are presented. A DIC (differential interference contrast) photomicrograph of the new species is also provided. This is the first taxonomic report on the genus Belbolla from Korean waters.

The governing equation for a dome-type shallow spatial truss subjected to a transverse load is expressed in the form of the Duffing equation, and it can be derived by considering geometrical non-linearity. When this model under constant load exceeds the critical level, unstable behavior is appeared. This phenomenon changes sensitively as the number of free-nodes increases or depends on the imperfection of the system. When the load is a periodic function, more complex behavior and low critical levels can be expected. Thus, the dynamic unstable behavior and the change in the critical point of the 3-free-nodes space truss system were analyzed in this work. The 4-th order Runge-Kutta method was used in the system analysis, while the change in the frequency domain was analyzed through FFT. The sinusoidal wave and the beating wave were utilized as the periodic load function. This unstable situation was observed by the case when all nodes had same load vector as well as by the case that the load vector had slight difference. The results showed the critical buckling level of the periodic load was lower than that of the constant load. The value is greatly influenced by the period of the load, while a lower critical point was observed when it was closer to the natural frequency in the case of a linear system. The beating wave, which is attributed to the interference of the two frequencies, exhibits slightly more behavior than the sinusoidal wave. And the changing of critical level could be observed even with slight changes in the load vector.

Digital channels are becoming increasingly important in consumer purchase decisions. Yet, the availability of several different channels present consumers the opportunity to switch between one and another, such a phenomenon is called cross-channel free riding. This research aims therefore at exploring whether cognitive dissonance and opportunistic behavior are relevant antecedents of cross-channel free riding.

Free-standing hybridized electrode consisting of double-walled carbon nanotubes (DWNTs) and activated carbon have been fabricated for flexible supercapacitor applications. The xanthan-gum, used in our methodology, showed high ability in dispersing the strongly bundled DWNTs, and was then effectively converted to activated carbon with large surface area via chemical activation. The homogeneously dispersed DWNTs within xanthan-gum derived activated carbon acted as both electrical path and mechanical support of electrode material. The hybridized film from highly dispersed DWNTs and activated carbon was mechanically strong, has high electrical conductivity, and exhibited high specific capacitance of 141.5 F/g at the current density of 100 mV/s. Our hybridized film is highly promising as electrode material for flexible supercapacitors in wearable device.

토마토와 박과류채소의 유기농산물을 생산하기 위하여 무농약으로 재배하는 시설하우스에서 최근 문제되는 병해를 조사한 결과 토마토 잎곰팡이병과 토마토반점위조바이러스병, 토마토퇴록바이러스병, 박과류 쥬키니황화모자이크바이러스병, 박과류 흰가루병 등의 피해가 심한 것으로 조사되었다. 농약을 사용하여 일반재배를 하는 시설하우스에 비해 무농약재배 하우스에서 재배되는 작물에서 병 발생 시기가 더 빠르고 병 발생도 심한 것으로 나타났으며, 총채벌레와 진딧물 등에 의해 매개되는 바이러스병 피해가 심한 것으로 조사되었다. 따라서 우수한 유기농산물을 생산하기 위해서는 병해충방제를 효율적으로 하는 것이 중요하며, 병 발생 피해를 최소화기 위해서는 포장위생과 물리적 차단, 유기농업자재나 미생물제 등을 종합적으로 활용하여 예방적으로 방제하는 것이 가장 중요하다.

China Pilot Free Trade Zone is a "policy practice zone," and China has already established 18 pilot FTZs since the approval of Shanghai Pilot FTZ in Sept. 2013. Pilot FTZs have become high grounds for Chinese economic reform through 'optimization of business environment', 'facilitation of investment & trade', and 'policy innovation in various fields such as financial services and real economy.' Construction of pilot FTZ has aggressively extended national strategies such as active service, construction of "One Belt, One Road" Initiative, cooperative development of Jingjinji Metropolitan region (Beijin-Tianjin-Hebei), integrated development of Yangtze River Delta Economic Zone, and revitalization of northeast China, etc. as well as collaboration with surrounding nations. Recent entry of new stage of China-Korea relations has great potential of complementary cooperation. As a "policy practice zone" of Chinese economic reform, Pilot FTZs have arranged business environment facilitated with legislation and internationalization, regulation system suitable for international trade-investment rules, and open financial environment through system innovation & reform in various fields such as investment, trade, and finance, etc. This is giving a new motivation for higher level and broadened area of China-Korea economic relations.

본 논문은 자발적 지리정보인 오픈스트리트맵(OpenStreetMap, OSM)을 활용하여 중학교 자유학기제의 지도 수업과 학생 활동을 분석한 연구이다. 본 연구를 통해 지도 수정과 편집이 자유로운 오픈스트리트맵을 활용하여 학생들이 직접 지도 편집을 수행하고 중학교 자유학기제 수업에 적용할 수 있는 학생 활동 및 수행 평가 내용을 제안하였다. 이를 위해 총 8차시의 주제선택 활동을 계획하였고, 지형지물의 위치, 굴곡, 형태, 크기, 면적에 대해 학생들은 점, 선, 면의 지도 기호를 사용하여 지도 입력과 수정. 편집 활동을 진행하였다. 학생 활동 평가를 위해 학생들의 지도 정보 입력 및 편집 활동 결과 내용을 분석하고 이를 다섯 단계의 지도 습득 수준으로 분류하여 각 활동 수준의 특성을 살펴보았다. 이러한 논의를 바탕으로 본 연구는 인터넷 지도와 모바일 기기의 지도 활용 환경을 감안하여 학생 주도의 디지털 지도 학습과 지도 교육 관련 연구의 필요성을 제기하고자 한다.