Salacca peel-based porous carbon (SPPC) with high surface area (1945 m2 g−1) and large specific pore volume (1.68 cm3 g−1) was prepared by pre-carbonization and K2CO3 activation method. Based on the TGA results, it can be estimated that up to 70 wt% of sulfur-active materials could be infiltrated into the pores of SPPC to form SPPC/S composite cathode for LiS battery. The porous structure of SPPC could act as a buffer layer against volume expansion and minimize the shuttle effect due to the penetration of intermediate polysulfides during cycle tests. Optimization on sulfur loading (50, 60 and 70 wt%) in SPPCC/S composite was also investigated. It was found that the SPPC/S composites with 60 wt% of sulfur loading had the best electrochemical performances. With 60 wt% of sulfur loading, SPPC/S composite electrodes showed excellent electrochemical performances in terms of high initial specific discharge capacity of 1006 mAh g− 1 at 0.5 C and capacity retention of 71% until the 100th cycle. For both cases of low and high sulfur loading, they caused much worse electrochemical performances. Based on the experimental results, it can be concluded that porous carbons derived from the salacca peel were promising materials for sulfur loading in LiS battery.

Nitrogen-doped carbons have attracted much attention due to their novel application in relation to gas storage. In this study, nitrogen-doped porous carbons were synthesized using SBA-15 as a template, polypyrrole as the carbon and nitrogen precursor, and KOH as an activating agent. The effect of the activation temperature (600–850°C) on the CO2 adsorption capacity of the obtained porous carbons was studied. Characterization of the resulting carbons showed that they were micro-/meso-porous carbon materials with a well-developed pore structure that varied with the activation temperature. The highest surface area of 1488 m2 g–1 was achieved at an activation temperature of 800°C (AC-800). The nitrogen content of the activated carbon decreased from 4.74 to 1.39 wt% with an increase in the activation temperature from 600 to 850°C. This shows that nitrogen is oxidized and more easily removed than carbon during the activation process, which indicates that C-N bonds are more easily ruptured at higher temperatures. Furthermore, CO2 adsorption isotherms showed that AC-800 exhibited the best CO2 adsorption capacity of 110 mg g–1 at 298 K and 1 bar.

This study was performed in order to obtain the effect of the compressive strength of the cured product with manufacturing conditions (amounts of fine aggregate and different types of alkali activator). Material which is the basis of the cured product was used for the blast furnace slag, which has a latent hydraulic activity. Consequently, when using sodium hydroxide as the alkali activator, it is possible to obtain a higher compressive strength than using the calcium hydroxide. And also, it can be added a 10% of fine aggregate with blast furnace slag to improve the compressive strength.

본 연구에서는 총백 특유의 향과 항산화 기능 등으로 알 려진 alliin과 allicin의 추출 최적 조건을 정립하기 위해 추 출용매, 추출온도, 추출시간 등을 달리하여 alliin과 allicin 의 함량을 측정하였다. 또한, 총백의 alliinase 활성화 조건 에 따른 allicin의 함량의 변화를 알아보기 위해 생총백을 물과의 혼합비율, 수침온도, 진탕시간을 달리하여 처리하여 allicin 함량을 비교하였다. 결과적으로, alliin은 총백 추출 조건 중 추출용매로 물을 사용하여 40oC에서 2시간 추출 하였을 때, 86.477 mg/g으로 최대함량을 보였으며, allicin의 경우, 70% ethanol, 70oC, 2시간 추출조건에서 1.371 mg/g 으로 최대함량을 나타냈다. 본 실험에서는 총백의 추출 조 건을 alliin의 함량이 크게 감소하지 않고, allicin의 함량이 최대로 추출될 수 있도록 70% ethanol, 70oC, 2시간으로 추출조건을 설정하였다. Alliinase 활성화 처리 조건에서는 생총백과 물을 1:1 혼합하여 40oC에서 30분간 진탕하였을 때, 0.111 mg/g로써 최대의 allicin 함량을 보였다. 본 실험 결과, 다양한 추출조건에서 alliin과 allicin의 함량이 높은 총백추출물을 제조함으로써 원가경쟁력이 높은 총백추출물 기반 기능성 소재 또는 식품을 개발하는데 기여할 수 있을 것으로 사료된다. 또한, alliinase 활성화를 통한 allicin의 최적 추출방법을 확립함으로써, 총백 이외의 마늘, 양파, 대파 등 allium 속 식물을 이용한 allicin 개발을 타겟으로 하는 연구자들뿐만 아니라 전반적인 기능성 식품 산업에 있어서 소재 개발을 위한 기초자료가 될 수 있을 것이다.

Condition of Construction Safety Training and its Vitalization in Chungbuk Area. The industrial accident rate of Korea has been declining each year but this does not necessarily mean that the safety consciousness of people has been strengthened. 94.3% of the overall industrial accidents occur in small/medium sized business (299 employees or less) and 97.5% of the accidents are in construction business. In Chungbuk area, small/medium sized business take up 99% of overall business and among them, 30% are construction business. Therefore, in order to resolve the safety issues, survey and research have been conducted with construction workers and manager and identified the causes and possible solution for improvement as following. First, most of the site workers and managers view safety training and equipment unnecessary as the work site is small in size. Second, the current safety trainings are being done with case study and visual teaching materials but the quality of the material, environment and instructors are very low and outdated. The quality of study materials and instructor need to be improved with professionalism. Third, 57% of surveyees think that the contents of training materials do not reflect the real situations and hazards at the work site and are not even in line with legal requirements. The safety trainings are being given perfunctorily. With on above researched issues, new method for vitalization of safety trainings and reducing and preventing the industrial accidents constructional site in Chungbuk area are to be suggested.

Short pitch fibers were prepared from petroleum based isotropic precursor pitch by melt-blown technology. The pitch fibers were stabilized in oxidizing condition, followed by steam activations at various conditions. The fiber surface and pore structures of the activated carbon fibers (ACFs) were respectively characterized by using SEM and applying BET theory from nitrogen adsorption at 77 K. The weight loss of the oxidized fiber was proportional to activation temperature and activation time, independently. The adsorption isotherms of the nitrogen on the ACFs were constructed and analyzed to be as Type I consisting of micropores mainly. The specific surface area of the ACFs proportionally increased with the weight loss at a given activation temperature. The specific surface area was ranged 850~1900 m2/g with pores of narrow distribution in sizes. The average pore size was ranged 5.8~14.1 a with the larger value from the more severe activation condition.