Molybdenum disulfide ( MoS2) has been one of the most promising members of transition-metal dichalcogenides materials. Attributed to the excellent electrical performance and special physical properties, MoS2 has been broadly applied in semiconductor devices, such as field effect transistors (FETs). At present, the exploration of further improving the performance of MoS2- based FETs (such as increasing the carrier mobility and scaling) has encountered a bottleneck, and the application of high-κ gate dielectrics has become an effective approach to change this situation. Atomic layer deposition (ALD) enables high-quality integration of MoS2 and high-κ gate dielectrics at the atomic level. In this review, we summarize recent advances in the fabrication of two-dimensional MoS2 FETs using ALD high-κ materials as gate dielectrics. We first briefly discuss the research background of MoS2 FETs. Second, we expound the electrical and other essential properties of high-κ gate dielectrics, which are essential to the performance of MoS2 FETs. Finally, we focus on the advances in fabricating MoS2 FETs with ALD high-κ gate dielectrics on MoS2, as well as the optimized ALD processes. In addition, we also look forward to the development prospect of this field.

This study examines the surface characteristics, electrical conductivity, electromagnetic wave blocking characteristics, infrared (IR) transmittance, stealth function, thermal characteristics, and moisture characteristics of IR thermal imaging cameras. Nylon film (NFi), nylon fabric (NFa), and 5 types of nylon mesh were selected as the base materials for aluminum sputtering, and aluminum sputtering was performed to study IR thermal imaging, color difference, temperature change, and so on, and the relationship with infrared transmittance was assessed. The electrical conductivity was measured and the aluminum-sputtered nylon film demonstrated 25.6kΩ of surface resistance and high electrical conductivity. In addition, the electromagnetic wave shielding characteristics of the sputtering-treated nylon film samples were noticeably increased as a result of aluminum sputtering treatment as measured by the electromagnetic wave blocking characteristics. When NFi and NFa samples with single-sided sputtering were placed on the human body (sputtering layer faced the outside air) and imaged using IR thermographic cameras, the sputtering layer displayed a color similar to the surroundings, showing a stealth effect. Moreover, the tighter the sample density, the better the stealth function. According to the L, a, b measurements, when the sputtering layer of NFi and NFa samples faced the outside air, the value of a was generally high, thereby demonstrating a concealing effect, and the E value was also high at 124.2 and 93.9, revealing a significant difference between the treated and untreated samples. This research may be applicable to various fields, such as the military wear, conductive sensors, electromagnetic wave shielding film, and others.

Recently, 3D printing has been actively studied. A representative material in this 3D printing technology is plastic, and PLA, an eco-friendly material, is widely used. FDM is widely used as a way to output these PLA materials. However, this method lacks mechanical properties compared to injection-molded products as it is a method of stacking materials by melting. Therefore, in this study, using an FDM-type 3D printer, a tensile test was performed after printing a tensile specimen with PLA filament with the layer angle and layer density as control factors. After that, changes in tensile properties according to the layer angle and density were compared and evaluated. As a result, to improve the tensile strength, the layer density had to be considered, and to improve the elastic modulus, both the layer angle and the layer density had to be considered.

In this study, additive manufacturing of a functionally graded material (FGM) as an alternative to joining dissimilar metals is investigated using directed energy deposition (DED). FGM consists of five different layers, which are mixtures of austenitic stainless steel (type 316 L) and low-alloy steel (LAS, ferritic steel) at ratios of 100:0 (A layer), 75:25 (B layer), 50:50 (C layer), 25:75 (D layer), and 0:100 (E layer), respectively, in each deposition layer. The FGM samples are successfully fabricated without cracks or delamination using the DED method, and specimens are characterized using optical and scanning electron microscopy to monitor their microstructures. In layers C and D of the sample, the tensile strength is determined to be very high owing to the formation of ferrite and martensite structures. However, the elongation is high in layers A and B, which contain a large fraction of austenite.

Since the beginning of the second Sino-Japanese war in 1937, the entire Korean Peninsula has entered a full-fledged wartime system. Japan enacted laws that strongly regulate the distribution of various resources for war, and the same was implemented in Joseon. In particular, as iron, copper, lead, tin, and aluminum were mobilized as raw materials for military supplies such as weapons, private distribution decreased significantly, which had a great impact on the construction industry. As the use of metal such as steel as building materials requires permission from the provincial governor, it has become difficult to supply and demand except for some military facilities. In addition, the Japanese Ministry of Commerce and Industry encouraged research and development and manufacturing to promote the so-called “substitute goods industry” to make up for the shortage of supplies. Products with improved performance through chemical treatment by injecting only a small amount of the same raw material than before or using alternative raw materials have been developed. It was intended to overcome the limitations of lack of raw materials through the chemical industry. In terms of building materials, various substitutes were produced due to the incorporation of petrochemicals and the use of synthetic resins. This trend continued even after the end of the war and served as one of the backgrounds for R&D and production of new materials without returning to the “substitute goods.”

고려엉겅퀴(Cirsium setidens Nakai)는 여러해살이 초본식물로서 식용이 가능하며 곤드레라고 부르기도 한다. 최근 고려엉겅퀴에 여뀌못 털진딧물(Capitophorus elaeagni, Del Guercio)의 발생이 확인되어 재배농가의 피해가 예상되고 있다. 이에 대한 친환경적인 방제방법 구명을 위 해 시판 유기농업자재를 이용하여 고려엉겅퀴 식물체에 발생한 여뀌못털진딧물에 대한 방제효과를 검정한 결과 pyrethrins+paraffinic oils 이 98% 수준의 방제가를 보여주었으며 pyrethrins+matrine+pyroligneous 가 약 95%의 방제가를, azadirachtin+rotenone 성분이 75% 이상의 방제효과를 보여주었다. 이중 pyrethrins 성분이 가장 좋은 효과를 주는 것으로 여겨지며 유기농업자재 살포로 인한 약해는 발생하지 않았다.